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/* Minimal replacements for basic facilities used in the dynamic linker.
Copyright (C) 1995-1998,2000-2002,2004 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 Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
//#include <errno.h>
#include <limits.h>
#include <string.h>
#include <tls.h>
//#include <unistd.h>
#include <sys/param.h>
#include <sys/types.h>
#include <ldsodefs.h>
/* Minimal `malloc' allocator for use while loading shared libraries.
No block is ever freed. */
static void *alloc_ptr, *alloc_end, *alloc_last_block;
/* Declarations of global functions. */
extern void weak_function free (void *ptr);
extern void * weak_function realloc (void *ptr, size_t n);
/* Allocate an aligned memory block. */
void * weak_function
memalign (size_t align, size_t n)
{
#ifdef MAP_ANON
#define _dl_zerofd (-1)
#else
extern int _dl_zerofd;
if (_dl_zerofd == -1)
_dl_zerofd = _dl_sysdep_open_zero_fill ();
#define MAP_ANON 0
#endif
if (alloc_end == 0)
{
/* Consume any unused space in the last page of our data segment. */
extern int _end attribute_hidden;
alloc_ptr = &_end;
alloc_end = (void *) 0 + (((alloc_ptr - (void *) 0)
+ GLRO(dl_pagesize) - 1)
& ~(GLRO(dl_pagesize) - 1));
}
/* Make sure the allocation pointer is ideally aligned. */
alloc_ptr = (void *) 0 + (((alloc_ptr - (void *) 0) + align - 1)
& ~(align - 1));
if (alloc_ptr + n >= alloc_end)
{
/* Insufficient space left; allocate another page. */
caddr_t page;
size_t nup = (n + GLRO(dl_pagesize) - 1) & ~(GLRO(dl_pagesize) - 1);
page = _dl_mmap (0, nup, PROT_READ|PROT_WRITE,
MAP_ANON|MAP_PRIVATE, _dl_zerofd, 0);
if (_dl_mmap_check_error(page))
return -1;
if (page != alloc_end)
alloc_ptr = page;
alloc_end = page + nup;
}
alloc_last_block = (void *) alloc_ptr;
alloc_ptr += n;
return alloc_last_block;
}
void * weak_function
malloc (size_t n)
{
return memalign (sizeof (double), n);
}
/* We use this function occasionally since the real implementation may
be optimized when it can assume the memory it returns already is
set to NUL. */
void * weak_function
calloc (size_t nmemb, size_t size)
{
/* New memory from the trivial malloc above is always already cleared.
(We make sure that's true in the rare occasion it might not be,
by clearing memory in free, below.) */
return malloc (nmemb * size);
}
/* This will rarely be called. */
void weak_function
free (void *ptr)
{
/* We can free only the last block allocated. */
if (ptr == alloc_last_block)
{
/* Since this is rare, we clear the freed block here
so that calloc can presume malloc returns cleared memory. */
_dl_memset (alloc_last_block, '\0', alloc_ptr - alloc_last_block);
alloc_ptr = alloc_last_block;
}
}
/* This is only called with the most recent block returned by malloc. */
void * weak_function
realloc (void *ptr, size_t n)
{
void *new;
if (ptr == NULL)
return malloc (n);
assert (ptr == alloc_last_block);
alloc_ptr = alloc_last_block;
new = malloc (n);
assert (new == ptr);
return new;
}
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