init files

.gitignore

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+runtime/
+dist/
+build/
+__pycache__/
+*.log

.idea/.gitignore

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+# Default ignored files
+/shelf/
+/workspace.xml
+# Datasource local storage ignored files
+/dataSources/
+/dataSources.local.xml
+# Editor-based HTTP Client requests
+/httpRequests/

.idea/deployment.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="PublishConfigData" remoteFilesAllowedToDisappearOnAutoupload="false">
+    <serverData>
+      <paths name="hyu3@linuxsrv01.ece.uw.edu:22">
+        <serverdata>
+          <mappings>
+            <mapping local="$PROJECT_DIR$" web="/" />
+          </mappings>
+        </serverdata>
+      </paths>
+    </serverData>
+  </component>
+</project>

.idea/inspectionProfiles/Project_Default.xml

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+<component name="InspectionProjectProfileManager">
+  <profile version="1.0">
+    <option name="myName" value="Project Default" />
+    <inspection_tool class="PyPep8NamingInspection" enabled="true" level="WEAK WARNING" enabled_by_default="true">
+      <option name="ignoredErrors">
+        <list>
+          <option value="N806" />
+        </list>
+      </option>
+    </inspection_tool>
+  </profile>
+</component>

.idea/misc.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_16" project-jdk-name="Python 3.9 (sshcec)" project-jdk-type="Python SDK">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
+</project>

.idea/modules.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/sshcec.iml" filepath="$PROJECT_DIR$/sshcec.iml" />
+    </modules>
+  </component>
+</project>

build.spec

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+# -*- mode: python ; coding: utf-8 -*-
+
+
+block_cipher = None
+
+
+a = Analysis(['toplevel.py', 'get_runtime.py'],
+             pathex=['D:\\eyhc\\sshcec'],
+             binaries=[],
+             datas=[],
+             hiddenimports=[],
+             hookspath=[],
+             runtime_hooks=[],
+             excludes=[],
+             win_no_prefer_redirects=False,
+             win_private_assemblies=False,
+             cipher=block_cipher,
+             noarchive=False)
+pyz = PYZ(a.pure, a.zipped_data,
+             cipher=block_cipher)
+exe = EXE(pyz,
+          a.scripts,
+          a.binaries,
+          a.zipfiles,
+          a.datas,
+          [],
+          name='CTOS-wrapper',
+          debug=False,
+          bootloader_ignore_signals=False,
+          strip=False,
+          upx=True,
+          upx_exclude=[],
+          runtime_tmpdir=None,
+          console=False )

files.py

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+import paramiko
+
+
+
+transport = paramiko.Transport(("linux-lab-055.ece.uw.edu", 22))
+transport.connect(None, "hyu3", ":Eric200002182919")
+
+# Go!
+sftp = paramiko.SFTPClient.from_transport(transport)
+sftp.chdir("Documents")
+print(sftp.listdir())
+# sftp.put('VNC_UWEE.jar', 'VNC_UWEE.jar')
+# sftp.get('concentration.csv','concentration.csv')

gen-servers.py

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+for i in range(41, 81):
+    print(f'"linux-lab-0{i}.ece.uw.edu"', end=" ")

get_runtime.py

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+import os, platform, zipfile, tarfile, urllib.request
+
+JAVA_VER = '8'
+RUNTIME_PATH = os.path.join(os.getcwd(), 'runtime')
+
+
+def get_platform_ext() -> tuple:
+    if platform.system() == "Windows":
+        if platform.architecture()[0] == "64bit":
+            return "x64-windows", "zip"
+        else:
+            return "x86-windows", "zip"
+    elif platform.system() == "Linux" and platform.architecture()[0] == "64bit":
+        return "x64-linux", "tar.gz"
+    elif platform.system() == "Darwin" and platform.architecture()[0] == "64bit":
+        return "macos", "tar.gz"
+    else:
+        raise ValueError("Unsupported system. Currently only supports windows and 64-bit linux/MacOS systems!")
+
+
+# def get_download_url(version: str, arch_os: str, file_ext: str, jv_type: str = "jdk") -> str:
+#     if not jv_type == "jdk" or not jv_type == "jre":
+#         raise ValueError(f'{jv_type} is not an acceptable type. Accepted types are either "jdk" or "jre"')
+#     if version == '1.8':
+#         version = '8'
+#     return f"https://corretto.aws/downloads/latest/amazon-corretto-{version}-{arch_os}-{jv_type}.{file_ext}"
+
+
+def install_runtime(jv_ver: str = JAVA_VER) -> str:
+    """
+    :acknowledge: https://stackoverflow.com/a/7244263
+    """
+    os_arch, ext = get_platform_ext()
+    url = f"https://corretto.aws/downloads/latest/amazon-corretto-{jv_ver}-{os_arch}-jdk.{ext}"
+    print(url)
+    try:
+        urllib.request.urlretrieve(url, f'Runtime.cash')
+        if ext == "zip":
+            with zipfile.ZipFile(f'Runtime.cash') as z:
+                jv_name = z.namelist()[0].replace('/', '')
+                z.extractall(path=RUNTIME_PATH)
+        else:  # non-windows, which assume is the tar.gz file
+            with tarfile.open(f'Runtime.cash', 'r:gz') as t:
+                jv_name = t.getnames()[0].replace('/', '')
+                t.extractall(path=RUNTIME_PATH)
+        return jv_name
+    finally:
+        os.unlink(f'Runtime.cash')
+
+
+def get_java_path(jv_ver: str = JAVA_VER, directory: str = RUNTIME_PATH) -> str:
+    if not os.path.exists(directory):
+        return os.path.join(directory, install_runtime(jv_ver), "bin", "java.exe")
+    if jv_ver == '8':
+        jv_ver = '1.8'
+    jv_path = [root for root, d, f in os.walk(RUNTIME_PATH, topdown=False) if jv_ver in root and '\\bin' in root]
+    if jv_path:
+        return os.path.join(jv_path[0], "java.exe")
+    else:
+        return os.path.join(directory, install_runtime(jv_ver), "bin", "java.exe")
+
+
+if __name__ == '__main__':
+    print(get_java_path())

get_server.py

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+import paramiko
+import re
+
+
+class ShellHandler:
+
+    def __init__(self, host, user, psw):
+        self.ssh = paramiko.SSHClient()
+        self.ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+        self.ssh.connect(host, username=user, password=psw, port=22)
+
+        channel = self.ssh.invoke_shell()
+        self.stdin = channel.makefile('wb')
+        self.stdout = channel.makefile('r')
+
+    def __del__(self):
+        self.ssh.close()
+
+    def execute(self, cmd):
+        """
+
+        :param cmd: the command to be executed on the remote computer
+        :examples:  execute('ls')
+                    execute('finger')
+                    execute('cd folder_name')
+        """
+        cmd = cmd.strip('\n')
+        self.stdin.write(cmd + '\n')
+        finish = 'end of stdOUT buffer. finished with exit status'
+        echo_cmd = 'echo {} $?'.format(finish)
+        self.stdin.write(echo_cmd + '\n')
+        shin = self.stdin
+        self.stdin.flush()
+
+        shout = []
+        sherr = []
+        exit_status = 0
+        for line in self.stdout:
+            if str(line).startswith(cmd) or str(line).startswith(echo_cmd):
+                # up for now filled with shell junk from stdin
+                shout = []
+            elif str(line).startswith(finish):
+                # our finish command ends with the exit status
+                exit_status = int(str(line).rsplit(maxsplit=1)[1])
+                if exit_status:
+                    # stderr is combined with stdout.
+                    # thus, swap sherr with shout in a case of failure.
+                    sherr = shout
+                    shout = []
+                break
+            else:
+                # get rid of 'coloring and formatting' special characters
+                shout.append(re.compile(r'(\x9B|\x1B\[)[0-?]*[ -/]*[@-~]').sub('', line).
+                             replace('\b', '').replace('\r', ''))
+
+
+s = ShellHandler('linux-lab-055.ece.uw.edu', 'hyu3', ':Eric200002182919')
+s.execute("vncserver -list")
+
+
+# ssh = paramiko.SSHClient()
+# ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+# # linux-lab-055.ece.uw.edu
+# ssh.connect("linux-lab-055.ece.uw.edu", username="hyu3", password=":Eric200002182919")
+# ssh_stdin, ssh_stdout, ssh_stderr = ssh.exec_command("vncserver -list")
+#
+# xdisplay = ssh_stdout.readlines()[-1]
+#
+# if "DISPLAY" in xdisplay:
+#     ssh_stdin, ssh_stdout, ssh_stderr = ssh.exec_command('vncserver -interface 0.0.0.0 && vncserver -list')
+#     xdisplay = ssh_stdout.readlines()[-1]
+#
+# print(xdisplay.split()[0][1:])

interactive.py

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+# modified from https://github.com/paramiko/paramiko/blob/main/demos/interactive.py
+
+import socket
+import sys
+from paramiko.py3compat import u
+
+# windows does not have termios...
+try:
+    import termios
+    import tty
+
+    has_termios = True
+except ImportError:
+    has_termios = False
+
+
+def interactive_shell(chan):
+    if has_termios:
+        posix_shell(chan)
+    else:
+        windows_shell(chan)
+
+
+def posix_shell(chan):
+    import select
+
+    oldtty = termios.tcgetattr(sys.stdin)
+    try:
+        tty.setraw(sys.stdin.fileno())
+        tty.setcbreak(sys.stdin.fileno())
+        chan.settimeout(0.0)
+
+        while True:
+            r, w, e = select.select([chan, sys.stdin], [], [])
+            if chan in r:
+                try:
+                    x = u(chan.recv(1024))
+                    if len(x) == 0:
+                        sys.stdout.write("\r\n*** EOF\r\n")
+                        break
+                    sys.stdout.write(x)
+                    sys.stdout.flush()
+                except socket.timeout:
+                    pass
+            if sys.stdin in r:
+                x = sys.stdin.read(1)
+                if len(x) == 0:
+                    break
+                chan.send(x)
+
+    finally:
+        termios.tcsetattr(sys.stdin, termios.TCSADRAIN, oldtty)
+
+
+# thanks to Mike Looijmans for this code
+def windows_shell(chan):
+    import threading
+
+    sys.stdout.write(
+        "Line-buffered terminal emulation. Press F6 or ^Z to send EOF.\r\n\r\n"
+    )
+    global cmdout
+    def writeall(sock):
+        global cmdout
+        line = 0
+        while True:
+            data = sock.recv(256)
+            if not data:
+                sys.exit(0)
+            cmdout = data.decode("utf-8")
+            if "]$" in data.decode("utf-8"):
+                line += 1
+            if line > 1:
+                sys.stdout.write("press ENTER to continue\n")
+            sys.stdout.write(cmdout)
+            sys.stdout.flush()
+
+
+    writer = threading.Thread(target=writeall, args=(chan,))
+    writer.start()
+
+    try:
+        chan.send("/homes/hyu3/anaconda3/envs/Documents/bin/python /homes/hyu3/Documents/dummy.py\n")
+        # chan.send("vncpasswd\n")
+        while True:
+            if "]$" in cmdout:
+                chan.send("exit\n")
+                break
+            d = sys.stdin.read(1)
+            if not d:
+                break
+            chan.send(d)
+    except (EOFError, OSError):
+        # user hit ^Z or F6
+        pass
+

se.py

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+import cryptography.fernet
+import argon2
+import base64
+import random
+
+# def encrypt_data(data_bytes, password, salt):
+#     password_hash = argon2.argon2_hash(password=password, salt=salt)
+#     encoded_hash = base64.urlsafe_b64encode(password_hash[:32])
+#     encryptor = cryptography.fernet.Fernet(encoded_hash)
+#     return encryptor.encrypt(data_bytes)
+#
+#
+# def decrypt_data(cipher_bytes, password, salt):
+#     password_hash = argon2.argon2_hash(password=password, salt=salt)
+#     encoded_hash = base64.urlsafe_b64encode(password_hash[:32])
+#     decryptor = cryptography.fernet.Fernet(encoded_hash)
+#     return decryptor.decrypt(cipher_bytes)
+
+import bcrypt
+from getpass import getpass
+master_secret_key = getpass('tell me the master secret key you are going to use')
+salt = bcrypt.gensalt()
+combo_password = "1234'".encode('utf-8') + salt + master_secret_key
+hashed_password = bcrypt.hashpw(combo_password, salt)
+
+
+bcrypt

sshcec.iml

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+<?xml version="1.0" encoding="UTF-8"?>
+<module type="PYTHON_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <excludeFolder url="file://$MODULE_DIR$/venv" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

tester.py

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+import paramiko, os, subprocess, interactive
+
+
+sshClient = paramiko.SSHClient()
+sshClient.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+sshClient.connect('linux-lab-055.ece.uw.edu', username='hyu3', password=':Eric200002182919')
+
+# ssh_stdin, ssh_stdout, ssh_stderr = sshClient.exec_command("/homes/hyu3/anaconda3/envs/Documents/bin/python /homes/hyu3/Documents/dummy.py")
+# print(ssh_stdout.readlines())
+#
+# ssh_stdin, ssh_stdout, ssh_stderr = sshClient.exec_command("a")
+# print(ssh_stdout.readlines())
+#
+# ssh_stdin, ssh_stdout, ssh_stderr = sshClient.exec_command("b")
+# print(ssh_stdout.readlines())
+
+channel = sshClient.get_transport().open_session()
+channel.get_pty()
+channel.invoke_shell()
+interactive.interactive_shell(channel)
+sshClient.close()
+

toplevel.py

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+import paramiko, os, sys, subprocess, get_runtime, wx  # , keyring
+from typing import NoReturn
+from ui import Frame
+from threading import Thread
+
+
+def main():
+    host = frame.host.GetValue()
+    localhost = frame.localhost.GetValue()
+    netid = frame.net_id.GetValue()
+    sshPass = frame.password.GetValue()
+    password = frame.vnc_passwd.GetValue()
+    kill_when_exit = frame.kill_when_exit.GetValue()
+
+    if not host or not localhost or not netid or not sshPass or not password:
+        wx.MessageBox("At least one of the box are left empty. Please make sure you fill out ALL boxes!!",
+                      "Empty Input", wx.ICON_ERROR)
+        return
+    frame.run.Enable(False)
+    ssh = paramiko.SSHClient()
+    sys.stdout.write(f'connecting to {host}\n')
+    frame.status.SetLabelText(f'connecting to host')
+    port = get_server(ssh, host, netid, sshPass, password)
+    if int(port) == -1:
+        wx.MessageBox("Your netID and password for that netID does not match the one in the ECE system!", "Wrong "
+                                                                                                          "Credentials", wx.ICON_ERROR)
+        frame.run.Enable(True)
+        frame.status.SetLabelText(u"Click 'RUN' to begin, hover over any boxes to show hints")
+        return
+    display = port
+    if int(port) < 10:
+        port = "0" + port
+    port = "59" + port
+    java = os.path.join(get_runtime.RUNTIME_PATH, get_runtime.get_java_path())
+    frame.status.SetLabelText(f'initializing java')
+    vnc_cmd = f'{java} -jar VNC_UWEE.jar -host="{localhost}" -port="{port}" -sshHost="{host}" -sshUser="{netid}" -sshPassword="{sshPass}" -password="{password}"'
+    frame.status.SetLabelText(f'VNC session started!')
+    out = subprocess.Popen(vnc_cmd, shell=True, stdout=subprocess.PIPE, stdin=subprocess.PIPE, stderr=subprocess.PIPE)
+    stdout, stderr = out.communicate()
+    open("launcher.log", "w").write(stderr.decode('utf-8'))
+    if out.returncode:
+        sys.stderr.write(f"{stderr.decode('utf-8')}\nProgram crashed with code {out.returncode}")
+
+    if kill_when_exit:
+        kill_srv(ssh, host, netid, sshPass, display)
+    frame.run.Enable(True)
+    frame.status.SetLabelText(u"Click 'RUN' to begin, hover over any boxes to show hints")
+
+
+def get_server(client: paramiko.SSHClient, host: str, username: str, password: str, vnc_passwd: str) -> str:
+    client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+    try:
+        client.connect(host, username=username, password=password)
+    except paramiko.ssh_exception.AuthenticationException:
+        return '-1'
+    sys.stdout.write("connected, sending command\n")
+    ssh_stdin, ssh_stdout, ssh_stderr = client.exec_command("vncserver && vncserver -list")
+    ssh_stdin.channel.shutdown_write()
+
+    if "You will require a password to access your desktops" in ssh_stderr.read().decode('utf-8'):
+        # create the vncserver's password if not done so, then create the session again and just return, since ssh_stdout did not refreshes outside the if
+        # TODO: add option that user can have a view-only password
+        ssh_stdin, ssh_stdout, ssh_stderr = client.exec_command("vncpasswd")
+        ssh_stdin.write(f"{vnc_passwd}\n")
+        ssh_stdin.write(f"{vnc_passwd}\n")
+        ssh_stdin.write("n\n")
+        ssh_stdin.flush()
+        ssh_stdin, ssh_stdout, ssh_stderr = client.exec_command("vncserver && vncserver -list")
+        return ssh_stdout.readlines()[-1].split()[0][1:]
+    return ssh_stdout.readlines()[-1].split()[0][1:]
+
+
+def kill_srv(client: paramiko.SSHClient, host: str, username: str, password: str, port: str) -> NoReturn:
+    client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+    client.connect(host, username=username, password=password)
+    client.exec_command(f"vncserver -kill :{port}")
+
+
+def on_chk(e):
+    if frame.localhost_ck.GetValue():
+        frame.localhost.Enable(False)
+        frame.localhost.SetValue("127.0.0.1")
+    else:
+        frame.localhost.Enable(True)
+
+
+def run(e):
+    # wrapper for main to ensure is not frozen I guess
+    task = Thread(target=main)
+    task.setDaemon(True)
+    task.start()
+
+
+if __name__ == '__main__':
+    console_title = 'Program Crashed! Here are the details'  # this is there for now to redirect any errors
+    app = wx.App(useBestVisual=True)
+    frame = Frame(None)
+    app.SetTopWindow(frame)
+    # set where the uncaught errors should be displayed
+    console = wx.PyOnDemandOutputWindow(console_title)
+    console.SetParent(frame)
+    # sys.stderr = console
+    frame.SetTitle("ECE-SSH_dev_1.1")
+    frame.run.Bind(wx.EVT_BUTTON, run)
+    frame.Bind(wx.EVT_CHECKBOX, on_chk)
+    frame.Show()
+    app.MainLoop()
+
+    # MAGIC_USERNAME_KEY = 'im_the_magic_username_key'
+    #
+    # # the service is just a namespace for your app
+    # service_id = 'IM_YOUR_APP!'
+    #
+    # username = 'dustin'
+    #
+    # # save password
+    # keyring.set_password(service_id, username, "password")
+    #
+    # # optionally, abuse `set_password` to save username onto keyring
+    # # we're just using some known magic string in the username field
+    # keyring.set_password(service_id, MAGIC_USERNAME_KEY, username)
+    # # username = keyring.get_password(service_id, MAGIC_USERNAME_KEY)
+    # # password = keyring.get_password(service_id, username)
+    # # print(username, password)

