vlc | branch: master | Rémi Denis-Courmont <[email protected]> | Wed Oct 13 18:57:58 2010 +0300| [59fb10d033cd01b6d5c2379a20982cc0216f9b22] | committer: Rémi Denis-Courmont
Add atomic swap and compare-and-swap > http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=59fb10d033cd01b6d5c2379a20982cc0216f9b22 --- include/vlc_atomic.h | 3 +++ src/libvlccore.sym | 2 ++ src/misc/atomic.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ src/win32/atomic.c | 19 +++++++++++++++++++ 4 files changed, 68 insertions(+), 0 deletions(-) diff --git a/include/vlc_atomic.h b/include/vlc_atomic.h index 51acccc..770e47a 100644 --- a/include/vlc_atomic.h +++ b/include/vlc_atomic.h @@ -47,4 +47,7 @@ static inline uintptr_t vlc_atomic_dec (vlc_atomic_t *atom) return vlc_atomic_sub (atom, 1); } +VLC_EXPORT(uintptr_t, vlc_atomic_swap, (vlc_atomic_t *, uintptr_t)); +VLC_EXPORT(uintptr_t, vlc_atomic_compare_swap, (vlc_atomic_t *, uintptr_t, uintptr_t)); + #endif diff --git a/src/libvlccore.sym b/src/libvlccore.sym index 413ab79..5632223 100644 --- a/src/libvlccore.sym +++ b/src/libvlccore.sym @@ -503,6 +503,8 @@ VLC_Compiler vlc_atomic_get vlc_atomic_set vlc_atomic_add +vlc_atomic_swap +vlc_atomic_compare_swap vlc_cond_broadcast vlc_cond_destroy vlc_cond_init diff --git a/src/misc/atomic.c b/src/misc/atomic.c index 1f97f59..e0319f5 100644 --- a/src/misc/atomic.c +++ b/src/misc/atomic.c @@ -46,6 +46,24 @@ uintptr_t vlc_atomic_add (vlc_atomic_t *atom, uintptr_t v) return __sync_add_and_fetch (&atom->u, v); } +uintptr_t vlc_atomic_swap (vlc_atomic_t *atom, uintptr_t v) +{ + /* grmbl, gcc does not provide an intrinsic for this! */ + uintptr_t u; + + do + u = vlc_atomic_get (atom); + while (vlc_atomic_compare_swap (atom, u, v) != u); + + return u; +} + +uintptr_t vlc_atomic_compare_swap (vlc_atomic_t *atom, + uintptr_t oldval, uintptr_t newval) +{ + return __sync_val_compare_and_swap (&atom->u, oldval, newval); +} + #else /* Worst-case fallback implementation with a mutex */ @@ -78,4 +96,30 @@ uintptr_t vlc_atomic_add (vlc_atomic_t *atom, uintptr_t v) return v; } +uintptr_t vlc_atomic_swap (vlc_atomic_t *atom, uintptr_t v) +{ + uintptr_t u; + + vlc_mutex_lock (&lock); + u = atom->u; + atom->u = v; + vlc_mutex_unlock (&lock); + + return u; +} + +uintptr_t vlc_atomic_compare_and_swap (vlc_atomic_t *atom, + uintptr_t oldval, uintptr_t newval) +{ + uintptr_t u; + + vlc_mutex_lock (&lock); + u = atom->u; + if (u == oldval) + atom->u = newval; + vlc_mutex_unlock (&lock); + + return u; +} + #endif diff --git a/src/win32/atomic.c b/src/win32/atomic.c index abadf89..14687e6 100644 --- a/src/win32/atomic.c +++ b/src/win32/atomic.c @@ -50,3 +50,22 @@ uintptr_t vlc_atomic_add (vlc_atomic_t *atom, uintptr_t v) return InterlockedExchangeAdd (&atom->s, v) + v; #endif } + +uintptr_t vlc_atomic_swap (vlc_atomic_t *atom, uintptr_t v) +{ +#if defined (WIN64) + return InterlockedExchange64 (&atom->s, v); +#else + return InterlockedExchange (&atom->s, v); +#endif +} + +uintptr_t vlc_atomic_compare_swap (vlc_atomic_t *atom, + uintptr_t oldval, uintptr_t newval) +{ +#if defined (WIN64) + return InterlockedCompareExchange64 (&atom->s, newval, oldval); +#else + return InterlockedCompareExchange (&atom->s, newval, oldval); +#endif +} _______________________________________________ vlc-commits mailing list [email protected] http://mailman.videolan.org/listinfo/vlc-commits
