#ifndef _SERVER_H
#define _SERVER_H 1
+#include <stddef.h>
#include <stdint.h>
-#include <pthread.h>
#include <sys/epoll.h>
+#include <sys/types.h>
#include <time.h>
+#include <memory>
+#include <mutex>
+#include <queue>
#include <string>
-#include <map>
+#include <unordered_map>
#include <vector>
+#include "tlse.h"
+
+#include "client.h"
+#include "stream.h"
#include "thread.h"
-#define BACKLOG_SIZE 1048576
+class Acceptor;
+class ClientProto;
+struct Stream;
+
#define EPOLL_MAX_EVENTS 8192
#define EPOLL_TIMEOUT_MS 20
#define MAX_CLIENT_REQUEST 16384
+#define REQUEST_READ_TIMEOUT_SEC 60
-class ClientProto;
class CubemapStateProto;
-class MarkPool;
-class Stream;
class StreamProto;
+class HLSZombieProto;
-// Digested statistics for writing to logs etc.
-struct ClientStats {
- std::string stream_id;
+// See Server::hls_zombies, below.
+struct HLSZombie {
std::string remote_addr;
- time_t connect_time;
- size_t bytes_sent;
-};
-
-struct Client {
- Client() {}
- Client(int sock);
-
- // Serialization/deserialization.
- Client(const ClientProto &serialized, Stream *stream);
- ClientProto serialize() const;
-
- ClientStats get_stats() const;
-
- // The file descriptor associated with this socket.
- int sock;
-
- // The fwmark associated with this socket (or 0).
- int fwmark;
-
- // Some information only used for logging.
- std::string remote_addr;
- time_t connect_time;
-
- enum State { READING_REQUEST, SENDING_HEADER, SENDING_DATA, SENDING_ERROR };
- State state;
-
- // The HTTP request, as sent by the client. If we are in READING_REQUEST,
- // this might not be finished.
- std::string request;
-
- // What stream we're connecting to; parsed from <request>.
- // Not relevant for READING_REQUEST.
- std::string stream_id;
- Stream *stream;
-
- // The header we want to send. This is nominally a copy of Stream::header,
- // but since that might change on reconnects etc., we keep a local copy here.
- // Only relevant for SENDING_HEADER or SENDING_ERROR; blank otherwise.
- std::string header_or_error;
-
- // Number of bytes we've sent of the header. Only relevant for SENDING_HEADER
- // or SENDING_ERROR.
- size_t header_or_error_bytes_sent;
-
- // Number of bytes we've sent of data. Only relevant for SENDING_DATA.
- size_t bytes_sent;
-};
-
-struct Stream {
- Stream(const std::string &stream_id);
- ~Stream();
-
- // Serialization/deserialization.
- Stream(const StreamProto &serialized);
- StreamProto serialize();
-
- std::string stream_id;
-
- // The HTTP response header, plus the video stream header (if any).
- std::string header;
-
- // The stream data itself, stored in a circular buffer.q
- //
- // We store our data in a file, so that we can send the data to the
- // kernel only once (with write()). We then use sendfile() for each
- // client, which effectively zero-copies it out of the kernel's buffer
- // cache. This is significantly more efficient than doing write() from
- // a userspace memory buffer, since the latter makes the kernel copy
- // the same data from userspace many times.
- int data_fd;
-
- // How many bytes <data> contains. Can very well be larger than BACKLOG_SIZE,
- // since the buffer wraps.
- size_t data_size;
-
- // Clients that are in SENDING_DATA, but that we don't listen on,
- // because we currently don't have any data for them.
- // See put_client_to_sleep() and wake_up_all_clients().
- std::vector<Client *> sleeping_clients;
-
- // Clients that we recently got data for (when they were in
- // <sleeping_clients>).
- std::vector<Client *> to_process;
-
- // What pool to fetch marks from, or NULL.
- MarkPool *mark_pool;
-
- // Put client to sleep, since there is no more data for it; we will on
- // longer listen on POLLOUT until we get more data. Also, it will be put
- // in the list of clients to wake up when we do.
- void put_client_to_sleep(Client *client);
-
- // We have more data, so mark all clients that are sleeping as ready to go.
- void wake_up_all_clients();
-
-private:
- Stream(const Stream& other);
+ std::string url;
+ std::string referer;
+ std::string user_agent;
+ timespec expires;
};
class Server : public Thread {
// Get the list of all currently connected clients.
std::vector<ClientStats> get_client_stats() const;
+ // See hls_zombies, below.
+ std::vector<HLSZombie> get_hls_zombies();
+
// Set header (both HTTP header and any stream headers) for the given stream.
