From 3cbb37a3ebe003d0792d6e2a7fdd16a3d0b04ebb Mon Sep 17 00:00:00 2001 From: Martin Michalec Date: Sun, 22 Feb 2026 01:34:57 +0300 Subject: add implementation --- include/cmmm/arena.h | 140 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 140 insertions(+) create mode 100644 include/cmmm/arena.h (limited to 'include/cmmm') diff --git a/include/cmmm/arena.h b/include/cmmm/arena.h new file mode 100644 index 0000000..07c9bef --- /dev/null +++ b/include/cmmm/arena.h @@ -0,0 +1,140 @@ +#ifndef INCLUDED__CMMM__ARENA__H +#define INCLUDED__CMMM__ARENA__H + +// NOTE(cmmm): this implementation assumes that allocations are made +// at the end, so that we can take advantage of checkpoints. The +// downside is that we can't allocate from previous chunks even if +// there is space left in them... + +// NOTE(cmmm): coalescing is nice, but while you're building an +// "object", it may be split across multiple chunks + +#include + +// #define CMMM__ARENA__NO_STDIO +// #define CMMM__ARENA__STRIP_VENDOR + +#ifndef CMMM__ARENA__FIRST_CHUNK_SIZE +#define CMMM__ARENA__FIRST_CHUNK_SIZE (4 << 10) +#endif + +#ifndef CMMM__ARENA__CHUNK_GROWTH_FACTOR +#define CMMM__ARENA__CHUNK_GROWTH_FACTOR 2 +#endif + +struct cmmm__arena__chunk { + struct cmmm__arena__chunk *next; + char *free; + char *end; + char data[]; +}; + +#define CMMM__ARENA struct cmmm__arena * +struct cmmm__arena { + struct cmmm__arena__chunk *head; + struct cmmm__arena__chunk *tail; +}; + +struct cmmm__arena__checkpoint { + struct cmmm__arena__chunk *tail; + char *free; +}; + +#ifndef ALIGNOF +#if __STDC_VERSION__ >= 202311L +#define ALIGNOF alignof +#elif __STDC_VERSION__ >= 201112L +#define ALIGNOF _Alignof +#else +#define ALIGNOF(O) offsetof (struct { char _; typeof (O) x; }, x) +#endif +#endif + +#define CMMM__ARENA__RESERVE( A, T) cmmm__arena__reserve ((A), sizeof (T), ALIGNOF (T)) +#define CMMM__ARENA__RESERVE_ARRAY( A, N, T) cmmm__arena__reserve ((A), (N)*sizeof (T), ALIGNOF (T)) +#define CMMM__ARENA__ALLOCATE( A, T) cmmm__arena__allocate ((A), sizeof (T), ALIGNOF (T)) +#define CMMM__ARENA__ALLOCATE_ARRAY( A, N, T) cmmm__arena__allocate ((A), (N)*sizeof (T), ALIGNOF (T)) +#define CMMM__ARENA__ALLOCATE_FAST( A, T) cmmm__arena__allocate_fast ((A), sizeof (T), ALIGNOF (T)) +#define CMMM__ARENA__ALLOCATE_ARRAY_FAST(A, N, T) cmmm__arena__allocate_fast ((A), (N)*sizeof (T), ALIGNOF (T)) +#define CMMM__ARENA__ZERO( A, T) cmmm__arena__zero ((A), sizeof (T), ALIGNOF (T)) +#define CMMM__ARENA__ZERO_ARRAY( A, N, T) cmmm__arena__zero ((A), (N)*sizeof (T), ALIGNOF (T)) +void *cmmm__arena__reserve (struct cmmm__arena *, size_t size, size_t alignment); +void *cmmm__arena__allocate (struct cmmm__arena *, size_t size, size_t alignment); +void *cmmm__arena__allocate_fast (struct cmmm__arena *, size_t size, size_t alignment); +void *cmmm__arena__zero (struct cmmm__arena *, size_t size, size_t alignment); + +size_t cmmm__arena__room (const struct cmmm__arena *, size_t alignment); +void *cmmm__arena__next_free (const struct cmmm__arena *, size_t