#include <assert.h>
#include <errno.h>
+#include <netinet/in.h>
#include <pthread.h>
+#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
+#include <string.h>
#include <sys/epoll.h>
#include <sys/sendfile.h>
#include <sys/socket.h>
#include <sys/types.h>
-#include <time.h>
#include <unistd.h>
#include <algorithm>
#include <map>
#include <utility>
#include <vector>
+#include "accesslog.h"
+#include "log.h"
#include "markpool.h"
+#include "metacube2.h"
#include "mutexlock.h"
#include "parse.h"
#include "server.h"
#include "state.pb.h"
#include "stream.h"
+#include "util.h"
+
+#ifndef SO_MAX_PACING_RATE
+#define SO_MAX_PACING_RATE 47
+#endif
using namespace std;
+extern AccessLogThread *access_log;
+
Server::Server()
{
pthread_mutex_init(&mutex, NULL);
- pthread_mutex_init(&queued_data_mutex, NULL);
+ pthread_mutex_init(&queued_clients_mutex, NULL);
epoll_fd = epoll_create(1024); // Size argument is ignored.
if (epoll_fd == -1) {
- perror("epoll_fd");
+ log_perror("epoll_fd");
exit(1);
}
}
Server::~Server()
{
- int ret;
- do {
- ret = close(epoll_fd);
- } while (ret == -1 && errno == EINTR);
-
- if (ret == -1) {
- perror("close(epoll_fd)");
+ for (size_t i = 0; i < streams.size(); ++i) {
+ delete streams[i];
}
+
+ safe_close(epoll_fd);
}
vector<ClientStats> Server::get_client_stats() const
void Server::do_work()
{
- for ( ;; ) {
- int nfds = epoll_wait(epoll_fd, events, EPOLL_MAX_EVENTS, EPOLL_TIMEOUT_MS);
- if (nfds == -1 && errno == EINTR) {
- if (should_stop) {
- return;
- }
- continue;
- }
- if (nfds == -1) {
- perror("epoll_wait");
+ while (!should_stop()) {
+ // Wait until there's activity on at least one of the fds,
+ // or 20 ms (about one frame at 50 fps) has elapsed.
+ //
+ // We could in theory wait forever and rely on wakeup()
+ // from add_client_deferred() and add_data_deferred(),
+ // but wakeup is a pretty expensive operation, and the
+ // two threads might end up fighting over a lock, so it's
+ // seemingly (much) more efficient to just have a timeout here.
+ int nfds = epoll_pwait(epoll_fd, events, EPOLL_MAX_EVENTS, EPOLL_TIMEOUT_MS, &sigset_without_usr1_block);
+ if (nfds == -1 && errno != EINTR) {
+ log_perror("epoll_wait");
exit(1);
}
process_queued_data();
for (int i = 0; i < nfds; ++i) {
- int fd = events[i].data.fd;
- assert(clients.count(fd) != 0);
- Client *client = &clients[fd];
+ Client *client = reinterpret_cast<Client *>(events[i].data.u64);
if (events[i].events & (EPOLLERR | EPOLLRDHUP | EPOLLHUP)) {
close_client(client);
process_client(client);
}
- for (map<string, Stream *>::iterator stream_it = streams.begin();
- stream_it != streams.end();
- ++stream_it) {
+ for (size_t i = 0; i < streams.size(); ++i) {
vector<Client *> to_process;
- swap(stream_it->second->to_process, to_process);
+ swap(streams[i]->to_process, to_process);
for (size_t i = 0; i < to_process.size(); ++i) {
process_client(to_process[i]);
}
}
-
- if (should_stop) {
- return;
- }
}
}
// We don't serialize anything queued, so empty the queues.
process_queued_data();
+ // Set all clients in a consistent state before serializing
+ // (ie., they have no remaining lost data). Otherwise, increasing
+ // the backlog could take clients into a newly valid area of the backlog,
+ // sending a stream of zeros instead of skipping the data as it should.
+ //
+ // TODO: Do this when clients are added back from serialized state instead;
+ // it would probably be less wasteful.
