Fixes for two separate HTTP/1.1 bugs: 100 responses and HTTPS connections.

The HTTPResponse class now handles 100 continue responses, instead of
choking on them.  It detects them internally in the _begin() method
and ignores them.  Based on a patch by Bob Kline.

This closes SF bugs 498149 and 551273.

The FakeSocket class (for SSL) is now usable with HTTP/1.1
connections.  The old version of the code could not work with
persistent connections, because the makefile() implementation read
until EOF before returning.  If the connection is persistent, the
server sends a response and leaves the connection open.  A client that
reads until EOF will block until the server gives up on the connection
-- more than a minute in my test case.

The problem was fixed by implementing a reasonable makefile().  It
reads data only when it is needed by the layers above it.  It's
implementation uses an internal buffer with a default size of 8192.

Also, rename begin() method of HTTPResponse to _begin() because it
should only be called by the HTTPConnection.

1 files changed, 102 insertions, 32 deletions

diff --git a/Lib/httplib.py b/Lib/httplib.py
index 7e308a5..c1c4fe1 100644
--- a/Lib/httplib.py
+++ b/Lib/httplib.py
@@ -111,11 +111,7 @@ class HTTPResponse:
         self.length = _UNKNOWN          # number of bytes left in response
         self.will_close = _UNKNOWN      # conn will close at end of response
 
-    def begin(self):
-        if self.msg is not None:
-            # we've already started reading the response
-            return
-
+    def _read_status(self):
         line = self.fp.readline()
         if self.debuglevel > 0:
             print "reply:", repr(line)
@@ -135,13 +131,33 @@ class HTTPResponse:
 
         # The status code is a three-digit number
         try:
-            self.status = status = int(status)
+            status = int(status)
             if status < 100 or status > 999:
                 raise BadStatusLine(line)
         except ValueError:
             raise BadStatusLine(line)
-        self.reason = reason.strip()
+        return version, status, reason
+
+    def _begin(self):
+        if self.msg is not None:
+            # we've already started reading the response
+            return
 
+        # read until we get a non-100 response
+        while 1:
+            version, status, reason = self._read_status()
+            if status != 100:
+                break
+            # skip the header from the 100 response
+            while 1:
+                skip = self.fp.readline().strip()
+                if not skip:
+                    break
+                if self.debuglevel > 0:
+                    print "header:", skip
+            
+        self.status = status
+        self.reason = reason.strip()
         if version == 'HTTP/1.0':
             self.version = 10
         elif version.startswith('HTTP/1.'):
@@ -152,6 +168,7 @@ class HTTPResponse:
             raise UnknownProtocol(version)
 
         if self.version == 9:
+            self.chunked = 0
             self.msg = mimetools.Message(StringIO())
             return
 
@@ -233,6 +250,7 @@ class HTTPResponse:
             return ''
 
         if self.chunked:
+            assert self.chunked != _UNKNOWN
             chunk_left = self.chunk_left
             value = ''
             while 1:
@@ -363,7 +381,8 @@ class HTTPConnection:
     def connect(self):
         """Connect to the host and port specified in __init__."""
         msg = "getaddrinfo returns an empty list"
-        for res in socket.getaddrinfo(self.host, self.port, 0, socket.SOCK_STREAM):
+        for res in socket.getaddrinfo(self.host, self.port, 0,
+                                      socket.SOCK_STREAM):
             af, socktype, proto, canonname, sa = res
             try:
                 self.sock = socket.socket(af, socktype, proto)
@@ -595,7 +614,8 @@ class HTTPConnection:
         else:
             response = self.response_class(self.sock)
 
-        response.begin()
+        response._begin()
+        assert response.will_close != _UNKNOWN
         self.__state = _CS_IDLE
 
         if response.will_close:
@@ -607,28 +627,23 @@ class HTTPConnection:
 
         return response
 
+class SSLFile:
+    """File-like object wrapping an SSL socket."""
 
-class FakeSocket:
-    def __init__(self, sock, ssl):
-        self.__sock = sock
-        self.__ssl = ssl
-
-    def makefile(self, mode, bufsize=None):
-        """Return a readable file-like object with data from socket.
-
-        This method offers only partial support for the makefile
-        interface of a real socket.  It only supports modes 'r' and
-        'rb' and the bufsize argument is ignored.
-
-        The returned object contains *all* of the file data
-        """
-        if mode != 'r' and mode != 'rb':
-            raise UnimplementedFileMode()
+    BUFSIZE = 8192
+    
+    def __init__(self, sock, ssl, bufsize=None):
+        self._sock = sock
+        self._ssl = ssl
+        self._buf = ''
+        self._bufsize = bufsize or self.__class__.BUFSIZE
 
-        msgbuf = []
+    def _read(self):
+        buf = ''
+        # put in a loop so that we retry on transient errors
         while 1:
             try:
-                buf = self.__ssl.read()
+                buf = self._ssl.read(self._bufsize)
             except socket.sslerror, err:
                 if (err[0] == socket.SSL_ERROR_WANT_READ
                     or err[0] == socket.SSL_ERROR_WANT_WRITE):
@@ -640,11 +655,65 @@ class FakeSocket:
             except socket.error, err:
                 if err[0] == errno.EINTR:
                     continue
+                if err[0] == errno.EBADF:
+                    # XXX socket was closed?
+                    break
                 raise
-            if buf == '':
+            else:
+                break
+        return buf
+
+    def read(self, size=None):
+        L = [self._buf]
+        avail = len(self._buf)
+        while size is None or avail < size:
+            s = self._read()
+            if s == '':
+                break
+            L.append(s)
+            avail += len(s)
+        all = "".join(L)
+        if size is None:
+            self._buf = ''
+            return all
+        else:
+            self._buf = all[size:]
+            return all[:size]
+
+    def readline(self):
+        L = [self._buf]
+        self._buf = ''
+        while 1:
+            i = L[-1].find("\n")
+            if i >= 0:
+                break
+            s = self._read()
+            if s == '':
                 break
-            msgbuf.append(buf)
-        return StringIO("".join(msgbuf))
+            L.append(s)
+        if i == -1:
+            # loop exited because there is no more data
+            return "".join(L)
+        else:
+            all = "".join(L)
+            # XXX could do enough bookkeeping not to do a 2nd search
+            i = all.find("\n") + 1
+            line = all[:i]
+            self._buf = all[i:]
+            return line
+
+    def close(self):
+        self._sock.close()
+
+class FakeSocket:
+    def __init__(self, sock, ssl):
+        self.__sock = sock
+        self.__ssl = ssl
+
+    def makefile(self, mode, bufsize=None):
+        if mode != 'r' and mode != 'rb':
+            raise UnimplementedFileMode()
+        return SSLFile(self.__sock, self.__ssl, bufsize)
 
     def send(self, stuff, flags = 0):
         return self.__ssl.write(stuff)
@@ -885,7 +954,7 @@ def test():
     if headers:
         for header in headers.headers: print header.strip()
     print
-    print h.getfile().read()
+    print "read", len(h.getfile().read())
 
     # minimal test that code to extract host from url works
     class HTTP11(HTTP):
@@ -906,13 +975,14 @@ def test():
         hs.putrequest('GET', selector)
         hs.endheaders()
         status, reason, headers = hs.getreply()
+        # XXX why does this give a 302 response?
         print 'status =', status
         print 'reason =', reason
         print
         if headers:
             for header in headers.headers: print header.strip()
         print
-        print hs.getfile().read()
+        print "read", len(hs.getfile().read())
 
 
 if __name__ == '__main__':