981 lines
25 KiB
C
981 lines
25 KiB
C
/* malloc.c - dynamic memory allocation for bash. */
|
|
|
|
/* Copyright (C) 1985, 1987, 1997 Free Software Foundation, Inc.
|
|
|
|
This program 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.
|
|
|
|
This program 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 this program; if not, write to the Free Software
|
|
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111 USA.
|
|
|
|
In other words, you are welcome to use, share and improve this program.
|
|
You are forbidden to forbid anyone else to use, share and improve
|
|
what you give them. Help stamp out software-hoarding! */
|
|
|
|
/*
|
|
* @(#)nmalloc.c 1 (Caltech) 2/21/82
|
|
*
|
|
* U of M Modified: 20 Jun 1983 ACT: strange hacks for Emacs
|
|
*
|
|
* Nov 1983, Mike@BRL, Added support for 4.1C/4.2 BSD.
|
|
*
|
|
* This is a very fast storage allocator. It allocates blocks of a small
|
|
* number of different sizes, and keeps free lists of each size. Blocks
|
|
* that don't exactly fit are passed up to the next larger size. In this
|
|
* implementation, the available sizes are (2^n)-4 (or -16) bytes long.
|
|
* This is designed for use in a program that uses vast quantities of
|
|
* memory, but bombs when it runs out. To make it a little better, it
|
|
* warns the user when he starts to get near the end.
|
|
*
|
|
* June 84, ACT: modified rcheck code to check the range given to malloc,
|
|
* rather than the range determined by the 2-power used.
|
|
*
|
|
* Jan 85, RMS: calls malloc_warning to issue warning on nearly full.
|
|
* No longer Emacs-specific; can serve as all-purpose malloc for GNU.
|
|
* You should call malloc_init to reinitialize after loading dumped Emacs.
|
|
* Call malloc_stats to get info on memory stats if MALLOC_STATS turned on.
|
|
* realloc knows how to return same block given, just changing its size,
|
|
* if the power of 2 is correct.
|
|
*/
|
|
#define MALLOC_STATS /* for the time being */
|
|
|
|
/*
|
|
* nextf[i] is the pointer to the next free block of size 2^(i+3). The
|
|
* smallest allocatable block is 8 bytes. The overhead information will
|
|
* go in the first int of the block, and the returned pointer will point
|
|
* to the second.
|
|
*/
|
|
|
|
/* Define this to have free() write 0xcf into memory as it's freed, to
|
|
uncover callers that refer to freed memory. */
|
|
/* SCO 3.2v4 getcwd and possibly other libc routines fail with MEMSCRAMBLE */
|
|
#if !defined (NO_MEMSCRAMBLE)
|
|
# define MEMSCRAMBLE
|
|
#endif
|
|
|
|
#if defined (HAVE_CONFIG_H)
|
|
# include <config.h>
|
|
#endif /* HAVE_CONFIG_H */
|
|
|
|
#if defined (SHELL)
|
|
# include "bashtypes.h"
|
|
#else
|
|
# include <sys/types.h>
|
|
#endif
|
|
|
|
#if defined (HAVE_UNISTD_H)
|
|
# include <unistd.h>
|
|
#endif
|
|
|
|
/* Determine which kind of system this is. */
|
|
#include <signal.h>
|
|
|
|
#if defined (HAVE_STRING_H)
|
|
# include <string.h>
|
|
#else
|
|
# include <strings.h>
|
|
#endif
|
|
|
|
#if defined (MALLOC_STATS) || !defined (botch)
|
|
# include <stdio.h>
|
|
#endif /* MALLOC_STATS || !botch */
|
|
|
|
/* Define getpagesize () if the system does not. */
|
|
#ifndef HAVE_GETPAGESIZE
|
|
# include "getpagesize.h"
|
|
#endif
|
|
|
|
#if __GNUC__ > 1
|
|
# define FASTCOPY(s, d, n) __builtin_memcpy (d, s, n)
|
|
#else /* !__GNUC__ */
|
|
# if !defined (HAVE_BCOPY)
|
|
# if !defined (HAVE_MEMMOVE)
|
|
# define FASTCOPY(s, d, n) memcpy (d, s, n)
|
|
# else
|
|
# define FASTCOPY(s, d, n) memmove (d, s, n)
|
|
# endif /* !HAVE_MEMMOVE */
|
|
# else /* HAVE_BCOPY */
|
|
# define FASTCOPY(s, d, n) bcopy (s, d, n)
|
|
# endif /* HAVE_BCOPY */
|
|
#endif /* !__GNUC__ */
|
|
|
|
/* Generic pointer type. */
|
|
#ifndef PTR_T
|
|
# if defined (__STDC__)
|
|
# define PTR_T void *
|
|
# else
|
|
# define PTR_T char *
|
|
# endif
|
|
#endif
