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

   1 #include <arpa/inet.h>
   2 #include <assert.h>
   3 #include <endian.h>
   4 #include <microhttpd.h>
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <string.h>
   8
   9 #include <vector>
  10
  11 #include "httpd.h"
  12
  13 #include "defs.h"
  14 #include "flags.h"
  15 #include "metacube2.h"
  16 #include "timebase.h"
  17
  18 struct MHD_Connection;
  19 struct MHD_Response;
  20
  21 using namespace std;
  22
  23 HTTPD::HTTPD()
  24 {
  25 }
  26
  27 HTTPD::~HTTPD()
  28 {
  29         if (mhd) {
  30                 MHD_quiesce_daemon(mhd);
  31                 for (Stream *stream : streams) {
  32                         stream->stop();
  33                 }
  34                 MHD_stop_daemon(mhd);
  35         }
  36 }
  37
  38 void HTTPD::start(int port)
  39 {
  40         mhd = MHD_start_daemon(MHD_USE_THREAD_PER_CONNECTION | MHD_USE_POLL_INTERNALLY | MHD_USE_DUAL_STACK,
  41                                port,
  42                                nullptr, nullptr,
  43                                &answer_to_connection_thunk, this,
  44                                MHD_OPTION_NOTIFY_COMPLETED, nullptr, this,
  45                                MHD_OPTION_END);
  46         if (mhd == nullptr) {
  47                 fprintf(stderr, "Warning: Could not open HTTP server. (Port already in use?)\n");
  48         }
  49 }
  50
  51 void HTTPD::add_data(const char *buf, size_t size, bool keyframe)
  52 {
  53         unique_lock<mutex> lock(streams_mutex);
  54         for (Stream *stream : streams) {
  55                 stream->add_data(buf, size, keyframe ? Stream::DATA_TYPE_KEYFRAME : Stream::DATA_TYPE_OTHER);
  56         }
  57 }
  58
  59 int HTTPD::answer_to_connection_thunk(void *cls, MHD_Connection *connection,
  60                                       const char *url, const char *method,
  61                                       const char *version, const char *upload_data,
  62                                       size_t *upload_data_size, void **con_cls)
  63 {
  64         HTTPD *httpd = (HTTPD *)cls;
  65         return httpd->answer_to_connection(connection, url, method, version, upload_data, upload_data_size, con_cls);
  66 }
  67
  68 int HTTPD::answer_to_connection(MHD_Connection *connection,
  69                                 const char *url, const char *method,
  70                                 const char *version, const char *upload_data,
  71                                 size_t *upload_data_size, void **con_cls)
  72 {
  73         // See if the URL ends in “.metacube”.
  74         HTTPD::Stream::Framing framing;
  75         if (strstr(url, ".metacube") == url + strlen(url) - strlen(".metacube")) {
  76                 framing = HTTPD::Stream::FRAMING_METACUBE;
  77         } else {
  78                 framing = HTTPD::Stream::FRAMING_RAW;
  79         }
  80
  81         HTTPD::Stream *stream = new HTTPD::Stream(this, framing);
  82         stream->add_data(header.data(), header.size(), Stream::DATA_TYPE_HEADER);
  83         {
  84                 unique_lock<mutex> lock(streams_mutex);
  85                 streams.insert(stream);
  86         }
  87         *con_cls = stream;
  88
  89         // Does not strictly have to be equal to MUX_BUFFER_SIZE.
  90         MHD_Response *response = MHD_create_response_from_callback(
  91                 (size_t)-1, MUX_BUFFER_SIZE, &HTTPD::Stream::reader_callback_thunk, stream, &HTTPD::free_stream);
  92
  93         // TODO: Content-type?
