1 /* PipeWire
2 *
3 * Copyright © 2018 Wim Taymans
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice (including the next
13 * paragraph) shall be included in all copies or substantial portions of the
14 * Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22 * DEALINGS IN THE SOFTWARE.
23 */
24
25 #ifndef PIPEWIRE_ARRAY_H
26 #define PIPEWIRE_ARRAY_H
27
28 #ifdef __cplusplus
29 extern "C" {
30 #endif
31
32 #include <errno.h>
33
34 #include <spa/utils/defs.h>
35
36 /** \class pw_array
37 *
38 * \brief An array object
39 *
40 * The array is a dynamically resizable data structure that can
41 * hold items of the same size.
42 */
43 struct pw_array {
44 void *data; /**< pointer to array data */
45 size_t size; /**< length of array in bytes */
46 size_t alloc; /**< number of allocated memory in \a data */
47 size_t extend; /**< number of bytes to extend with */
48 };
49
50 #define PW_ARRAY_INIT(extend) (struct pw_array) { NULL, 0, 0, extend }
51
52 #define pw_array_get_len_s(a,s) ((a)->size / (s))
53 #define pw_array_get_unchecked_s(a,idx,s,t) SPA_MEMBER((a)->data,(idx)*(s),t)
54 #define pw_array_check_index_s(a,idx,s) ((idx) < pw_array_get_len_s(a,s))
55
56 /** Get the number of items of type \a t in array \memberof pw_array */
57 #define pw_array_get_len(a,t) pw_array_get_len_s(a,sizeof(t))
58 /** Get the item with index \a idx and type \a t from array \memberof pw_array */
59 #define pw_array_get_unchecked(a,idx,t) pw_array_get_unchecked_s(a,idx,sizeof(t),t)
60 /** Check if an item with index \a idx and type \a t exist in array \memberof pw_array */
61 #define pw_array_check_index(a,idx,t) pw_array_check_index_s(a,idx,sizeof(t))
62
63 #define pw_array_first(a) ((a)->data)
64 #define pw_array_end(a) SPA_MEMBER((a)->data, (a)->size, void)
65 #define pw_array_check(a,p) (SPA_MEMBER(p,sizeof(*p),void) <= pw_array_end(a))
66
67 #define pw_array_for_each(pos, array) \
68 for (pos = (__typeof__(pos)) pw_array_first(array); \
69 pw_array_check(array, pos); \
70 (pos)++)
71
72 #define pw_array_consume(pos, array) \
73 for (pos = (__typeof__(pos)) pw_array_first(array); \
74 pw_array_check(array, pos); \
75 pos = (__typeof__(pos)) pw_array_first(array))
76
77 #define pw_array_remove(a,p) \
78 ({ \
79 (a)->size -= sizeof(*(p)); \
80 memmove(p, SPA_MEMBER((p), sizeof(*(p)), void), \
81 SPA_PTRDIFF(pw_array_end(a),(p))); \
82 })
83
84 /** Initialize the array with given extend \memberof pw_array */
pw_array_init(struct pw_array * arr,size_t extend)85 static inline void pw_array_init(struct pw_array *arr, size_t extend)
86 {
87 arr->data = NULL;
88 arr->size = arr->alloc = 0;
89 arr->extend = extend;
90 }
91
92 /** Clear the array */
pw_array_clear(struct pw_array * arr)93 static inline void pw_array_clear(struct pw_array *arr)
94 {
95 free(arr->data);
96 }
97
98 /** Reset the array */
pw_array_reset(struct pw_array * arr)99 static inline void pw_array_reset(struct pw_array *arr)
100 {
101 arr->size = 0;
102 }
103
104 /** Make sure \a size bytes can be added to the array \memberof pw_array */
pw_array_ensure_size(struct pw_array * arr,size_t size)105 static inline int pw_array_ensure_size(struct pw_array *arr, size_t size)
106 {
107 size_t alloc, need;
108
109 alloc = arr->alloc;
110 need = arr->size + size;
111
112 if (SPA_UNLIKELY(alloc < need)) {
113 void *data;
114 alloc = SPA_MAX(alloc, arr->extend);
115 while (alloc < need)
116 alloc *= 2;
117 if (SPA_UNLIKELY((data = realloc(arr->data, alloc)) == NULL))
118 return -errno;
119 arr->data = data;
120 arr->alloc = alloc;
121 }
122 return 0;
123 }
124
125 /** Add \a ref size bytes to \a arr. A pointer to memory that can
126 * hold at least \a size bytes is returned \memberof pw_array */
pw_array_add(struct pw_array * arr,size_t size)127 static inline void *pw_array_add(struct pw_array *arr, size_t size)
128 {
129 void *p;
130
131 if (pw_array_ensure_size(arr, size) < 0)
132 return NULL;
133
134 p = SPA_MEMBER(arr->data, arr->size, void);
135 arr->size += size;
136
137 return p;
138 }
139
140 /** Add \a ref size bytes to \a arr. When there is not enough memory to
141 * hold \a size bytes, NULL is returned \memberof pw_array */
pw_array_add_fixed(struct pw_array * arr,size_t size)142 static inline void *pw_array_add_fixed(struct pw_array *arr, size_t size)
143 {
144 void *p;
145
146 if (SPA_UNLIKELY(arr->alloc < arr->size + size)) {
147 errno = ENOSPC;
148 return NULL;
149 }
150
151 p = SPA_MEMBER(arr->data, arr->size, void);
152 arr->size += size;
153
154 return p;
155 }
156
157 /** Add a pointer to array \memberof pw_array */
158 #define pw_array_add_ptr(a,p) \
159 *((void**) pw_array_add(a, sizeof(void*))) = (p)
160
161 #ifdef __cplusplus
162 } /* extern "C" */
163 #endif
164
165 #endif /* PIPEWIRE_ARRAY_H */
166