Fix for issue 6851: urllib.urlopen crashes in a thread on OSX 10.6

4 files changed, 262 insertions, 183 deletions

diff --git a/Lib/urllib.py b/Lib/urllib.py
index a56f162..51e8df9 100644
--- a/Lib/urllib.py
+++ b/Lib/urllib.py
@@ -1327,38 +1327,7 @@ def proxy_bypass_environment(host):
 
 
 if sys.platform == 'darwin':
-
-    def _CFSetup(sc):
-        from ctypes import c_int32, c_void_p, c_char_p, c_int
-        sc.CFStringCreateWithCString.argtypes = [ c_void_p, c_char_p, c_int32 ]
-        sc.CFStringCreateWithCString.restype = c_void_p
-        sc.SCDynamicStoreCopyProxies.argtypes = [ c_void_p ]
-        sc.SCDynamicStoreCopyProxies.restype = c_void_p
-        sc.CFDictionaryGetValue.argtypes = [ c_void_p, c_void_p ]
-        sc.CFDictionaryGetValue.restype = c_void_p
-        sc.CFStringGetLength.argtypes = [ c_void_p ]
-        sc.CFStringGetLength.restype = c_int32
-        sc.CFStringGetCString.argtypes = [ c_void_p, c_char_p, c_int32, c_int32 ]
-        sc.CFStringGetCString.restype = c_int32
-        sc.CFNumberGetValue.argtypes = [ c_void_p, c_int, c_void_p ]
-        sc.CFNumberGetValue.restype = c_int32
-        sc.CFRelease.argtypes = [ c_void_p ]
-        sc.CFRelease.restype = None
-
-    def _CStringFromCFString(sc, value):
-        from ctypes import create_string_buffer
-        length = sc.CFStringGetLength(value) + 1
-        buff = create_string_buffer(length)
-        sc.CFStringGetCString(value, buff, length, 0)
-        return buff.value
-
-    def _CFNumberToInt32(sc, cfnum):
-        from ctypes import byref, c_int
-        val = c_int()
-        kCFNumberSInt32Type = 3
-        sc.CFNumberGetValue(cfnum, kCFNumberSInt32Type, byref(val))
-        return val.value
-
+    from _scproxy import _get_proxy_settings, _get_proxies
 
     def proxy_bypass_macosx_sysconf(host):
         """
@@ -1367,8 +1336,6 @@ if sys.platform == 'darwin':
         This function uses the MacOSX framework SystemConfiguration
         to fetch the proxy information.
         """
-        from ctypes import cdll
-        from ctypes.util import find_library
         import re
         import socket
         from fnmatch import fnmatch
@@ -1380,63 +1347,35 @@ if sys.platform == 'darwin':
                 parts = (parts + [0, 0, 0, 0])[:4]
             return (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8) | parts[3]
 
-        sc = cdll.LoadLibrary(find_library("SystemConfiguration"))
-        _CFSetup(sc)
+        proxy_settings = _get_proxy_settings()
 
-        hostIP = None
+        # Check for simple host names:
+        if '.' not in host:
+            if proxy_settings['exclude_simple']:
+                return True
 
-        if not sc:
-            return False
+        for value in proxy_settings.get('exceptions'):
+            # Items in the list are strings like these: *.local, 169.254/16
+            value = sc.CFArrayGetValueAtIndex(exceptions, index)
+            if not value: continue
 
-        kSCPropNetProxiesExceptionsList = sc.CFStringCreateWithCString(0, "ExceptionsList", 0)
-        kSCPropNetProxiesExcludeSimpleHostnames = sc.CFStringCreateWithCString(0,
-                "ExcludeSimpleHostnames", 0)
+            m = re.match(r"(\d+(?:\.\d+)*)(/\d+)?", value)
+            if m is not None:
+                if hostIP is None:
+                    hostIP = socket.gethostbyname(host)
+                    hostIP = ip2num(hostIP)
 
