diff options
Diffstat (limited to 'rb')
| -rw-r--r-- | rb/rb.c | 102 |
1 files changed, 89 insertions, 13 deletions
@@ -90,6 +90,36 @@ struct rb /* ========================================================================== + Calculates number of elements in ring buffer. ns stands for not safe as + in there are no checks. + ========================================================================== */ + + +static size_t rb_count_ns +( + const struct rb *rb /* rb object */ +) +{ + return (rb->head - rb->tail) & (rb->count - 1); +} + + +/* ========================================================================== + Calculates how many elements can be pushed into ring buffer. ns stands + for nos safe as in there are no checks. + ========================================================================== */ + + +static size_t rb_space_ns +( + const struct rb *rb /* rb object */ +) +{ + return (rb->tail - (rb->head + 1)) & (rb->count - 1); +} + + +/* ========================================================================== Calculates number of elements in ring buffer until the end of buffer memory. If elements don't overlap memory, function acts like rb_count ========================================================================== */ @@ -174,7 +204,7 @@ static long rb_recvs unsigned char* buf; /* buffer treated as unsigned char type */ /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/ - if (count > (rbcount = rb_count(rb))) + if (count > (rbcount = rb_count_ns(rb))) { /* * Caller requested more data then is available, adjust count @@ -271,7 +301,7 @@ static long rb_recvt pthread_mutex_lock(&rb->lock); - while (rb_count(rb) == 0 && rb->force_exit == 0) + while (rb_count_ns(rb) == 0 && rb->force_exit == 0) { struct timespec ts; /* timeout for pthread_cond_timedwait */ /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/ @@ -390,7 +420,7 @@ static long rb_sends (void)flags; - if (count > (rbspace = rb_space(rb))) + if (count > (rbspace = rb_space_ns(rb))) { /* * Caller wants to store more data then there is space available @@ -475,7 +505,7 @@ long rb_sendt pthread_mutex_lock(&rb->lock); - while (rb_space(rb) == 0 && rb->force_exit == 0) + while (rb_space_ns(rb) == 0 && rb->force_exit == 0) { struct timespec ts; /* timeout for pthread_cond_timedwait */ /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/ @@ -1015,7 +1045,7 @@ size_t rb_discard #endif cnte = rb_count_end(rb); - rbcount = rb_count(rb); + rbcount = rb_count_ns(rb); if (count > rbcount) { @@ -1072,28 +1102,74 @@ const char* rb_version /* ========================================================================== - Calculates number of elements in ring buffer + Returns number of elements in buffer. ========================================================================== */ -size_t rb_count +long rb_count ( - const struct rb *rb /* rb object */ + struct rb *rb /* rb object */ ) { - return (rb->head - rb->tail) & (rb->count - 1); + size_t count; /* number of elements in buffer */ + /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/ + + + VALID(EINVAL, rb); + VALID(EINVAL, rb->buffer); + +#if ENABLE_THREADS + if ((rb->flags & O_NONBLOCK) == 0) + { + pthread_mutex_lock(&rb->lock); + } +#endif + + count = rb_count_ns(rb); + +#if ENABLE_THREADS + if ((rb->flags & O_NONBLOCK) == 0) + { + pthread_mutex_unlock(&rb->lock); + } +#endif + + return (long)count; } /* ========================================================================== - Calculates how many elements can be pushed into ring buffer + Return number of free space in buffer ========================================================================== */ -size_t rb_space +long rb_space ( - const struct rb *rb /* rb object */ + struct rb *rb /* rb object */ ) { - return (rb->tail - (rb->head + 1)) & (rb->count - 1); + size_t space; /* number of free slots in buffer */ + /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/ + + + VALID(EINVAL, rb); + VALID(EINVAL, rb->buffer); + +#if ENABLE_THREADS + if ((rb->flags & O_NONBLOCK) == 0) + { + pthread_mutex_lock(&rb->lock); + } +#endif + + space = rb_space_ns(rb); + +#if ENABLE_THREADS + if ((rb->flags & O_NONBLOCK) == 0) + { + pthread_mutex_unlock(&rb->lock); + } +#endif + + return (long)space; } |