nonnacl_util/linux/sel_ldr_launcher_linux.cc

   1 /*
   2  * Copyright 2008, Google Inc.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met:
   8  *
   9  *     * Redistributions of source code must retain the above copyright
  10  * notice, this list of conditions and the following disclaimer.
  11  *     * Redistributions in binary form must reproduce the above
  12  * copyright notice, this list of conditions and the following disclaimer
  13  * in the documentation and/or other materials provided with the
  14  * distribution.
  15  *     * Neither the name of Google Inc. nor the names of its
  16  * contributors may be used to endorse or promote products derived from
  17  * this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  22  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  23  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  29  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32
  33 #include <sys/types.h>
  34 #include <sys/wait.h>
  35
  36 #include <fcntl.h>
  37 #include <libgen.h>
  38 #include <signal.h>
  39 #include <stdio.h>
  40 #include <string.h>
  41 #include <sys/param.h>
  42 #include <unistd.h>
  43
  44 #include "native_client/nonnacl_util/sel_ldr_launcher.h"
  45
  46 namespace nacl {
  47
  48 SelLdrLauncher::~SelLdrLauncher() {
  49   if (child_ != kInvalidHandle) {
  50     int status;
  51     // When used with the browser's invalidate functionality this
  52     // causes occasional deadlocks in nacl modules that have threads that have
  53     // not terminated when the main thread is being terminated.
  54     // TODO: Implement a whole-module shutdown RPC.
  55     // waitpid(child_, &status, 0);
  56   }
  57 }
  58
  59 SelLdrLauncher::SelLdrLauncher(const char* application_name,
  60                                int imc_fd,
  61                                int sel_ldr_argc,
  62                                const char* sel_ldr_argv[],
  63                                int application_argc,
  64                                const char* application_argv[])
  65     : is_sel_ldr_(true),
  66       application_name_(application_name) {
  67   Handle pair[2];
  68   const char* const kSelLdrBasename = "sel_ldr";
  69   const char* const kNaclPtraceBasename = "sel_ldr.trace";
  70   const char* plugin_dirname = GetPluginDirname();
  71   char sel_ldr_path[MAXPATHLEN + 1];
  72
  73   child_ = kInvalidHandle;
  74   channel_ = kInvalidHandle;
  75
  76   if (NULL == plugin_dirname) {
  77     // TODO: better reporting that we couldn't find sel_ldr.
  78     printf("GetPluginDirname returned NULL -- load failed\n");
  79     return;
  80   }
  81
  82   if (getenv("NACL_TRACE_SEL_LDR")) {
  83     snprintf(sel_ldr_path,
  84              sizeof(sel_ldr_path),
  85              "%s/%s",
  86              plugin_dirname,
  87              kNaclPtraceBasename);
  88   } else {
  89     snprintf(sel_ldr_path,
  90              sizeof(sel_ldr_path),
  91              "%s/%s",
  92              plugin_dirname,
  93              kSelLdrBasename);
  94   }
  95   printf("starting: %s %s\n", sel_ldr_path, application_name);
  96
  97   if (SocketPair(pair) == -1) {
  98     // TODO: better reporting that we couldn't create the socket pair.
  99     return;
 100   }
 101
 102   // Set environment variable to keep the Mac sel_ldr from stealing the focus.
 103   // TODO: change this to use a command line parameter rather than env.
 104   setenv("NACL_LAUNCHED_FROM_BROWSER", "1", 0);
 105   // Fork the sel_ldr process.
 106   child_ = fork();
 107   if (child_ == -1) {
 108     // TODO: better reporting that we couldn't fork.
 109     printf("fork failed\n");
 110     Close(pair[0]);
 111     Close(pair[1]);
 112     return;
 113   }
 114
 115   if (child_ == 0) {
 116     Close(pair[0]);
 117     BuildArgv(sel_ldr_path,
 118               application_name,
 119               imc_fd,
 120               pair[1],
 121               sel_ldr_argc,
 122               sel_ldr_argv,
 123               application_argc,
 124               application_argv);
 125     execv(sel_ldr_path, const_cast<char **>(argv_));
 126     perror("exec");
 127     printf("exec failed\n");
 128     _exit(EXIT_FAILURE);
 129   }
 130   Close(pair[1]);
 131   channel_ = pair[0];
 132
 133   int flags = fcntl(channel_, F_GETFD);
 134   if (flags != -1) {
 135     flags |= FD_CLOEXEC;
 136     fcntl(channel_, F_SETFD, flags);
 137   }
 138 }
 139
 140 }  // namespace nacl