62 lines
1.1 KiB
C
62 lines
1.1 KiB
C
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#ifndef ARENA_H
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#define ARENA_H
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#include <stdbool.h>
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#include <stddef.h> // size_t
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typedef struct arena {
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char *data;
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size_t size;
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size_t cap;
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bool grow;
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} arena_t;
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/**
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* Allocate a new arena.
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* The underlying memory is allocated with mmap.
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*/
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arena_t arena_new();
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/**
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* Delete memory mapped for arena.
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* Should only be used with arenas from arena_new().
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*/
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void arena_delete(arena_t *a);
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/**
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* Attach an arena to an existing memory region.
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* The arena will not expand the region if space is exceeded.
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*/
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static inline arena_t arena_attach(void *ptr, size_t size)
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{
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return (arena_t) { .data = ptr, .size = 0, .cap = size, .grow = false };
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}
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/**
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* Detach an arena from an existing memory region.
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*/
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static inline void *arena_detatch(arena_t arena)
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{
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return arena.data;
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}
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/**
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* Reset an arena.
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*/
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void arena_reset(arena_t *a);
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/**
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* Allocate memory from an arena.
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* Returns NULL and sets errno on failure.
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*/
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void *arena_alloc(arena_t *a, size_t len);
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/**
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* Allocate and zero memory from an arena.
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* Returns NULL and sets errno on failure.
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*/
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void *arena_calloc(arena_t *a, size_t nmemb, size_t size);
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#endif
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