+ for (map<int, Client>::iterator client_it = clients.begin();
+ client_it != clients.end();
+ ++client_it) {
+ skip_lost_data(&client_it->second);
+ }
+
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());
+ for (size_t i = 0; i < streams.size(); ++i) {
+ serialized.add_streams()->MergeFrom(streams[i]->serialize());
}
return serialized;
}
void Server::add_client_deferred(int sock)
{
- MutexLock lock(&queued_data_mutex);
+ MutexLock lock(&queued_clients_mutex);
queued_add_clients.push_back(sock);
}
void Server::add_client(int sock)
{
- clients.insert(make_pair(sock, Client(sock)));
+ pair<map<int, Client>::iterator, bool> ret =
+ clients.insert(make_pair(sock, Client(sock)));
+ assert(ret.second == true); // Should not already exist.
+ Client *client_ptr = &ret.first->second;
// Start listening on data from this socket.
epoll_event ev;
ev.events = EPOLLIN | EPOLLET | EPOLLRDHUP;
- ev.data.u64 = 0; // Keep Valgrind happy.
- ev.data.fd = sock;
+ ev.data.u64 = reinterpret_cast<uint64_t>(client_ptr);
if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, sock, &ev) == -1) {
- perror("epoll_ctl(EPOLL_CTL_ADD)");
+ log_perror("epoll_ctl(EPOLL_CTL_ADD)");
exit(1);
}
- process_client(&clients[sock]);
+ process_client(client_ptr);
}
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)));
- Client *client_ptr = &clients[client.sock()];
+ Stream *stream;
+ int stream_index = lookup_stream_by_url(client.url());
+ if (stream_index == -1) {
+ assert(client.state() != Client::SENDING_DATA);
+ stream = NULL;
+ } else {
+ stream = streams[stream_index];
+ }
+ pair<map<int, Client>::iterator, bool> ret =
+ clients.insert(make_pair(client.sock(), Client(client, stream)));
+ assert(ret.second == true); // Should not already exist.
+ Client *client_ptr = &ret.first->second;
// Start listening on data from this socket.
epoll_event ev;
// the sleeping array again soon.
ev.events = EPOLLOUT | EPOLLET | EPOLLRDHUP;
}
- ev.data.u64 = 0; // Keep Valgrind happy.
- ev.data.fd = client.sock();
+ ev.data.u64 = reinterpret_cast<uint64_t>(client_ptr);
if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, client.sock(), &ev) == -1) {
- perror("epoll_ctl(EPOLL_CTL_ADD)");
+ log_perror("epoll_ctl(EPOLL_CTL_ADD)");
exit(1);
}
- if (client_ptr->state == Client::SENDING_DATA &&
- client_ptr->bytes_sent == client_ptr->stream->bytes_received) {
+ if (client_ptr->state == Client::WAITING_FOR_KEYFRAME ||
+ (client_ptr->state == Client::SENDING_DATA &&
+ client_ptr->stream_pos == client_ptr->stream->bytes_received)) {
client_ptr->stream->put_client_to_sleep(client_ptr);
} else {
process_client(client_ptr);
}
}
-void Server::add_stream(const string &stream_id, size_t backlog_size)
+int Server::lookup_stream_by_url(const std::string &url) const
+{
+ map<string, int>::const_iterator url_it = url_map.find(url);
+ if (url_it == url_map.end()) {
+ return -1;
+ }
+ return url_it->second;
+}
+
+int Server::add_stream(const string &url, size_t backlog_size, Stream::Encoding encoding)
{
MutexLock lock(&mutex);
- streams.insert(make_pair(stream_id, new Stream(stream_id, backlog_size)));
+ url_map.insert(make_pair(url, streams.size()));
+ streams.push_back(new Stream(url, backlog_size, encoding));
+ return streams.size() - 1;
}
-void Server::add_stream_from_serialized(const StreamProto &stream)
+int Server::add_stream_from_serialized(const StreamProto &stream, int data_fd)
{
MutexLock lock(&mutex);
- streams.insert(make_pair(stream.stream_id(), new Stream(stream)));
+ url_map.insert(make_pair(stream.url(), streams.size()));
+ streams.push_back(new Stream(stream, data_fd));
+ return streams.size() - 1;
}
-void Server::set_header(const string &stream_id, const string &header)
+void Server::set_backlog_size(int stream_index, size_t new_size)
{
MutexLock lock(&mutex);
- find_stream(stream_id)->header = header;
+ assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
+ streams[stream_index]->set_backlog_size(new_size);
+}
+
+void Server::set_encoding(int stream_index, Stream::Encoding encoding)
+{
+ MutexLock lock(&mutex);
+ assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
+ streams[stream_index]->encoding = encoding;
+}
+
+void Server::set_header(int stream_index, const string &http_header, const string &stream_header)
+{
+ MutexLock lock(&mutex);
+ assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
+ streams[stream_index]->http_header = http_header;
+ streams[stream_index]->stream_header = stream_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.
