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/* DO NOT EDIT THIS FILE -- it is automagically generated. -*- C -*- */
#define _MALLOC_INTERNAL
/* The malloc headers and source files from the C library follow here. */
/* 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
/* Harmless, gets __GNU_LIBRARY__ defined.
We must do this before #defining size_t and ptrdiff_t
because <stdio.h> tries to typedef them on some systems. */
#include <stdio.h>
#endif
#ifdef __cplusplus
extern "C"
{
#endif
#if defined (__cplusplus) || (defined (__STDC__) && __STDC__)
#undef __P
#define __P(args) args
#undef __ptr_t
#define __ptr_t void *
#else /* Not C++ or ANSI C. */
#undef __P
#define __P(args) ()
#undef const
#define const
#undef __ptr_t
#define __ptr_t char *
#endif /* C++ or ANSI C. */
#ifndef NULL
#define NULL 0
#endif
#ifdef __STDC__
#include <stddef.h>
#else
#undef size_t
#define size_t unsigned int
#undef ptrdiff_t
#define ptrdiff_t int
#endif
/* Allocate SIZE bytes of memory. */
extern __ptr_t malloc __P ((size_t __size));
/* Re-allocate the previously allocated block
in __ptr_t, making the new block SIZE bytes long. */
extern __ptr_t realloc __P ((__ptr_t __ptr, size_t __size));
/* Allocate NMEMB elements of SIZE bytes each, all initialized to 0. */
extern __ptr_t calloc __P ((size_t __nmemb, size_t __size));
/* Free a block allocated by `malloc', `realloc' or `calloc'. */
extern void free __P ((__ptr_t __ptr));
/* Allocate SIZE bytes allocated to ALIGNMENT bytes. */
extern __ptr_t memalign __P ((size_t __alignment, size_t __size));
/* Allocate SIZE bytes on a page boundary. */
extern __ptr_t valloc __P ((size_t __size));
#ifdef _MALLOC_INTERNAL
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#if defined(__GNU_LIBRARY__) || 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
/* 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
/* Where to start searching the free list when looking for new memory.
The two possible values are 0 and _heapindex. Starting at 0 seems
to reduce total memory usage, while starting at _heapindex seems to
run faster. */
#define MALLOC_SEARCH_START _heapindex
/* 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 __P ((__ptr_t __ptr));
#endif /* _MALLOC_INTERNAL. */
/* Underlying allocation function; successive calls should
return contiguous pieces of memory. */
extern __ptr_t (*__morecore) __P ((ptrdiff_t __size));
/* Default value of `__morecore'. */
extern __ptr_t __default_morecore __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) __P ((void));
/* Nonzero if `malloc' has been called and done its initialization. */
extern int __malloc_initialized;
/* Hooks for debugging versions. */
extern void (*__free_hook) __P ((__ptr_t __ptr));
extern __ptr_t (*__malloc_hook) __P ((size_t __size));
extern __ptr_t (*__realloc_hook) __P ((__ptr_t __ptr, size_t __size));
/* Activate a standard collection of debugging hooks. */
extern int mcheck __P ((void (*__func) __P ((void))));
/* Activate a standard collection of tracing hooks. */
extern void mtrace __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 __P ((void));
/* Call WARNFUN with a warning message when memory usage is high. */
extern void memory_warnings __P ((__ptr_t __start,
void (*__warnfun) __P ((__const char *))));
/* Relocating allocator. */
/* Allocate SIZE bytes, and store the address in *HANDLEPTR. */
extern __ptr_t r_alloc __P ((__ptr_t *__handleptr, size_t __size));
/* Free the storage allocated in HANDLEPTR. */
extern void r_alloc_free __P ((__ptr_t *__handleptr));
/* Adjust the block at HANDLEPTR to be SIZE bytes long. */
extern __ptr_t r_re_alloc __P ((__ptr_t *__handleptr, size_t __size));
#ifdef __cplusplus
}
#endif
#endif /* malloc.h */
/* Memory allocator `malloc'.
