X-Git-Url: https://git.sesse.net/?p=cubemap;a=blobdiff_plain;f=stream.cpp;h=64bf2e8053e7c0edd79b17f43ba12160a3dd8795;hp=2b9a69593a478605800fd21c9585063eebec8d0c;hb=b757a4a2ce9d24835b52a185134835762af2f50c;hpb=8cc780cf37063ce29f13380976a54dd8302fe3a9

diff --git a/stream.cpp b/stream.cpp
index 2b9a695..64bf2e8 100644
--- a/stream.cpp
+++ b/stream.cpp
@@ -1,65 +1,90 @@
+#include <assert.h>
 #include <errno.h>
+#include <limits.h>
+#include <netinet/in.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <unistd.h>
+#include <string.h>
+#include <sys/types.h>
+#include <algorithm>
 #include <string>
+#include <queue>
 #include <vector>
 
-#include "state.pb.h"
 #include "log.h"
+#include "metacube2.h"
+#include "mutexlock.h"
+#include "state.pb.h"
 #include "stream.h"
 #include "util.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)
+	: 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()
 {
 	if (data_fd != -1) {
-		int ret;
-		do {
-			ret = close(data_fd);
-		} while (ret == -1 && errno == EINTR);
-		if (ret == -1) {
-			log_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()),
+	  prebuffering_bytes(serialized.prebuffering_bytes()),
 	  bytes_received(serialized.bytes_received()),
-	  mark_pool(NULL)
+	  pacing_rate(~0U)
 {
 	if (data_fd == -1) {
 		exit(1);
 	}
+
+	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()
 {
 	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 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;
 }
@@ -71,7 +96,7 @@ void Stream::set_backlog_size(size_t new_size)
 	}
 
 	string existing_data;
-	if (!read_tempfile(data_fd, &existing_data)) {  // Closes data_fd.
+	if (!read_tempfile_and_close(data_fd, &existing_data)) {
 		exit(1);
 	}
 
@@ -92,11 +117,22 @@ void Stream::set_backlog_size(size_t new_size)
 
 	// 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();
-	add_data(existing_data.data(), 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<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)
@@ -104,49 +140,173 @@ void Stream::put_client_to_sleep(Client *client)
 	sleeping_clients.push_back(client);
 }
 
-void Stream::add_data(const char *data, ssize_t bytes)
+// 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)
 {
-	size_t pos = bytes_received % backlog_size;
-	bytes_received += bytes;
-
-	if (pos + bytes > backlog_size) {
-		ssize_t to_copy = backlog_size - pos;
-		while (to_copy > 0) {
-			int ret = pwrite(data_fd, data, to_copy, pos);
-			if (ret == -1 && errno == EINTR) {
-				continue;
-			}
-			if (ret == -1) {
-				log_perror("pwrite");
-				// Dazed and confused, but trying to continue...
-				break;
-			}
-			pos += ret;
-			data += ret;
-			to_copy -= ret;
-			bytes -= ret;
+	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;
 		}
-		pos = 0;
 	}
+	return ret;
+}
 
-	while (bytes > 0) {
-		int ret = pwrite(data_fd, data, bytes, pos);
-		if (ret == -1 && errno == EINTR) {
-			continue;
+// 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.suitable_for_stream_start = 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("pwrite");
+			log_perror("pwritev");
 			// Dazed and confused, but trying to continue...
-			break;
+			return;
 		}
-		pos += ret;
-		data += ret;
-		bytes -= ret;
+		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::wake_up_all_clients()
+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.
+		metacube2_block_header hdr;
+		memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
+		hdr.size = htonl(bytes);
+		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));
+
+		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.
+	{
+		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_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;
+	}
+
+	// We have more data, so wake up all clients.
 	if (to_process.empty()) {
 		swap(sleeping_clients, to_process);
 	} else {