fix handling of multiline HTTP headers in pywsgi

this is issue https://github.com/SiteSupport/gevent/issues/116

the mimetools Message class isn't of much help here, but replacing it
probably will do more harm than good. so, we parse multiline headers
on our own.

The
,----
| if 'bytearray' in __builtins__.__dict__:
`----
fails when running under py.test, so I replaced that too.

gevent/pywsgi.py

@@ -523,6 +523,23 @@ class WSGIHandler(object):
             self.start_response(_INTERNAL_ERROR_STATUS, _INTERNAL_ERROR_HEADERS)
             self.write(_INTERNAL_ERROR_BODY)
 
+    def _headers(self):
+        key = None
+        value = None
+        for header in self.headers.headers:
+            if key is not None and header[:1] in " \t":
+                value += header
+                continue
+
+            if key not in (None, 'CONTENT_TYPE', 'CONTENT_LENGTH'):
+                yield 'HTTP_' + key, value.strip()
+
+            key, value = header.split(':', 1)
+            key = key.replace('-', '_').upper()
+
+        if key not in (None, 'CONTENT_TYPE', 'CONTENT_LENGTH'):
+            yield 'HTTP_' + key, value.strip()
+
     def get_environ(self):
         env = self.server.get_environ()
         env['REQUEST_METHOD'] = self.command
@@ -548,19 +565,14 @@ class WSGIHandler(object):
             env['REMOTE_ADDR'] = str(client_address[0])
             env['REMOTE_PORT'] = str(client_address[1])
 
-        for header in self.headers.headers:
-            key, value = header.split(':', 1)
-            key = key.replace('-', '_').upper()
-            if key not in ('CONTENT_TYPE', 'CONTENT_LENGTH'):
-                value = value.strip()
-                key = 'HTTP_' + key
-                if key in env:
-                    if 'COOKIE' in key:
-                        env[key] += '; ' + value
-                    else:
-                        env[key] += ',' + value
+        for key, value in self._headers():
+            if key in env:
+                if 'COOKIE' in key:
+                    env[key] += '; ' + value
                 else:
-                    env[key] = value
+                    env[key] += ',' + value
+            else:
+                env[key] = value
 
         if env.get('HTTP_EXPECT') == '100-continue':
             socket = self.socket

greentest/test__pywsgi.py

@@ -371,7 +371,7 @@ class TestYield(CommonTests):
             yield "not found"
 
 
-if 'bytearray' in __builtins__.__dict__:
+if sys.version_info[:2] >= (2, 6):
 
     class TestBytearray(CommonTests):
 
@@ -388,6 +388,27 @@ if 'bytearray' in __builtins__.__dict__:
                 return [bytearray("not found")]
 
 
+class MultiLineHeader(TestCase):
+    @staticmethod
+    def application(env, start_response):
+        assert "test.submit" in env["CONTENT_TYPE"]
+        start_response('200 OK', [('Content-Type', 'text/plain')])
+        return ["ok"]
+
+    def test_multiline_116(self):
+        """https://github.com/SiteSupport/gevent/issues/116"""
+        request = '\r\n'.join((
+            'POST / HTTP/1.0',
+            'Host: localhost',
+            'Content-Type: multipart/related; boundary="====XXXX====";',
+            ' type="text/xml";start="test.submit"',
+            'Content-Length: 0',
+            '', ''))
+        fd = self.makefile()
+        fd.write(request)
+        read_http(fd, version='1.0')
+
+
 class TestGetArg(TestCase):
 
     @staticmethod