xref: /linux/sound/hda/array.c (revision da1d9caf95def6f0320819cf941c9fd1069ba9e1)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * generic arrays
4  */
5 
6 #include <linux/slab.h>
7 #include <sound/core.h>
8 #include <sound/hdaudio.h>
9 
10 /**
11  * snd_array_new - get a new element from the given array
12  * @array: the array object
13  *
14  * Get a new element from the given array.  If it exceeds the
15  * pre-allocated array size, re-allocate the array.
16  *
17  * Returns NULL if allocation failed.
18  */
19 void *snd_array_new(struct snd_array *array)
20 {
21 	if (snd_BUG_ON(!array->elem_size))
22 		return NULL;
23 	if (array->used >= array->alloced) {
24 		int num = array->alloced + array->alloc_align;
25 		int oldsize = array->alloced * array->elem_size;
26 		int size = (num + 1) * array->elem_size;
27 		void *nlist;
28 		if (snd_BUG_ON(num >= 4096))
29 			return NULL;
30 		nlist = krealloc(array->list, size, GFP_KERNEL);
31 		if (!nlist)
32 			return NULL;
33 		memset(nlist + oldsize, 0, size - oldsize);
34 		array->list = nlist;
35 		array->alloced = num;
36 	}
37 	return snd_array_elem(array, array->used++);
38 }
39 EXPORT_SYMBOL_GPL(snd_array_new);
40 
41 /**
42  * snd_array_free - free the given array elements
43  * @array: the array object
44  */
45 void snd_array_free(struct snd_array *array)
46 {
47 	kfree(array->list);
48 	array->used = 0;
49 	array->alloced = 0;
50 	array->list = NULL;
51 }
52 EXPORT_SYMBOL_GPL(snd_array_free);
53