xref: /linux/sound/hda/array.c (revision bd628c1bed7902ec1f24ba0fe70758949146abbe)
1 /*
2  * generic arrays
3  */
4 
5 #include <linux/slab.h>
6 #include <sound/core.h>
7 #include <sound/hdaudio.h>
8 
9 /**
10  * snd_array_new - get a new element from the given array
11  * @array: the array object
12  *
13  * Get a new element from the given array.  If it exceeds the
14  * pre-allocated array size, re-allocate the array.
15  *
16  * Returns NULL if allocation failed.
17  */
18 void *snd_array_new(struct snd_array *array)
19 {
20 	if (snd_BUG_ON(!array->elem_size))
21 		return NULL;
22 	if (array->used >= array->alloced) {
23 		int num = array->alloced + array->alloc_align;
24 		int oldsize = array->alloced * array->elem_size;
25 		int size = (num + 1) * array->elem_size;
26 		void *nlist;
27 		if (snd_BUG_ON(num >= 4096))
28 			return NULL;
29 		nlist = krealloc(array->list, size, GFP_KERNEL);
30 		if (!nlist)
31 			return NULL;
32 		memset(nlist + oldsize, 0, size - oldsize);
33 		array->list = nlist;
34 		array->alloced = num;
35 	}
36 	return snd_array_elem(array, array->used++);
37 }
38 EXPORT_SYMBOL_GPL(snd_array_new);
39 
40 /**
41  * snd_array_free - free the given array elements
42  * @array: the array object
43  */
44 void snd_array_free(struct snd_array *array)
45 {
46 	kfree(array->list);
47 	array->used = 0;
48 	array->alloced = 0;
49 	array->list = NULL;
50 }
51 EXPORT_SYMBOL_GPL(snd_array_free);
52