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