Handle ERR_PAC_SCRIPT_TERMINATED in ProxyService.

net/proxy/proxy_service.cc

 // Copyright (c) 2012 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/proxy/proxy_service.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 862 matching lines @@
   // Returns true if Cancel() has been called.
   bool was_cancelled() const {
     return user_callback_.is_null();
   }
 
   // Helper to call after ProxyResolver completion (both synchronous and
   // asynchronous). Fixes up the result that is to be returned to user.
   int QueryDidComplete(int result_code) {
     DCHECK(!was_cancelled());
 
+    // Clear |resolve_job_| so is_started() returns false while
+    // DidFinishResolvingProxy() runs.
+    resolve_job_ = nullptr;
+
     // Note that DidFinishResolvingProxy might modify |results_|.
     int rv = service_->DidFinishResolvingProxy(url_, load_flags_,
                                                network_delegate_, results_,
                                                result_code, net_log_);
 
     // Make a note in the results which configuration was in use at the
     // time of the resolve.
     results_->config_id_ = config_id_;
     results_->config_source_ = config_source_;
     results_->did_use_pac_script_ = true;
     results_->proxy_resolve_start_time_ = proxy_resolve_start_time_;
     results_->proxy_resolve_end_time_ = TimeTicks::Now();
 
     // Reset the state associated with in-progress-resolve.
-    resolve_job_ = NULL;
     config_id_ = ProxyConfig::kInvalidConfigID;
     config_source_ = PROXY_CONFIG_SOURCE_UNKNOWN;
 
     return rv;
   }
 
   BoundNetLog* net_log() { return &net_log_; }
 
   LoadState GetLoadState() const {
     if (is_started())
@@ skipping 496 matching lines @@
     if (net_log.IsLogging()) {
       net_log.AddEvent(
           NetLog::TYPE_PROXY_SERVICE_RESOLVED_PROXY_LIST,
           base::Bind(&NetLogFinishedResolvingProxyCallback, result));
     }
     result->DeprioritizeBadProxies(proxy_retry_info_);
   } else {
     net_log.AddEventWithNetErrorCode(
         NetLog::TYPE_PROXY_SERVICE_RESOLVED_PROXY_LIST, result_code);
 
+    if (result_code == ERR_PAC_SCRIPT_TERMINATED) {
+      // If the ProxyResolver crashed, force it to be re-initialized for the
+      // next request by resetting the proxy config. If there are other
+      // requests, trigger the recreation immediately so those requests retry.
+      bool requests_in_progress = false;
+      for (const auto& request : pending_requests_) {
+        if (request->is_started()) {

[eroman, 2015/04/15 00:56:52]

why not reset the config whenever there are requests (regardless if they have
been started) ?

[Sam McNally, 2015/04/15 04:35:56]

Done.

+          requests_in_progress = true;
+          break;
+        }
+      }
+      ResetProxyConfig(false);
+      if (requests_in_progress)
+        ApplyProxyConfigIfAvailable();
+    }
+
     if (!config_.pac_mandatory()) {

[eroman, 2015/04/15 00:56:52]

config_ should not be tested and relied upon after calling ResetProxyConfig()
above. The state machine has been reset.

[Sam McNally, 2015/04/15 04:35:56]

Done.

       // Fall-back to direct when the proxy resolver fails. This corresponds
       // with a javascript runtime error in the PAC script.
       //
       // This implicit fall-back to direct matches Firefox 3.5 and
       // Internet Explorer 8. For more information, see:
       //
       // http://www.chromium.org/developers/design-documents/proxy-settings-fallback
       result->UseDirect();
       result_code = OK;
 
@@ skipping 219 matching lines @@
   State previous_state = ResetProxyConfig(false);
   if (previous_state != STATE_NONE)
     ApplyProxyConfigIfAvailable();
 }
 
 void ProxyService::OnDNSChanged() {
   OnIPAddressChanged();
 }
 
 }  // namespace net