|
|
|
|
#if !defined (NULL)
|
|
# define NULL 0
|
|
#endif
|
|
|
|
#define NBUCKETS 30
|
|
|
|
#define ISALLOC ((char) 0xf7) /* magic byte that implies allocation */
|
|
#define ISFREE ((char) 0x54) /* magic byte that implies free block */
|
|
/* this is for error checking only */
|
|
#define ISMEMALIGN ((char) 0xd6) /* Stored before the value returned by
|
|
memalign, with the rest of the word
|
|
being the distance to the true
|
|
beginning of the block. */
|
|
|
|
#if !defined (SBRK_DECLARED)
|
|
extern char *sbrk ();
|
|
#endif /* !SBRK_DECLARED */
|
|
|
|
#ifdef MALLOC_STATS
|
|
/*
|
|
* NMALLOC[i] is the difference between the number of mallocs and frees
|
|
* for a given block size. TMALLOC[i] is the total number of mallocs for
|
|
* a given block size. NMORECORE[i] is the total number of calls to
|
|
* morecore(i). NMAL and NFRE are counts of the number of calls to malloc()
|
|
* and free(), respectively. NREALLOC is the total number of calls to
|
|
* realloc(); NRCOPY is the number of times realloc() had to allocate new
|
|
* memory and copy to it. NRECURSE is a count of the number of recursive
|
|
* calls to malloc() for the same bucket size, which can be caused by calls
|
|
* to malloc() from a signal handler. NSBRK is the number of calls to sbrk()
|
|
* (whether by morecore() or for alignment); TSBRK is the total number of
|
|
* bytes requested from the kernel with sbrk(). BYTESUSED is the total
|
|
* number of bytes consumed by blocks currently in use; BYTESFREE is the
|
|
* total number of bytes currently on all of the free lists. TBSPLIT is
|
|
* the number of times a larger block was split to satisfy a smaller request.
|
|
* NSPLIT[i] is the number of times a block of size I was split.
|
|
* TBCOALESCE is the number of times two adjacent smaller blocks off the free
|
|
* list were combined to satisfy a larger request.
|
|
*/
|
|
struct _malstats {
|
|
int nmalloc[NBUCKETS];
|
|
int tmalloc[NBUCKETS];
|
|
int nmorecore[NBUCKETS];
|
|
int nmal;
|
|
int nfre;
|
|
int nrealloc;
|
|
int nrcopy;
|
|
int nrecurse;
|
|
int nsbrk;
|
|
bits32_t tsbrk;
|
|
bits32_t bytesused;
|
|
bits32_t bytesfree;
|
|
int tbsplit;
|
|
int nsplit[NBUCKETS];
|
|
int tbcoalesce;
|
|
};
|
|
|
|
static struct _malstats _mstats;
|
|
|
|
/* Return statistics describing allocation of blocks of size BLOCKSIZE.
|
|
NFREE is the number of free blocks for this allocation size. NUSED
|
|
is the number of blocks in use. NMAL is the number of requests for
|
|
blocks of size BLOCKSIZE. NMORECORE is the number of times we had
|
|
to call MORECORE to repopulate the free list for this bucket. NSPLIT
|
|
is the number of times a block of this size was split to satisfy a
|
|
smaller request. */
|
|
struct bucket_stats {
|
|
u_bits32_t blocksize;
|
|
int nfree;
|
|
int nused;
|
|
int nmal;
|
|
int nmorecore;
|
|
int nsplit;
|
|
};
|
|
#endif /* MALLOC_STATS */
|
|
|
|
/* We have a flag indicating whether memory is allocated, an index in
|
|
nextf[], a size field, and a sentinel value to determine whether or
|
|
not a caller wrote before the start of allocated memory; to realloc()
|
|
memory we either copy mh_nbytes or just change mh_nbytes if there is
|
|
enough room in the block for the new size. Range checking is always
|
|
done. */
|
|
union mhead {
|
|
bits64_t mh_align; /* 8 */
|
|
struct {
|
|
char mi_alloc; /* ISALLOC or ISFREE */ /* 1 */
|
|
char mi_index; /* index in nextf[] */ /* 1 */
|
|
/* Remainder are valid only when block is allocated */
|
|
u_bits32_t mi_nbytes; /* # of bytes allocated */ /* 4 */
|
|
u_bits16_t mi_magic2;/* should be == MAGIC2 */ /* 2 */
|
|
} minfo;
|
|
};
|
|
#define mh_alloc minfo.mi_alloc
|
|
#define mh_index minfo.mi_index
|
|
#define mh_nbytes minfo.mi_nbytes
|
|
#define mh_magic2 minfo.mi_magic2
|
|
|
|
/* Access free-list pointer of a block.
