--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/lib/python3.8/wsgiref/handlers.py	Tue Mar 18 17:55:14 2025 -0400
@@ -0,0 +1,571 @@
+"""Base classes for server/gateway implementations"""
+
+from .util import FileWrapper, guess_scheme, is_hop_by_hop
+from .headers import Headers
+
+import sys, os, time
+
+__all__ = [
+    'BaseHandler', 'SimpleHandler', 'BaseCGIHandler', 'CGIHandler',
+    'IISCGIHandler', 'read_environ'
+]
+
+# Weekday and month names for HTTP date/time formatting; always English!
+_weekdayname = ["Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"]
+_monthname = [None, # Dummy so we can use 1-based month numbers
+              "Jan", "Feb", "Mar", "Apr", "May", "Jun",
+              "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
+
+def format_date_time(timestamp):
+    year, month, day, hh, mm, ss, wd, y, z = time.gmtime(timestamp)
+    return "%s, %02d %3s %4d %02d:%02d:%02d GMT" % (
+        _weekdayname[wd], day, _monthname[month], year, hh, mm, ss
+    )
+
+_is_request = {
+    'SCRIPT_NAME', 'PATH_INFO', 'QUERY_STRING', 'REQUEST_METHOD', 'AUTH_TYPE',
+    'CONTENT_TYPE', 'CONTENT_LENGTH', 'HTTPS', 'REMOTE_USER', 'REMOTE_IDENT',
+}.__contains__
+
+def _needs_transcode(k):
+    return _is_request(k) or k.startswith('HTTP_') or k.startswith('SSL_') \
+        or (k.startswith('REDIRECT_') and _needs_transcode(k[9:]))
+
+def read_environ():
+    """Read environment, fixing HTTP variables"""
+    enc = sys.getfilesystemencoding()
+    esc = 'surrogateescape'
+    try:
+        ''.encode('utf-8', esc)
+    except LookupError:
+        esc = 'replace'
+    environ = {}
+
+    # Take the basic environment from native-unicode os.environ. Attempt to
+    # fix up the variables that come from the HTTP request to compensate for
+    # the bytes->unicode decoding step that will already have taken place.
+    for k, v in os.environ.items():
+        if _needs_transcode(k):
+
+            # On win32, the os.environ is natively Unicode. Different servers
+            # decode the request bytes using different encodings.
+            if sys.platform == 'win32':
+                software = os.environ.get('SERVER_SOFTWARE', '').lower()
+
+                # On IIS, the HTTP request will be decoded as UTF-8 as long
+                # as the input is a valid UTF-8 sequence. Otherwise it is
+                # decoded using the system code page (mbcs), with no way to
+                # detect this has happened. Because UTF-8 is the more likely
+                # encoding, and mbcs is inherently unreliable (an mbcs string
+                # that happens to be valid UTF-8 will not be decoded as mbcs)
+                # always recreate the original bytes as UTF-8.
+                if software.startswith('microsoft-iis/'):
+                    v = v.encode('utf-8').decode('iso-8859-1')
+
+                # Apache mod_cgi writes bytes-as-unicode (as if ISO-8859-1) direct
+                # to the Unicode environ. No modification needed.
+                elif software.startswith('apache/'):
+                    pass
+
+                # Python 3's http.server.CGIHTTPRequestHandler decodes
+                # using the urllib.unquote default of UTF-8, amongst other
+                # issues.
+                elif (
+                    software.startswith('simplehttp/')
+                    and 'python/3' in software
+                ):
+                    v = v.encode('utf-8').decode('iso-8859-1')
+
+                # For other servers, guess that they have written bytes to
+                # the environ using stdio byte-oriented interfaces, ending up
+                # with the system code page.
+                else:
+                    v = v.encode(enc, 'replace').decode('iso-8859-1')
+
+            # Recover bytes from unicode environ, using surrogate escapes
+            # where available (Python 3.1+).
