gecko-dev/dom/system/gonk/VolumeManager.cpp

459 строки
12 KiB
C++
Исходник Обычный вид История

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "VolumeManager.h"
#include "Volume.h"
#include "VolumeCommand.h"
#include "VolumeManagerLog.h"
#include "VolumeServiceTest.h"
#include "nsWhitespaceTokenizer.h"
#include "nsXULAppAPI.h"
#include "base/message_loop.h"
#include "mozilla/Scoped.h"
#include "mozilla/StaticPtr.h"
#include <android/log.h>
#include <cutils/sockets.h>
#include <fcntl.h>
#include <sys/socket.h>
namespace mozilla {
namespace system {
static StaticRefPtr<VolumeManager> sVolumeManager;
VolumeManager::STATE VolumeManager::mState = VolumeManager::UNINITIALIZED;
VolumeManager::StateObserverList VolumeManager::mStateObserverList;
/***************************************************************************/
VolumeManager::VolumeManager()
: mSocket(-1),
mCommandPending(false),
mRcvIdx(0)
{
DBG("VolumeManager constructor called");
}
VolumeManager::~VolumeManager()
{
}
//static
size_t
VolumeManager::NumVolumes()
{
if (!sVolumeManager) {
return 0;
}
return sVolumeManager->mVolumeArray.Length();
}
//static
TemporaryRef<Volume>
VolumeManager::GetVolume(size_t aIndex)
{
MOZ_ASSERT(aIndex < NumVolumes());
return sVolumeManager->mVolumeArray[aIndex];
}
//static
VolumeManager::STATE
VolumeManager::State()
{
return mState;
}
//static
const char *
VolumeManager::StateStr(VolumeManager::STATE aState)
{
switch (aState) {
case UNINITIALIZED: return "Uninitialized";
case STARTING: return "Starting";
case VOLUMES_READY: return "Volumes Ready";
}
return "???";
}
//static
void
VolumeManager::SetState(STATE aNewState)
{
if (mState != aNewState) {
LOG("changing state from '%s' to '%s'",
StateStr(mState), StateStr(aNewState));
mState = aNewState;
mStateObserverList.Broadcast(StateChangedEvent());
}
}
//static
void
VolumeManager::RegisterStateObserver(StateObserver *aObserver)
{
mStateObserverList.AddObserver(aObserver);
}
//static
void VolumeManager::UnregisterStateObserver(StateObserver *aObserver)
{
mStateObserverList.RemoveObserver(aObserver);
}
//static
TemporaryRef<Volume>
VolumeManager::FindVolumeByName(const nsCSubstring &aName)
{
if (!sVolumeManager) {
return NULL;
}
VolumeArray::size_type numVolumes = NumVolumes();
VolumeArray::index_type volIndex;
for (volIndex = 0; volIndex < numVolumes; volIndex++) {
RefPtr<Volume> vol = GetVolume(volIndex);
if (vol->Name().Equals(aName)) {
return vol;
}
}
return NULL;
}
//static
TemporaryRef<Volume>
VolumeManager::FindAddVolumeByName(const nsCSubstring &aName)
{
RefPtr<Volume> vol = FindVolumeByName(aName);
if (vol) {
return vol;
}
// No volume found, create and add a new one.
vol = new Volume(aName);
sVolumeManager->mVolumeArray.AppendElement(vol);
return vol;
}
class VolumeListCallback : public VolumeResponseCallback
{
virtual void ResponseReceived(const VolumeCommand *aCommand)
{
switch (ResponseCode()) {
case ResponseCode::VolumeListResult: {
// Each line will look something like:
//
// sdcard /mnt/sdcard 1
//
// So for each volume that we get back, we update any volumes that
// we have of the same name, or add new ones if they don't exist.
nsCWhitespaceTokenizer tokenizer(ResponseStr());
nsDependentCSubstring volName(tokenizer.nextToken());
RefPtr<Volume> vol = VolumeManager::FindAddVolumeByName(volName);
vol->HandleVoldResponse(ResponseCode(), tokenizer);
break;
}
case ResponseCode::CommandOkay: {
// We've received the list of volumes. Tell anybody who
// is listening that we're open for business.
