}
Stream *stream = client->stream;
- if (client->stream_pos == size_t(-2)) {
+ if (client->stream_pos == Client::STREAM_POS_AT_START) {
// Start sending from the beginning of the backlog.
client->stream_pos = min<size_t>(
stream->bytes_received - stream->backlog_size,
0);
client->state = Client::SENDING_DATA;
goto sending_data;
+ } else if (client->stream_pos_end != Client::STREAM_POS_NO_END) {
+ // We're sending a fragment, and should have all of it,
+ // so start sending right away.
+ assert(client->stream_pos >= 0);
+ client->state = Client::SENDING_DATA;
+ goto sending_data;
} else if (stream->prebuffering_bytes == 0) {
// Start sending from the first keyframe we get. In other
// words, we won't send any of the backlog, but we'll start
// sending immediately as we get the next keyframe block.
// Note that this is functionally identical to the next if branch,
// except that we save a binary search.
+ assert(client->stream_pos == Client::STREAM_POS_AT_END);
+ assert(client->stream_pos_end == Client::STREAM_POS_NO_END);
client->stream_pos = stream->bytes_received;
client->state = Client::WAITING_FOR_KEYFRAME;
} else {
// so that we are conservative and never add extra latency over just
// waiting (assuming CBR or nearly so); otherwise, we could want e.g.
// 100 kB prebuffer but end up sending a 10 MB GOP.
+ assert(client->stream_pos == Client::STREAM_POS_AT_END);
+ assert(client->stream_pos_end == Client::STREAM_POS_NO_END);
deque<size_t>::const_iterator starting_point_it =
lower_bound(stream->suitable_starting_points.begin(),
stream->suitable_starting_points.end(),
Stream *stream = client->stream;
sending_data_again:
- size_t bytes_to_send = stream->bytes_received - client->stream_pos;
+ size_t bytes_to_send;
+ if (client->stream_pos_end == Client::STREAM_POS_NO_END) {
+ bytes_to_send = stream->bytes_received - client->stream_pos;
+ } else {
+ bytes_to_send = client->stream_pos_end - client->stream_pos;
+ }
assert(bytes_to_send <= stream->backlog_size);
if (bytes_to_send == 0) {
+ if (client->stream_pos == client->stream_pos_end) { // We have a definite end, and we're at it.
+ if (more_requests(client)) {
+ // We're done sending the fragment, but should keep on reading new requests.
+ goto read_request_again;
+ } else {
+ // We're done sending the fragment, so now close.
+ // This is postcondition #1.
+ close_client(client);
+ }
+ }
return;
}
client->stream_pos += ret;
client->bytes_sent += ret;
- if (client->stream_pos == stream->bytes_received) {
+ assert(client->stream_pos_end == Client::STREAM_POS_NO_END || client->stream_pos <= client->stream_pos_end);
+ if (client->stream_pos == client->stream_pos_end) {
+ goto sending_data_again; // Will see that bytes_to_send == 0 and end.
+ } else if (client->stream_pos == stream->bytes_received) {
// We don't have any more data for this client, so put it to sleep.
// This is postcondition #3.
stream->put_client_to_sleep(client);
} else if (more_data && size_t(ret) == bytes_to_send) {
goto sending_data_again;
}
+ // We'll also get here for postcondition #4 (similar to the EAGAIN path above).
break;
}
default:
size_t bytes_to_send = stream->bytes_received - client->stream_pos;
if (bytes_to_send > stream->backlog_size) {
size_t bytes_lost = bytes_to_send - stream->backlog_size;
- client->stream_pos = stream->bytes_received - stream->backlog_size;
client->bytes_lost += bytes_lost;
++client->num_loss_events;
+ if (!client->close_after_response) {
+ assert(client->stream_pos_end != Client::STREAM_POS_NO_END);
+
+ // We've already sent a Content-length, so we can't just skip data.
+ // Close the connection immediately and hope the other side
+ // is able to figure out that there was an error and it needs to skip.
+ client->close_after_response = true;
+ client->stream_pos = client->stream_pos_end;
+ } else {
+ client->stream_pos = stream->bytes_received - stream->backlog_size;
+ }
}
}
string url = request_tokens[1];
client->url = url;
if (url.size() > 8 && url.find("?backlog") == url.size() - 8) {
- client->stream_pos = -2;
+ client->stream_pos = Client::STREAM_POS_AT_START;
url = url.substr(0, url.size() - 8);
} else {
- client->stream_pos = -1;
+ size_t pos = url.find("?frag=");
+ if (pos != string::npos) {
+ // Parse an endpoint of the type /stream.mp4?frag=1234-5678.
