git.sesse.net Git - nageru/blob - shared/httpd.cpp

   1 #include "shared/httpd.h"
   2
   3 #include <assert.h>
   4 #include <byteswap.h>
   5 #include <endian.h>
   6 #include <memory>
   7 #include <microhttpd.h>
   8 #include <netinet/in.h>
   9 #include <stdio.h>
  10 #include <string.h>
  11 #include <sys/time.h>
  12 #include <time.h>
  13 extern "C" {
  14 #include <libavutil/avutil.h>
  15 }
  16
  17 #include "shared/shared_defs.h"
  18 #include "shared/metacube2.h"
  19 #include "shared/metrics.h"
  20
  21 struct MHD_Connection;
  22 struct MHD_Response;
  23
  24 using namespace std;
  25
  26 HTTPD::HTTPD()
  27 {
  28         global_metrics.add("num_connected_clients", &metric_num_connected_clients, Metrics::TYPE_GAUGE);
  29         global_metrics.add("num_connected_multicam_clients", &metric_num_connected_multicam_clients, Metrics::TYPE_GAUGE);
  30 }
  31
  32 HTTPD::~HTTPD()
  33 {
  34         stop();
  35 }
  36
  37 void HTTPD::start(int port)
  38 {
  39         mhd = MHD_start_daemon(MHD_USE_THREAD_PER_CONNECTION | MHD_USE_POLL_INTERNALLY | MHD_USE_DUAL_STACK,
  40                                port,
  41                                nullptr, nullptr,
  42                                &answer_to_connection_thunk, this,
  43                                MHD_OPTION_NOTIFY_COMPLETED, nullptr, this,
  44                                MHD_OPTION_END);
  45         if (mhd == nullptr) {
  46                 fprintf(stderr, "Warning: Could not open HTTP server. (Port already in use?)\n");
  47         }
  48 }
  49
  50 void HTTPD::stop()
  51 {
  52         if (mhd) {
  53                 MHD_quiesce_daemon(mhd);
  54                 for (Stream *stream : streams) {
  55                         stream->stop();
  56                 }
  57                 MHD_stop_daemon(mhd);
  58                 mhd = nullptr;
  59         }
  60 }
  61
  62 void HTTPD::add_data(StreamType stream_type, const char *buf, size_t size, bool keyframe, int64_t time, AVRational timebase)
  63 {
  64         unique_lock<mutex> lock(streams_mutex);
  65         for (Stream *stream : streams) {
  66                 if (stream->get_stream_type() == stream_type) {
  67                         stream->add_data(buf, size, keyframe ? Stream::DATA_TYPE_KEYFRAME : Stream::DATA_TYPE_OTHER, time, timebase);
  68                 }
  69         }
  70 }
  71
  72 int HTTPD::answer_to_connection_thunk(void *cls, MHD_Connection *connection,
  73                                       const char *url, const char *method,
  74                                       const char *version, const char *upload_data,
  75                                       size_t *upload_data_size, void **con_cls)
  76 {
  77         HTTPD *httpd = (HTTPD *)cls;
  78         return httpd->answer_to_connection(connection, url, method, version, upload_data, upload_data_size, con_cls);
  79 }
  80
  81 int HTTPD::answer_to_connection(MHD_Connection *connection,
  82                                 const char *url, const char *method,
  83                                 const char *version, const char *upload_data,
  84                                 size_t *upload_data_size, void **con_cls)
  85 {
  86         // See if the URL ends in “.metacube”.
  87         HTTPD::Stream::Framing framing;
  88         if (strstr(url, ".metacube") == url + strlen(url) - strlen(".metacube")) {
  89                 framing = HTTPD::Stream::FRAMING_METACUBE;
  90         } else {
  91                 framing = HTTPD::Stream::FRAMING_RAW;
  92         }
  93         HTTPD::StreamType stream_type;
  94         if (strcmp(url, "/multicam.mp4") == 0) {
  95                 stream_type = HTTPD::StreamType::MULTICAM_STREAM;
  96         } else {
  97                 stream_type = HTTPD::StreamType::MAIN_STREAM;
  98         }
  99
 100         if (strcmp(url, "/metrics") == 0) {
 101                 string contents = global_metrics.serialize();
 102                 MHD_Response *response = MHD_create_response_from_buffer(
 103                         contents.size(), &contents[0], MHD_RESPMEM_MUST_COPY);
 104                 MHD_add_response_header(response, "Content-type", "text/plain");
 105                 int ret = MHD_queue_response(connection, MHD_HTTP_OK, response);
 106                 MHD_destroy_response(response);  // Only decreases the refcount; actual free is after the request is done.
