GLdc/containers/stack.c

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C
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#include <string.h>
#ifndef __APPLE__
#include <malloc.h>
#else
/* Linux + Kos define this, OSX does not, so just use malloc there */
#define memalign(x, size) malloc((size))
#endif
#include "stack.h"
void init_stack(Stack* stack, unsigned int element_size, unsigned int capacity) {
stack->size = 0;
stack->capacity = capacity;
stack->element_size = element_size;
stack->data = (unsigned char*) memalign(0x20, element_size * capacity);
}
void* stack_top(Stack* stack) {
return &stack->data[(stack->size - 1) * stack->element_size];
}
void* stack_replace(Stack* stack, const void* element) {
memcpy(stack->data + ((stack->size - 1) * stack->element_size), element, stack->element_size);
return stack_top(stack);
}
void* stack_push(Stack* stack, const void* element) {
if(stack->size + 1 == stack->capacity) {
return NULL;
}
memcpy(stack->data + (stack->size * stack->element_size), element, stack->element_size);
stack->size++;
return stack_top(stack);
}
void stack_pop(Stack* stack) {
if(stack->size == 0) {
return;
}
stack->size--;
}