Differential D18988 Diff 53266 libexec/rtld-elf/malloc.c

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libexec/rtld-elf/malloc.c

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* The array of supported page sizes is provided by the user, i.e., the		* The array of supported page sizes is provided by the user, i.e., the
* program that calls this storage allocator. That program must initialize		* program that calls this storage allocator. That program must initialize
* the array before making its first call to allocate storage. The array		* the array before making its first call to allocate storage. The array
* must contain at least one page size. The page sizes must be stored in		* must contain at least one page size. The page sizes must be stored in
* increasing order.		* increasing order.
*/		*/

void *		void *
malloc(size_t nbytes)		__crt_malloc(size_t nbytes)
{		{
union overhead *op;		union overhead *op;
int bucket;		int bucket;
ssize_t n;		ssize_t n;
size_t amt;		size_t amt;

/*		/*
* First time malloc is called, setup page size and		* First time malloc is called, setup page size and
▲ Show 20 Lines • Show All 66 Lines • ▼ Show 20 Lines	#ifdef RCHECK
op->ov_size = roundup2(nbytes, RSLOP);		op->ov_size = roundup2(nbytes, RSLOP);
op->ov_rmagic = RMAGIC;		op->ov_rmagic = RMAGIC;
(u_short )((caddr_t)(op + 1) + op->ov_size) = RMAGIC;		(u_short )((caddr_t)(op + 1) + op->ov_size) = RMAGIC;
#endif		#endif
return ((char *)(op + 1));		return ((char *)(op + 1));
}		}

void *		void *
calloc(size_t num, size_t size)		__crt_calloc(size_t num, size_t size)
{		{
void *ret;		void *ret;

if (size != 0 && (num * size) / size != num) {		if (size != 0 && (num * size) / size != num) {
/* size_t overflow. */		/* size_t overflow. */
return (NULL);		return (NULL);
}		}

if ((ret = malloc(num * size)) != NULL)		if ((ret = __crt_malloc(num * size)) != NULL)
memset(ret, 0, num * size);		memset(ret, 0, num * size);

return (ret);		return (ret);
}		}

/*		/*
* Allocate more memory to the indicated bucket.		* Allocate more memory to the indicated bucket.
*/		*/
Show All 36 Lines	*/
nextf[bucket] = op;		nextf[bucket] = op;
while (--nblks > 0) {		while (--nblks > 0) {
op->ov_next = (union overhead *)((caddr_t)op + sz);		op->ov_next = (union overhead *)((caddr_t)op + sz);
op = (union overhead *)((caddr_t)op + sz);		op = (union overhead *)((caddr_t)op + sz);
}		}
}		}

void		void
free(void * cp)		__crt_free(void *cp)
{		{
int size;		int size;
union overhead *op;		union overhead *op;

if (cp == NULL)		if (cp == NULL)
return;		return;
op = (union overhead *)((caddr_t)cp - sizeof (union overhead));		op = (union overhead *)((caddr_t)cp - sizeof (union overhead));
#ifdef MALLOC_DEBUG		#ifdef MALLOC_DEBUG
Show All 24 Lines
* checking only the first block in each; if that fails we search		* checking only the first block in each; if that fails we search
* ``realloc_srchlen'' blocks in each list for a match (the variable		* ``realloc_srchlen'' blocks in each list for a match (the variable
* is extern so the caller can modify it). If that fails we just copy		* is extern so the caller can modify it). If that fails we just copy
* however many bytes was given to realloc() and hope it's not huge.		* however many bytes was given to realloc() and hope it's not huge.
*/		*/
static int realloc_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */		static int realloc_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */

void *		void *
realloc(void *cp, size_t nbytes)		__crt_realloc(void *cp, size_t nbytes)
{		{
u_int onb;		u_int onb;
int i;		int i;
union overhead *op;		union overhead *op;
char *res;		char *res;
int was_alloced = 0;		int was_alloced = 0;

