1 /*
2 +----------------------------------------------------------------------+
3 | Zend Engine |
4 +----------------------------------------------------------------------+
5 | Copyright (c) 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@php.net> |
16 | Zeev Suraski <zeev@php.net> |
17 +----------------------------------------------------------------------+
18 */
19
20 #ifndef ZEND_PTR_STACK_H
21 #define ZEND_PTR_STACK_H
22
23 typedef struct _zend_ptr_stack {
24 int top, max;
25 void **elements;
26 void **top_element;
27 bool persistent;
28 } zend_ptr_stack;
29
30
31 #define PTR_STACK_BLOCK_SIZE 64
32
33 BEGIN_EXTERN_C()
34 ZEND_API void zend_ptr_stack_init(zend_ptr_stack *stack);
35 ZEND_API void zend_ptr_stack_init_ex(zend_ptr_stack *stack, bool persistent);
36 ZEND_API void zend_ptr_stack_n_push(zend_ptr_stack *stack, int count, ...);
37 ZEND_API void zend_ptr_stack_n_pop(zend_ptr_stack *stack, int count, ...);
38 ZEND_API void zend_ptr_stack_destroy(zend_ptr_stack *stack);
39 ZEND_API void zend_ptr_stack_apply(zend_ptr_stack *stack, void (*func)(void *));
40 ZEND_API void zend_ptr_stack_reverse_apply(zend_ptr_stack *stack, void (*func)(void *));
41 ZEND_API void zend_ptr_stack_clean(zend_ptr_stack *stack, void (*func)(void *), bool free_elements);
42 ZEND_API int zend_ptr_stack_num_elements(zend_ptr_stack *stack);
END_EXTERN_C()43 END_EXTERN_C()
44
45 #define ZEND_PTR_STACK_RESIZE_IF_NEEDED(stack, count) \
46 if (stack->top+count > stack->max) { \
47 /* we need to allocate more memory */ \
48 do { \
49 stack->max += PTR_STACK_BLOCK_SIZE; \
50 } while (stack->top+count > stack->max); \
51 stack->elements = (void **) safe_perealloc(stack->elements, sizeof(void *), (stack->max), 0, stack->persistent); \
52 stack->top_element = stack->elements+stack->top; \
53 }
54
55 /* Not doing this with a macro because of the loop unrolling in the element assignment.
56 Just using a macro for 3 in the body for readability sake. */
57 static zend_always_inline void zend_ptr_stack_3_push(zend_ptr_stack *stack, void *a, void *b, void *c)
58 {
59 #define ZEND_PTR_STACK_NUM_ARGS 3
60
61 ZEND_PTR_STACK_RESIZE_IF_NEEDED(stack, ZEND_PTR_STACK_NUM_ARGS)
62
63 stack->top += ZEND_PTR_STACK_NUM_ARGS;
64 *(stack->top_element++) = a;
65 *(stack->top_element++) = b;
66 *(stack->top_element++) = c;
67
68 #undef ZEND_PTR_STACK_NUM_ARGS
69 }
70
zend_ptr_stack_2_push(zend_ptr_stack * stack,void * a,void * b)71 static zend_always_inline void zend_ptr_stack_2_push(zend_ptr_stack *stack, void *a, void *b)
72 {
73 #define ZEND_PTR_STACK_NUM_ARGS 2
74
75 ZEND_PTR_STACK_RESIZE_IF_NEEDED(stack, ZEND_PTR_STACK_NUM_ARGS)
76
77 stack->top += ZEND_PTR_STACK_NUM_ARGS;
78 *(stack->top_element++) = a;
79 *(stack->top_element++) = b;
80
81 #undef ZEND_PTR_STACK_NUM_ARGS
82 }
83
zend_ptr_stack_3_pop(zend_ptr_stack * stack,void ** a,void ** b,void ** c)84 static zend_always_inline void zend_ptr_stack_3_pop(zend_ptr_stack *stack, void **a, void **b, void **c)
85 {
86 *a = *(--stack->top_element);
87 *b = *(--stack->top_element);
88 *c = *(--stack->top_element);
89 stack->top -= 3;
90 }
91
zend_ptr_stack_2_pop(zend_ptr_stack * stack,void ** a,void ** b)92 static zend_always_inline void zend_ptr_stack_2_pop(zend_ptr_stack *stack, void **a, void **b)
93 {
94 *a = *(--stack->top_element);
95 *b = *(--stack->top_element);
96 stack->top -= 2;
97 }
98
zend_ptr_stack_push(zend_ptr_stack * stack,void * ptr)99 static zend_always_inline void zend_ptr_stack_push(zend_ptr_stack *stack, void *ptr)
100 {
101 ZEND_PTR_STACK_RESIZE_IF_NEEDED(stack, 1)
102
103 stack->top++;
104 *(stack->top_element++) = ptr;
105 }
106
zend_ptr_stack_pop(zend_ptr_stack * stack)107 static zend_always_inline void *zend_ptr_stack_pop(zend_ptr_stack *stack)
108 {
109 stack->top--;
110 return *(--stack->top_element);
111 }
112
zend_ptr_stack_top(zend_ptr_stack * stack)113 static zend_always_inline void *zend_ptr_stack_top(zend_ptr_stack *stack)
114 {
115 return stack->elements[stack->top - 1];
116 }
117
118 #endif /* ZEND_PTR_STACK_H */
119