ui.py

@@ -0,0 +1,127 @@
+# -*- coding: utf-8 -*- 
+
+###########################################################################
+## Python code generated with wxFormBuilder (version Jun 17 2015)
+## http://www.wxformbuilder.org/
+##
+## PLEASE DO "NOT" EDIT THIS FILE!
+###########################################################################
+
+import wx
+import wx.xrc
+
+###########################################################################
+## Class Frame
+###########################################################################
+
+class Frame ( wx.Frame ):
+	
+	def __init__( self, parent ):
+		wx.Frame.__init__ ( self, parent, id = wx.ID_ANY, title = wx.EmptyString, pos = wx.DefaultPosition, size = wx.Size( 343,295 ), style = wx.DEFAULT_FRAME_STYLE )
+		
+		self.SetSizeHintsSz( wx.Size( 300,274 ), wx.DefaultSize )
+		self.SetForegroundColour( wx.SystemSettings.GetColour( wx.SYS_COLOUR_BTNTEXT ) )
+		self.SetBackgroundColour( wx.SystemSettings.GetColour( wx.SYS_COLOUR_WINDOW ) )
+		
+		bSizer1 = wx.BoxSizer( wx.VERTICAL )
+		
+		bSizer1.SetMinSize( wx.Size( 372,284 ) ) 
+		id_field = wx.FlexGridSizer( 3, 2, 0, 0 )
+		id_field.SetFlexibleDirection( wx.BOTH )
+		id_field.SetNonFlexibleGrowMode( wx.FLEX_GROWMODE_ALL )
+		
+		self.netio_prompt = wx.StaticText( self, wx.ID_ANY, u"UW Net-ID", wx.DefaultPosition, wx.DefaultSize, 0 )
+		self.netio_prompt.Wrap( -1 )
+		id_field.Add( self.netio_prompt, 0, wx.ALIGN_RIGHT|wx.ALL, 5 )
+		
+		self.net_id = wx.TextCtrl( self, wx.ID_ANY, wx.EmptyString, wx.DefaultPosition, wx.DefaultSize, 0|wx.FULL_REPAINT_ON_RESIZE|wx.WANTS_CHARS )
+		self.net_id.SetToolTipString( u"Your UW Net ID, WITHOUT @uw.edu" )
+		
+		id_field.Add( self.net_id, 0, wx.ALL|wx.ALIGN_CENTER_HORIZONTAL|wx.EXPAND, 5 )
+		
+		self.password_promot = wx.StaticText( self, wx.ID_ANY, u"Password", wx.DefaultPosition, wx.DefaultSize, 0 )
+		self.password_promot.Wrap( -1 )
+		id_field.Add( self.password_promot, 0, wx.ALL|wx.ALIGN_RIGHT, 5 )
+		
+		self.password = wx.TextCtrl( self, wx.ID_ANY, wx.EmptyString, wx.DefaultPosition, wx.DefaultSize, wx.TE_PASSWORD|wx.FULL_REPAINT_ON_RESIZE )
+		self.password.SetToolTipString( u"The password you use to login MyUW/MyPlan/Canvas and stuff at UW" )
+		
+		id_field.Add( self.password, 0, wx.ALL, 5 )
+		
+		self.vncPassword_prompt1 = wx.StaticText( self, wx.ID_ANY, u"VNC Password", wx.DefaultPosition, wx.DefaultSize, 0 )
+		self.vncPassword_prompt1.Wrap( -1 )
+		id_field.Add( self.vncPassword_prompt1, 0, wx.ALL|wx.ALIGN_RIGHT, 5 )
+		
+		self.vnc_passwd = wx.TextCtrl( self, wx.ID_ANY, wx.EmptyString, wx.DefaultPosition, wx.DefaultSize, wx.TE_PASSWORD|wx.FULL_REPAINT_ON_RESIZE )
+		self.vnc_passwd.SetToolTipString( u"Password you set for your VNC session. If you forgot or don't know or your first time using the ECE remote linux, just type in a password you would like to set/reset" )
+		
+		id_field.Add( self.vnc_passwd, 0, wx.ALL, 5 )
+		
+		
+		bSizer1.Add( id_field, 1, wx.ALIGN_CENTER_HORIZONTAL, 0 )
+		
+		inputArea = wx.GridBagSizer( 0, 0 )
+		inputArea.SetFlexibleDirection( wx.BOTH )
+		inputArea.SetNonFlexibleGrowMode( wx.FLEX_GROWMODE_SPECIFIED )
+		
+		self.localhos_prompt = wx.StaticText( self, wx.ID_ANY, u"Local IP", wx.DefaultPosition, wx.DefaultSize, 0 )
+		self.localhos_prompt.Wrap( -1 )
+		inputArea.Add( self.localhos_prompt, wx.GBPosition( 4, 0 ), wx.GBSpan( 1, 1 ), wx.ALL|wx.ALIGN_RIGHT|wx.ALIGN_CENTER_VERTICAL, 5 )
+		
+		self.localhost = wx.TextCtrl( self, wx.ID_ANY, u"127.0.0.1", wx.DefaultPosition, wx.DefaultSize, 0 )
+		self.localhost.Enable( False )
+		self.localhost.SetToolTipString( u"ip address on your computer that the linux server's data will sent to. Normally you won't need to worry about this one" )
+		
+		inputArea.Add( self.localhost, wx.GBPosition( 4, 1 ), wx.GBSpan( 1, 1 ), wx.ALL|wx.ALIGN_CENTER_VERTICAL, 5 )
+		
+		self.localhost_ck = wx.CheckBox( self, wx.ID_ANY, u"Use localhost", wx.DefaultPosition, wx.DefaultSize, 0 )
+		self.localhost_ck.SetValue(True) 
+		inputArea.Add( self.localhost_ck, wx.GBPosition( 3, 1 ), wx.GBSpan( 1, 1 ), wx.ALIGN_CENTER_VERTICAL, 5 )
+		
+		
+		bSizer1.Add( inputArea, 0, wx.ALIGN_CENTER|wx.ALL, 5 )
+		
+		gbSizer6 = wx.GridBagSizer( 0, 0 )
+		gbSizer6.SetFlexibleDirection( wx.BOTH )
+		gbSizer6.SetNonFlexibleGrowMode( wx.FLEX_GROWMODE_SPECIFIED )
+		
+		self.host_prompt = wx.StaticText( self, wx.ID_ANY, u"Server", wx.DefaultPosition, wx.DefaultSize, 0 )
+		self.host_prompt.Wrap( -1 )
+		gbSizer6.Add( self.host_prompt, wx.GBPosition( 0, 0 ), wx.GBSpan( 1, 1 ), wx.ALL, 5 )
+		
+		hostChoices = [ u"linuxsrv01.ece.uw.edu", u"linux-lab-041.ece.uw.edu", u"linux-lab-042.ece.uw.edu", u"linux-lab-043.ece.uw.edu", u"linux-lab-044.ece.uw.edu", u"linux-lab-045.ece.uw.edu", u"linux-lab-046.ece.uw.edu", u"linux-lab-047.ece.uw.edu", u"linux-lab-048.ece.uw.edu", u"linux-lab-049.ece.uw.edu", u"linux-lab-050.ece.uw.edu", u"linux-lab-051.ece.uw.edu", u"linux-lab-052.ece.uw.edu", u"linux-lab-054.ece.uw.edu", u"linux-lab-055.ece.uw.edu", u"linux-lab-056.ece.uw.edu", u"linux-lab-057.ece.uw.edu", u"linux-lab-058.ece.uw.edu", u"linux-lab-059.ece.uw.edu", u"linux-lab-060.ece.uw.edu", u"linux-lab-061.ece.uw.edu", u"linux-lab-062.ece.uw.edu", u"linux-lab-063.ece.uw.edu", u"linux-lab-064.ece.uw.edu", u"linux-lab-065.ece.uw.edu", u"linux-lab-066.ece.uw.edu", u"linux-lab-067.ece.uw.edu", u"linux-lab-069.ece.uw.edu", u"linux-lab-070.ece.uw.edu", u"linux-lab-071.ece.uw.edu", u"linux-lab-072.ece.uw.edu", u"linux-lab-073.ece.uw.edu", u"linux-lab-074.ece.uw.edu", u"linux-lab-075.ece.uw.edu", u"linux-lab-076.ece.uw.edu", u"linux-lab-077.ece.uw.edu", u"linux-lab-078.ece.uw.edu", u"linux-lab-079.ece.uw.edu", u"linux-lab-080.ece.uw.edu", u"linux-lab-078.ece.uw.edu", u"linux-lab-079.ece.uw.edu" ]
+		self.host = wx.ComboBox( self, wx.ID_ANY, wx.EmptyString, wx.DefaultPosition, wx.DefaultSize, hostChoices, 0 )
+		self.host.SetSelection( 0 )
+		gbSizer6.Add( self.host, wx.GBPosition( 0, 1 ), wx.GBSpan( 1, 1 ), wx.ALL, 5 )
+		
+		
+		bSizer1.Add( gbSizer6, 0, wx.ALIGN_CENTER_HORIZONTAL, 5 )
+		
+		self.run = wx.Button( self, wx.ID_ANY, u"RUN", wx.DefaultPosition, wx.DefaultSize, 0 )
+		bSizer1.Add( self.run, 0, wx.ALIGN_CENTER_HORIZONTAL, 5 )
+		
+		gbSizer8 = wx.GridBagSizer( 0, 0 )
+		gbSizer8.SetFlexibleDirection( wx.BOTH )
+		gbSizer8.SetNonFlexibleGrowMode( wx.FLEX_GROWMODE_SPECIFIED )
+		
+		self.kill_when_exit = wx.CheckBox( self, wx.ID_ANY, u"\"kill\" process when exit", wx.DefaultPosition, wx.DefaultSize, 0 )
+		self.kill_when_exit.SetValue(True) 
+		gbSizer8.Add( self.kill_when_exit, wx.GBPosition( 0, 0 ), wx.GBSpan( 1, 1 ), wx.ALL|wx.ALIGN_CENTER_HORIZONTAL, 5 )
+		
+		self.status = wx.StaticText( self, wx.ID_ANY, u"Click 'RUN' to begin, hover over any boxes to show hints", wx.DefaultPosition, wx.DefaultSize, wx.ALIGN_CENTRE )
+		self.status.Wrap( -1 )
+		gbSizer8.Add( self.status, wx.GBPosition( 1, 0 ), wx.GBSpan( 1, 1 ), wx.ALIGN_CENTER_HORIZONTAL|wx.ALIGN_CENTER_VERTICAL, 5 )
+		
+		
+		bSizer1.Add( gbSizer8, 0, wx.ALIGN_CENTER_HORIZONTAL, 5 )
+		
+		
+		self.SetSizer( bSizer1 )
+		self.Layout()
+		
+		self.Centre( wx.BOTH )
+	
+	def __del__( self ):
+		pass
+	
+

venv/Lib/site-packages/_distutils_hack/__init__.py

@@ -0,0 +1,222 @@
+# don't import any costly modules
+import sys
+import os
+
+
+is_pypy = '__pypy__' in sys.builtin_module_names
+
+
+def warn_distutils_present():
+    if 'distutils' not in sys.modules:
+        return
+    if is_pypy and sys.version_info < (3, 7):
+        # PyPy for 3.6 unconditionally imports distutils, so bypass the warning
+        # https://foss.heptapod.net/pypy/pypy/-/blob/be829135bc0d758997b3566062999ee8b23872b4/lib-python/3/site.py#L250
+        return
+    import warnings
+
+    warnings.warn(
+        "Distutils was imported before Setuptools, but importing Setuptools "
+        "also replaces the `distutils` module in `sys.modules`. This may lead "
+        "to undesirable behaviors or errors. To avoid these issues, avoid "
+        "using distutils directly, ensure that setuptools is installed in the "
+        "traditional way (e.g. not an editable install), and/or make sure "
+        "that setuptools is always imported before distutils."
+    )
+
+
+def clear_distutils():
+    if 'distutils' not in sys.modules:
+        return
+    import warnings
+
+    warnings.warn("Setuptools is replacing distutils.")
+    mods = [
+        name
+        for name in sys.modules
+        if name == "distutils" or name.startswith("distutils.")
+    ]
+    for name in mods:
+        del sys.modules[name]
+
+
+def enabled():
+    """
+    Allow selection of distutils by environment variable.
+    """
+    which = os.environ.get('SETUPTOOLS_USE_DISTUTILS', 'local')
+    return which == 'local'
+
+
+def ensure_local_distutils():
+    import importlib
+
+    clear_distutils()
+
+    # With the DistutilsMetaFinder in place,
+    # perform an import to cause distutils to be
+    # loaded from setuptools._distutils. Ref #2906.
+    with shim():
+        importlib.import_module('distutils')
+
+    # check that submodules load as expected
+    core = importlib.import_module('distutils.core')
+    assert '_distutils' in core.__file__, core.__file__
+    assert 'setuptools._distutils.log' not in sys.modules
+
+
+def do_override():
+    """
+    Ensure that the local copy of distutils is preferred over stdlib.
+
+    See https://github.com/pypa/setuptools/issues/417#issuecomment-392298401
+    for more motivation.
+    """
+    if enabled():
+        warn_distutils_present()
+        ensure_local_distutils()
+
+
+class _TrivialRe:
+    def __init__(self, *patterns):
+        self._patterns = patterns
+
+    def match(self, string):
+        return all(pat in string for pat in self._patterns)
+
+
+class DistutilsMetaFinder:
+    def find_spec(self, fullname, path, target=None):
+        # optimization: only consider top level modules and those
+        # found in the CPython test suite.
+        if path is not None and not fullname.startswith('test.'):
+            return
+
+        method_name = 'spec_for_{fullname}'.format(**locals())
+        method = getattr(self, method_name, lambda: None)
+        return method()
+
+    def spec_for_distutils(self):
+        if self.is_cpython():
+            return
+
+        import importlib
+        import importlib.abc
+        import importlib.util
+
+        try:
+            mod = importlib.import_module('setuptools._distutils')
+        except Exception:
+            # There are a couple of cases where setuptools._distutils
+            # may not be present:
+            # - An older Setuptools without a local distutils is
+            #   taking precedence. Ref #2957.
+            # - Path manipulation during sitecustomize removes
+            #   setuptools from the path but only after the hook
+            #   has been loaded. Ref #2980.
+            # In either case, fall back to stdlib behavior.
+            return
+
+        class DistutilsLoader(importlib.abc.Loader):
+            def create_module(self, spec):
+                mod.__name__ = 'distutils'
+                return mod
+
+            def exec_module(self, module):
+                pass
+
+        return importlib.util.spec_from_loader(
+            'distutils', DistutilsLoader(), origin=mod.__file__
+        )
+
+    @staticmethod
+    def is_cpython():
+        """
+        Suppress supplying distutils for CPython (build and tests).
+        Ref #2965 and #3007.
+        """
+        return os.path.isfile('pybuilddir.txt')
+
+    def spec_for_pip(self):
+        """
+        Ensure stdlib distutils when running under pip.
+        See pypa/pip#8761 for rationale.
+        """
+        if self.pip_imported_during_build():
+            return
+        clear_distutils()
+        self.spec_for_distutils = lambda: None
+
+    @classmethod
+    def pip_imported_during_build(cls):
+        """
+        Detect if pip is being imported in a build script. Ref #2355.
+        """
+        import traceback
+
+        return any(
+            cls.frame_file_is_setup(frame) for frame, line in traceback.walk_stack(None)
+        )
+
+    @staticmethod
+    def frame_file_is_setup(frame):
+        """
+        Return True if the indicated frame suggests a setup.py file.
+        """
+        # some frames may not have __file__ (#2940)
+        return frame.f_globals.get('__file__', '').endswith('setup.py')
+
+    def spec_for_sensitive_tests(self):
+        """
+        Ensure stdlib distutils when running select tests under CPython.
+
+        python/cpython#91169
+        """
+        clear_distutils()
+        self.spec_for_distutils = lambda: None
+
+    sensitive_tests = (
+        [
+            'test.test_distutils',
+            'test.test_peg_generator',
+            'test.test_importlib',
+        ]
+        if sys.version_info < (3, 10)
+        else [
+            'test.test_distutils',
+        ]
+    )
+
+
+for name in DistutilsMetaFinder.sensitive_tests:
+    setattr(
+        DistutilsMetaFinder,
+        f'spec_for_{name}',
+        DistutilsMetaFinder.spec_for_sensitive_tests,
+    )
+
+
+DISTUTILS_FINDER = DistutilsMetaFinder()
+
+
+def add_shim():
+    DISTUTILS_FINDER in sys.meta_path or insert_shim()
+
+
+class shim:
+    def __enter__(self):
+        insert_shim()
+
+    def __exit__(self, exc, value, tb):
+        remove_shim()
+
+
+def insert_shim():
+    sys.meta_path.insert(0, DISTUTILS_FINDER)
+
+
+def remove_shim():
+    try:
+        sys.meta_path.remove(DISTUTILS_FINDER)
+    except ValueError:
+        pass

venv/Lib/site-packages/_distutils_hack/override.py

@@ -0,0 +1 @@
+__import__('_distutils_hack').do_override()

venv/Lib/site-packages/cffi/__init__.py

@@ -0,0 +1,14 @@
+__all__ = ['FFI', 'VerificationError', 'VerificationMissing', 'CDefError',
+           'FFIError']
+
+from .api import FFI
+from .error import CDefError, FFIError, VerificationError, VerificationMissing
+from .error import PkgConfigError
+
+__version__ = "1.15.1"
+__version_info__ = (1, 15, 1)
+
+# The verifier module file names are based on the CRC32 of a string that
+# contains the following version number.  It may be older than __version__
+# if nothing is clearly incompatible.
+__version_verifier_modules__ = "0.8.6"