if (cp == NULL)		if (cp == NULL)
return (malloc(nbytes));		return (__crt_malloc(nbytes));
op = (union overhead *)((caddr_t)cp - sizeof (union overhead));		op = (union overhead *)((caddr_t)cp - sizeof (union overhead));
if (op->ov_magic == MAGIC) {		if (op->ov_magic == MAGIC) {
was_alloced++;		was_alloced++;
i = op->ov_index;		i = op->ov_index;
} else {		} else {
/*		/*
* Already free, doing "compaction".		* Already free, doing "compaction".
*		*
Show All 28 Lines	if (was_alloced) {
}		}
if (nbytes <= onb && nbytes > (size_t)i) {		if (nbytes <= onb && nbytes > (size_t)i) {
#ifdef RCHECK		#ifdef RCHECK
op->ov_size = roundup2(nbytes, RSLOP);		op->ov_size = roundup2(nbytes, RSLOP);
(u_short )((caddr_t)(op + 1) + op->ov_size) = RMAGIC;		(u_short )((caddr_t)(op + 1) + op->ov_size) = RMAGIC;
#endif		#endif
return(cp);		return(cp);
} else		} else
free(cp);		__crt_free(cp);
}		}
if ((res = malloc(nbytes)) == NULL)		if ((res = __crt_malloc(nbytes)) == NULL)
return (NULL);		return (NULL);
if (cp != res) /* common optimization if "compacting" */		if (cp != res) /* common optimization if "compacting" */
bcopy(cp, res, (nbytes < onb) ? nbytes : onb);		bcopy(cp, res, (nbytes < onb) ? nbytes : onb);
return (res);		return (res);
}		}

/*		/*
* Search ``srchlen'' elements of each free list for a block whose		* Search ``srchlen'' elements of each free list for a block whose
▲ Show 20 Lines • Show All 55 Lines • ▼ Show 20 Lines
{		{
int fd = -1;		int fd = -1;
int offset;		int offset;

if (pagepool_end - pagepool_start > pagesz) {		if (pagepool_end - pagepool_start > pagesz) {
caddr_t addr = (caddr_t)		caddr_t addr = (caddr_t)
(((long)pagepool_start + pagesz - 1) & ~(pagesz - 1));		(((long)pagepool_start + pagesz - 1) & ~(pagesz - 1));
if (munmap(addr, pagepool_end - addr) != 0) {		if (munmap(addr, pagepool_end - addr) != 0) {
		#ifdef IN_RTLD
rtld_fdprintf(STDERR_FILENO, _BASENAME_RTLD ": "		rtld_fdprintf(STDERR_FILENO, _BASENAME_RTLD ": "
"morepages: cannot munmap %p: %s\n",		"morepages: cannot munmap %p: %s\n",
addr, rtld_strerror(errno));		addr, rtld_strerror(errno));
		#endif
}		}
}		}

offset = (long)pagepool_start - ((long)pagepool_start & ~(pagesz - 1));		offset = (long)pagepool_start - ((long)pagepool_start & ~(pagesz - 1));

if ((pagepool_start = mmap(0, n * pagesz,		if ((pagepool_start = mmap(0, n * pagesz,
PROT_READ\|PROT_WRITE,		PROT_READ\|PROT_WRITE,
MAP_ANON\|MAP_PRIVATE, fd, 0)) == (caddr_t)-1) {		MAP_ANON\|MAP_PRIVATE, fd, 0)) == (caddr_t)-1) {
		#ifdef IN_RTLD
rtld_fdprintf(STDERR_FILENO, _BASENAME_RTLD ": morepages: "		rtld_fdprintf(STDERR_FILENO, _BASENAME_RTLD ": morepages: "
"cannot mmap anonymous memory: %s\n",		"cannot mmap anonymous memory: %s\n",
rtld_strerror(errno));		rtld_strerror(errno));
		#endif
return 0;		return 0;
}		}
pagepool_end = pagepool_start + n * pagesz;		pagepool_end = pagepool_start + n * pagesz;
pagepool_start += offset;		pagepool_start += offset;

return n;		return n;
}		}