22 #define EPOLL_MAX_EVENTS 8192
23 #define EPOLL_TIMEOUT_MS 20
24 #define MAX_CLIENT_REQUEST 16384
25 #define REQUEST_READ_TIMEOUT_SEC 60
27 class CubemapStateProto;
30 class Server : public Thread {
35 // Get the list of all currently connected clients.
36 std::vector<ClientStats> get_client_stats() const;
38 // Set header (both HTTP header and any stream headers) for the given stream.
39 void set_header(int stream_index,
40 const std::string &http_header,
41 const std::string &stream_header);
43 // Set that the given stream should use the given max pacing rate from now on.
44 // NOTE: This should be set before any clients are connected!
45 void set_pacing_rate(int stream_index, uint32_t pacing_rate);
47 // These will be deferred until the next time an iteration in do_work() happens,
48 // and the order between them are undefined.
49 // XXX: header should ideally be ordered with respect to data.
50 void add_client_deferred(int sock);
51 void add_data_deferred(int stream_index, const char *data, size_t bytes, StreamStartSuitability suitable_for_stream_start);
53 // These should not be called while running, since that would violate
54 // threading assumptions (ie., that epoll is only called from one thread
56 CubemapStateProto serialize();
57 void add_client_from_serialized(const ClientProto &client);
58 int add_stream(const std::string &url, size_t bytes_received, size_t prebuffering_bytes, Stream::Encoding encoding);
59 int add_stream_from_serialized(const StreamProto &stream, int data_fd);
60 int lookup_stream_by_url(const std::string &url) const;
61 void set_backlog_size(int stream_index, size_t new_size);
62 void set_encoding(int stream_index, Stream::Encoding encoding);
65 // Mutex protecting queued_add_clients.
66 // Note that if you want to hold both this and <mutex> below,
67 // you will need to take <mutex> before this one.
68 mutable pthread_mutex_t queued_clients_mutex;
70 // Deferred commands that should be run from the do_work() thread as soon as possible.
71 // We defer these for two reasons:
73 // - We only want to fiddle with epoll from one thread at any given time,
74 // and doing add_client() from the acceptor thread would violate that.
75 // - We don't want the input thread(s) hanging on <mutex> when doing
76 // add_data(), since they want to do add_data() rather often, and <mutex>
77 // can be taken a lot of the time.
79 // Protected by <queued_clients_mutex>.
80 std::vector<int> queued_add_clients;
82 // All variables below this line are protected by the mutex.
83 mutable pthread_mutex_t mutex;
86 std::vector<Stream *> streams;
88 // Map from URL to index into <streams>.
89 std::map<std::string, int> url_map;
91 // Map from file descriptor to client.
92 std::map<int, Client> clients;
94 // A list of all clients, ordered by the time they connected (first element),
95 // and their file descriptor (second element). It is ordered by connection time
96 // (and thus also by read timeout time) so that we can read clients from the
97 // start and stop processing once we get to one that isn't ready to be
98 // timed out yet (which makes each processing run amortized O(1)).
100 // Note that when we delete a client, we don't update this queue.
101 // This means that when reading it, we need to check if the client it
102 // describes is still exists (ie., that the fd still exists, and that
103 // the timespec matches).
104 std::queue<std::pair<timespec, int> > clients_ordered_by_connect_time;
106 // Used for epoll implementation (obviously).
108 epoll_event events[EPOLL_MAX_EVENTS];
110 // The actual worker thread.
111 virtual void do_work();
113 // Process a client; read and write data as far as we can.
114 // After this call, one of these four is true:
116 // 1. The socket is closed, and the client deleted.
117 // 2. We are still waiting for more data from the client.
118 // 3. We've sent all the data we have to the client,
119 // and put it in <sleeping_clients>.
120 // 4. The socket buffer is full (which means we still have
121 // data outstanding).
123 // For #2, we listen for EPOLLIN events. For #3 and #4, we listen
124 // for EPOLLOUT in edge-triggered mode; it will never fire for #3,
125 // but it's cheaper than taking it in and out all the time.
126 void process_client(Client *client);
128 // Close a given client socket, and clean up after it.
129 void close_client(Client *client);
131 // Parse the HTTP request. Returns a HTTP status code (200/400/404).
132 int parse_request(Client *client);
134 // Construct the HTTP header, and set the client into
135 // the SENDING_HEADER state.
136 void construct_header(Client *client);
138 // Construct a generic error with the given line, and set the client into
139 // the SENDING_ERROR state.
140 void construct_error(Client *client, int error_code);
142 void process_queued_data();
143 void skip_lost_data(Client *client);
145 void add_client(int sock);
148 #endif // !defined(_SERVER_H)