#include <sys/types.h>
#include <algorithm>
#include <string>
+#include <queue>
#include <vector>
#include "log.h"
backlog_size(backlog_size),
prebuffering_bytes(prebuffering_bytes),
bytes_received(0),
- last_suitable_starting_point(-1),
pacing_rate(~0U)
{
if (data_fd == -1) {
exit(1);
}
- assert(serialized.has_last_suitable_starting_point());
- last_suitable_starting_point = serialized.last_suitable_starting_point();
+ for (int i = 0; i < serialized.suitable_starting_point_size(); ++i) {
+ ssize_t point = serialized.suitable_starting_point(i);
+ if (point == -1) {
+ // Can happen when upgrading from before 1.1.3,
+ // where this was an optional field with -1 signifying
+ // "no such point".
+ continue;
+ }
+ suitable_starting_points.push_back(point);
+ }
pthread_mutex_init(&queued_data_mutex, NULL);
}
serialized.set_backlog_size(backlog_size);
serialized.set_prebuffering_bytes(prebuffering_bytes);
serialized.set_bytes_received(bytes_received);
- serialized.set_last_suitable_starting_point(last_suitable_starting_point);
+ for (size_t i = 0; i < suitable_starting_points.size(); ++i) {
+ serialized.add_suitable_starting_point(suitable_starting_points[i]);
+ }
serialized.set_url(url);
data_fd = -1;
return serialized;
// Now cheat a bit by rewinding, and adding all the old data back.
bytes_received -= existing_data.size();
-
- size_t bytes_before_suitable_starting_point;
- if (last_suitable_starting_point == -1) {
- bytes_before_suitable_starting_point = existing_data.size();
- } else if (size_t(last_suitable_starting_point) < backlog_size) {
- bytes_before_suitable_starting_point = 0;
- } else {
- bytes_before_suitable_starting_point = last_suitable_starting_point - backlog_size;
- }
+ DataElement data_element;
+ data_element.data.iov_base = const_cast<char *>(existing_data.data());
+ data_element.data.iov_len = existing_data.size();
+ data_element.suitable_for_stream_start = NOT_SUITABLE_FOR_STREAM_START; // Ignored by add_data_raw().
vector<DataElement> data_elements;
- if (bytes_before_suitable_starting_point > 0) {
- // There's really no usable data here (except for ?backlog=1 users),
- // but we need to get the accounting right anyway.
- DataElement data_element;
- data_element.data.iov_base = const_cast<char *>(existing_data.data());
- data_element.data.iov_len = bytes_before_suitable_starting_point;
- data_element.suitable_for_stream_start = NOT_SUITABLE_FOR_STREAM_START;
- data_elements.push_back(data_element);
- }
- if (bytes_before_suitable_starting_point < existing_data.size()) {
- DataElement data_element;
- data_element.data.iov_base = const_cast<char *>(existing_data.data() + bytes_before_suitable_starting_point);
- data_element.data.iov_len = existing_data.size() - bytes_before_suitable_starting_point;
- data_element.suitable_for_stream_start = SUITABLE_FOR_STREAM_START;
- data_elements.push_back(data_element);
- }
-
- last_suitable_starting_point = -1;
+ data_elements.push_back(data_element);
add_data_raw(data_elements);
+ remove_obsolete_starting_points();
}
void Stream::put_client_to_sleep(Client *client)
vector<iovec> collect_iovecs(const vector<Stream::DataElement> &data, size_t bytes_wanted)
{
vector<iovec> ret;
- size_t max_iovecs = std::min<size_t>(data.size(), IOV_MAX);
+ size_t max_iovecs = min<size_t>(data.size(), IOV_MAX);
for (size_t i = 0; i < max_iovecs && bytes_wanted > 0; ++i) {
if (data[i].data.iov_len <= bytes_wanted) {
// Consume the entire iovec.
}
}
+void Stream::remove_obsolete_starting_points()
+{
+ // We could do a binary search here (std::lower_bound), but it seems
+ // overkill for removing what's probably only a few points.
+ while (!suitable_starting_points.empty() &&
+ bytes_received - suitable_starting_points[0] > backlog_size) {
+ suitable_starting_points.pop_front();
+ }
+}
+
void Stream::add_data_deferred(const char *data, size_t bytes, StreamStartSuitability suitable_for_stream_start)
{
MutexLock lock(&queued_data_mutex);
void Stream::process_queued_data()
{
- std::vector<DataElement> queued_data_copy;
+ vector<DataElement> queued_data_copy;
// Hold the lock for as short as possible, since add_data_raw() can possibly
// write to disk, which might disturb the input thread.
swap(queued_data, queued_data_copy);
}
- // Update the last suitable starting point for the stream,
- // if the queued data contains such a starting point.
+ // Add suitable starting points for the stream, if the queued data
+ // contains such starting points. Note that we drop starting points
+ // if they're less than 10 kB apart, so that we don't get a huge
+ // amount of them for e.g. each and every MPEG-TS 188-byte cell.
+ // The 10 kB value is somewhat arbitrary, but at least it should make
+ // the RAM cost of saving the position ~0.1% (or less) of the actual
+ // 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;
for (size_t i = 0; i < queued_data_copy.size(); ++i) {
if (queued_data_copy[i].suitable_for_stream_start == SUITABLE_FOR_STREAM_START) {
- last_suitable_starting_point = byte_position;
+ size_t num_points = suitable_starting_points.size();
+ if (num_points >= 2 &&
+ suitable_starting_points[num_points - 1] - suitable_starting_points[num_points - 2] < minimum_start_point_distance) {
+ // p[n-1] - p[n-2] < 10 kB, so drop p[n-1].
+ suitable_starting_points.pop_back();
+ }
+ suitable_starting_points.push_back(byte_position);
}
byte_position += queued_data_copy[i].data.iov_len;
}
add_data_raw(queued_data_copy);
+ remove_obsolete_starting_points();
for (size_t i = 0; i < queued_data_copy.size(); ++i) {
char *data = reinterpret_cast<char *>(queued_data_copy[i].data.iov_base);
delete[] data;