venv/Lib/site-packages/cffi/api.py

@@ -0,0 +1,965 @@
+import sys, types
+from .lock import allocate_lock
+from .error import CDefError
+from . import model
+
+try:
+    callable
+except NameError:
+    # Python 3.1
+    from collections import Callable
+    callable = lambda x: isinstance(x, Callable)
+
+try:
+    basestring
+except NameError:
+    # Python 3.x
+    basestring = str
+
+_unspecified = object()
+
+
+
+class FFI(object):
+    r'''
+    The main top-level class that you instantiate once, or once per module.
+
+    Example usage:
+
+        ffi = FFI()
+        ffi.cdef("""
+            int printf(const char *, ...);
+        """)
+
+        C = ffi.dlopen(None)   # standard library
+        -or-
+        C = ffi.verify()  # use a C compiler: verify the decl above is right
+
+        C.printf("hello, %s!\n", ffi.new("char[]", "world"))
+    '''
+
+    def __init__(self, backend=None):
+        """Create an FFI instance.  The 'backend' argument is used to
+        select a non-default backend, mostly for tests.
+        """
+        if backend is None:
+            # You need PyPy (>= 2.0 beta), or a CPython (>= 2.6) with
+            # _cffi_backend.so compiled.
+            import _cffi_backend as backend
+            from . import __version__
+            if backend.__version__ != __version__:
+                # bad version!  Try to be as explicit as possible.
+                if hasattr(backend, '__file__'):
+                    # CPython
+                    raise Exception("Version mismatch: this is the 'cffi' package version %s, located in %r.  When we import the top-level '_cffi_backend' extension module, we get version %s, located in %r.  The two versions should be equal; check your installation." % (
+                        __version__, __file__,
+                        backend.__version__, backend.__file__))
+                else:
+                    # PyPy
+                    raise Exception("Version mismatch: this is the 'cffi' package version %s, located in %r.  This interpreter comes with a built-in '_cffi_backend' module, which is version %s.  The two versions should be equal; check your installation." % (
+                        __version__, __file__, backend.__version__))
+            # (If you insist you can also try to pass the option
+            # 'backend=backend_ctypes.CTypesBackend()', but don't
+            # rely on it!  It's probably not going to work well.)
+
+        from . import cparser
+        self._backend = backend
+        self._lock = allocate_lock()
+        self._parser = cparser.Parser()
+        self._cached_btypes = {}
+        self._parsed_types = types.ModuleType('parsed_types').__dict__
+        self._new_types = types.ModuleType('new_types').__dict__
+        self._function_caches = []
+        self._libraries = []
+        self._cdefsources = []
+        self._included_ffis = []
+        self._windows_unicode = None
+        self._init_once_cache = {}
+        self._cdef_version = None
+        self._embedding = None
+        self._typecache = model.get_typecache(backend)
+        if hasattr(backend, 'set_ffi'):
+            backend.set_ffi(self)
+        for name in list(backend.__dict__):
+            if name.startswith('RTLD_'):
+                setattr(self, name, getattr(backend, name))
+        #
+        with self._lock:
+            self.BVoidP = self._get_cached_btype(model.voidp_type)
+            self.BCharA = self._get_cached_btype(model.char_array_type)
+        if isinstance(backend, types.ModuleType):
+            # _cffi_backend: attach these constants to the class
+            if not hasattr(FFI, 'NULL'):
+                FFI.NULL = self.cast(self.BVoidP, 0)
+                FFI.CData, FFI.CType = backend._get_types()
+        else:
+            # ctypes backend: attach these constants to the instance
+            self.NULL = self.cast(self.BVoidP, 0)
+            self.CData, self.CType = backend._get_types()
+        self.buffer = backend.buffer
+
+    def cdef(self, csource, override=False, packed=False, pack=None):
+        """Parse the given C source.  This registers all declared functions,
+        types, and global variables.  The functions and global variables can
+        then be accessed via either 'ffi.dlopen()' or 'ffi.verify()'.
+        The types can be used in 'ffi.new()' and other functions.
+        If 'packed' is specified as True, all structs declared inside this
+        cdef are packed, i.e. laid out without any field alignment at all.
+        Alternatively, 'pack' can be a small integer, and requests for
+        alignment greater than that are ignored (pack=1 is equivalent to
+        packed=True).
+        """
+        self._cdef(csource, override=override, packed=packed, pack=pack)
+
+    def embedding_api(self, csource, packed=False, pack=None):
+        self._cdef(csource, packed=packed, pack=pack, dllexport=True)
+        if self._embedding is None:
+            self._embedding = ''
+
+    def _cdef(self, csource, override=False, **options):
+        if not isinstance(csource, str):    # unicode, on Python 2
+            if not isinstance(csource, basestring):
+                raise TypeError("cdef() argument must be a string")
+            csource = csource.encode('ascii')
+        with self._lock:
+            self._cdef_version = object()
+            self._parser.parse(csource, override=override, **options)
+            self._cdefsources.append(csource)
+            if override:
+                for cache in self._function_caches:
+                    cache.clear()
+            finishlist = self._parser._recomplete
+            if finishlist:
+                self._parser._recomplete = []
+                for tp in finishlist:
+                    tp.finish_backend_type(self, finishlist)
+
+    def dlopen(self, name, flags=0):
+        """Load and return a dynamic library identified by 'name'.
+        The standard C library can be loaded by passing None.
+        Note that functions and types declared by 'ffi.cdef()' are not
+        linked to a particular library, just like C headers; in the
+        library we only look for the actual (untyped) symbols.
+        """
+        if not (isinstance(name, basestring) or
+                name is None or
+                isinstance(name, self.CData)):
+            raise TypeError("dlopen(name): name must be a file name, None, "
+                            "or an already-opened 'void *' handle")
+        with self._lock:
+            lib, function_cache = _make_ffi_library(self, name, flags)
+            self._function_caches.append(function_cache)
+            self._libraries.append(lib)
+        return lib
+
+    def dlclose(self, lib):
+        """Close a library obtained with ffi.dlopen().  After this call,
+        access to functions or variables from the library will fail
+        (possibly with a segmentation fault).
+        """
+        type(lib).__cffi_close__(lib)
+
+    def _typeof_locked(self, cdecl):
+        # call me with the lock!
+        key = cdecl
+        if key in self._parsed_types:
+            return self._parsed_types[key]
+        #
+        if not isinstance(cdecl, str):    # unicode, on Python 2
+            cdecl = cdecl.encode('ascii')
+        #
+        type = self._parser.parse_type(cdecl)
+        really_a_function_type = type.is_raw_function
+        if really_a_function_type:
+            type = type.as_function_pointer()
+        btype = self._get_cached_btype(type)
+        result = btype, really_a_function_type
+        self._parsed_types[key] = result
+        return result
+
+    def _typeof(self, cdecl, consider_function_as_funcptr=False):
+        # string -> ctype object
+        try:
+            result = self._parsed_types[cdecl]
+        except KeyError:
+            with self._lock:
+                result = self._typeof_locked(cdecl)
+        #
+        btype, really_a_function_type = result
+        if really_a_function_type and not consider_function_as_funcptr:
+            raise CDefError("the type %r is a function type, not a "
+                            "pointer-to-function type" % (cdecl,))
+        return btype
+
+    def typeof(self, cdecl):
+        """Parse the C type given as a string and return the
+        corresponding <ctype> object.
+        It can also be used on 'cdata' instance to get its C type.
+        """
+        if isinstance(cdecl, basestring):
+            return self._typeof(cdecl)
+        if isinstance(cdecl, self.CData):
+            return self._backend.typeof(cdecl)
+        if isinstance(cdecl, types.BuiltinFunctionType):
+            res = _builtin_function_type(cdecl)
+            if res is not None:
+                return res
+        if (isinstance(cdecl, types.FunctionType)
+                and hasattr(cdecl, '_cffi_base_type')):
+            with self._lock:
+                return self._get_cached_btype(cdecl._cffi_base_type)
+        raise TypeError(type(cdecl))
+
+    def sizeof(self, cdecl):
+        """Return the size in bytes of the argument.  It can be a
+        string naming a C type, or a 'cdata' instance.
+        """
+        if isinstance(cdecl, basestring):
+            BType = self._typeof(cdecl)
+            return self._backend.sizeof(BType)
+        else:
+            return self._backend.sizeof(cdecl)
+
+    def alignof(self, cdecl):
+        """Return the natural alignment size in bytes of the C type
+        given as a string.
+        """
+        if isinstance(cdecl, basestring):
+            cdecl = self._typeof(cdecl)
+        return self._backend.alignof(cdecl)
+
+    def offsetof(self, cdecl, *fields_or_indexes):
+        """Return the offset of the named field inside the given
+        structure or array, which must be given as a C type name.
+        You can give several field names in case of nested structures.
+        You can also give numeric values which correspond to array
+        items, in case of an array type.
+        """
+        if isinstance(cdecl, basestring):
+            cdecl = self._typeof(cdecl)
+        return self._typeoffsetof(cdecl, *fields_or_indexes)[1]
+
+    def new(self, cdecl, init=None):
+        """Allocate an instance according to the specified C type and
+        return a pointer to it.  The specified C type must be either a
+        pointer or an array: ``new('X *')`` allocates an X and returns
+        a pointer to it, whereas ``new('X[n]')`` allocates an array of
+        n X'es and returns an array referencing it (which works
+        mostly like a pointer, like in C).  You can also use
+        ``new('X[]', n)`` to allocate an array of a non-constant
+        length n.
+
+        The memory is initialized following the rules of declaring a
+        global variable in C: by default it is zero-initialized, but
+        an explicit initializer can be given which can be used to
+        fill all or part of the memory.
+
+        When the returned <cdata> object goes out of scope, the memory
+        is freed.  In other words the returned <cdata> object has
+        ownership of the value of type 'cdecl' that it points to.  This
+        means that the raw data can be used as long as this object is
+        kept alive, but must not be used for a longer time.  Be careful
+        about that when copying the pointer to the memory somewhere
+        else, e.g. into another structure.
+        """
+        if isinstance(cdecl, basestring):
+            cdecl = self._typeof(cdecl)
+        return self._backend.newp(cdecl, init)
+
+    def new_allocator(self, alloc=None, free=None,
+                      should_clear_after_alloc=True):
+        """Return a new allocator, i.e. a function that behaves like ffi.new()
+        but uses the provided low-level 'alloc' and 'free' functions.
+
+        'alloc' is called with the size as argument.  If it returns NULL, a
+        MemoryError is raised.  'free' is called with the result of 'alloc'
+        as argument.  Both can be either Python function or directly C
+        functions.  If 'free' is None, then no free function is called.
+        If both 'alloc' and 'free' are None, the default is used.
+
+        If 'should_clear_after_alloc' is set to False, then the memory
+        returned by 'alloc' is assumed to be already cleared (or you are
+        fine with garbage); otherwise CFFI will clear it.
+        """
+        compiled_ffi = self._backend.FFI()
+        allocator = compiled_ffi.new_allocator(alloc, free,
+                                               should_clear_after_alloc)
+        def allocate(cdecl, init=None):
+            if isinstance(cdecl, basestring):
+                cdecl = self._typeof(cdecl)
+            return allocator(cdecl, init)
+        return allocate
+
+    def cast(self, cdecl, source):
+        """Similar to a C cast: returns an instance of the named C
+        type initialized with the given 'source'.  The source is
+        casted between integers or pointers of any type.
+        """
+        if isinstance(cdecl, basestring):
+            cdecl = self._typeof(cdecl)
+        return self._backend.cast(cdecl, source)
+
+    def string(self, cdata, maxlen=-1):
+        """Return a Python string (or unicode string) from the 'cdata'.
+        If 'cdata' is a pointer or array of characters or bytes, returns
+        the null-terminated string.  The returned string extends until
+        the first null character, or at most 'maxlen' characters.  If
+        'cdata' is an array then 'maxlen' defaults to its length.
+
+        If 'cdata' is a pointer or array of wchar_t, returns a unicode
+        string following the same rules.
+
+        If 'cdata' is a single character or byte or a wchar_t, returns
+        it as a string or unicode string.
+
+        If 'cdata' is an enum, returns the value of the enumerator as a
+        string, or 'NUMBER' if the value is out of range.
+        """
+        return self._backend.string(cdata, maxlen)
+
+    def unpack(self, cdata, length):
+        """Unpack an array of C data of the given length,
+        returning a Python string/unicode/list.
+
+        If 'cdata' is a pointer to 'char', returns a byte string.
+        It does not stop at the first null.  This is equivalent to:
+        ffi.buffer(cdata, length)[:]
+
+        If 'cdata' is a pointer to 'wchar_t', returns a unicode string.
+        'length' is measured in wchar_t's; it is not the size in bytes.
+
+        If 'cdata' is a pointer to anything else, returns a list of
+        'length' items.  This is a faster equivalent to:
+        [cdata[i] for i in range(length)]
+        """
+        return self._backend.unpack(cdata, length)
+
+   #def buffer(self, cdata, size=-1):
+   #    """Return a read-write buffer object that references the raw C data
+   #    pointed to by the given 'cdata'.  The 'cdata' must be a pointer or
+   #    an array.  Can be passed to functions expecting a buffer, or directly
+   #    manipulated with:
+   #
+   #        buf[:]          get a copy of it in a regular string, or
+   #        buf[idx]        as a single character
+   #        buf[:] = ...
+   #        buf[idx] = ...  change the content
+   #    """
+   #    note that 'buffer' is a type, set on this instance by __init__
+
+    def from_buffer(self, cdecl, python_buffer=_unspecified,
+                    require_writable=False):
+        """Return a cdata of the given type pointing to the data of the
+        given Python object, which must support the buffer interface.
+        Note that this is not meant to be used on the built-in types
+        str or unicode (you can build 'char[]' arrays explicitly)
+        but only on objects containing large quantities of raw data
+        in some other format, like 'array.array' or numpy arrays.
+
+        The first argument is optional and default to 'char[]'.
+        """
+        if python_buffer is _unspecified:
+            cdecl, python_buffer = self.BCharA, cdecl
+        elif isinstance(cdecl, basestring):
+            cdecl = self._typeof(cdecl)
+        return self._backend.from_buffer(cdecl, python_buffer,
+                                         require_writable)
+
+    def memmove(self, dest, src, n):
+        """ffi.memmove(dest, src, n) copies n bytes of memory from src to dest.
+
+        Like the C function memmove(), the memory areas may overlap;
+        apart from that it behaves like the C function memcpy().
+
+        'src' can be any cdata ptr or array, or any Python buffer object.
+        'dest' can be any cdata ptr or array, or a writable Python buffer
+        object.  The size to copy, 'n', is always measured in bytes.
+
+        Unlike other methods, this one supports all Python buffer including
+        byte strings and bytearrays---but it still does not support
+        non-contiguous buffers.
+        """
+        return self._backend.memmove(dest, src, n)
+
+    def callback(self, cdecl, python_callable=None, error=None, onerror=None):
+        """Return a callback object or a decorator making such a
+        callback object.  'cdecl' must name a C function pointer type.
+        The callback invokes the specified 'python_callable' (which may
+        be provided either directly or via a decorator).  Important: the
+        callback object must be manually kept alive for as long as the
+        callback may be invoked from the C level.
+        """
+        def callback_decorator_wrap(python_callable):
+            if not callable(python_callable):
+                raise TypeError("the 'python_callable' argument "
+                                "is not callable")
+            return self._backend.callback(cdecl, python_callable,
+                                          error, onerror)
+        if isinstance(cdecl, basestring):
+            cdecl = self._typeof(cdecl, consider_function_as_funcptr=True)
+        if python_callable is None:
+            return callback_decorator_wrap                # decorator mode
+        else:
+            return callback_decorator_wrap(python_callable)  # direct mode
+
+    def getctype(self, cdecl, replace_with=''):
+        """Return a string giving the C type 'cdecl', which may be itself
+        a string or a <ctype> object.  If 'replace_with' is given, it gives
+        extra text to append (or insert for more complicated C types), like
+        a variable name, or '*' to get actually the C type 'pointer-to-cdecl'.
+        """
+        if isinstance(cdecl, basestring):
+            cdecl = self._typeof(cdecl)
+        replace_with = replace_with.strip()
+        if (replace_with.startswith('*')
+                and '&[' in self._backend.getcname(cdecl, '&')):
+            replace_with = '(%s)' % replace_with
+        elif replace_with and not replace_with[0] in '[(':
+            replace_with = ' ' + replace_with
+        return self._backend.getcname(cdecl, replace_with)
+
+    def gc(self, cdata, destructor, size=0):
+        """Return a new cdata object that points to the same
+        data.  Later, when this new cdata object is garbage-collected,
+        'destructor(old_cdata_object)' will be called.
+
+        The optional 'size' gives an estimate of the size, used to
+        trigger the garbage collection more eagerly.  So far only used
+        on PyPy.  It tells the GC that the returned object keeps alive
+        roughly 'size' bytes of external memory.
+        """
+        return self._backend.gcp(cdata, destructor, size)
+
+    def _get_cached_btype(self, type):
+        assert self._lock.acquire(False) is False
+        # call me with the lock!
+        try:
+            BType = self._cached_btypes[type]
+        except KeyError:
+            finishlist = []
+            BType = type.get_cached_btype(self, finishlist)
+            for type in finishlist:
+                type.finish_backend_type(self, finishlist)
+        return BType
+
+    def verify(self, source='', tmpdir=None, **kwargs):
+        """Verify that the current ffi signatures compile on this
+        machine, and return a dynamic library object.  The dynamic
+        library can be used to call functions and access global
+        variables declared in this 'ffi'.  The library is compiled
+        by the C compiler: it gives you C-level API compatibility
+        (including calling macros).  This is unlike 'ffi.dlopen()',
+        which requires binary compatibility in the signatures.
+        """
+        from .verifier import Verifier, _caller_dir_pycache
+        #
+        # If set_unicode(True) was called, insert the UNICODE and
+        # _UNICODE macro declarations
+        if self._windows_unicode:
+            self._apply_windows_unicode(kwargs)
+        #
+        # Set the tmpdir here, and not in Verifier.__init__: it picks
+        # up the caller's directory, which we want to be the caller of
+        # ffi.verify(), as opposed to the caller of Veritier().
+        tmpdir = tmpdir or _caller_dir_pycache()
+        #
+        # Make a Verifier() and use it to load the library.
+        self.verifier = Verifier(self, source, tmpdir, **kwargs)
+        lib = self.verifier.load_library()
+        #
+        # Save the loaded library for keep-alive purposes, even
+        # if the caller doesn't keep it alive itself (it should).
+        self._libraries.append(lib)
+        return lib
+
+    def _get_errno(self):
+        return self._backend.get_errno()
+    def _set_errno(self, errno):
+        self._backend.set_errno(errno)
+    errno = property(_get_errno, _set_errno, None,
+                     "the value of 'errno' from/to the C calls")
+
+    def getwinerror(self, code=-1):
+        return self._backend.getwinerror(code)
+
+    def _pointer_to(self, ctype):
+        with self._lock:
+            return model.pointer_cache(self, ctype)
+
+    def addressof(self, cdata, *fields_or_indexes):
+        """Return the address of a <cdata 'struct-or-union'>.
+        If 'fields_or_indexes' are given, returns the address of that
+        field or array item in the structure or array, recursively in
+        case of nested structures.
+        """
+        try:
+            ctype = self._backend.typeof(cdata)
+        except TypeError:
+            if '__addressof__' in type(cdata).__dict__:
+                return type(cdata).__addressof__(cdata, *fields_or_indexes)
+            raise
+        if fields_or_indexes:
+            ctype, offset = self._typeoffsetof(ctype, *fields_or_indexes)
+        else:
+            if ctype.kind == "pointer":
+                raise TypeError("addressof(pointer)")
+            offset = 0
+        ctypeptr = self._pointer_to(ctype)
+        return self._backend.rawaddressof(ctypeptr, cdata, offset)
+
+    def _typeoffsetof(self, ctype, field_or_index, *fields_or_indexes):
+        ctype, offset = self._backend.typeoffsetof(ctype, field_or_index)
+        for field1 in fields_or_indexes:
+            ctype, offset1 = self._backend.typeoffsetof(ctype, field1, 1)
+            offset += offset1
+        return ctype, offset
+
+    def include(self, ffi_to_include):
+        """Includes the typedefs, structs, unions and enums defined
+        in another FFI instance.  Usage is similar to a #include in C,
+        where a part of the program might include types defined in
+        another part for its own usage.  Note that the include()
+        method has no effect on functions, constants and global
+        variables, which must anyway be accessed directly from the
+        lib object returned by the original FFI instance.
+        """
+        if not isinstance(ffi_to_include, FFI):
+            raise TypeError("ffi.include() expects an argument that is also of"
+                            " type cffi.FFI, not %r" % (
+                                type(ffi_to_include).__name__,))
+        if ffi_to_include is self:
+            raise ValueError("self.include(self)")
+        with ffi_to_include._lock:
+            with self._lock:
+                self._parser.include(ffi_to_include._parser)
+                self._cdefsources.append('[')
+                self._cdefsources.extend(ffi_to_include._cdefsources)
+                self._cdefsources.append(']')
+                self._included_ffis.append(ffi_to_include)
+
+    def new_handle(self, x):
+        return self._backend.newp_handle(self.BVoidP, x)
+
+    def from_handle(self, x):
+        return self._backend.from_handle(x)
+
+    def release(self, x):
+        self._backend.release(x)
+
+    def set_unicode(self, enabled_flag):
+        """Windows: if 'enabled_flag' is True, enable the UNICODE and
+        _UNICODE defines in C, and declare the types like TCHAR and LPTCSTR
+        to be (pointers to) wchar_t.  If 'enabled_flag' is False,
+        declare these types to be (pointers to) plain 8-bit characters.
+        This is mostly for backward compatibility; you usually want True.
+        """
+        if self._windows_unicode is not None:
+            raise ValueError("set_unicode() can only be called once")
+        enabled_flag = bool(enabled_flag)
+        if enabled_flag:
+            self.cdef("typedef wchar_t TBYTE;"
+                      "typedef wchar_t TCHAR;"
+                      "typedef const wchar_t *LPCTSTR;"
+                      "typedef const wchar_t *PCTSTR;"
+                      "typedef wchar_t *LPTSTR;"
+                      "typedef wchar_t *PTSTR;"
+                      "typedef TBYTE *PTBYTE;"
+                      "typedef TCHAR *PTCHAR;")
+        else:
+            self.cdef("typedef char TBYTE;"
+                      "typedef char TCHAR;"
+                      "typedef const char *LPCTSTR;"
+                      "typedef const char *PCTSTR;"
+                      "typedef char *LPTSTR;"
+                      "typedef char *PTSTR;"
+                      "typedef TBYTE *PTBYTE;"
+                      "typedef TCHAR *PTCHAR;")
+        self._windows_unicode = enabled_flag
+
+    def _apply_windows_unicode(self, kwds):
+        defmacros = kwds.get('define_macros', ())
+        if not isinstance(defmacros, (list, tuple)):
+            raise TypeError("'define_macros' must be a list or tuple")
+        defmacros = list(defmacros) + [('UNICODE', '1'),
+                                       ('_UNICODE', '1')]
+        kwds['define_macros'] = defmacros
+
+    def _apply_embedding_fix(self, kwds):
+        # must include an argument like "-lpython2.7" for the compiler
+        def ensure(key, value):
+            lst = kwds.setdefault(key, [])
+            if value not in lst:
+                lst.append(value)
+        #
+        if '__pypy__' in sys.builtin_module_names:
+            import os
+            if sys.platform == "win32":
+                # we need 'libpypy-c.lib'.  Current distributions of
+                # pypy (>= 4.1) contain it as 'libs/python27.lib'.
+                pythonlib = "python{0[0]}{0[1]}".format(sys.version_info)
+                if hasattr(sys, 'prefix'):
+                    ensure('library_dirs', os.path.join(sys.prefix, 'libs'))
+            else:
+                # we need 'libpypy-c.{so,dylib}', which should be by
+                # default located in 'sys.prefix/bin' for installed
+                # systems.
+                if sys.version_info < (3,):
+                    pythonlib = "pypy-c"
+                else:
+                    pythonlib = "pypy3-c"
+                if hasattr(sys, 'prefix'):
+                    ensure('library_dirs', os.path.join(sys.prefix, 'bin'))
+            # On uninstalled pypy's, the libpypy-c is typically found in
+            # .../pypy/goal/.
+            if hasattr(sys, 'prefix'):
+                ensure('library_dirs', os.path.join(sys.prefix, 'pypy', 'goal'))
+        else:
+            if sys.platform == "win32":
+                template = "python%d%d"
+                if hasattr(sys, 'gettotalrefcount'):
+                    template += '_d'
+            else:
+                try:
+                    import sysconfig
+                except ImportError:    # 2.6
+                    from distutils import sysconfig
+                template = "python%d.%d"
+                if sysconfig.get_config_var('DEBUG_EXT'):
+                    template += sysconfig.get_config_var('DEBUG_EXT')
+            pythonlib = (template %
+                    (sys.hexversion >> 24, (sys.hexversion >> 16) & 0xff))
+            if hasattr(sys, 'abiflags'):
+                pythonlib += sys.abiflags
+        ensure('libraries', pythonlib)
+        if sys.platform == "win32":
+            ensure('extra_link_args', '/MANIFEST')
+
+    def set_source(self, module_name, source, source_extension='.c', **kwds):
+        import os
+        if hasattr(self, '_assigned_source'):
+            raise ValueError("set_source() cannot be called several times "
+                             "per ffi object")
+        if not isinstance(module_name, basestring):
+            raise TypeError("'module_name' must be a string")
+        if os.sep in module_name or (os.altsep and os.altsep in module_name):
+            raise ValueError("'module_name' must not contain '/': use a dotted "
+                             "name to make a 'package.module' location")
+        self._assigned_source = (str(module_name), source,
+                                 source_extension, kwds)
+
+    def set_source_pkgconfig(self, module_name, pkgconfig_libs, source,
+                             source_extension='.c', **kwds):
+        from . import pkgconfig
+        if not isinstance(pkgconfig_libs, list):
+            raise TypeError("the pkgconfig_libs argument must be a list "
+                            "of package names")
+        kwds2 = pkgconfig.flags_from_pkgconfig(pkgconfig_libs)
+        pkgconfig.merge_flags(kwds, kwds2)
+        self.set_source(module_name, source, source_extension, **kwds)
+
+    def distutils_extension(self, tmpdir='build', verbose=True):
+        from distutils.dir_util import mkpath
+        from .recompiler import recompile
+        #
+        if not hasattr(self, '_assigned_source'):
+            if hasattr(self, 'verifier'):     # fallback, 'tmpdir' ignored
+                return self.verifier.get_extension()
+            raise ValueError("set_source() must be called before"
+                             " distutils_extension()")
+        module_name, source, source_extension, kwds = self._assigned_source
+        if source is None:
+            raise TypeError("distutils_extension() is only for C extension "
+                            "modules, not for dlopen()-style pure Python "
+                            "modules")
+        mkpath(tmpdir)
+        ext, updated = recompile(self, module_name,
+                                 source, tmpdir=tmpdir, extradir=tmpdir,
+                                 source_extension=source_extension,
+                                 call_c_compiler=False, **kwds)
+        if verbose:
+            if updated:
+                sys.stderr.write("regenerated: %r\n" % (ext.sources[0],))
+            else:
+                sys.stderr.write("not modified: %r\n" % (ext.sources[0],))
+        return ext
+
+    def emit_c_code(self, filename):
+        from .recompiler import recompile
+        #
+        if not hasattr(self, '_assigned_source'):
+            raise ValueError("set_source() must be called before emit_c_code()")
+        module_name, source, source_extension, kwds = self._assigned_source
+        if source is None:
+            raise TypeError("emit_c_code() is only for C extension modules, "
+                            "not for dlopen()-style pure Python modules")
+        recompile(self, module_name, source,
+                  c_file=filename, call_c_compiler=False, **kwds)
+
+    def emit_python_code(self, filename):
+        from .recompiler import recompile
+        #
+        if not hasattr(self, '_assigned_source'):
+            raise ValueError("set_source() must be called before emit_c_code()")
+        module_name, source, source_extension, kwds = self._assigned_source
+        if source is not None:
+            raise TypeError("emit_python_code() is only for dlopen()-style "
+                            "pure Python modules, not for C extension modules")
+        recompile(self, module_name, source,
+                  c_file=filename, call_c_compiler=False, **kwds)
+
+    def compile(self, tmpdir='.', verbose=0, target=None, debug=None):
+        """The 'target' argument gives the final file name of the
+        compiled DLL.  Use '*' to force distutils' choice, suitable for
+        regular CPython C API modules.  Use a file name ending in '.*'
+        to ask for the system's default extension for dynamic libraries
+        (.so/.dll/.dylib).
+
+        The default is '*' when building a non-embedded C API extension,
+        and (module_name + '.*') when building an embedded library.
+        """
+        from .recompiler import recompile
+        #
+        if not hasattr(self, '_assigned_source'):
+            raise ValueError("set_source() must be called before compile()")
+        module_name, source, source_extension, kwds = self._assigned_source
+        return recompile(self, module_name, source, tmpdir=tmpdir,
+                         target=target, source_extension=source_extension,
+                         compiler_verbose=verbose, debug=debug, **kwds)
+
+    def init_once(self, func, tag):
+        # Read _init_once_cache[tag], which is either (False, lock) if
+        # we're calling the function now in some thread, or (True, result).
+        # Don't call setdefault() in most cases, to avoid allocating and
+        # immediately freeing a lock; but still use setdefaut() to avoid
+        # races.
+        try:
+            x = self._init_once_cache[tag]
+        except KeyError:
+            x = self._init_once_cache.setdefault(tag, (False, allocate_lock()))
+        # Common case: we got (True, result), so we return the result.
+        if x[0]:
+            return x[1]
+        # Else, it's a lock.  Acquire it to serialize the following tests.
+        with x[1]:
+            # Read again from _init_once_cache the current status.
+            x = self._init_once_cache[tag]
+            if x[0]:
+                return x[1]
+            # Call the function and store the result back.
+            result = func()
+            self._init_once_cache[tag] = (True, result)
+        return result
+
+    def embedding_init_code(self, pysource):
+        if self._embedding:
+            raise ValueError("embedding_init_code() can only be called once")
+        # fix 'pysource' before it gets dumped into the C file:
+        # - remove empty lines at the beginning, so it starts at "line 1"
+        # - dedent, if all non-empty lines are indented
+        # - check for SyntaxErrors
+        import re
+        match = re.match(r'\s*\n', pysource)
+        if match:
+            pysource = pysource[match.end():]
+        lines = pysource.splitlines() or ['']
+        prefix = re.match(r'\s*', lines[0]).group()
+        for i in range(1, len(lines)):
+            line = lines[i]
+            if line.rstrip():
+                while not line.startswith(prefix):
+                    prefix = prefix[:-1]
+        i = len(prefix)
+        lines = [line[i:]+'\n' for line in lines]
+        pysource = ''.join(lines)
+        #
+        compile(pysource, "cffi_init", "exec")
+        #
+        self._embedding = pysource
+
+    def def_extern(self, *args, **kwds):
+        raise ValueError("ffi.def_extern() is only available on API-mode FFI "
+                         "objects")
+
+    def list_types(self):
+        """Returns the user type names known to this FFI instance.
+        This returns a tuple containing three lists of names:
+        (typedef_names, names_of_structs, names_of_unions)
+        """
+        typedefs = []
+        structs = []
+        unions = []
+        for key in self._parser._declarations:
+            if key.startswith('typedef '):
+                typedefs.append(key[8:])
+            elif key.startswith('struct '):
+                structs.append(key[7:])
+            elif key.startswith('union '):
+                unions.append(key[6:])
+        typedefs.sort()
+        structs.sort()
+        unions.sort()
+        return (typedefs, structs, unions)
+
+
+def _load_backend_lib(backend, name, flags):
+    import os
+    if not isinstance(name, basestring):
+        if sys.platform != "win32" or name is not None:
+            return backend.load_library(name, flags)
+        name = "c"    # Windows: load_library(None) fails, but this works
+                      # on Python 2 (backward compatibility hack only)
+    first_error = None
+    if '.' in name or '/' in name or os.sep in name:
+        try:
+            return backend.load_library(name, flags)
+        except OSError as e:
+            first_error = e
+    import ctypes.util
+    path = ctypes.util.find_library(name)
+    if path is None:
+        if name == "c" and sys.platform == "win32" and sys.version_info >= (3,):
+            raise OSError("dlopen(None) cannot work on Windows for Python 3 "
+                          "(see http://bugs.python.org/issue23606)")
+        msg = ("ctypes.util.find_library() did not manage "
+               "to locate a library called %r" % (name,))
+        if first_error is not None:
+            msg = "%s.  Additionally, %s" % (first_error, msg)
+        raise OSError(msg)
+    return backend.load_library(path, flags)
+
+def _make_ffi_library(ffi, libname, flags):
+    backend = ffi._backend
+    backendlib = _load_backend_lib(backend, libname, flags)
+    #
+    def accessor_function(name):
+        key = 'function ' + name
+        tp, _ = ffi._parser._declarations[key]
+        BType = ffi._get_cached_btype(tp)
+        value = backendlib.load_function(BType, name)
+        library.__dict__[name] = value
+    #
+    def accessor_variable(name):
+        key = 'variable ' + name
+        tp, _ = ffi._parser._declarations[key]
+        BType = ffi._get_cached_btype(tp)
+        read_variable = backendlib.read_variable
+        write_variable = backendlib.write_variable
+        setattr(FFILibrary, name, property(
+            lambda self: read_variable(BType, name),
+            lambda self, value: write_variable(BType, name, value)))
+    #
+    def addressof_var(name):
+        try:
+            return addr_variables[name]
+        except KeyError:
+            with ffi._lock:
+                if name not in addr_variables:
+                    key = 'variable ' + name
+                    tp, _ = ffi._parser._declarations[key]
+                    BType = ffi._get_cached_btype(tp)
+                    if BType.kind != 'array':
+                        BType = model.pointer_cache(ffi, BType)
+                    p = backendlib.load_function(BType, name)
+                    addr_variables[name] = p
+            return addr_variables[name]
+    #
+    def accessor_constant(name):
+        raise NotImplementedError("non-integer constant '%s' cannot be "
+                                  "accessed from a dlopen() library" % (name,))
+    #
+    def accessor_int_constant(name):
+        library.__dict__[name] = ffi._parser._int_constants[name]
+    #
+    accessors = {}
+    accessors_version = [False]
+    addr_variables = {}
+    #
+    def update_accessors():
+        if accessors_version[0] is ffi._cdef_version:
+            return
+        #
+        for key, (tp, _) in ffi._parser._declarations.items():
+            if not isinstance(tp, model.EnumType):
+                tag, name = key.split(' ', 1)
+                if tag == 'function':
+                    accessors[name] = accessor_function
+                elif tag == 'variable':
+                    accessors[name] = accessor_variable
+                elif tag == 'constant':
+                    accessors[name] = accessor_constant
+            else:
+                for i, enumname in enumerate(tp.enumerators):
+                    def accessor_enum(name, tp=tp, i=i):
+                        tp.check_not_partial()
+                        library.__dict__[name] = tp.enumvalues[i]
+                    accessors[enumname] = accessor_enum
+        for name in ffi._parser._int_constants:
+            accessors.setdefault(name, accessor_int_constant)
+        accessors_version[0] = ffi._cdef_version
+    #
+    def make_accessor(name):
+        with ffi._lock:
+            if name in library.__dict__ or name in FFILibrary.__dict__:
+                return    # added by another thread while waiting for the lock
+            if name not in accessors:
+                update_accessors()
+                if name not in accessors:
+                    raise AttributeError(name)
+            accessors[name](name)
+    #
+    class FFILibrary(object):
+        def __getattr__(self, name):
+            make_accessor(name)
+            return getattr(self, name)
+        def __setattr__(self, name, value):
+            try:
+                property = getattr(self.__class__, name)
+            except AttributeError:
+                make_accessor(name)
+                setattr(self, name, value)
+            else:
+                property.__set__(self, value)
+        def __dir__(self):
+            with ffi._lock:
+                update_accessors()
+                return accessors.keys()
+        def __addressof__(self, name):
+            if name in library.__dict__:
+                return library.__dict__[name]
+            if name in FFILibrary.__dict__:
+                return addressof_var(name)
+            make_accessor(name)
+            if name in library.__dict__:
+                return library.__dict__[name]
+            if name in FFILibrary.__dict__:
+                return addressof_var(name)
+            raise AttributeError("cffi library has no function or "
+                                 "global variable named '%s'" % (name,))
+        def __cffi_close__(self):
+            backendlib.close_lib()
+            self.__dict__.clear()
+    #
+    if isinstance(libname, basestring):
+        try:
+            if not isinstance(libname, str):    # unicode, on Python 2
+                libname = libname.encode('utf-8')
+            FFILibrary.__name__ = 'FFILibrary_%s' % libname
+        except UnicodeError:
+            pass
+    library = FFILibrary()
+    return library, library.__dict__
+
+def _builtin_function_type(func):
+    # a hack to make at least ffi.typeof(builtin_function) work,
+    # if the builtin function was obtained by 'vengine_cpy'.
+    import sys
+    try:
+        module = sys.modules[func.__module__]
+        ffi = module._cffi_original_ffi
+        types_of_builtin_funcs = module._cffi_types_of_builtin_funcs
+        tp = types_of_builtin_funcs[func]
+    except (KeyError, AttributeError, TypeError):
+        return None
+    else:
+        with ffi._lock:
+            return ffi._get_cached_btype(tp)

