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 void HTTPD::start(int port)
  27 {
  28         MHD_start_daemon(MHD_USE_THREAD_PER_CONNECTION | MHD_USE_POLL_INTERNALLY | MHD_USE_DUAL_STACK,
  29                          port,
  30                          nullptr, nullptr,
  31                          &answer_to_connection_thunk, this,
  32                          MHD_OPTION_NOTIFY_COMPLETED, &request_completed_thunk, this,
  33                          MHD_OPTION_END);
  34 }
  35
  36 void HTTPD::add_data(const char *buf, size_t size, bool keyframe)
  37 {
  38         unique_lock<mutex> lock(streams_mutex);
  39         for (Stream *stream : streams) {
  40                 stream->add_data(buf, size, keyframe ? Stream::DATA_TYPE_KEYFRAME : Stream::DATA_TYPE_OTHER);
  41         }
  42 }
  43
  44 int HTTPD::answer_to_connection_thunk(void *cls, MHD_Connection *connection,
  45                                       const char *url, const char *method,
  46                                       const char *version, const char *upload_data,
  47                                       size_t *upload_data_size, void **con_cls)
  48 {
  49         HTTPD *httpd = (HTTPD *)cls;
  50         return httpd->answer_to_connection(connection, url, method, version, upload_data, upload_data_size, con_cls);
  51 }
  52
  53 int HTTPD::answer_to_connection(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         // See if the URL ends in “.metacube”.
  59         HTTPD::Stream::Framing framing;
  60         if (strstr(url, ".metacube") == url + strlen(url) - strlen(".metacube")) {
  61                 framing = HTTPD::Stream::FRAMING_METACUBE;
  62         } else {
  63                 framing = HTTPD::Stream::FRAMING_RAW;
  64         }
  65
  66         HTTPD::Stream *stream = new HTTPD::Stream(framing);
  67         stream->add_data(header.data(), header.size(), Stream::DATA_TYPE_HEADER);
  68         {
  69                 unique_lock<mutex> lock(streams_mutex);
  70                 streams.insert(stream);
  71         }
  72         *con_cls = stream;
  73
  74         // Does not strictly have to be equal to MUX_BUFFER_SIZE.
  75         MHD_Response *response = MHD_create_response_from_callback(
  76                 (size_t)-1, MUX_BUFFER_SIZE, &HTTPD::Stream::reader_callback_thunk, stream, &HTTPD::free_stream);
  77
  78         // TODO: Content-type?
  79         if (framing == HTTPD::Stream::FRAMING_METACUBE) {
  80                 MHD_add_response_header(response, "Content-encoding", "metacube");
  81         }
  82         int ret = MHD_queue_response(connection, MHD_HTTP_OK, response);
  83         //MHD_destroy_response(response);
  84
  85         return ret;
  86 }
  87
  88 void HTTPD::free_stream(void *cls)
  89 {
  90         // FIXME: When is this actually called, if ever?
  91         // Also, shouldn't we remove it from streams?
  92         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
  93         delete stream;
  94 }
  95
  96 void HTTPD::request_completed_thunk(void *cls, struct MHD_Connection *connection, void **con_cls, enum MHD_RequestTerminationCode toe)
  97 {
  98         HTTPD *httpd = (HTTPD *)cls;
  99         return httpd->request_completed(connection, con_cls, toe);
 100 }
 101
 102 void HTTPD::request_completed(struct MHD_Connection *connection, void **con_cls, enum MHD_RequestTerminationCode toe)
 103 {
 104         if (con_cls == nullptr) {
 105                 // Request was never set up.
 106                 return;
 107         }
 108         HTTPD::Stream *stream = (HTTPD::Stream *)*con_cls;
 109         {
 110                 unique_lock<mutex> lock(streams_mutex);
 111                 delete stream;
 112                 streams.erase(stream);
 113         }
 114 }
 115
 116 ssize_t HTTPD::Stream::reader_callback_thunk(void *cls, uint64_t pos, char *buf, size_t max)
 117 {
 118         HTTPD::Stream *stream = (HTTPD::Stream *)cls;
 119         return stream->reader_callback(pos, buf, max);
 120 }
 121
 122 ssize_t HTTPD::Stream::reader_callback(uint64_t pos, char *buf, size_t max)
 123 {
 124         unique_lock<mutex> lock(buffer_mutex);
 125         has_buffered_data.wait(lock, [this]{ return !buffered_data.empty(); });
 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         has_buffered_data.notify_all();
 183 }
 184