intermodule_comm/nacl/nacl_imc.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 // NaCl inter-module communication primitives.
  34
  35 #ifdef __native_client__
  36 #include <nacl/nacl_imc.h>
  37 #else
  38 #include "native_client/intermodule_comm/nacl_imc.h"
  39 #endif  // __native_client__
  40
  41 #include <bits/mman.h>
  42 #include <errno.h>
  43 #include <stdio.h>
  44 #include <string.h>
  45 #include <sys/nacl_syscalls.h>
  46
  47 #include <algorithm>
  48
  49 namespace nacl {
  50
  51 bool WouldBlock() {
  52   return (errno == EAGAIN) ? true : false;
  53 }
  54
  55 int GetLastErrorString(char* buffer, size_t length) {
  56   // Note newlib provides only GNU version of strerror_r().
  57   if (buffer == NULL || length == 0) {
  58     errno = ERANGE;
  59     return -1;
  60   }
  61   char* message = strerror_r(errno, buffer, length);
  62   if (message != buffer) {
  63     size_t message_bytes = strlen(message) + 1;
  64     length = std::min(message_bytes, length);
  65     memmove(buffer, message, length);
  66     buffer[length - 1] = '\0';
  67   }
  68   return 0;
  69 }
  70
  71 Handle BoundSocket(const SocketAddress* address) {
  72   // TODO: Switch to the following once the make_bound_sock() prototype
  73   //              is cleaned up.
  74   // return make_bound_sock(address);
  75   return -1;
  76 }
  77
  78 int SocketPair(Handle pair[2]) {
  79   return imc_socketpair(pair);
  80 }
  81
  82 int Close(Handle handle) {
  83   return close(handle);
  84 }
  85
  86 int SendDatagram(Handle handle, const MessageHeader* message, int flags) {
  87   return imc_sendmsg(handle, reinterpret_cast<const NaClImcMsgHdr*>(message),
  88                      flags);
  89 }
  90
  91 int SendDatagramTo(Handle handle, const MessageHeader* message, int flags,
  92                    const SocketAddress* name) {
  93   return -1;  // TODO: how to implement this for NaCl?
  94 }
  95
  96 int ReceiveDatagram(Handle handle, MessageHeader* message, int flags) {
  97   return imc_recvmsg(handle, reinterpret_cast<NaClImcMsgHdr*>(message), flags);
  98 }
  99
 100 Handle CreateMemoryObject(size_t length) {
 101   return imc_mem_obj_create(length);
 102 }
 103
 104 void* Map(void* start, size_t length, int prot, int flags,
 105           Handle memory, off_t offset) {
 106   static int posix_prot[4] = {
 107     PROT_NONE,
 108     PROT_READ,
 109     PROT_WRITE,
 110     PROT_READ | PROT_WRITE
 111   };
 112
 113   int adjusted = 0;
 114   if (flags & kMapShared) {
 115     adjusted |= MAP_SHARED;
 116   }
 117   if (flags & kMapPrivate) {
 118     adjusted |= MAP_PRIVATE;
 119   }
 120   if (flags & kMapFixed) {
 121     adjusted |= MAP_FIXED;
 122   }
 123   return mmap(start, length, posix_prot[prot & 3], adjusted, memory, offset);
 124 }
 125
 126 int Unmap(void* start, size_t length) {
 127   return munmap(start, length);
 128 }
 129
 130 }  // namespace nacl