venv/Lib/site-packages/cffi/cffi_opcode.py

@@ -0,0 +1,187 @@
+from .error import VerificationError
+
+class CffiOp(object):
+    def __init__(self, op, arg):
+        self.op = op
+        self.arg = arg
+
+    def as_c_expr(self):
+        if self.op is None:
+            assert isinstance(self.arg, str)
+            return '(_cffi_opcode_t)(%s)' % (self.arg,)
+        classname = CLASS_NAME[self.op]
+        return '_CFFI_OP(_CFFI_OP_%s, %s)' % (classname, self.arg)
+
+    def as_python_bytes(self):
+        if self.op is None and self.arg.isdigit():
+            value = int(self.arg)     # non-negative: '-' not in self.arg
+            if value >= 2**31:
+                raise OverflowError("cannot emit %r: limited to 2**31-1"
+                                    % (self.arg,))
+            return format_four_bytes(value)
+        if isinstance(self.arg, str):
+            raise VerificationError("cannot emit to Python: %r" % (self.arg,))
+        return format_four_bytes((self.arg << 8) | self.op)
+
+    def __str__(self):
+        classname = CLASS_NAME.get(self.op, self.op)
+        return '(%s %s)' % (classname, self.arg)
+
+def format_four_bytes(num):
+    return '\\x%02X\\x%02X\\x%02X\\x%02X' % (
+        (num >> 24) & 0xFF,
+        (num >> 16) & 0xFF,
+        (num >>  8) & 0xFF,
+        (num      ) & 0xFF)
+
+OP_PRIMITIVE       = 1
+OP_POINTER         = 3
+OP_ARRAY           = 5
+OP_OPEN_ARRAY      = 7
+OP_STRUCT_UNION    = 9
+OP_ENUM            = 11
+OP_FUNCTION        = 13
+OP_FUNCTION_END    = 15
+OP_NOOP            = 17
+OP_BITFIELD        = 19
+OP_TYPENAME        = 21
+OP_CPYTHON_BLTN_V  = 23   # varargs
+OP_CPYTHON_BLTN_N  = 25   # noargs
+OP_CPYTHON_BLTN_O  = 27   # O  (i.e. a single arg)
+OP_CONSTANT        = 29
+OP_CONSTANT_INT    = 31
+OP_GLOBAL_VAR      = 33
+OP_DLOPEN_FUNC     = 35
+OP_DLOPEN_CONST    = 37
+OP_GLOBAL_VAR_F    = 39
+OP_EXTERN_PYTHON   = 41
+
+PRIM_VOID          = 0
+PRIM_BOOL          = 1
+PRIM_CHAR          = 2
+PRIM_SCHAR         = 3
+PRIM_UCHAR         = 4
+PRIM_SHORT         = 5
+PRIM_USHORT        = 6
+PRIM_INT           = 7
+PRIM_UINT          = 8
+PRIM_LONG          = 9
+PRIM_ULONG         = 10
+PRIM_LONGLONG      = 11
+PRIM_ULONGLONG     = 12
+PRIM_FLOAT         = 13
+PRIM_DOUBLE        = 14
+PRIM_LONGDOUBLE    = 15
+
+PRIM_WCHAR         = 16
+PRIM_INT8          = 17
+PRIM_UINT8         = 18
+PRIM_INT16         = 19
+PRIM_UINT16        = 20
+PRIM_INT32         = 21
+PRIM_UINT32        = 22
+PRIM_INT64         = 23
+PRIM_UINT64        = 24
+PRIM_INTPTR        = 25
+PRIM_UINTPTR       = 26
+PRIM_PTRDIFF       = 27
+PRIM_SIZE          = 28
+PRIM_SSIZE         = 29
+PRIM_INT_LEAST8    = 30
+PRIM_UINT_LEAST8   = 31
+PRIM_INT_LEAST16   = 32
+PRIM_UINT_LEAST16  = 33
+PRIM_INT_LEAST32   = 34
+PRIM_UINT_LEAST32  = 35
+PRIM_INT_LEAST64   = 36
+PRIM_UINT_LEAST64  = 37
+PRIM_INT_FAST8     = 38
+PRIM_UINT_FAST8    = 39
+PRIM_INT_FAST16    = 40
+PRIM_UINT_FAST16   = 41
+PRIM_INT_FAST32    = 42
+PRIM_UINT_FAST32   = 43
+PRIM_INT_FAST64    = 44
+PRIM_UINT_FAST64   = 45
+PRIM_INTMAX        = 46
+PRIM_UINTMAX       = 47
+PRIM_FLOATCOMPLEX  = 48
+PRIM_DOUBLECOMPLEX = 49
+PRIM_CHAR16        = 50
+PRIM_CHAR32        = 51
+
+_NUM_PRIM          = 52
+_UNKNOWN_PRIM          = -1
+_UNKNOWN_FLOAT_PRIM    = -2
+_UNKNOWN_LONG_DOUBLE   = -3
+
+_IO_FILE_STRUCT        = -1
+
+PRIMITIVE_TO_INDEX = {
+    'char':               PRIM_CHAR,
+    'short':              PRIM_SHORT,
+    'int':                PRIM_INT,
+    'long':               PRIM_LONG,
+    'long long':          PRIM_LONGLONG,
+    'signed char':        PRIM_SCHAR,
+    'unsigned char':      PRIM_UCHAR,
+    'unsigned short':     PRIM_USHORT,
+    'unsigned int':       PRIM_UINT,
+    'unsigned long':      PRIM_ULONG,
+    'unsigned long long': PRIM_ULONGLONG,
+    'float':              PRIM_FLOAT,
+    'double':             PRIM_DOUBLE,
+    'long double':        PRIM_LONGDOUBLE,
+    'float _Complex':     PRIM_FLOATCOMPLEX,
+    'double _Complex':    PRIM_DOUBLECOMPLEX,
+    '_Bool':              PRIM_BOOL,
+    'wchar_t':            PRIM_WCHAR,
+    'char16_t':           PRIM_CHAR16,
+    'char32_t':           PRIM_CHAR32,
+    'int8_t':             PRIM_INT8,
+    'uint8_t':            PRIM_UINT8,
+    'int16_t':            PRIM_INT16,
+    'uint16_t':           PRIM_UINT16,
+    'int32_t':            PRIM_INT32,
+    'uint32_t':           PRIM_UINT32,
+    'int64_t':            PRIM_INT64,
+    'uint64_t':           PRIM_UINT64,
+    'intptr_t':           PRIM_INTPTR,
+    'uintptr_t':          PRIM_UINTPTR,
+    'ptrdiff_t':          PRIM_PTRDIFF,
+    'size_t':             PRIM_SIZE,
+    'ssize_t':            PRIM_SSIZE,
+    'int_least8_t':       PRIM_INT_LEAST8,
+    'uint_least8_t':      PRIM_UINT_LEAST8,
+    'int_least16_t':      PRIM_INT_LEAST16,
+    'uint_least16_t':     PRIM_UINT_LEAST16,
+    'int_least32_t':      PRIM_INT_LEAST32,
+    'uint_least32_t':     PRIM_UINT_LEAST32,
+    'int_least64_t':      PRIM_INT_LEAST64,
+    'uint_least64_t':     PRIM_UINT_LEAST64,
+    'int_fast8_t':        PRIM_INT_FAST8,
+    'uint_fast8_t':       PRIM_UINT_FAST8,
+    'int_fast16_t':       PRIM_INT_FAST16,
+    'uint_fast16_t':      PRIM_UINT_FAST16,
+    'int_fast32_t':       PRIM_INT_FAST32,
+    'uint_fast32_t':      PRIM_UINT_FAST32,
+    'int_fast64_t':       PRIM_INT_FAST64,
+    'uint_fast64_t':      PRIM_UINT_FAST64,
+    'intmax_t':           PRIM_INTMAX,
+    'uintmax_t':          PRIM_UINTMAX,
+    }
+
+F_UNION         = 0x01
+F_CHECK_FIELDS  = 0x02
+F_PACKED        = 0x04
+F_EXTERNAL      = 0x08
+F_OPAQUE        = 0x10
+
+G_FLAGS = dict([('_CFFI_' + _key, globals()[_key])
+                for _key in ['F_UNION', 'F_CHECK_FIELDS', 'F_PACKED',
+                             'F_EXTERNAL', 'F_OPAQUE']])
+
+CLASS_NAME = {}
+for _name, _value in list(globals().items()):
+    if _name.startswith('OP_') and isinstance(_value, int):
+        CLASS_NAME[_value] = _name[3:]

venv/Lib/site-packages/cffi/commontypes.py

@@ -0,0 +1,80 @@
+import sys
+from . import model
+from .error import FFIError
+
+
+COMMON_TYPES = {}
+
+try:
+    # fetch "bool" and all simple Windows types
+    from _cffi_backend import _get_common_types
+    _get_common_types(COMMON_TYPES)
+except ImportError:
+    pass
+
+COMMON_TYPES['FILE'] = model.unknown_type('FILE', '_IO_FILE')
+COMMON_TYPES['bool'] = '_Bool'    # in case we got ImportError above
+
+for _type in model.PrimitiveType.ALL_PRIMITIVE_TYPES:
+    if _type.endswith('_t'):
+        COMMON_TYPES[_type] = _type
+del _type
+
+_CACHE = {}
+
+def resolve_common_type(parser, commontype):
+    try:
+        return _CACHE[commontype]
+    except KeyError:
+        cdecl = COMMON_TYPES.get(commontype, commontype)
+        if not isinstance(cdecl, str):
+            result, quals = cdecl, 0    # cdecl is already a BaseType
+        elif cdecl in model.PrimitiveType.ALL_PRIMITIVE_TYPES:
+            result, quals = model.PrimitiveType(cdecl), 0
+        elif cdecl == 'set-unicode-needed':
+            raise FFIError("The Windows type %r is only available after "
+                           "you call ffi.set_unicode()" % (commontype,))
+        else:
+            if commontype == cdecl:
+                raise FFIError(
+                    "Unsupported type: %r.  Please look at "
+        "http://cffi.readthedocs.io/en/latest/cdef.html#ffi-cdef-limitations "
+                    "and file an issue if you think this type should really "
+                    "be supported." % (commontype,))
+            result, quals = parser.parse_type_and_quals(cdecl)   # recursive
+
+        assert isinstance(result, model.BaseTypeByIdentity)
+        _CACHE[commontype] = result, quals
+        return result, quals
+
+
+# ____________________________________________________________
+# extra types for Windows (most of them are in commontypes.c)
+
+
+def win_common_types():
+    return {
+        "UNICODE_STRING": model.StructType(
+            "_UNICODE_STRING",
+            ["Length",
+             "MaximumLength",
+             "Buffer"],
+            [model.PrimitiveType("unsigned short"),
+             model.PrimitiveType("unsigned short"),
+             model.PointerType(model.PrimitiveType("wchar_t"))],
+            [-1, -1, -1]),
+        "PUNICODE_STRING": "UNICODE_STRING *",
+        "PCUNICODE_STRING": "const UNICODE_STRING *",
+
+        "TBYTE": "set-unicode-needed",
+        "TCHAR": "set-unicode-needed",
+        "LPCTSTR": "set-unicode-needed",
+        "PCTSTR": "set-unicode-needed",
+        "LPTSTR": "set-unicode-needed",
+        "PTSTR": "set-unicode-needed",
+        "PTBYTE": "set-unicode-needed",
+        "PTCHAR": "set-unicode-needed",
+        }
+
+if sys.platform == 'win32':
+    COMMON_TYPES.update(win_common_types())

