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Diffstat (limited to 'Alc/ringbuffer.h')
-rw-r--r-- | Alc/ringbuffer.h | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/Alc/ringbuffer.h b/Alc/ringbuffer.h new file mode 100644 index 00000000..0d05ec84 --- /dev/null +++ b/Alc/ringbuffer.h @@ -0,0 +1,77 @@ +#ifndef RINGBUFFER_H +#define RINGBUFFER_H + +#include <stddef.h> + + +#ifdef __cplusplus +extern "C" { +#endif + +typedef struct ll_ringbuffer ll_ringbuffer_t; +typedef struct ll_ringbuffer_data { + char *buf; + size_t len; +} ll_ringbuffer_data_t; + + +/** + * Create a new ringbuffer to hold at least `sz' elements of `elem_sz' bytes. + * The number of elements is rounded up to the next power of two (even if it is + * already a power of two, to ensure the requested amount can be written). + */ +ll_ringbuffer_t *ll_ringbuffer_create(size_t sz, size_t elem_sz, int limit_writes); +/** Free all data associated with the ringbuffer `rb'. */ +void ll_ringbuffer_free(ll_ringbuffer_t *rb); +/** Reset the read and write pointers to zero. This is not thread safe. */ +void ll_ringbuffer_reset(ll_ringbuffer_t *rb); + +/** + * The non-copying data reader. `vec' is an array of two places. Set the values + * at `vec' to hold the current readable data at `rb'. If the readable data is + * in one segment the second segment has zero length. + */ +void ll_ringbuffer_get_read_vector(const ll_ringbuffer_t *rb, ll_ringbuffer_data_t vec[2]); +/** + * The non-copying data writer. `vec' is an array of two places. Set the values + * at `vec' to hold the current writeable data at `rb'. If the writeable data + * is in one segment the second segment has zero length. + */ +void ll_ringbuffer_get_write_vector(const ll_ringbuffer_t *rb, ll_ringbuffer_data_t vec[2]); + +/** + * Return the number of elements available for reading. This is the number of + * elements in front of the read pointer and behind the write pointer. + */ +size_t ll_ringbuffer_read_space(const ll_ringbuffer_t *rb); +/** + * The copying data reader. Copy at most `cnt' elements from `rb' to `dest'. + * Returns the actual number of elements copied. + */ +size_t ll_ringbuffer_read(ll_ringbuffer_t *rb, char *dest, size_t cnt); +/** + * The copying data reader w/o read pointer advance. Copy at most `cnt' + * elements from `rb' to `dest'. Returns the actual number of elements copied. + */ +size_t ll_ringbuffer_peek(ll_ringbuffer_t *rb, char *dest, size_t cnt); +/** Advance the read pointer `cnt' places. */ +void ll_ringbuffer_read_advance(ll_ringbuffer_t *rb, size_t cnt); + +/** + * Return the number of elements available for writing. This is the number of + * elements in front of the write pointer and behind the read pointer. + */ +size_t ll_ringbuffer_write_space(const ll_ringbuffer_t *rb); +/** + * The copying data writer. Copy at most `cnt' elements to `rb' from `src'. + * Returns the actual number of elements copied. + */ +size_t ll_ringbuffer_write(ll_ringbuffer_t *rb, const char *src, size_t cnt); +/** Advance the write pointer `cnt' places. */ +void ll_ringbuffer_write_advance(ll_ringbuffer_t *rb, size_t cnt); + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +#endif /* RINGBUFFER_H */ |