Coverage Report

Created: 2026-01-25 07:18

next uncovered line (L), next uncovered region (R), next uncovered branch (B)
/src/ffmpeg/libavutil/refstruct.h
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/*
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#ifndef AVUTIL_REFSTRUCT_H
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#define AVUTIL_REFSTRUCT_H
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#include <stddef.h>
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/**
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 * RefStruct is an API for creating reference-counted objects
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 * with minimal overhead. The API is designed for objects,
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 * not buffers like the AVBuffer API. The main differences
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 * to the AVBuffer API are as follows:
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 *
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 * - It uses void* instead of uint8_t* as its base type due to
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 *   its focus on objects.
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 * - There are no equivalents of AVBuffer and AVBufferRef.
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 *   E.g. there is no way to get the usable size of the object:
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 *   The user is supposed to know what is at the other end of
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 *   the pointer. It also avoids one level of indirection.
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 * - Custom allocators are not supported. This allows to simplify
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 *   the implementation and reduce the amount of allocations.
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 * - It also has the advantage that the user's free callback need
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 *   only free the resources owned by the object, but not the
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 *   object itself.
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 * - Because referencing (and replacing) an object managed by the
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 *   RefStruct API does not involve allocations, they can not fail
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 *   and therefore need not be checked.
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 *
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 * @note Referencing and unreferencing the buffers is thread-safe and thus
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 * may be done from multiple threads simultaneously without any need for
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 * additional locking.
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 */
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/**
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 * This union is used for all opaque parameters in this API to spare the user
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 * to cast const away in case the opaque to use is const-qualified.
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 *
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 * The functions provided by this API with an AVRefStructOpaque come in pairs
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 * named foo_c and foo. The foo function accepts void* as opaque and is just
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 * a wrapper around the foo_c function; "_c" means "(potentially) const".
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 */
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typedef union {
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    void *nc;
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    const void *c;
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} AVRefStructOpaque;
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/**
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 * If this flag is set in av_refstruct_alloc_ext_c(), the object will not
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 * be initially zeroed.
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 */
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0
#define AV_REFSTRUCT_FLAG_NO_ZEROING (1 << 0)
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/**
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 * Allocate a refcounted object of usable size `size` managed via
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 * the RefStruct API.
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 *
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 * By default (in the absence of flags to the contrary),
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 * the returned object is initially zeroed.
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 *
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 * @param size    Desired usable size of the returned object.
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 * @param flags   A bitwise combination of AV_REFSTRUCT_FLAG_* flags.
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 * @param opaque  A pointer that will be passed to the free_cb callback.
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 * @param free_cb A callback for freeing this object's content
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 *                when its reference count reaches zero;
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 *                it must not free the object itself.
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 * @return A pointer to an object of the desired size or NULL on failure.
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 */
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void *av_refstruct_alloc_ext_c(size_t size, unsigned flags, AVRefStructOpaque opaque,
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                               void (*free_cb)(AVRefStructOpaque opaque, void *obj));
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/**
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 * A wrapper around av_refstruct_alloc_ext_c() for the common case
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 * of a non-const qualified opaque.
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 *
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 * @see av_refstruct_alloc_ext_c()
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 */
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static inline
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void *av_refstruct_alloc_ext(size_t size, unsigned flags, void *opaque,
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                             void (*free_cb)(AVRefStructOpaque opaque, void *obj))
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0
{
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    return av_refstruct_alloc_ext_c(size, flags, (AVRefStructOpaque){.nc = opaque},
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                                    free_cb);
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0
}
Unexecuted instantiation: format.c:av_refstruct_alloc_ext
Unexecuted instantiation: ops.c:av_refstruct_alloc_ext
Unexecuted instantiation: avcodec.c:av_refstruct_alloc_ext
Unexecuted instantiation: decode.c:av_refstruct_alloc_ext
Unexecuted instantiation: get_buffer.c:av_refstruct_alloc_ext
Unexecuted instantiation: pthread_frame.c:av_refstruct_alloc_ext
Unexecuted instantiation: utils.c:av_refstruct_alloc_ext
Unexecuted instantiation: container_fifo.c:av_refstruct_alloc_ext
Unexecuted instantiation: frame.c:av_refstruct_alloc_ext
Unexecuted instantiation: refstruct.c:av_refstruct_alloc_ext
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/**
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 * Equivalent to av_refstruct_alloc_ext(size, 0, NULL, NULL)
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 */
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static inline
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void *av_refstruct_allocz(size_t size)
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0
{
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    return av_refstruct_alloc_ext(size, 0, NULL, NULL);
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0
}
Unexecuted instantiation: format.c:av_refstruct_allocz
Unexecuted instantiation: ops.c:av_refstruct_allocz
Unexecuted instantiation: avcodec.c:av_refstruct_allocz
Unexecuted instantiation: decode.c:av_refstruct_allocz
Unexecuted instantiation: get_buffer.c:av_refstruct_allocz
Unexecuted instantiation: pthread_frame.c:av_refstruct_allocz
Unexecuted instantiation: utils.c:av_refstruct_allocz
Unexecuted instantiation: container_fifo.c:av_refstruct_allocz
Unexecuted instantiation: frame.c:av_refstruct_allocz
Unexecuted instantiation: refstruct.c:av_refstruct_allocz
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/**
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 * Decrement the reference count of the underlying object and automatically
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 * free the object if there are no more references to it.
