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         MHD_quiesce_daemon(mhd);
  30         for (Stream *stream : streams) {
  31                 stream->stop();
  32         }
  33         MHD_stop_daemon(mhd);
  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 }
  45
  46 void HTTPD::add_data(const char *buf, size_t size, bool keyframe)
  47 {
  48         unique_lock<mutex> lock(streams_mutex);
  49         for (Stream *stream : streams) {
  50                 stream->add_data(buf, size, keyframe ? Stream::DATA_TYPE_KEYFRAME : Stream::DATA_TYPE_OTHER);
  51         }
  52 }
  53
  54 int HTTPD::answer_to_connection_thunk(void *cls, MHD_Connection *connection,
  55                                       const char *url, const char *method,
  56                                       const char *version, const char *upload_data,
  57                                       size_t *upload_data_size, void **con_cls)
  58 {
  59         HTTPD *httpd = (HTTPD *)cls;
  60         return httpd->answer_to_connection(connection, url, method, version, upload_data, upload_data_size, con_cls);
  61 }
  62
  63 int HTTPD::answer_to_connection(MHD_Connection *connection,
  64                                 const char *url, const char *method,
  65                                 const char *version, const char *upload_data,
  66                                 size_t *upload_data_size, void **con_cls)
  67 {
  68         // See if the URL ends in “.metacube”.
  69         HTTPD::Stream::Framing framing;
  70         if (strstr(url, ".metacube") == url + strlen(url) - strlen(".metacube")) {
  71                 framing = HTTPD::Stream::FRAMING_METACUBE;
  72         } else {
  73                 framing = HTTPD::Stream::FRAMING_RAW;
  74         }
  75
  76         HTTPD::Stream *stream = new HTTPD::Stream(this, framing);
  77         stream->add_data(header.data(), header.size(), Stream::DATA_TYPE_HEADER);
  78         {
  79                 unique_lock<mutex> lock(streams_mutex);
  80                 streams.insert(stream);
  81         }
  82         *con_cls = stream;
  83
  84         // Does not strictly have to be equal to MUX_BUFFER_SIZE.
  85         MHD_Response *response = MHD_create_response_from_callback(
  86                 (size_t)-1, MUX_BUFFER_SIZE, &HTTPD::Stream::reader_callback_thunk, stream, &HTTPD::free_stream);
  87
  88         // TODO: Content-type?
  89         if (framing == HTTPD::Stream::FRAMING_METACUBE) {
  90                 MHD_add_response_header(response, "Content-encoding", "metacube");
  91         }
  92         int ret = MHD_queue_response(connection, MHD_HTTP_OK, response);
  93         MHD_destroy_response(response);  // Only decreases the refcount; actual free is after the request is done.
  94
  95         return ret;
  96 }
  97
  98 void HTTPD::free_stream(void *cls)
  99 {
 100         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 101         HTTPD *httpd = stream->get_parent();
 102         {
 103                 unique_lock<mutex> lock(httpd->streams_mutex);
 104                 delete stream;
 105                 httpd->streams.erase(stream);
 106         }
 107 }
 108
 109 ssize_t HTTPD::Stream::reader_callback_thunk(void *cls, uint64_t pos, char *buf, size_t max)
 110 {
 111         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 112         return stream->reader_callback(pos, buf, max);
 113 }
 114
 115 ssize_t HTTPD::Stream::reader_callback(uint64_t pos, char *buf, size_t max)
 116 {
 117         unique_lock<mutex> lock(buffer_mutex);
 118         has_buffered_data.wait(lock, [this]{ return should_quit || !buffered_data.empty(); });
 119         if (should_quit) {
 120                 return 0;
 121         }
 122
 123         ssize_t ret = 0;
 124         while (max > 0 && !buffered_data.empty()) {
 125                 const string &s = buffered_data.front();
 126                 assert(s.size() > used_of_buffered_data);
 127                 size_t len = s.size() - used_of_buffered_data;
 128                 if (max >= len) {
 129                         // Consume the entire (rest of the) string.
 130                         memcpy(buf, s.data() + used_of_buffered_data, len);
 131                         buf += len;
 132                         ret += len;
 133                         max -= len;
 134                         buffered_data.pop_front();
 135                         used_of_buffered_data = 0;
 136                 } else {
 137                         // We don't need the entire string; just use the first part of it.
 138                         memcpy(buf, s.data() + used_of_buffered_data, max);
 139                         buf += max;
 140                         used_of_buffered_data += max;
 141                         ret += max;
 142                         max = 0;
 143                 }
 144         }
 145
 146         return ret;
 147 }
 148
 149 void HTTPD::Stream::add_data(const char *buf, size_t buf_size, HTTPD::Stream::DataType data_type)
 150 {
 151         if (buf_size == 0) {
 152                 return;
 153         }
 154         if (data_type == DATA_TYPE_KEYFRAME) {
 155                 seen_keyframe = true;
 156         } else if (data_type == DATA_TYPE_OTHER && !seen_keyframe) {
 157                 // Start sending only once we see a keyframe.
 158                 return;
 159         }
 160
 161         unique_lock<mutex> lock(buffer_mutex);
 162
 163         if (framing == FRAMING_METACUBE) {
 164                 metacube2_block_header hdr;
 165                 memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
 166                 hdr.size = htonl(buf_size);
 167                 int flags = 0;
 168                 if (data_type == DATA_TYPE_HEADER) {
 169                         flags |= METACUBE_FLAGS_HEADER;
 170                 } else if (data_type == DATA_TYPE_OTHER) {
 171                         flags |= METACUBE_FLAGS_NOT_SUITABLE_FOR_STREAM_START;
 172                 }
 173                 hdr.flags = htons(flags);
 174                 hdr.csum = htons(metacube2_compute_crc(&hdr));
 175                 buffered_data.emplace_back((char *)&hdr, sizeof(hdr));
 176         }
 177         buffered_data.emplace_back(buf, buf_size);
 178
 179         // Send a Metacube2 timestamp every keyframe.
 180         if (framing == FRAMING_METACUBE && data_type == DATA_TYPE_KEYFRAME) {
 181                 timespec now;
 182                 clock_gettime(CLOCK_REALTIME, &now);
 183
 184                 metacube2_timestamp_packet packet;
 185                 packet.type = htobe64(METACUBE_METADATA_TYPE_ENCODER_TIMESTAMP);
 186                 packet.tv_sec = htobe64(now.tv_sec);
 187                 packet.tv_nsec = htobe64(now.tv_nsec);
 188
 189                 metacube2_block_header hdr;
 190                 memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
 191                 hdr.size = htonl(sizeof(packet));
 192                 hdr.flags = htons(METACUBE_FLAGS_METADATA);
 193                 hdr.csum = htons(metacube2_compute_crc(&hdr));
 194                 buffered_data.emplace_back((char *)&hdr, sizeof(hdr));
 195                 buffered_data.emplace_back((char *)&packet, sizeof(packet));
 196         }
 197
 198         has_buffered_data.notify_all();
 199 }
 200
 201 void HTTPD::Stream::stop()
 202 {
 203         unique_lock<mutex> lock(buffer_mutex);
 204         should_quit = true;
 205         has_buffered_data.notify_all();
 206 }