Commit Graph

4 Commits

Author SHA1 Message Date
wm4 d87a84ca89 ring: use a different type for read/write pointers
uint_least32_t could be larger than uint32_t, so the return values of
mp_ring_get_wpos/rpos must be adjusted. Actually just use unsigned long
as type instead, because that is less awkward than uint_least32_t.
2014-05-30 02:15:25 +02:00
wm4 690ea07b7a ring: implement drain in terms of read
I think this makes it easier to reason about it and avoids duplicate
logic.
2014-05-29 02:24:05 +02:00
wm4 8e7cf4bc99 atomics: switch to C11 stdatomic.h
In my opinion, we shouldn't use atomics at all, but ok.

This switches the mpv code to use C11 stdatomic.h, and for compilers
that don't support stdatomic.h yet, we emulate the subset used by mpv
using the builtins commonly provided by gcc and clang.

This supersedes an earlier similar attempt by Kovensky. That attempt
unfortunately relied on a big copypasted freebsd header (which also
depended on much more highly compiler-specific functionality, defined
reserved symbols, etc.), so it had to be NIH'ed.

Some issues:
- C11 says default initialization of atomics "produces a valid state",
  but it's not sure whether the stored value is really 0. But we rely on
  this.
- I'm pretty sure our use of the __atomic... builtins is/was incorrect.
  We don't use atomic load/store intrinsics, and access stuff directly.
- Our wrapper actually does stricter typechecking than the stdatomic.h
  implementation by gcc 4.9. We make the atomic types incompatible with
  normal types by wrapping them into structs. (The FreeBSD wrapper does
  the same.)
- I couldn't test on MinGW.
2014-05-21 02:21:18 +02:00
wm4 0112143fda Split mpvcore/ into common/, misc/, bstr/ 2013-12-17 02:39:45 +01:00