 107                 return ret;
 108         }
 109         if (endpoints.count(url)) {
 110                 pair<string, string> contents_and_type = endpoints[url].callback();
 111                 MHD_Response *response = MHD_create_response_from_buffer(
 112                         contents_and_type.first.size(), &contents_and_type.first[0], MHD_RESPMEM_MUST_COPY);
 113                 MHD_add_response_header(response, "Content-type", contents_and_type.second.c_str());
 114                 if (endpoints[url].cors_policy == ALLOW_ALL_ORIGINS) {
 115                         MHD_add_response_header(response, "Access-Control-Allow-Origin", "*");
 116                 }
 117                 int ret = MHD_queue_response(connection, MHD_HTTP_OK, response);
 118                 MHD_destroy_response(response);  // Only decreases the refcount; actual free is after the request is done.
 119                 return ret;
 120         }
 121
 122         // Small hack; reject unknown /channels/foo.
 123         if (string(url).find("/channels/") == 0) {
 124                 string contents = "Not found.";
 125                 MHD_Response *response = MHD_create_response_from_buffer(
 126                         contents.size(), &contents[0], MHD_RESPMEM_MUST_COPY);
 127                 MHD_add_response_header(response, "Content-type", "text/plain");
 128                 int ret = MHD_queue_response(connection, MHD_HTTP_NOT_FOUND, response);
 129                 MHD_destroy_response(response);  // Only decreases the refcount; actual free is after the request is done.
 130                 return ret;
 131         }
 132
 133         HTTPD::Stream *stream = new HTTPD::Stream(this, framing, stream_type);
 134         stream->add_data(header[stream_type].data(), header[stream_type].size(), Stream::DATA_TYPE_HEADER, AV_NOPTS_VALUE, AVRational{ 1, 0 });
 135         {
 136                 unique_lock<mutex> lock(streams_mutex);
 137                 streams.insert(stream);
 138         }
 139         ++metric_num_connected_clients;
 140         if (stream_type == HTTPD::StreamType::MULTICAM_STREAM) {
 141                 ++metric_num_connected_multicam_clients;
 142         }
 143         *con_cls = stream;
 144
 145         // Does not strictly have to be equal to MUX_BUFFER_SIZE.
 146         MHD_Response *response = MHD_create_response_from_callback(
 147                 (size_t)-1, MUX_BUFFER_SIZE, &HTTPD::Stream::reader_callback_thunk, stream, &HTTPD::free_stream);
 148         // TODO: Content-type?
 149         if (framing == HTTPD::Stream::FRAMING_METACUBE) {
 150                 MHD_add_response_header(response, "Content-encoding", "metacube");
 151         }
 152
 153         int ret = MHD_queue_response(connection, MHD_HTTP_OK, response);
 154         MHD_destroy_response(response);  // Only decreases the refcount; actual free is after the request is done.
 155
 156         return ret;
 157 }
 158
 159 void HTTPD::free_stream(void *cls)
 160 {
 161         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 162         HTTPD *httpd = stream->get_parent();
 163         if (stream->get_stream_type() == HTTPD::StreamType::MULTICAM_STREAM) {
 164                 --httpd->metric_num_connected_multicam_clients;
 165         }
 166         {
 167                 unique_lock<mutex> lock(httpd->streams_mutex);
 168                 delete stream;
 169                 httpd->streams.erase(stream);
 170         }
 171         --httpd->metric_num_connected_clients;
 172 }
 173
 174 ssize_t HTTPD::Stream::reader_callback_thunk(void *cls, uint64_t pos, char *buf, size_t max)
 175 {
 176         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 177         return stream->reader_callback(pos, buf, max);
 178 }
 179
 180 ssize_t HTTPD::Stream::reader_callback(uint64_t pos, char *buf, size_t max)
 181 {
 182         unique_lock<mutex> lock(buffer_mutex);
 183         has_buffered_data.wait(lock, [this] { return should_quit || !buffered_data.empty(); });
 184         if (should_quit) {
 185                 return 0;
 186         }
 187
 188         ssize_t ret = 0;
 189         while (max > 0 && !buffered_data.empty()) {
 190                 const string &s = buffered_data.front();
 191                 assert(s.size() > used_of_buffered_data);
 192                 size_t len = s.size() - used_of_buffered_data;
 193                 if (max >= len) {
 194                         // Consume the entire (rest of the) string.
