ScopedProcessInformation protects against process/thread handle leaks from CreateProcess calls.

base/process_util_win.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 "base/process_util.h"
 
 #include <fcntl.h>
 #include <io.h>
 #include <windows.h>
 #include <userenv.h>
 #include <psapi.h>
 
 #include <ios>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/debug/stack_trace.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/sys_info.h"
 #include "base/win/object_watcher.h"
 #include "base/win/scoped_handle.h"
+#include "base/win/scoped_process_information.h"
 #include "base/win/windows_version.h"
 
 // userenv.dll is required for CreateEnvironmentBlock().
 #pragma comment(lib, "userenv.lib")
 
 namespace base {
 
 namespace {
 
 // System pagesize. This value remains constant on x86/64 architectures.
@@ skipping 263 matching lines @@
 
 bool LaunchProcess(const string16& cmdline,
                    const LaunchOptions& options,
                    ProcessHandle* process_handle) {
   STARTUPINFO startup_info = {};
   startup_info.cb = sizeof(startup_info);
   if (options.empty_desktop_name)
     startup_info.lpDesktop = L"";
   startup_info.dwFlags = STARTF_USESHOWWINDOW;
   startup_info.wShowWindow = options.start_hidden ? SW_HIDE : SW_SHOW;
-  PROCESS_INFORMATION process_info;
 
   DWORD flags = 0;
 
   if (options.job_handle) {
     flags |= CREATE_SUSPENDED;
 
     // If this code is run under a debugger, the launched process is
     // automatically associated with a job object created by the debugger.
     // The CREATE_BREAKAWAY_FROM_JOB flag is used to prevent this.
     flags |= CREATE_BREAKAWAY_FROM_JOB;
   }
 
+  base::win::ScopedProcessInformation process_info;
+
   if (options.as_user) {
     flags |= CREATE_UNICODE_ENVIRONMENT;
     void* enviroment_block = NULL;
 
     if (!CreateEnvironmentBlock(&enviroment_block, options.as_user, FALSE))
       return false;
 
     BOOL launched =
         CreateProcessAsUser(options.as_user, NULL,
                             const_cast<wchar_t*>(cmdline.c_str()),
                             NULL, NULL, options.inherit_handles, flags,
                             enviroment_block, NULL, &startup_info,
-                            &process_info);
+                            process_info.Receive());
     DestroyEnvironmentBlock(enviroment_block);
     if (!launched)
       return false;
   } else {
     if (!CreateProcess(NULL,
                        const_cast<wchar_t*>(cmdline.c_str()), NULL, NULL,
                        options.inherit_handles, flags, NULL, NULL,
-                       &startup_info, &process_info)) {
+                       &startup_info, process_info.Receive())) {
       return false;
     }
   }
 
   if (options.job_handle) {
     if (0 == AssignProcessToJobObject(options.job_handle,
-                                      process_info.hProcess)) {
+                                      process_info.process_handle())) {
       DLOG(ERROR) << "Could not AssignProcessToObject.";
-      KillProcess(process_info.hProcess, kProcessKilledExitCode, true);
-      CloseHandle(process_info.hProcess);
-      CloseHandle(process_info.hThread);
+      KillProcess(process_info.process_handle(), kProcessKilledExitCode, true);
       return false;
     }
 
-    ResumeThread(process_info.hThread);
+    ResumeThread(process_info.thread_handle());
   }
 
-  // Handles must be closed or they will leak.
-  CloseHandle(process_info.hThread);
-
   if (options.wait)
-    WaitForSingleObject(process_info.hProcess, INFINITE);
+    WaitForSingleObject(process_info.process_handle(), INFINITE);
 
   // If the caller wants the process handle, we won't close it.
-  if (process_handle) {
-    *process_handle = process_info.hProcess;
-  } else {
-    CloseHandle(process_info.hProcess);
-  }
+  if (process_handle)
+    *process_handle = process_info.TakeProcessHandle();
+
   return true;
 }
 
 bool LaunchProcess(const CommandLine& cmdline,
                    const LaunchOptions& options,
                    ProcessHandle* process_handle) {
   return LaunchProcess(cmdline.GetCommandLineString(), options, process_handle);
 }
 
 bool SetJobObjectAsKillOnJobClose(HANDLE job_object) {
@@ skipping 45 matching lines @@
   win::ScopedHandle scoped_out_write(out_write);
 
   // Ensure the read handle to the pipe for STDOUT is not inherited.
   if (!SetHandleInformation(out_read, HANDLE_FLAG_INHERIT, 0)) {
     NOTREACHED() << "Failed to disabled pipe inheritance";
     return false;
   }
 
   std::wstring writable_command_line_string(cl.GetCommandLineString());
 
-  PROCESS_INFORMATION proc_info = { 0 };
+  base::win::ScopedProcessInformation proc_info;
   STARTUPINFO start_info = { 0 };
 
   start_info.cb = sizeof(STARTUPINFO);
   start_info.hStdOutput = out_write;
   // Keep the normal stdin and stderr.
   start_info.hStdInput = GetStdHandle(STD_INPUT_HANDLE);
   start_info.hStdError = GetStdHandle(STD_ERROR_HANDLE);
   start_info.dwFlags |= STARTF_USESTDHANDLES;
 
   // Create the child process.
   if (!CreateProcess(NULL,
                      &writable_command_line_string[0],
                      NULL, NULL,
                      TRUE,  // Handles are inherited.
-                     0, NULL, NULL, &start_info, &proc_info)) {
+                     0, NULL, NULL, &start_info, proc_info.Receive())) {
     NOTREACHED() << "Failed to start process";
     return false;
   }
 
-  // We don't need the thread handle, close it now.
-  CloseHandle(proc_info.hThread);
-
   // Close our writing end of pipe now. Otherwise later read would not be able
   // to detect end of child's output.
   scoped_out_write.Close();
 
   // Read output from the child process's pipe for STDOUT
   const int kBufferSize = 1024;
   char buffer[kBufferSize];
 
   for (;;) {
     DWORD bytes_read = 0;
     BOOL success = ReadFile(out_read, buffer, kBufferSize, &bytes_read, NULL);
     if (!success || bytes_read == 0)
       break;
     output->append(buffer, bytes_read);
   }
 
   // Let's wait for the process to finish.
-  WaitForSingleObject(proc_info.hProcess, INFINITE);
-  CloseHandle(proc_info.hProcess);
+  WaitForSingleObject(proc_info.process_handle(), INFINITE);
 
   return true;
 }
 
 bool KillProcess(ProcessHandle process, int exit_code, bool wait) {
   bool result = (TerminateProcess(process, exit_code) != FALSE);
   if (result && wait) {
     // The process may not end immediately due to pending I/O
     if (WAIT_OBJECT_0 != WaitForSingleObject(process, 60 * 1000))
       DLOG(ERROR) << "Error waiting for process exit: " << GetLastError();
@@ skipping 515 matching lines @@
 
   PERFORMANCE_INFORMATION info;
   if (!InternalGetPerformanceInfo(&info, sizeof(info))) {
     DLOG(ERROR) << "Failed to fetch internal performance info.";
     return 0;
   }
   return (info.CommitTotal * system_info.dwPageSize) / 1024;
 }
 
 }  // namespace base