1/**************************************************************************
2 *
3 * Copyright 2010 Luca Barbieri
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining
6 * a copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sublicense, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
12 *
13 * The above copyright notice and this permission notice (including the
14 * next paragraph) shall be included in all copies or substantial
15 * portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
20 * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 *
25 **************************************************************************/
26
27#ifndef U_DYNARRAY_H
28#define U_DYNARRAY_H
29
30#include "pipe/p_compiler.h"
31#include "util/u_memory.h"
32
33/* A zero-initialized version of this is guaranteed to represent an
34 * empty array.
35 *
36 * Also, size <= capacity and data != 0 if and only if capacity != 0
37 * capacity will always be the allocation size of data
38 */
39struct util_dynarray
40{
41   void *data;
42   unsigned size;
43   unsigned capacity;
44};
45
46static INLINE void
47util_dynarray_init(struct util_dynarray *buf)
48{
49   memset(buf, 0, sizeof(*buf));
50}
51
52static INLINE void
53util_dynarray_fini(struct util_dynarray *buf)
54{
55   if(buf->data)
56   {
57      FREE(buf->data);
58      util_dynarray_init(buf);
59   }
60}
61
62/* use util_dynarray_trim to reduce the allocated storage */
63static INLINE void *
64util_dynarray_resize(struct util_dynarray *buf, unsigned newsize)
65{
66   char *p;
67   if(newsize > buf->capacity)
68   {
69      unsigned newcap = buf->capacity << 1;
70      if(newsize > newcap)
71	      newcap = newsize;
72      buf->data = REALLOC(buf->data, buf->capacity, newcap);
73      buf->capacity = newcap;
74   }
75
76   p = (char *)buf->data + buf->size;
77   buf->size = newsize;
78   return p;
79}
80
81static INLINE void *
82util_dynarray_grow(struct util_dynarray *buf, int diff)
83{
84   return util_dynarray_resize(buf, buf->size + diff);
85}
86
87static INLINE void
88util_dynarray_trim(struct util_dynarray *buf)
89{
90   if (buf->size != buf->capacity) {
91      if (buf->size) {
92         buf->data = REALLOC(buf->data, buf->capacity, buf->size);
93         buf->capacity = buf->size;
94      }
95      else {
96         FREE(buf->data);
97         buf->data = 0;
98         buf->capacity = 0;
99      }
100   }
101}
102
103#define util_dynarray_append(buf, type, v) do {type __v = (v); memcpy(util_dynarray_grow((buf), sizeof(type)), &__v, sizeof(type));} while(0)
104#define util_dynarray_top_ptr(buf, type) (type*)((char*)(buf)->data + (buf)->size - sizeof(type))
105#define util_dynarray_top(buf, type) *util_dynarray_top_ptr(buf, type)
106#define util_dynarray_pop_ptr(buf, type) (type*)((char*)(buf)->data + ((buf)->size -= sizeof(type)))
107#define util_dynarray_pop(buf, type) *util_dynarray_pop_ptr(buf, type)
108#define util_dynarray_contains(buf, type) ((buf)->size >= sizeof(type))
109#define util_dynarray_element(buf, type, idx) ((type*)(buf)->data + (idx))
110#define util_dynarray_begin(buf) ((buf)->data)
111#define util_dynarray_end(buf) ((void*)util_dynarray_element((buf), char, (buf)->size))
112
113#endif /* U_DYNARRAY_H */
114
115