nonnacl_util/sel_ldr_launcher.h

   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 // Utility class for launching sel_ldr.
  34
  35 #ifndef NATIVE_CLIENT_NONNACL_UTIL_SEL_LDR_LAUNCHER_H_
  36 #define NATIVE_CLIENT_NONNACL_UTIL_SEL_LDR_LAUNCHER_H_
  37
  38 #include <stdarg.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41
  42 #include "native_client/intermodule_comm/nacl_imc.h"
  43
  44 namespace nacl {
  45
  46 /*
  47  * This class encapsulates the process of launching an instance of sel_ldr
  48  * to communicate over an IMC channel.
  49  */
  50 struct SelLdrLauncher {
  51  public:
  52   explicit SelLdrLauncher(const char* application_name,
  53                           int imc_fd,
  54                           int sel_ldr_argc,
  55                           const char* sel_ldr_argv[],
  56                           int application_argc,
  57                           const char* application_argv[]);
  58
  59   ~SelLdrLauncher();
  60
  61   Handle child() const { return child_; }
  62   Handle channel() const { return channel_; }
  63
  64   // Returns true if SelLdrLauncher has launched an instance of sel_ldr, or
  65   // false if SelLdrLauncher has launched a native OS binary instead of sel_ldr
  66   // for debugging.
  67   bool IsSelLdr() const { return is_sel_ldr_; }
  68
  69  private:
  70   static const char* GetPluginDirname();
  71   // application_argv can take a "$CHAN" as an argument which will be replaced
  72   // with `imc_fd` number if the target application is a NaCl module
  73   // and with `channel_` number if the target application is a native OS
  74   // binary.
  75   void BuildArgv(const char* sel_ldr_pathname,
  76                  const char* application_name,
  77                  int imc_fd,
  78                  Handle imc_channel_handle,
  79                  int sel_ldr_argc,
  80                  const char* sel_ldr_argv[],
  81                  int application_argc,
  82                  const char* application_argv[]);
  83
  84   // If subprocess creation fails, both child_ and channel_  are set to
  85   // kInvalidHandle.
  86  public:
  87   Handle child_;
  88   Handle channel_;
  89  private:
  90   int argc_;
  91   char const** argv_;
  92   // The following buffer is used as an argv element for mapping the imc
  93   // channel to a nacl descriptor.
  94   char channel_buf_[23];
  95   // The following buffer is used to save a string that replaces an application
  96   // argument "$CHAN".
  97   char channel_number_[19];
  98   // The following boolean value is set to true if SelLdrLauncher has launched
  99   // an instance of sel_ldr, or false if child_ is executing a native OS binary
 100   // instead of sel_ldr for debugging.
 101   bool is_sel_ldr_;
 102 };
 103
 104 }  // namespace nacl
 105
 106 #endif  // NATIVE_CLIENT_NONNACL_UTIL_SEL_LDR_LAUNCHER_H_