Recommit 68258 - Mark some functions that wait on other processes as unsafe f...

base/process_util_posix.cc

 // Copyright (c) 2010 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 <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <signal.h>
 #include <stdlib.h>
 #include <sys/resource.h>
 #include <sys/time.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <unistd.h>
 
 #include <limits>
 #include <set>
 
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/debug/stack_trace.h"
 #include "base/dir_reader_posix.h"
 #include "base/eintr_wrapper.h"
 #include "base/logging.h"
 #include "base/platform_thread.h"
 #include "base/process_util.h"
 #include "base/scoped_ptr.h"
 #include "base/stringprintf.h"
+#include "base/thread_restrictions.h"
 #include "base/time.h"
 #include "base/waitable_event.h"
 
 #if defined(OS_MACOSX)
 #include <crt_externs.h>
 #define environ (*_NSGetEnviron())
 #else
 extern char** environ;
 #endif
 
@@ skipping 507 matching lines @@
     for (size_t i = 0; i < argv.size(); i++)
       argv_cstr[i] = const_cast<char*>(argv[i].c_str());
     argv_cstr[argv.size()] = NULL;
     execvp(argv_cstr[0], argv_cstr.get());
     RAW_LOG(ERROR, "LaunchApp: failed to execvp:");
     RAW_LOG(ERROR, argv_cstr[0]);
     _exit(127);
   } else {
     // Parent process
     if (wait) {
+      // While this isn't strictly disk IO, waiting for another process to
+      // finish is the sort of thing ThreadRestrictions is trying to prevent.
+      base::ThreadRestrictions::AssertIOAllowed();
       pid_t ret = HANDLE_EINTR(waitpid(pid, 0, 0));
       DPCHECK(ret > 0);
     }
 
     if (process_handle)
       *process_handle = pid;
   }
 
   return true;
 }
@@ skipping 175 matching lines @@
 // Executes the application specified by |cl| and wait for it to exit. Stores
 // the output (stdout) in |output|. If |do_search_path| is set, it searches the
 // path for the application; in that case, |envp| must be null, and it will use
 // the current environment. If |do_search_path| is false, |cl| should fully
 // specify the path of the application, and |envp| will be used as the
 // environment. Redirects stderr to /dev/null. Returns true on success
 // (application launched and exited cleanly, with exit code indicating success).
 static bool GetAppOutputInternal(const CommandLine& cl, char* const envp[],
                                  std::string* output, size_t max_output,
                                  bool do_search_path) {
+  // Doing a blocking wait for another command to finish counts as IO.
+  base::ThreadRestrictions::AssertIOAllowed();
+
   int pipe_fd[2];
   pid_t pid;
   InjectiveMultimap fd_shuffle1, fd_shuffle2;
   const std::vector<std::string>& argv = cl.argv();
   scoped_array<char*> argv_cstr(new char*[argv.size() + 1]);
 
   fd_shuffle1.reserve(3);
   fd_shuffle2.reserve(3);
 
   // Either |do_search_path| should be false or |envp| should be null, but not
@@ skipping 130 matching lines @@
                       const ProcessFilter* filter) {
   bool exited_cleanly =
       WaitForProcessesToExit(executable_name, wait_milliseconds,
                              filter);
   if (!exited_cleanly)
     KillProcesses(executable_name, exit_code, filter);
   return exited_cleanly;
 }
 
 }  // namespace base