+            else:
+                v = v.encode(enc, esc).decode('iso-8859-1')
+
+        environ[k] = v
+    return environ
+
+
+class BaseHandler:
+    """Manage the invocation of a WSGI application"""
+
+    # Configuration parameters; can override per-subclass or per-instance
+    wsgi_version = (1,0)
+    wsgi_multithread = True
+    wsgi_multiprocess = True
+    wsgi_run_once = False
+
+    origin_server = True    # We are transmitting direct to client
+    http_version  = "1.0"   # Version that should be used for response
+    server_software = None  # String name of server software, if any
+
+    # os_environ is used to supply configuration from the OS environment:
+    # by default it's a copy of 'os.environ' as of import time, but you can
+    # override this in e.g. your __init__ method.
+    os_environ= read_environ()
+
+    # Collaborator classes
+    wsgi_file_wrapper = FileWrapper     # set to None to disable
+    headers_class = Headers             # must be a Headers-like class
+
+    # Error handling (also per-subclass or per-instance)
+    traceback_limit = None  # Print entire traceback to self.get_stderr()
+    error_status = "500 Internal Server Error"
+    error_headers = [('Content-Type','text/plain')]
+    error_body = b"A server error occurred.  Please contact the administrator."
+
+    # State variables (don't mess with these)
+    status = result = None
+    headers_sent = False
+    headers = None
+    bytes_sent = 0
+
+    def run(self, application):
+        """Invoke the application"""
+        # Note to self: don't move the close()!  Asynchronous servers shouldn't
+        # call close() from finish_response(), so if you close() anywhere but
+        # the double-error branch here, you'll break asynchronous servers by
+        # prematurely closing.  Async servers must return from 'run()' without
+        # closing if there might still be output to iterate over.
+        try:
+            self.setup_environ()
+            self.result = application(self.environ, self.start_response)
+            self.finish_response()
+        except (ConnectionAbortedError, BrokenPipeError, ConnectionResetError):
+            # We expect the client to close the connection abruptly from time
+            # to time.
+            return
+        except:
+            try:
+                self.handle_error()
+            except:
+                # If we get an error handling an error, just give up already!
+                self.close()
+                raise   # ...and let the actual server figure it out.
+
+
+    def setup_environ(self):
+        """Set up the environment for one request"""
+
+        env = self.environ = self.os_environ.copy()
+        self.add_cgi_vars()
+
+        env['wsgi.input']        = self.get_stdin()
+        env['wsgi.errors']       = self.get_stderr()
+        env['wsgi.version']      = self.wsgi_version
+        env['wsgi.run_once']     = self.wsgi_run_once
+        env['wsgi.url_scheme']   = self.get_scheme()
+        env['wsgi.multithread']  = self.wsgi_multithread
+        env['wsgi.multiprocess'] = self.wsgi_multiprocess
+
+        if self.wsgi_file_wrapper is not None:
+            env['wsgi.file_wrapper'] = self.wsgi_file_wrapper
+
+        if self.origin_server and self.server_software:
+            env.setdefault('SERVER_SOFTWARE',self.server_software)
+
+
+    def finish_response(self):
+        """Send any iterable data, then close self and the iterable
+
+        Subclasses intended for use in asynchronous servers will
+        want to redefine this method, such that it sets up callbacks
+        in the event loop to iterate over the data, and to call
+        'self.close()' once the response is finished.
+        """
+        try:
+            if not self.result_is_file() or not self.sendfile():
+                for data in self.result:
+                    self.write(data)
+                self.finish_content()
+        except:
+            # Call close() on the iterable returned by the WSGI application
+            # in case of an exception.
+            if hasattr(self.result, 'close'):
+                self.result.close()
+            raise
+        else:
+            # We only call close() when no exception is raised, because it
+            # will set status, result, headers, and environ fields to None.
+            # See bpo-29183 for more details.
+            self.close()
+
+
+    def get_scheme(self):
+        """Return the URL scheme being used"""
+        return guess_scheme(self.environ)
+
+
+    def set_content_length(self):
+        """Compute Content-Length or switch to chunked encoding if possible"""
+        try:
+            blocks = len(self.result)
+        except (TypeError,AttributeError,NotImplementedError):
+            pass
+        else:
+            if blocks==1:
+                self.headers['Content-Length'] = str(self.bytes_sent)
+                return
+        # XXX Try for chunked encoding if origin server and client is 1.1
+
+
+    def cleanup_headers(self):
+        """Make any necessary header changes or defaults
+
+        Subclasses can extend this to add other defaults.
