Replaced arena

This commit is contained in:
2026-06-06 18:22:23 -05:00
parent 7c1b0ab290
commit 8f85b33696
2 changed files with 62 additions and 69 deletions
+16 -28
View File
@@ -23,16 +23,7 @@ SOFTWARE.
#ifndef CI2_ARENA_H
#define CI2_ARENA_H
#include "../ci2_platform.h"
#include "../error/ci2_exception.h"
enum
{
DEFAULT = 0, /* default: fail-handler (throws) + zero */
SOFT_FAIL = 1u << 0, /* on failure return NULL */
HARD_FAIL = 1u << 1, /* on failure call abort() */
NO_ZERO = 1u << 2, /* do not zero memory on success */
};
#include <stddef.h>
struct Arena
{
@@ -41,27 +32,24 @@ struct Arena
};
typedef struct Arena Arena;
/* Forward definition of an exception */
CI2_API struct Exception arena_oom;
/* Initialize an Arena with an existing buffer */
extern void
arena_back(struct Arena* a, char* buf, ptrdiff_t len);
/* Initialize an Arena from a buffer. */
CI2_API void
arena_init(struct Arena* a, void* buf, ptrdiff_t len);
/* Dynamically allocate an Arena */
CI2_API struct Arena
/* Allocate a new Arena */
extern struct Arena
arena_new(ptrdiff_t cap);
/* Get the remaining capicity of an arena. */
CI2_API ptrdiff_t
arena_size(struct Arena a);
/* Get the current capacity of an Arena */
extern ptrdiff_t
arena_capacity(struct Arena a);
/* Make an allocation from an Arena. */
CI2_API void*
arena_alloc(struct Arena* a,
int flags,
ptrdiff_t size,
ptrdiff_t align,
ptrdiff_t count);
/* Make an allocation from an Arena and do not zero.*/
extern void*
arena_malloc(struct Arena* a, ptrdiff_t size, ptrdiff_t align, ptrdiff_t count);
/* Make an allocation from an Arena and zero.*/
extern void*
arena_calloc(struct Arena* a, ptrdiff_t size, ptrdiff_t align, ptrdiff_t count);
#endif // ci2_arena.h
+31 -26
View File
@@ -21,21 +21,22 @@ SOFTWARE.
* --------------------------------------------------------------------------*/
#include "../include/platform/mem/ci2_arena.h"
#include <string.h>
#include <assert.h>
#include <stdint.h>
#include <stdlib.h>
struct Exception arena_oom = {"Arena is out of memory!"};
#include <string.h>
/* Initialize an Arena from a buffer. */
/* Initialize an Arena with an existing buffer */
void
arena_init(struct Arena* a, void* buf, ptrdiff_t len)
arena_back(struct Arena* a, char* buf, ptrdiff_t len)
{
CI2_ASSERT(buf != NULL);
CI2_ASSERT(len > 0);
a->beg = (char*)buf;
a->end = (char*)buf + len;
assert(a != NULL);
assert(buf != NULL);
a->beg = buf;
a->end = buf + len;
}
/* Dynamically allocate an Arena */
/* Allocate a new Arena */
struct Arena
arena_new(ptrdiff_t cap)
{
@@ -45,36 +46,40 @@ arena_new(ptrdiff_t cap)
return a;
}
/* Get the remaining capicity of an arena. */
/* Get the current capacity of an Arena */
ptrdiff_t
arena_size(struct Arena a)
arena_capacity(struct Arena a)
{
ptrdiff_t res = a.end - a.beg;
return res;
}
/* Make an allocation from an Arena. */
/* Make an allocation from an Arena and do not zero.*/
void*
arena_alloc(struct Arena* a,
int flags,
ptrdiff_t size,
ptrdiff_t align,
ptrdiff_t count)
arena_calloc(struct Arena* a, ptrdiff_t size, ptrdiff_t align, ptrdiff_t count)
{
ptrdiff_t padding = -(uintptr_t)a->beg & (align - 1);
ptrdiff_t available = a->end - a->beg - padding;
if (available < 0 || count > available / size) {
if (flags & SOFT_FAIL)
return 0;
if (flags & HARD_FAIL)
CI2_DEBUG_TRAP();
CI2_RAISE(arena_oom);
return NULL;
}
void* p = a->beg + padding;
ptrdiff_t total = padding + count * size;
void* p = a->beg + total;
a->beg += total;
return flags & NO_ZERO ? p : memset(p, 0, total);
return memset(p, 0, total);
}
/* Make an allocation from an Arena and zero.*/
void*
arena_malloc(struct Arena* a, ptrdiff_t size, ptrdiff_t align, ptrdiff_t count)
{
ptrdiff_t padding = -(uintptr_t)a->beg & (align - 1);
ptrdiff_t available = a->end - a->beg - padding;
if (available < 0 || count > available / size) {
return NULL;
}
ptrdiff_t total = padding + count * size;
void* p = a->beg + total;
a->beg += total;
return p;
}