1 3b0f3d61 2020-01-22 neels /* Auto-reallocating array for arbitrary member types. */
 2 3b0f3d61 2020-01-22 neels /*
 3 3b0f3d61 2020-01-22 neels  * Copyright (c) 2020 Neels Hofmeyr <neels@hofmeyr.de>
 4 3b0f3d61 2020-01-22 neels  *
 5 3b0f3d61 2020-01-22 neels  * Permission to use, copy, modify, and distribute this software for any
 6 3b0f3d61 2020-01-22 neels  * purpose with or without fee is hereby granted, provided that the above
 7 3b0f3d61 2020-01-22 neels  * copyright notice and this permission notice appear in all copies.
 8 3b0f3d61 2020-01-22 neels  *
 9 3b0f3d61 2020-01-22 neels  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 3b0f3d61 2020-01-22 neels  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 3b0f3d61 2020-01-22 neels  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 3b0f3d61 2020-01-22 neels  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 3b0f3d61 2020-01-22 neels  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 3b0f3d61 2020-01-22 neels  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 3b0f3d61 2020-01-22 neels  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 3b0f3d61 2020-01-22 neels  */
17 3b0f3d61 2020-01-22 neels 
18 3b0f3d61 2020-01-22 neels #pragma once
19 3b0f3d61 2020-01-22 neels 
20 3b0f3d61 2020-01-22 neels #ifdef __linux__
21 3b0f3d61 2020-01-22 neels /* stupid shims to compile and test on linux */
22 3b0f3d61 2020-01-22 neels #include <strings.h>
23 3b0f3d61 2020-01-22 neels static inline void *reallocarray(void *buf, size_t n, size_t member_size)
24 3b0f3d61 2020-01-22 neels {
25 3b0f3d61 2020-01-22 neels 	return realloc(buf, n * member_size);
26 3b0f3d61 2020-01-22 neels }
27 3b0f3d61 2020-01-22 neels static inline void *recallocarray(void *buf, size_t oldn, size_t n, size_t member_size)
28 3b0f3d61 2020-01-22 neels {
29 3b0f3d61 2020-01-22 neels 	buf = reallocarray(buf, n, member_size);
30 3b0f3d61 2020-01-22 neels 	bzero(((char*)buf) + (oldn * member_size), (n - oldn) * member_size);
31 3b0f3d61 2020-01-22 neels 	return buf;
32 3b0f3d61 2020-01-22 neels }
33 3b0f3d61 2020-01-22 neels #endif
34 3b0f3d61 2020-01-22 neels 
35 3b0f3d61 2020-01-22 neels 
36 3b0f3d61 2020-01-22 neels /* Usage:
37 3b0f3d61 2020-01-22 neels  *
38 3b0f3d61 2020-01-22 neels  * ARRAYLIST(any_type_t) list;
39 3b0f3d61 2020-01-22 neels  * // OR
40 3b0f3d61 2020-01-22 neels  * typedef ARRAYLIST(any_type_t) any_type_list_t;
41 3b0f3d61 2020-01-22 neels  * any_type_list_t list;
42 3b0f3d61 2020-01-22 neels  *
43 3b0f3d61 2020-01-22 neels  * ARRAYLIST_INIT(list, 128); // < number of (at first unused) members to add on each realloc
44 3b0f3d61 2020-01-22 neels  * any_type_t *x;
45 3b0f3d61 2020-01-22 neels  * while (bar) {
46 3b0f3d61 2020-01-22 neels  *         ARRAYLIST_ADD(x, list); // < enlarges the allocated array as needed; list.head may change due to realloc
47 3b0f3d61 2020-01-22 neels  *         if (!x)
