Http cache: Avoid resuming (and keeping) truncated entries...

net/http/http_cache_transaction.cc

 // Copyright (c) 2006-2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/http/http_cache_transaction.h"
 
 #include "base/compiler_specific.h"
 
 #if defined(OS_POSIX)
 #include <unistd.h>
@@ skipping 530 matching lines @@
   DCHECK(mode_ & WRITE);
 
   // Don't set the flag for sparse entries.
   if (partial_.get() && !truncated_)
     return true;
 
   // Double check that there is something worth keeping.
   if (!entry_->disk_entry->GetDataSize(kResponseContentIndex))
     return false;
 
+  if (response_.headers->GetContentLength() <= 0 ||
+      response_.headers->HasHeaderValue("Accept-Ranges", "none") ||
+      !response_.headers->HasStrongValidators())
+    return false;
+
   truncated_ = true;
   target_state_ = STATE_NONE;
   next_state_ = STATE_CACHE_WRITE_TRUNCATED_RESPONSE;
   DoLoop(OK);
   return true;
 }
 
 void HttpCache::Transaction::DoCallback(int rv) {
   DCHECK(rv != ERR_IO_PENDING);
   DCHECK(callback_);
@@ skipping 574 matching lines @@
       // We don't want to switch to WRITE mode if we don't have this block of a
       // byte-range request because we may have other parts cached.
       custom_request_->extra_headers.append("If-Range: ");
     } else {
       custom_request_->extra_headers.append("If-None-Match: ");
     }
     custom_request_->extra_headers.append(etag_value);
     custom_request_->extra_headers.append("\r\n");
     // For byte-range requests, make sure that we use only one way to validate
     // the request.
-    if (partial_.get())
+    if (partial_.get() && !partial_->IsCurrentRangeCached())
       return true;
   }
 
   if (!last_modified_value.empty()) {
     if (partial_.get() && !partial_->IsCurrentRangeCached()) {
       custom_request_->extra_headers.append("If-Range: ");
     } else {
       custom_request_->extra_headers.append("If-Modified-Since: ");
     }
     custom_request_->extra_headers.append(last_modified_value);
@@ skipping 61 matching lines @@
 
     if (response_code == 304 && partial_->ResponseHeadersOK(headers))
       return true;
   } else {
     // We asked for "If-Range: " so a 206 means just another range.
     if (partial_response && partial_->ResponseHeadersOK(headers)) {
       *partial_content = true;
       return true;
     }
 
-    // 304 is not expected here, but we'll spare the entry.
+    // 304 is not expected here, but we'll spare the entry (unless it was
+    // truncated).
+    if (truncated_)
+      failure = true;
   }
 
   if (failure) {
     // We cannot truncate this entry, it has to be deleted.
     DoomPartialEntry(false);
     mode_ = NONE;
     if (!reading_ && !partial_->IsLastRange()) {
       // We'll attempt to issue another network request, this time without us
       // messing up the headers.
       partial_->RestoreHeaders(&custom_request_->extra_headers);
@@ skipping 432 matching lines @@
     response_.cert_request_info = response->cert_request_info;
   }
   return result;
 }
 
 void HttpCache::Transaction::OnIOComplete(int result) {
   DoLoop(result);
 }
 
 }  // namespace net