Copyright 1990, 1991, 1992 Free Software Foundation
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_INTERNAL
#define _MALLOC_INTERNAL
#include <malloc.h>
#endif
/* How to really get more memory. */
__ptr_t (*__morecore) __P ((ptrdiff_t __size)) = __default_morecore;
/* Debugging hook for `malloc'. */
__ptr_t (*__malloc_hook) __P ((size_t __size));
/* Pointer to the base of the first block. */
char *_heapbase;
/* Block information table. Allocated with align/__free (not malloc/free). */
malloc_info *_heapinfo;
/* Number of info entries. */
static size_t heapsize;
/* Search index in the info table. */
size_t _heapindex;
/* Limit of valid info table indices. */
size_t _heaplimit;
/* Free lists for each fragment size. */
struct list _fraghead[BLOCKLOG];
/* Instrumentation. */
size_t _chunks_used;
size_t _bytes_used;
size_t _chunks_free;
size_t _bytes_free;
/* Are you experienced? */
int __malloc_initialized;
void (*__after_morecore_hook) __P ((void));
/* Aligned allocation. */
static __ptr_t align __P ((size_t));
static __ptr_t
align (size)
size_t size;
{
__ptr_t result;
unsigned long int adj;
result = (*__morecore) (size);
adj = (unsigned long int) ((unsigned long int) ((char *) result -
(char *) NULL)) % BLOCKSIZE;
if (adj != 0)
{
adj = BLOCKSIZE - adj;
(void) (*__morecore) (adj);
result = (char *) result + adj;
}
if (__after_morecore_hook)
(*__after_morecore_hook) ();
return result;
}
/* Set everything up and remember that we have. */
static int initialize __P ((void));
static int
initialize ()
{
heapsize = HEAP / BLOCKSIZE;
_heapinfo = (malloc_info *) align (heapsize * sizeof (malloc_info));
if (_heapinfo == NULL)
return 0;
memset (_heapinfo, 0, heapsize * sizeof (malloc_info));
_heapinfo[0].free.size = 0;
_heapinfo[0].free.next = _heapinfo[0].free.prev = 0;
_heapindex = 0;
_heapbase = (char *) _heapinfo;
__malloc_initialized = 1;
return 1;
}
/* Get neatly aligned memory, initializing or
growing the heap info table as necessary. */
static __ptr_t morecore __P ((size_t));
static __ptr_t
morecore (size)
size_t size;
{
__ptr_t result;
malloc_info *newinfo, *oldinfo;
size_t newsize;
result = align (size);
if (result == NULL)
return NULL;
/* Check if we need to grow the info table. */
if ((size_t) BLOCK ((char *) result + size) > heapsize)
{
newsize = heapsize;
while ((size_t) BLOCK ((char *) result + size) > newsize)
newsize *= 2;
newinfo = (malloc_info *) align (newsize * sizeof (malloc_info));
if (newinfo == NULL)
{
(*__morecore) (-size);
return NULL;
}
memset (newinfo, 0, newsize * sizeof (malloc_info));
memcpy (newinfo, _heapinfo, heapsize * sizeof (malloc_info));
oldinfo = _heapinfo;
newinfo[BLOCK (oldinfo)].busy.type = 0;
newinfo[BLOCK (oldinfo)].busy.info.size
= BLOCKIFY (heapsize * sizeof (malloc_info));
_heapinfo = newinfo;
_free_internal (oldinfo);
heapsize = newsize;
}
_heaplimit = BLOCK ((char *) result + size);
return result;
}
/* Allocate memory from the heap. */
__ptr_t
malloc (size)
size_t size;
{
__ptr_t result;
size_t block, blocks, lastblocks, start;
register size_t i;
struct list *next;
if (size == 0)
return NULL;
if (__malloc_hook != NULL)
return (*__malloc_hook) (size);
if (!__malloc_initialized)
if (!initialize ())
return NULL;
if (size < sizeof (struct list))
size = sizeof (struct list);
/* Determine the allocation policy based on the request size. */
if (size <= BLOCKSIZE / 2)
{
/* Small allocation to receive a fragment of a block.
Determine the logarithm to base two of the fragment size. */
register size_t log = 1;
--size;
while ((size /= 2) != 0)
++log;
/* Look in the fragment lists for a
free fragment of the desired size. */
next = _fraghead[log].next;
if (next != NULL)
{
/* There are free fragments of this size.
Pop a fragment out of the fragment list and return it.
Update the block's nfree and first counters. */
result = (__ptr_t) next;
next->prev->next = next->next;
if (next->next != NULL)
next->next->prev = next->prev;
block = BLOCK (result);
if (--_heapinfo[block].busy.info.frag.nfree != 0)
_heapinfo[block].busy.info.frag.first = (unsigned long int)
((unsigned long int) ((char *) next->next - (char *) NULL)
% BLOCKSIZE) >> log;
/* Update the statistics. */
++_chunks_used;
_bytes_used += 1 << log;
--_chunks_free;
_bytes_free -= 1 << log;
}
else
{
/* No free fragments of the desired size, so get a new block
and break it into fragments, returning the first. */
result = malloc (BLOCKSIZE);
if (result == NULL)
return NULL;
/* Link all fragments but the first into the free list. */
for (i = 1; i < (size_t) (BLOCKSIZE >> log); ++i)
{
next = (struct list *) ((char *) result + (i << log));
next->next = _fraghead[log].next;
next->prev = &_fraghead[log];
next->prev->next = next;
if (next->next != NULL)
next->next->prev = next;
}
/* Initialize the nfree and first counters for this block. */
block = BLOCK (result);
_heapinfo[block].busy.type = log;
_heapinfo[block].busy.info.frag.nfree = i - 1;
_heapinfo[block].busy.info.frag.first = i - 1;
_chunks_free += (BLOCKSIZE >> log) - 1;
_bytes_free += BLOCKSIZE - (1 << log);
_bytes_used -= BLOCKSIZE - (1 << log);
}
}
else
{
/* Large allocation to receive one or more blocks.