client_it != clients.end();
++client_it) {
Client *client = &client_it->second;
- if (client->state == Client::SENDING_DATA &&
- client->bytes_sent == 0) {
+ if (client->state == Client::WAITING_FOR_KEYFRAME ||
+ (client->state == Client::SENDING_DATA &&
+ client->stream_pos == 0)) {
construct_header(client);
}
}
}
-void Server::set_mark_pool(const std::string &stream_id, MarkPool *mark_pool)
+void Server::set_mark_pool(int stream_index, MarkPool *mark_pool)
{
MutexLock lock(&mutex);
assert(clients.empty());
- find_stream(stream_id)->mark_pool = mark_pool;
+ assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
+ streams[stream_index]->mark_pool = mark_pool;
}
-void Server::add_data_deferred(const string &stream_id, const char *data, size_t bytes)
+void Server::set_pacing_rate(int stream_index, uint32_t pacing_rate)
{
- MutexLock lock(&queued_data_mutex);
- queued_data[stream_id].append(string(data, data + bytes));
+ MutexLock lock(&mutex);
+ assert(clients.empty());
+ assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
+ streams[stream_index]->pacing_rate = pacing_rate;
}
-void Server::add_data(const string &stream_id, const char *data, ssize_t bytes)
+void Server::add_data_deferred(int stream_index, const char *data, size_t bytes, StreamStartSuitability suitable_for_stream_start)
{
- Stream *stream = find_stream(stream_id);
- size_t pos = stream->bytes_received % stream->backlog_size;
- stream->bytes_received += bytes;
-
- if (pos + bytes > stream->backlog_size) {
- ssize_t to_copy = stream->backlog_size - pos;
- while (to_copy > 0) {
- int ret = pwrite(stream->data_fd, data, to_copy, pos);
- if (ret == -1 && errno == EINTR) {
- continue;
- }
- if (ret == -1) {
- perror("pwrite");
- // Dazed and confused, but trying to continue...
- break;
- }
- pos += ret;
- data += ret;
- to_copy -= ret;
- bytes -= ret;
- }
- pos = 0;
- }
-
- while (bytes > 0) {
- int ret = pwrite(stream->data_fd, data, bytes, pos);
- if (ret == -1 && errno == EINTR) {
- continue;
- }
- if (ret == -1) {
- perror("pwrite");
- // Dazed and confused, but trying to continue...
- break;
- }
- pos += ret;
- data += ret;
- bytes -= ret;
- }
-
- stream->wake_up_all_clients();
+ assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
+ streams[stream_index]->add_data_deferred(data, bytes, suitable_for_stream_start);
}
// See the .h file for postconditions after this function.
return;
}
if (ret == -1) {
- perror("read");
+ log_perror("read");
close_client(client);
return;
}
switch (status) {
case RP_OUT_OF_SPACE:
- fprintf(stderr, "WARNING: fd %d sent overlong request!\n", client->sock);
+ log(WARNING, "[%s] Client sent overlong request!", client->remote_addr.c_str());
close_client(client);
return;
case RP_NOT_FINISHED_YET:
// See if there's more data for us.
goto read_request_again;
case RP_EXTRA_DATA:
- fprintf(stderr, "WARNING: fd %d had junk data after request!\n", client->sock);
+ log(WARNING, "[%s] Junk data after request!", client->remote_addr.c_str());
close_client(client);
return;
case RP_FINISHED:
if (ret == -1) {
// Error! Postcondition #1.
- perror("write");
+ log_perror("write");
close_client(client);
return;
}
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.
+ // Start sending from the first keyframe we get. In other
+ // words, we won't send any of the backlog, but we'll start
+ // sending immediately as we get the next keyframe block.
// This is postcondition #3.
- client->state = Client::SENDING_DATA;
- client->bytes_sent = client->stream->bytes_received;
+ if (client->stream_pos == size_t(-2)) {
+ client->stream_pos = std::min<size_t>(
+ client->stream->bytes_received - client->stream->backlog_size,
+ 0);
+ client->state = Client::SENDING_DATA;
+ } else {
+ // client->stream_pos should be -1, but it might not be,
+ // if we have clients from an older version.
