Files
cig/buffer_allocator.c
T

64 lines
1.7 KiB
C

#include "cig.h"
void *buffer_allocator_alloc(buffer_allocator_t *this, size_t bytes) {
size_t address_of_new_data = (size_t) &this->data[this->size];
size_t offset = address_of_new_data % MAX_ALIGN;
size_t new_size = this->size + offset + bytes;
if (new_size > this->capacity) {
return NULL;
}
this->size += offset;
void *ptr = &this->data[this->size];
this->size = new_size;
return ptr;
}
void *buffer_allocator_resize(buffer_allocator_t *this, void *old_ptr, size_t bytes) {
void *new_ptr = buffer_allocator_alloc(this, bytes);
if (new_ptr == NULL) {
return NULL;
}
for (size_t i = 0; i < bytes; i++) {
unsigned char *new_ptr_b = (unsigned char *)new_ptr;
unsigned char *old_ptr_b = (unsigned char *)old_ptr;
new_ptr_b[i] = old_ptr_b[i];
}
return new_ptr;
}
void buffer_allocator_reset(buffer_allocator_t *this) {
this->size = 0;
}
static void *buffer_alloc(void *this, size_t bytes, const char *file, int line) {
(void)file;
(void)line;
return buffer_allocator_alloc((buffer_allocator_t *)this, bytes);
}
static void *buffer_resize(void *this, void *old_ptr, size_t bytes, const char *file, int line) {
(void)file;
(void)line;
return buffer_allocator_resize(this, old_ptr, bytes);
}
static void buffer_free(void *this, void *ptr, const char *file, int line) {
(void)this;
(void)ptr;
(void)file;
(void)line;
}
static const allocator_vtbl_t buffer_vtbl = {
.alloc = buffer_alloc,
.resize = buffer_resize,
.free = buffer_free,
};
allocator_t buffer_allocator_interface(buffer_allocator_t *this) {
return (allocator_t) {
.this=this,
.vtbl=&buffer_vtbl,
};
}