fixes bug 331825 "Unable to do conditional gets via XMLHttpRequest with 1.5.0.1, works in 1.0.7" r=biesi sr=bzbarsky

netwerk/protocol/http/src/nsHttpChannel.cpp

@@ -245,6 +245,17 @@ nsHttpChannel::AsyncCall(nsAsyncCallback funcPtr)
     return NS_DispatchToCurrentThread(event);
 }
 
+PRBool
+nsHttpChannel::RequestIsConditional()
+{
+    // Is our consumer issuing a conditional request?
+    return mRequestHead.PeekHeader(nsHttp::If_Modified_Since) ||
+           mRequestHead.PeekHeader(nsHttp::If_None_Match) ||
+           mRequestHead.PeekHeader(nsHttp::If_Unmodified_Since) ||
+           mRequestHead.PeekHeader(nsHttp::If_Match) ||
+           mRequestHead.PeekHeader(nsHttp::If_Range);
+}
+
 nsresult
 nsHttpChannel::Connect(PRBool firstTime)
 {
@@ -1226,7 +1237,8 @@ nsHttpChannel::OpenCacheEntry(PRBool offline, PRBool *delayed)
         // don't use the cache for other types of requests
         return NS_OK;
     }
-    else if (mRequestHead.PeekHeader(nsHttp::Range)) {
+
+    if (mRequestHead.PeekHeader(nsHttp::Range)) {
         // we don't support caching for byte range requests initiated
         // by our clients or via nsIResumableChannel.
         // XXX perhaps we could munge their byte range into the cache
@@ -1234,6 +1246,12 @@ nsHttpChannel::OpenCacheEntry(PRBool offline, PRBool *delayed)
         return NS_OK;
     }
 
+    if (RequestIsConditional()) {
+        // don't use the cache if our consumer is making a conditional request
+        // (see bug 331825).
+        return NS_OK;
+    }
+
     GenerateCacheKey(cacheKey);
 
     // Get a cache session with appropriate storage policy

netwerk/protocol/http/src/nsHttpChannel.h

@@ -143,6 +143,7 @@ private:
     // AsyncCall may be used to call a member function asynchronously.
     nsresult AsyncCall(nsAsyncCallback funcPtr);
 
+    PRBool   RequestIsConditional();
     nsresult Connect(PRBool firstTime = PR_TRUE);
     nsresult AsyncAbort(nsresult status);
     nsresult SetupTransaction();

netwerk/test/unit/test_bug331825.js

@@ -0,0 +1,37 @@
+var server;
+var BUGID = "331825";
+
+function handle_response(stream) {
+  var response = server.handler.headers("304 Not Modified") + "\r\n";
+  stream.write(response, response.length);
+}
+
+function TestListener() {
+}
+TestListener.prototype.onStartRequest = function(request, context) {
+}
+TestListener.prototype.onStopRequest = function(request, context, status) {
+  var channel = request.QueryInterface(Components.interfaces.nsIHttpChannel);
+  do_check_eq(channel.responseStatus, 304);
+
+  do_test_finished();
+}
+
+function run_test() {
+  // start server
+  server = new nsTestServ(4444);
+  server.handler["/bug" + BUGID] = handle_response;
+  server.startListening();
+
+  // make request
+  var channel =
+      Components.classes["@mozilla.org/network/io-service;1"].
+      getService(Components.interfaces.nsIIOService).
+      newChannel("http://localhost:4444/bug" + BUGID, null, null);
+
+  channel.QueryInterface(Components.interfaces.nsIHttpChannel);
+  channel.setRequestHeader("If-None-Match", "foobar", false);
+  channel.asyncOpen(new TestListener(), null);
+
+  do_test_pending();
+}