#include <assert.h>
#include <errno.h>
+#include <limits.h>
#include <netinet/in.h>
+#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
+#include <algorithm>
#include <string>
+#include <queue>
#include <vector>
#include "log.h"
-#include "metacube.h"
+#include "metacube2.h"
+#include "mutexlock.h"
#include "state.pb.h"
#include "stream.h"
#include "util.h"
using namespace std;
-Stream::Stream(const string &url, size_t backlog_size, Encoding encoding)
+Stream::Stream(const string &url, size_t backlog_size, size_t prebuffering_bytes, Encoding encoding)
: url(url),
encoding(encoding),
data_fd(make_tempfile("")),
backlog_size(backlog_size),
+ prebuffering_bytes(prebuffering_bytes),
bytes_received(0),
- mark_pool(NULL)
+ pacing_rate(~0U)
{
if (data_fd == -1) {
exit(1);
}
+
+ pthread_mutex_init(&queued_data_mutex, NULL);
}
Stream::~Stream()
encoding(Stream::STREAM_ENCODING_RAW), // Will be changed later.
data_fd(data_fd),
backlog_size(serialized.backlog_size()),
+ prebuffering_bytes(serialized.prebuffering_bytes()),
bytes_received(serialized.bytes_received()),
- mark_pool(NULL)
+ pacing_rate(~0U)
{
if (data_fd == -1) {
exit(1);
}
- // Split old-style headers into HTTP and video headers.
- if (!serialized.header().empty()) {
- string header = serialized.header();
- size_t split = header.find("\r\n\r\n");
- if (split == string::npos) {
- http_header = header;
- stream_header = "";
- } else {
- http_header = header.substr(0, split + 2); // Split off the second \r\n.
- stream_header = header.substr(split, string::npos);
+ 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);
}
StreamProto Stream::serialize()
serialized.set_stream_header(stream_header);
serialized.add_data_fds(data_fd);
serialized.set_backlog_size(backlog_size);
+ serialized.set_prebuffering_bytes(prebuffering_bytes);
serialized.set_bytes_received(bytes_received);
+ 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();
- iovec iov;
- iov.iov_base = const_cast<char *>(existing_data.data());
- iov.iov_len = existing_data.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<iovec> iovs;
- iovs.push_back(iov);
- add_data_raw(iovs);
+ vector<DataElement> data_elements;
+ data_elements.push_back(data_element);
+ add_data_raw(data_elements);
+ remove_obsolete_starting_points();
}
void Stream::put_client_to_sleep(Client *client)
}
// Return a new set of iovecs that contains only the first <bytes_wanted> bytes of <data>.
-vector<iovec> collect_iovecs(const vector<iovec> &data, size_t bytes_wanted)
+vector<iovec> collect_iovecs(const vector<Stream::DataElement> &data, size_t bytes_wanted)
{
vector<iovec> ret;
- for (size_t i = 0; i < data.size() && bytes_wanted > 0; ++i) {
- if (data[i].iov_len <= bytes_wanted) {
+ size_t max_iovecs = std::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.
- ret.push_back(data[i]);
- bytes_wanted -= data[i].iov_len;
+ ret.push_back(data[i].data);
+ bytes_wanted -= data[i].data.iov_len;
} else {
// Take only parts of this iovec.
iovec iov;
- iov.iov_base = data[i].iov_base;
- iov.iov_len = bytes_wanted;
+ iov.iov_base = data[i].data.iov_base;
+ iov.iov_len = bytes_wanted;
ret.push_back(iov);
bytes_wanted = 0;
}
}
// Return a new set of iovecs that contains all of <data> except the first <bytes_wanted> bytes.
-vector<iovec> remove_iovecs(const vector<iovec> &data, size_t bytes_wanted)
+vector<Stream::DataElement> remove_iovecs(const vector<Stream::DataElement> &data, size_t bytes_wanted)
{
- vector<iovec> ret;
+ vector<Stream::DataElement> ret;
size_t i;
for (i = 0; i < data.size() && bytes_wanted > 0; ++i) {
- if (data[i].iov_len <= bytes_wanted) {
+ if (data[i].data.iov_len <= bytes_wanted) {
// Consume the entire iovec.