|
|
It is stored at block + sizeof (char *).
|
|
This is not a field in the minfo structure member of union mhead
|
|
because we want sizeof (union mhead)
|
|
to describe the overhead for when the block is in use,
|
|
and we do not want the free-list pointer to count in that. */
|
|
|
|
#define CHAIN(a) \
|
|
(*(union mhead **) (sizeof (char *) + (char *) (a)))
|
|
|
|
#if defined (botch)
|
|
extern void botch ();
|
|
#else
|
|
static void
|
|
botch (s)
|
|
char *s;
|
|
{
|
|
fprintf (stderr, "\r\nmalloc: assertion botched: %s\r\n", s);
|
|
(void)fflush (stderr);
|
|
abort ();
|
|
}
|
|
#endif /* !botch */
|
|
|
|
#if !defined (__STRING)
|
|
# if defined (__STDC__)
|
|
# define __STRING(x) #x
|
|
# else
|
|
# define __STRING(x) "x"
|
|
# endif
|
|
#endif /* !__STRING */
|
|
|
|
/* To implement range checking, we write magic values in at the beginning
|
|
and end of each allocated block, and make sure they are undisturbed
|
|
whenever a free or a realloc occurs. */
|
|
|
|
/* Written in each of the 4 bytes following the block's real space */
|
|
#define MAGIC1 0x55
|
|
/* Written in the 2 bytes before the block's real space */
|
|
#define MAGIC2 0x5555
|
|
#define ASSERT(p) do { if (!(p)) botch(__STRING(p)); } while (0)
|
|
#define MSLOP 4 /* 4 bytes extra for MAGIC1s */
|
|
|
|
/* Minimum and maximum bucket indices for block splitting (and to bound
|
|
the search for a block to split). */
|
|
#define SPLIT_MIN 3
|
|
#define SPLIT_MID 11 /* XXX - was 9 */
|
|
#define SPLIT_MAX 14 /* XXX - was 12 */
|
|
|
|
/* Minimum and maximum bucket indices for block coalescing. */
|
|
#define COMBINE_MIN 6
|
|
#define COMBINE_MAX (pagebucket - 1)
|
|
|
|
#define MIN_COMBINE_FREE 4
|
|
|
|
/* nextf[i] is free list of blocks of size 2**(i + 3) */
|
|
|
|
static union mhead *nextf[NBUCKETS];
|
|
|
|
/* busy[i] is nonzero while allocation of block size i is in progress. */
|
|
|
|
static char busy[NBUCKETS];
|
|
|
|
static int pagesz; /* system page size. */
|
|
static int pagebucket; /* bucket for requests a page in size */
|
|
static int maxbuck; /* highest bucket receiving allocation request. */
|
|
|
|
#ifdef SHELL
|
|
extern int interrupt_immediately;
|
|
extern int signal_is_trapped ();
|
|
#endif
|
|
|
|
#if 0
|
|
/* Coalesce two adjacent free blocks off the free list for size NU - 1,
|
|
as long as there are at least MIN_COMBINE_FREE free blocks and we
|
|
can find two adjacent free blocks. nextf[NU -1] is assumed to not
|
|
be busy; the caller (morecore()) checks for this. */
|
|
static void
|
|
bcoalesce (nu)
|
|
register int nu;
|
|
{
|
|
register union mhead *mp, *mp1, *mp2;
|
|
register int nfree, nbuck;
|
|
unsigned long siz;
|
|
|
|
nbuck = nu - 1;
|
|
if (nextf[nbuck] == 0)
|
|
return;
|
|
|
|
nfree = 1;
|
|
mp1 = nextf[nbuck];
|
|
mp = CHAIN (mp1);
|
|
mp2 = (union mhead *)0;
|
|
while (CHAIN (mp))
|
|
{
|
|
mp2 = mp1;
|
|
mp1 = mp;
|
|
mp = CHAIN (mp);
|
|
nfree++;
|
|
/* We may not want to run all the way through the free list here;
|
|
if we do not, we need to check a threshold value here and break
|
|
if nfree exceeds it. */
|
|
}
|
|
if (nfree < MIN_COMBINE_FREE)
|
|
return;
|
|
/* OK, now we have mp1 pointing to the block we want to add to nextf[NU].
