| Message ID | tencent_37A270BD2D7A9A3740B49AD19F34AB934E08@qq.com |
|---|---|
| State | Accepted |
| Commit | 5d8d3c1ac211c3b13a2dcce5214dcf250c6c61f2 |
| Headers | show |
| Series | [FFmpeg-devel] avutil/mem: fix doc for reallocs | expand |
| Context | Check | Description |
|---|---|---|
| yinshiyou/make_loongarch64 | success | Make finished |
| yinshiyou/make_fate_loongarch64 | success | Make fate finished |
| andriy/make_x86 | success | Make finished |
| andriy/make_fate_x86 | success | Make fate finished |
Ping. > On Apr 2, 2022, at 1:05 AM, Zhao Zhili <quinkblack@foxmail.com> wrote: > > The doc says those function are like av_free if size or nmemb is > zero. It doesn't match the code. av_realloc() realloc one byte if > size is zero, which was added by 91ff05f6ac5 ten years ago. > realloc() itself in C is implementation-dependent. Make the doc > match the longstanding behaviour. > --- > libavutil/mem.h | 23 +++++++++++------------ > 1 file changed, 11 insertions(+), 12 deletions(-) > > diff --git a/libavutil/mem.h b/libavutil/mem.h > index b9fe80738c..d91174196c 100644 > --- a/libavutil/mem.h > +++ b/libavutil/mem.h > @@ -250,8 +250,7 @@ void *av_mallocz_array(size_t nmemb, size_t size) av_malloc_attrib av_alloc_size > /** > * Allocate, reallocate, or free a block of memory. > * > - * If `ptr` is `NULL` and `size` > 0, allocate a new block. If `size` is > - * zero, free the memory block pointed to by `ptr`. Otherwise, expand or > + * If `ptr` is `NULL` and `size` > 0, allocate a new block. Otherwise, expand or > * shrink that block of memory according to `size`. > * > * @param ptr Pointer to a memory block already allocated with > @@ -260,10 +259,11 @@ void *av_mallocz_array(size_t nmemb, size_t size) av_malloc_attrib av_alloc_size > * reallocated > * > * @return Pointer to a newly-reallocated block or `NULL` if the block > - * cannot be reallocated or the function is used to free the memory block > + * cannot be reallocated > * > * @warning Unlike av_malloc(), the returned pointer is not guaranteed to be > - * correctly aligned. > + * correctly aligned. The returned pointer must be freed after even > + * if size is zero. > * @see av_fast_realloc() > * @see av_reallocp() > */ > @@ -311,8 +311,7 @@ void *av_realloc_f(void *ptr, size_t nelem, size_t elsize); > /** > * Allocate, reallocate, or free an array. > * > - * If `ptr` is `NULL` and `nmemb` > 0, allocate a new block. If > - * `nmemb` is zero, free the memory block pointed to by `ptr`. > + * If `ptr` is `NULL` and `nmemb` > 0, allocate a new block. > * > * @param ptr Pointer to a memory block already allocated with > * av_realloc() or `NULL` > @@ -320,19 +319,19 @@ void *av_realloc_f(void *ptr, size_t nelem, size_t elsize); > * @param size Size of the single element of the array > * > * @return Pointer to a newly-reallocated block or NULL if the block > - * cannot be reallocated or the function is used to free the memory block > + * cannot be reallocated > * > * @warning Unlike av_malloc(), the allocated memory is not guaranteed to be > - * correctly aligned. > + * correctly aligned. The returned pointer must be freed after even if > + * nmemb is zero. > * @see av_reallocp_array() > */ > av_alloc_size(2, 3) void *av_realloc_array(void *ptr, size_t nmemb, size_t size); > > /** > - * Allocate, reallocate, or free an array through a pointer to a pointer. > + * Allocate, reallocate an array through a pointer to a pointer. > * > - * If `*ptr` is `NULL` and `nmemb` > 0, allocate a new block. If `nmemb` is > - * zero, free the memory block pointed to by `*ptr`. > + * If `*ptr` is `NULL` and `nmemb` > 0, allocate a new block. > * > * @param[in,out] ptr Pointer to a pointer to a memory block already > * allocated with av_realloc(), or a pointer to `NULL`. > @@ -343,7 +342,7 @@ av_alloc_size(2, 3) void *av_realloc_array(void *ptr, size_t nmemb, size_t size) > * @return Zero on success, an AVERROR error code on failure > * > * @warning Unlike av_malloc(), the allocated memory is not guaranteed to be > - * correctly aligned. > + * correctly aligned. *ptr must be freed after even if nmemb is zero. > */ > int av_reallocp_array(void *ptr, size_t nmemb, size_t size); > > -- > 2.31.1 >
On Sat, Apr 02, 2022 at 01:05:37AM +0800, Zhao Zhili wrote: > The doc says those function are like av_free if size or nmemb is > zero. It doesn't match the code. av_realloc() realloc one byte if > size is zero, which was added by 91ff05f6ac5 ten years ago. > realloc() itself in C is implementation-dependent. Make the doc > match the longstanding behaviour. > --- > libavutil/mem.h | 23 +++++++++++------------ > 1 file changed, 11 insertions(+), 12 deletions(-) patch probably ok thx [...]
