rizin/librz/util/stack.c
2021-11-25 15:44:28 +08:00

78 lines
1.4 KiB
C

// SPDX-FileCopyrightText: 2007-2020 ret2libc <sirmy15@gmail.com>
// SPDX-License-Identifier: LGPL-3.0-only
#include <rz_util.h>
RZ_API RzStack *rz_stack_new(ut32 n) {
RzStack *s = RZ_NEW0(RzStack);
if (!s) {
return NULL;
}
s->elems = RZ_NEWS0(void *, n);
if (!s->elems) {
free(s);
return NULL;
}
s->n_elems = n;
s->top = -1;
return s;
}
RZ_API RzStack *rz_stack_newf(ut32 n, RzStackFree f) {
RzStack *s = rz_stack_new(n);
if (s) {
s->free = f;
}
return s;
}
RZ_API void rz_stack_free(RzStack *s) {
if (s) {
if (s->free) {
int i;
for (i = 0; i <= s->top; i++) {
s->free(s->elems[i]);
}
}
free(s->elems);
free(s);
}
}
RZ_API bool rz_stack_push(RzStack *s, void *el) {
if (s->top == s->n_elems - 1) {
/* reallocate the stack */
s->n_elems *= 2;
void **elems = realloc(s->elems, s->n_elems * sizeof(void *));
if (!elems) {
return false;
}
s->elems = elems;
}
s->top++;
s->elems[s->top] = el;
return true;
}
// the caller should be take care of the object returned
RZ_API void *rz_stack_pop(RzStack *s) {
if (s->top == -1) {
return NULL;
}
void *res = s->elems[s->top];
s->top--;
return res;
}
RZ_API bool rz_stack_is_empty(RzStack *s) {
return s->top == -1;
}
RZ_API size_t rz_stack_size(RzStack *s) {
return (size_t)(s->top + 1);
}
RZ_API void *rz_stack_peek(RzStack *s) {
return rz_stack_is_empty(s) ? NULL : s->elems[s->top];
}