13 #include <unordered_map>
26 #define EPOLL_MAX_EVENTS 8192
27 #define EPOLL_TIMEOUT_MS 20
28 #define MAX_CLIENT_REQUEST 16384
29 #define REQUEST_READ_TIMEOUT_SEC 60
31 class CubemapStateProto;
34 class Server : public Thread {
39 // Get the list of all currently connected clients.
40 std::vector<ClientStats> get_client_stats() const;
42 // Set header (both HTTP header and any stream headers) for the given stream.
43 void set_header(int stream_index,
44 const std::string &http_header,
45 const std::string &stream_header);
47 // Set that the given stream should use the given max pacing rate from now on.
48 // NOTE: This should be set before any clients are connected!
49 void set_pacing_rate(int stream_index, uint32_t pacing_rate);
51 // These will be deferred until the next time an iteration in do_work() happens,
52 // and the order between them are undefined.
53 // XXX: header should ideally be ordered with respect to data.
54 void add_client_deferred(int sock, Acceptor *acceptor);
55 void add_data_deferred(int stream_index, const char *data, size_t bytes, uint16_t metacube_flags, const RationalPTS &pts);
57 // These should not be called while running, since that would violate
58 // threading assumptions (ie., that epoll is only called from one thread
60 CubemapStateProto serialize(std::unordered_map<const std::string *, size_t> *short_response_pool);
61 void add_client_from_serialized(const ClientProto &client, const std::vector<std::shared_ptr<const std::string>> &short_responses);
62 int add_stream(const std::string &url,
63 const std::string &hls_url,
64 size_t bytes_received,
65 size_t prebuffering_bytes,
66 Stream::Encoding encoding,
67 Stream::Encoding src_encoding,
68 unsigned hls_frag_duration,
69 size_t hls_backlog_margin,
70 const std::string &allow_origin);
71 int add_stream_from_serialized(const StreamProto &stream, int data_fd);
72 int lookup_stream_by_url(const std::string &url) const;
73 void set_backlog_size(int stream_index, size_t new_size);
74 void set_prebuffering_bytes(int stream_index, size_t new_amount);
75 void set_encoding(int stream_index, Stream::Encoding encoding);
76 void set_src_encoding(int stream_index, Stream::Encoding encoding);
77 void set_hls_frag_duration(int stream_index, unsigned hls_frag_duration);
78 void set_hls_backlog_margin(int stream_index, size_t hls_backlog_margin);
79 void set_allow_origin(int stream_index, const std::string &allow_origin);
80 void register_hls_url(int stream_index, const std::string &hls_url);
81 void add_gen204(const std::string &url, const std::string &allow_origin);
82 void create_tls_context_for_acceptor(const Acceptor *acceptor);
85 // Mutex protecting queued_add_clients.
86 // Note that if you want to hold both this and <mu> below,
87 // you will need to take <mu> before this one.
88 mutable std::mutex queued_clients_mutex;
90 // Deferred commands that should be run from the do_work() thread as soon as possible.
91 // We defer these for two reasons:
93 // - We only want to fiddle with epoll from one thread at any given time,
94 // and doing add_client() from the acceptor thread would violate that.
95 // - We don't want the input thread(s) hanging on <mu> when doing
96 // add_data(), since they want to do add_data() rather often, and <mu>
97 // can be taken a lot of the time.
99 // Protected by <queued_clients_mutex>.
100 std::vector<std::pair<int, Acceptor *>> queued_add_clients;
102 // All variables below this line are protected by the mutex.
103 mutable std::mutex mu;
106 std::vector<std::unique_ptr<Stream>> streams;
108 // Map from URL to index into <streams>.
109 std::unordered_map<std::string, int> stream_url_map, stream_hls_url_map;
111 // Map from URL to CORS Allow-Origin header (or empty string).
112 std::unordered_map<std::string, std::string> ping_url_map;
114 // Map from file descriptor to client.
115 std::unordered_map<int, Client> clients;
117 // A list of all clients, ordered by the time they connected (first element),
118 // and their file descriptor (second element). It is ordered by connection time
119 // (and thus also by read timeout time) so that we can read clients from the
120 // start and stop processing once we get to one that isn't ready to be
121 // timed out yet (which means we only have to look at each client exactly once,
122 // save for the first element of the queue, which is always checked).
124 // Note that when we delete a client, we don't update this queue.
125 // This means that when reading it, we need to check if the client it
126 // describes is still exists (ie., that the fd still exists, and that
127 // the timespec matches).
128 std::queue<std::pair<timespec, int>> clients_ordered_by_connect_time;
130 // Used for epoll implementation (obviously).
132 epoll_event events[EPOLL_MAX_EVENTS];
134 // For each TLS-enabled acceptor, our private server context for its key pair.
135 std::unordered_map<const Acceptor *, TLSContext *> tls_server_contexts;
137 // The actual worker thread.
138 virtual void do_work();
140 // Process a client; read and write data as far as we can.
141 // After this call, one of these four is true:
143 // 1. The socket is closed, and the client deleted.
144 // 2. We are still waiting for more data from the client.
145 // 3. We've sent all the data we have to the client,
146 // and put it in <sleeping_clients>.
147 // 4. The socket buffer is full (which means we still have
148 // data outstanding).
150 // For #2, we listen for EPOLLIN events. For #3 and #4, we listen
151 // for EPOLLOUT in edge-triggered mode; it will never fire for #3,
152 // but it's cheaper than taking it in and out all the time.
153 void process_client(Client *client);
155 // If the TLS library wants to write anything to this client,
156 // output it. Returns true if the processing should go to sleep
157 // (an error, or lack of outgoing buffer space).
158 bool send_pending_tls_data(Client *client);
160 // Reads regular data fro ma socket. Returns -1 if the processing
161 // should go to sleep (an error, or no data available yet), otherwise
162 // the number of bytes read.
163 int read_nontls_data(Client *client, char *buf, size_t max_size);
165 // Reads (decrypted) data from a TLS socket. Returns -1 if the processing
166 // should go to sleep (an error, or no data available yet), otherwise
167 // the number of bytes read. The buffer will be used as scratch space
168 // for TLS data, so it can be overwritten by more bytes than what is returned.
169 int read_tls_data(Client *client, char *buf, size_t max_size);
171 // Close a given client socket, and clean up after it.
172 void close_client(Client *client);
174 // Listen for a different set of epoll events.
175 void change_epoll_events(Client *client, uint32_t events);
177 // If we're supposed to listen for more requests (persistent HTTP connections),
178 // puts the client back into READING_REQUEST, changes its epoll flags and returns
180 bool more_requests(Client *client);
182 // Parse the HTTP request. Returns a HTTP status code (200/204/400/404).
183 int parse_request(Client *client);
185 // Construct the HTTP header for a regular stream, and set the client into
186 // the SENDING_HEADER state.
187 void construct_stream_header(Client *client);
189 // Construct a HLS playlist (or get it from the cache), and set the client into
190 // the SENDING_HEADER state.
191 void construct_hls_playlist(Client *client);
193 // Construct a generic error with the given line, and set the client into
194 // the SENDING_SHORT_RESPONSE state.
195 void construct_error(Client *client, int error_code);
197 // Construct a 204, and set the client into the SENDING_SHORT_RESPONSE state.
198 void construct_204(Client *client);
200 void process_queued_data();
201 void skip_lost_data(Client *client);
203 void add_client(int sock, Acceptor *acceptor);
206 #endif // !defined(_SERVER_H)