+ client->stream_pos = client->stream->bytes_received;
+ client->state = Client::WAITING_FOR_KEYFRAME;
+ }
client->stream->put_client_to_sleep(client);
return;
}
+ case Client::WAITING_FOR_KEYFRAME: {
+ Stream *stream = client->stream;
+ if (ssize_t(client->stream_pos) > stream->last_suitable_starting_point) {
+ // We haven't received a keyframe since this stream started waiting,
+ // so keep on waiting for one.
+ // This is postcondition #3.
+ stream->put_client_to_sleep(client);
+ return;
+ }
+ client->stream_pos = stream->last_suitable_starting_point;
+ client->state = Client::SENDING_DATA;
+ // Fall through.
+ }
case Client::SENDING_DATA: {
-sending_data_again:
- // 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.
+ skip_lost_data(client);
Stream *stream = client->stream;
- size_t bytes_to_send = stream->bytes_received - client->bytes_sent;
+
+sending_data_again:
+ size_t bytes_to_send = stream->bytes_received - client->stream_pos;
+ assert(bytes_to_send <= stream->backlog_size);
if (bytes_to_send == 0) {
return;
}
- if (bytes_to_send > stream->backlog_size) {
- fprintf(stderr, "WARNING: fd %d lost %lld bytes, maybe too slow connection\n",
- client->sock,
- (long long int)(bytes_to_send - stream->backlog_size));
- client->bytes_sent = stream->bytes_received - stream->backlog_size;
- bytes_to_send = stream->backlog_size;
- }
// See if we need to split across the circular buffer.
bool more_data = false;
- if ((client->bytes_sent % stream->backlog_size) + bytes_to_send > stream->backlog_size) {
- bytes_to_send = stream->backlog_size - (client->bytes_sent % stream->backlog_size);
+ if ((client->stream_pos % stream->backlog_size) + bytes_to_send > stream->backlog_size) {
+ bytes_to_send = stream->backlog_size - (client->stream_pos % stream->backlog_size);
more_data = true;
}
ssize_t ret;
do {
- loff_t offset = client->bytes_sent % stream->backlog_size;
+ off_t offset = client->stream_pos % stream->backlog_size;
ret = sendfile(client->sock, stream->data_fd, &offset, bytes_to_send);
} while (ret == -1 && errno == EINTR);
}
if (ret == -1) {
// Error, close; postcondition #1.
- perror("sendfile");
+ log_perror("sendfile");
close_client(client);
return;
}
+ client->stream_pos += ret;
client->bytes_sent += ret;
- if (client->bytes_sent == stream->bytes_received) {
+ if (client->stream_pos == stream->bytes_received) {
// We don't have any more data for this client, so put it to sleep.
// This is postcondition #3.
stream->put_client_to_sleep(client);
- } else if (more_data) {
+ } else if (more_data && size_t(ret) == bytes_to_send) {
goto sending_data_again;
}
break;
}
}
+// 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.
+void Server::skip_lost_data(Client *client)
+{
+ Stream *stream = client->stream;
+ size_t bytes_to_send = stream->bytes_received - client->stream_pos;
+ if (bytes_to_send > stream->backlog_size) {
+ size_t bytes_lost = bytes_to_send - stream->backlog_size;
+ client->stream_pos = stream->bytes_received - stream->backlog_size;
+ client->bytes_lost += bytes_lost;
+ ++client->num_loss_events;
+
+ double loss_fraction = double(client->bytes_lost) / double(client->bytes_lost + client->bytes_sent);
+ log(WARNING, "[%s] Client lost %lld bytes (total loss: %.2f%%), maybe too slow connection",
+ client->remote_addr.c_str(),
+ (long long int)(bytes_lost),
+ 100.0 * loss_fraction);
+ }
+}
+
int Server::parse_request(Client *client)
{
vector<string> lines = split_lines(client->request);
if (request_tokens[0] != "GET") {
return 400; // Should maybe be 405 instead?
}
- if (streams.count(request_tokens[1]) == 0) {
+
+ string url = request_tokens[1];
+ if (url.find("?backlog") == url.size() - 8) {
+ client->stream_pos = -2;
+ url = url.substr(0, url.size() - 8);
+ } else {
+ client->stream_pos = -1;
+ }
+
+ map<string, int>::const_iterator url_map_it = url_map.find(url);
+ if (url_map_it == url_map.end()) {
return 404; // Not found.