48 3b0f3d61 2020-01-22 neels  *                 abort();
49 3b0f3d61 2020-01-22 neels  *         *x = random_foo_value;
50 3b0f3d61 2020-01-22 neels  * }
51 3b0f3d61 2020-01-22 neels  * for (i = 0; i < list.len; i++)
52 3b0f3d61 2020-01-22 neels  *         printf("%s", foo_to_str(list.head[i]));
53 3b0f3d61 2020-01-22 neels  * ARRAYLIST_FREE(list);
54 3b0f3d61 2020-01-22 neels  */
55 3b0f3d61 2020-01-22 neels #define ARRAYLIST(MEMBER_TYPE) \
56 3b0f3d61 2020-01-22 neels 	struct { \
57 3b0f3d61 2020-01-22 neels 		MEMBER_TYPE *head; \
58 3b0f3d61 2020-01-22 neels 		unsigned int len; \
59 3b0f3d61 2020-01-22 neels 		unsigned int allocated; \
60 3b0f3d61 2020-01-22 neels 		unsigned int alloc_blocksize; \
61 3b0f3d61 2020-01-22 neels 	}
62 3b0f3d61 2020-01-22 neels 
63 3b0f3d61 2020-01-22 neels #define ARRAYLIST_INIT(ARRAY_LIST, ALLOC_BLOCKSIZE) do { \
64 3b0f3d61 2020-01-22 neels 		(ARRAY_LIST).head = NULL; \
65 3b0f3d61 2020-01-22 neels 		(ARRAY_LIST).len = 0; \
66 3b0f3d61 2020-01-22 neels 		(ARRAY_LIST).allocated = 0; \
67 3b0f3d61 2020-01-22 neels 		(ARRAY_LIST).alloc_blocksize = ALLOC_BLOCKSIZE; \
68 3b0f3d61 2020-01-22 neels 	} while(0)
69 3b0f3d61 2020-01-22 neels 
70 3b0f3d61 2020-01-22 neels #define ARRAYLIST_ADD(NEW_ITEM_P, ARRAY_LIST) do { \
71 3b0f3d61 2020-01-22 neels 		if ((ARRAY_LIST).len && !(ARRAY_LIST).allocated) { \
72 3b0f3d61 2020-01-22 neels 			NEW_ITEM_P = NULL; \
73 3b0f3d61 2020-01-22 neels 			break; \
74 3b0f3d61 2020-01-22 neels 		} \
75 3b0f3d61 2020-01-22 neels 		if ((ARRAY_LIST).head == NULL || (ARRAY_LIST).allocated < (ARRAY_LIST).len + 1) { \
76 3b0f3d61 2020-01-22 neels 			(ARRAY_LIST).allocated += (ARRAY_LIST).alloc_blocksize ? : 8; \
77 3b0f3d61 2020-01-22 neels 			(ARRAY_LIST).head = recallocarray((ARRAY_LIST).head, (ARRAY_LIST).len, \
78 3b0f3d61 2020-01-22 neels 							  (ARRAY_LIST).allocated, sizeof(*(ARRAY_LIST).head)); \
79 3b0f3d61 2020-01-22 neels 		}; \
80 3b0f3d61 2020-01-22 neels 		if (!(ARRAY_LIST).head || (ARRAY_LIST).allocated < (ARRAY_LIST).len + 1) { \
81 3b0f3d61 2020-01-22 neels 			NEW_ITEM_P = NULL; \
82 3b0f3d61 2020-01-22 neels 			break; \
83 3b0f3d61 2020-01-22 neels 		} \
84 3b0f3d61 2020-01-22 neels 		(NEW_ITEM_P) = &(ARRAY_LIST).head[(ARRAY_LIST).len]; \
85 3b0f3d61 2020-01-22 neels 		(ARRAY_LIST).len++; \
86 3b0f3d61 2020-01-22 neels 	} while (0)
87 3b0f3d61 2020-01-22 neels 
88 3b0f3d61 2020-01-22 neels #define ARRAYLIST_CLEAR(ARRAY_LIST) \
89 3b0f3d61 2020-01-22 neels 	(ARRAY_LIST).len = 0
90 3b0f3d61 2020-01-22 neels 
91 3b0f3d61 2020-01-22 neels #define ARRAYLIST_FREE(ARRAY_LIST) \
92 3b0f3d61 2020-01-22 neels 	do { \
93 3b0f3d61 2020-01-22 neels 		if ((ARRAY_LIST).head && (ARRAY_LIST).allocated) \
94 3b0f3d61 2020-01-22 neels 			free((ARRAY_LIST).head); \
95 3b0f3d61 2020-01-22 neels 		ARRAYLIST_INIT(ARRAY_LIST, (ARRAY_LIST).alloc_blocksize); \
96 3b0f3d61 2020-01-22 neels 	} while(0)