venv/Lib/site-packages/cffi/error.py

@@ -0,0 +1,31 @@
+
+class FFIError(Exception):
+    __module__ = 'cffi'
+
+class CDefError(Exception):
+    __module__ = 'cffi'
+    def __str__(self):
+        try:
+            current_decl = self.args[1]
+            filename = current_decl.coord.file
+            linenum = current_decl.coord.line
+            prefix = '%s:%d: ' % (filename, linenum)
+        except (AttributeError, TypeError, IndexError):
+            prefix = ''
+        return '%s%s' % (prefix, self.args[0])
+
+class VerificationError(Exception):
+    """ An error raised when verification fails
+    """
+    __module__ = 'cffi'
+
+class VerificationMissing(Exception):
+    """ An error raised when incomplete structures are passed into
+    cdef, but no verification has been done
+    """
+    __module__ = 'cffi'
+
+class PkgConfigError(Exception):
+    """ An error raised for missing modules in pkg-config
+    """
+    __module__ = 'cffi'

venv/Lib/site-packages/cffi/ffiplatform.py

@@ -0,0 +1,127 @@
+import sys, os
+from .error import VerificationError
+
+
+LIST_OF_FILE_NAMES = ['sources', 'include_dirs', 'library_dirs',
+                      'extra_objects', 'depends']
+
+def get_extension(srcfilename, modname, sources=(), **kwds):
+    _hack_at_distutils()
+    from distutils.core import Extension
+    allsources = [srcfilename]
+    for src in sources:
+        allsources.append(os.path.normpath(src))
+    return Extension(name=modname, sources=allsources, **kwds)
+
+def compile(tmpdir, ext, compiler_verbose=0, debug=None):
+    """Compile a C extension module using distutils."""
+
+    _hack_at_distutils()
+    saved_environ = os.environ.copy()
+    try:
+        outputfilename = _build(tmpdir, ext, compiler_verbose, debug)
+        outputfilename = os.path.abspath(outputfilename)
+    finally:
+        # workaround for a distutils bugs where some env vars can
+        # become longer and longer every time it is used
+        for key, value in saved_environ.items():
+            if os.environ.get(key) != value:
+                os.environ[key] = value
+    return outputfilename
+
+def _build(tmpdir, ext, compiler_verbose=0, debug=None):
+    # XXX compact but horrible :-(
+    from distutils.core import Distribution
+    import distutils.errors, distutils.log
+    #
+    dist = Distribution({'ext_modules': [ext]})
+    dist.parse_config_files()
+    options = dist.get_option_dict('build_ext')
+    if debug is None:
+        debug = sys.flags.debug
+    options['debug'] = ('ffiplatform', debug)
+    options['force'] = ('ffiplatform', True)
+    options['build_lib'] = ('ffiplatform', tmpdir)
+    options['build_temp'] = ('ffiplatform', tmpdir)
+    #
+    try:
+        old_level = distutils.log.set_threshold(0) or 0
+        try:
+            distutils.log.set_verbosity(compiler_verbose)
+            dist.run_command('build_ext')
+            cmd_obj = dist.get_command_obj('build_ext')
+            [soname] = cmd_obj.get_outputs()
+        finally:
+            distutils.log.set_threshold(old_level)
+    except (distutils.errors.CompileError,
+            distutils.errors.LinkError) as e:
+        raise VerificationError('%s: %s' % (e.__class__.__name__, e))
+    #
+    return soname
+
+try:
+    from os.path import samefile
+except ImportError:
+    def samefile(f1, f2):
+        return os.path.abspath(f1) == os.path.abspath(f2)
+
+def maybe_relative_path(path):
+    if not os.path.isabs(path):
+        return path      # already relative
+    dir = path
+    names = []
+    while True:
+        prevdir = dir
+        dir, name = os.path.split(prevdir)
+        if dir == prevdir or not dir:
+            return path     # failed to make it relative
+        names.append(name)
+        try:
+            if samefile(dir, os.curdir):
+                names.reverse()
+                return os.path.join(*names)
+        except OSError:
+            pass
+
+# ____________________________________________________________
+
+try:
+    int_or_long = (int, long)
+    import cStringIO
+except NameError:
+    int_or_long = int      # Python 3
+    import io as cStringIO
+
+def _flatten(x, f):
+    if isinstance(x, str):
+        f.write('%ds%s' % (len(x), x))
+    elif isinstance(x, dict):
+        keys = sorted(x.keys())
+        f.write('%dd' % len(keys))
+        for key in keys:
+            _flatten(key, f)
+            _flatten(x[key], f)
+    elif isinstance(x, (list, tuple)):
+        f.write('%dl' % len(x))
+        for value in x:
+            _flatten(value, f)
+    elif isinstance(x, int_or_long):
+        f.write('%di' % (x,))
+    else:
+        raise TypeError(
+            "the keywords to verify() contains unsupported object %r" % (x,))
+
+def flatten(x):
+    f = cStringIO.StringIO()
+    _flatten(x, f)
+    return f.getvalue()
+
+def _hack_at_distutils():
+    # Windows-only workaround for some configurations: see
+    # https://bugs.python.org/issue23246 (Python 2.7 with 
+    # a specific MS compiler suite download)
+    if sys.platform == "win32":
+        try:
+            import setuptools    # for side-effects, patches distutils
+        except ImportError:
+            pass

venv/Lib/site-packages/cffi/lock.py

@@ -0,0 +1,30 @@
+import sys
+
+if sys.version_info < (3,):
+    try:
+        from thread import allocate_lock
+    except ImportError:
+        from dummy_thread import allocate_lock
+else:
+    try:
+        from _thread import allocate_lock
+    except ImportError:
+        from _dummy_thread import allocate_lock
+
+
+##import sys
+##l1 = allocate_lock
+
+##class allocate_lock(object):
+##    def __init__(self):
+##        self._real = l1()
+##    def __enter__(self):
+##        for i in range(4, 0, -1):
+##            print sys._getframe(i).f_code
+##        print
+##        return self._real.__enter__()
+##    def __exit__(self, *args):
+##        return self._real.__exit__(*args)
+##    def acquire(self, f):
+##        assert f is False
+##        return self._real.acquire(f)

venv/Lib/site-packages/cffi/model.py

@@ -0,0 +1,617 @@
+import types
+import weakref
+
+from .lock import allocate_lock
+from .error import CDefError, VerificationError, VerificationMissing
+
+# type qualifiers
+Q_CONST    = 0x01
+Q_RESTRICT = 0x02
+Q_VOLATILE = 0x04
+
+def qualify(quals, replace_with):
+    if quals & Q_CONST:
+        replace_with = ' const ' + replace_with.lstrip()
+    if quals & Q_VOLATILE:
+        replace_with = ' volatile ' + replace_with.lstrip()
+    if quals & Q_RESTRICT:
+        # It seems that __restrict is supported by gcc and msvc.
+        # If you hit some different compiler, add a #define in
+        # _cffi_include.h for it (and in its copies, documented there)
+        replace_with = ' __restrict ' + replace_with.lstrip()
+    return replace_with
+
+
+class BaseTypeByIdentity(object):
+    is_array_type = False
+    is_raw_function = False
+
+    def get_c_name(self, replace_with='', context='a C file', quals=0):
+        result = self.c_name_with_marker
+        assert result.count('&') == 1
+        # some logic duplication with ffi.getctype()... :-(
+        replace_with = replace_with.strip()
+        if replace_with:
+            if replace_with.startswith('*') and '&[' in result:
+                replace_with = '(%s)' % replace_with
+            elif not replace_with[0] in '[(':
+                replace_with = ' ' + replace_with
+        replace_with = qualify(quals, replace_with)
+        result = result.replace('&', replace_with)
+        if '$' in result:
+            raise VerificationError(
+                "cannot generate '%s' in %s: unknown type name"
+                % (self._get_c_name(), context))
+        return result
+
+    def _get_c_name(self):
+        return self.c_name_with_marker.replace('&', '')
+
+    def has_c_name(self):
+        return '$' not in self._get_c_name()
+
+    def is_integer_type(self):
+        return False
+
+    def get_cached_btype(self, ffi, finishlist, can_delay=False):
+        try:
+            BType = ffi._cached_btypes[self]
+        except KeyError:
+            BType = self.build_backend_type(ffi, finishlist)
+            BType2 = ffi._cached_btypes.setdefault(self, BType)
+            assert BType2 is BType
+        return BType
+
+    def __repr__(self):
+        return '<%s>' % (self._get_c_name(),)
+
+    def _get_items(self):
+        return [(name, getattr(self, name)) for name in self._attrs_]
+
+
+class BaseType(BaseTypeByIdentity):
+
+    def __eq__(self, other):
+        return (self.__class__ == other.__class__ and
+                self._get_items() == other._get_items())
+
+    def __ne__(self, other):
+        return not self == other
+
+    def __hash__(self):
+        return hash((self.__class__, tuple(self._get_items())))
+
+
+class VoidType(BaseType):
+    _attrs_ = ()
+
+    def __init__(self):
+        self.c_name_with_marker = 'void&'
+
+    def build_backend_type(self, ffi, finishlist):
+        return global_cache(self, ffi, 'new_void_type')
+
+void_type = VoidType()
+
+
+class BasePrimitiveType(BaseType):
+    def is_complex_type(self):
+        return False
+
+
+class PrimitiveType(BasePrimitiveType):
+    _attrs_ = ('name',)
+
+    ALL_PRIMITIVE_TYPES = {
+        'char':               'c',
+        'short':              'i',
+        'int':                'i',
+        'long':               'i',
+        'long long':          'i',
+        'signed char':        'i',
+        'unsigned char':      'i',
+        'unsigned short':     'i',
+        'unsigned int':       'i',
+        'unsigned long':      'i',
+        'unsigned long long': 'i',
+        'float':              'f',
+        'double':             'f',
+        'long double':        'f',
+        'float _Complex':     'j',
+        'double _Complex':    'j',
+        '_Bool':              'i',
+        # the following types are not primitive in the C sense
+        'wchar_t':            'c',
+        'char16_t':           'c',
+        'char32_t':           'c',
+        'int8_t':             'i',
+        'uint8_t':            'i',
+        'int16_t':            'i',
+        'uint16_t':           'i',
+        'int32_t':            'i',
+        'uint32_t':           'i',
+        'int64_t':            'i',
+        'uint64_t':           'i',
+        'int_least8_t':       'i',
+        'uint_least8_t':      'i',
+        'int_least16_t':      'i',
+        'uint_least16_t':     'i',
+        'int_least32_t':      'i',
+        'uint_least32_t':     'i',
+        'int_least64_t':      'i',
+        'uint_least64_t':     'i',
+        'int_fast8_t':        'i',
+        'uint_fast8_t':       'i',
+        'int_fast16_t':       'i',
+        'uint_fast16_t':      'i',
+        'int_fast32_t':       'i',
+        'uint_fast32_t':      'i',
+        'int_fast64_t':       'i',
+        'uint_fast64_t':      'i',
+        'intptr_t':           'i',
+        'uintptr_t':          'i',
+        'intmax_t':           'i',
+        'uintmax_t':          'i',
+        'ptrdiff_t':          'i',
+        'size_t':             'i',
+        'ssize_t':            'i',
+        }
+
+    def __init__(self, name):
+        assert name in self.ALL_PRIMITIVE_TYPES
+        self.name = name
+        self.c_name_with_marker = name + '&'
+
+    def is_char_type(self):
+        return self.ALL_PRIMITIVE_TYPES[self.name] == 'c'
+    def is_integer_type(self):
+        return self.ALL_PRIMITIVE_TYPES[self.name] == 'i'
+    def is_float_type(self):
+        return self.ALL_PRIMITIVE_TYPES[self.name] == 'f'
+    def is_complex_type(self):
+        return self.ALL_PRIMITIVE_TYPES[self.name] == 'j'
+
+    def build_backend_type(self, ffi, finishlist):
+        return global_cache(self, ffi, 'new_primitive_type', self.name)
+
+
+class UnknownIntegerType(BasePrimitiveType):
+    _attrs_ = ('name',)
+
+    def __init__(self, name):
+        self.name = name
+        self.c_name_with_marker = name + '&'
+
+    def is_integer_type(self):
+        return True
+
+    def build_backend_type(self, ffi, finishlist):
+        raise NotImplementedError("integer type '%s' can only be used after "
+                                  "compilation" % self.name)
+
+class UnknownFloatType(BasePrimitiveType):
+    _attrs_ = ('name', )
+
+    def __init__(self, name):
+        self.name = name
+        self.c_name_with_marker = name + '&'
+
+    def build_backend_type(self, ffi, finishlist):
+        raise NotImplementedError("float type '%s' can only be used after "
+                                  "compilation" % self.name)
+
+
+class BaseFunctionType(BaseType):
+    _attrs_ = ('args', 'result', 'ellipsis', 'abi')
+
+    def __init__(self, args, result, ellipsis, abi=None):
+        self.args = args
+        self.result = result
+        self.ellipsis = ellipsis
+        self.abi = abi
+        #
+        reprargs = [arg._get_c_name() for arg in self.args]
+        if self.ellipsis:
+            reprargs.append('...')
+        reprargs = reprargs or ['void']
+        replace_with = self._base_pattern % (', '.join(reprargs),)
+        if abi is not None:
+            replace_with = replace_with[:1] + abi + ' ' + replace_with[1:]
+        self.c_name_with_marker = (
+            self.result.c_name_with_marker.replace('&', replace_with))
+
+
+class RawFunctionType(BaseFunctionType):
+    # Corresponds to a C type like 'int(int)', which is the C type of
+    # a function, but not a pointer-to-function.  The backend has no
+    # notion of such a type; it's used temporarily by parsing.
+    _base_pattern = '(&)(%s)'
+    is_raw_function = True
+
+    def build_backend_type(self, ffi, finishlist):
+        raise CDefError("cannot render the type %r: it is a function "
+                        "type, not a pointer-to-function type" % (self,))
+
+    def as_function_pointer(self):
+        return FunctionPtrType(self.args, self.result, self.ellipsis, self.abi)
+
+
+class FunctionPtrType(BaseFunctionType):
+    _base_pattern = '(*&)(%s)'
+
+    def build_backend_type(self, ffi, finishlist):
+        result = self.result.get_cached_btype(ffi, finishlist)
+        args = []
+        for tp in self.args:
+            args.append(tp.get_cached_btype(ffi, finishlist))
+        abi_args = ()
+        if self.abi == "__stdcall":
+            if not self.ellipsis:    # __stdcall ignored for variadic funcs
+                try:
+                    abi_args = (ffi._backend.FFI_STDCALL,)
+                except AttributeError:
+                    pass
+        return global_cache(self, ffi, 'new_function_type',
+                            tuple(args), result, self.ellipsis, *abi_args)
+
+    def as_raw_function(self):
+        return RawFunctionType(self.args, self.result, self.ellipsis, self.abi)
+
+
+class PointerType(BaseType):
+    _attrs_ = ('totype', 'quals')
+
+    def __init__(self, totype, quals=0):
+        self.totype = totype
+        self.quals = quals
+        extra = qualify(quals, " *&")
+        if totype.is_array_type:
+            extra = "(%s)" % (extra.lstrip(),)
+        self.c_name_with_marker = totype.c_name_with_marker.replace('&', extra)
+
+    def build_backend_type(self, ffi, finishlist):
+        BItem = self.totype.get_cached_btype(ffi, finishlist, can_delay=True)
+        return global_cache(self, ffi, 'new_pointer_type', BItem)
+
+voidp_type = PointerType(void_type)
+
+def ConstPointerType(totype):
+    return PointerType(totype, Q_CONST)
+
+const_voidp_type = ConstPointerType(void_type)
+
+
+class NamedPointerType(PointerType):
+    _attrs_ = ('totype', 'name')
+
+    def __init__(self, totype, name, quals=0):
+        PointerType.__init__(self, totype, quals)
+        self.name = name
+        self.c_name_with_marker = name + '&'
+
+
+class ArrayType(BaseType):
+    _attrs_ = ('item', 'length')
+    is_array_type = True
+
+    def __init__(self, item, length):
+        self.item = item
+        self.length = length
+        #
+        if length is None:
+            brackets = '&[]'
+        elif length == '...':
+            brackets = '&[/*...*/]'
+        else:
+            brackets = '&[%s]' % length
+        self.c_name_with_marker = (
+            self.item.c_name_with_marker.replace('&', brackets))
+
+    def length_is_unknown(self):
+        return isinstance(self.length, str)
+
+    def resolve_length(self, newlength):
+        return ArrayType(self.item, newlength)
+
+    def build_backend_type(self, ffi, finishlist):
+        if self.length_is_unknown():
+            raise CDefError("cannot render the type %r: unknown length" %
+                            (self,))
+        self.item.get_cached_btype(ffi, finishlist)   # force the item BType
+        BPtrItem = PointerType(self.item).get_cached_btype(ffi, finishlist)
+        return global_cache(self, ffi, 'new_array_type', BPtrItem, self.length)
+
+char_array_type = ArrayType(PrimitiveType('char'), None)
+
+
+class StructOrUnionOrEnum(BaseTypeByIdentity):
+    _attrs_ = ('name',)
+    forcename = None
+
+    def build_c_name_with_marker(self):
+        name = self.forcename or '%s %s' % (self.kind, self.name)
+        self.c_name_with_marker = name + '&'
+
+    def force_the_name(self, forcename):
+        self.forcename = forcename
+        self.build_c_name_with_marker()
+
+    def get_official_name(self):
+        assert self.c_name_with_marker.endswith('&')
+        return self.c_name_with_marker[:-1]
+
+
+class StructOrUnion(StructOrUnionOrEnum):
+    fixedlayout = None
+    completed = 0
+    partial = False
+    packed = 0
+
+    def __init__(self, name, fldnames, fldtypes, fldbitsize, fldquals=None):
+        self.name = name
+        self.fldnames = fldnames
+        self.fldtypes = fldtypes
+        self.fldbitsize = fldbitsize
+        self.fldquals = fldquals
+        self.build_c_name_with_marker()
+
+    def anonymous_struct_fields(self):
+        if self.fldtypes is not None:
+            for name, type in zip(self.fldnames, self.fldtypes):
+                if name == '' and isinstance(type, StructOrUnion):
+                    yield type
+
+    def enumfields(self, expand_anonymous_struct_union=True):
+        fldquals = self.fldquals
+        if fldquals is None:
+            fldquals = (0,) * len(self.fldnames)
+        for name, type, bitsize, quals in zip(self.fldnames, self.fldtypes,
+                                              self.fldbitsize, fldquals):
+            if (name == '' and isinstance(type, StructOrUnion)
+                    and expand_anonymous_struct_union):
+                # nested anonymous struct/union
+                for result in type.enumfields():
+                    yield result
+            else:
+                yield (name, type, bitsize, quals)
+
+    def force_flatten(self):
+        # force the struct or union to have a declaration that lists
+        # directly all fields returned by enumfields(), flattening
+        # nested anonymous structs/unions.
+        names = []
+        types = []
+        bitsizes = []
+        fldquals = []
+        for name, type, bitsize, quals in self.enumfields():
+            names.append(name)
+            types.append(type)
+            bitsizes.append(bitsize)
+            fldquals.append(quals)
+        self.fldnames = tuple(names)
+        self.fldtypes = tuple(types)
+        self.fldbitsize = tuple(bitsizes)
+        self.fldquals = tuple(fldquals)
+
+    def get_cached_btype(self, ffi, finishlist, can_delay=False):
+        BType = StructOrUnionOrEnum.get_cached_btype(self, ffi, finishlist,
+                                                     can_delay)
+        if not can_delay:
+            self.finish_backend_type(ffi, finishlist)
+        return BType
+
+    def finish_backend_type(self, ffi, finishlist):
+        if self.completed:
+            if self.completed != 2:
+                raise NotImplementedError("recursive structure declaration "
+                                          "for '%s'" % (self.name,))
+            return
+        BType = ffi._cached_btypes[self]
+        #
+        self.completed = 1
+        #
+        if self.fldtypes is None:
+            pass    # not completing it: it's an opaque struct
+            #
+        elif self.fixedlayout is None:
+            fldtypes = [tp.get_cached_btype(ffi, finishlist)
+                        for tp in self.fldtypes]
+            lst = list(zip(self.fldnames, fldtypes, self.fldbitsize))
+            extra_flags = ()
+            if self.packed:
+                if self.packed == 1:
+                    extra_flags = (8,)    # SF_PACKED
+                else:
+                    extra_flags = (0, self.packed)
+            ffi._backend.complete_struct_or_union(BType, lst, self,
+                                                  -1, -1, *extra_flags)
+            #
+        else:
+            fldtypes = []
+            fieldofs, fieldsize, totalsize, totalalignment = self.fixedlayout
+            for i in range(len(self.fldnames)):
+                fsize = fieldsize[i]
+                ftype = self.fldtypes[i]
+                #
+                if isinstance(ftype, ArrayType) and ftype.length_is_unknown():
+                    # fix the length to match the total size
+                    BItemType = ftype.item.get_cached_btype(ffi, finishlist)
+                    nlen, nrest = divmod(fsize, ffi.sizeof(BItemType))
+                    if nrest != 0:
+                        self._verification_error(
+                            "field '%s.%s' has a bogus size?" % (
+                            self.name, self.fldnames[i] or '{}'))
+                    ftype = ftype.resolve_length(nlen)
+                    self.fldtypes = (self.fldtypes[:i] + (ftype,) +
+                                     self.fldtypes[i+1:])
+                #
+                BFieldType = ftype.get_cached_btype(ffi, finishlist)
+                if isinstance(ftype, ArrayType) and ftype.length is None:
+                    assert fsize == 0
+                else:
+                    bitemsize = ffi.sizeof(BFieldType)
+                    if bitemsize != fsize:
+                        self._verification_error(
+                            "field '%s.%s' is declared as %d bytes, but is "
+                            "really %d bytes" % (self.name,
+                                                 self.fldnames[i] or '{}',
+                                                 bitemsize, fsize))
+                fldtypes.append(BFieldType)
+            #
+            lst = list(zip(self.fldnames, fldtypes, self.fldbitsize, fieldofs))
+            ffi._backend.complete_struct_or_union(BType, lst, self,
+                                                  totalsize, totalalignment)
+        self.completed = 2
+
+    def _verification_error(self, msg):
+        raise VerificationError(msg)
+
+    def check_not_partial(self):
+        if self.partial and self.fixedlayout is None:
+            raise VerificationMissing(self._get_c_name())
+
+    def build_backend_type(self, ffi, finishlist):
+        self.check_not_partial()
+        finishlist.append(self)
+        #
+        return global_cache(self, ffi, 'new_%s_type' % self.kind,
+                            self.get_official_name(), key=self)
+
+
+class StructType(StructOrUnion):
+    kind = 'struct'
+
+
+class UnionType(StructOrUnion):
+    kind = 'union'
+
+
+class EnumType(StructOrUnionOrEnum):
+    kind = 'enum'
+    partial = False
+    partial_resolved = False
+
+    def __init__(self, name, enumerators, enumvalues, baseinttype=None):
+        self.name = name
+        self.enumerators = enumerators
+        self.enumvalues = enumvalues
+        self.baseinttype = baseinttype
+        self.build_c_name_with_marker()
+
+    def force_the_name(self, forcename):
+        StructOrUnionOrEnum.force_the_name(self, forcename)
+        if self.forcename is None:
+            name = self.get_official_name()
+            self.forcename = '$' + name.replace(' ', '_')
+
+    def check_not_partial(self):
+        if self.partial and not self.partial_resolved:
+            raise VerificationMissing(self._get_c_name())
+
+    def build_backend_type(self, ffi, finishlist):
+        self.check_not_partial()
+        base_btype = self.build_baseinttype(ffi, finishlist)
+        return global_cache(self, ffi, 'new_enum_type',
+                            self.get_official_name(),
+                            self.enumerators, self.enumvalues,
+                            base_btype, key=self)
+
+    def build_baseinttype(self, ffi, finishlist):
+        if self.baseinttype is not None:
+            return self.baseinttype.get_cached_btype(ffi, finishlist)
+        #
+        if self.enumvalues:
+            smallest_value = min(self.enumvalues)
+            largest_value = max(self.enumvalues)
+        else:
+            import warnings
+            try:
+                # XXX!  The goal is to ensure that the warnings.warn()
+                # will not suppress the warning.  We want to get it
+                # several times if we reach this point several times.
+                __warningregistry__.clear()
+            except NameError:
+                pass
+            warnings.warn("%r has no values explicitly defined; "
+                          "guessing that it is equivalent to 'unsigned int'"
+                          % self._get_c_name())
+            smallest_value = largest_value = 0
+        if smallest_value < 0:   # needs a signed type
+            sign = 1
+            candidate1 = PrimitiveType("int")
+            candidate2 = PrimitiveType("long")
+        else:
+            sign = 0
+            candidate1 = PrimitiveType("unsigned int")
+            candidate2 = PrimitiveType("unsigned long")
+        btype1 = candidate1.get_cached_btype(ffi, finishlist)
+        btype2 = candidate2.get_cached_btype(ffi, finishlist)
+        size1 = ffi.sizeof(btype1)
+        size2 = ffi.sizeof(btype2)
+        if (smallest_value >= ((-1) << (8*size1-1)) and
+            largest_value < (1 << (8*size1-sign))):
+            return btype1
+        if (smallest_value >= ((-1) << (8*size2-1)) and
+            largest_value < (1 << (8*size2-sign))):
+            return btype2
+        raise CDefError("%s values don't all fit into either 'long' "
+                        "or 'unsigned long'" % self._get_c_name())
+
+def unknown_type(name, structname=None):
+    if structname is None:
+        structname = '$%s' % name
+    tp = StructType(structname, None, None, None)
+    tp.force_the_name(name)
+    tp.origin = "unknown_type"
+    return tp
+
+def unknown_ptr_type(name, structname=None):
+    if structname is None:
+        structname = '$$%s' % name
+    tp = StructType(structname, None, None, None)
+    return NamedPointerType(tp, name)
+
+
+global_lock = allocate_lock()
+_typecache_cffi_backend = weakref.WeakValueDictionary()
+
+def get_typecache(backend):
+    # returns _typecache_cffi_backend if backend is the _cffi_backend
+    # module, or type(backend).__typecache if backend is an instance of
+    # CTypesBackend (or some FakeBackend class during tests)
+    if isinstance(backend, types.ModuleType):
+        return _typecache_cffi_backend
+    with global_lock:
+        if not hasattr(type(backend), '__typecache'):
+            type(backend).__typecache = weakref.WeakValueDictionary()
+        return type(backend).__typecache
+
+def global_cache(srctype, ffi, funcname, *args, **kwds):
+    key = kwds.pop('key', (funcname, args))
+    assert not kwds
+    try:
+        return ffi._typecache[key]
+    except KeyError:
+        pass
+    try:
+        res = getattr(ffi._backend, funcname)(*args)
+    except NotImplementedError as e:
+        raise NotImplementedError("%s: %r: %s" % (funcname, srctype, e))
+    # note that setdefault() on WeakValueDictionary is not atomic
+    # and contains a rare bug (http://bugs.python.org/issue19542);
+    # we have to use a lock and do it ourselves
+    cache = ffi._typecache
+    with global_lock:
+        res1 = cache.get(key)
+        if res1 is None:
+            cache[key] = res
+            return res
+        else:
+            return res1
+
+def pointer_cache(ffi, BType):
+    return global_cache('?', ffi, 'new_pointer_type', BType)
+
+def attach_exception_info(e, name):
+    if e.args and type(e.args[0]) is str:
+        e.args = ('%s: %s' % (name, e.args[0]),) + e.args[1:]

