X-Git-Url: https://git.sesse.net/?p=cubemap;a=blobdiff_plain;f=stream.cpp;fp=stream.cpp;h=62c7507cc796b4075ece559fb00564b0ce46229e;hp=0b494fb8d5527d4ba51290d62b109ad510f4cc9a;hb=20e85bd6901355cc40a6cfb4c0deb7232d9aa63f;hpb=061988af511f42da3cd584b4d983177504ddc177 diff --git a/stream.cpp b/stream.cpp index 0b494fb..62c7507 100644 --- a/stream.cpp +++ b/stream.cpp @@ -1,6 +1,7 @@ #include #include #include +#include #include #include #include @@ -19,13 +20,23 @@ using namespace std; -Stream::Stream(const string &url, size_t backlog_size, size_t prebuffering_bytes, Encoding encoding, Encoding src_encoding) +Stream::Stream(const string &url, + size_t backlog_size, + size_t prebuffering_bytes, + Encoding encoding, + Encoding src_encoding, + unsigned hls_frag_duration, + size_t hls_backlog_margin, + const std::string &allow_origin) : url(url), encoding(encoding), src_encoding(src_encoding), + allow_origin(allow_origin), data_fd(make_tempfile("")), - backlog_size(backlog_size), - prebuffering_bytes(prebuffering_bytes) + backlog_size(backlog_size), + prebuffering_bytes(prebuffering_bytes), + hls_frag_duration(hls_frag_duration), + hls_backlog_margin(hls_backlog_margin) { if (data_fd == -1) { exit(1); @@ -46,7 +57,9 @@ Stream::Stream(const StreamProto &serialized, int data_fd) encoding(Stream::STREAM_ENCODING_RAW), // Will be changed later. data_fd(data_fd), backlog_size(serialized.backlog_size()), - bytes_received(serialized.bytes_received()) + bytes_received(serialized.bytes_received()), + first_fragment_index(serialized.first_fragment_index()), + discontinuity_counter(serialized.discontinuity_counter()) { if (data_fd == -1) { exit(1); @@ -61,6 +74,10 @@ Stream::Stream(const StreamProto &serialized, int data_fd) } suitable_starting_points.push_back(point); } + + for (const FragmentStartProto &fragment : serialized.fragment()) { + fragments.push_back(FragmentStart { size_t(fragment.byte_position()), fragment.pts() }); + } } StreamProto Stream::serialize() @@ -74,6 +91,14 @@ StreamProto Stream::serialize() for (size_t point : suitable_starting_points) { serialized.add_suitable_starting_point(point); } + for (const FragmentStart &fragment : fragments) { + FragmentStartProto *proto = serialized.add_fragment(); + proto->set_byte_position(fragment.byte_position); + proto->set_pts(fragment.pts); + } + serialized.set_first_fragment_index(first_fragment_index); + serialized.set_discontinuity_counter(discontinuity_counter); + serialized.set_url(url); data_fd = -1; return serialized; @@ -167,6 +192,7 @@ vector remove_iovecs(const vector &dat data_element.data.iov_base = reinterpret_cast(data[i].data.iov_base) + bytes_wanted; data_element.data.iov_len = data[i].data.iov_len - bytes_wanted; data_element.metacube_flags = METACUBE_FLAGS_NOT_SUITABLE_FOR_STREAM_START; + data_element.pts = RationalPTS(); ret.push_back(data_element); bytes_wanted = 0; } @@ -211,9 +237,16 @@ void Stream::remove_obsolete_starting_points() bytes_received - suitable_starting_points[0] > backlog_size) { suitable_starting_points.pop_front(); } + assert(backlog_size >= hls_backlog_margin); + while (!fragments.empty() && + bytes_received - fragments[0].byte_position > (backlog_size - hls_backlog_margin)) { + fragments.pop_front(); + ++first_fragment_index; + clear_hls_playlist_cache(); + } } -void Stream::add_data_deferred(const char *data, size_t bytes, uint16_t metacube_flags) +void Stream::add_data_deferred(const char *data, size_t bytes, uint16_t metacube_flags, const RationalPTS &pts) { // For regular output, we don't want to send the client twice // (it's already sent out together with the HTTP header). @@ -229,8 +262,23 @@ void Stream::add_data_deferred(const char *data, size_t bytes, uint16_t metacube DataElement data_element; data_element.metacube_flags = metacube_flags; + data_element.pts = pts; if (encoding == Stream::STREAM_ENCODING_METACUBE) { + // Construct a PTS metadata block. (We'll avoid sending it out + // if we don't have a valid PTS.) + metacube2_pts_packet pts_packet; + pts_packet.type = htobe64(METACUBE_METADATA_TYPE_NEXT_BLOCK_PTS); + pts_packet.pts = htobe64(pts.pts); + pts_packet.timebase_num = htobe64(pts.timebase_num); + pts_packet.timebase_den = htobe64(pts.timebase_den); + + metacube2_block_header pts_hdr; + memcpy(pts_hdr.sync, METACUBE2_SYNC, sizeof(pts_hdr.sync)); + pts_hdr.size = htonl(sizeof(pts_packet)); + pts_hdr.flags = htons(METACUBE_FLAGS_METADATA); + pts_hdr.csum = htons(metacube2_compute_crc(&pts_hdr)); + // Add a Metacube block header before the data. metacube2_block_header hdr; memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync)); @@ -238,11 +286,23 @@ void Stream::add_data_deferred(const char *data, size_t bytes, uint16_t metacube hdr.flags = htons(metacube_flags); hdr.csum = htons(metacube2_compute_crc(&hdr)); - data_element.data.iov_base = new char[bytes + sizeof(hdr)]; data_element.data.iov_len = bytes + sizeof(hdr); + if (pts.timebase_num != 0) { + data_element.data.iov_len += sizeof(pts_hdr) + sizeof(pts_packet); + } + data_element.data.iov_base = new char[data_element.data.iov_len]; + + char *ptr = reinterpret_cast(data_element.data.iov_base); + if (pts.timebase_num != 0) { + memcpy(ptr, &pts_hdr, sizeof(pts_hdr)); + ptr += sizeof(pts_hdr); + memcpy(ptr, &pts_packet, sizeof(pts_packet)); + ptr += sizeof(pts_packet); + } - memcpy(data_element.data.iov_base, &hdr, sizeof(hdr)); - memcpy(reinterpret_cast(data_element.data.iov_base) + sizeof(hdr), data, bytes); + memcpy(ptr, &hdr, sizeof(hdr)); + ptr += sizeof(hdr); + memcpy(ptr, data, bytes); queued_data.push_back(data_element); } else if (encoding == Stream::STREAM_ENCODING_RAW) { @@ -281,6 +341,7 @@ void Stream::process_queued_data() // data, and 10 kB is a very fine granularity in most streams. static const int minimum_start_point_distance = 10240; size_t byte_position = bytes_received; + bool need_hls_clear = false; for (const DataElement &elem : queued_data_copy) { if ((elem.metacube_flags & METACUBE_FLAGS_NOT_SUITABLE_FOR_STREAM_START) == 0) { size_t num_points = suitable_starting_points.size(); @@ -290,9 +351,16 @@ void Stream::process_queued_data() suitable_starting_points.pop_back(); } suitable_starting_points.push_back(byte_position); + + if (elem.pts.timebase_num != 0) { + need_hls_clear |= add_fragment_boundary(byte_position, elem.pts); + } } byte_position += elem.data.iov_len; } + if (need_hls_clear) { + clear_hls_playlist_cache(); + } add_data_raw(queued_data_copy); remove_obsolete_starting_points(); @@ -309,3 +377,96 @@ void Stream::process_queued_data() sleeping_clients.clear(); } } + +bool Stream::add_fragment_boundary(size_t byte_position, const RationalPTS &pts) +{ + double pts_double = double(pts.pts) * pts.timebase_den / pts.timebase_num; + + if (fragments.size() <= 1) { + // Just starting up, so try to establish the first in-progress fragment. + fragments.push_back(FragmentStart{ byte_position, pts_double }); + return false; + } + + // Keep extending the in-progress fragment as long as we do not + // exceed the target duration by more than half a second + // (RFC 8216 4.3.3.1) and we get closer to the target by doing so. + // Note that in particular, this means we'll always extend + // as long as we don't exceed the target duration. + double current_duration = fragments[fragments.size() - 1].pts; + double candidate_duration = pts_double - fragments[fragments.size() - 2].pts; + if (lrintf(candidate_duration) <= hls_frag_duration && + fabs(candidate_duration - hls_frag_duration) < fabs(current_duration - hls_frag_duration)) { + fragments.back() = FragmentStart{ byte_position, pts_double }; + return false; + } else { + // Extending the in-progress fragment would make it too long, + // so finalize it and start a new in-progress fragment. + fragments.push_back(FragmentStart{ byte_position, pts_double }); + return true; + } +} + +void Stream::clear_hls_playlist_cache() +{ + hls_playlist_http10.reset(); + hls_playlist_http11_close.reset(); + hls_playlist_http11_persistent.reset(); +} + +shared_ptr Stream::generate_hls_playlist(bool http_11, bool close_after_response) +{ + char buf[256]; + snprintf(buf, sizeof(buf), + "#EXTM3U\r\n" + "#EXT-X-VERSION:7\r\n" + "#EXT-X-TARGETDURATION:%u\r\n" + "#EXT-X-MEDIA-SEQUENCE:%zu\r\n" + "#EXT-X-DISCONTINUITY-SEQUENCE:%zu\r\n", + hls_frag_duration, + first_fragment_index, + discontinuity_counter); + + string playlist = buf; + + if (!stream_header.empty()) { + snprintf(buf, sizeof(buf), "#EXT-X-MAP:URI=\"%s?frag=header\"\r\n", url.c_str()); + playlist += buf; + } + + playlist += "\r\n"; + if (fragments.size() >= 3) { + for (size_t i = 0; i < fragments.size() - 2; ++i) { + char buf[256]; + snprintf(buf, sizeof(buf), "#EXTINF:%f,\r\n%s?frag=%zu-%zu\r\n", + fragments[i + 1].pts - fragments[i].pts, + url.c_str(), + fragments[i].byte_position, + fragments[i + 1].byte_position); + playlist += buf; + } + } + + string response; + if (http_11) { + response = "HTTP/1.1 200 OK\r\n"; + if (close_after_response) { + response.append("Connection: close\r\n"); + } + } else { + assert(close_after_response); + response = "HTTP/1.0 200 OK\r\n"; + } + snprintf(buf, sizeof(buf), "Content-length: %zu\r\n", playlist.size()); + response.append(buf); + response.append("Content-type: application/x-mpegURL\r\n"); + if (!allow_origin.empty()) { + response.append("Access-Control-Allow-Origin: "); + response.append(allow_origin); + response.append("\r\n"); + } + response.append("\r\n"); + response.append(move(playlist)); + + return shared_ptr(new string(move(response))); +}