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 #include <string>
  42
  43 #include "native_client/intermodule_comm/nacl_imc.h"
  44
  45 namespace nacl {
  46
  47 /*
  48  * This class encapsulates the process of launching an instance of sel_ldr
  49  * to communicate over an IMC channel.
  50  */
  51 struct SelLdrLauncher {
  52  public:
  53   explicit SelLdrLauncher();
  54
  55   bool Start(const char* application_name,
  56              int imc_fd,
  57              int sel_ldr_argc,
  58              const char* sel_ldr_argv[],
  59              int application_argc,
  60              const char* application_argv[]);
  61
  62   ~SelLdrLauncher();
  63
  64   Handle child() const { return child_; }
  65   Handle channel() const { return channel_; }
  66   const char* GetApplicationName() const { return application_name_.c_str(); }
  67   static const char* GetPluginDirname();
  68
  69   // Returns true if SelLdrLauncher has launched an instance of sel_ldr, or
  70   // false if SelLdrLauncher has launched a native OS binary instead of sel_ldr
  71   // for debugging.
  72   bool IsSelLdr() const { return is_sel_ldr_; }
  73
  74  private:
  75   // application_argv can take a "$CHAN" as an argument which will be replaced
  76   // with `imc_fd` number if the target application is a NaCl module
  77   // and with `channel_` number if the target application is a native OS
  78   // binary.
  79   void BuildArgv(const char* sel_ldr_pathname,
  80                  const char* application_name,
  81                  int imc_fd,
  82                  Handle imc_channel_handle,
  83                  int sel_ldr_argc,
  84                  const char* sel_ldr_argv[],
  85                  int application_argc,
  86                  const char* application_argv[]);
  87
  88   // If subprocess creation fails, both child_ and channel_  are set to
  89   // kInvalidHandle.
  90  public:
  91   Handle child_;
  92   Handle channel_;
  93  private:
  94   int argc_;
  95   char const** argv_;
  96   // The following buffer is used as an argv element for mapping the imc
  97   // channel to a nacl descriptor.
  98   char channel_buf_[23];
  99   // The following buffer is used to save a string that replaces an application
 100   // argument "$CHAN".
 101   char channel_number_[19];
 102   // The following boolean value is set to true if SelLdrLauncher has launched
 103   // an instance of sel_ldr, or false if child_ is executing a native OS binary
 104   // instead of sel_ldr for debugging.
 105   bool is_sel_ldr_;
 106   std::string application_name_;
 107 };
 108
 109 }  // namespace nacl
 110
 111 #endif  // NATIVE_CLIENT_NONNACL_UTIL_SEL_LDR_LAUNCHER_H_