+                base = ip2num(m.group(1))
+                mask = int(m.group(2)[1:])
+                mask = 32 - mask
 
-        proxyDict = sc.SCDynamicStoreCopyProxies(None)
-        if proxyDict is None:
-            return False
-
-        try:
-            # Check for simple host names:
-            if '.' not in host:
-                exclude_simple = sc.CFDictionaryGetValue(proxyDict,
-                        kSCPropNetProxiesExcludeSimpleHostnames)
-                if exclude_simple and _CFNumberToInt32(sc, exclude_simple):
+                if (hostIP >> mask) == (base >> mask):
                     return True
 
+            elif fnmatch(host, value):
+                return True
 
-            # Check the exceptions list:
-            exceptions = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesExceptionsList)
-            if exceptions:
-                # Items in the list are strings like these: *.local, 169.254/16
-                for index in xrange(sc.CFArrayGetCount(exceptions)):
-                    value = sc.CFArrayGetValueAtIndex(exceptions, index)
-                    if not value: continue
-                    value = _CStringFromCFString(sc, value)
-
-                    m = re.match(r"(\d+(?:\.\d+)*)(/\d+)?", value)
-                    if m is not None:
-                        if hostIP is None:
-                            hostIP = socket.gethostbyname(host)
-                            hostIP = ip2num(hostIP)
-
-                        base = ip2num(m.group(1))
-                        mask = int(m.group(2)[1:])
-                        mask = 32 - mask
-
-                        if (hostIP >> mask) == (base >> mask):
-                            return True
-
-                    elif fnmatch(host, value):
-                        return True
-
-            return False
-
-        finally:
-            sc.CFRelease(kSCPropNetProxiesExceptionsList)
-            sc.CFRelease(kSCPropNetProxiesExcludeSimpleHostnames)
-
+        return False
 
