X-Git-Url: https://git.sesse.net/?p=cubemap;a=blobdiff_plain;f=server.cpp;h=54e6b5e804d9959632b1ef70df6a53fee7f52fac;hp=31e5c0a31da327bc80499c543bbb4dee932b74bb;hb=43be6b6e71a38923e923f33daa1fd1172bcdd539;hpb=97bdb597d4847308ce9d6982505b56a3a09e930b

diff --git a/server.cpp b/server.cpp
index 31e5c0a..54e6b5e 100644
--- a/server.cpp
+++ b/server.cpp
@@ -13,13 +13,84 @@
 #include <vector>
 #include <string>
 #include <map>
+#include <algorithm>
 
 #include "metacube.h"
 #include "server.h"
 #include "mutexlock.h"
+#include "parse.h"
+#include "state.pb.h"
 
 using namespace std;
 
+Client::Client(int sock)
+	: sock(sock),
+	  state(Client::READING_REQUEST),
+	  stream(NULL),
+	  header_or_error_bytes_sent(0),
+	  bytes_sent(0)
+{
+	request.reserve(1024);
+}
+	
+Client::Client(const ClientProto &serialized, Stream *stream)
+	: sock(serialized.sock()),
+	  state(State(serialized.state())),
+	  request(serialized.request()),
+	  stream_id(serialized.stream_id()),
+	  stream(stream),
+	  header_or_error(serialized.header_or_error()),
+	  header_or_error_bytes_sent(serialized.header_or_error_bytes_sent()),
+	  bytes_sent(serialized.bytes_sent())
+{
+}
+
+ClientProto Client::serialize() const
+{
+	ClientProto serialized;
+	serialized.set_sock(sock);
+	serialized.set_state(state);
+	serialized.set_request(request);
+	serialized.set_stream_id(stream_id);
+	serialized.set_header_or_error(header_or_error);
+	serialized.set_header_or_error_bytes_sent(serialized.header_or_error_bytes_sent());
+	serialized.set_bytes_sent(bytes_sent);
+	return serialized;
+}
+
+Stream::Stream(const string &stream_id)
+	: stream_id(stream_id),
+	  data(new char[BACKLOG_SIZE]),
+	  data_size(0)
+{
+	memset(data, 0, BACKLOG_SIZE);
+}
+
+Stream::~Stream()
+{
+	delete[] data;
+}
+
+Stream::Stream(const StreamProto &serialized)
+	: stream_id(serialized.stream_id()),
+	  header(serialized.header()),
+	  data(new char[BACKLOG_SIZE]),
+	  data_size(serialized.data_size())
+{
+	assert(serialized.data().size() == BACKLOG_SIZE);
+	memcpy(data, serialized.data().data(), BACKLOG_SIZE);
+}
+
+StreamProto Stream::serialize() const
+{
+	StreamProto serialized;
+	serialized.set_header(header);
+	serialized.set_data(string(data, data + BACKLOG_SIZE));
+	serialized.set_data_size(data_size);
+	serialized.set_stream_id(stream_id);
+	return serialized;
+}
+
 Server::Server()
 {
 	pthread_mutex_init(&mutex, NULL);
@@ -31,10 +102,40 @@ Server::Server()
 	}
 }
 
+Server::~Server()
+{
+	int ret;
+	do {
+		ret = close(epoll_fd);
+	} while (ret == -1 && errno == EINTR);
+
+	if (ret == -1) {
+		perror("close(epoll_fd)");
+	}
+}
+
 void Server::run()
 {
-	pthread_t thread;
-	pthread_create(&thread, NULL, Server::do_work_thunk, this);
+	should_stop = false;
+	
+	// Joinable is already the default, but it's good to be certain.
+	pthread_attr_t attr;
+	pthread_attr_init(&attr);
+	pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
+	pthread_create(&worker_thread, &attr, Server::do_work_thunk, this);
+}
+	
+void Server::stop()
+{
+	{
+		MutexLock lock(&mutex);
+		should_stop = true;
+	}
+
+	if (pthread_join(worker_thread, NULL) == -1) {
+		perror("pthread_join");
+		exit(1);
+	}
 }
 