diff --git a/libavutil/mem.h b/libavutil/mem.h index b9fe80738c..d91174196c 100644 --- a/libavutil/mem.h +++ b/libavutil/mem.h @@ -250,8 +250,7 @@ void *av_mallocz_array(size_t nmemb, size_t size) av_malloc_attrib av_alloc_size /** * Allocate, reallocate, or free a block of memory. * - * If `ptr` is `NULL` and `size` > 0, allocate a new block. If `size` is - * zero, free the memory block pointed to by `ptr`. Otherwise, expand or + * If `ptr` is `NULL` and `size` > 0, allocate a new block. Otherwise, expand or * shrink that block of memory according to `size`. * * @param ptr Pointer to a memory block already allocated with @@ -260,10 +259,11 @@ void *av_mallocz_array(size_t nmemb, size_t size) av_malloc_attrib av_alloc_size * reallocated * * @return Pointer to a newly-reallocated block or `NULL` if the block - * cannot be reallocated or the function is used to free the memory block + * cannot be reallocated * * @warning Unlike av_malloc(), the returned pointer is not guaranteed to be - * correctly aligned. + * correctly aligned. The returned pointer must be freed after even + * if size is zero. * @see av_fast_realloc() * @see av_reallocp() */ @@ -311,8 +311,7 @@ void *av_realloc_f(void *ptr, size_t nelem, size_t elsize); /** * Allocate, reallocate, or free an array. * - * If `ptr` is `NULL` and `nmemb` > 0, allocate a new block. If - * `nmemb` is zero, free the memory block pointed to by `ptr`. + * If `ptr` is `NULL` and `nmemb` > 0, allocate a new block. * * @param ptr Pointer to a memory block already allocated with * av_realloc() or `NULL` @@ -320,19 +319,19 @@ void *av_realloc_f(void *ptr, size_t nelem, size_t elsize); * @param size Size of the single element of the array * * @return Pointer to a newly-reallocated block or NULL if the block - * cannot be reallocated or the function is used to free the memory block + * cannot be reallocated * * @warning Unlike av_malloc(), the allocated memory is not guaranteed to be - * correctly aligned. + * correctly aligned. The returned pointer must be freed after even if + * nmemb is zero. * @see av_reallocp_array() */ av_alloc_size(2, 3) void *av_realloc_array(void *ptr, size_t nmemb, size_t size); /** - * Allocate, reallocate, or free an array through a pointer to a pointer. + * Allocate, reallocate an array through a pointer to a pointer. * - * If `*ptr` is `NULL` and `nmemb` > 0, allocate a new block. If `nmemb` is - * zero, free the memory block pointed to by `*ptr`. + * If `*ptr` is `NULL` and `nmemb` > 0, allocate a new block. * * @param[in,out] ptr Pointer to a pointer to a memory block already * allocated with av_realloc(), or a pointer to `NULL`. @@ -343,7 +342,7 @@ av_alloc_size(2, 3) void *av_realloc_array(void *ptr, size_t nmemb, size_t size) * @return Zero on success, an AVERROR error code on failure * * @warning Unlike av_malloc(), the allocated memory is not guaranteed to be - * correctly aligned. + * correctly aligned. *ptr must be freed after even if nmemb is zero. */ int av_reallocp_array(void *ptr, size_t nmemb, size_t size);