- void set_header(const std::string &stream_id, const std::string &header);
+ void set_header(int stream_index,
+ const std::string &http_header,
+ const std::string &stream_header);
+
+ // Sets the given stream as unavailable (will always return 503 to new clients).
+ void set_unavailable(int stream_index);
- // Set that the given stream should use the given mark pool from now on.
+ // Set that the given stream should use the given max pacing rate from now on.
// NOTE: This should be set before any clients are connected!
- void set_mark_pool(const std::string &stream_id, MarkPool *mark_pool);
+ void set_pacing_rate(int stream_index, uint32_t pacing_rate);
// These will be deferred until the next time an iteration in do_work() happens,
// and the order between them are undefined.
// XXX: header should ideally be ordered with respect to data.
- void add_client_deferred(int sock);
- void add_data_deferred(const std::string &stream_id, const char *data, size_t bytes);
+ void add_client_deferred(int sock, Acceptor *acceptor);
+ void add_data_deferred(int stream_index, const char *data, size_t bytes, uint16_t metacube_flags, const RationalPTS &pts);
// These should not be called while running, since that would violate
// threading assumptions (ie., that epoll is only called from one thread
// at the same time).
- CubemapStateProto serialize();
- void add_client_from_serialized(const ClientProto &client);
- void add_stream(const std::string &stream_id);
- void add_stream_from_serialized(const StreamProto &stream);
+ CubemapStateProto serialize(std::unordered_map<const std::string *, size_t> *short_response_pool);
+ void add_client_from_serialized(const ClientProto &client, const std::vector<std::shared_ptr<const std::string>> &short_responses);
+ int add_stream(const std::string &url,
+ const std::string &hls_url,
+ size_t bytes_received,
+ size_t prebuffering_bytes,
+ Stream::Encoding encoding,
+ Stream::Encoding src_encoding,
+ unsigned hls_frag_duration,
+ size_t hls_backlog_margin,
+ const std::string &allow_origin);
+ int add_stream_from_serialized(const StreamProto &stream, int data_fd);
+ void add_hls_zombie_from_serialized(const HLSZombieProto &hls_zombie);
+ int lookup_stream_by_url(const std::string &url) const;
+ void set_backlog_size(int stream_index, size_t new_size);
+ void set_prebuffering_bytes(int stream_index, size_t new_amount);
+ void set_encoding(int stream_index, Stream::Encoding encoding);
+ void set_src_encoding(int stream_index, Stream::Encoding encoding);
+ void set_hls_frag_duration(int stream_index, unsigned hls_frag_duration);
+ void set_hls_backlog_margin(int stream_index, size_t hls_backlog_margin);
+ void set_allow_origin(int stream_index, const std::string &allow_origin);
+ void register_hls_url(int stream_index, const std::string &hls_url);
+ void add_gen204(const std::string &url, const std::string &allow_origin);
+ void create_tls_context_for_acceptor(const Acceptor *acceptor);
private:
- // Mutex protecting queued_data only. Note that if you want to hold both this
- // and <mutex> below, you will need to take <mutex> before this one.
- mutable pthread_mutex_t queued_data_mutex;
+ // Mutex protecting queued_add_clients.
+ // Note that if you want to hold both this and <mu> below,
+ // you will need to take <mu> before this one.
+ mutable std::mutex queued_clients_mutex;
// Deferred commands that should be run from the do_work() thread as soon as possible.
// We defer these for two reasons:
//
// - We only want to fiddle with epoll from one thread at any given time,
// and doing add_client() from the acceptor thread would violate that.
- // - We don't want the input thread(s) hanging on <mutex> when doing
- // add_data(), since they want to do add_data() rather often, and <mutex>
+ // - We don't want the input thread(s) hanging on <mu> when doing
+ // add_data(), since they want to do add_data() rather often, and <mu>
// can be taken a lot of the time.
//
- // Protected by <queued_data_mutex>.
- std::vector<int> queued_add_clients;
- std::map<std::string, std::string> queued_data;
+ // Protected by <queued_clients_mutex>.
+ std::vector<std::pair<int, Acceptor *>> queued_add_clients;
// All variables below this line are protected by the mutex.
- mutable pthread_mutex_t mutex;
+ mutable std::mutex mu;
+
+ // All streams.
+ std::vector<std::unique_ptr<Stream>> streams;
- // Map from stream ID to stream.
- std::map<std::string, Stream *> streams;
+ // Map from URL to index into <streams>.
+ std::unordered_map<std::string, int> stream_url_map, stream_hls_url_map;
+
+ // Map from URL to CORS Allow-Origin header (or empty string).
+ std::unordered_map<std::string, std::string> ping_url_map;
// Map from file descriptor to client.