 void *Server::do_work_thunk(void *arg)
@@ -47,44 +148,436 @@ void *Server::do_work_thunk(void *arg)
 void Server::do_work()
 {
 	for ( ;; ) {
-		MutexLock lock(&mutex);
-		printf("server thread running\n");
-		sleep(1);
+		int nfds = epoll_wait(epoll_fd, events, EPOLL_MAX_EVENTS, EPOLL_TIMEOUT_MS);
+		if (nfds == -1 && errno == EINTR) {
+			continue;
+		}
+		if (nfds == -1) {
+			perror("epoll_wait");
+			exit(1);
+		}
+
+		MutexLock lock(&mutex);  // We release the mutex between iterations.
+	
+		if (should_stop) {
+			return;
+		}
+	
+		for (int i = 0; i < nfds; ++i) {
+			int fd = events[i].data.fd;
+			assert(clients.count(fd) != 0);
+			Client *client = &clients[fd];
+
+			if (events[i].events & (EPOLLERR | EPOLLRDHUP | EPOLLHUP)) {
+				close_client(client);
+				continue;
+			}
+
+			process_client(client);
+		}
 	}
 }
-	
+
+CubemapStateProto Server::serialize() const
+{
+	CubemapStateProto serialized;
+	for (map<int, Client>::const_iterator client_it = clients.begin();
+	     client_it != clients.end();
+	     ++client_it) {
+		serialized.add_clients()->MergeFrom(client_it->second.serialize());
+	}
+	for (map<string, Stream *>::const_iterator stream_it = streams.begin();
+	     stream_it != streams.end();
+	     ++stream_it) {
+		serialized.add_streams()->MergeFrom(stream_it->second->serialize());
+	}
+	return serialized;
+}
+
 void Server::add_client(int sock)
 {
 	MutexLock lock(&mutex);
-	Client new_client;
-	new_client.state = Client::READING_REQUEST;
-	new_client.header_bytes_sent = 0;
-	new_client.bytes_sent = 0;
-
-	clients.insert(make_pair(sock, new_client));
+	clients.insert(make_pair(sock, Client(sock)));
 
 	// Start listening on data from this socket.
 	epoll_event ev;
-	ev.events = EPOLLIN;
+	ev.events = EPOLLIN | EPOLLRDHUP;
+	ev.data.u64 = 0;  // Keep Valgrind happy.
 	ev.data.fd = sock;
 	if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, sock, &ev) == -1) {
 		perror("epoll_ctl(EPOLL_CTL_ADD)");
 		exit(1);
 	}
 }
-	
+
+void Server::add_client_from_serialized(const ClientProto &client)
+{
+	MutexLock lock(&mutex);
+	Stream *stream = find_stream(client.stream_id());
+	clients.insert(make_pair(client.sock(), Client(client, stream)));
+
+	// Start listening on data from this socket.
+	epoll_event ev;
+	if (client.state() == Client::READING_REQUEST) {
+		ev.events = EPOLLIN | EPOLLET | EPOLLRDHUP;
+	} else {
+		// If we don't have more data for this client, we'll be putting it into
+		// the sleeping array again soon.
+		ev.events = EPOLLOUT | EPOLLET | EPOLLRDHUP;
+	}
+	ev.data.u64 = 0;  // Keep Valgrind happy.
+	ev.data.fd = client.sock();
+	if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, client.sock(), &ev) == -1) {
+		perror("epoll_ctl(EPOLL_CTL_ADD)");
+		exit(1);
+	}
+
+	process_client(&clients[client.sock()]);
+}
+
 void Server::add_stream(const string &stream_id)
 {
-	// TODO
+	MutexLock lock(&mutex);
+	streams.insert(make_pair(stream_id, new Stream(stream_id)));
+}
+
+void Server::add_stream_from_serialized(const StreamProto &stream)
+{
+	MutexLock lock(&mutex);
+	streams.insert(make_pair(stream.stream_id(), new Stream(stream)));
 }
 	