venv/Lib/site-packages/cffi/pkgconfig.py

@@ -0,0 +1,121 @@
+# pkg-config, https://www.freedesktop.org/wiki/Software/pkg-config/ integration for cffi
+import sys, os, subprocess
+
+from .error import PkgConfigError
+
+
+def merge_flags(cfg1, cfg2):
+    """Merge values from cffi config flags cfg2 to cf1
+
+    Example:
+        merge_flags({"libraries": ["one"]}, {"libraries": ["two"]})
+        {"libraries": ["one", "two"]}
+    """
+    for key, value in cfg2.items():
+        if key not in cfg1:
+            cfg1[key] = value
+        else:
+            if not isinstance(cfg1[key], list):
+                raise TypeError("cfg1[%r] should be a list of strings" % (key,))
+            if not isinstance(value, list):
+                raise TypeError("cfg2[%r] should be a list of strings" % (key,))
+            cfg1[key].extend(value)
+    return cfg1
+
+
+def call(libname, flag, encoding=sys.getfilesystemencoding()):
+    """Calls pkg-config and returns the output if found
+    """
+    a = ["pkg-config", "--print-errors"]
+    a.append(flag)
+    a.append(libname)
+    try:
+        pc = subprocess.Popen(a, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+    except EnvironmentError as e:
+        raise PkgConfigError("cannot run pkg-config: %s" % (str(e).strip(),))
+
+    bout, berr = pc.communicate()
+    if pc.returncode != 0:
+        try:
+            berr = berr.decode(encoding)
+        except Exception:
+            pass
+        raise PkgConfigError(berr.strip())
+
+    if sys.version_info >= (3,) and not isinstance(bout, str):   # Python 3.x
+        try:
+            bout = bout.decode(encoding)
+        except UnicodeDecodeError:
+            raise PkgConfigError("pkg-config %s %s returned bytes that cannot "
+                                 "be decoded with encoding %r:\n%r" %
+                                 (flag, libname, encoding, bout))
+
+    if os.altsep != '\\' and '\\' in bout:
+        raise PkgConfigError("pkg-config %s %s returned an unsupported "
+                             "backslash-escaped output:\n%r" %
+                             (flag, libname, bout))
+    return bout
+
+
+def flags_from_pkgconfig(libs):
+    r"""Return compiler line flags for FFI.set_source based on pkg-config output
+
+    Usage
+        ...
+        ffibuilder.set_source("_foo", pkgconfig = ["libfoo", "libbar >= 1.8.3"])
+
+    If pkg-config is installed on build machine, then arguments include_dirs,
+    library_dirs, libraries, define_macros, extra_compile_args and
+    extra_link_args are extended with an output of pkg-config for libfoo and
+    libbar.
+
+    Raises PkgConfigError in case the pkg-config call fails.
+    """
+
+    def get_include_dirs(string):
+        return [x[2:] for x in string.split() if x.startswith("-I")]
+
+    def get_library_dirs(string):
+        return [x[2:] for x in string.split() if x.startswith("-L")]
+
+    def get_libraries(string):
+        return [x[2:] for x in string.split() if x.startswith("-l")]
+
+    # convert -Dfoo=bar to list of tuples [("foo", "bar")] expected by distutils
+    def get_macros(string):
+        def _macro(x):
+            x = x[2:]    # drop "-D"
+            if '=' in x:
+                return tuple(x.split("=", 1))  # "-Dfoo=bar" => ("foo", "bar")
+            else:
+                return (x, None)               # "-Dfoo" => ("foo", None)
+        return [_macro(x) for x in string.split() if x.startswith("-D")]
+
+    def get_other_cflags(string):
+        return [x for x in string.split() if not x.startswith("-I") and
+                                             not x.startswith("-D")]
+
+    def get_other_libs(string):
+        return [x for x in string.split() if not x.startswith("-L") and
+                                             not x.startswith("-l")]
+
+    # return kwargs for given libname
+    def kwargs(libname):
+        fse = sys.getfilesystemencoding()
+        all_cflags = call(libname, "--cflags")
+        all_libs = call(libname, "--libs")
+        return {
+            "include_dirs": get_include_dirs(all_cflags),
+            "library_dirs": get_library_dirs(all_libs),
+            "libraries": get_libraries(all_libs),
+            "define_macros": get_macros(all_cflags),
+            "extra_compile_args": get_other_cflags(all_cflags),
+            "extra_link_args": get_other_libs(all_libs),
+            }
+
+    # merge all arguments together
+    ret = {}
+    for libname in libs:
+        lib_flags = kwargs(libname)
+        merge_flags(ret, lib_flags)
+    return ret

venv/Lib/site-packages/cffi/setuptools_ext.py

@@ -0,0 +1,219 @@
+import os
+import sys
+
+try:
+    basestring
+except NameError:
+    # Python 3.x
+    basestring = str
+
+def error(msg):
+    from distutils.errors import DistutilsSetupError
+    raise DistutilsSetupError(msg)
+
+
+def execfile(filename, glob):
+    # We use execfile() (here rewritten for Python 3) instead of
+    # __import__() to load the build script.  The problem with
+    # a normal import is that in some packages, the intermediate
+    # __init__.py files may already try to import the file that
+    # we are generating.
+    with open(filename) as f:
+        src = f.read()
+    src += '\n'      # Python 2.6 compatibility
+    code = compile(src, filename, 'exec')
+    exec(code, glob, glob)
+
+
+def add_cffi_module(dist, mod_spec):
+    from cffi.api import FFI
+
+    if not isinstance(mod_spec, basestring):
+        error("argument to 'cffi_modules=...' must be a str or a list of str,"
+              " not %r" % (type(mod_spec).__name__,))
+    mod_spec = str(mod_spec)
+    try:
+        build_file_name, ffi_var_name = mod_spec.split(':')
+    except ValueError:
+        error("%r must be of the form 'path/build.py:ffi_variable'" %
+              (mod_spec,))
+    if not os.path.exists(build_file_name):
+        ext = ''
+        rewritten = build_file_name.replace('.', '/') + '.py'
+        if os.path.exists(rewritten):
+            ext = ' (rewrite cffi_modules to [%r])' % (
+                rewritten + ':' + ffi_var_name,)
+        error("%r does not name an existing file%s" % (build_file_name, ext))
+
+    mod_vars = {'__name__': '__cffi__', '__file__': build_file_name}
+    execfile(build_file_name, mod_vars)
+
+    try:
+        ffi = mod_vars[ffi_var_name]
+    except KeyError:
+        error("%r: object %r not found in module" % (mod_spec,
+                                                     ffi_var_name))
+    if not isinstance(ffi, FFI):
+        ffi = ffi()      # maybe it's a function instead of directly an ffi
+    if not isinstance(ffi, FFI):
+        error("%r is not an FFI instance (got %r)" % (mod_spec,
+                                                      type(ffi).__name__))
+    if not hasattr(ffi, '_assigned_source'):
+        error("%r: the set_source() method was not called" % (mod_spec,))
+    module_name, source, source_extension, kwds = ffi._assigned_source
+    if ffi._windows_unicode:
+        kwds = kwds.copy()
+        ffi._apply_windows_unicode(kwds)
+
+    if source is None:
+        _add_py_module(dist, ffi, module_name)
+    else:
+        _add_c_module(dist, ffi, module_name, source, source_extension, kwds)
+
+def _set_py_limited_api(Extension, kwds):
+    """
+    Add py_limited_api to kwds if setuptools >= 26 is in use.
+    Do not alter the setting if it already exists.
+    Setuptools takes care of ignoring the flag on Python 2 and PyPy.
+
+    CPython itself should ignore the flag in a debugging version
+    (by not listing .abi3.so in the extensions it supports), but
+    it doesn't so far, creating troubles.  That's why we check
+    for "not hasattr(sys, 'gettotalrefcount')" (the 2.7 compatible equivalent
+    of 'd' not in sys.abiflags). (http://bugs.python.org/issue28401)
+
+    On Windows, with CPython <= 3.4, it's better not to use py_limited_api
+    because virtualenv *still* doesn't copy PYTHON3.DLL on these versions.
+    Recently (2020) we started shipping only >= 3.5 wheels, though.  So
+    we'll give it another try and set py_limited_api on Windows >= 3.5.
+    """
+    from cffi import recompiler
+
+    if ('py_limited_api' not in kwds and not hasattr(sys, 'gettotalrefcount')
+            and recompiler.USE_LIMITED_API):
+        import setuptools
+        try:
+            setuptools_major_version = int(setuptools.__version__.partition('.')[0])
+            if setuptools_major_version >= 26:
+                kwds['py_limited_api'] = True
+        except ValueError:  # certain development versions of setuptools
+            # If we don't know the version number of setuptools, we
+            # try to set 'py_limited_api' anyway.  At worst, we get a
+            # warning.
+            kwds['py_limited_api'] = True
+    return kwds
+
+def _add_c_module(dist, ffi, module_name, source, source_extension, kwds):
+    from distutils.core import Extension
+    # We are a setuptools extension. Need this build_ext for py_limited_api.
+    from setuptools.command.build_ext import build_ext
+    from distutils.dir_util import mkpath
+    from distutils import log
+    from cffi import recompiler
+
+    allsources = ['$PLACEHOLDER']
+    allsources.extend(kwds.pop('sources', []))
+    kwds = _set_py_limited_api(Extension, kwds)
+    ext = Extension(name=module_name, sources=allsources, **kwds)
+
+    def make_mod(tmpdir, pre_run=None):
+        c_file = os.path.join(tmpdir, module_name + source_extension)
+        log.info("generating cffi module %r" % c_file)
+        mkpath(tmpdir)
+        # a setuptools-only, API-only hook: called with the "ext" and "ffi"
+        # arguments just before we turn the ffi into C code.  To use it,
+        # subclass the 'distutils.command.build_ext.build_ext' class and
+        # add a method 'def pre_run(self, ext, ffi)'.
+        if pre_run is not None:
+            pre_run(ext, ffi)
+        updated = recompiler.make_c_source(ffi, module_name, source, c_file)
+        if not updated:
+            log.info("already up-to-date")
+        return c_file
+
+    if dist.ext_modules is None:
+        dist.ext_modules = []
+    dist.ext_modules.append(ext)
+
+    base_class = dist.cmdclass.get('build_ext', build_ext)
+    class build_ext_make_mod(base_class):
+        def run(self):
+            if ext.sources[0] == '$PLACEHOLDER':
+                pre_run = getattr(self, 'pre_run', None)
+                ext.sources[0] = make_mod(self.build_temp, pre_run)
+            base_class.run(self)
+    dist.cmdclass['build_ext'] = build_ext_make_mod
+    # NB. multiple runs here will create multiple 'build_ext_make_mod'
+    # classes.  Even in this case the 'build_ext' command should be
+    # run once; but just in case, the logic above does nothing if
+    # called again.
+
+
+def _add_py_module(dist, ffi, module_name):
+    from distutils.dir_util import mkpath
+    from setuptools.command.build_py import build_py
+    from setuptools.command.build_ext import build_ext
+    from distutils import log
+    from cffi import recompiler
+
+    def generate_mod(py_file):
+        log.info("generating cffi module %r" % py_file)
+        mkpath(os.path.dirname(py_file))
+        updated = recompiler.make_py_source(ffi, module_name, py_file)
+        if not updated:
+            log.info("already up-to-date")
+
+    base_class = dist.cmdclass.get('build_py', build_py)
+    class build_py_make_mod(base_class):
+        def run(self):
+            base_class.run(self)
+            module_path = module_name.split('.')
+            module_path[-1] += '.py'
+            generate_mod(os.path.join(self.build_lib, *module_path))
+        def get_source_files(self):
+            # This is called from 'setup.py sdist' only.  Exclude
+            # the generate .py module in this case.
+            saved_py_modules = self.py_modules
+            try:
+                if saved_py_modules:
+                    self.py_modules = [m for m in saved_py_modules
+                                         if m != module_name]
+                return base_class.get_source_files(self)
+            finally:
+                self.py_modules = saved_py_modules
+    dist.cmdclass['build_py'] = build_py_make_mod
+
+    # distutils and setuptools have no notion I could find of a
+    # generated python module.  If we don't add module_name to
+    # dist.py_modules, then things mostly work but there are some
+    # combination of options (--root and --record) that will miss
+    # the module.  So we add it here, which gives a few apparently
+    # harmless warnings about not finding the file outside the
+    # build directory.
+    # Then we need to hack more in get_source_files(); see above.
+    if dist.py_modules is None:
+        dist.py_modules = []
+    dist.py_modules.append(module_name)
+
+    # the following is only for "build_ext -i"
+    base_class_2 = dist.cmdclass.get('build_ext', build_ext)
+    class build_ext_make_mod(base_class_2):
+        def run(self):
+            base_class_2.run(self)
+            if self.inplace:
+                # from get_ext_fullpath() in distutils/command/build_ext.py
+                module_path = module_name.split('.')
+                package = '.'.join(module_path[:-1])
+                build_py = self.get_finalized_command('build_py')
+                package_dir = build_py.get_package_dir(package)
+                file_name = module_path[-1] + '.py'
+                generate_mod(os.path.join(package_dir, file_name))
+    dist.cmdclass['build_ext'] = build_ext_make_mod
+
+def cffi_modules(dist, attr, value):
+    assert attr == 'cffi_modules'
+    if isinstance(value, basestring):
+        value = [value]
+
+    for cffi_module in value:
+        add_cffi_module(dist, cffi_module)