VolumeManager::SetState(VolumeManager::VOLUMES_READY);
break;
}
}
}
};
bool
VolumeManager::OpenSocket()
{
SetState(STARTING);
if ((mSocket.rwget() = socket_local_client("vold",
ANDROID_SOCKET_NAMESPACE_RESERVED,
SOCK_STREAM)) < 0) {
ERR("Error connecting to vold: (%s) - will retry", strerror(errno));
return false;
}
// add FD_CLOEXEC flag
int flags = fcntl(mSocket.get(), F_GETFD);
if (flags == -1) {
return false;
}
flags |= FD_CLOEXEC;
if (fcntl(mSocket.get(), F_SETFD, flags) == -1) {
return false;
}
// set non-blocking
if (fcntl(mSocket.get(), F_SETFL, O_NONBLOCK) == -1) {
return false;
}
if (!MessageLoopForIO::current()->
WatchFileDescriptor(mSocket.get(),
true,
MessageLoopForIO::WATCH_READ,
&mReadWatcher,
this)) {
return false;
}
LOG("Connected to vold");
PostCommand(new VolumeListCommand(new VolumeListCallback));
return true;
}
//static
void
VolumeManager::PostCommand(VolumeCommand *aCommand)
{
if (!sVolumeManager) {
ERR("VolumeManager not initialized. Dropping command '%s'", aCommand->Data());
return;
}
aCommand->SetPending(true);
DBG("Sending command '%s'", aCommand->Data());
// vold can only process one command at a time, so add our command
// to the end of the command queue.
sVolumeManager->mCommands.push(aCommand);
if (!sVolumeManager->mCommandPending) {
// There aren't any commands currently being processed, so go
// ahead and kick this one off.
sVolumeManager->mCommandPending = true;
sVolumeManager->WriteCommandData();
}
}
/***************************************************************************
* The WriteCommandData initiates sending of a command to vold. Since
* we're running on the IOThread and not allowed to block, WriteCommandData
* will write as much data as it can, and if not all of the data can be
* written then it will setup a file descriptor watcher and
* OnFileCanWriteWithoutBlocking will call WriteCommandData to write out
* more of the command data.
*/
void
VolumeManager::WriteCommandData()
{
if (mCommands.size() == 0) {
return;
}
VolumeCommand *cmd = mCommands.front();
if (cmd->BytesRemaining() == 0) {
// All bytes have been written. We're waiting for a response.
return;
}
// There are more bytes left to write. Try to write them all.
ssize_t bytesWritten = write(mSocket.get(), cmd->Data(), cmd->BytesRemaining());
if (bytesWritten < 0) {
ERR("Failed to write %d bytes to vold socket", cmd->BytesRemaining());
Restart();
return;
}
DBG("Wrote %ld bytes (of %d)", bytesWritten, cmd->BytesRemaining());
cmd->ConsumeBytes(bytesWritten);
if (cmd->BytesRemaining() == 0) {
return;
}
// We were unable to write all of the command bytes. Setup a watcher
// so we'll get called again when we can write without blocking.
if (!MessageLoopForIO::current()->
WatchFileDescriptor(mSocket.get(),
false, // one-shot
MessageLoopForIO::WATCH_WRITE,
&mWriteWatcher,
this)) {
ERR("Failed to setup write watcher for vold socket");
Restart();
}
}
void
VolumeManager::OnFileCanReadWithoutBlocking(int aFd)
{
MOZ_ASSERT(aFd == mSocket.get());
while (true) {
ssize_t bytesRemaining = read(aFd, &mRcvBuf[mRcvIdx], sizeof(mRcvBuf) - mRcvIdx);
if (bytesRemaining < 0) {
if ((errno == EAGAIN) || (errno == EWOULDBLOCK)) {
return;
}
if (errno == EINTR) {
continue;
}
ERR("Unknown read error: %d (%s) - restarting", errno, strerror(errno));
Restart();
return;
}
if (bytesRemaining == 0) {
// This means that vold probably crashed
ERR("Vold appears to have crashed - restarting");
Restart();
return;
}
// We got some data. Each line is terminated by a null character
DBG("Read %ld bytes", bytesRemaining);
while (bytesRemaining > 0) {
bytesRemaining--;
if (mRcvBuf[mRcvIdx] == '\0') {
// We found a line terminator. Each line is formatted as an
// integer response code followed by the rest of the line.