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 *
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 * `*objp == NULL` is legal and a no-op.
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 *
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 * @param objp Pointer to a pointer that is either NULL or points to an object
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 *             managed via this API. `*objp` is set to NULL on return.
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 */
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void av_refstruct_unref(void *objp);
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/**
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 * Create a new reference to an object managed via this API,
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 * i.e. increment the reference count of the underlying object
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 * and return obj.
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 * @return a pointer equal to obj.
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 */
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void *av_refstruct_ref(void *obj);
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/**
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 * Analog of av_refstruct_ref(), but for constant objects.
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 * @see av_refstruct_ref()
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 */
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const void *av_refstruct_ref_c(const void *obj);
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/**
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 * Ensure `*dstp` refers to the same object as src.
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 *
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 * If `*dstp` is already equal to src, do nothing. Otherwise unreference `*dstp`
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 * and replace it with a new reference to src in case `src != NULL` (this
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 * involves incrementing the reference count of src's underlying object) or
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 * with NULL otherwise.
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 *
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 * @param dstp Pointer to a pointer that is either NULL or points to an object
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 *             managed via this API.
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 * @param src  A pointer to an object managed via this API or NULL.
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 */
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void av_refstruct_replace(void *dstp, const void *src);
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/**
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 * Check whether the reference count of an object managed
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 * via this API is 1.
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 *
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 * @param obj A pointer to an object managed via this API.
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 * @return 1 if the reference count of obj is 1; 0 otherwise.
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 */
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int av_refstruct_exclusive(const void *obj);
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/**
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 * AVRefStructPool is an API for a thread-safe pool of objects managed
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 * via the RefStruct API.
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 *
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 * Frequently allocating and freeing large or complicated objects may be slow
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 * and wasteful. This API is meant to solve this in cases when the caller
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 * needs a set of interchangeable objects.
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 *
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 * At the beginning, the user must call allocate the pool via
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 * av_refstruct_pool_alloc() or its analogue av_refstruct_pool_alloc_ext().
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 * Then whenever an object is needed, call av_refstruct_pool_get() to
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 * get a new or reused object from the pool. This new object works in all
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 * aspects the same way as the ones created by av_refstruct_alloc_ext().
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 * However, when the last reference to this object is unreferenced, it is
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 * (optionally) reset and returned to the pool instead of being freed and
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 * will be reused for subsequent av_refstruct_pool_get() calls.
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 *
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 * When the caller is done with the pool and no longer needs to create any new
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 * objects, av_refstruct_pool_uninit() must be called to mark the pool as
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 * freeable. Then entries returned to the pool will then be freed.
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 * Once all the entries are freed, the pool will automatically be freed.
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 *
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 * Allocating and releasing objects with this API is thread-safe as long as
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 * the user-supplied callbacks (if provided) are thread-safe.
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 */
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/**
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 * The buffer pool. This structure is opaque and not meant to be accessed
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 * directly. It is allocated with the allocators below and freed with
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 * av_refstruct_pool_uninit().
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 */
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typedef struct AVRefStructPool AVRefStructPool;
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/**
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 * If this flag is not set, every object in the pool will be zeroed before
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 * the init callback is called or before it is turned over to the user
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 * for the first time if no init callback has been provided.
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 */
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#define AV_REFSTRUCT_POOL_FLAG_NO_ZEROING         AV_REFSTRUCT_FLAG_NO_ZEROING
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/**
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 * If this flag is set and both init_cb and reset_cb callbacks are provided,
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 * then reset_cb will be called if init_cb fails.
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 * The object passed to reset_cb will be in the state left by init_cb.
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 */
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#define AV_REFSTRUCT_POOL_FLAG_RESET_ON_INIT_ERROR                   (1 << 16)
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/**
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 * If this flag is set and both init_cb and free_entry_cb callbacks are
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 * provided, then free_cb will be called if init_cb fails.
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 *
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 * It will be called after reset_cb in case reset_cb and the
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 * AV_REFSTRUCT_POOL_FLAG_RESET_ON_INIT_ERROR flag are also set.
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 *
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 * The object passed to free_cb will be in the state left by
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 * the callbacks applied earlier (init_cb potentially followed by reset_cb).
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 */
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#define AV_REFSTRUCT_POOL_FLAG_FREE_ON_INIT_ERROR                    (1 << 17)
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/**
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 * If this flag is set, the entries will be zeroed before
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 * being returned to the user (after the init or reset callbacks
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 * have been called (if provided)). Furthermore, to avoid zeroing twice
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 * it also makes the pool behave as if the AV_REFSTRUCT_POOL_FLAG_NO_ZEROING
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 * flag had been provided.
