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-rw-r--r--arena.h108
1 files changed, 0 insertions, 108 deletions
diff --git a/arena.h b/arena.h
deleted file mode 100644
index c99fc97..0000000
--- a/arena.h
+++ /dev/null
@@ -1,108 +0,0 @@
-#ifndef ARENA_H_
-#define ARENA_H_
-
-#include <stdlib.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <assert.h>
-
-typedef struct region region;
-
-struct region {
- region *next;
- size_t cap;
- size_t len;
- uintptr_t data[];
-};
-
-typedef struct {
- region *beg;
- region *end;
-} arena;
-
-void *arena_alloc(arena *a, size_t size);
-void arena_free(arena *a);
-void grow_da(void *slice, size_t size, arena *arena);
-
-
-#define new(a, t, c) (t *)arena_alloc(a, sizeof(t)*c)
-
-#define ARENA_REGION_DEFAULT_CAPACITY (8*1024);
-
-// from nullprogram
-#define push(slice, arena) \
- ((slice)->len >= (slice)->cap \
- ? grow(slice, sizeof(*(slice)->data), arena), \
- (slice)->data + (slice)->len++ \
- : (slice)->data + (slice)->len++)
-
-#endif //ARENA_H_
-
-#ifdef ARENA_IMPLEMENTATION
-
-region *new_region(size_t cap) {
- size_t size_bytes = sizeof(region) + sizeof(uintptr_t)*cap;
- region *r = (region *)malloc(size_bytes);
- assert(r);
- r->next = NULL;
- r->len = 0;
- r->cap = cap;
- return r;
-}
-
-void *arena_alloc(arena *a, size_t size_bytes) {
- size_t size = (size_bytes + sizeof(uintptr_t)-1)/sizeof(uintptr_t);
-
- if (a->end == NULL) {
- assert(a->beg == NULL);
- size_t capacity = ARENA_REGION_DEFAULT_CAPACITY;
- if (capacity < size) capacity = size;
- a->beg = new_region(capacity);
- a->end = a->beg;
- }
-
- while (a->end->len + size < a->end->cap && a->end->next != NULL) {
- a->end = a->end->next;
- }
-
- if (a->end->len + size > a->end->cap) {
- size_t capacity = ARENA_REGION_DEFAULT_CAPACITY;
- if (capacity < size) capacity = size;
- a->beg = new_region(capacity);
- a->end->next = new_region(capacity);
- a->end = a->end->next;
- }
-
- void *p = &a->end->data[a->end->len];
- a->end->len += size;
- return memset(p, 0, size);
-}
-
-void arena_free(arena *a) {
- region *r = a->beg;
- while (r != NULL) {
- region *r0 = r;
- r = r0->next;
- free(r0);
- }
-}
-
-void grow(void *slice, size_t size, arena *arena) {
- struct {
- void *data;
- size_t len;
- size_t cap;
- } replica;
- memcpy(&replica, slice, sizeof(replica));
-
- replica.cap = replica.cap ? replica.cap : 1;
- void *data = arena_alloc(arena, size*2*replica.cap);
- replica.cap *= 2;
- if (replica.len) {
- memcpy(data, replica.data, size*replica.len);
- }
- replica.data = data;
-
- memcpy(slice, &replica, sizeof(replica));
-}
-#endif // ARENA_IMPLEMENTATION