}
- client->stream_id = request_tokens[1];
- client->stream = find_stream(client->stream_id);
+ client->url = request_tokens[1];
+ client->stream = streams[url_map_it->second];
if (client->stream->mark_pool != NULL) {
client->fwmark = client->stream->mark_pool->get_mark();
} else {
}
if (setsockopt(client->sock, SOL_SOCKET, SO_MARK, &client->fwmark, sizeof(client->fwmark)) == -1) {
if (client->fwmark != 0) {
- perror("setsockopt(SO_MARK)");
+ log_perror("setsockopt(SO_MARK)");
+ }
+ }
+ if (setsockopt(client->sock, SOL_SOCKET, SO_MAX_PACING_RATE, &client->stream->pacing_rate, sizeof(client->stream->pacing_rate)) == -1) {
+ if (client->stream->pacing_rate != ~0U) {
+ log_perror("setsockopt(SO_MAX_PACING_RATE)");
}
}
client->request.clear();
void Server::construct_header(Client *client)
{
- client->header_or_error = find_stream(client->stream_id)->header;
+ Stream *stream = client->stream;
+ if (stream->encoding == Stream::STREAM_ENCODING_RAW) {
+ client->header_or_error = stream->http_header +
+ "\r\n" +
+ stream->stream_header;
+ } else if (stream->encoding == Stream::STREAM_ENCODING_METACUBE) {
+ client->header_or_error = stream->http_header +
+ "Content-encoding: metacube\r\n" +
+ "\r\n";
+ if (!stream->stream_header.empty()) {
+ metacube2_block_header hdr;
+ memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
+ hdr.size = htonl(stream->stream_header.size());
+ hdr.flags = htons(METACUBE_FLAGS_HEADER);
+ hdr.csum = htons(metacube2_compute_crc(&hdr));
+ client->header_or_error.append(
+ string(reinterpret_cast<char *>(&hdr), sizeof(hdr)));
+ }
+ client->header_or_error.append(stream->stream_header);
+ } else {
+ assert(false);
+ }
// 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;
+ ev.data.u64 = reinterpret_cast<uint64_t>(client);
if (epoll_ctl(epoll_fd, EPOLL_CTL_MOD, client->sock, &ev) == -1) {
- perror("epoll_ctl(EPOLL_CTL_MOD)");
+ log_perror("epoll_ctl(EPOLL_CTL_MOD)");
exit(1);
}
}
epoll_event ev;
ev.events = EPOLLOUT | EPOLLET | EPOLLRDHUP;
- ev.data.u64 = 0; // Keep Valgrind happy.
- ev.data.fd = client->sock;
+ ev.data.u64 = reinterpret_cast<uint64_t>(client);
if (epoll_ctl(epoll_fd, EPOLL_CTL_MOD, client->sock, &ev) == -1) {
- perror("epoll_ctl(EPOLL_CTL_MOD)");
+ log_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)");
+ log_perror("epoll_ctl(EPOLL_CTL_DEL)");
exit(1);
}
}
}
- // Bye-bye!
- int ret;
- do {
- ret = close(client->sock);
- } while (ret == -1 && errno == EINTR);
+ // Log to access_log.
+ access_log->write(client->get_stats());
- if (ret == -1) {
- perror("close");
- }
+ // Bye-bye!
+ safe_close(client->sock);
clients.erase(client->sock);
}
-Stream *Server::find_stream(const string &stream_id)
-{
- map<string, Stream *>::iterator it = streams.find(stream_id);
- assert(it != streams.end());
- return it->second;
-}
-
void Server::process_queued_data()
{
- MutexLock lock(&queued_data_mutex);
+ {
+ MutexLock lock(&queued_clients_mutex);
- for (size_t i = 0; i < queued_add_clients.size(); ++i) {
- add_client(queued_add_clients[i]);
+ for (size_t i = 0; i < queued_add_clients.size(); ++i) {
+ add_client(queued_add_clients[i]);
+ }
+ queued_add_clients.clear();
}
- queued_add_clients.clear();
-
- for (map<string, string>::iterator queued_it = queued_data.begin();
- queued_it != queued_data.end();
- ++queued_it) {
- add_data(queued_it->first, queued_it->second.data(), queued_it->second.size());
+
+ for (size_t i = 0; i < streams.size(); ++i) {
+ streams[i]->process_queued_data();
}
- queued_data.clear();
}