|
|
CHAIN(mp2) must equal mp1. Check that mp1 and mp are adjacent. */
|
|
if (CHAIN(mp2) != mp1)
|
|
botch ("bcoalesce: CHAIN(mp2) != mp1");
|
|
siz = 1 << (nbuck + 3);
|
|
if (CHAIN (mp1) != (union mhead *)((char *)mp1 + siz))
|
|
return; /* not adjacent */
|
|
|
|
#ifdef MALLOC_STATS
|
|
_mstats.tbcoalesce++;
|
|
#endif
|
|
|
|
/* Since they are adjacent, remove them from the free list */
|
|
CHAIN (mp2) = CHAIN (mp);
|
|
|
|
/* And add the combined two blocks to nextf[NU]. */
|
|
mp1->mh_alloc = ISFREE;
|
|
mp1->mh_index = nu;
|
|
CHAIN (mp1) = nextf[nu];
|
|
nextf[nu] = mp1;
|
|
}
|
|
#endif
|
|
|
|
/* Split a block at index > NU (but less than SPLIT_MAX) into a set of
|
|
blocks of the correct size, and attach them to nextf[NU]. nextf[NU]
|
|
is assumed to be empty. Must be called with signals blocked (e.g.,
|
|
by morecore()). */
|
|
static void
|
|
bsplit (nu)
|
|
register int nu;
|
|
{
|
|
register union mhead *mp;
|
|
int nbuck, nblks, split_max;
|
|
unsigned long siz;
|
|
|
|
split_max = (maxbuck > SPLIT_MAX) ? maxbuck : SPLIT_MAX;
|
|
|
|
if (nu >= SPLIT_MID)
|
|
{
|
|
for (nbuck = split_max; nbuck > nu; nbuck--)
|
|
{
|
|
if (busy[nbuck] || nextf[nbuck] == 0)
|
|
continue;
|
|
break;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
for (nbuck = nu + 1; nbuck <= split_max; nbuck++)
|
|
{
|
|
if (busy[nbuck] || nextf[nbuck] == 0)
|
|
continue;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (nbuck > split_max || nbuck <= nu)
|
|
return;
|
|
|
|
/* XXX might want to split only if nextf[nbuck] has >= 2 blocks free
|
|
and nbuck is below some threshold. */
|
|
|
|
#ifdef MALLOC_STATS
|
|
_mstats.tbsplit++;
|
|
_mstats.nsplit[nbuck]++;
|
|
#endif
|
|
|
|
/* Figure out how many blocks we'll get. */
|
|
siz = (1 << (nu + 3));
|
|
nblks = (1 << (nbuck + 3)) / siz;
|
|
|
|
/* Remove the block from the chain of larger blocks. */
|
|
mp = nextf[nbuck];
|
|
nextf[nbuck] = CHAIN (mp);
|
|
|
|
/* Split the block and put it on the requested chain. */
|
|
nextf[nu] = mp;
|
|
while (1)
|
|
{
|
|
mp->mh_alloc = ISFREE;
|
|
mp->mh_index = nu;
|
|
if (--nblks <= 0) break;
|
|
CHAIN (mp) = (union mhead *)((char *)mp + siz);
|
|
mp = (union mhead *)((char *)mp + siz);
|
|
}
|
|
CHAIN (mp) = 0;
|
|
}
|
|
|
|
static void
|
|
block_signals (setp, osetp)
|
|
sigset_t *setp, *osetp;
|
|
{
|
|
#ifdef HAVE_POSIX_SIGNALS
|
|
sigfillset (setp);
|
|
sigemptyset (osetp);
|
|
sigprocmask (SIG_BLOCK, setp, osetp);
|
|
#else
|
|
# if defined (HAVE_BSD_SIGNALS)
|
|
*osetp = sigsetmask (-1);
|
|
# endif
|
|
#endif
|
|
}
|
|
|
|
static void
|
|
unblock_signals (setp, osetp)
|
|
sigset_t *setp, *osetp;
|
|
{
|
|
#ifdef HAVE_POSIX_SIGNALS
|
|
sigprocmask (SIG_SETMASK, osetp, (sigset_t *)NULL);
|
|
#else
|
|
# if defined (HAVE_BSD_SIGNALS)
|
|
sigsetmask (*osetp);
|
|
