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
  14 #include "defs.h"
  15 #include "metacube2.h"
  16
  17 struct MHD_Connection;
  18 struct MHD_Response;
  19
  20 using namespace std;
  21
  22 HTTPD::HTTPD()
  23 {
  24 }
  25
  26 HTTPD::~HTTPD()
  27 {
  28         if (mhd) {
  29                 MHD_quiesce_daemon(mhd);
  30                 for (Stream *stream : streams) {
  31                         stream->stop();
  32                 }
  33                 MHD_stop_daemon(mhd);
  34         }
  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::add_data(const char *buf, size_t size, bool keyframe)
  51 {
  52         unique_lock<mutex> lock(streams_mutex);
  53         for (Stream *stream : streams) {
  54                 stream->add_data(buf, size, keyframe ? Stream::DATA_TYPE_KEYFRAME : Stream::DATA_TYPE_OTHER);
  55         }
  56 }
  57
  58 int HTTPD::answer_to_connection_thunk(void *cls, MHD_Connection *connection,
  59                                       const char *url, const char *method,
  60                                       const char *version, const char *upload_data,
  61                                       size_t *upload_data_size, void **con_cls)
  62 {
  63         HTTPD *httpd = (HTTPD *)cls;
  64         return httpd->answer_to_connection(connection, url, method, version, upload_data, upload_data_size, con_cls);
  65 }
  66
  67 int HTTPD::answer_to_connection(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         // See if the URL ends in “.metacube”.
  73         HTTPD::Stream::Framing framing;
  74         if (strstr(url, ".metacube") == url + strlen(url) - strlen(".metacube")) {
  75                 framing = HTTPD::Stream::FRAMING_METACUBE;
  76         } else {
  77                 framing = HTTPD::Stream::FRAMING_RAW;
  78         }
  79
  80         HTTPD::Stream *stream = new HTTPD::Stream(this, framing);
  81         stream->add_data(header.data(), header.size(), Stream::DATA_TYPE_HEADER);
  82         {
  83                 unique_lock<mutex> lock(streams_mutex);
  84                 streams.insert(stream);
  85         }
  86         *con_cls = stream;
  87
  88         // Does not strictly have to be equal to MUX_BUFFER_SIZE.
  89         MHD_Response *response = MHD_create_response_from_callback(
  90                 (size_t)-1, MUX_BUFFER_SIZE, &HTTPD::Stream::reader_callback_thunk, stream, &HTTPD::free_stream);
  91
  92         // TODO: Content-type?
  93         if (framing == HTTPD::Stream::FRAMING_METACUBE) {
  94                 MHD_add_response_header(response, "Content-encoding", "metacube");
  95         }
  96         int ret = MHD_queue_response(connection, MHD_HTTP_OK, response);
  97         MHD_destroy_response(response);  // Only decreases the refcount; actual free is after the request is done.
  98
  99         return ret;
 100 }
 101
 102 void HTTPD::free_stream(void *cls)
 103 {
 104         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 105         HTTPD *httpd = stream->get_parent();
 106         {
 107                 unique_lock<mutex> lock(httpd->streams_mutex);
 108                 delete stream;
 109                 httpd->streams.erase(stream);
 110         }
 111 }
 112
 113 ssize_t HTTPD::Stream::reader_callback_thunk(void *cls, uint64_t pos, char *buf, size_t max)
 114 {
 115         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 116         return stream->reader_callback(pos, buf, max);
 117 }
 118
 119 ssize_t HTTPD::Stream::reader_callback(uint64_t pos, char *buf, size_t max)
 120 {
 121         unique_lock<mutex> lock(buffer_mutex);
 122         has_buffered_data.wait(lock, [this]{ return should_quit || !buffered_data.empty(); });
 123         if (should_quit) {
 124                 return 0;
 125         }
 126
 127         ssize_t ret = 0;
 128         while (max > 0 && !buffered_data.empty()) {
 129                 const string &s = buffered_data.front();
 130                 assert(s.size() > used_of_buffered_data);
 131                 size_t len = s.size() - used_of_buffered_data;
 132                 if (max >= len) {
 133                         // Consume the entire (rest of the) string.
 134                         memcpy(buf, s.data() + used_of_buffered_data, len);
 135                         buf += len;
 136                         ret += len;
 137                         max -= len;
 138                         buffered_data.pop_front();
 139                         used_of_buffered_data = 0;
 140                 } else {
 141                         // We don't need the entire string; just use the first part of it.
 142                         memcpy(buf, s.data() + used_of_buffered_data, max);
 143                         buf += max;
 144                         used_of_buffered_data += max;
 145                         ret += max;
 146                         max = 0;
 147                 }
 148         }
 149
 150         return ret;
 151 }
 152
 153 void HTTPD::Stream::add_data(const char *buf, size_t buf_size, HTTPD::Stream::DataType data_type)
 154 {
 155         if (buf_size == 0) {
 156                 return;
 157         }
 158         if (data_type == DATA_TYPE_KEYFRAME) {
 159                 seen_keyframe = true;
 160         } else if (data_type == DATA_TYPE_OTHER && !seen_keyframe) {
 161                 // Start sending only once we see a keyframe.
 162                 return;
 163         }
 164
 165         unique_lock<mutex> lock(buffer_mutex);
 166
 167         if (framing == FRAMING_METACUBE) {
 168                 metacube2_block_header hdr;
 169                 memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
 170                 hdr.size = htonl(buf_size);
 171                 int flags = 0;
 172                 if (data_type == DATA_TYPE_HEADER) {
 173                         flags |= METACUBE_FLAGS_HEADER;
 174                 } else if (data_type == DATA_TYPE_OTHER) {
 175                         flags |= METACUBE_FLAGS_NOT_SUITABLE_FOR_STREAM_START;
 176                 }
 177                 hdr.flags = htons(flags);
 178                 hdr.csum = htons(metacube2_compute_crc(&hdr));
 179                 buffered_data.emplace_back((char *)&hdr, sizeof(hdr));
 180         }
 181         buffered_data.emplace_back(buf, buf_size);
 182
 183         // Send a Metacube2 timestamp every keyframe.
 184         if (framing == FRAMING_METACUBE && data_type == DATA_TYPE_KEYFRAME) {
 185                 timespec now;
 186                 clock_gettime(CLOCK_REALTIME, &now);
 187
 188                 metacube2_timestamp_packet packet;
 189                 packet.type = htobe64(METACUBE_METADATA_TYPE_ENCODER_TIMESTAMP);
 190                 packet.tv_sec = htobe64(now.tv_sec);
 191                 packet.tv_nsec = htobe64(now.tv_nsec);
 192
 193                 metacube2_block_header hdr;
 194                 memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
 195                 hdr.size = htonl(sizeof(packet));
 196                 hdr.flags = htons(METACUBE_FLAGS_METADATA);
 197                 hdr.csum = htons(metacube2_compute_crc(&hdr));
 198                 buffered_data.emplace_back((char *)&hdr, sizeof(hdr));
 199                 buffered_data.emplace_back((char *)&packet, sizeof(packet));
 200         }
 201
 202         has_buffered_data.notify_all();
 203 }
 204
 205 void HTTPD::Stream::stop()
 206 {
 207         unique_lock<mutex> lock(buffer_mutex);
 208         should_quit = true;
 209         has_buffered_data.notify_all();
 210 }