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/* $OpenBSD: util.c,v 1.1 2002/02/21 23:17:53 drahn Exp $ */
#include <sys/types.h>
#include <sys/mman.h>
#include <string.h>
#include "archdep.h"
/*
* Static vars usable after bootsrapping.
*/
static void *_dl_malloc_base;
static void *_dl_malloc_pool = 0;
static long *_dl_malloc_free = 0;
char *
_dl_strdup(const char *orig)
{
char *newstr;
newstr = _dl_malloc(_dl_strlen(orig)+1);
_dl_strcpy(newstr, orig);
return (newstr);
}
/*
* The following malloc/free code is a very simplified implementation
* of a malloc function. However, we do not need to be very complex here
* because we only free memory when 'dlclose()' is called and we can
* reuse at least the memory allocated for the object descriptor. We have
* one dynamic string allocated, the library name and it is likely that
* we can reuse that one to without a lot of complex colapsing code.
*/
void *
_dl_malloc(int size)
{
long *p;
long *t, *n;
size = (size + 8 + DL_MALLOC_ALIGN - 1) & ~(DL_MALLOC_ALIGN - 1);
if ((t = _dl_malloc_free) != 0) { /* Try free list first */
n = (long *)&_dl_malloc_free;
while (t && t[-1] < size) {
n = t;
t = (long *)*t;
}
if (t) {
*n = *t;
_dl_memset(t, 0, t[-1] - 4);
return((void *)t);
}
}
if ((_dl_malloc_pool == 0) ||
(_dl_malloc_pool + size > _dl_malloc_base + 4096)) {
_dl_malloc_pool = (void *)_dl_mmap((void *)0, 4096,
PROT_READ|PROT_WRITE,
MAP_ANON|MAP_PRIVATE, -1, 0);
if (_dl_malloc_pool == 0 || _dl_malloc_pool == MAP_FAILED ) {
_dl_printf("Dynamic loader failure: malloc.\n");
_dl_exit(7);
}
_dl_malloc_base = _dl_malloc_pool;
}
p = _dl_malloc_pool;
_dl_malloc_pool += size;
_dl_memset(p, 0, size);
*p = size;
return((void *)(p + 1));
}
void
_dl_free(void *p)
{
long *t = (long *)p;
*t = (long)_dl_malloc_free;
_dl_malloc_free = p;
}
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