 
     def getproxies_macosx_sysconf():
@@ -1445,106 +1384,7 @@ if sys.platform == 'darwin':
         This function uses the MacOSX framework SystemConfiguration
         to fetch the proxy information.
         """
-        from ctypes import cdll
-        from ctypes.util import find_library
-
-        sc = cdll.LoadLibrary(find_library("SystemConfiguration"))
-        _CFSetup(sc)
-
-        if not sc:
-            return {}
-
-        kSCPropNetProxiesHTTPEnable = sc.CFStringCreateWithCString(0, "HTTPEnable", 0)
-        kSCPropNetProxiesHTTPProxy = sc.CFStringCreateWithCString(0, "HTTPProxy", 0)
-        kSCPropNetProxiesHTTPPort = sc.CFStringCreateWithCString(0, "HTTPPort", 0)
-
-        kSCPropNetProxiesHTTPSEnable = sc.CFStringCreateWithCString(0, "HTTPSEnable", 0)
-        kSCPropNetProxiesHTTPSProxy = sc.CFStringCreateWithCString(0, "HTTPSProxy", 0)
-        kSCPropNetProxiesHTTPSPort = sc.CFStringCreateWithCString(0, "HTTPSPort", 0)
-
-        kSCPropNetProxiesFTPEnable = sc.CFStringCreateWithCString(0, "FTPEnable", 0)
-        kSCPropNetProxiesFTPPassive = sc.CFStringCreateWithCString(0, "FTPPassive", 0)
-        kSCPropNetProxiesFTPPort = sc.CFStringCreateWithCString(0, "FTPPort", 0)
-        kSCPropNetProxiesFTPProxy = sc.CFStringCreateWithCString(0, "FTPProxy", 0)
-
-        kSCPropNetProxiesGopherEnable = sc.CFStringCreateWithCString(0, "GopherEnable", 0)
-        kSCPropNetProxiesGopherPort = sc.CFStringCreateWithCString(0, "GopherPort", 0)
-        kSCPropNetProxiesGopherProxy = sc.CFStringCreateWithCString(0, "GopherProxy", 0)
-
-        proxies = {}
-        proxyDict = sc.SCDynamicStoreCopyProxies(None)
-
-        try:
-            # HTTP:
-            enabled = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesHTTPEnable)
-            if enabled and _CFNumberToInt32(sc, enabled):
-                proxy = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesHTTPProxy)
-                port = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesHTTPPort)
-
-                if proxy:
-                    proxy = _CStringFromCFString(sc, proxy)
-                    if port:
-                        port = _CFNumberToInt32(sc, port)
-                        proxies["http"] = "http://%s:%i" % (proxy, port)
-                    else:
-                        proxies["http"] = "http://%s" % (proxy, )
-
-            # HTTPS:
-            enabled = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesHTTPSEnable)
-            if enabled and _CFNumberToInt32(sc, enabled):
-                proxy = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesHTTPSProxy)
-                port = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesHTTPSPort)
-
-                if proxy:
-                    proxy = _CStringFromCFString(sc, proxy)
-                    if port:
-                        port = _CFNumberToInt32(sc, port)
-                        proxies["https"] = "http://%s:%i" % (proxy, port)
-                    else:
-                        proxies["https"] = "http://%s" % (proxy, )
-
-            # FTP:
-            enabled = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesFTPEnable)
-            if enabled and _CFNumberToInt32(sc, enabled):
-                proxy = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesFTPProxy)
-                port = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesFTPPort)
-
-                if proxy:
-                    proxy = _CStringFromCFString(sc, proxy)
-                    if port:
-                        port = _CFNumberToInt32(sc, port)
-                        proxies["ftp"] = "http://%s:%i" % (proxy, port)
-                    else:
-                        proxies["ftp"] = "http://%s" % (proxy, )
-
-            # Gopher:
-            enabled = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesGopherEnable)
-            if enabled and _CFNumberToInt32(sc, enabled):
-                proxy = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesGopherProxy)
-                port = sc.CFDictionaryGetValue(proxyDict, kSCPropNetProxiesGopherPort)
-
-                if proxy:
-                    proxy = _CStringFromCFString(sc, proxy)
-                    if port:
-                        port = _CFNumberToInt32(sc, port)
-                        proxies["gopher"] = "http://%s:%i" % (proxy, port)
-                    else:
-                        proxies["gopher"] = "http://%s" % (proxy, )
-        finally:
-            sc.CFRelease(proxyDict)
-
-        sc.CFRelease(kSCPropNetProxiesHTTPEnable)
-        sc.CFRelease(kSCPropNetProxiesHTTPProxy)
-        sc.CFRelease(kSCPropNetProxiesHTTPPort)
-        sc.CFRelease(kSCPropNetProxiesFTPEnable)
-        sc.CFRelease(kSCPropNetProxiesFTPPassive)
-        sc.CFRelease(kSCPropNetProxiesFTPPort)
-        sc.CFRelease(kSCPropNetProxiesFTPProxy)
-        sc.CFRelease(kSCPropNetProxiesGopherEnable)
-        sc.CFRelease(kSCPropNetProxiesGopherPort)
-        sc.CFRelease(kSCPropNetProxiesGopherProxy)
-
-        return proxies
+        return _get_proxies()
 
 
 
