Prototype implementation of zygotes

base/logging.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 "base/logging.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 typedef HANDLE FileHandle;
 typedef HANDLE MutexHandle;
 #elif defined(OS_MACOSX)
 #include <CoreFoundation/CoreFoundation.h>
 #include <mach/mach.h>
 #include <mach/mach_time.h>
 #include <mach-o/dyld.h>
 #elif defined(OS_LINUX)
 #include <sys/syscall.h>
 #include <time.h>
 #endif
 
 #if defined(OS_POSIX)
+#include <fcntl.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
 #include <unistd.h>
 #define MAX_PATH PATH_MAX
 typedef FILE* FileHandle;
 typedef pthread_mutex_t* MutexHandle;
 #endif
 
 #include <ctime>
 #include <iomanip>
 #include <cstring>
 #include <algorithm>
 
 #include "base/base_switches.h"
 #include "base/command_line.h"
 #include "base/debug_util.h"
 #include "base/lock_impl.h"
+#include "base/reserved_file_descriptors.h"
 #include "base/string_piece.h"
 #include "base/string_util.h"
 #include "base/sys_string_conversions.h"
 
 namespace logging {
 
 bool g_enable_dcheck = false;
 
 const char* const log_severity_names[LOG_NUM_SEVERITIES] = {
   "INFO", "WARNING", "ERROR", "ERROR_REPORT", "FATAL" };
@@ skipping 148 matching lines @@
       log_file = CreateFile(L".\\debug.log", GENERIC_WRITE,
                             FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
                             OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
       if (log_file == INVALID_HANDLE_VALUE || log_file == NULL) {
         log_file = NULL;
         return false;
       }
     }
     SetFilePointer(log_file, 0, 0, FILE_END);
 #elif defined(OS_POSIX)
+    // Reserve global fd slots.
+    int reserved_fds[kReservedFds];
+    for (int i=0; i < kReservedFds; i++)
+      reserved_fds[i] = open("/dev/null", O_RDONLY, 0);
+
     log_file = fopen(log_file_name->c_str(), "a");
+
+    // Release the reserved fds.
+    for (int i=0; i < kReservedFds; i++)
+      close(reserved_fds[i]);
+
     if (log_file == NULL)
       return false;
 #endif
   }
 
   return true;
 }
 
+#if defined(OS_LINUX)
+int GetLoggingFileDescriptor() {
+  // No locking needed, since this is only called by the zygote server,
+  // which is single-threaded.
+  if (log_file)
+    return fileno(log_file);
+  return -1;
+}
+#endif
+
 void InitLogMutex() {
 #if defined(OS_WIN)
   if (!log_mutex) {
     // \ is not a legal character in mutex names so we replace \ with /
     std::wstring safe_name(*log_file_name);
     std::replace(safe_name.begin(), safe_name.end(), '\\', '/');
     std::wstring t(L"Global\\");
     t.append(safe_name);
     log_mutex = ::CreateMutex(NULL, FALSE, t.c_str());
   }
@@ skipping 332 matching lines @@
 
   CloseFile(log_file);
   log_file = NULL;
 }
 
 }  // namespace logging
 
 std::ostream& operator<<(std::ostream& out, const wchar_t* wstr) {
   return out << base::SysWideToUTF8(std::wstring(wstr));
 }