Bug 3346: forward.cc:364: "entry->store_status == STORE_PENDING"

While the server writes the response to Store, the client side may
synchronously abort the entry. This happens, for example, when the
server receives a 304 response and handleIMSReply calls
sendClientOldEntry, which calls storeUnregister with our entry,
resulting in CheckQuickAbort.

Once server store write returns, if the server is done, it calls
FwdState::completed(). At that time, the server does not know that (and
should not care whether) the entry was aborted. Thus, we need to handle
aborted entries in FwdState::completed.

This is a Measurement Factory project.

=== modified file 'src/forward.cc'
--- src/forward.cc	2011-09-09 09:24:28 +0000
+++ src/forward.cc	2011-10-01 09:00:59 +0000
@@ -146,6 +146,11 @@
 
     flags.forward_completed = 1;
 
+    if (EBIT_TEST(entry->flags, ENTRY_ABORTED)) {
+        debugs(17, 3, HERE << "entry aborted");
+        return ;
+    }
+
 #if URL_CHECKSUM_DEBUG
 
     entry->mem_obj->checkUrlChecksum();
@@ -361,7 +366,6 @@
 void
 FwdState::complete()
 {
-    assert(entry->store_status == STORE_PENDING);
     debugs(17, 3, HERE << entry->url() << "\n\tstatus " << entry->getReply()->sline.status  );
 #if URL_CHECKSUM_DEBUG
 
@@ -1017,6 +1021,12 @@
 {
     StoreEntry *e = entry;
     http_status s;
+
+    if (EBIT_TEST(e->flags, ENTRY_ABORTED)) {
+        debugs(17, 3, HERE << "entry aborted");
+        return 0;
+    }
+
     assert(e->store_status == STORE_PENDING);
     assert(e->mem_obj);
 #if URL_CHECKSUM_DEBUG