# endif
|
|
#endif
|
|
}
|
|
|
|
static void
|
|
morecore (nu) /* ask system for more memory */
|
|
register int nu; /* size index to get more of */
|
|
{
|
|
register union mhead *mp;
|
|
register int nblks;
|
|
register long siz;
|
|
long sbrk_amt; /* amount to get via sbrk() */
|
|
sigset_t set, oset;
|
|
int blocked_sigs;
|
|
|
|
/* Block all signals in case we are executed from a signal handler. */
|
|
blocked_sigs = 0;
|
|
#ifdef SHELL
|
|
if (interrupt_immediately || signal_is_trapped (SIGINT) || signal_is_trapped (SIGCHLD))
|
|
#endif
|
|
{
|
|
block_signals (&set, &oset);
|
|
blocked_sigs = 1;
|
|
}
|
|
|
|
siz = 1 << (nu + 3); /* size of desired block for nextf[nu] */
|
|
|
|
if (siz < 0)
|
|
goto morecore_done; /* oops */
|
|
|
|
#ifdef MALLOC_STATS
|
|
_mstats.nmorecore[nu]++;
|
|
#endif
|
|
|
|
/* Try to split a larger block here, if we're within the range of sizes
|
|
to split. */
|
|
#if 0
|
|
if (nu >= SPLIT_MIN && nu < SPLIT_MAX)
|
|
#else
|
|
if (nu >= SPLIT_MIN)
|
|
#endif
|
|
{
|
|
bsplit (nu);
|
|
if (nextf[nu] != 0)
|
|
goto morecore_done;
|
|
}
|
|
|
|
#if 0
|
|
/* Try to coalesce two adjacent blocks from the free list on nextf[nu - 1],
|
|
if we can, and we're withing the range of the block coalescing limits. */
|
|
if (nu >= COMBINE_MIN && nu < COMBINE_MAX && busy[nu - 1] == 0 && nextf[nu - 1])
|
|
{
|
|
bcoalesce (nu);
|
|
if (nextf[nu] != 0)
|
|
goto morecore_done;
|
|
}
|
|
#endif
|
|
|
|
/* Take at least a page, and figure out how many blocks of the requested
|
|
size we're getting. */
|
|
if (siz <= pagesz)
|
|
{
|
|
sbrk_amt = pagesz;
|
|
nblks = sbrk_amt / siz;
|
|
}
|
|
else
|
|
{
|
|
/* We always want to request an integral multiple of the page size
|
|
from the kernel, so let's compute whether or not `siz' is such
|
|
an amount. If it is, we can just request it. If not, we want
|
|
the smallest integral multiple of pagesize that is larger than
|
|
`siz' and will satisfy the request. */
|
|
sbrk_amt = siz % pagesz;
|
|
if (sbrk_amt == 0)
|
|
sbrk_amt = siz;
|
|
else
|
|
sbrk_amt = siz + pagesz - sbrk_amt;
|
|
nblks = 1;
|
|
}
|
|
|
|
#ifdef MALLOC_STATS
|
|
_mstats.nsbrk++;
|
|
_mstats.tsbrk += sbrk_amt;
|
|
#endif
|
|
|
|
mp = (union mhead *) sbrk (sbrk_amt);
|
|
|
|
/* Totally out of memory. */
|
|
if ((long)mp == -1)
|
|
goto morecore_done;
|
|
|
|
/* shouldn't happen, but just in case -- require 8-byte alignment */
|
|
if ((long)mp & 7)
|
|
{
|
|
mp = (union mhead *) (((long)mp + 8) & ~7);
|
|
nblks--;
|
|
}
|
|
|
|
/* save new header and link the nblks blocks together */
|
|
nextf[nu] = mp;
|
|
while (1)
|
|
{
|
|
mp->mh_alloc = ISFREE;
|
|
mp->mh_index = nu;
|
|
if (--nblks <= 0) break;
|
|
CHAIN (mp) = (union mhead *)((char *)mp + siz);
|
|
mp = (union mhead *)((char *)mp + siz);
|
|
}
|
|
CHAIN (mp) = 0;
