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* options: change option macros and all option declarationswm42020-03-181-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change all OPT_* macros such that they don't define the entire m_option initializer, and instead expand only to a part of it, which sets certain fields. This requires changing almost every option declaration, because they all use these macros. A declaration now always starts with {"name", ... followed by designated initializers only (possibly wrapped in macros). The OPT_* macros now initialize the .offset and .type fields only, sometimes also .priv and others. I think this change makes the option macros less tricky. The old code had to stuff everything into macro arguments (and attempted to allow setting arbitrary fields by letting the user pass designated initializers in the vararg parts). Some of this was made messy due to C99 and C11 not allowing 0-sized varargs with ',' removal. It's also possible that this change is pointless, other than cosmetic preferences. Not too happy about some things. For example, the OPT_CHOICE() indentation I applied looks a bit ugly. Much of this change was done with regex search&replace, but some places required manual editing. In particular, code in "obscure" areas (which I didn't include in compilation) might be broken now. In wayland_common.c the author of some option declarations confused the flags parameter with the default value (though the default value was also properly set below). I fixed this with this change.
* demux: add a on-disk cachewm42019-09-191-0/+323
Somewhat similar to the old --cache-file, except for the demuxer cache. Instead of keeping packet data in memory, it's written to disk and read back when needed. The idea is to reduce main memory usage, while allowing fast seeking in large cached network streams (especially live streams). Keeping the packet metadata on disk would be rather hard (would use mmap or so, or rewrite the entire demux.c packet queue handling), and since it's relatively small, just keep it in memory. Also for simplicity, the disk cache is append-only. If you're watching really long livestreams, and need pruning, you're probably out of luck. This still could be improved by trying to free unused blocks with fallocate(), but since we're writing multiple streams in an interleaved manner, this is slightly hard. Some rather gross ugliness in packet.h: we want to store the file position of the cached data somewhere, but on 32 bit architectures, we don't have any usable 64 bit members for this, just the buf/len fields, which add up to 64 bit - so the shitty union aliases this memory. Error paths untested. Side data (the complicated part of trying to serialize ffmpeg packets) untested. Stream recording had to be adjusted. Some minor details change due to this, but probably nothing important. The change in attempt_range_joining() is because packets in cache have no valid len field. It was a useful check (heuristically finding broken cases), but not a necessary one. Various other approaches were tried. It would be interesting to list them and to mention the pros and cons, but I don't feel like it.