moonfire-nvr/src/uuid.h

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// This file is part of Moonfire NVR, a security camera network video recorder.
// Copyright (C) 2016 Lamb <slamb@slamb.org>
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// In addition, as a special exception, the copyright holders give
// permission to link the code of portions of this program with the
// OpenSSL library under certain conditions as described in each
// individual source file, and distribute linked combinations including
// the two.
//
// You must obey the GNU General Public License in all respects for all
// of the code used other than OpenSSL. If you modify file(s) with this
// exception, you may extend this exception to your version of the
// file(s), but you are not obligated to do so. If you do not wish to do
// so, delete this exception statement from your version. If you delete
// this exception statement from all source files in the program, then
// also delete it here.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
//
// uuid.h: small wrapper around the C UUID library for generating/parsing
// RFC 4122 UUIDs.
#ifndef MOONFIRE_NVR_UUID_H
#define MOONFIRE_NVR_UUID_H
Write using the shiny new schema There's a lot of work left to do on this: * important latency optimization: the recording threads block while fsync()ing sample files, which can take 250+ ms. This should be moved to a separate thread to happen asynchronously. * write cycle optimizations: several SQLite commits per camera per minute. * test coverage: this drops testing of the file rotation, and there are several error paths worth testing. * ffmpeg oddities to investigate: * the out-of-order first frame's pts * measurable delay before returning packets * it sometimes returns an initial packet it calls a "key" frame that actually has an SEI recovery point NAL but not an IDR-coded slice NAL, even though in the input these always seem to come together. This makes playback starting from this recording not work at all on Chrome. The symptom is that it loads a player-looking thing with the proper dimensions but playback never actually starts. I imagine these are all related but haven't taken the time to dig through ffmpeg code and understand them. The right thing anyway may be to ditch ffmpeg for RTSP streaming (perhaps in favor of the live555 library), as it seems to have other omissions like making it hard/impossible to take advantage of Sender Reports. In the meantime, I attempted to mitigate problems by decreasing ffmpeg's probesize. * handling overlapping recordings: right now if there's too much time drift or a time jump, you can end up with recordings that the UI won't play without manual database changes. It's not obvious what the right thing to do is. * easy camera setup: currently you have to manually insert rows in the SQLite database and restart. but I think it's best to get something in to iterate from. This deletes a lot of code, including: * the ffmpeg video sink code (instead now using a bit of extra code in Stream on top of the SampleFileWriter, SampleIndexEncoder, and MoonfireDatabase code that's been around for a while) * FileManager (in favor of new code using the database) * the old UI * RealFile and friends * the dependency on protocol buffers, which was used for the config file (though I'll likely have other reasons for using protocol buffers later) * even some utilities like IsWord that were just for validating the config
2016-02-03 23:22:37 -08:00
#include <gmock/gmock.h>
#include <re2/stringpiece.h>
#include <uuid/uuid.h>
namespace moonfire_nvr {
class Uuid {
public:
// Create a null uuid.
Uuid() { uuid_clear(me_); }
// Parse the text UUID. Returns success.
bool ParseText(re2::StringPiece input);
// Parse a binary UUID. In practice any 16-byte string is considered valid.
bool ParseBinary(re2::StringPiece input);
// Return a 36-byte lowercase text representation, such as
// 1b4e28ba-2fa1-11d2-883f-0016d3cca427.
std::string UnparseText() const;
// Return a reference to the 16-byte binary form.
// Invalidated by any change to the Uuid object.
re2::StringPiece binary_view() const;
bool operator==(const Uuid &) const;
bool operator<(const Uuid &) const;
bool is_null() const { return uuid_is_null(me_); }
private:
friend class RealUuidGenerator;
uuid_t me_;
};
class UuidGenerator {
public:
virtual ~UuidGenerator() {}
virtual Uuid Generate() = 0;
};
Write using the shiny new schema There's a lot of work left to do on this: * important latency optimization: the recording threads block while fsync()ing sample files, which can take 250+ ms. This should be moved to a separate thread to happen asynchronously. * write cycle optimizations: several SQLite commits per camera per minute. * test coverage: this drops testing of the file rotation, and there are several error paths worth testing. * ffmpeg oddities to investigate: * the out-of-order first frame's pts * measurable delay before returning packets * it sometimes returns an initial packet it calls a "key" frame that actually has an SEI recovery point NAL but not an IDR-coded slice NAL, even though in the input these always seem to come together. This makes playback starting from this recording not work at all on Chrome. The symptom is that it loads a player-looking thing with the proper dimensions but playback never actually starts. I imagine these are all related but haven't taken the time to dig through ffmpeg code and understand them. The right thing anyway may be to ditch ffmpeg for RTSP streaming (perhaps in favor of the live555 library), as it seems to have other omissions like making it hard/impossible to take advantage of Sender Reports. In the meantime, I attempted to mitigate problems by decreasing ffmpeg's probesize. * handling overlapping recordings: right now if there's too much time drift or a time jump, you can end up with recordings that the UI won't play without manual database changes. It's not obvious what the right thing to do is. * easy camera setup: currently you have to manually insert rows in the SQLite database and restart. but I think it's best to get something in to iterate from. This deletes a lot of code, including: * the ffmpeg video sink code (instead now using a bit of extra code in Stream on top of the SampleFileWriter, SampleIndexEncoder, and MoonfireDatabase code that's been around for a while) * FileManager (in favor of new code using the database) * the old UI * RealFile and friends * the dependency on protocol buffers, which was used for the config file (though I'll likely have other reasons for using protocol buffers later) * even some utilities like IsWord that were just for validating the config
2016-02-03 23:22:37 -08:00
class MockUuidGenerator : public UuidGenerator {
public:
MOCK_METHOD0(Generate, Uuid());
};
UuidGenerator *GetRealUuidGenerator();
} // namespace moonfire_nvr
#endif // MOONFIRE_NVR_CODING_H