1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2019-2023 Broadcom
3 * All rights reserved.
4 */
5
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <stdbool.h>
9 #include <stdint.h>
10 #include <errno.h>
11 #include "stack.h"
12
13 #define STACK_EMPTY -1
14
15 /* Initialize stack
16 */
17 int
stack_init(int num_entries,uint32_t * items,struct stack * st)18 stack_init(int num_entries, uint32_t *items, struct stack *st)
19 {
20 if (items == NULL || st == NULL)
21 return -EINVAL;
22
23 st->max = num_entries;
24 st->top = STACK_EMPTY;
25 st->items = items;
26
27 return 0;
28 }
29
30 /*
31 * Return the address of the items
32 */
stack_items(struct stack * st)33 uint32_t *stack_items(struct stack *st)
34 {
35 return st->items;
36 }
37
38 /* Return the size of the stack
39 */
40 int32_t
stack_size(struct stack * st)41 stack_size(struct stack *st)
42 {
43 return st->top + 1;
44 }
45
46 /* Check if the stack is empty
47 */
48 bool
stack_is_empty(struct stack * st)49 stack_is_empty(struct stack *st)
50 {
51 return st->top == STACK_EMPTY;
52 }
53
54 /* Check if the stack is full
55 */
56 bool
stack_is_full(struct stack * st)57 stack_is_full(struct stack *st)
58 {
59 return st->top == st->max - 1;
60 }
61
62 /* Add element x to the stack
63 */
64 int
stack_push(struct stack * st,uint32_t x)65 stack_push(struct stack *st, uint32_t x)
66 {
67 if (stack_is_full(st))
68 return -EOVERFLOW;
69
70 /* add an element and increments the top index
71 */
72 st->items[++st->top] = x;
73
74 return 0;
75 }
76
77 /* Pop top element x from the stack and return
78 * in user provided location.
79 */
80 int
stack_pop(struct stack * st,uint32_t * x)81 stack_pop(struct stack *st, uint32_t *x)
82 {
83 if (stack_is_empty(st))
84 return -ENOENT;
85
86 *x = st->items[st->top];
87 st->top--;
88
89 return 0;
90 }
91
92 /* Dump the stack
93 */
stack_dump(struct stack * st)94 void stack_dump(struct stack *st)
95 {
96 int i, j;
97
98 printf("top=%d\n", st->top);
99 printf("max=%d\n", st->max);
100
101 if (st->top == -1) {
102 printf("stack is empty\n");
103 return;
104 }
105
106 for (i = 0; i < st->max + 7 / 8; i++) {
107 printf("item[%d] 0x%08x", i, st->items[i]);
108
109 for (j = 0; j < 7; j++) {
110 if (i++ < st->max - 1)
111 printf(" 0x%08x", st->items[i]);
112 }
113 printf("\n");
114 }
115 }
116