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 */
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#define AV_REFSTRUCT_POOL_FLAG_ZERO_EVERY_TIME                       (1 << 18)
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/**
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 * Equivalent to av_refstruct_pool_alloc(size, flags, NULL, NULL, NULL, NULL, NULL)
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 */
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AVRefStructPool *av_refstruct_pool_alloc(size_t size, unsigned flags);
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/**
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 * Allocate an AVRefStructPool, potentially using complex callbacks.
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 *
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 * @param size size of the entries of the pool
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 * @param flags a bitwise combination of AV_REFSTRUCT_POOL_FLAG_* flags
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 * @param opaque A pointer that will be passed to the callbacks below.
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 * @param init  A callback that will be called directly after a new entry
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 *              has been allocated. obj has already been zeroed unless
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 *              the AV_REFSTRUCT_POOL_FLAG_NO_ZEROING flag is in use.
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 * @param reset A callback that will be called after an entry has been
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 *              returned to the pool and before it is reused.
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 * @param free_entry A callback that will be called when an entry is freed
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 *                   after the pool has been marked as to be uninitialized.
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 * @param free       A callback that will be called when the pool itself is
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 *                   freed (after the last entry has been returned and freed).
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 */
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AVRefStructPool *av_refstruct_pool_alloc_ext_c(size_t size, unsigned flags,
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                                               AVRefStructOpaque opaque,
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                                               int  (*init_cb)(AVRefStructOpaque opaque, void *obj),
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                                               void (*reset_cb)(AVRefStructOpaque opaque, void *obj),
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                                               void (*free_entry_cb)(AVRefStructOpaque opaque, void *obj),
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                                               void (*free_cb)(AVRefStructOpaque opaque));
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/**
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 * A wrapper around av_refstruct_pool_alloc_ext_c() for the common case
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 * of a non-const qualified opaque.
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 *
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 * @see av_refstruct_pool_alloc_ext_c()
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 */
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static inline
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AVRefStructPool *av_refstruct_pool_alloc_ext(size_t size, unsigned flags,
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                                             void *opaque,
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                                             int  (*init_cb)(AVRefStructOpaque opaque, void *obj),
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                                             void (*reset_cb)(AVRefStructOpaque opaque, void *obj),
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                                             void (*free_entry_cb)(AVRefStructOpaque opaque, void *obj),
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                                             void (*free_cb)(AVRefStructOpaque opaque))
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{
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    return av_refstruct_pool_alloc_ext_c(size, flags, (AVRefStructOpaque){.nc = opaque},
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                                         init_cb, reset_cb, free_entry_cb, free_cb);
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0
}
Unexecuted instantiation: format.c:av_refstruct_pool_alloc_ext
Unexecuted instantiation: ops.c:av_refstruct_pool_alloc_ext
Unexecuted instantiation: avcodec.c:av_refstruct_pool_alloc_ext
Unexecuted instantiation: decode.c:av_refstruct_pool_alloc_ext
Unexecuted instantiation: get_buffer.c:av_refstruct_pool_alloc_ext
Unexecuted instantiation: pthread_frame.c:av_refstruct_pool_alloc_ext
Unexecuted instantiation: utils.c:av_refstruct_pool_alloc_ext
Unexecuted instantiation: container_fifo.c:av_refstruct_pool_alloc_ext
Unexecuted instantiation: frame.c:av_refstruct_pool_alloc_ext
Unexecuted instantiation: refstruct.c:av_refstruct_pool_alloc_ext
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/**
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 * Get an object from the pool, reusing an old one from the pool when
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 * available.
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 *
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 * Every call to this function must happen before av_refstruct_pool_uninit().
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 * Otherwise undefined behaviour may occur.
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 *
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 * @param pool the pool from which to get the object
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 * @return a reference to the object on success, NULL on error.
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 */
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void *av_refstruct_pool_get(AVRefStructPool *pool);
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/**
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 * Mark the pool as being available for freeing. It will actually be freed
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 * only once all the allocated buffers associated with the pool are released.
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 * Thus it is safe to call this function while some of the allocated buffers
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 * are still in use.
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 *
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 * It is illegal to try to get a new entry after this function has been called.
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 *
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 * @param poolp pointer to a pointer to either NULL or a pool to be freed.
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 *              `*poolp` will be set to NULL.
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 */
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static inline void av_refstruct_pool_uninit(AVRefStructPool **poolp)
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{
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    av_refstruct_unref(poolp);
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0
}
Unexecuted instantiation: format.c:av_refstruct_pool_uninit
Unexecuted instantiation: ops.c:av_refstruct_pool_uninit
Unexecuted instantiation: avcodec.c:av_refstruct_pool_uninit
Unexecuted instantiation: decode.c:av_refstruct_pool_uninit
Unexecuted instantiation: get_buffer.c:av_refstruct_pool_uninit
Unexecuted instantiation: pthread_frame.c:av_refstruct_pool_uninit
Unexecuted instantiation: utils.c:av_refstruct_pool_uninit
Unexecuted instantiation: container_fifo.c:av_refstruct_pool_uninit
Unexecuted instantiation: frame.c:av_refstruct_pool_uninit
Unexecuted instantiation: refstruct.c:av_refstruct_pool_uninit
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#endif /* AVUTIL_REFSTRUCT_H */