 void Server::set_header(const string &stream_id, const string &header)
 {
-	// TODO
-	printf("got header! %lu bytes\n", header.size());
+	MutexLock lock(&mutex);
+	find_stream(stream_id)->header = header;
+
+	// If there are clients we haven't sent anything to yet, we should give
+	// them the header, so push back into the SENDING_HEADER state.
+	for (map<int, Client>::iterator client_it = clients.begin();
+	     client_it != clients.end();
+	     ++client_it) {
+		Client *client = &client_it->second;
+		if (client->state == Client::SENDING_DATA &&
+		    client->bytes_sent == 0) {
+			construct_header(client);
+		}
+	}
 }
 	
 void Server::add_data(const string &stream_id, const char *data, size_t bytes)
 {
-	// TODO
+	if (bytes == 0) {
+		return;
+	}
+
+	MutexLock lock(&mutex);
+	Stream *stream = find_stream(stream_id);
+	size_t pos = stream->data_size % BACKLOG_SIZE;
+	stream->data_size += bytes;
+
+	if (pos + bytes > BACKLOG_SIZE) {
+		size_t to_copy = BACKLOG_SIZE - pos;
+		memcpy(stream->data + pos, data, to_copy);
+		data += to_copy;
+		bytes -= to_copy;
+		pos = 0;
+	}
+
+	memcpy(stream->data + pos, data, bytes);
+	wake_up_all_clients();
+}
+
+// See the .h file for postconditions after this function.	
+void Server::process_client(Client *client)
+{
+	switch (client->state) {
+	case Client::READING_REQUEST: {
+read_request_again:
+		// Try to read more of the request.
+		char buf[1024];
+		int ret;
+		do {
+			ret = read(client->sock, buf, sizeof(buf));
+		} while (ret == -1 && errno == EINTR);
+
+		if (ret == -1 && errno == EAGAIN) {
+			// No more data right now. Nothing to do.
+			// This is postcondition #2.
+			return;
+		}
+		if (ret == -1) {
+			perror("read");
+			close_client(client);
+			return;
+		}
+		if (ret == 0) {
+			// OK, the socket is closed.
+			close_client(client);
+			return;
+		}
+
+		// Guard against overlong requests gobbling up all of our space.
+		if (client->request.size() + ret > MAX_CLIENT_REQUEST) {
+			fprintf(stderr, "WARNING: fd %d sent overlong request!\n", client->sock);
+			close_client(client);
+			return;
+		}	
+
+		// See if we have \r\n\r\n anywhere in the request. We start three bytes
+		// before what we just appended, in case we just got the final character.
+		size_t existing_req_bytes = client->request.size();
+		client->request.append(string(buf, buf + ret));
+	
+		size_t start_at = (existing_req_bytes >= 3 ? existing_req_bytes - 3 : 0);
+		const char *ptr = reinterpret_cast<char *>(
+			memmem(client->request.data() + start_at, client->request.size() - start_at,
+			       "\r\n\r\n", 4));
+		if (ptr == NULL) {
+			// OK, we don't have the entire header yet. Fine; we'll get it later.
+			// See if there's more data for us.
+			goto read_request_again;
+		}
+
+		if (ptr != client->request.data() + client->request.size() - 4) {
+			fprintf(stderr, "WARNING: fd %d had junk data after request!\n", client->sock);
+			close_client(client);
+			return;
+		}
+
+		int error_code = parse_request(client);
+		if (error_code == 200) {
+			construct_header(client);
+		} else {
+			construct_error(client, error_code);
+		}
+
+		// We've changed states, so fall through.
+		assert(client->state == Client::SENDING_ERROR ||
+		       client->state == Client::SENDING_HEADER);
+	}
