public function readAllInput()
{
$channel = $this->getIOChannel();
while ($channel->update()) {
PhutilChannel::waitForAny(array($channel));
if (!$channel->isOpenForReading()) {
break;
}
}
return $channel->read();
}
protected function waitForGitClient()
{
$io_channel = $this->getIOChannel();
// If we don't wait for the client to close the connection, `git` will
// consider it an early abort and fail. Sit around until Git is comfortable
// that it really received all the data.
while ($io_channel->isOpenForReading()) {
$io_channel->update();
$this->getErrorChannel()->flush();
PhutilChannel::waitForAny(array($io_channel));
}
}
public function run()
{
while ($this->clients) {
PhutilChannel::waitForAny($this->clients);
foreach ($this->clients as $key => $client) {
if (!$client->update()) {
// If the client has exited, remove it from the list of clients.
// We still need to process any remaining buffered I/O.
unset($this->clients[$key]);
}
while ($message = $client->read()) {
$response = $this->handleMessage($message);
if ($response) {
$client->write($response);
}
}
}
}
}
public function execute()
{
while (true) {
if ($this->exec) {
$iterator = new FutureIterator($this->exec);
$iterator->setUpdateInterval(0.05);
foreach ($iterator as $key => $future) {
if ($future === null) {
break;
}
$this->resolveFuture($key, $future);
break;
}
} else {
PhutilChannel::waitForAny(array($this->getMaster()));
}
$this->processInput();
}
}
/**
* Construct a socket channel from a socket or a socket pair.
*
* NOTE: This must be a //stream// socket from `stream_socket_client()` or
* `stream_socket_server()` or similar, not a //plain// socket from
* `socket_create()` or similar.
*
* @param socket Socket (stream socket, not plain socket). If only one
* socket is provided, it is used for reading and writing.
* @param socket? Optional write socket.
*
* @task construct
*/
public function __construct($read_socket, $write_socket = null)
{
parent::__construct();
foreach (array($read_socket, $write_socket) as $socket) {
if (!$socket) {
continue;
}
$ok = stream_set_blocking($socket, false);
if (!$ok) {
throw new Exception("Failed to set socket nonblocking!");
}
}
$this->readSocket = $read_socket;
if ($write_socket) {
$this->writeSocket = $write_socket;
} else {
$this->writeSocket = $read_socket;
$this->isSingleSocket = true;
}
}
/**
* Update one client, processing any commands it has sent us. We fully
* process all commands we've received here before returning to the main
* server loop.
*
* @param ArcanistHgClientChannel The client to update.
* @param ArcanistHgServerChannel The Mercurial server.
*
* @task server
*/
private function updateClient(ArcanistHgClientChannel $client, ArcanistHgServerChannel $hg)
{
if (!$client->update()) {
// Client has disconnected, don't bother proceeding.
return false;
}
// Read a command from the client if one is available. Note that we stop
// updating other clients or accepting new connections while processing a
// command, since there isn't much we can do with them until the server
// finishes executing this command.
$message = $client->read();
if (!$message) {
return true;
}
$this->log($client, '$ ' . $message[0] . ' ' . $message[1]);
$t_start = microtime(true);
// Forward the command to the server.
$hg->write($message);
while (true) {
PhutilChannel::waitForAny(array($client, $hg));
if (!$client->update() || !$hg->update()) {
// If either the client or server has exited, bail.
return false;
}
$response = $hg->read();
if (!$response) {
continue;
}
// Forward the response back to the client.
$client->write($response);
// If the response was on the 'r'esult channel, it indicates the end
// of the command output. We can process the next command (if any
// remain) or go back to accepting new connections and servicing
// other clients.
if ($response[0] == 'r') {
// Update the client immediately to try to get the bytes on the wire
// as quickly as possible. This gives us slightly more throughput.
$client->update();
break;
}
}
// Log the elapsed time.
$t_end = microtime(true);
$t = 1000000 * ($t_end - $t_start);
$this->log($client, pht('< %sus', number_format($t, 0)));
$this->idleSince = time();
return true;
}
public function update()
{
$this->future->isReady();
return parent::update();
}
private function agentExpect(PhutilChannel $agent, $expect, $what)
{
$message = $agent->waitForMessage();
$this->assertEqual($expect, $message, $what);
}
public function __construct(PhutilChannel $channel)
{
parent::__construct();
$this->channel = $channel;
$this->didConstruct();
}
public function setReadBufferSize($size)
{
// NOTE: We may end up using 2x the buffer size here, one inside
// ExecFuture and one inside the Channel. We could tune this eventually, but
// it should be fine for now.
parent::setReadBufferSize($size);
$this->future->setReadBufferSize($size);
return $this;
}
protected function identifyRepository()
{
// NOTE: In SVN, we need to read the first few protocol frames before we
// can determine which repository the user is trying to access. We're
// going to peek at the data on the wire to identify the repository.
$io_channel = $this->getIOChannel();
// Before the client will send us the first protocol frame, we need to send
// it a connection frame with server capabilities. To figure out the
// correct frame we're going to start `svnserve`, read the frame from it,
// send it to the client, then kill the subprocess.
// TODO: This is pretty inelegant and the protocol frame will change very
// rarely. We could cache it if we can find a reasonable way to dirty the
// cache.