+        """
+        if 'Content-Length' not in self.headers:
+            self.set_content_length()
+
+    def start_response(self, status, headers,exc_info=None):
+        """'start_response()' callable as specified by PEP 3333"""
+
+        if exc_info:
+            try:
+                if self.headers_sent:
+                    # Re-raise original exception if headers sent
+                    raise exc_info[0](exc_info[1]).with_traceback(exc_info[2])
+            finally:
+                exc_info = None        # avoid dangling circular ref
+        elif self.headers is not None:
+            raise AssertionError("Headers already set!")
+
+        self.status = status
+        self.headers = self.headers_class(headers)
+        status = self._convert_string_type(status, "Status")
+        assert len(status)>=4,"Status must be at least 4 characters"
+        assert status[:3].isdigit(), "Status message must begin w/3-digit code"
+        assert status[3]==" ", "Status message must have a space after code"
+
+        if __debug__:
+            for name, val in headers:
+                name = self._convert_string_type(name, "Header name")
+                val = self._convert_string_type(val, "Header value")
+                assert not is_hop_by_hop(name),\
+                       f"Hop-by-hop header, '{name}: {val}', not allowed"
+
+        return self.write
+
+    def _convert_string_type(self, value, title):
+        """Convert/check value type."""
+        if type(value) is str:
+            return value
+        raise AssertionError(
+            "{0} must be of type str (got {1})".format(title, repr(value))
+        )
+
+    def send_preamble(self):
+        """Transmit version/status/date/server, via self._write()"""
+        if self.origin_server:
+            if self.client_is_modern():
+                self._write(('HTTP/%s %s\r\n' % (self.http_version,self.status)).encode('iso-8859-1'))
+                if 'Date' not in self.headers:
+                    self._write(
+                        ('Date: %s\r\n' % format_date_time(time.time())).encode('iso-8859-1')
+                    )
+                if self.server_software and 'Server' not in self.headers:
+                    self._write(('Server: %s\r\n' % self.server_software).encode('iso-8859-1'))
+        else:
+            self._write(('Status: %s\r\n' % self.status).encode('iso-8859-1'))
+
+    def write(self, data):
+        """'write()' callable as specified by PEP 3333"""
+
+        assert type(data) is bytes, \
+            "write() argument must be a bytes instance"
+
+        if not self.status:
+            raise AssertionError("write() before start_response()")
+
+        elif not self.headers_sent:
+            # Before the first output, send the stored headers
+            self.bytes_sent = len(data)    # make sure we know content-length
+            self.send_headers()
+        else:
+            self.bytes_sent += len(data)
+
+        # XXX check Content-Length and truncate if too many bytes written?
+        self._write(data)
+        self._flush()
+
+
+    def sendfile(self):
+        """Platform-specific file transmission
+
+        Override this method in subclasses to support platform-specific
+        file transmission.  It is only called if the application's
+        return iterable ('self.result') is an instance of
+        'self.wsgi_file_wrapper'.
+
+        This method should return a true value if it was able to actually
+        transmit the wrapped file-like object using a platform-specific
+        approach.  It should return a false value if normal iteration
+        should be used instead.  An exception can be raised to indicate
+        that transmission was attempted, but failed.
+
+        NOTE: this method should call 'self.send_headers()' if
+        'self.headers_sent' is false and it is going to attempt direct
+        transmission of the file.
+        """
+        return False   # No platform-specific transmission by default
+
+
+    def finish_content(self):
+        """Ensure headers and content have both been sent"""
+        if not self.headers_sent:
+            # Only zero Content-Length if not set by the application (so
+            # that HEAD requests can be satisfied properly, see #3839)
+            self.headers.setdefault('Content-Length', "0")
+            self.send_headers()
+        else:
+            pass # XXX check if content-length was too short?
+
+    def close(self):
+        """Close the iterable (if needed) and reset all instance vars
+
+        Subclasses may want to also drop the client connection.
