freebsd-dev/gnu/lib/libmalloc/malloc.h
1994-08-04 20:53:14 +00:00

262 lines
7.6 KiB
C

/* Declarations for `malloc' and friends.
Copyright 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
Written May 1989 by Mike Haertel.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.
The author may be reached (Email) at the address mike@ai.mit.edu,
or (US mail) as Mike Haertel c/o Free Software Foundation. */
#ifndef _MALLOC_H
#define _MALLOC_H 1
#ifdef _MALLOC_INTERNAL
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#if defined(_LIBC) || defined(STDC_HEADERS) || defined(USG)
#include <string.h>
#else
#ifndef memset
#define memset(s, zero, n) bzero ((s), (n))
#endif
#ifndef memcpy
#define memcpy(d, s, n) bcopy ((s), (d), (n))
#endif
#ifndef memmove
#define memmove(d, s, n) bcopy ((s), (d), (n))
#endif
#endif
#if defined(__GNU_LIBRARY__) || defined(__STDC__)
#include <limits.h>
#else
#define CHAR_BIT 8
#endif
#endif /* _MALLOC_INTERNAL. */
#ifdef __cplusplus
extern "C"
{
#endif
#if defined (__cplusplus) || (defined (__STDC__) && __STDC__)
#undef __GNU_P
#define __GNU_P(args) args
#undef __ptr_t
#define __ptr_t void *
#else /* Not C++ or ANSI C. */
#undef __GNU_P
#define __GNU_P(args) ()
#undef const
#define const
#undef __ptr_t
#define __ptr_t char *
#endif /* C++ or ANSI C. */
#ifdef __STDC__
#include <stddef.h>
#else
#undef size_t
#define size_t unsigned int
#undef ptrdiff_t
#define ptrdiff_t int
#endif
#ifndef NULL
#define NULL 0
#endif
/* Allocate SIZE bytes of memory. */
extern __ptr_t malloc __GNU_P ((size_t __size));
/* Re-allocate the previously allocated block
in __ptr_t, making the new block SIZE bytes long. */
extern __ptr_t realloc __GNU_P ((__ptr_t __ptr, size_t __size));
/* Allocate NMEMB elements of SIZE bytes each, all initialized to 0. */
extern __ptr_t calloc __GNU_P ((size_t __nmemb, size_t __size));
/* Free a block allocated by `malloc', `realloc' or `calloc'. */
extern void free __GNU_P ((__ptr_t __ptr));
/* Allocate SIZE bytes allocated to ALIGNMENT bytes. */
extern __ptr_t memalign __GNU_P ((size_t __alignment, size_t __size));
/* Allocate SIZE bytes on a page boundary. */
extern __ptr_t valloc __GNU_P ((size_t __size));
#ifdef _MALLOC_INTERNAL
/* The allocator divides the heap into blocks of fixed size; large
requests receive one or more whole blocks, and small requests
receive a fragment of a block. Fragment sizes are powers of two,
and all fragments of a block are the same size. When all the
fragments in a block have been freed, the block itself is freed. */
#define INT_BIT (CHAR_BIT * sizeof(int))
#define BLOCKLOG (INT_BIT > 16 ? 12 : 9)
#define BLOCKSIZE (1 << BLOCKLOG)
#define BLOCKIFY(SIZE) (((SIZE) + BLOCKSIZE - 1) / BLOCKSIZE)
/* Determine the amount of memory spanned by the initial heap table
(not an absolute limit). */
#define HEAP (INT_BIT > 16 ? 4194304 : 65536)
/* Number of contiguous free blocks allowed to build up at the end of
memory before they will be returned to the system. */
#define FINAL_FREE_BLOCKS 8
/* Data structure giving per-block information. */
typedef union
{
/* Heap information for a busy block. */
struct
{
/* Zero for a large block, or positive giving the
logarithm to the base two of the fragment size. */
int type;
union
{
struct
{
size_t nfree; /* Free fragments in a fragmented block. */
size_t first; /* First free fragment of the block. */
} frag;
/* Size (in blocks) of a large cluster. */
size_t size;
} info;
} busy;
/* Heap information for a free block