venv/Lib/site-packages/cffi/vengine_gen.py

@@ -0,0 +1,675 @@
+#
+# DEPRECATED: implementation for ffi.verify()
+#
+import sys, os
+import types
+
+from . import model
+from .error import VerificationError
+
+
+class VGenericEngine(object):
+    _class_key = 'g'
+    _gen_python_module = False
+
+    def __init__(self, verifier):
+        self.verifier = verifier
+        self.ffi = verifier.ffi
+        self.export_symbols = []
+        self._struct_pending_verification = {}
+
+    def patch_extension_kwds(self, kwds):
+        # add 'export_symbols' to the dictionary.  Note that we add the
+        # list before filling it.  When we fill it, it will thus also show
+        # up in kwds['export_symbols'].
+        kwds.setdefault('export_symbols', self.export_symbols)
+
+    def find_module(self, module_name, path, so_suffixes):
+        for so_suffix in so_suffixes:
+            basename = module_name + so_suffix
+            if path is None:
+                path = sys.path
+            for dirname in path:
+                filename = os.path.join(dirname, basename)
+                if os.path.isfile(filename):
+                    return filename
+
+    def collect_types(self):
+        pass      # not needed in the generic engine
+
+    def _prnt(self, what=''):
+        self._f.write(what + '\n')
+
+    def write_source_to_f(self):
+        prnt = self._prnt
+        # first paste some standard set of lines that are mostly '#include'
+        prnt(cffimod_header)
+        # then paste the C source given by the user, verbatim.
+        prnt(self.verifier.preamble)
+        #
+        # call generate_gen_xxx_decl(), for every xxx found from
+        # ffi._parser._declarations.  This generates all the functions.
+        self._generate('decl')
+        #
+        # on Windows, distutils insists on putting init_cffi_xyz in
+        # 'export_symbols', so instead of fighting it, just give up and
+        # give it one
+        if sys.platform == 'win32':
+            if sys.version_info >= (3,):
+                prefix = 'PyInit_'
+            else:
+                prefix = 'init'
+            modname = self.verifier.get_module_name()
+            prnt("void %s%s(void) { }\n" % (prefix, modname))
+
+    def load_library(self, flags=0):
+        # import it with the CFFI backend
+        backend = self.ffi._backend
+        # needs to make a path that contains '/', on Posix
+        filename = os.path.join(os.curdir, self.verifier.modulefilename)
+        module = backend.load_library(filename, flags)
+        #
+        # call loading_gen_struct() to get the struct layout inferred by
+        # the C compiler
+        self._load(module, 'loading')
+
+        # build the FFILibrary class and instance, this is a module subclass
+        # because modules are expected to have usually-constant-attributes and
+        # in PyPy this means the JIT is able to treat attributes as constant,
+        # which we want.
+        class FFILibrary(types.ModuleType):
+            _cffi_generic_module = module
+            _cffi_ffi = self.ffi
+            _cffi_dir = []
+            def __dir__(self):
+                return FFILibrary._cffi_dir
+        library = FFILibrary("")
+        #
+        # finally, call the loaded_gen_xxx() functions.  This will set
+        # up the 'library' object.
+        self._load(module, 'loaded', library=library)
+        return library
+
+    def _get_declarations(self):
+        lst = [(key, tp) for (key, (tp, qual)) in
+                                self.ffi._parser._declarations.items()]
+        lst.sort()
+        return lst
+
+    def _generate(self, step_name):
+        for name, tp in self._get_declarations():
+            kind, realname = name.split(' ', 1)
+            try:
+                method = getattr(self, '_generate_gen_%s_%s' % (kind,
+                                                                step_name))
+            except AttributeError:
+                raise VerificationError(
+                    "not implemented in verify(): %r" % name)
+            try:
+                method(tp, realname)
+            except Exception as e:
+                model.attach_exception_info(e, name)
+                raise
+
+    def _load(self, module, step_name, **kwds):
+        for name, tp in self._get_declarations():
+            kind, realname = name.split(' ', 1)
+            method = getattr(self, '_%s_gen_%s' % (step_name, kind))
+            try:
+                method(tp, realname, module, **kwds)
+            except Exception as e:
+                model.attach_exception_info(e, name)
+                raise
+
+    def _generate_nothing(self, tp, name):
+        pass
+
+    def _loaded_noop(self, tp, name, module, **kwds):
+        pass
+
+    # ----------
+    # typedefs: generates no code so far
+
+    _generate_gen_typedef_decl   = _generate_nothing
+    _loading_gen_typedef         = _loaded_noop
+    _loaded_gen_typedef          = _loaded_noop
+
+    # ----------
+    # function declarations
+
+    def _generate_gen_function_decl(self, tp, name):
+        assert isinstance(tp, model.FunctionPtrType)
+        if tp.ellipsis:
+            # cannot support vararg functions better than this: check for its
+            # exact type (including the fixed arguments), and build it as a
+            # constant function pointer (no _cffi_f_%s wrapper)
+            self._generate_gen_const(False, name, tp)
+            return
+        prnt = self._prnt
+        numargs = len(tp.args)
+        argnames = []
+        for i, type in enumerate(tp.args):
+            indirection = ''
+            if isinstance(type, model.StructOrUnion):
+                indirection = '*'
+            argnames.append('%sx%d' % (indirection, i))
+        context = 'argument of %s' % name
+        arglist = [type.get_c_name(' %s' % arg, context)
+                   for type, arg in zip(tp.args, argnames)]
+        tpresult = tp.result
+        if isinstance(tpresult, model.StructOrUnion):
+            arglist.insert(0, tpresult.get_c_name(' *r', context))
+            tpresult = model.void_type
+        arglist = ', '.join(arglist) or 'void'
+        wrappername = '_cffi_f_%s' % name
+        self.export_symbols.append(wrappername)
+        if tp.abi:
+            abi = tp.abi + ' '
+        else:
+            abi = ''
+        funcdecl = ' %s%s(%s)' % (abi, wrappername, arglist)
+        context = 'result of %s' % name
+        prnt(tpresult.get_c_name(funcdecl, context))
+        prnt('{')
+        #
+        if isinstance(tp.result, model.StructOrUnion):
+            result_code = '*r = '
+        elif not isinstance(tp.result, model.VoidType):
+            result_code = 'return '
+        else:
+            result_code = ''
+        prnt('  %s%s(%s);' % (result_code, name, ', '.join(argnames)))
+        prnt('}')
+        prnt()
+
+    _loading_gen_function = _loaded_noop
+
+    def _loaded_gen_function(self, tp, name, module, library):
+        assert isinstance(tp, model.FunctionPtrType)
+        if tp.ellipsis:
+            newfunction = self._load_constant(False, tp, name, module)
+        else:
+            indirections = []
+            base_tp = tp
+            if (any(isinstance(typ, model.StructOrUnion) for typ in tp.args)
+                    or isinstance(tp.result, model.StructOrUnion)):
+                indirect_args = []
+                for i, typ in enumerate(tp.args):
+                    if isinstance(typ, model.StructOrUnion):
+                        typ = model.PointerType(typ)
+                        indirections.append((i, typ))
+                    indirect_args.append(typ)
+                indirect_result = tp.result
+                if isinstance(indirect_result, model.StructOrUnion):
+                    if indirect_result.fldtypes is None:
+                        raise TypeError("'%s' is used as result type, "
+                                        "but is opaque" % (
+                                            indirect_result._get_c_name(),))
+                    indirect_result = model.PointerType(indirect_result)
+                    indirect_args.insert(0, indirect_result)
+                    indirections.insert(0, ("result", indirect_result))
+                    indirect_result = model.void_type
+                tp = model.FunctionPtrType(tuple(indirect_args),
+                                           indirect_result, tp.ellipsis)
+            BFunc = self.ffi._get_cached_btype(tp)
+            wrappername = '_cffi_f_%s' % name
+            newfunction = module.load_function(BFunc, wrappername)
+            for i, typ in indirections:
+                newfunction = self._make_struct_wrapper(newfunction, i, typ,
+                                                        base_tp)
+        setattr(library, name, newfunction)
+        type(library)._cffi_dir.append(name)
+
+    def _make_struct_wrapper(self, oldfunc, i, tp, base_tp):
+        backend = self.ffi._backend
+        BType = self.ffi._get_cached_btype(tp)
+        if i == "result":
+            ffi = self.ffi
+            def newfunc(*args):
+                res = ffi.new(BType)
+                oldfunc(res, *args)
+                return res[0]
+        else:
+            def newfunc(*args):
+                args = args[:i] + (backend.newp(BType, args[i]),) + args[i+1:]
+                return oldfunc(*args)
+        newfunc._cffi_base_type = base_tp
+        return newfunc
+
+    # ----------
+    # named structs
+
+    def _generate_gen_struct_decl(self, tp, name):
+        assert name == tp.name
+        self._generate_struct_or_union_decl(tp, 'struct', name)
+
+    def _loading_gen_struct(self, tp, name, module):
+        self._loading_struct_or_union(tp, 'struct', name, module)
+
+    def _loaded_gen_struct(self, tp, name, module, **kwds):
+        self._loaded_struct_or_union(tp)
+
+    def _generate_gen_union_decl(self, tp, name):
+        assert name == tp.name
+        self._generate_struct_or_union_decl(tp, 'union', name)
+
+    def _loading_gen_union(self, tp, name, module):
+        self._loading_struct_or_union(tp, 'union', name, module)
+
+    def _loaded_gen_union(self, tp, name, module, **kwds):
+        self._loaded_struct_or_union(tp)
+
+    def _generate_struct_or_union_decl(self, tp, prefix, name):
+        if tp.fldnames is None:
+            return     # nothing to do with opaque structs
+        checkfuncname = '_cffi_check_%s_%s' % (prefix, name)
+        layoutfuncname = '_cffi_layout_%s_%s' % (prefix, name)
+        cname = ('%s %s' % (prefix, name)).strip()
+        #
+        prnt = self._prnt
+        prnt('static void %s(%s *p)' % (checkfuncname, cname))
+        prnt('{')
+        prnt('  /* only to generate compile-time warnings or errors */')
+        prnt('  (void)p;')
+        for fname, ftype, fbitsize, fqual in tp.enumfields():
+            if (isinstance(ftype, model.PrimitiveType)
+                and ftype.is_integer_type()) or fbitsize >= 0:
+                # accept all integers, but complain on float or double
+                prnt('  (void)((p->%s) << 1);' % fname)
+            else:
+                # only accept exactly the type declared.
+                try:
+                    prnt('  { %s = &p->%s; (void)tmp; }' % (
+                        ftype.get_c_name('*tmp', 'field %r'%fname, quals=fqual),
+                        fname))
+                except VerificationError as e:
+                    prnt('  /* %s */' % str(e))   # cannot verify it, ignore
+        prnt('}')
+        self.export_symbols.append(layoutfuncname)
+        prnt('intptr_t %s(intptr_t i)' % (layoutfuncname,))
+        prnt('{')
+        prnt('  struct _cffi_aligncheck { char x; %s y; };' % cname)
+        prnt('  static intptr_t nums[] = {')
+        prnt('    sizeof(%s),' % cname)
+        prnt('    offsetof(struct _cffi_aligncheck, y),')
+        for fname, ftype, fbitsize, fqual in tp.enumfields():
+            if fbitsize >= 0:
+                continue      # xxx ignore fbitsize for now
+            prnt('    offsetof(%s, %s),' % (cname, fname))
+            if isinstance(ftype, model.ArrayType) and ftype.length is None:
+                prnt('    0,  /* %s */' % ftype._get_c_name())
+            else:
+                prnt('    sizeof(((%s *)0)->%s),' % (cname, fname))
+        prnt('    -1')
+        prnt('  };')
+        prnt('  return nums[i];')
+        prnt('  /* the next line is not executed, but compiled */')
+        prnt('  %s(0);' % (checkfuncname,))
+        prnt('}')
+        prnt()
+
+    def _loading_struct_or_union(self, tp, prefix, name, module):
+        if tp.fldnames is None:
+            return     # nothing to do with opaque structs
+        layoutfuncname = '_cffi_layout_%s_%s' % (prefix, name)
+        #
+        BFunc = self.ffi._typeof_locked("intptr_t(*)(intptr_t)")[0]
+        function = module.load_function(BFunc, layoutfuncname)
+        layout = []
+        num = 0
+        while True:
+            x = function(num)
+            if x < 0: break
+            layout.append(x)
+            num += 1
+        if isinstance(tp, model.StructOrUnion) and tp.partial:
+            # use the function()'s sizes and offsets to guide the
+            # layout of the struct
+            totalsize = layout[0]
+            totalalignment = layout[1]
+            fieldofs = layout[2::2]
+            fieldsize = layout[3::2]
+            tp.force_flatten()
+            assert len(fieldofs) == len(fieldsize) == len(tp.fldnames)
+            tp.fixedlayout = fieldofs, fieldsize, totalsize, totalalignment
+        else:
+            cname = ('%s %s' % (prefix, name)).strip()
+            self._struct_pending_verification[tp] = layout, cname
+
+    def _loaded_struct_or_union(self, tp):
+        if tp.fldnames is None:
+            return     # nothing to do with opaque structs
+        self.ffi._get_cached_btype(tp)   # force 'fixedlayout' to be considered
+
+        if tp in self._struct_pending_verification:
+            # check that the layout sizes and offsets match the real ones
+            def check(realvalue, expectedvalue, msg):
+                if realvalue != expectedvalue:
+                    raise VerificationError(
+                        "%s (we have %d, but C compiler says %d)"
+                        % (msg, expectedvalue, realvalue))
+            ffi = self.ffi
+            BStruct = ffi._get_cached_btype(tp)
+            layout, cname = self._struct_pending_verification.pop(tp)
+            check(layout[0], ffi.sizeof(BStruct), "wrong total size")
+            check(layout[1], ffi.alignof(BStruct), "wrong total alignment")
+            i = 2
+            for fname, ftype, fbitsize, fqual in tp.enumfields():
+                if fbitsize >= 0:
+                    continue        # xxx ignore fbitsize for now
+                check(layout[i], ffi.offsetof(BStruct, fname),
+                      "wrong offset for field %r" % (fname,))
+                if layout[i+1] != 0:
+                    BField = ffi._get_cached_btype(ftype)
+                    check(layout[i+1], ffi.sizeof(BField),
+                          "wrong size for field %r" % (fname,))
+                i += 2
+            assert i == len(layout)
+
+    # ----------
+    # 'anonymous' declarations.  These are produced for anonymous structs
+    # or unions; the 'name' is obtained by a typedef.
+
+    def _generate_gen_anonymous_decl(self, tp, name):
+        if isinstance(tp, model.EnumType):
+            self._generate_gen_enum_decl(tp, name, '')
+        else:
+            self._generate_struct_or_union_decl(tp, '', name)
+
+    def _loading_gen_anonymous(self, tp, name, module):
+        if isinstance(tp, model.EnumType):
+            self._loading_gen_enum(tp, name, module, '')
+        else:
+            self._loading_struct_or_union(tp, '', name, module)
+
+    def _loaded_gen_anonymous(self, tp, name, module, **kwds):
+        if isinstance(tp, model.EnumType):
+            self._loaded_gen_enum(tp, name, module, **kwds)
+        else:
+            self._loaded_struct_or_union(tp)
+
+    # ----------
+    # constants, likely declared with '#define'
+
+    def _generate_gen_const(self, is_int, name, tp=None, category='const',
+                            check_value=None):
+        prnt = self._prnt
+        funcname = '_cffi_%s_%s' % (category, name)
+        self.export_symbols.append(funcname)
+        if check_value is not None:
+            assert is_int
+            assert category == 'const'
+            prnt('int %s(char *out_error)' % funcname)
+            prnt('{')
+            self._check_int_constant_value(name, check_value)
+            prnt('  return 0;')
+            prnt('}')
+        elif is_int:
+            assert category == 'const'
+            prnt('int %s(long long *out_value)' % funcname)
+            prnt('{')
+            prnt('  *out_value = (long long)(%s);' % (name,))
+            prnt('  return (%s) <= 0;' % (name,))
+            prnt('}')
+        else:
+            assert tp is not None
+            assert check_value is None
+            if category == 'var':
+                ampersand = '&'
+            else:
+                ampersand = ''
+            extra = ''
+            if category == 'const' and isinstance(tp, model.StructOrUnion):
+                extra = 'const *'
+                ampersand = '&'
+            prnt(tp.get_c_name(' %s%s(void)' % (extra, funcname), name))
+            prnt('{')
+            prnt('  return (%s%s);' % (ampersand, name))
+            prnt('}')
+        prnt()
+
+    def _generate_gen_constant_decl(self, tp, name):
+        is_int = isinstance(tp, model.PrimitiveType) and tp.is_integer_type()
+        self._generate_gen_const(is_int, name, tp)
+
+    _loading_gen_constant = _loaded_noop
+
+    def _load_constant(self, is_int, tp, name, module, check_value=None):
+        funcname = '_cffi_const_%s' % name
+        if check_value is not None:
+            assert is_int
+            self._load_known_int_constant(module, funcname)
+            value = check_value
+        elif is_int:
+            BType = self.ffi._typeof_locked("long long*")[0]
+            BFunc = self.ffi._typeof_locked("int(*)(long long*)")[0]
+            function = module.load_function(BFunc, funcname)
+            p = self.ffi.new(BType)
+            negative = function(p)
+            value = int(p[0])
+            if value < 0 and not negative:
+                BLongLong = self.ffi._typeof_locked("long long")[0]
+                value += (1 << (8*self.ffi.sizeof(BLongLong)))
+        else:
+            assert check_value is None
+            fntypeextra = '(*)(void)'
+            if isinstance(tp, model.StructOrUnion):
+                fntypeextra = '*' + fntypeextra
+            BFunc = self.ffi._typeof_locked(tp.get_c_name(fntypeextra, name))[0]
+            function = module.load_function(BFunc, funcname)
+            value = function()
+            if isinstance(tp, model.StructOrUnion):
+                value = value[0]
+        return value
+
+    def _loaded_gen_constant(self, tp, name, module, library):
+        is_int = isinstance(tp, model.PrimitiveType) and tp.is_integer_type()
+        value = self._load_constant(is_int, tp, name, module)
+        setattr(library, name, value)
+        type(library)._cffi_dir.append(name)
+
+    # ----------
+    # enums
+
+    def _check_int_constant_value(self, name, value):
+        prnt = self._prnt
+        if value <= 0:
+            prnt('  if ((%s) > 0 || (long)(%s) != %dL) {' % (
+                name, name, value))
+        else:
+            prnt('  if ((%s) <= 0 || (unsigned long)(%s) != %dUL) {' % (
+                name, name, value))
+        prnt('    char buf[64];')
+        prnt('    if ((%s) <= 0)' % name)
+        prnt('        sprintf(buf, "%%ld", (long)(%s));' % name)
+        prnt('    else')
+        prnt('        sprintf(buf, "%%lu", (unsigned long)(%s));' %
+             name)
+        prnt('    sprintf(out_error, "%s has the real value %s, not %s",')
+        prnt('            "%s", buf, "%d");' % (name[:100], value))
+        prnt('    return -1;')
+        prnt('  }')
+
+    def _load_known_int_constant(self, module, funcname):
+        BType = self.ffi._typeof_locked("char[]")[0]
+        BFunc = self.ffi._typeof_locked("int(*)(char*)")[0]
+        function = module.load_function(BFunc, funcname)
+        p = self.ffi.new(BType, 256)
+        if function(p) < 0:
+            error = self.ffi.string(p)
+            if sys.version_info >= (3,):
+                error = str(error, 'utf-8')
+            raise VerificationError(error)
+
+    def _enum_funcname(self, prefix, name):
+        # "$enum_$1" => "___D_enum____D_1"
+        name = name.replace('$', '___D_')
+        return '_cffi_e_%s_%s' % (prefix, name)
+
+    def _generate_gen_enum_decl(self, tp, name, prefix='enum'):
+        if tp.partial:
+            for enumerator in tp.enumerators:
+                self._generate_gen_const(True, enumerator)
+            return
+        #
+        funcname = self._enum_funcname(prefix, name)
+        self.export_symbols.append(funcname)
+        prnt = self._prnt
+        prnt('int %s(char *out_error)' % funcname)
+        prnt('{')
+        for enumerator, enumvalue in zip(tp.enumerators, tp.enumvalues):
+            self._check_int_constant_value(enumerator, enumvalue)
+        prnt('  return 0;')
+        prnt('}')
+        prnt()
+
+    def _loading_gen_enum(self, tp, name, module, prefix='enum'):
+        if tp.partial:
+            enumvalues = [self._load_constant(True, tp, enumerator, module)
+                          for enumerator in tp.enumerators]
+            tp.enumvalues = tuple(enumvalues)
+            tp.partial_resolved = True
+        else:
+            funcname = self._enum_funcname(prefix, name)
+            self._load_known_int_constant(module, funcname)
+
+    def _loaded_gen_enum(self, tp, name, module, library):
+        for enumerator, enumvalue in zip(tp.enumerators, tp.enumvalues):
+            setattr(library, enumerator, enumvalue)
+            type(library)._cffi_dir.append(enumerator)
+
+    # ----------
+    # macros: for now only for integers
+
+    def _generate_gen_macro_decl(self, tp, name):
+        if tp == '...':
+            check_value = None
+        else:
+            check_value = tp     # an integer
+        self._generate_gen_const(True, name, check_value=check_value)
+
+    _loading_gen_macro = _loaded_noop
+
+    def _loaded_gen_macro(self, tp, name, module, library):
+        if tp == '...':
+            check_value = None
+        else:
+            check_value = tp     # an integer
+        value = self._load_constant(True, tp, name, module,
+                                    check_value=check_value)
+        setattr(library, name, value)
+        type(library)._cffi_dir.append(name)
+
+    # ----------
+    # global variables
+
+    def _generate_gen_variable_decl(self, tp, name):
+        if isinstance(tp, model.ArrayType):
+            if tp.length_is_unknown():
+                prnt = self._prnt
+                funcname = '_cffi_sizeof_%s' % (name,)
+                self.export_symbols.append(funcname)
+                prnt("size_t %s(void)" % funcname)
+                prnt("{")
+                prnt("  return sizeof(%s);" % (name,))
+                prnt("}")
+            tp_ptr = model.PointerType(tp.item)
+            self._generate_gen_const(False, name, tp_ptr)
+        else:
+            tp_ptr = model.PointerType(tp)
+            self._generate_gen_const(False, name, tp_ptr, category='var')
+
+    _loading_gen_variable = _loaded_noop
+
+    def _loaded_gen_variable(self, tp, name, module, library):
+        if isinstance(tp, model.ArrayType):   # int a[5] is "constant" in the
+                                              # sense that "a=..." is forbidden
+            if tp.length_is_unknown():
+                funcname = '_cffi_sizeof_%s' % (name,)
+                BFunc = self.ffi._typeof_locked('size_t(*)(void)')[0]
+                function = module.load_function(BFunc, funcname)
+                size = function()
+                BItemType = self.ffi._get_cached_btype(tp.item)
+                length, rest = divmod(size, self.ffi.sizeof(BItemType))
+                if rest != 0:
+                    raise VerificationError(
+                        "bad size: %r does not seem to be an array of %s" %
+                        (name, tp.item))
+                tp = tp.resolve_length(length)
+            tp_ptr = model.PointerType(tp.item)
+            value = self._load_constant(False, tp_ptr, name, module)
+            # 'value' is a <cdata 'type *'> which we have to replace with
+            # a <cdata 'type[N]'> if the N is actually known
+            if tp.length is not None:
+                BArray = self.ffi._get_cached_btype(tp)
+                value = self.ffi.cast(BArray, value)
+            setattr(library, name, value)
+            type(library)._cffi_dir.append(name)
+            return
+        # remove ptr=<cdata 'int *'> from the library instance, and replace
+        # it by a property on the class, which reads/writes into ptr[0].
+        funcname = '_cffi_var_%s' % name
+        BFunc = self.ffi._typeof_locked(tp.get_c_name('*(*)(void)', name))[0]
+        function = module.load_function(BFunc, funcname)
+        ptr = function()
+        def getter(library):
+            return ptr[0]
+        def setter(library, value):
+            ptr[0] = value
+        setattr(type(library), name, property(getter, setter))
+        type(library)._cffi_dir.append(name)
+
+cffimod_header = r'''
+#include <stdio.h>
+#include <stddef.h>
+#include <stdarg.h>
+#include <errno.h>
+#include <sys/types.h>   /* XXX for ssize_t on some platforms */
+
+/* this block of #ifs should be kept exactly identical between
+   c/_cffi_backend.c, cffi/vengine_cpy.py, cffi/vengine_gen.py
+   and cffi/_cffi_include.h */
+#if defined(_MSC_VER)
+# include <malloc.h>   /* for alloca() */
+# if _MSC_VER < 1600   /* MSVC < 2010 */
+   typedef __int8 int8_t;
+   typedef __int16 int16_t;
+   typedef __int32 int32_t;
+   typedef __int64 int64_t;
+   typedef unsigned __int8 uint8_t;
+   typedef unsigned __int16 uint16_t;
+   typedef unsigned __int32 uint32_t;
+   typedef unsigned __int64 uint64_t;
+   typedef __int8 int_least8_t;
+   typedef __int16 int_least16_t;
+   typedef __int32 int_least32_t;
+   typedef __int64 int_least64_t;
+   typedef unsigned __int8 uint_least8_t;
+   typedef unsigned __int16 uint_least16_t;
+   typedef unsigned __int32 uint_least32_t;
+   typedef unsigned __int64 uint_least64_t;
+   typedef __int8 int_fast8_t;
+   typedef __int16 int_fast16_t;
+   typedef __int32 int_fast32_t;
+   typedef __int64 int_fast64_t;
+   typedef unsigned __int8 uint_fast8_t;
+   typedef unsigned __int16 uint_fast16_t;
+   typedef unsigned __int32 uint_fast32_t;
+   typedef unsigned __int64 uint_fast64_t;
+   typedef __int64 intmax_t;
+   typedef unsigned __int64 uintmax_t;
+# else
+#  include <stdint.h>
+# endif
+# if _MSC_VER < 1800   /* MSVC < 2013 */
+#  ifndef __cplusplus
+    typedef unsigned char _Bool;
+#  endif
+# endif
+#else
+# include <stdint.h>
+# if (defined (__SVR4) && defined (__sun)) || defined(_AIX) || defined(__hpux)
+#  include <alloca.h>
+# endif
+#endif
+'''

