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

   1 #include <arpa/inet.h>
   2 #include <assert.h>
   3 #include <microhttpd.h>
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6 #include <string.h>
   7
   8 #include <vector>
   9
  10 #include "httpd.h"
  11
  12 #include "defs.h"
  13 #include "flags.h"
  14 #include "metacube2.h"
  15 #include "timebase.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         MHD_quiesce_daemon(mhd);
  29         for (Stream *stream : streams) {
  30                 stream->stop();
  31         }
  32         MHD_stop_daemon(mhd);
  33 }
  34
  35 void HTTPD::start(int port)
  36 {
  37         mhd = MHD_start_daemon(MHD_USE_THREAD_PER_CONNECTION | MHD_USE_POLL_INTERNALLY | MHD_USE_DUAL_STACK,
  38                                port,
  39                                nullptr, nullptr,
  40                                &answer_to_connection_thunk, this,
  41                                MHD_OPTION_NOTIFY_COMPLETED, nullptr, this,
  42                                MHD_OPTION_END);
  43 }
  44
  45 void HTTPD::add_data(const char *buf, size_t size, bool keyframe)
  46 {
  47         unique_lock<mutex> lock(streams_mutex);
  48         for (Stream *stream : streams) {
  49                 stream->add_data(buf, size, keyframe ? Stream::DATA_TYPE_KEYFRAME : Stream::DATA_TYPE_OTHER);
  50         }
  51 }
  52
  53 int HTTPD::answer_to_connection_thunk(void *cls, MHD_Connection *connection,
  54                                       const char *url, const char *method,
  55                                       const char *version, const char *upload_data,
  56                                       size_t *upload_data_size, void **con_cls)
  57 {
  58         HTTPD *httpd = (HTTPD *)cls;
  59         return httpd->answer_to_connection(connection, url, method, version, upload_data, upload_data_size, con_cls);
  60 }
  61
  62 int HTTPD::answer_to_connection(MHD_Connection *connection,
  63                                 const char *url, const char *method,
  64                                 const char *version, const char *upload_data,
  65                                 size_t *upload_data_size, void **con_cls)
  66 {
  67         // See if the URL ends in “.metacube”.
  68         HTTPD::Stream::Framing framing;
  69         if (strstr(url, ".metacube") == url + strlen(url) - strlen(".metacube")) {
  70                 framing = HTTPD::Stream::FRAMING_METACUBE;
  71         } else {
  72                 framing = HTTPD::Stream::FRAMING_RAW;
  73         }
  74
  75         HTTPD::Stream *stream = new HTTPD::Stream(this, framing);
  76         stream->add_data(header.data(), header.size(), Stream::DATA_TYPE_HEADER);
  77         {
  78                 unique_lock<mutex> lock(streams_mutex);
  79                 streams.insert(stream);
  80         }
  81         *con_cls = stream;
  82
  83         // Does not strictly have to be equal to MUX_BUFFER_SIZE.
  84         MHD_Response *response = MHD_create_response_from_callback(
  85                 (size_t)-1, MUX_BUFFER_SIZE, &HTTPD::Stream::reader_callback_thunk, stream, &HTTPD::free_stream);
  86
  87         // TODO: Content-type?
  88         if (framing == HTTPD::Stream::FRAMING_METACUBE) {
  89                 MHD_add_response_header(response, "Content-encoding", "metacube");
  90         }
  91         int ret = MHD_queue_response(connection, MHD_HTTP_OK, response);
  92         MHD_destroy_response(response);  // Only decreases the refcount; actual free is after the request is done.
  93
  94         return ret;
  95 }
  96
  97 void HTTPD::free_stream(void *cls)
  98 {
  99         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 100         HTTPD *httpd = stream->get_parent();
 101         {
 102                 unique_lock<mutex> lock(httpd->streams_mutex);
 103                 delete stream;
 104                 httpd->streams.erase(stream);
 105         }
 106 }
 107
 108 ssize_t HTTPD::Stream::reader_callback_thunk(void *cls, uint64_t pos, char *buf, size_t max)
 109 {
 110         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 111         return stream->reader_callback(pos, buf, max);
 112 }
 113
 114 ssize_t HTTPD::Stream::reader_callback(uint64_t pos, char *buf, size_t max)
 115 {
 116         unique_lock<mutex> lock(buffer_mutex);
 117         has_buffered_data.wait(lock, [this]{ return should_quit || !buffered_data.empty(); });
 118         if (should_quit) {
 119                 return 0;
 120         }
 121
 122         ssize_t ret = 0;
 123         while (max > 0 && !buffered_data.empty()) {
 124                 const string &s = buffered_data.front();
 125                 assert(s.size() > used_of_buffered_data);
 126                 size_t len = s.size() - used_of_buffered_data;
 127                 if (max >= len) {
 128                         // Consume the entire (rest of the) string.
 129                         memcpy(buf, s.data() + used_of_buffered_data, len);
 130                         buf += len;
 131                         ret += len;
 132                         max -= len;
 133                         buffered_data.pop_front();
 134                         used_of_buffered_data = 0;
 135                 } else {
 136                         // We don't need the entire string; just use the first part of it.
 137                         memcpy(buf, s.data() + used_of_buffered_data, max);
 138                         buf += max;
 139                         used_of_buffered_data += max;
 140                         ret += max;
 141                         max = 0;
 142                 }
 143         }
 144
 145         return ret;
 146 }
 147
 148 void HTTPD::Stream::add_data(const char *buf, size_t buf_size, HTTPD::Stream::DataType data_type)
 149 {
 150         if (buf_size == 0) {
 151                 return;
 152         }
 153         if (data_type == DATA_TYPE_KEYFRAME) {
 154                 seen_keyframe = true;
 155         } else if (data_type == DATA_TYPE_OTHER && !seen_keyframe) {
 156                 // Start sending only once we see a keyframe.
 157                 return;
 158         }
 159
 160         unique_lock<mutex> lock(buffer_mutex);
 161
 162         if (framing == FRAMING_METACUBE) {
 163                 metacube2_block_header hdr;
 164                 memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
 165                 hdr.size = htonl(buf_size);
 166                 int flags = 0;
 167                 if (data_type == DATA_TYPE_HEADER) {
 168                         flags |= METACUBE_FLAGS_HEADER;
 169                 } else if (data_type == DATA_TYPE_OTHER) {
 170                         flags |= METACUBE_FLAGS_NOT_SUITABLE_FOR_STREAM_START;
 171                 }
 172                 hdr.flags = htons(flags);
 173                 hdr.csum = htons(metacube2_compute_crc(&hdr));
 174                 buffered_data.emplace_back((char *)&hdr, sizeof(hdr));
 175         }
 176         buffered_data.emplace_back(buf, buf_size);
 177         has_buffered_data.notify_all();
 178 }
 179
 180 void HTTPD::Stream::stop()
 181 {
 182         unique_lock<mutex> lock(buffer_mutex);
 183         should_quit = true;
 184         has_buffered_data.notify_all();
 185 }