alignment); + +#define CMMM__ARENA__COPY( A, F, T) cmmm__arena__copy ((A), (F), sizeof (T), ALIGNOF (T)) +#define CMMM__ARENA__COPY_ARRAY(A, F, N, T) cmmm__arena__copy ((A), (F), (N)*sizeof (T), ALIGNOF (T)) +void *cmmm__arena__copy (struct cmmm__arena *, const void *, size_t size, size_t alignment); +char *cmmm__arena__copy_cstr (struct cmmm__arena *, const char *); + +void cmmm__arena__reset (struct cmmm__arena *); + +struct cmmm__arena__checkpoint cmmm__arena__checkpoint (struct cmmm__arena *); +size_t cmmm__arena__checkpoint__size_from (struct cmmm__arena__checkpoint); +void cmmm__arena__rollback_to (struct cmmm__arena *, struct cmmm__arena__checkpoint); +void *cmmm__arena__coalesce_from (struct cmmm__arena *, struct cmmm__arena__checkpoint); +void *cmmm__arena__coalesce_from_fast (struct cmmm__arena *, struct cmmm__arena__checkpoint, size_t size); + +void cmmm__arena__trim (struct cmmm__arena *); +void cmmm__arena__free (struct cmmm__arena *); + +#ifndef CMMM__ARENA__NO_STDIO +#include +char *cmmm__arena__printf (struct cmmm__arena *, const char *format, ...); +char *cmmm__arena__vprintf (struct cmmm__arena *, const char *format, va_list ap); +#endif + +#ifdef CMMM__ARENA__STRIP_VENDOR +#define ARENA__NO_STDIO CMMM__ARENA__NO_STDIO +#define ARENA__STRIP_VENDOR CMMM__ARENA__STRIP_VENDOR + +#define ARENA__FIRST_CHUNK_SIZE CMMM__ARENA__FIRST_CHUNK_SIZE +#define ARENA__CHUNK_GROWTH_FACTOR CMMM__ARENA__CHUNK_GROWTH_FACTOR + +#define arena__chunk cmmm__arena__chunk +#define ARENA CMMM__ARENA +#define arena__checkpoint cmmm__arena__checkpoint + +#define ARENA__RESERVE CMMM__ARENA__RESERVE +#define ARENA__RESERVE_ARRAY CMMM__ARENA__RESERVE_ARRAY +#define ARENA__ALLOCATE CMMM__ARENA__ALLOCATE +#define ARENA__ALLOCATE_ARRAY CMMM__ARENA__ALLOCATE_ARRAY +#define ARENA__ALLOCATE_FAST CMMM__ARENA__ALLOCATE_FAST +#define ARENA__ALLOCATE_ARRAY_FAST CMMM__ARENA__ALLOCATE_ARRAY_FAST +#define ARENA__ZERO CMMM__ARENA__ZERO +#define ARENA__ZERO_ARRAY CMMM__ARENA__ZERO_ARRAY +#define arena__reserve cmmm__arena__reserve +#define arena__allocate cmmm__arena__allocate +#define arena__allocate_fast cmmm__arena__allocate_fast +#define arena__zero cmmm__arena__zero + +#define arena__room cmmm__arena__room +#define arena__next_free cmmm__arena__next_free + +#define ARENA__COPY CMMM__ARENA__COPY +#define ARENA__COPY_ARRAY CMMM__ARENA__COPY_ARRAY +#define arena__copy cmmm__arena__copy +#define arena__copy_cstr cmmm__arena__copy_cstr + +#define arena__reset cmmm__arena__reset + +#define arena__checkpoint cmmm__arena__checkpoint +#define arena__rollback_to cmmm__arena__rollback_to +#define arena__size_from cmmm__arena__size_from +#define arena__coalesce_from cmmm__arena__coalesce_from +#define arena__coalesce_from_fast cmmm__arena__coalesce_from_fast + +#define arena__trim cmmm__arena__trim +#define arena__free cmmm__arena__free + +#ifndef CMMM__ARENA__NO_STDIO +#define arena__printf cmmm__arena__printf +#define arena__vprintf cmmm__arena__vprintf +#endif +#endif + +#endif // INCLUDED__CMMM__ARENA__H -- cgit v1.3