+        """
+        try:
+            if hasattr(self.result,'close'):
+                self.result.close()
+        finally:
+            self.result = self.headers = self.status = self.environ = None
+            self.bytes_sent = 0; self.headers_sent = False
+
+
+    def send_headers(self):
+        """Transmit headers to the client, via self._write()"""
+        self.cleanup_headers()
+        self.headers_sent = True
+        if not self.origin_server or self.client_is_modern():
+            self.send_preamble()
+            self._write(bytes(self.headers))
+
+
+    def result_is_file(self):
+        """True if 'self.result' is an instance of 'self.wsgi_file_wrapper'"""
+        wrapper = self.wsgi_file_wrapper
+        return wrapper is not None and isinstance(self.result,wrapper)
+
+
+    def client_is_modern(self):
+        """True if client can accept status and headers"""
+        return self.environ['SERVER_PROTOCOL'].upper() != 'HTTP/0.9'
+
+
+    def log_exception(self,exc_info):
+        """Log the 'exc_info' tuple in the server log
+
+        Subclasses may override to retarget the output or change its format.
+        """
+        try:
+            from traceback import print_exception
+            stderr = self.get_stderr()
+            print_exception(
+                exc_info[0], exc_info[1], exc_info[2],
+                self.traceback_limit, stderr
+            )
+            stderr.flush()
+        finally:
+            exc_info = None
+
+    def handle_error(self):
+        """Log current error, and send error output to client if possible"""
+        self.log_exception(sys.exc_info())
+        if not self.headers_sent:
+            self.result = self.error_output(self.environ, self.start_response)
+            self.finish_response()
+        # XXX else: attempt advanced recovery techniques for HTML or text?
+
+    def error_output(self, environ, start_response):
+        """WSGI mini-app to create error output
+
+        By default, this just uses the 'error_status', 'error_headers',
+        and 'error_body' attributes to generate an output page.  It can
+        be overridden in a subclass to dynamically generate diagnostics,
+        choose an appropriate message for the user's preferred language, etc.
+
+        Note, however, that it's not recommended from a security perspective to
+        spit out diagnostics to any old user; ideally, you should have to do
+        something special to enable diagnostic output, which is why we don't
+        include any here!
+        """
+        start_response(self.error_status,self.error_headers[:],sys.exc_info())
+        return [self.error_body]
+
+
+    # Pure abstract methods; *must* be overridden in subclasses
+
+    def _write(self,data):
+        """Override in subclass to buffer data for send to client
+
+        It's okay if this method actually transmits the data; BaseHandler
+        just separates write and flush operations for greater efficiency
+        when the underlying system actually has such a distinction.
+        """
+        raise NotImplementedError
+
+    def _flush(self):
+        """Override in subclass to force sending of recent '_write()' calls
+
+        It's okay if this method is a no-op (i.e., if '_write()' actually
+        sends the data.
+        """
+        raise NotImplementedError
+
+    def get_stdin(self):
+        """Override in subclass to return suitable 'wsgi.input'"""
+        raise NotImplementedError
+
+    def get_stderr(self):
+        """Override in subclass to return suitable 'wsgi.errors'"""
+        raise NotImplementedError
+
+    def add_cgi_vars(self):
+        """Override in subclass to insert CGI variables in 'self.environ'"""
+        raise NotImplementedError
+
+
+class SimpleHandler(BaseHandler):
+    """Handler that's just initialized with streams, environment, etc.
+
+    This handler subclass is intended for synchronous HTTP/1.0 origin servers,
+    and handles sending the entire response output, given the correct inputs.
