widget/LSBUtils.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  *
   3  * This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "LSBUtils.h"
   8
   9 #include <unistd.h>
  10 #include "base/process_util.h"
  11 #include "mozilla/FileUtils.h"
  12 #include "mozilla/Result.h"
  13 #include "mozilla/ResultVariant.h"
  14 #include "mozilla/ipc/LaunchError.h"
  15
  16 namespace mozilla::widget::lsb {
  17
  18 static const char* gLsbReleasePath = "/usr/bin/lsb_release";
  19
  20 bool GetLSBRelease(nsACString& aDistributor, nsACString& aDescription,
  21                    nsACString& aRelease, nsACString& aCodename) {
  22   if (access(gLsbReleasePath, R_OK) != 0) return false;
  23
  24   int pipefd[2];
  25   if (pipe(pipefd) == -1) {
  26     NS_WARNING("pipe() failed!");
  27     return false;
  28   }
  29
  30   std::vector<std::string> argv = {gLsbReleasePath, "-idrc"};
  31
  32   base::LaunchOptions options;
  33   options.fds_to_remap.push_back({pipefd[1], STDOUT_FILENO});
  34   options.wait = true;
  35
  36   base::ProcessHandle process;
  37   Result<Ok, ipc::LaunchError> err =
  38       base::LaunchApp(argv, std::move(options), &process);
  39   close(pipefd[1]);
  40   if (err.isErr()) {
  41     NS_WARNING("Failed to spawn lsb_release!");
  42     close(pipefd[0]);
  43     return false;
  44   }
  45
  46   ScopedCloseFile stream(fdopen(pipefd[0], "r"));
  47   if (!stream) {
  48     NS_WARNING("Could not wrap fd!");
  49     close(pipefd[0]);
  50     return false;
  51   }
  52
  53   char dist[256], desc[256], release[256], codename[256];
  54   if (fscanf(stream,
  55              "Distributor ID:\t%255[^\n]\n"
  56              "Description:\t%255[^\n]\n"
  57              "Release:\t%255[^\n]\n"
  58              "Codename:\t%255[^\n]\n",
  59              dist, desc, release, codename) != 4) {
  60     NS_WARNING("Failed to parse lsb_release!");
  61     return false;
  62   }
  63
  64   aDistributor.Assign(dist);
  65   aDescription.Assign(desc);
  66   aRelease.Assign(release);
  67   aCodename.Assign(codename);
  68   return true;
  69 }
  70
  71 }  // namespace mozilla::widget::lsb