Search the free list in a circle starting at the last place visited.
If we loop completely around without finding a large enough
space we will have to get more memory from the system. */
blocks = BLOCKIFY (size);
start = block = MALLOC_SEARCH_START;
while (_heapinfo[block].free.size < blocks)
{
block = _heapinfo[block].free.next;
if (block == start)
{
/* Need to get more from the system. Check to see if
the new core will be contiguous with the final free
block; if so we don't need to get as much. */
block = _heapinfo[0].free.prev;
lastblocks = _heapinfo[block].free.size;
if (_heaplimit != 0 && block + lastblocks == _heaplimit &&
(*__morecore) (0) == ADDRESS (block + lastblocks) &&
(morecore ((blocks - lastblocks) * BLOCKSIZE)) != NULL)
{
_heapinfo[block].free.size = blocks;
_bytes_free += (blocks - lastblocks) * BLOCKSIZE;
continue;
}
result = morecore (blocks * BLOCKSIZE);
if (result == NULL)
return NULL;
block = BLOCK (result);
_heapinfo[block].busy.type = 0;
_heapinfo[block].busy.info.size = blocks;
++_chunks_used;
_bytes_used += blocks * BLOCKSIZE;
return result;
}
}
/* At this point we have found a suitable free list entry.
Figure out how to remove what we need from the list. */
result = ADDRESS (block);
if (_heapinfo[block].free.size > blocks)
{
/* The block we found has a bit left over,
so relink the tail end back into the free list. */
_heapinfo[block + blocks].free.size
= _heapinfo[block].free.size - blocks;
_heapinfo[block + blocks].free.next
= _heapinfo[block].free.next;
_heapinfo[block + blocks].free.prev
= _heapinfo[block].free.prev;
_heapinfo[_heapinfo[block].free.prev].free.next
= _heapinfo[_heapinfo[block].free.next].free.prev
= _heapindex = block + blocks;
}
else
{
/* The block exactly matches our requirements,
so just remove it from the list. */
_heapinfo[_heapinfo[block].free.next].free.prev
= _heapinfo[block].free.prev;
_heapinfo[_heapinfo[block].free.prev].free.next
= _heapindex = _heapinfo[block].free.next;
--_chunks_free;
}
_heapinfo[block].busy.type = 0;
_heapinfo[block].busy.info.size = blocks;
++_chunks_used;
_bytes_used += blocks * BLOCKSIZE;
_bytes_free -= blocks * BLOCKSIZE;
}
return result;
}
/* Free a block of memory allocated by `malloc'.
Copyright 1990, 1991, 1992 Free Software Foundation
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_INTERNAL
#define _MALLOC_INTERNAL
#include <malloc.h>
#endif
/* Debugging hook for free. */
void (*__free_hook) __P ((__ptr_t __ptr));
/* List of blocks allocated by memalign. */
struct alignlist *_aligned_blocks = NULL;
/* Return memory to the heap.
Like `free' but don't call a __free_hook if there is one. */
void
_free_internal (ptr)
__ptr_t ptr;
{
int type;
size_t block, blocks;
register size_t i;
struct list *prev, *next;
block = BLOCK (ptr);
type = _heapinfo[block].busy.type;
switch (type)
{
case 0:
/* Get as many statistics as early as we can. */
--_chunks_used;
_bytes_used -= _heapinfo[block].busy.info.size * BLOCKSIZE;
_bytes_free += _heapinfo[block].busy.info.size * BLOCKSIZE;
/* Find the free cluster previous to this one in the free list.
