libmetrics -- release the shared file lock when closing, handle EINTR.

metrics_library.cc

 // Copyright (c) 2010 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.
 
 #include "metrics_library.h"
 
 #include <errno.h>
 #include <sys/file.h>
 #include <sys/stat.h>
 
 #include <cstdarg>
 #include <cstdio>
 #include <cstring>
 
+#include <base/eintr_wrapper.h>
+
 #define READ_WRITE_ALL_FILE_FLAGS \
   (S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)
 
 static const char kAutotestPath[] = "/var/log/metrics/autotest-events";
 static const char kUMAEventsPath[] = "/var/log/metrics/uma-events";
 static const char kConsentFile[] = "/home/chronos/Consent To Send Stats";
 static const int32_t kBufferSize = 1024;
 
 time_t MetricsLibrary::cached_enabled_time_ = 0;
 bool MetricsLibrary::cached_enabled_ = false;
@@ skipping 98 matching lines @@
     else
       cached_enabled_ = false;
   }
   return cached_enabled_;
 }
 
 bool MetricsLibrary::SendMessageToChrome(int32_t length, const char* message) {
   if (!AreMetricsEnabled())
     return true;
 
-  int chrome_fd = open(uma_events_file_,
-                       O_WRONLY | O_APPEND | O_CREAT,
-                       READ_WRITE_ALL_FILE_FLAGS);
+  int chrome_fd = HANDLE_EINTR(open(uma_events_file_,
+                                    O_WRONLY | O_APPEND | O_CREAT,
+                                    READ_WRITE_ALL_FILE_FLAGS));
   // If we failed to open it, return.
   if (chrome_fd < 0) {
     PrintError("open", uma_events_file_, errno);
     return false;
   }
 
   // Need to chmod because open flags are anded with umask. Ignore the
   // exit code -- a chronos process may fail chmoding because the file
   // has been created by a root process but that should be OK.
   fchmod(chrome_fd, READ_WRITE_ALL_FILE_FLAGS);
 
   // Grab an exclusive lock to protect Chrome from truncating
   // underneath us. Keep the file locked as briefly as possible.
-  if (flock(chrome_fd, LOCK_EX) < 0) {
+  if (HANDLE_EINTR(flock(chrome_fd, LOCK_EX)) < 0) {
     PrintError("flock", uma_events_file_, errno);
-    close(chrome_fd);
+    HANDLE_EINTR(close(chrome_fd));
     return false;
   }
 
   bool success = true;
-  if (write(chrome_fd, message, length) != length) {
+  if (HANDLE_EINTR(write(chrome_fd, message, length)) != length) {
     PrintError("write", uma_events_file_, errno);
     success = false;
   }
 
-  // Release the file lock and close file.
-  if (flock(chrome_fd, LOCK_UN) < 0) {
-    PrintError("unlock", uma_events_file_, errno);
-    success = false;
-  }
-  close(chrome_fd);
+  // Close the file and release the lock.
+  HANDLE_EINTR(close(chrome_fd));
   return success;
 }
 
 int32_t MetricsLibrary::FormatChromeMessage(int32_t buffer_size, char* buffer,
                                             const char* format, ...) {
   int32_t message_length;
   size_t len_size = sizeof(message_length);
 
   // Format the non-LENGTH contents in the buffer by leaving space for
   // LENGTH at the start of the buffer.
@@ skipping 85 matching lines @@
   int32_t message_length =
       FormatChromeMessage(kBufferSize, message,
                           "crash%c%s", '\0', crash_kind);
 
   if (message_length < 0)
     return false;
 
   // Send the message.
   return SendMessageToChrome(message_length, message);
 }