1 /*
2 +----------------------------------------------------------------------+
3 | Zend Engine |
4 +----------------------------------------------------------------------+
5 | Copyright (c) 1998-2017 Zend Technologies Ltd. (http://www.zend.com) |
6 +----------------------------------------------------------------------+
7 | This source file is subject to version 2.00 of the Zend license, |
8 | that is bundled with this package in the file LICENSE, and is |
9 | available through the world-wide-web at the following url: |
10 | http://www.zend.com/license/2_00.txt. |
11 | If you did not receive a copy of the Zend license and are unable to |
12 | obtain it through the world-wide-web, please send a note to |
13 | license@zend.com so we can mail you a copy immediately. |
14 +----------------------------------------------------------------------+
15 | Authors: Andi Gutmans <andi@zend.com> |
16 | Zeev Suraski <zeev@zend.com> |
17 +----------------------------------------------------------------------+
18 */
19
20 /* $Id$ */
21
22 #ifndef ZEND_PTR_STACK_H
23 #define ZEND_PTR_STACK_H
24
25 typedef struct _zend_ptr_stack {
26 int top, max;
27 void **elements;
28 void **top_element;
29 zend_bool persistent;
30 } zend_ptr_stack;
31
32
33 #define PTR_STACK_BLOCK_SIZE 64
34
35 BEGIN_EXTERN_C()
36 ZEND_API void zend_ptr_stack_init(zend_ptr_stack *stack);
37 ZEND_API void zend_ptr_stack_init_ex(zend_ptr_stack *stack, zend_bool persistent);
38 ZEND_API void zend_ptr_stack_n_push(zend_ptr_stack *stack, int count, ...);
39 ZEND_API void zend_ptr_stack_n_pop(zend_ptr_stack *stack, int count, ...);
40 ZEND_API void zend_ptr_stack_destroy(zend_ptr_stack *stack);
41 ZEND_API void zend_ptr_stack_apply(zend_ptr_stack *stack, void (*func)(void *));
42 ZEND_API void zend_ptr_stack_clean(zend_ptr_stack *stack, void (*func)(void *), zend_bool free_elements);
43 ZEND_API int zend_ptr_stack_num_elements(zend_ptr_stack *stack);
END_EXTERN_C()44 END_EXTERN_C()
45
46 #define ZEND_PTR_STACK_RESIZE_IF_NEEDED(stack, count) \
47 if (stack->top+count > stack->max) { \
48 /* we need to allocate more memory */ \
49 do { \
50 stack->max += PTR_STACK_BLOCK_SIZE; \
51 } while (stack->top+count > stack->max); \
52 stack->elements = (void **) perealloc(stack->elements, (sizeof(void *) * (stack->max)), stack->persistent); \
53 stack->top_element = stack->elements+stack->top; \
54 }
55
56 /* Not doing this with a macro because of the loop unrolling in the element assignment.
57 Just using a macro for 3 in the body for readability sake. */
58 static zend_always_inline void zend_ptr_stack_3_push(zend_ptr_stack *stack, void *a, void *b, void *c)
59 {
60 #define ZEND_PTR_STACK_NUM_ARGS 3
61
62 ZEND_PTR_STACK_RESIZE_IF_NEEDED(stack, ZEND_PTR_STACK_NUM_ARGS)
63
64 stack->top += ZEND_PTR_STACK_NUM_ARGS;
65 *(stack->top_element++) = a;
66 *(stack->top_element++) = b;
67 *(stack->top_element++) = c;
68
69 #undef ZEND_PTR_STACK_NUM_ARGS
70 }
71
zend_ptr_stack_2_push(zend_ptr_stack * stack,void * a,void * b)72 static zend_always_inline void zend_ptr_stack_2_push(zend_ptr_stack *stack, void *a, void *b)
73 {
74 #define ZEND_PTR_STACK_NUM_ARGS 2
75
76 ZEND_PTR_STACK_RESIZE_IF_NEEDED(stack, ZEND_PTR_STACK_NUM_ARGS)
77
78 stack->top += ZEND_PTR_STACK_NUM_ARGS;
79 *(stack->top_element++) = a;
80 *(stack->top_element++) = b;
81
82 #undef ZEND_PTR_STACK_NUM_ARGS
83 }
84
zend_ptr_stack_3_pop(zend_ptr_stack * stack,void ** a,void ** b,void ** c)85 static zend_always_inline void zend_ptr_stack_3_pop(zend_ptr_stack *stack, void **a, void **b, void **c)
86 {
87 *a = *(--stack->top_element);
88 *b = *(--stack->top_element);
89 *c = *(--stack->top_element);
90 stack->top -= 3;
91 }
92
zend_ptr_stack_2_pop(zend_ptr_stack * stack,void ** a,void ** b)93 static zend_always_inline void zend_ptr_stack_2_pop(zend_ptr_stack *stack, void **a, void **b)
94 {
95 *a = *(--stack->top_element);
96 *b = *(--stack->top_element);
97 stack->top -= 2;
98 }
99
zend_ptr_stack_push(zend_ptr_stack * stack,void * ptr)100 static zend_always_inline void zend_ptr_stack_push(zend_ptr_stack *stack, void *ptr)
101 {
102 ZEND_PTR_STACK_RESIZE_IF_NEEDED(stack, 1)
103
104 stack->top++;
105 *(stack->top_element++) = ptr;
106 }
107
zend_ptr_stack_pop(zend_ptr_stack * stack)108 static zend_always_inline void *zend_ptr_stack_pop(zend_ptr_stack *stack)
109 {
110 stack->top--;
111 return *(--stack->top_element);
112 }
113
zend_ptr_stack_top(zend_ptr_stack * stack)114 static zend_always_inline void *zend_ptr_stack_top(zend_ptr_stack *stack)
115 {
116 return stack->elements[stack->top - 1];
117 }
118
119 #endif /* ZEND_PTR_STACK_H */
120
121 /*
122 * Local variables:
123 * tab-width: 4
124 * c-basic-offset: 4
125 * indent-tabs-mode: t
126 * End:
127 */
128