+	case Client::SENDING_ERROR:
+	case Client::SENDING_HEADER: {
+sending_header_or_error_again:
+		int ret;
+		do {
+			ret = write(client->sock,
+		                    client->header_or_error.data() + client->header_or_error_bytes_sent,
+				    client->header_or_error.size() - client->header_or_error_bytes_sent);
+		} while (ret == -1 && errno == EINTR);
+
+		if (ret == -1 && errno == EAGAIN) {
+			// We're out of socket space, so now we're at the “low edge” of epoll's
+			// edge triggering. epoll will tell us when there is more room, so for now,
+			// just return.
+			// This is postcondition #4.
+			return;
+		}
+
+		if (ret == -1) {
+			// Error! Postcondition #1.
+			perror("write");
+			close_client(client);
+			return;
+		}
+		
+		client->header_or_error_bytes_sent += ret;
+		assert(client->header_or_error_bytes_sent <= client->header_or_error.size());
+
+		if (client->header_or_error_bytes_sent < client->header_or_error.size()) {
+			// We haven't sent all yet. Fine; go another round.
+			goto sending_header_or_error_again;
+		}
+
+		// We're done sending the header or error! Clear it to release some memory.
+		client->header_or_error.clear();
+
+		if (client->state == Client::SENDING_ERROR) {
+			// We're done sending the error, so now close.	
+			// This is postcondition #1.
+			close_client(client);
+			return;
+		}
+
+		// Start sending from the end. In other words, we won't send any of the backlog,
+		// but we'll start sending immediately as we get data.
+		// This is postcondition #3.
+		client->state = Client::SENDING_DATA;
+		client->bytes_sent = client->stream->data_size;
+		sleeping_clients.push_back(client);
+		return;
+	}
+	case Client::SENDING_DATA: {
+		// See if there's some data we've lost. Ideally, we should drop to a block boundary,
+		// but resync will be the mux's problem.
+		const Stream *stream = client->stream;
+		size_t bytes_to_send = stream->data_size - client->bytes_sent;
+		if (bytes_to_send > BACKLOG_SIZE) {
+			fprintf(stderr, "WARNING: fd %d lost %lld bytes, maybe too slow connection\n",
+			        client->sock,
+			        (long long int)(bytes_to_send - BACKLOG_SIZE));
+			client->bytes_sent = stream->data_size - BACKLOG_SIZE;
+			bytes_to_send = BACKLOG_SIZE;
+		}
+
+		// See if we need to split across the circular buffer.
+		ssize_t ret;
+		if ((client->bytes_sent % BACKLOG_SIZE) + bytes_to_send > BACKLOG_SIZE) {
+			size_t bytes_first_part = BACKLOG_SIZE - (client->bytes_sent % BACKLOG_SIZE);
+
+			iovec iov[2];
+			iov[0].iov_base = const_cast<char *>(stream->data + (client->bytes_sent % BACKLOG_SIZE));
+			iov[0].iov_len = bytes_first_part;
+
+			iov[1].iov_base = const_cast<char *>(stream->data);
+			iov[1].iov_len = bytes_to_send - bytes_first_part;
+
+			do {
+				ret = writev(client->sock, iov, 2);
+			} while (ret == -1 && errno == EINTR);
+		} else {
+			do {
+				ret = write(client->sock,
+					    stream->data + (client->bytes_sent % BACKLOG_SIZE),
+					    bytes_to_send);
+			} while (ret == -1 && errno == EINTR);
+		}
+		if (ret == -1 && errno == EAGAIN) {
+			// We're out of socket space, so return; epoll will wake us up
+			// when there is more room.
+			// This is postcondition #4.
+			return;
+		}
+		if (ret == -1) {
+			// Error, close; postcondition #1.