- bytes_wanted -= data[i].iov_len;
+ bytes_wanted -= data[i].data.iov_len;
} else {
// Take only parts of this iovec.
- iovec iov;
- iov.iov_base = reinterpret_cast<char *>(data[i].iov_base) + bytes_wanted;
- iov.iov_len = data[i].iov_len - bytes_wanted;
- ret.push_back(iov);
+ Stream::DataElement data_element;
+ data_element.data.iov_base = reinterpret_cast<char *>(data[i].data.iov_base) + bytes_wanted;
+ data_element.data.iov_len = data[i].data.iov_len - bytes_wanted;
+ data_element.suitable_for_stream_start = NOT_SUITABLE_FOR_STREAM_START;
+ ret.push_back(data_element);
bytes_wanted = 0;
}
}
return ret;
}
-void Stream::add_data_raw(const vector<iovec> &orig_data)
+void Stream::add_data_raw(const vector<DataElement> &orig_data)
{
- vector<iovec> data = orig_data;
+ vector<DataElement> data = orig_data;
while (!data.empty()) {
size_t pos = bytes_received % backlog_size;
}
}
-void Stream::add_data_deferred(const char *data, size_t bytes)
+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);
+ assert(suitable_for_stream_start == SUITABLE_FOR_STREAM_START ||
+ suitable_for_stream_start == NOT_SUITABLE_FOR_STREAM_START);
+
+ DataElement data_element;
+ data_element.suitable_for_stream_start = suitable_for_stream_start;
+
if (encoding == Stream::STREAM_ENCODING_METACUBE) {
// Add a Metacube block header before the data.
- metacube_block_header hdr;
- memcpy(hdr.sync, METACUBE_SYNC, sizeof(hdr.sync));
+ metacube2_block_header hdr;
+ memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
hdr.size = htonl(bytes);
- hdr.flags = htonl(0);
+ hdr.flags = htons(0);
+ if (suitable_for_stream_start == NOT_SUITABLE_FOR_STREAM_START) {
+ hdr.flags |= htons(METACUBE_FLAGS_NOT_SUITABLE_FOR_STREAM_START);
+ }
+ hdr.csum = htons(metacube2_compute_crc(&hdr));
- iovec iov;
- iov.iov_base = new char[bytes + sizeof(hdr)];
- iov.iov_len = bytes + sizeof(hdr);
+ data_element.data.iov_base = new char[bytes + sizeof(hdr)];
+ data_element.data.iov_len = bytes + sizeof(hdr);
- memcpy(iov.iov_base, &hdr, sizeof(hdr));
- memcpy(reinterpret_cast<char *>(iov.iov_base) + sizeof(hdr), data, bytes);
+ memcpy(data_element.data.iov_base, &hdr, sizeof(hdr));
+ memcpy(reinterpret_cast<char *>(data_element.data.iov_base) + sizeof(hdr), data, bytes);
- queued_data.push_back(iov);
+ queued_data.push_back(data_element);
} else if (encoding == Stream::STREAM_ENCODING_RAW) {
// Just add the data itself.
- iovec iov;
- iov.iov_base = new char[bytes];
- memcpy(iov.iov_base, data, bytes);
- iov.iov_len = bytes;
+ data_element.data.iov_base = new char[bytes];
+ memcpy(data_element.data.iov_base, data, bytes);
+ data_element.data.iov_len = bytes;
- queued_data.push_back(iov);
+ queued_data.push_back(data_element);
} else {
assert(false);
}
void Stream::process_queued_data()
{
- if (queued_data.empty()) {
- return;
+ std::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.
+ {
+ MutexLock lock(&queued_data_mutex);
+ if (queued_data.empty()) {
+ return;
+ }
+
+ swap(queued_data, queued_data_copy);
+ }
+
+ // 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) {
+ 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);
- for (size_t i = 0; i < queued_data.size(); ++i) {
- char *data = reinterpret_cast<char *>(queued_data[i].iov_base);
+ 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;
}
- queued_data.clear();
// We have more data, so wake up all clients.
if (to_process.empty()) {