jp9000/obs-studio
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

libobs/util: Add funcs to push zeroed data to circlebufs

Browse Source 
Adds circlebuf_push_front_zero and circlebuf_push_back_zero to
conveniently push zeroed data to the front/back of the buffer without
having to create an intermediary buffer to accomplish the same thing.
This commit is contained in:
jp9000 2017-12-02 13:51:21 -08:00
parent 895814aa8e
commit 5d9854ea44
2 changed files with 60 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
docs/sphinx/reference-libobs-util-circlebuf.rst
View File

@ -91,6 +91,24 @@ Circular Buffer Inline Functions
---------------------
.. function:: void circlebuf_push_back_zero(struct circlebuf *cb, size_t size)
Pushes zeroed data to the end of the circular buffer.
:param cb: The circular buffer
:param size: Size
---------------------
.. function:: void circlebuf_push_front_zero(struct circlebuf *cb, size_t size)
Pushes zeroed data to the front of the circular buffer.
:param cb: The circular buffer
:param size: Size
---------------------
.. function:: void circlebuf_peek_front(struct circlebuf *cb, void *data, size_t size)
Peeks data at the front of the circular buffer.

42
libobs/util/circlebuf.h
View File

@ -189,6 +189,48 @@ static inline void circlebuf_push_front(struct circlebuf *cb, const void *data,
}
}
static inline void circlebuf_push_back_zero(struct circlebuf *cb, size_t size)
{
size_t new_end_pos = cb->end_pos + size;
cb->size += size;
circlebuf_ensure_capacity(cb);
if (new_end_pos > cb->capacity) {
size_t back_size = cb->capacity - cb->end_pos;
size_t loop_size = size - back_size;
if (back_size)
memset((uint8_t*)cb->data + cb->end_pos, 0, back_size);
memset(cb->data, 0, loop_size);
new_end_pos -= cb->capacity;
} else {
memset((uint8_t*)cb->data + cb->end_pos, 0, size);
}
cb->end_pos = new_end_pos;
}
static inline void circlebuf_push_front_zero(struct circlebuf *cb, size_t size)
{
cb->size += size;
circlebuf_ensure_capacity(cb);
if (cb->start_pos < size) {
size_t back_size = size - cb->start_pos;
if (cb->start_pos)
memset(cb->data, 0, cb->start_pos);
cb->start_pos = cb->capacity - back_size;
memset((uint8_t*)cb->data + cb->start_pos, 0, back_size);
} else {
cb->start_pos -= size;
memset((uint8_t*)cb->data + cb->start_pos, 0, size);
}
}
static inline void circlebuf_peek_front(struct circlebuf *cb, void *data,
size_t size)
{