chromecast/base/process_utils.cc

   1 // Copyright 2015 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 "chromecast/base/process_utils.h"
   6
   7 #include <errno.h>
   8 #include <stdio.h>
   9
  10 #include "base/logging.h"
  11 #include "base/safe_strerror_posix.h"
  12 #include "base/strings/string_util.h"
  13
  14 namespace chromecast {
  15
  16 bool GetAppOutput(const std::vector<std::string>& argv, std::string* output) {
  17   DCHECK(output);
  18
  19   // Join the args into one string, creating the command.
  20   std::string command = JoinString(argv, ' ');
  21
  22   // Open the process.
  23   FILE* fp = popen(command.c_str(), "r");
  24   if (!fp) {
  25     LOG(ERROR) << "popen (" << command << ") failed: " << safe_strerror(errno);
  26     return false;
  27   }
  28
  29   // Fill |output| with the stdout from the process.
  30   output->clear();
  31   while (!feof(fp)) {
  32     char buffer[256];
  33     size_t bytes_read = fread(buffer, 1, sizeof(buffer), fp);
  34     if (bytes_read <= 0)
  35       break;
  36     output->append(buffer, bytes_read);
  37   }
  38
  39   // pclose() function waits for the associated process to terminate and returns
  40   // the exit status.
  41   return (pclose(fp) == 0);
  42 }
  43
  44 }  // namespace chromecast