diff --git a/Mac/Modules/_scproxy.c b/Mac/Modules/_scproxy.c
new file mode 100644
index 0000000..003f6a4
--- /dev/null
+++ b/Mac/Modules/_scproxy.c
@@ -0,0 +1,226 @@
+/*
+ * Helper method for urllib to fetch the proxy configuration settings
+ * using the SystemConfiguration framework.
+ */
+#include <Python.h>
+#include <SystemConfiguration/SystemConfiguration.h>
+
+static int32_t 
+cfnum_to_int32(CFNumberRef num)
+{
+	int32_t result;
+
+	CFNumberGetValue(num, kCFNumberSInt32Type, &result);
+	return result;
+}
+
+static PyObject*
+cfstring_to_pystring(CFStringRef ref)
+{
+	const char* s; 
+
+	s = CFStringGetCStringPtr(ref, kCFStringEncodingUTF8);
+	if (s) {
+		return PyString_FromString(s);
+
+	} else {
+		CFIndex len = CFStringGetLength(ref);
+		Boolean ok;
+		PyObject* result;
+		result = PyString_FromStringAndSize(NULL, len*4);
+
+		ok = CFStringGetCString(ref, 
+				PyString_AS_STRING(result),
+				PyString_GET_SIZE(result),
+				kCFStringEncodingUTF8);
+		if (!ok) {
+			Py_DECREF(result);
+			return NULL;
+		} else {
+			_PyString_Resize(&result, 
+				strlen(PyString_AS_STRING(result)));
+		}
+		return result;
+	}
+}
+
+
+static PyObject*
+get_proxy_settings(PyObject* mod __attribute__((__unused__)))
+{
+	CFDictionaryRef proxyDict = NULL;
+	CFNumberRef aNum = NULL;
+	CFArrayRef anArray = NULL;
+	PyObject* result = NULL;
+	PyObject* v;
+	int r;
+
+	proxyDict = SCDynamicStoreCopyProxies(NULL);
+	if (!proxyDict) {
+		Py_INCREF(Py_None);
+		return Py_None;
+	}
+
+	result = PyDict_New();
+	if (result == NULL) goto error;
+
+	aNum = CFDictionaryGetValue(proxyDict, 
+			kSCPropNetProxiesExcludeSimpleHostnames);
+	if (aNum == NULL) {
+		v = PyBool_FromLong(0);
+	} else {
+		v = PyBool_FromLong(cfnum_to_int32(aNum));
+	}
+	if (v == NULL) goto error;
+
+	r = PyDict_SetItemString(result, "exclude_simple", v);
+	Py_DECREF(v); v = NULL;
+	if (r == -1) goto error;
+
+	anArray = CFDictionaryGetValue(proxyDict, 
+			kSCPropNetProxiesExceptionsList);
+	if (anArray != NULL) {
+		CFIndex len = CFArrayGetCount(anArray);
+		CFIndex i;
+		v = PyTuple_New(len);
+		if (v == NULL) goto error;
+
+		r = PyDict_SetItemString(result, "exceptions", v);
+		Py_DECREF(v);
+		if (r == -1) goto error;
+
+		for (i = 0; i < len; i++) {
+			CFStringRef aString = NULL;
+
+			aString = CFArrayGetValueAtIndex(anArray, i);
+			if (aString == NULL) {
+				PyTuple_SetItem(v, i, Py_None);
+				Py_INCREF(Py_None);
+			} else {
+				PyObject* t = cfstring_to_pystring(aString);
+				if (!t) {
+					PyTuple_SetItem(v, i, Py_None);
+					Py_INCREF(Py_None);
+				} else {
+					PyTuple_SetItem(v, i, t);
+				}
+			}
+		}
+	}
+
+	CFRelease(proxyDict);
+	return result;
+
+error:
+	if (proxyDict)  CFRelease(proxyDict);
+	Py_XDECREF(result);
+	return NULL;
+}
+
+static int
+set_proxy(PyObject* proxies, char* proto, CFDictionaryRef proxyDict,
+		CFStringRef enabledKey, 
+		CFStringRef hostKey, CFStringRef portKey)
+{
+	CFNumberRef aNum;
+
+	aNum = CFDictionaryGetValue(proxyDict, enabledKey);
+	if (aNum && cfnum_to_int32(aNum)) {
+		CFStringRef hostString;
+
+		hostString = CFDictionaryGetValue(proxyDict, hostKey);
+		aNum = CFDictionaryGetValue(proxyDict, portKey);
