AU: When server dies, don't retry forever

libcurl_http_fetcher.h

 // Copyright (c) 2009 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROMEOS_PLATFORM_UPDATE_ENGINE_LIBCURL_HTTP_FETCHER_H__
 #define CHROMEOS_PLATFORM_UPDATE_ENGINE_LIBCURL_HTTP_FETCHER_H__
 
 #include <map>
 #include <string>
 #include <curl/curl.h>
 #include <glib.h>
 #include "base/basictypes.h"
 #include "chromeos/obsolete_logging.h"
 #include "update_engine/http_fetcher.h"
 
 // This is a concrete implementation of HttpFetcher that uses libcurl to do the
 // http work.
 
 namespace chromeos_update_engine {
 
 class LibcurlHttpFetcher : public HttpFetcher {
  public:
   LibcurlHttpFetcher()
       : curl_multi_handle_(NULL), curl_handle_(NULL),
         timeout_source_(NULL), transfer_in_progress_(false),
-        idle_ms_(1000) {}
+        retry_count_(0), idle_ms_(1000) {}
 
   // Cleans up all internal state. Does not notify delegate
   ~LibcurlHttpFetcher();
 
   // Begins the transfer if it hasn't already begun.
   virtual void BeginTransfer(const std::string& url);
 
   // If the transfer is in progress, aborts the transfer early.
   // The transfer cannot be resumed.
   virtual void TerminateTransfer();
@@ skipping 29 matching lines @@
   static gboolean StaticFDCallback(GIOChannel *source,
                                    GIOCondition condition,
                                    gpointer data) {
     return reinterpret_cast<LibcurlHttpFetcher*>(data)->FDCallback(source,
                                                                    condition);
   }
   gboolean TimeoutCallback();
   static gboolean StaticTimeoutCallback(gpointer data) {
     return reinterpret_cast<LibcurlHttpFetcher*>(data)->TimeoutCallback();
   }
+  
+  gboolean RetryTimeoutCallback();
+  static gboolean StaticRetryTimeoutCallback(void* arg) {
+    return static_cast<LibcurlHttpFetcher*>(arg)->RetryTimeoutCallback();
+  }
 
   // Calls into curl_multi_perform to let libcurl do its work. Returns after
   // curl_multi_perform is finished, which may actually be after more than
   // one call to curl_multi_perform. This method will set up the glib run
   // loop with sources for future work that libcurl will do.
   // This method will not block.
   // Returns true if we should resume immediately after this call.
   bool CurlPerformOnce();
 
   // Sets up glib main loop sources as needed by libcurl. This is generally
@@ skipping 30 matching lines @@
 
   // The transfer size. -1 if not known.
   off_t transfer_size_;
 
   // How many bytes have been downloaded and sent to the delegate.
   off_t bytes_downloaded_;
 
   // If we resumed an earlier transfer, data offset that we used for the
   // new connection.  0 otherwise.
   off_t resume_offset_;
+  
+  // Number of resumes performed.
+  int retry_count_;
 
   long idle_ms_;
   DISALLOW_COPY_AND_ASSIGN(LibcurlHttpFetcher);
 };
 
 }  // namespace chromeos_update_engine
 
 #endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_LIBCURL_HTTP_FETCHER_H__