venv/Lib/site-packages/cffi/verifier.py

@@ -0,0 +1,307 @@
+#
+# DEPRECATED: implementation for ffi.verify()
+#
+import sys, os, binascii, shutil, io
+from . import __version_verifier_modules__
+from . import ffiplatform
+from .error import VerificationError
+
+if sys.version_info >= (3, 3):
+    import importlib.machinery
+    def _extension_suffixes():
+        return importlib.machinery.EXTENSION_SUFFIXES[:]
+else:
+    import imp
+    def _extension_suffixes():
+        return [suffix for suffix, _, type in imp.get_suffixes()
+                if type == imp.C_EXTENSION]
+
+
+if sys.version_info >= (3,):
+    NativeIO = io.StringIO
+else:
+    class NativeIO(io.BytesIO):
+        def write(self, s):
+            if isinstance(s, unicode):
+                s = s.encode('ascii')
+            super(NativeIO, self).write(s)
+
+
+class Verifier(object):
+
+    def __init__(self, ffi, preamble, tmpdir=None, modulename=None,
+                 ext_package=None, tag='', force_generic_engine=False,
+                 source_extension='.c', flags=None, relative_to=None, **kwds):
+        if ffi._parser._uses_new_feature:
+            raise VerificationError(
+                "feature not supported with ffi.verify(), but only "
+                "with ffi.set_source(): %s" % (ffi._parser._uses_new_feature,))
+        self.ffi = ffi
+        self.preamble = preamble
+        if not modulename:
+            flattened_kwds = ffiplatform.flatten(kwds)
+        vengine_class = _locate_engine_class(ffi, force_generic_engine)
+        self._vengine = vengine_class(self)
+        self._vengine.patch_extension_kwds(kwds)
+        self.flags = flags
+        self.kwds = self.make_relative_to(kwds, relative_to)
+        #
+        if modulename:
+            if tag:
+                raise TypeError("can't specify both 'modulename' and 'tag'")
+        else:
+            key = '\x00'.join(['%d.%d' % sys.version_info[:2],
+                               __version_verifier_modules__,
+                               preamble, flattened_kwds] +
+                              ffi._cdefsources)
+            if sys.version_info >= (3,):
+                key = key.encode('utf-8')
+            k1 = hex(binascii.crc32(key[0::2]) & 0xffffffff)
+            k1 = k1.lstrip('0x').rstrip('L')
+            k2 = hex(binascii.crc32(key[1::2]) & 0xffffffff)
+            k2 = k2.lstrip('0').rstrip('L')
+            modulename = '_cffi_%s_%s%s%s' % (tag, self._vengine._class_key,
+                                              k1, k2)
+        suffix = _get_so_suffixes()[0]
+        self.tmpdir = tmpdir or _caller_dir_pycache()
+        self.sourcefilename = os.path.join(self.tmpdir, modulename + source_extension)
+        self.modulefilename = os.path.join(self.tmpdir, modulename + suffix)
+        self.ext_package = ext_package
+        self._has_source = False
+        self._has_module = False
+
+    def write_source(self, file=None):
+        """Write the C source code.  It is produced in 'self.sourcefilename',
+        which can be tweaked beforehand."""
+        with self.ffi._lock:
+            if self._has_source and file is None:
+                raise VerificationError(
+                    "source code already written")
+            self._write_source(file)
+
+    def compile_module(self):
+        """Write the C source code (if not done already) and compile it.
+        This produces a dynamic link library in 'self.modulefilename'."""
+        with self.ffi._lock:
+            if self._has_module:
+                raise VerificationError("module already compiled")
+            if not self._has_source:
+                self._write_source()
+            self._compile_module()
+
+    def load_library(self):
+        """Get a C module from this Verifier instance.
+        Returns an instance of a FFILibrary class that behaves like the
+        objects returned by ffi.dlopen(), but that delegates all
+        operations to the C module.  If necessary, the C code is written
+        and compiled first.
+        """
+        with self.ffi._lock:
+            if not self._has_module:
+                self._locate_module()
+                if not self._has_module:
+                    if not self._has_source:
+                        self._write_source()
+                    self._compile_module()
+            return self._load_library()
+
+    def get_module_name(self):
+        basename = os.path.basename(self.modulefilename)
+        # kill both the .so extension and the other .'s, as introduced
+        # by Python 3: 'basename.cpython-33m.so'
+        basename = basename.split('.', 1)[0]
+        # and the _d added in Python 2 debug builds --- but try to be
+        # conservative and not kill a legitimate _d
+        if basename.endswith('_d') and hasattr(sys, 'gettotalrefcount'):
+            basename = basename[:-2]
+        return basename
+
+    def get_extension(self):
+        ffiplatform._hack_at_distutils() # backward compatibility hack
+        if not self._has_source:
+            with self.ffi._lock:
+                if not self._has_source:
+                    self._write_source()
+        sourcename = ffiplatform.maybe_relative_path(self.sourcefilename)
+        modname = self.get_module_name()
+        return ffiplatform.get_extension(sourcename, modname, **self.kwds)
+
+    def generates_python_module(self):
+        return self._vengine._gen_python_module
+
+    def make_relative_to(self, kwds, relative_to):
+        if relative_to and os.path.dirname(relative_to):
+            dirname = os.path.dirname(relative_to)
+            kwds = kwds.copy()
+            for key in ffiplatform.LIST_OF_FILE_NAMES:
+                if key in kwds:
+                    lst = kwds[key]
+                    if not isinstance(lst, (list, tuple)):
+                        raise TypeError("keyword '%s' should be a list or tuple"
+                                        % (key,))
+                    lst = [os.path.join(dirname, fn) for fn in lst]
+                    kwds[key] = lst
+        return kwds
+
+    # ----------
+
+    def _locate_module(self):
+        if not os.path.isfile(self.modulefilename):
+            if self.ext_package:
+                try:
+                    pkg = __import__(self.ext_package, None, None, ['__doc__'])
+                except ImportError:
+                    return      # cannot import the package itself, give up
+                    # (e.g. it might be called differently before installation)
+                path = pkg.__path__
+            else:
+                path = None
+            filename = self._vengine.find_module(self.get_module_name(), path,
+                                                 _get_so_suffixes())
+            if filename is None:
+                return
+            self.modulefilename = filename
+        self._vengine.collect_types()
+        self._has_module = True
+
+    def _write_source_to(self, file):
+        self._vengine._f = file
+        try:
+            self._vengine.write_source_to_f()
+        finally:
+            del self._vengine._f
+
+    def _write_source(self, file=None):
+        if file is not None:
+            self._write_source_to(file)
+        else:
+            # Write our source file to an in memory file.
+            f = NativeIO()
+            self._write_source_to(f)
+            source_data = f.getvalue()
+
+            # Determine if this matches the current file
+            if os.path.exists(self.sourcefilename):
+                with open(self.sourcefilename, "r") as fp:
+                    needs_written = not (fp.read() == source_data)
+            else:
+                needs_written = True
+
+            # Actually write the file out if it doesn't match
+            if needs_written:
+                _ensure_dir(self.sourcefilename)
+                with open(self.sourcefilename, "w") as fp:
+                    fp.write(source_data)
+
+            # Set this flag
+            self._has_source = True
+
+    def _compile_module(self):
+        # compile this C source
+        tmpdir = os.path.dirname(self.sourcefilename)
+        outputfilename = ffiplatform.compile(tmpdir, self.get_extension())
+        try:
+            same = ffiplatform.samefile(outputfilename, self.modulefilename)
+        except OSError:
+            same = False
+        if not same:
+            _ensure_dir(self.modulefilename)
+            shutil.move(outputfilename, self.modulefilename)
+        self._has_module = True
+
+    def _load_library(self):
+        assert self._has_module
+        if self.flags is not None:
+            return self._vengine.load_library(self.flags)
+        else:
+            return self._vengine.load_library()
+
+# ____________________________________________________________
+
+_FORCE_GENERIC_ENGINE = False      # for tests
+
+def _locate_engine_class(ffi, force_generic_engine):
+    if _FORCE_GENERIC_ENGINE:
+        force_generic_engine = True
+    if not force_generic_engine:
+        if '__pypy__' in sys.builtin_module_names:
+            force_generic_engine = True
+        else:
+            try:
+                import _cffi_backend
+            except ImportError:
+                _cffi_backend = '?'
+            if ffi._backend is not _cffi_backend:
+                force_generic_engine = True
+    if force_generic_engine:
+        from . import vengine_gen
+        return vengine_gen.VGenericEngine
+    else:
+        from . import vengine_cpy
+        return vengine_cpy.VCPythonEngine
+
+# ____________________________________________________________
+
+_TMPDIR = None
+
+def _caller_dir_pycache():
+    if _TMPDIR:
+        return _TMPDIR
+    result = os.environ.get('CFFI_TMPDIR')
+    if result:
+        return result
+    filename = sys._getframe(2).f_code.co_filename
+    return os.path.abspath(os.path.join(os.path.dirname(filename),
+                           '__pycache__'))
+
+def set_tmpdir(dirname):
+    """Set the temporary directory to use instead of __pycache__."""
+    global _TMPDIR
+    _TMPDIR = dirname
+
+def cleanup_tmpdir(tmpdir=None, keep_so=False):
+    """Clean up the temporary directory by removing all files in it
+    called `_cffi_*.{c,so}` as well as the `build` subdirectory."""
+    tmpdir = tmpdir or _caller_dir_pycache()
+    try:
+        filelist = os.listdir(tmpdir)
+    except OSError:
+        return
+    if keep_so:
+        suffix = '.c'   # only remove .c files
+    else:
+        suffix = _get_so_suffixes()[0].lower()
+    for fn in filelist:
+        if fn.lower().startswith('_cffi_') and (
+                fn.lower().endswith(suffix) or fn.lower().endswith('.c')):
+            try:
+                os.unlink(os.path.join(tmpdir, fn))
+            except OSError:
+                pass
+    clean_dir = [os.path.join(tmpdir, 'build')]
+    for dir in clean_dir:
+        try:
+            for fn in os.listdir(dir):
+                fn = os.path.join(dir, fn)
+                if os.path.isdir(fn):
+                    clean_dir.append(fn)
+                else:
+                    os.unlink(fn)
+        except OSError:
+            pass
+
+def _get_so_suffixes():
+    suffixes = _extension_suffixes()
+    if not suffixes:
+        # bah, no C_EXTENSION available.  Occurs on pypy without cpyext
+        if sys.platform == 'win32':
+            suffixes = [".pyd"]
+        else:
+            suffixes = [".so"]
+
+    return suffixes
+
+def _ensure_dir(filename):
+    dirname = os.path.dirname(filename)
+    if dirname and not os.path.isdir(dirname):
+        os.makedirs(dirname)

venv/Lib/site-packages/cryptography/exceptions.py

@@ -0,0 +1,68 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+
+import typing
+
+from cryptography import utils
+
+if typing.TYPE_CHECKING:
+    from cryptography.hazmat.bindings.openssl.binding import (
+        _OpenSSLErrorWithText,
+    )
+
+
+class _Reasons(utils.Enum):
+    BACKEND_MISSING_INTERFACE = 0
+    UNSUPPORTED_HASH = 1
+    UNSUPPORTED_CIPHER = 2
+    UNSUPPORTED_PADDING = 3
+    UNSUPPORTED_MGF = 4
+    UNSUPPORTED_PUBLIC_KEY_ALGORITHM = 5
+    UNSUPPORTED_ELLIPTIC_CURVE = 6
+    UNSUPPORTED_SERIALIZATION = 7
+    UNSUPPORTED_X509 = 8
+    UNSUPPORTED_EXCHANGE_ALGORITHM = 9
+    UNSUPPORTED_DIFFIE_HELLMAN = 10
+    UNSUPPORTED_MAC = 11
+
+
+class UnsupportedAlgorithm(Exception):
+    def __init__(
+        self, message: str, reason: typing.Optional[_Reasons] = None
+    ) -> None:
+        super(UnsupportedAlgorithm, self).__init__(message)
+        self._reason = reason
+
+
+class AlreadyFinalized(Exception):
+    pass
+
+
+class AlreadyUpdated(Exception):
+    pass
+
+
+class NotYetFinalized(Exception):
+    pass
+
+
+class InvalidTag(Exception):
+    pass
+
+
+class InvalidSignature(Exception):
+    pass
+
+
+class InternalError(Exception):
+    def __init__(
+        self, msg: str, err_code: typing.List["_OpenSSLErrorWithText"]
+    ) -> None:
+        super(InternalError, self).__init__(msg)
+        self.err_code = err_code
+
+
+class InvalidKey(Exception):
+    pass

venv/Lib/site-packages/cryptography/fernet.py

@@ -0,0 +1,212 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+
+import base64
+import binascii
+import os
+import time
+import typing
+
+from cryptography import utils
+from cryptography.exceptions import InvalidSignature
+from cryptography.hazmat.primitives import hashes, padding
+from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
+from cryptography.hazmat.primitives.hmac import HMAC
+
+
+class InvalidToken(Exception):
+    pass
+
+
+_MAX_CLOCK_SKEW = 60
+
+
+class Fernet:
+    def __init__(
+        self,
+        key: typing.Union[bytes, str],
+        backend: typing.Any = None,
+    ):
+        try:
+            key = base64.urlsafe_b64decode(key)
+        except binascii.Error as exc:
+            raise ValueError(
+                "Fernet key must be 32 url-safe base64-encoded bytes."
+            ) from exc
+        if len(key) != 32:
+            raise ValueError(
+                "Fernet key must be 32 url-safe base64-encoded bytes."
+            )
+
+        self._signing_key = key[:16]
+        self._encryption_key = key[16:]
+
+    @classmethod
+    def generate_key(cls) -> bytes:
+        return base64.urlsafe_b64encode(os.urandom(32))
+
+    def encrypt(self, data: bytes) -> bytes:
+        return self.encrypt_at_time(data, int(time.time()))
+
+    def encrypt_at_time(self, data: bytes, current_time: int) -> bytes:
+        iv = os.urandom(16)
+        return self._encrypt_from_parts(data, current_time, iv)
+
+    def _encrypt_from_parts(
+        self, data: bytes, current_time: int, iv: bytes
+    ) -> bytes:
+        utils._check_bytes("data", data)
+
+        padder = padding.PKCS7(algorithms.AES.block_size).padder()
+        padded_data = padder.update(data) + padder.finalize()
+        encryptor = Cipher(
+            algorithms.AES(self._encryption_key),
+            modes.CBC(iv),
+        ).encryptor()
+        ciphertext = encryptor.update(padded_data) + encryptor.finalize()
+
+        basic_parts = (
+            b"\x80"
+            + current_time.to_bytes(length=8, byteorder="big")
+            + iv
+            + ciphertext
+        )
+
+        h = HMAC(self._signing_key, hashes.SHA256())
+        h.update(basic_parts)
+        hmac = h.finalize()
+        return base64.urlsafe_b64encode(basic_parts + hmac)
+
+    def decrypt(self, token: bytes, ttl: typing.Optional[int] = None) -> bytes:
+        timestamp, data = Fernet._get_unverified_token_data(token)
+        if ttl is None:
+            time_info = None
+        else:
+            time_info = (ttl, int(time.time()))
+        return self._decrypt_data(data, timestamp, time_info)
+
+    def decrypt_at_time(
+        self, token: bytes, ttl: int, current_time: int
+    ) -> bytes:
+        if ttl is None:
+            raise ValueError(
+                "decrypt_at_time() can only be used with a non-None ttl"
+            )
+        timestamp, data = Fernet._get_unverified_token_data(token)
+        return self._decrypt_data(data, timestamp, (ttl, current_time))
+
+    def extract_timestamp(self, token: bytes) -> int:
+        timestamp, data = Fernet._get_unverified_token_data(token)
+        # Verify the token was not tampered with.
+        self._verify_signature(data)
+        return timestamp
+
+    @staticmethod
+    def _get_unverified_token_data(token: bytes) -> typing.Tuple[int, bytes]:
+        utils._check_bytes("token", token)
+        try:
+            data = base64.urlsafe_b64decode(token)
+        except (TypeError, binascii.Error):
+            raise InvalidToken
+
+        if not data or data[0] != 0x80:
+            raise InvalidToken
+
+        if len(data) < 9:
+            raise InvalidToken
+
+        timestamp = int.from_bytes(data[1:9], byteorder="big")
+        return timestamp, data
+
+    def _verify_signature(self, data: bytes) -> None:
+        h = HMAC(self._signing_key, hashes.SHA256())
+        h.update(data[:-32])
+        try:
+            h.verify(data[-32:])
+        except InvalidSignature:
+            raise InvalidToken
+
+    def _decrypt_data(
+        self,
+        data: bytes,
+        timestamp: int,
+        time_info: typing.Optional[typing.Tuple[int, int]],
+    ) -> bytes:
+        if time_info is not None:
+            ttl, current_time = time_info
+            if timestamp + ttl < current_time:
+                raise InvalidToken
+
+            if current_time + _MAX_CLOCK_SKEW < timestamp:
+                raise InvalidToken
+
+        self._verify_signature(data)
+
+        iv = data[9:25]
+        ciphertext = data[25:-32]
+        decryptor = Cipher(
+            algorithms.AES(self._encryption_key), modes.CBC(iv)
+        ).decryptor()
+        plaintext_padded = decryptor.update(ciphertext)
+        try:
+            plaintext_padded += decryptor.finalize()
+        except ValueError:
+            raise InvalidToken
+        unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
+
+        unpadded = unpadder.update(plaintext_padded)
+        try:
+            unpadded += unpadder.finalize()
+        except ValueError:
+            raise InvalidToken
+        return unpadded
+
+
+class MultiFernet:
+    def __init__(self, fernets: typing.Iterable[Fernet]):
+        fernets = list(fernets)
+        if not fernets:
+            raise ValueError(
+                "MultiFernet requires at least one Fernet instance"
+            )
+        self._fernets = fernets
+
+    def encrypt(self, msg: bytes) -> bytes:
+        return self.encrypt_at_time(msg, int(time.time()))
+
+    def encrypt_at_time(self, msg: bytes, current_time: int) -> bytes:
+        return self._fernets[0].encrypt_at_time(msg, current_time)
+
+    def rotate(self, msg: bytes) -> bytes:
+        timestamp, data = Fernet._get_unverified_token_data(msg)
+        for f in self._fernets:
+            try:
+                p = f._decrypt_data(data, timestamp, None)
+                break
+            except InvalidToken:
+                pass
+        else:
+            raise InvalidToken
+
+        iv = os.urandom(16)
+        return self._fernets[0]._encrypt_from_parts(p, timestamp, iv)
+
+    def decrypt(self, msg: bytes, ttl: typing.Optional[int] = None) -> bytes:
+        for f in self._fernets:
+            try:
+                return f.decrypt(msg, ttl)
+            except InvalidToken:
+                pass
+        raise InvalidToken
+
+    def decrypt_at_time(
+        self, msg: bytes, ttl: int, current_time: int
+    ) -> bytes:
+        for f in self._fernets:
+            try:
+                return f.decrypt_at_time(msg, ttl, current_time)
+            except InvalidToken:
+                pass
+        raise InvalidToken