+			perror("write/writev");
+			close_client(client);
+			return;
+		}
+		client->bytes_sent += ret;
+
+		if (client->bytes_sent == stream->data_size) {
+			// We don't have any more data for this client, so put it to sleep.
+			// This is postcondition #3.
+			put_client_to_sleep(client);
+		} else {
+			// XXX: Do we need to go another round here to explicitly
+			// get the EAGAIN?
+		}
+		break;
+	}
+	default:
+		assert(false);
+	}
+}
+
+int Server::parse_request(Client *client)
+{
+	vector<string> lines = split_lines(client->request);
+	if (lines.empty()) {
+		return 400;  // Bad request (empty).
+	}
+
+	vector<string> request_tokens = split_tokens(lines[0]);
+	if (request_tokens.size() < 2) {
+		return 400;  // Bad request (empty).
+	}
+	if (request_tokens[0] != "GET") {
+		return 400;  // Should maybe be 405 instead?
+	}
+	if (streams.count(request_tokens[1]) == 0) {
+		return 404;  // Not found.
+	}
+
+	client->stream_id = request_tokens[1];
+	client->stream = find_stream(client->stream_id);
+	client->request.clear();
+
+	return 200;  // OK!
+}
+
+void Server::construct_header(Client *client)
+{
+	client->header_or_error = "HTTP/1.0 200 OK\r\nContent-type: video/x-flv\r\nCache-Control: no-cache\r\n\r\n" +
+		find_stream(client->stream_id)->header;
+
+	// Switch states.
+	client->state = Client::SENDING_HEADER;
+
+	epoll_event ev;
+	ev.events = EPOLLOUT | EPOLLET | EPOLLRDHUP;
+	ev.data.u64 = 0;  // Keep Valgrind happy.
+	ev.data.fd = client->sock;
+
+	if (epoll_ctl(epoll_fd, EPOLL_CTL_MOD, client->sock, &ev) == -1) {
+		perror("epoll_ctl(EPOLL_CTL_MOD)");
+		exit(1);
+	}
+}
+	
+void Server::construct_error(Client *client, int error_code)
+{
+	char error[256];
+	snprintf(error, 256, "HTTP/1.0 %d Error\r\nContent-type: text/plain\r\n\r\nSomething went wrong. Sorry.\r\n",
+		error_code);
+	client->header_or_error = error;
+
+	// Switch states.
+	client->state = Client::SENDING_ERROR;
+
+	epoll_event ev;
+	ev.events = EPOLLOUT | EPOLLET | EPOLLRDHUP;
+	ev.data.u64 = 0;  // Keep Valgrind happy.
+	ev.data.fd = client->sock;
+
+	if (epoll_ctl(epoll_fd, EPOLL_CTL_MOD, client->sock, &ev) == -1) {
+		perror("epoll_ctl(EPOLL_CTL_MOD)");
+		exit(1);
+	}
+}
+	
+void Server::close_client(Client *client)
+{
+	if (epoll_ctl(epoll_fd, EPOLL_CTL_DEL, client->sock, NULL) == -1) {
+		perror("epoll_ctl(EPOLL_CTL_DEL)");
+		exit(1);
+	}
+
+	// This client could be sleeping, so we'll need to fix that. (Argh, O(n).)
+	vector<Client *>::iterator new_end =
+		remove(sleeping_clients.begin(), sleeping_clients.end(), client);
+	sleeping_clients.erase(new_end, sleeping_clients.end());
+	
+	// Bye-bye!
+	int ret;
+	do {
+		ret = close(client->sock);
+	} while (ret == -1 && errno == EINTR);
+
+	if (ret == -1) {
+		perror("close");
+	}
+
+	clients.erase(client->sock);
+}
+	
+void Server::put_client_to_sleep(Client *client)
+{
+	sleeping_clients.push_back(client);
+}
+
+void Server::wake_up_all_clients()
+{
+	vector<Client *> to_process;
+	swap(sleeping_clients, to_process);
+	for (unsigned i = 0; i < to_process.size(); ++i) {
+		process_client(to_process[i]);
+	}
+}
+	
+Stream *Server::find_stream(const string &stream_id)
+{
+	map<string, Stream *>::iterator it = streams.find(stream_id);
+	assert(it != streams.end());
+	return it->second;
 }