// Fish out the response code.
char *endPtr;
int responseCode = strtol(mRcvBuf, &endPtr, 10);
if (*endPtr == ' ') {
endPtr++;
}
// Now fish out the rest of the line after the response code
nsDependentCString responseLine(endPtr, &mRcvBuf[mRcvIdx] - endPtr);
DBG("Rcvd: %d '%s'", responseCode, responseLine.Data());
if (responseCode >= ResponseCode::UnsolicitedInformational) {
// These are unsolicited broadcasts. We intercept these and process
// them ourselves
HandleBroadcast(responseCode, responseLine);
} else {
// Everything else is considered to be part of the command response.
if (mCommands.size() > 0) {
VolumeCommand *cmd = mCommands.front();
cmd->HandleResponse(responseCode, responseLine);
if (responseCode >= ResponseCode::CommandOkay) {
// That's a terminating response. We can remove the command.
mCommands.pop();
mCommandPending = false;
// Start the next command, if there is one.
WriteCommandData();
}
} else {
ERR("Response with no command");
}
}
if (bytesRemaining > 0) {
// There is data in the receive buffer beyond the current line.
// Shift it down to the beginning.
memmove(&mRcvBuf[0], &mRcvBuf[mRcvIdx + 1], bytesRemaining);
}
mRcvIdx = 0;
} else {
mRcvIdx++;
}
}
}
}
void
VolumeManager::OnFileCanWriteWithoutBlocking(int aFd)
{
MOZ_ASSERT(aFd == mSocket.get());
WriteCommandData();
}
void
VolumeManager::HandleBroadcast(int aResponseCode, nsCString &aResponseLine)
{
// Format of the line is something like:
//
// Volume sdcard /mnt/sdcard state changed from 7 (Shared-Unmounted) to 1 (Idle-Unmounted)
//
// So we parse out the volume name and the state after the string " to "
nsCWhitespaceTokenizer tokenizer(aResponseLine);
tokenizer.nextToken(); // The word "Volume"
nsDependentCSubstring volName(tokenizer.nextToken());
RefPtr<Volume> vol = FindVolumeByName(volName);
if (!vol) {
return;
}
vol->HandleVoldResponse(aResponseCode, tokenizer);
}
void
VolumeManager::Restart()
{
mReadWatcher.StopWatchingFileDescriptor();
mWriteWatcher.StopWatchingFileDescriptor();
while (!mCommands.empty()) {
mCommands.pop();
}
mCommandPending = false;
mSocket.dispose();
mRcvIdx = 0;
Start();
}
//static
void
VolumeManager::Start()
{
MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
if (!sVolumeManager) {
return;
}
SetState(STARTING);
if (!sVolumeManager->OpenSocket()) {
// Socket open failed, try again in a second.
MessageLoopForIO::current()->
PostDelayedTask(FROM_HERE,
NewRunnableFunction(VolumeManager::Start),
1000);
}
}
/***************************************************************************/
static void
InitVolumeManagerIOThread()
{
MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
MOZ_ASSERT(!sVolumeManager);
sVolumeManager = new VolumeManager();
VolumeManager::Start();
InitVolumeServiceTestIOThread();
}
static void
ShutdownVolumeManagerIOThread()
{
MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
sVolumeManager = NULL;
}
/**************************************************************************
*
* Public API
*
* Since the VolumeManager runs in IO Thread context, we need to switch
* to IOThread context before we can do anything.
*
**************************************************************************/
void
InitVolumeManager()
{
XRE_GetIOMessageLoop()->PostTask(
FROM_HERE,
NewRunnableFunction(InitVolumeManagerIOThread));
}
void
ShutdownVolumeManager()
{
ShutdownVolumeServiceTest();
XRE_GetIOMessageLoop()->PostTask(
FROM_HERE,
NewRunnableFunction(ShutdownVolumeManagerIOThread));
}
} // system
} // mozilla