- std::map<int, Client> clients;
+ std::unordered_map<int, Client> clients;
+
+ // A list of all clients, ordered by the time they connected (first element),
+ // and their file descriptor (second element). It is ordered by connection time
+ // (and thus also by read timeout time) so that we can read clients from the
+ // start and stop processing once we get to one that isn't ready to be
+ // timed out yet (which means we only have to look at each client exactly once,
+ // save for the first element of the queue, which is always checked).
+ //
+ // Note that when we delete a client, we don't update this queue.
+ // This means that when reading it, we need to check if the client it
+ // describes is still exists (ie., that the fd still exists, and that
+ // the timespec matches).
+ std::queue<std::pair<timespec, int>> clients_ordered_by_connect_time;
+
+ // HLS is harder to keep viewer statistics for than regular streams,
+ // since there's no 1:1 mapping between ongoing HTTP connections and
+ // actual viewers. After a HLS fragment has been successfully sent,
+ // we keep a note of that in this structure, so that we can add some
+ // fake entries in the .stats file for clients that we believe are still
+ // watching, but are not downloading anything right now. We clean this
+ // out whenever we write statistics centrally.
+ //
+ // The structure is keyed by X-Playback-Session-Id if it exists
+ // (typically iOS clients) or IP address otherwise; we can't use the socket,
+ // since clients can (and do) keep open multiple HTTP connections for
+ // the same video playack session, and may also close the socket
+ // between downloading fragments. This means multiple clients between
+ // the same NAT may be undercounted, but that's how it is.
+ std::unordered_map<std::string, HLSZombie> hls_zombies;
// Used for epoll implementation (obviously).
int epoll_fd;
epoll_event events[EPOLL_MAX_EVENTS];
+ // For each TLS-enabled acceptor, our private server context for its key pair.
+ std::unordered_map<const Acceptor *, TLSContext *> tls_server_contexts;
+
// The actual worker thread.
virtual void do_work();
// but it's cheaper than taking it in and out all the time.
void process_client(Client *client);
+ // If the TLS library wants to write anything to this client,
+ // output it. Returns true if the processing should go to sleep
+ // (an error, or lack of outgoing buffer space).
+ bool send_pending_tls_data(Client *client);
+
+ // Reads regular data fro ma socket. Returns -1 if the processing
+ // should go to sleep (an error, or no data available yet), otherwise
+ // the number of bytes read.
+ int read_plain_data(Client *client, char *buf, size_t max_size);
+
+ // Reads (decrypted) data from a TLS socket. Returns -1 if the processing
+ // should go to sleep (an error, or no data available yet), otherwise
+ // the number of bytes read. The buffer will be used as scratch space
+ // for TLS data, so it can be overwritten by more bytes than what is returned.
+ int read_tls_data(Client *client, char *buf, size_t max_size);
+
// Close a given client socket, and clean up after it.
void close_client(Client *client);
- // Parse the HTTP request. Returns a HTTP status code (200/400/404).
+ // Listen for a different set of epoll events.
+ void change_epoll_events(Client *client, uint32_t events);
+
+ // If we're supposed to listen for more requests (persistent HTTP connections),
+ // puts the client back into READING_REQUEST, changes its epoll flags and returns
+ // true.
+ bool more_requests(Client *client);
+
+ // Parse the HTTP request. Returns a HTTP status code (200/204/400/404).
int parse_request(Client *client);
- // Construct the HTTP header, and set the client into
+ // Construct the HTTP header for a regular stream, and set the client into
// the SENDING_HEADER state.
- void construct_header(Client *client);
+ void construct_stream_header(Client *client);
+
+ // Construct a HLS playlist (or get it from the cache), and set the client into
+ // the SENDING_HEADER state.
+ void construct_hls_playlist(Client *client);
// Construct a generic error with the given line, and set the client into
- // the SENDING_ERROR state.
+ // the SENDING_SHORT_RESPONSE state.
void construct_error(Client *client, int error_code);
- // TODO: This function should probably die.
- Stream *find_stream(const std::string &stream_id);
+ // Construct a 204, and set the client into the SENDING_SHORT_RESPONSE state.
+ void construct_204(Client *client);
void process_queued_data();
+ void skip_lost_data(Client *client);
+
+ void add_client(int sock, Acceptor *acceptor);
- void add_client(int sock);
- void add_data(const std::string &stream_id, const char *data, ssize_t bytes);
+ // Mark that a client just went into READING_REQUEST state, so we should
+ // note the current time of day and then put it into <clients_ordered_by_connect_time>.
+ void start_client_timeout_timer(Client *client);
};
#endif // !defined(_SERVER_H)
projects / cubemap / blobdiff