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 #include "metrics.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         if (strcmp(url, "/metrics") == 0) {
  82                 string contents = global_metrics.serialize();
  83                 MHD_Response *response = MHD_create_response_from_buffer(
  84                         contents.size(), &contents[0], MHD_RESPMEM_MUST_COPY);
  85                 MHD_add_response_header(response, "Content-type", "text/plain");
  86                 int ret = MHD_queue_response(connection, MHD_HTTP_OK, response);
  87                 MHD_destroy_response(response);  // Only decreases the refcount; actual free is after the request is done.
  88                 return ret;
  89         }
  90
  91         HTTPD::Stream *stream = new HTTPD::Stream(this, framing);
  92         stream->add_data(header.data(), header.size(), Stream::DATA_TYPE_HEADER);
  93         {
  94                 unique_lock<mutex> lock(streams_mutex);
  95                 streams.insert(stream);
  96         }
  97         *con_cls = stream;
  98
  99         // Does not strictly have to be equal to MUX_BUFFER_SIZE.
 100         MHD_Response *response = MHD_create_response_from_callback(
 101                 (size_t)-1, MUX_BUFFER_SIZE, &HTTPD::Stream::reader_callback_thunk, stream, &HTTPD::free_stream);
 102         // TODO: Content-type?
 103         if (framing == HTTPD::Stream::FRAMING_METACUBE) {
 104                 MHD_add_response_header(response, "Content-encoding", "metacube");
 105         }
 106
 107         int ret = MHD_queue_response(connection, MHD_HTTP_OK, response);
 108         MHD_destroy_response(response);  // Only decreases the refcount; actual free is after the request is done.
 109
 110         return ret;
 111 }
 112
 113 void HTTPD::free_stream(void *cls)
 114 {
 115         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 116         HTTPD *httpd = stream->get_parent();
 117         {
 118                 unique_lock<mutex> lock(httpd->streams_mutex);
 119                 delete stream;
 120                 httpd->streams.erase(stream);
 121         }
 122 }
 123
 124 ssize_t HTTPD::Stream::reader_callback_thunk(void *cls, uint64_t pos, char *buf, size_t max)
 125 {
 126         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 127         return stream->reader_callback(pos, buf, max);
 128 }
 129
 130 ssize_t HTTPD::Stream::reader_callback(uint64_t pos, char *buf, size_t max)
 131 {
 132         unique_lock<mutex> lock(buffer_mutex);
 133         has_buffered_data.wait(lock, [this]{ return should_quit || !buffered_data.empty(); });
 134         if (should_quit) {
 135                 return 0;
 136         }
 137
 138         ssize_t ret = 0;
 139         while (max > 0 && !buffered_data.empty()) {
 140                 const string &s = buffered_data.front();
 141                 assert(s.size() > used_of_buffered_data);
 142                 size_t len = s.size() - used_of_buffered_data;
 143                 if (max >= len) {
 144                         // Consume the entire (rest of the) string.
 145                         memcpy(buf, s.data() + used_of_buffered_data, len);
 146                         buf += len;
 147                         ret += len;
 148                         max -= len;
 149                         buffered_data.pop_front();
 150                         used_of_buffered_data = 0;
 151                 } else {
 152                         // We don't need the entire string; just use the first part of it.
 153                         memcpy(buf, s.data() + used_of_buffered_data, max);
 154                         buf += max;
 155                         used_of_buffered_data += max;
 156                         ret += max;
 157                         max = 0;
 158                 }
 159         }
 160
 161         return ret;
 162 }
 163
 164 void HTTPD::Stream::add_data(const char *buf, size_t buf_size, HTTPD::Stream::DataType data_type)
 165 {
 166         if (buf_size == 0) {
 167                 return;
 168         }
 169         if (data_type == DATA_TYPE_KEYFRAME) {
 170                 seen_keyframe = true;
 171         } else if (data_type == DATA_TYPE_OTHER && !seen_keyframe) {
 172                 // Start sending only once we see a keyframe.
 173                 return;
 174         }
 175
 176         unique_lock<mutex> lock(buffer_mutex);
 177
 178         if (framing == FRAMING_METACUBE) {
 179                 metacube2_block_header hdr;
 180                 memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
 181                 hdr.size = htonl(buf_size);
 182                 int flags = 0;
 183                 if (data_type == DATA_TYPE_HEADER) {
 184                         flags |= METACUBE_FLAGS_HEADER;
 185                 } else if (data_type == DATA_TYPE_OTHER) {
 186                         flags |= METACUBE_FLAGS_NOT_SUITABLE_FOR_STREAM_START;
 187                 }
 188                 hdr.flags = htons(flags);
 189                 hdr.csum = htons(metacube2_compute_crc(&hdr));
 190                 buffered_data.emplace_back((char *)&hdr, sizeof(hdr));
 191         }
 192         buffered_data.emplace_back(buf, buf_size);
 193
 194         // Send a Metacube2 timestamp every keyframe.
 195         if (framing == FRAMING_METACUBE && data_type == DATA_TYPE_KEYFRAME) {
 196                 timespec now;
 197                 clock_gettime(CLOCK_REALTIME, &now);
 198
 199                 metacube2_timestamp_packet packet;
 200                 packet.type = htobe64(METACUBE_METADATA_TYPE_ENCODER_TIMESTAMP);
 201                 packet.tv_sec = htobe64(now.tv_sec);
 202                 packet.tv_nsec = htobe64(now.tv_nsec);
 203
 204                 metacube2_block_header hdr;
 205                 memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
 206                 hdr.size = htonl(sizeof(packet));
 207                 hdr.flags = htons(METACUBE_FLAGS_METADATA);
 208                 hdr.csum = htons(metacube2_compute_crc(&hdr));
 209                 buffered_data.emplace_back((char *)&hdr, sizeof(hdr));
 210                 buffered_data.emplace_back((char *)&packet, sizeof(packet));
 211         }
 212
 213         has_buffered_data.notify_all();
 214 }
 215
 216 void HTTPD::Stream::stop()
 217 {
 218         unique_lock<mutex> lock(buffer_mutex);
 219         should_quit = true;
 220         has_buffered_data.notify_all();
 221 }