+
+		if (hostString) {
+			int r;
+			PyObject* h = cfstring_to_pystring(hostString);
+			PyObject* v;
+			if (h) {
+				if (aNum) {
+					int32_t port = cfnum_to_int32(aNum);
+					v = PyString_FromFormat("http://%s:%ld",
+						PyString_AS_STRING(h),
+						(long)port);
+				} else {
+					v = PyString_FromFormat("http://%s",
+						PyString_AS_STRING(h));
+				}
+				Py_DECREF(h);
+				if (!v) return -1;
+				r = PyDict_SetItemString(proxies, proto,
+					v);
+				Py_DECREF(v);
+				return r;
+			}
+		}
+
+	}
+	return 0;
+}
+
+
+
+static PyObject*
+get_proxies(PyObject* mod __attribute__((__unused__)))
+{
+	PyObject* result = NULL;
+	int r;
+	CFDictionaryRef proxyDict = NULL;
+
+	proxyDict = SCDynamicStoreCopyProxies(NULL);
+	if (proxyDict == NULL) {
+		return PyDict_New();
+	}
+
+	result = PyDict_New();
+	if (result == NULL) goto error;
+
+	r = set_proxy(result, "http", proxyDict,
+		kSCPropNetProxiesHTTPEnable,
+		kSCPropNetProxiesHTTPProxy,
+		kSCPropNetProxiesHTTPPort);
+	if (r == -1) goto error;
+	r = set_proxy(result, "https", proxyDict,
+		kSCPropNetProxiesHTTPSEnable,
+		kSCPropNetProxiesHTTPSProxy,
+		kSCPropNetProxiesHTTPSPort);
+	if (r == -1) goto error;
+	r = set_proxy(result, "ftp", proxyDict,
+		kSCPropNetProxiesFTPEnable,
+		kSCPropNetProxiesFTPProxy,
+		kSCPropNetProxiesFTPPort);
+	if (r == -1) goto error;
+	r = set_proxy(result, "gopher", proxyDict,
+		kSCPropNetProxiesGopherEnable,
+		kSCPropNetProxiesGopherProxy,
+		kSCPropNetProxiesGopherPort);
+	if (r == -1) goto error;
+
+	CFRelease(proxyDict);
+	return result;
+error:
+	if (proxyDict)  CFRelease(proxyDict);
+	Py_XDECREF(result);
+	return NULL;
+}
+
+static PyMethodDef mod_methods[] = {
+	{
+		"_get_proxy_settings",
+		(PyCFunction)get_proxy_settings,
+		METH_NOARGS,
+		NULL,
+	},
+	{
+		"_get_proxies",
+		(PyCFunction)get_proxies,
+		METH_NOARGS,
+		NULL,
+	},
+	{ 0, 0, 0, 0 }
+};
+
+void init_scproxy(void)
+{
+	(void)Py_InitModule4("_scproxy", mod_methods, NULL, NULL, PYTHON_API_VERSION);
+}
diff --git a/Misc/NEWS b/Misc/NEWS
index cac78e1..bdd121c 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -379,6 +379,8 @@ Core and Builtins
 Library
 -------
 
+- Issue #6851: Fix urllib.urlopen crash on secondairy threads on OSX 10.6
+
 - Issue #4606: Passing 'None' if ctypes argtype is set to POINTER(...)
   does now always result in NULL.
 
diff --git a/setup.py b/setup.py
index e128697..adc72c8 100644
--- a/setup.py
+++ b/setup.py
@@ -1400,6 +1400,17 @@ class PyBuildExt(build_ext):
             addMacExtension('_CF', core_kwds, ['cf/pycfbridge.c'])
             addMacExtension('autoGIL', core_kwds)
 
+            # _scproxy
+            sc_kwds = {
+                'extra_compile_args': carbon_extra_compile_args,
+                'extra_link_args': [
+                    '-framework', 'SystemConfiguration',
+                    '-framework', 'CoreFoundation'
+                ],
+            }
+            addMacExtension("_scproxy", sc_kwds)
+
+
             # Carbon
             carbon_kwds = {'extra_compile_args': carbon_extra_compile_args,
                            'extra_link_args': ['-framework', 'Carbon'],