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

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