borrow allocator implementation

This commit is contained in:
2025-10-08 22:16:31 +02:00
parent 6ffbc05f52
commit a20833f4ee
3 changed files with 120 additions and 13 deletions
+91 -10
View File
@@ -1,25 +1,106 @@
#include "allocator.h"
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <stdbool.h>
void *borrow_allcoator_alloc(borrow_allocator_t *this, size_t bytes) {
void *borrow_allocator_alloc_func(borrow_allocator_t *this, size_t bytes, const char *file, int line) {
linked_allocation_node_t *node = malloc(sizeof(*this->head) + bytes);
if (node == NULL) { return NULL; }
node->file = file;
node->line = line;
node->prev = NULL;
node->next = this->head;
if (this->head != NULL) {
assert(this->head->prev == NULL);
this->head->prev = node;
}
this->head = node;
return &node->data;
}
// WARNING: it is important to consider the case where the old_node is the head
// node.
void *borrow_allocator_resize_func(borrow_allocator_t *this, void *old_ptr, size_t bytes, const char *file, int line) {
linked_allocation_node_t *old_node = PTR_FROM_FIELD_PTR(linked_allocation_node_t, data, old_ptr);
linked_allocation_node_t *new_node = realloc(old_node, sizeof(*old_node) + bytes);
if (new_node == NULL) { return NULL; }
new_node->file = file;
new_node->line = line;
if (this->head == old_node) {
assert(new_node->prev == NULL);
this->head = new_node;
}
if (new_node->prev != NULL) { new_node->prev->next = new_node; }
if (new_node->next != NULL) { new_node->next->prev = new_node; }
return &new_node->data;
}
void *borrow_allcoator_resize(borrow_allocator_t *this, void *old_ptr, size_t bytes) {
linked_allocation_node_t *old_node = PTR_FROM_FIELD_PTR(linked_allocation_node_t, data, old_ptr);
// TODO: update the links
void borrow_allocator_free(borrow_allocator_t *this, void *old_ptr) {
linked_allocation_node_t *node = PTR_FROM_FIELD_PTR(linked_allocation_node_t, data, old_ptr);
if (node->prev != NULL) { node->prev->next = node->next; }
if (node->next != NULL) { node->next->prev = node->prev; }
if (this->head == node) {
assert(node->prev == NULL);
if (node->next != NULL) { assert(node->next->prev == NULL); }
this->head = node->next;
}
free(node);
}
void borrow_allcoator_free(borrow_allocator_t *this, void *old_ptr) {
linked_allocation_node_t *old_node = PTR_FROM_FIELD_PTR(linked_allocation_node_t, data, old_ptr);
// TODO: update the links
free(old_node);
void borrow_allocator_reset(borrow_allocator_t *this) {
if (this->head == NULL) {
return;
}
assert(this->head->prev == NULL);
void *prev = NULL;
for (linked_allocation_node_t *node = this->head; node != NULL; node = node->next) {
free(prev);
prev = node;
}
free(prev);
this->head = NULL;
}
size_t borrow_allocator_count_allocations(borrow_allocator_t *this) {
size_t output = 0;
for (linked_allocation_node_t *node = this->head; node != NULL; node = node->next) {
output++;
}
return output;
}
static void *borrow_alloc(void *this, size_t bytes, const char *file, int line) {
return borrow_allocator_alloc_func(this, bytes, file, line);
}
static void *borrow_resize(void *this, void *old_ptr, size_t bytes, const char *file, int line) {
return borrow_allocator_resize_func(this, old_ptr, bytes, file, line);
}
static void borrow_free(void *this, void *ptr, const char *file, int line) {
(void)file;
(void)line;
borrow_allocator_free(this, ptr);
}
static const allocator_vtbl_t borrow_vtbl = {
.alloc = borrow_alloc,
.resize = borrow_resize,
.free = borrow_free,
};
allocator_t borrow_allocator_interface(borrow_allocator_t *this) {
return (allocator_t) {
.this=this,
.vtbl=&borrow_vtbl,
};
}
void borrow_allocator_assert_all_freed(borrow_allocator_t *this) {
bool should_crash = false;
for (linked_allocation_node_t *curr = this->head; curr != NULL; curr = curr->next) {
fprintf(stderr, "%s:%d: allocation not freed\n", curr->file, curr->line);
}
if (should_crash) {
exit(1);
}
}