#ifndef _SERVER_H
#define _SERVER_H 1
-#include <stdint.h>
#include <pthread.h>
-#include <string>
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/epoll.h>
+#include <sys/types.h>
+#include <time.h>
#include <map>
+#include <queue>
+#include <string>
+#include <vector>
-#define BACKLOG_SIZE 1048576
-
-struct Client {
- enum State { READING_REQUEST, SENDING_HEADER, SENDING_DATA };
- State state;
-
- // The HTTP request, as sent by the client. If we are in READING_REQUEST,
- // this might not be finished.
- std::string client_request;
-
-#if 0
- // What stream we're connecting to; parsed from client_request.
- // Not relevant for READING_REQUEST.
- string stream_id;
-#endif
-
- // Number of bytes we've sent of the header. Only relevant for SENDING_HEADER.
- size_t header_bytes_sent;
+#include "client.h"
+#include "stream.h"
+#include "thread.h"
- // Number of bytes we've sent of data. Only relevant for SENDING_DATA.
- size_t bytes_sent;
-};
+class ClientProto;
+struct Stream;
-struct Stream {
- // The HTTP response header, plus the video stream header (if any).
- std::string header;
+#define EPOLL_MAX_EVENTS 8192
+#define EPOLL_TIMEOUT_MS 20
+#define MAX_CLIENT_REQUEST 16384
+#define REQUEST_READ_TIMEOUT_SEC 60
- // The stream data itself, stored in a circular buffer.
- char data[BACKLOG_SIZE];
+class CubemapStateProto;
+class StreamProto;
- // How many bytes <data> contains. Can very well be larger than BACKLOG_SIZE,
- // since the buffer wraps.
- size_t data_size;
-};
-
-class Server {
+class Server : public Thread {
public:
Server();
-
- // Start a new thread that handles clients.
- void run();
- void add_client(int sock);
- void add_stream(const std::string &stream_id);
- 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);
+ ~Server();
+
+ // Get the list of all currently connected clients.
+ std::vector<ClientStats> get_client_stats() const;
+
+ // Set header (both HTTP header and any stream headers) for the given stream.
+ void set_header(int stream_index,
+ const std::string &http_header,
+ const std::string &stream_header);
+
+ // 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_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(int stream_index, const char *data, size_t bytes, StreamStartSuitability suitable_for_stream_start);
+
+ // 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);
+ int add_stream(const std::string &url, size_t bytes_received, size_t prebuffering_bytes, Stream::Encoding encoding);
+ int add_stream_from_serialized(const StreamProto &stream, int data_fd);
+ 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);
private:
- pthread_mutex_t mutex;
-
- // Map from stream ID to stream.
- std::map<std::string, Stream> streams;
+ // Mutex protecting queued_add_clients.
+ // 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_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>
+ // can be taken a lot of the time.
+ //
+ // Protected by <queued_clients_mutex>.
+ std::vector<int> queued_add_clients;
+
+ // All variables below this line are protected by the mutex.
+ mutable pthread_mutex_t mutex;
+
+ // All streams.
+ std::vector<Stream *> streams;
+
+ // Map from URL to index into <streams>.
+ std::map<std::string, int> url_map;
// Map from file descriptor to client.
std::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;
+
+ // Used for epoll implementation (obviously).
int epoll_fd;
-
- // Recover the this pointer, and call do_work().
- static void *do_work_thunk(void *arg);
+ epoll_event events[EPOLL_MAX_EVENTS];
// The actual worker thread.
- void do_work();
+ virtual 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 <sleeping_clients>.
+ // 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. 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);
+
+ // 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);
+
+ void process_queued_data();
+ void skip_lost_data(Client *client);
+
+ void add_client(int sock);
};
#endif // !defined(_SERVER_H)