$command = csprintf('svnserve -t');
$command = PhabricatorDaemon::sudoCommandAsDaemonUser($command);
$future = new ExecFuture('%C', $command);
$exec_channel = new PhutilExecChannel($future);
$exec_protocol = new DiffusionSubversionWireProtocol();
while (true) {
PhutilChannel::waitForAny(array($exec_channel));
$exec_channel->update();
$exec_message = $exec_channel->read();
if ($exec_message !== null) {
$messages = $exec_protocol->writeData($exec_message);
if ($messages) {
$message = head($messages);
$raw = $message['raw'];
// Write the greeting frame to the client.
$io_channel->write($raw);
// Kill the subprocess.
$future->resolveKill();
break;
}
}
if (!$exec_channel->isOpenForReading()) {
throw new Exception(pht('%s subprocess exited before emitting a protocol frame.', 'svnserve'));
}
}
$io_protocol = new DiffusionSubversionWireProtocol();
while (true) {
PhutilChannel::waitForAny(array($io_channel));
$io_channel->update();
$in_message = $io_channel->read();
if ($in_message !== null) {
$this->peekBuffer .= $in_message;
if (strlen($this->peekBuffer) > 1024 * 1024) {
throw new Exception(pht('Client transmitted more than 1MB of data without transmitting ' . 'a recognizable protocol frame.'));
}
$messages = $io_protocol->writeData($in_message);
if ($messages) {
$message = head($messages);
$struct = $message['structure'];
// This is the:
//
// ( version ( cap1 ... ) url ... )
//
// The `url` allows us to identify the repository.
$uri = $struct[2]['value'];
$path = $this->getPathFromSubversionURI($uri);
return $this->loadRepositoryWithPath($path, PhabricatorRepositoryType::REPOSITORY_TYPE_SVN);
}
}
if (!$io_channel->isOpenForReading()) {
throw new Exception(pht('Client closed connection before sending a complete protocol ' . 'frame.'));
}
// If the client has disconnected, kill the subprocess and bail.
if (!$io_channel->isOpenForWriting()) {
throw new Exception(pht('Client closed connection before receiving response.'));
}
}
}
public function execute()
{
$command_channel = $this->commandChannel;
$io_channel = $this->ioChannel;
$error_channel = $this->errorChannel;
if (!$command_channel) {
throw new Exception('Set a command channel before calling execute()!');
}
if (!$io_channel) {
throw new Exception('Set an IO channel before calling execute()!');
}
if (!$error_channel) {
throw new Exception('Set an error channel before calling execute()!');
}
$channels = array($command_channel, $io_channel, $error_channel);
// We want to limit the amount of data we'll hold in memory for this
// process. See T4241 for a discussion of this issue in general.
$buffer_size = 1024 * 1024;
// 1MB
$io_channel->setReadBufferSize($buffer_size);
$command_channel->setReadBufferSize($buffer_size);
// TODO: This just makes us throw away stderr after the first 1MB, but we
// don't currently have the support infrastructure to buffer it correctly.
// It's difficult to imagine this causing problems in practice, though.
$this->execFuture->getStderrSizeLimit($buffer_size);
while (true) {
PhutilChannel::waitForAny($channels);
$io_channel->update();
$command_channel->update();
$error_channel->update();
// If any channel is blocked on the other end, wait for it to flush before
// we continue reading. For example, if a user is running `git clone` on
// a 1GB repository, the underlying `git-upload-pack` may
// be able to produce data much more quickly than we can send it over
// the network. If we don't throttle the reads, we may only send a few
// MB over the I/O channel in the time it takes to read the entire 1GB off
// the command channel. That leaves us with 1GB of data in memory.
while ($command_channel->isOpen() && $io_channel->isOpenForWriting() && ($command_channel->getWriteBufferSize() >= $buffer_size || $io_channel->getWriteBufferSize() >= $buffer_size || $error_channel->getWriteBufferSize() >= $buffer_size)) {
PhutilChannel::waitForActivity(array(), $channels);
$io_channel->update();
$command_channel->update();
$error_channel->update();
}
// If the subprocess has exited and we've read everything from it,
// we're all done.
$done = !$command_channel->isOpenForReading() && $command_channel->isReadBufferEmpty();
$in_message = $io_channel->read();
if ($in_message !== null) {
$in_message = $this->willWriteData($in_message);
if ($in_message !== null) {
$command_channel->write($in_message);
}
}
$out_message = $command_channel->read();
if ($out_message !== null) {
$out_message = $this->willReadData($out_message);
if ($out_message !== null) {
$io_channel->write($out_message);
}
}
// If we have nothing left on stdin, close stdin on the subprocess.
if (!$io_channel->isOpenForReading()) {
$command_channel->closeWriteChannel();
}
if ($done) {
break;
}
// If the client has disconnected, kill the subprocess and bail.
if (!$io_channel->isOpenForWriting()) {
$this->execFuture->setStdoutSizeLimit(0)->setStderrSizeLimit(0)->setReadBufferSize(null)->resolveKill();
break;
}
}
list($err) = $this->execFuture->setStdoutSizeLimit(0)->setStderrSizeLimit(0)->setReadBufferSize(null)->resolve();
return $err;
}