 195                         memcpy(buf, s.data() + used_of_buffered_data, len);
 196                         buf += len;
 197                         ret += len;
 198                         max -= len;
 199                         buffered_data.pop_front();
 200                         used_of_buffered_data = 0;
 201                 } else {
 202                         // We don't need the entire string; just use the first part of it.
 203                         memcpy(buf, s.data() + used_of_buffered_data, max);
 204                         buf += max;
 205                         used_of_buffered_data += max;
 206                         ret += max;
 207                         max = 0;
 208                 }
 209         }
 210
 211         return ret;
 212 }
 213
 214 void HTTPD::Stream::add_data(const char *buf, size_t buf_size, HTTPD::Stream::DataType data_type, int64_t time, AVRational timebase)
 215 {
 216         if (buf_size == 0) {
 217                 return;
 218         }
 219         if (data_type == DATA_TYPE_KEYFRAME) {
 220                 seen_keyframe = true;
 221         } else if (data_type == DATA_TYPE_OTHER && !seen_keyframe) {
 222                 // Start sending only once we see a keyframe.
 223                 return;
 224         }
 225
 226         unique_lock<mutex> lock(buffer_mutex);
 227
 228         if (framing == FRAMING_METACUBE) {
 229                 int flags = 0;
 230                 if (data_type == DATA_TYPE_HEADER) {
 231                         flags |= METACUBE_FLAGS_HEADER;
 232                 } else if (data_type == DATA_TYPE_OTHER) {
 233                         flags |= METACUBE_FLAGS_NOT_SUITABLE_FOR_STREAM_START;
 234                 }
 235
 236                 // If we're about to send a keyframe, send a pts metadata block
 237                 // to mark its time.
 238                 if ((flags & METACUBE_FLAGS_NOT_SUITABLE_FOR_STREAM_START) == 0 && time != AV_NOPTS_VALUE) {
 239                         metacube2_pts_packet packet;
 240                         packet.type = htobe64(METACUBE_METADATA_TYPE_NEXT_BLOCK_PTS);
 241                         packet.pts = htobe64(time);
 242                         packet.timebase_num = htobe64(timebase.num);
 243                         packet.timebase_den = htobe64(timebase.den);
 244
 245                         metacube2_block_header hdr;
 246                         memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
 247                         hdr.size = htonl(sizeof(packet));
 248                         hdr.flags = htons(METACUBE_FLAGS_METADATA);
 249                         hdr.csum = htons(metacube2_compute_crc(&hdr));
 250                         buffered_data.emplace_back((char *)&hdr, sizeof(hdr));
 251                         buffered_data.emplace_back((char *)&packet, sizeof(packet));
 252                 }
 253
 254                 metacube2_block_header hdr;
 255                 memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
 256                 hdr.size = htonl(buf_size);
 257                 hdr.flags = htons(flags);
 258                 hdr.csum = htons(metacube2_compute_crc(&hdr));
 259                 buffered_data.emplace_back((char *)&hdr, sizeof(hdr));
 260         }
 261         buffered_data.emplace_back(buf, buf_size);
 262
 263         // Send a Metacube2 timestamp every keyframe.
 264         if (framing == FRAMING_METACUBE && data_type == DATA_TYPE_KEYFRAME) {
 265                 timespec now;
 266                 clock_gettime(CLOCK_REALTIME, &now);
 267
 268                 metacube2_timestamp_packet packet;
 269                 packet.type = htobe64(METACUBE_METADATA_TYPE_ENCODER_TIMESTAMP);
 270                 packet.tv_sec = htobe64(now.tv_sec);
 271                 packet.tv_nsec = htobe64(now.tv_nsec);
 272
 273                 metacube2_block_header hdr;
 274                 memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
 275                 hdr.size = htonl(sizeof(packet));
 276                 hdr.flags = htons(METACUBE_FLAGS_METADATA);
 277                 hdr.csum = htons(metacube2_compute_crc(&hdr));
 278                 buffered_data.emplace_back((char *)&hdr, sizeof(hdr));
 279                 buffered_data.emplace_back((char *)&packet, sizeof(packet));
 280         }
 281
 282         has_buffered_data.notify_all();
 283 }
 284
 285 void HTTPD::Stream::stop()
 286 {
 287         unique_lock<mutex> lock(buffer_mutex);
 288         should_quit = true;
 289         has_buffered_data.notify_all();
 290 }