+
+    Usage::
+
+        handler = SimpleHandler(
+            inp,out,err,env, multithread=False, multiprocess=True
+        )
+        handler.run(app)"""
+
+    def __init__(self,stdin,stdout,stderr,environ,
+        multithread=True, multiprocess=False
+    ):
+        self.stdin = stdin
+        self.stdout = stdout
+        self.stderr = stderr
+        self.base_env = environ
+        self.wsgi_multithread = multithread
+        self.wsgi_multiprocess = multiprocess
+
+    def get_stdin(self):
+        return self.stdin
+
+    def get_stderr(self):
+        return self.stderr
+
+    def add_cgi_vars(self):
+        self.environ.update(self.base_env)
+
+    def _write(self,data):
+        result = self.stdout.write(data)
+        if result is None or result == len(data):
+            return
+        from warnings import warn
+        warn("SimpleHandler.stdout.write() should not do partial writes",
+            DeprecationWarning)
+        while True:
+            data = data[result:]
+            if not data:
+                break
+            result = self.stdout.write(data)
+
+    def _flush(self):
+        self.stdout.flush()
+        self._flush = self.stdout.flush
+
+
+class BaseCGIHandler(SimpleHandler):
+
+    """CGI-like systems using input/output/error streams and environ mapping
+
+    Usage::
+
+        handler = BaseCGIHandler(inp,out,err,env)
+        handler.run(app)
+
+    This handler class is useful for gateway protocols like ReadyExec and
+    FastCGI, that have usable input/output/error streams and an environment
+    mapping.  It's also the base class for CGIHandler, which just uses
+    sys.stdin, os.environ, and so on.
+
+    The constructor also takes keyword arguments 'multithread' and
+    'multiprocess' (defaulting to 'True' and 'False' respectively) to control
+    the configuration sent to the application.  It sets 'origin_server' to
+    False (to enable CGI-like output), and assumes that 'wsgi.run_once' is
+    False.
+    """
+
+    origin_server = False
+
+
+class CGIHandler(BaseCGIHandler):
+
+    """CGI-based invocation via sys.stdin/stdout/stderr and os.environ
+
+    Usage::
+
+        CGIHandler().run(app)
+
+    The difference between this class and BaseCGIHandler is that it always
+    uses 'wsgi.run_once' of 'True', 'wsgi.multithread' of 'False', and
+    'wsgi.multiprocess' of 'True'.  It does not take any initialization
+    parameters, but always uses 'sys.stdin', 'os.environ', and friends.
+
+    If you need to override any of these parameters, use BaseCGIHandler
+    instead.
+    """
+
+    wsgi_run_once = True
+    # Do not allow os.environ to leak between requests in Google App Engine
+    # and other multi-run CGI use cases.  This is not easily testable.
+    # See http://bugs.python.org/issue7250
+    os_environ = {}
+
+    def __init__(self):
+        BaseCGIHandler.__init__(
+            self, sys.stdin.buffer, sys.stdout.buffer, sys.stderr,
+            read_environ(), multithread=False, multiprocess=True
+        )
+
+
+class IISCGIHandler(BaseCGIHandler):
+    """CGI-based invocation with workaround for IIS path bug
+
+    This handler should be used in preference to CGIHandler when deploying on
+    Microsoft IIS without having set the config allowPathInfo option (IIS>=7)
+    or metabase allowPathInfoForScriptMappings (IIS<7).
+    """
+    wsgi_run_once = True
+    os_environ = {}
+
+    # By default, IIS gives a PATH_INFO that duplicates the SCRIPT_NAME at
+    # the front, causing problems for WSGI applications that wish to implement
+    # routing. This handler strips any such duplicated path.
+
+    # IIS can be configured to pass the correct PATH_INFO, but this causes
+    # another bug where PATH_TRANSLATED is wrong. Luckily this variable is
+    # rarely used and is not guaranteed by WSGI. On IIS<7, though, the
+    # setting can only be made on a vhost level, affecting all other script
+    # mappings, many of which break when exposed to the PATH_TRANSLATED bug.
+    # For this reason IIS<7 is almost never deployed with the fix. (Even IIS7
+    # rarely uses it because there is still no UI for it.)
+
+    # There is no way for CGI code to tell whether the option was set, so a
+    # separate handler class is provided.
+    def __init__(self):
+        environ= read_environ()
+        path = environ.get('PATH_INFO', '')
+        script = environ.get('SCRIPT_NAME', '')
+        if (path+'/').startswith(script+'/'):
+            environ['PATH_INFO'] = path[len(script):]
+        BaseCGIHandler.__init__(
+            self, sys.stdin.buffer, sys.stdout.buffer, sys.stderr,
+            environ, multithread=False, multiprocess=True
+        )