Start searching at the last block referenced; this may benefit
programs with locality of allocation. */
i = _heapindex;
if (i > block)
while (i > block)
i = _heapinfo[i].free.prev;
else
{
do
i = _heapinfo[i].free.next;
while (i > 0 && i < block);
i = _heapinfo[i].free.prev;
}
/* Determine how to link this block into the free list. */
if (block == i + _heapinfo[i].free.size)
{
/* Coalesce this block with its predecessor. */
_heapinfo[i].free.size += _heapinfo[block].busy.info.size;
block = i;
}
else
{
/* Really link this block back into the free list. */
_heapinfo[block].free.size = _heapinfo[block].busy.info.size;
_heapinfo[block].free.next = _heapinfo[i].free.next;
_heapinfo[block].free.prev = i;
_heapinfo[i].free.next = block;
_heapinfo[_heapinfo[block].free.next].free.prev = block;
++_chunks_free;
}
/* Now that the block is linked in, see if we can coalesce it
with its successor (by deleting its successor from the list
and adding in its size). */
if (block + _heapinfo[block].free.size == _heapinfo[block].free.next)
{
_heapinfo[block].free.size
+= _heapinfo[_heapinfo[block].free.next].free.size;
_heapinfo[block].free.next
= _heapinfo[_heapinfo[block].free.next].free.next;
_heapinfo[_heapinfo[block].free.next].free.prev = block;
--_chunks_free;
}
/* Now see if we can return stuff to the system. */
blocks = _heapinfo[block].free.size;
if (blocks >= FINAL_FREE_BLOCKS && block + blocks == _heaplimit
&& (*__morecore) (0) == ADDRESS (block + blocks))
{
register size_t bytes = blocks * BLOCKSIZE;
_heaplimit -= blocks;
(*__morecore) (-bytes);
_heapinfo[_heapinfo[block].free.prev].free.next
= _heapinfo[block].free.next;
_heapinfo[_heapinfo[block].free.next].free.prev
= _heapinfo[block].free.prev;
block = _heapinfo[block].free.prev;
--_chunks_free;
_bytes_free -= bytes;
}
/* Set the next search to begin at this block. */
_heapindex = block;
break;
default:
/* Do some of the statistics. */
--_chunks_used;
_bytes_used -= 1 << type;
++_chunks_free;
_bytes_free += 1 << type;
/* Get the address of the first free fragment in this block. */
prev = (struct list *) ((char *) ADDRESS (block) +
(_heapinfo[block].busy.info.frag.first << type));
if (_heapinfo[block].busy.info.frag.nfree == (BLOCKSIZE >> type) - 1)
{
/* If all fragments of this block are free, remove them
from the fragment list and free the whole block. */
next = prev;
for (i = 1; i < (size_t) (BLOCKSIZE >> type); ++i)
next = next->next;
prev->prev->next = next;
if (next != NULL)
next->prev = prev->prev;
_heapinfo[block].busy.type = 0;
_heapinfo[block].busy.info.size = 1;
/* Keep the statistics accurate. */
++_chunks_used;
_bytes_used += BLOCKSIZE;
_chunks_free -= BLOCKSIZE >> type;
_bytes_free -= BLOCKSIZE;
free (ADDRESS (block));
}
else if (_heapinfo[block].busy.info.frag.nfree != 0)
{
/* If some fragments of this block are free, link this
fragment into the fragment list after the first free
fragment of this block. */
next = (struct list *) ptr;
next->next = prev->next;
next->prev = prev;
prev->next = next;
if (next->next != NULL)
next->next->prev = next;
++_heapinfo[block].busy.info.frag.nfree;
}
else
{
/* No fragments of this block are free, so link this
fragment into the fragment list and announce that
it is the first free fragment of this block. */
prev = (struct list *) ptr;
_heapinfo[block].busy.info.frag.nfree = 1;
_heapinfo[block].busy.info.frag.first = (unsigned long int)
((unsigned long int) ((char *) ptr - (char *) NULL)
% BLOCKSIZE >> type);
prev->next = _fraghead[type].next;
prev->prev = &_fraghead[type];
prev->prev->next = prev;
if (prev->next != NULL)
prev->next->prev = prev;
}
break;
}
}
/* Return memory to the heap. */
void
free (ptr)
__ptr_t ptr;
{
register struct alignlist *l;
if (ptr == NULL)
return;
for (l = _aligned_blocks; l != NULL; l = l->next)
if (l->aligned == ptr)
{
l->aligned = NULL; /* Mark the slot in the list as free. */
ptr = l->exact;
break;
}
if (__free_hook != NULL)
(*__free_hook) (ptr);
else
_free_internal (ptr);
}
/* Change the size of a block allocated by `malloc'.
