Http Cache: Detect Content_length mismatches and mark entries as

truncated when we do.

BUG=92944
TEST=net_unittests
Review URL: http://codereview.chromium.org/7650026

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@97390 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 55 insertions, 4 deletions

diff --git a/net/http/http_cache_transaction.cc b/net/http/http_cache_transaction.cc
index 4b51cd5..9b3b6e8 100644
--- a/net/http/http_cache_transaction.cc
+++ b/net/http/http_cache_transaction.cc
@@ -1369,7 +1369,8 @@ int HttpCache::Transaction::DoCacheWriteDataComplete(int result) {
     result = write_len_;
   } else if (!done_reading_ && entry_) {
     int current_size = entry_->disk_entry->GetDataSize(kResponseContentIndex);
-    if (response_.headers->GetContentLength() == current_size)
+    int64 body_size = response_.headers->GetContentLength();
+    if (body_size >= 0 && body_size <= current_size)
       done_reading_ = true;
   }
 
@@ -1380,8 +1381,13 @@ int HttpCache::Transaction::DoCacheWriteDataComplete(int result) {
       return DoPartialNetworkReadCompleted(result);
   }
 
-  if (result == 0)  // End of file.
-    DoneWritingToEntry(true);
+  if (result == 0) {
+    // End of file. This may be the result of a connection problem so see if we
+    // have to keep the entry around to be flagged as truncated later on.
+    if (done_reading_ || !entry_ || partial_.get() ||
+        response_.headers->GetContentLength() <= 0)
+      DoneWritingToEntry(true);
+  }
 
   return result;
 }
diff --git a/net/http/http_cache_unittest.cc b/net/http/http_cache_unittest.cc
index 9fbd49e..dceabf8 100644
--- a/net/http/http_cache_unittest.cc
+++ b/net/http/http_cache_unittest.cc
@@ -5125,7 +5125,7 @@ TEST(HttpCache, FilterCompletion) {
     trans->DoneReading();
   }
 
-  // Make sure that teh ActiveEntry is gone.
+  // Make sure that the ActiveEntry is gone.
   MessageLoop::current()->RunAllPending();
 
   // Read from the cache.
@@ -5135,3 +5135,48 @@ TEST(HttpCache, FilterCompletion) {
   EXPECT_EQ(1, cache.disk_cache()->open_count());
   EXPECT_EQ(1, cache.disk_cache()->create_count());
 }
+
+// Tests that we detect truncated rersources from the net when there is
+// a Content-Length header.
+TEST(HttpCache, TruncatedByContentLength) {
+  MockHttpCache cache;
+  TestCompletionCallback callback;
+
+  MockTransaction transaction(kSimpleGET_Transaction);
+  AddMockTransaction(&transaction);
+  transaction.response_headers = "Cache-Control: max-age=10000\n"
+                                 "Content-Length: 100\n";
+  RunTransactionTest(cache.http_cache(), transaction);
+  RemoveMockTransaction(&transaction);
+
+  // Read from the cache.
+  RunTransactionTest(cache.http_cache(), kSimpleGET_Transaction);
+
+  EXPECT_EQ(2, cache.network_layer()->transaction_count());
+  EXPECT_EQ(0, cache.disk_cache()->open_count());
+  EXPECT_EQ(2, cache.disk_cache()->create_count());
+}
+
+// Tests that we actually flag entries as truncated when we detect an error
+// from the net.
+TEST(HttpCache, TruncatedByContentLength2) {
+  MockHttpCache cache;
+  TestCompletionCallback callback;
+
+  MockTransaction transaction(kSimpleGET_Transaction);
+  AddMockTransaction(&transaction);
+  transaction.response_headers = "Cache-Control: max-age=10000\n"
+                                 "Content-Length: 100\n"
+                                 "Etag: foo\n";
+  RunTransactionTest(cache.http_cache(), transaction);
+  RemoveMockTransaction(&transaction);
+
+  // Verify that the entry is marked as incomplete.
+  disk_cache::Entry* entry;
+  ASSERT_TRUE(cache.OpenBackendEntry(kSimpleGET_Transaction.url, &entry));
+  net::HttpResponseInfo response;
+  bool truncated = false;
+  EXPECT_TRUE(MockHttpCache::ReadResponseInfo(entry, &response, &truncated));
+  EXPECT_TRUE(truncated);
+  entry->Close();
+}