src/util/stack_array.h

/*
 * Copyright © 2025 Collabora, Ltd.
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 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
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 * Software.
 *
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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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 */

#include <stdlib.h>

#ifndef UTIL_STACK_ARRAY_H
#define UTIL_STACK_ARRAY_H

#define STACK_ARRAY_SIZE 8

/* Sometimes gcc may claim -Wmaybe-uninitialized for the stack array in some
 * places it can't verify that when size is 0 nobody down the call chain reads
 * the array. Please don't try to fix it by zero-initializing the array here
 * since it's used in a lot of different places. An "if (size == 0) return;"
 * may work for you.
 */
#define STACK_ARRAY(type, name, size) \
   type _stack_##name[STACK_ARRAY_SIZE]; \
   type *const name = \
     ((size) <= STACK_ARRAY_SIZE ? _stack_##name : (type *)malloc((size) * sizeof(type)))

#define STACK_ARRAY_FINISH(name) \
   if (name != _stack_##name) free(name)

#endif /* UTIL_STACK_ARRAY_H */