+ const char *ptr = url.c_str() + pos + 6;
+
+ // "?frag=header" is special.
+ if (strcmp(ptr, "header") == 0) {
+ client->stream_pos = Client::STREAM_POS_HEADER_ONLY;
+ client->stream_pos_end = -1;
+ } else {
+ char *endptr;
+ long long frag_start = strtol(ptr, &endptr, 10);
+ if (ptr == endptr || frag_start < 0 || frag_start == LLONG_MAX) {
+ return 400; // Bad request.
+ }
+ if (*endptr != '-') {
+ return 400; // Bad request.
+ }
+ ptr = endptr + 1;
+
+ long long frag_end = strtol(ptr, &endptr, 10);
+ if (ptr == endptr || frag_end < frag_start || frag_end == LLONG_MAX) {
+ return 400; // Bad request.
+ }
+
+ if (*endptr != '\0') {
+ return 400; // Bad request.
+ }
+
+ client->stream_pos = frag_start;
+ client->stream_pos_end = frag_end;
+ }
+ url = url.substr(0, pos);
+ } else {
+ client->stream_pos = -1;
+ client->stream_pos_end = -1;
+ }
}
// Figure out if we're supposed to close the socket after we've delivered the response.
return 503; // Service unavailable.
}
- // Streams currently never end, so we don't have a content-length,
- // and can just as well tell the client it's Connection: close
- // (otherwise, we'd have to implement chunking TE for no good reason).
- // When we start to support fragments, this will change.
- client->close_after_response = true;
+ if (client->stream_pos_end == Client::STREAM_POS_NO_END) {
+ // This stream won't end, so we don't have a content-length,
+ // and can just as well tell the client it's Connection: close
+ // (otherwise, we'd have to implement chunking TE for no good reason).
+ client->close_after_response = true;
+ } else {
+ if (stream->encoding == Stream::STREAM_ENCODING_METACUBE) {
+ // This doesn't make any sense, and is hard to implement, too.
+ return 416; // Range not satisfiable.
+ }
+
+ // Check that we have the requested fragment in our backlog.
+ size_t buffer_end = stream->bytes_received;
+ size_t buffer_start = (buffer_end <= stream->backlog_size) ? 0 : buffer_end - stream->backlog_size;
+
+ if (client->stream_pos_end > buffer_end ||
+ client->stream_pos < buffer_start) {
+ return 416; // Range not satisfiable.
+ }
+ }
client->stream = stream;
if (setsockopt(client->sock, SOL_SOCKET, SO_MAX_PACING_RATE, &client->stream->pacing_rate, sizeof(client->stream->pacing_rate)) == -1) {
{
Stream *stream = client->stream;
client->header_or_short_response = stream->http_header;
+ if (client->stream_pos == Client::STREAM_POS_HEADER_ONLY) {
+ char buf[64];
+ snprintf(buf, sizeof(buf), "Content-length: %zu\r\n", stream->stream_header.size());
+ client->header_or_short_response.append(buf);
+ } else if (client->stream_pos_end != Client::STREAM_POS_NO_END) {
+ char buf[64];
+ snprintf(buf, sizeof(buf), "Content-length: %zu\r\n", client->stream_pos_end - client->stream_pos);
+ client->header_or_short_response.append(buf);
+ }
if (client->http_11) {
assert(client->header_or_short_response.find("HTTP/1.0") == 0);
client->header_or_short_response[7] = '1'; // Change to HTTP/1.1.
} else {
assert(false);
}
- client->header_or_short_response.append(stream->stream_header);
+ if (client->stream_pos == Client::STREAM_POS_HEADER_ONLY) {
+ client->state = Client::SENDING_SHORT_RESPONSE;
+ client->header_or_short_response.append(stream->stream_header);
+ } else {
+ client->state = Client::SENDING_HEADER;
+ if (client->stream_pos_end == Client::STREAM_POS_NO_END) { // Fragments don't contain stream headers.
+ client->header_or_short_response.append(stream->stream_header);
+ }
+ }
// Switch states.
- client->state = Client::SENDING_HEADER;
change_epoll_events(client, EPOLLOUT | EPOLLET | EPOLLRDHUP);
}