Index: cgi.py
===================================================================
--- cgi.py	(revision 50876)
+++ cgi.py	(working copy)
@@ -699,7 +699,7 @@
     def read_lines_to_eof(self):
         """Internal: read lines until EOF."""
         while 1:
-            line = self.fp.readline()
+            line = self.fp.readline(1<<16)
             if not line:
                 self.done = -1
                 break
@@ -710,12 +710,13 @@
         next = "--" + self.outerboundary
         last = next + "--"
         delim = ""
+        last_line_lfend = True
         while 1:
-            line = self.fp.readline()
+            line = self.fp.readline(1<<16)
             if not line:
                 self.done = -1
                 break
-            if line[:2] == "--":
+            if line[:2] == "--" and last_line_lfend:
                 strippedline = line.strip()
                 if strippedline == next:
                     break
@@ -726,11 +727,14 @@
             if line[-2:] == "\r\n":
                 delim = "\r\n"
                 line = line[:-2]
+                last_line_lfend = True
             elif line[-1] == "\n":
                 delim = "\n"
                 line = line[:-1]
+                last_line_lfend = True
             else:
                 delim = ""
+                last_line_lfend = False
             self.__write(odelim + line)
 
     def skip_lines(self):
@@ -739,18 +743,23 @@
             return
         next = "--" + self.outerboundary
         last = next + "--"
+        last_line_lfend = True
         while 1:
-            line = self.fp.readline()
+            line = self.fp.readline(1<<16)
             if not line:
                 self.done = -1
                 break
-            if line[:2] == "--":
+            if line[:2] == "--" and last_line_lfend:
                 strippedline = line.strip()
                 if strippedline == next:
                     break
                 if strippedline == last:
                     self.done = 1
                     break
+            if line.endswith('\n'):
+                last_line_lfend = True
+            else:
+                last_line_lfend = False
 
     def make_file(self, binary=None):
         """Overridable: return a readable & writable file.