-#include <stdio.h>
-#include <unistd.h>
+#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 "metacube2.h"
+#include "state.pb.h"
#include "stream.h"
#include "util.h"
-#include "state.pb.h"
using namespace std;
-Stream::Stream(const string &stream_id, size_t backlog_size)
- : stream_id(stream_id),
+Stream::Stream(const string &url, size_t backlog_size, size_t prebuffering_bytes, Encoding encoding, Encoding src_encoding)
+ : url(url),
+ encoding(encoding),
+ src_encoding(src_encoding),
data_fd(make_tempfile("")),
backlog_size(backlog_size),
- bytes_received(0),
- mark_pool(NULL)
+ prebuffering_bytes(prebuffering_bytes)
{
if (data_fd == -1) {
exit(1);
Stream::~Stream()
{
if (data_fd != -1) {
- int ret;
- do {
- ret = close(data_fd);
- } while (ret == -1 && errno == EINTR);
- if (ret == -1) {
- perror("close");
- }
+ safe_close(data_fd);
}
}
-Stream::Stream(const StreamProto &serialized)
- : stream_id(serialized.stream_id()),
- header(serialized.header()),
- data_fd(make_tempfile(serialized.data())),
+Stream::Stream(const StreamProto &serialized, int data_fd)
+ : url(serialized.url()),
+ http_header(serialized.http_header()),
+ stream_header(serialized.stream_header()),
+ encoding(Stream::STREAM_ENCODING_RAW), // Will be changed later.
+ data_fd(data_fd),
backlog_size(serialized.backlog_size()),
- bytes_received(serialized.bytes_received()),
- mark_pool(NULL)
+ prebuffering_bytes(serialized.prebuffering_bytes()),
+ bytes_received(serialized.bytes_received())
{
if (data_fd == -1) {
exit(1);
}
+
+ for (ssize_t point : serialized.suitable_starting_point()) {
+ 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);
+ }
}
StreamProto Stream::serialize()
{
StreamProto serialized;
- serialized.set_header(header);
- if (!read_tempfile(data_fd, serialized.mutable_data())) { // Closes data_fd.
- exit(1);
- }
+ serialized.set_http_header(http_header);
+ 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);
- serialized.set_stream_id(stream_id);
+ for (size_t point : suitable_starting_points) {
+ serialized.add_suitable_starting_point(point);
+ }
+ serialized.set_url(url);
data_fd = -1;
return serialized;
}
+
+void Stream::set_backlog_size(size_t new_size)
+{
+ if (backlog_size == new_size) {
+ return;
+ }
+
+ string existing_data;
+ if (!read_tempfile_and_close(data_fd, &existing_data)) {
+ exit(1);
+ }
+
+ // Unwrap the data so it's no longer circular.
+ if (bytes_received <= backlog_size) {
+ existing_data.resize(bytes_received);
+ } else {
+ size_t pos = bytes_received % backlog_size;
+ existing_data = existing_data.substr(pos, string::npos) +
+ existing_data.substr(0, pos);
+ }
+
+ // See if we need to discard data.
+ if (new_size < existing_data.size()) {
+ size_t to_discard = existing_data.size() - new_size;
+ existing_data = existing_data.substr(to_discard, string::npos);
+ }
+
+ // Create a new, empty data file.
+ data_fd = make_tempfile("");
+ if (data_fd == -1) {
+ exit(1);
+ }
+ backlog_size = new_size;
+
+ // Now cheat a bit by rewinding, and adding all the old data back.
+ bytes_received -= 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.metacube_flags = 0; // Ignored by add_data_raw().
+
+ 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)
{
sleeping_clients.push_back(client);
}
-void Stream::wake_up_all_clients()
+// Return a new set of iovecs that contains only the first <bytes_wanted> bytes of <data>.
+vector<iovec> collect_iovecs(const vector<Stream::DataElement> &data, size_t bytes_wanted)
+{
+ vector<iovec> ret;
+ 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.
+ 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].data.iov_base;
+ iov.iov_len = bytes_wanted;
+ ret.push_back(iov);
+ bytes_wanted = 0;
+ }
+ }
+ return ret;
+}
+
+// Return a new set of iovecs that contains all of <data> except the first <bytes_wanted> bytes.
+vector<Stream::DataElement> remove_iovecs(const vector<Stream::DataElement> &data, size_t bytes_wanted)
+{
+ vector<Stream::DataElement> ret;
+ size_t i;
+ for (i = 0; i < data.size() && bytes_wanted > 0; ++i) {
+ if (data[i].data.iov_len <= bytes_wanted) {
+ // Consume the entire iovec.
+ bytes_wanted -= data[i].data.iov_len;
+ } else {
+ // Take only parts of this iovec.
+ 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.metacube_flags = METACUBE_FLAGS_NOT_SUITABLE_FOR_STREAM_START;
+ ret.push_back(data_element);
+ bytes_wanted = 0;
+ }
+ }
+
+ // Add the rest of the iovecs unchanged.
+ ret.insert(ret.end(), data.begin() + i, data.end());
+ return ret;
+}
+
+void Stream::add_data_raw(const vector<DataElement> &orig_data)
+{
+ vector<DataElement> data = orig_data;
+ while (!data.empty()) {
+ size_t pos = bytes_received % backlog_size;
+
+ // Collect as many iovecs as we can before we hit the point
+ // where the circular buffer wraps around.
+ vector<iovec> to_write = collect_iovecs(data, backlog_size - pos);
+ ssize_t ret;
+ do {
+ ret = pwritev(data_fd, to_write.data(), to_write.size(), pos);
+ } while (ret == -1 && errno == EINTR);
+
+ if (ret == -1) {
+ log_perror("pwritev");
+ // Dazed and confused, but trying to continue...
+ return;
+ }
+ bytes_received += ret;
+
+ // Remove the data that was actually written from the set of iovecs.
+ data = remove_iovecs(data, ret);
+ }
+}
+
+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, uint16_t metacube_flags)
+{
+ // For regular output, we don't want to send the client twice
+ // (it's already sent out together with the HTTP header).
+ // However, for Metacube output, we need to send it so that
+ // the Cubemap instance in the other end has a chance to update it.
+ // It may come twice in its stream, but Cubemap doesn't care.
+ if (encoding == Stream::STREAM_ENCODING_RAW &&
+ (metacube_flags & METACUBE_FLAGS_HEADER) != 0) {
+ return;
+ }
+
+ lock_guard<mutex> lock(queued_data_mutex);
+
+ DataElement data_element;
+ data_element.metacube_flags = metacube_flags;
+
+ if (encoding == Stream::STREAM_ENCODING_METACUBE) {
+ // Add a Metacube block header before the data.
+ metacube2_block_header hdr;
+ memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
+ hdr.size = htonl(bytes);
+ 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);
+
+ 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(data_element);
+ } else if (encoding == Stream::STREAM_ENCODING_RAW) {
+ // Just add the data itself.
+ 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(data_element);
+ } else {
+ assert(false);
+ }
+}
+
+void Stream::process_queued_data()
{
+ 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.
+ {
+ lock_guard<mutex> 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 (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();
+ 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 += elem.data.iov_len;
+ }
+
+ add_data_raw(queued_data_copy);
+ remove_obsolete_starting_points();
+ for (const DataElement &elem : queued_data_copy) {
+ char *data = reinterpret_cast<char *>(elem.data.iov_base);
+ delete[] data;
+ }
+
+ // We have more data, so wake up all clients.
if (to_process.empty()) {
swap(sleeping_clients, to_process);
} else {
projects / cubemap / blobdiff