  94         if (framing == HTTPD::Stream::FRAMING_METACUBE) {
  95                 MHD_add_response_header(response, "Content-encoding", "metacube");
  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
 100         return ret;
 101 }
 102
 103 void HTTPD::free_stream(void *cls)
 104 {
 105         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 106         HTTPD *httpd = stream->get_parent();
 107         {
 108                 unique_lock<mutex> lock(httpd->streams_mutex);
 109                 delete stream;
 110                 httpd->streams.erase(stream);
 111         }
 112 }
 113
 114 ssize_t HTTPD::Stream::reader_callback_thunk(void *cls, uint64_t pos, char *buf, size_t max)
 115 {
 116         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 117         return stream->reader_callback(pos, buf, max);
 118 }
 119
 120 ssize_t HTTPD::Stream::reader_callback(uint64_t pos, char *buf, size_t max)
 121 {
 122         unique_lock<mutex> lock(buffer_mutex);
 123         has_buffered_data.wait(lock, [this]{ return should_quit || !buffered_data.empty(); });
 124         if (should_quit) {
 125                 return 0;
 126         }
 127
 128         ssize_t ret = 0;
 129         while (max > 0 && !buffered_data.empty()) {
 130                 const string &s = buffered_data.front();
 131                 assert(s.size() > used_of_buffered_data);
 132                 size_t len = s.size() - used_of_buffered_data;
 133                 if (max >= len) {
 134                         // Consume the entire (rest of the) string.
 135                         memcpy(buf, s.data() + used_of_buffered_data, len);
 136                         buf += len;
 137                         ret += len;
 138                         max -= len;
 139                         buffered_data.pop_front();
 140                         used_of_buffered_data = 0;
 141                 } else {
 142                         // We don't need the entire string; just use the first part of it.
 143                         memcpy(buf, s.data() + used_of_buffered_data, max);
 144                         buf += max;
 145                         used_of_buffered_data += max;
 146                         ret += max;
 147                         max = 0;
 148                 }
 149         }
 150
 151         return ret;
 152 }
 153
 154 void HTTPD::Stream::add_data(const char *buf, size_t buf_size, HTTPD::Stream::DataType data_type)
 155 {
 156         if (buf_size == 0) {
 157                 return;
 158         }
 159         if (data_type == DATA_TYPE_KEYFRAME) {
 160                 seen_keyframe = true;
 161         } else if (data_type == DATA_TYPE_OTHER && !seen_keyframe) {
 162                 // Start sending only once we see a keyframe.
 163                 return;
 164         }
 165
 166         unique_lock<mutex> lock(buffer_mutex);
 167
 168         if (framing == FRAMING_METACUBE) {
 169                 metacube2_block_header hdr;
 170                 memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
 171                 hdr.size = htonl(buf_size);
 172                 int flags = 0;
 173                 if (data_type == DATA_TYPE_HEADER) {
 174                         flags |= METACUBE_FLAGS_HEADER;
 175                 } else if (data_type == DATA_TYPE_OTHER) {
 176                         flags |= METACUBE_FLAGS_NOT_SUITABLE_FOR_STREAM_START;
 177                 }
 178                 hdr.flags = htons(flags);
 179                 hdr.csum = htons(metacube2_compute_crc(&hdr));
 180                 buffered_data.emplace_back((char *)&hdr, sizeof(hdr));
 181         }
 182         buffered_data.emplace_back(buf, buf_size);
 183
 184         // Send a Metacube2 timestamp every keyframe.
 185         if (framing == FRAMING_METACUBE && data_type == DATA_TYPE_KEYFRAME) {
 186                 timespec now;
 187                 clock_gettime(CLOCK_REALTIME, &now);
 188
 189                 metacube2_timestamp_packet packet;
 190                 packet.type = htobe64(METACUBE_METADATA_TYPE_ENCODER_TIMESTAMP);
 191                 packet.tv_sec = htobe64(now.tv_sec);
 192                 packet.tv_nsec = htobe64(now.tv_nsec);
 193
 194                 metacube2_block_header hdr;
 195                 memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
 196                 hdr.size = htonl(sizeof(packet));
 197                 hdr.flags = htons(METACUBE_FLAGS_METADATA);
 198                 hdr.csum = htons(metacube2_compute_crc(&hdr));
 199                 buffered_data.emplace_back((char *)&hdr, sizeof(hdr));
 200                 buffered_data.emplace_back((char *)&packet, sizeof(packet));
 201         }
 202
 203         has_buffered_data.notify_all();
 204 }
 205
 206 void HTTPD::Stream::stop()
 207 {
 208         unique_lock<mutex> lock(buffer_mutex);
 209         should_quit = true;
 210         has_buffered_data.notify_all();
 211 }