michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
michael@0:  * vim: sw=2 ts=8 et :
michael@0:  */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include <android/log.h>
michael@0: #include <errno.h>
michael@0: #include <fcntl.h>
michael@0: #include <string.h>
michael@0: #include <sys/ioctl.h>
michael@0: #include <sys/mman.h>
michael@0: #include <sys/stat.h>
michael@0: #include <sys/types.h>
michael@0: #include <unistd.h>
michael@0: 
michael@0: #include "base/process_util.h"
michael@0: 
michael@0: #include "SharedMemoryBasic.h"
michael@0: 
michael@0: //
michael@0: // Temporarily go directly to the kernel interface until we can
michael@0: // interact better with libcutils.
michael@0: //
michael@0: #include <linux/ashmem.h>
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace ipc {
michael@0: 
michael@0: static void
michael@0: LogError(const char* what)
michael@0: {
michael@0:   __android_log_print(ANDROID_LOG_ERROR, "Gecko",
michael@0:                       "%s: %s (%d)", what, strerror(errno), errno);
michael@0: }
michael@0: 
michael@0: SharedMemoryBasic::SharedMemoryBasic()
michael@0:   : mShmFd(-1)
michael@0:   , mMemory(nullptr)
michael@0: { }
michael@0: 
michael@0: SharedMemoryBasic::SharedMemoryBasic(const Handle& aHandle)
michael@0:   : mShmFd(aHandle.fd)
michael@0:   , mMemory(nullptr)
michael@0: { }
michael@0: 
michael@0: SharedMemoryBasic::~SharedMemoryBasic()
michael@0: {
michael@0:   Unmap();
michael@0:   Destroy();
michael@0: }
michael@0: 
michael@0: bool
michael@0: SharedMemoryBasic::Create(size_t aNbytes)
michael@0: {
michael@0:   NS_ABORT_IF_FALSE(-1 == mShmFd, "Already Create()d");
michael@0: 
michael@0:   // Carve a new instance off of /dev/ashmem
michael@0:   int shmfd = open("/" ASHMEM_NAME_DEF, O_RDWR, 0600);
michael@0:   if (-1 == shmfd) {
michael@0:     LogError("ShmemAndroid::Create():open");
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   if (ioctl(shmfd, ASHMEM_SET_SIZE, aNbytes)) {
michael@0:     LogError("ShmemAndroid::Unmap():ioctl(SET_SIZE)");
michael@0:     close(shmfd);
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   mShmFd = shmfd;
michael@0:   Created(aNbytes);
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: bool
michael@0: SharedMemoryBasic::Map(size_t nBytes)
michael@0: {
michael@0:   NS_ABORT_IF_FALSE(nullptr == mMemory, "Already Map()d");
michael@0: 
michael@0:   mMemory = mmap(nullptr, nBytes,
michael@0:                  PROT_READ | PROT_WRITE,
michael@0:                  MAP_SHARED,
michael@0:                  mShmFd,
michael@0:                  0);
michael@0:   if (MAP_FAILED == mMemory) {
michael@0:     LogError("ShmemAndroid::Map()");
michael@0:     mMemory = nullptr;
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   Mapped(nBytes);
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: bool
michael@0: SharedMemoryBasic::ShareToProcess(base::ProcessHandle/*unused*/,
michael@0:                                   Handle* aNewHandle)
michael@0: {
michael@0:   NS_ABORT_IF_FALSE(mShmFd >= 0, "Should have been Create()d by now");
michael@0: 
michael@0:   int shmfdDup = dup(mShmFd);
michael@0:   if (-1 == shmfdDup) {
michael@0:     LogError("ShmemAndroid::ShareToProcess()");
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   aNewHandle->fd = shmfdDup;
michael@0:   aNewHandle->auto_close = true;
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: void
michael@0: SharedMemoryBasic::Unmap()
michael@0: {
michael@0:   if (!mMemory) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   if (munmap(mMemory, Size())) {
michael@0:     LogError("ShmemAndroid::Unmap()");
michael@0:   }
michael@0:   mMemory = nullptr;
michael@0: }
michael@0: 
michael@0: void
michael@0: SharedMemoryBasic::Destroy()
michael@0: {
michael@0:   if (mShmFd > 0) {
michael@0:     close(mShmFd);
michael@0:   }
michael@0: }
michael@0: 
michael@0: } // namespace ipc
michael@0: } // namespace mozilla