(that may be the first of a free cluster). */
struct
{
size_t size; /* Size (in blocks) of a free cluster. */
size_t next; /* Index of next free cluster. */
size_t prev; /* Index of previous free cluster. */
} free;
} malloc_info;
/* Pointer to first block of the heap. */
extern char *_heapbase;
/* Table indexed by block number giving per-block information. */
extern malloc_info *_heapinfo;
/* Address to block number and vice versa. */
#define BLOCK(A) (((char *) (A) - _heapbase) / BLOCKSIZE + 1)
#define ADDRESS(B) ((__ptr_t) (((B) - 1) * BLOCKSIZE + _heapbase))
/* Current search index for the heap table. */
extern size_t _heapindex;
/* Limit of valid info table indices. */
extern size_t _heaplimit;
/* Doubly linked lists of free fragments. */
struct list
{
struct list *next;
struct list *prev;
};
/* Free list headers for each fragment size. */
extern struct list _fraghead[];
/* List of blocks allocated with `memalign' (or `valloc'). */
struct alignlist
{
struct alignlist *next;
__ptr_t aligned; /* The address that memaligned returned. */
__ptr_t exact; /* The address that malloc returned. */
};
extern struct alignlist *_aligned_blocks;
/* Instrumentation. */
extern size_t _chunks_used;
extern size_t _bytes_used;
extern size_t _chunks_free;
extern size_t _bytes_free;
/* Internal version of `free' used in `morecore' (malloc.c). */
extern void _free_internal __GNU_P ((__ptr_t __ptr));
#endif /* _MALLOC_INTERNAL. */
/* Underlying allocation function; successive calls should
return contiguous pieces of memory. */
extern __ptr_t (*__morecore) __GNU_P ((ptrdiff_t __size));
/* Default value of `__morecore'. */
extern __ptr_t __default_morecore __GNU_P ((ptrdiff_t __size));
/* If not NULL, this function is called after each time
`__morecore' is called to increase the data size. */
extern void (*__after_morecore_hook) __GNU_P ((void));
/* Nonzero if `malloc' has been called and done its initialization. */
extern int __malloc_initialized;
/* Hooks for debugging versions. */
extern void (*__free_hook) __GNU_P ((__ptr_t __ptr));
extern __ptr_t (*__malloc_hook) __GNU_P ((size_t __size));
extern __ptr_t (*__realloc_hook) __GNU_P ((__ptr_t __ptr, size_t __size));
/* Activate a standard collection of debugging hooks. */
extern int mcheck __GNU_P ((void (*__func) __GNU_P ((void))));
/* Activate a standard collection of tracing hooks. */
extern void mtrace __GNU_P ((void));
/* Statistics available to the user. */
struct mstats
{
size_t bytes_total; /* Total size of the heap. */
size_t chunks_used; /* Chunks allocated by the user. */
size_t bytes_used; /* Byte total of user-allocated chunks. */
size_t chunks_free; /* Chunks in the free list. */
size_t bytes_free; /* Byte total of chunks in the free list. */
};
/* Pick up the current statistics. */
extern struct mstats mstats __GNU_P ((void));
/* Call WARNFUN with a warning message when memory usage is high. */
extern void memory_warnings __GNU_P ((__ptr_t __start,
void (*__warnfun) __GNU_P ((__const char *))));
/* Relocating allocator. */
/* Allocate SIZE bytes, and store the address in *HANDLEPTR. */
extern __ptr_t r_alloc __GNU_P ((__ptr_t *__handleptr, size_t __size));
/* Free the storage allocated in HANDLEPTR. */
extern void r_alloc_free __GNU_P ((__ptr_t *__handleptr));
/* Adjust the block at HANDLEPTR to be SIZE bytes long. */
extern __ptr_t r_re_alloc __GNU_P ((__ptr_t *__handleptr, size_t __size));
#ifdef __cplusplus
}
#endif
#endif /* malloc.h */