1 /*
2 * Copyright © 2015 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 */
23
24 /*
25 * u_vector is a vector based queue for storing arbitrary
26 * sized arrays of objects without using a linked list.
27 */
28
29 #ifndef U_VECTOR_H
30 #define U_VECTOR_H
31
32 #include <stdint.h>
33 #include <stdlib.h>
34 #include "util/macros.h"
35 #include "util/u_math.h"
36
37 #ifdef __cplusplus
38 extern "C" {
39 #endif
40
41 struct u_vector {
42 uint32_t head;
43 uint32_t tail;
44 uint32_t element_size;
45 uint32_t size;
46 void *data;
47 };
48
49 int u_vector_init_pow2(struct u_vector *queue,
50 uint32_t initial_element_count,
51 uint32_t element_size);
52
53 void *u_vector_add(struct u_vector *queue);
54 void *u_vector_remove(struct u_vector *queue);
55
56 static inline int
u_vector_init(struct u_vector * queue,uint32_t initial_element_count,uint32_t element_size)57 u_vector_init(struct u_vector *queue,
58 uint32_t initial_element_count,
59 uint32_t element_size)
60 {
61 initial_element_count = util_next_power_of_two(initial_element_count);
62 element_size = util_next_power_of_two(element_size);
63 return u_vector_init_pow2(queue, initial_element_count, element_size);
64 }
65
66 static inline int
u_vector_length(struct u_vector * queue)67 u_vector_length(struct u_vector *queue)
68 {
69 return (queue->head - queue->tail) / queue->element_size;
70 }
71
72 static inline void *
u_vector_head(struct u_vector * vector)73 u_vector_head(struct u_vector *vector)
74 {
75 assert(vector->tail < vector->head);
76 return (void *)((char *)vector->data +
77 ((vector->head - vector->element_size) &
78 (vector->size - 1)));
79 }
80
81 static inline void *
u_vector_tail(struct u_vector * vector)82 u_vector_tail(struct u_vector *vector)
83 {
84 return (void *)((char *)vector->data + (vector->tail & (vector->size - 1)));
85 }
86
87 static inline void
u_vector_finish(struct u_vector * queue)88 u_vector_finish(struct u_vector *queue)
89 {
90 free(queue->data);
91 }
92
93 #ifdef __cplusplus
94 #define u_vector_element_cast(elem) (decltype(elem))
95 #else
96 #define u_vector_element_cast(elem) (void *)
97 #endif
98
99 #define u_vector_foreach(elem, queue) \
100 STATIC_ASSERT(__builtin_types_compatible_p(__typeof__(queue), struct u_vector *)); \
101 for (uint32_t __u_vector_offset = (queue)->tail; \
102 elem = u_vector_element_cast(elem)((char *)(queue)->data + \
103 (__u_vector_offset & ((queue)->size - 1))), \
104 __u_vector_offset != (queue)->head; \
105 __u_vector_offset += (queue)->element_size)
106
107 #ifdef __cplusplus
108 }
109 #endif
110
111 #endif
112
113