base/test/multiprocess_test_android.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/posix/global_descriptors.h"
   6 #include "base/test/multiprocess_test.h"
   7
   8 #include <unistd.h>
   9
  10 #include "base/containers/hash_tables.h"
  11 #include "base/logging.h"
  12 #include "testing/multiprocess_func_list.h"
  13
  14 namespace base {
  15
  16 // A very basic implementation for Android. On Android tests can run in an APK
  17 // and we don't have an executable to exec*. This implementation does the bare
  18 // minimum to execute the method specified by procname (in the child process).
  19 //  - |base_command_line| is ignored.
  20 //  - All options except |fds_to_remap| are ignored.
  21 ProcessHandle SpawnMultiProcessTestChild(const std::string& procname,
  22                                          const CommandLine& base_command_line,
  23                                          const LaunchOptions& options) {
  24   // TODO(viettrungluu): The FD-remapping done below is wrong in the presence of
  25   // cycles (e.g., fd1 -> fd2, fd2 -> fd1). crbug.com/326576
  26   FileHandleMappingVector empty;
  27   const FileHandleMappingVector* fds_to_remap =
  28       options.fds_to_remap ? options.fds_to_remap : &empty;
  29
  30   pid_t pid = fork();
  31
  32   if (pid < 0) {
  33     PLOG(ERROR) << "fork";
  34     return kNullProcessHandle;
  35   }
  36   if (pid > 0) {
  37     // Parent process.
  38     return pid;
  39   }
  40   // Child process.
  41   std::hash_set<int> fds_to_keep_open;
  42   for (FileHandleMappingVector::const_iterator it = fds_to_remap->begin();
  43        it != fds_to_remap->end(); ++it) {
  44     fds_to_keep_open.insert(it->first);
  45   }
  46   // Keep standard FDs (stdin, stdout, stderr, etc.) open since this
  47   // is not meant to spawn a daemon.
  48   int base = GlobalDescriptors::kBaseDescriptor;
  49   for (int fd = base; fd < getdtablesize(); ++fd) {
  50     if (fds_to_keep_open.find(fd) == fds_to_keep_open.end()) {
  51       close(fd);
  52     }
  53   }
  54   for (FileHandleMappingVector::const_iterator it = fds_to_remap->begin();
  55        it != fds_to_remap->end(); ++it) {
  56     int old_fd = it->first;
  57     int new_fd = it->second;
  58     if (dup2(old_fd, new_fd) < 0) {
  59       PLOG(FATAL) << "dup2";
  60     }
  61     close(old_fd);
  62   }
  63   _exit(multi_process_function_list::InvokeChildProcessTest(procname));
  64   return 0;
  65 }
  66
  67 }  // namespace base