Copyright 1990, 1991, 1992 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_INTERNAL
#define _MALLOC_INTERNAL
#include <malloc.h>
#endif
#define min(A, B) ((A) < (B) ? (A) : (B))
/* Debugging hook for realloc. */
__ptr_t (*__realloc_hook) __P ((__ptr_t __ptr, size_t __size));
/* Resize the given region to the new size, returning a pointer
to the (possibly moved) region. This is optimized for speed;
some benchmarks seem to indicate that greater compactness is
achieved by unconditionally allocating and copying to a
new region. This module has incestuous knowledge of the
internals of both free and malloc. */
__ptr_t
realloc (ptr, size)
__ptr_t ptr;
size_t size;
{
__ptr_t result;
int type;
size_t block, blocks, oldlimit;
if (size == 0)
{
free (ptr);
return malloc (0);
}
else if (ptr == NULL)
return malloc (size);
if (__realloc_hook != NULL)
return (*__realloc_hook) (ptr, size);
block = BLOCK (ptr);
type = _heapinfo[block].busy.type;
switch (type)
{
case 0:
/* Maybe reallocate a large block to a small fragment. */
if (size <= BLOCKSIZE / 2)
{
result = malloc (size);
if (result != NULL)
{
memcpy (result, ptr, size);
free (ptr);
return result;
}
}
/* The new size is a large allocation as well;
see if we can hold it in place. */
blocks = BLOCKIFY (size);
if (blocks < _heapinfo[block].busy.info.size)
{
/* The new size is smaller; return
excess memory to the free list. */
_heapinfo[block + blocks].busy.type = 0;
_heapinfo[block + blocks].busy.info.size
= _heapinfo[block].busy.info.size - blocks;
_heapinfo[block].busy.info.size = blocks;
free (ADDRESS (block + blocks));
result = ptr;
}
else if (blocks == _heapinfo[block].busy.info.size)
/* No size change necessary. */
result = ptr;
else
{
/* Won't fit, so allocate a new region that will.
Free the old region first in case there is sufficient
adjacent free space to grow without moving. */
blocks = _heapinfo[block].busy.info.size;
/* Prevent free from actually returning memory to the system. */
oldlimit = _heaplimit;
_heaplimit = 0;
free (ptr);
_heaplimit = oldlimit;
result = malloc (size);
if (result == NULL)
{
(void) malloc (blocks * BLOCKSIZE);
return NULL;
}
if (ptr != result)
memmove (result, ptr, blocks * BLOCKSIZE);
}
break;
default:
/* Old size is a fragment; type is logarithm
to base two of the fragment size. */
if (size > (size_t) (1 << (type - 1)) && size <= (size_t) (1 << type))
/* The new size is the same kind of fragment. */
result = ptr;
else
{
/* The new size is different; allocate a new space,
and copy the lesser of the new size and the old. */
result = malloc (size);
if (result == NULL)
return NULL;
memcpy (result, ptr, min (size, (size_t) 1 << type));
free (ptr);
}
break;
}
return result;
}
/* Copyright (C) 1991, 1992 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
The GNU C 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with the GNU C Library; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
#ifndef _MALLOC_INTERNAL
#define _MALLOC_INTERNAL
#include <malloc.h>
#endif
#ifndef __GNU_LIBRARY__
#define __sbrk sbrk
#endif
extern __ptr_t __sbrk __P ((int increment));
#ifndef NULL
#define NULL 0
#endif
/* Allocate INCREMENT more bytes of data space,
and return the start of data space, or NULL on errors.
If INCREMENT is negative, shrink data space. */
__ptr_t
__default_morecore (increment)
ptrdiff_t increment;
{
__ptr_t result = __sbrk ((int) increment);
if (result == (__ptr_t) -1)
return NULL;
return result;
}
/* Copyright (C) 1991, 1992 Free Software Foundation, Inc.
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. */
#ifndef _MALLOC_INTERNAL
#define _MALLOC_INTERNAL
#include <malloc.h>
#endif
__ptr_t
memalign (alignment, size)
size_t alignment;
size_t size;
{
__ptr_t result;
unsigned long int adj;
size = ((size + alignment - 1) / alignment) * alignment;
result = malloc (size);
if (result == NULL)
return NULL;
adj = (unsigned long int) ((unsigned long int) ((char *) result -
(char *) NULL)) % alignment;
if (adj != 0)
{
struct alignlist *l;
for (l = _aligned_blocks; l != NULL; l = l->next)
if (l->aligned == NULL)
/* This slot is free. Use it. */
break;
if (l == NULL)
{
l = (struct alignlist *) malloc (sizeof (struct alignlist));
if (l == NULL)
{
free (result);
return NULL;
}
}
l->exact = result;
result = l->aligned = (char *) result + alignment - adj;
l->next = _aligned_blocks;
_aligned_blocks = l;
}
return result;
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.