X-Git-Url: https://git.sesse.net/?p=cubemap;a=blobdiff_plain;f=server.h;h=ce9365d7a49cfb98d176d9a566358c2a5f98d937;hp=2cb078e3fc418bdd6b47665bba31635b3af6e4e2;hb=c2c9f6441f9ae8091a39aea0340417d5915e1ac9;hpb=b59fa7ce2d47f135ea027548cc89f937a5fa875b diff --git a/server.h b/server.h index 2cb078e..ce9365d 100644 --- a/server.h +++ b/server.h @@ -15,6 +15,7 @@ class ClientProto; class CubemapStateProto; +class Stream; class StreamProto; struct Client { @@ -22,13 +23,13 @@ struct Client { Client(int sock); // Serialization/deserialization. - Client(const ClientProto &serialized); + Client(const ClientProto &serialized, Stream *stream); ClientProto serialize() const; // The file descriptor associated with this socket. int sock; - enum State { READING_REQUEST, SENDING_HEADER, SENDING_DATA }; + 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, @@ -38,14 +39,16 @@ struct Client { // What stream we're connecting to; parsed from . // 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; blank otherwise. - std::string header; + // 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. - size_t header_bytes_sent; + // 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; @@ -70,6 +73,23 @@ struct Stream { // How many bytes 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 sleeping_clients; + + // Clients that we recently got data for (when they were in + // ). + std::vector to_process; + + // 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); @@ -85,21 +105,43 @@ public: // Stop the thread. void stop(); + + void set_header(const std::string &stream_id, const std::string &header); - CubemapStateProto serialize() const; + // 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(int sock); + // 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); - void set_header(const std::string &stream_id, const std::string &header); - void add_data(const std::string &stream_id, const char *data, size_t bytes); - private: pthread_t worker_thread; + // Mutex protecting queued_data only. Note that if you want to hold both this + // and below, you will need to take before this one. + pthread_mutex_t queued_data_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 when doing + // add_data(), since they want to do add_data() rather often, and + // can be taken a lot of the time. + // + // Protected by . + std::vector queued_add_clients; + std::map queued_data; + // All variables below this line are protected by the mutex. pthread_mutex_t mutex; @@ -116,39 +158,48 @@ private: int epoll_fd; epoll_event events[EPOLL_MAX_EVENTS]; - // 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 sleeping_clients; - // Recover the this pointer, and call do_work(). static void *do_work_thunk(void *arg); // The actual worker thread. void do_work(); + // Process a client; read and write data as far as we can. + // After this call, one of these four is true: + // + // 1. The socket is closed, and the client deleted. + // 2. We are still waiting for more data from the client. + // 3. We've sent all the data we have to the client, + // and put it in . + // 4. The socket buffer is full (which means we still have + // data outstanding). + // + // For #2, we listen for EPOLLIN events. For #3 and #4, we listen + // for EPOLLOUT in edge-triggered mode; it will never fire for #3, + // but it's cheaper than taking it in and out all the time. void process_client(Client *client); // Close a given client socket, and clean up after it. void close_client(Client *client); - // Parse the HTTP request. - void parse_request(Client *client); + // Parse the HTTP request. Returns a HTTP status code (200/400/404). + int parse_request(Client *client); // Construct the HTTP header, and set the client into // the SENDING_HEADER state. void construct_header(Client *client); - // 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(); + // Construct a generic error with the given line, and set the client into + // the SENDING_ERROR state. + void construct_error(Client *client, int error_code); // TODO: This function should probably die. Stream *find_stream(const std::string &stream_id); + + void process_queued_data(); + + void add_client(int sock); + void add_data(const std::string &stream_id, const char *data, size_t bytes); }; #endif // !defined(_SERVER_H)