|
|
|
|
morecore_done:
|
|
if (blocked_sigs)
|
|
unblock_signals (&set, &oset);
|
|
}
|
|
|
|
#if defined (MEMSCRAMBLE) || !defined (NO_CALLOC)
|
|
static char *
|
|
zmemset (s, c, n)
|
|
char *s;
|
|
int c;
|
|
register int n;
|
|
{
|
|
register char *sp;
|
|
|
|
sp = s;
|
|
while (--n >= 0)
|
|
*sp++ = c;
|
|
return (s);
|
|
}
|
|
#endif /* MEMSCRAMBLE || !NO_CALLOC */
|
|
|
|
static void
|
|
malloc_debug_dummy ()
|
|
{
|
|
write (1, "malloc_debug_dummy\n", 19);
|
|
}
|
|
|
|
PTR_T
|
|
malloc (n) /* get a block */
|
|
size_t n;
|
|
{
|
|
register union mhead *p;
|
|
register long nbytes;
|
|
register int nunits;
|
|
|
|
/* Get the system page size and align break pointer so everything will
|
|
be page-aligned. The page size must be at least 1K -- anything
|
|
smaller is increased. */
|
|
if (pagesz == 0)
|
|
{
|
|
register long sbrk_needed;
|
|
|
|
pagesz = getpagesize ();
|
|
if (pagesz < 1024)
|
|
pagesz = 1024;
|
|
/* OK, how much do we need to allocate to make things page-aligned?
|
|
This partial page is wasted space. Once we figure out how much
|
|
to advance the break pointer, go ahead and do it. */
|
|
sbrk_needed = pagesz - ((long)sbrk (0) & (pagesz - 1)); /* sbrk(0) % pagesz */
|
|
if (sbrk_needed < 0)
|
|
sbrk_needed += pagesz;
|
|
/* Now allocate the wasted space. */
|
|
if (sbrk_needed)
|
|
{
|
|
#ifdef MALLOC_STATS
|
|
_mstats.nsbrk++;
|
|
_mstats.tsbrk += sbrk_needed;
|
|
#endif
|
|
if ((long)sbrk (sbrk_needed) == -1)
|
|
return (NULL);
|
|
}
|
|
nunits = 0;
|
|
nbytes = 8;
|
|
while (pagesz > nbytes)
|
|
{
|
|
nbytes <<= 1;
|
|
nunits++;
|
|
}
|
|
pagebucket = nunits;
|
|
}
|
|
|
|
/* Figure out how many bytes are required, rounding up to the nearest
|
|
multiple of 4, then figure out which nextf[] area to use. Try to
|
|
be smart about where to start searching -- if the number of bytes
|
|
needed is greater than the page size, we can start at pagebucket. */
|
|
nbytes = (n + sizeof *p + MSLOP + 3) & ~3;
|
|
nunits = 0;
|
|
if (nbytes <= (pagesz >> 1))
|
|
{
|
|
register unsigned int shiftr;
|
|
|
|
shiftr = (nbytes - 1) >> 2; /* == (nbytes - 1) / 4 */
|
|
while (shiftr >>= 1) /* == (nbytes - 1) / {8,16,32,...} */
|
|
nunits++;
|
|
}
|
|
else
|
|
{
|
|
register u_bits32_t amt;
|
|
|
|
nunits = pagebucket;
|
|
amt = pagesz;
|
|
while (nbytes > amt)
|
|
{
|
|
amt <<= 1;
|
|
nunits++;
|
|
}
|
|
}
|
|
|
|
/* In case this is reentrant use of malloc from signal handler,
|
|
pick a block size that no other malloc level is currently
|
|
trying to allocate. That's the easiest harmless way not to
|
|
interfere with the other level of execution. */
|
|
#ifdef MALLOC_STATS
|
|
if (busy[nunits]) _mstats.nrecurse++;
|
|
#endif
|
|
while (busy[nunits]) nunits++;
|
|
busy[nunits] = 1;
|
|
|
|
if (nunits > maxbuck)
|
|
maxbuck = nunits;
|
|
|
|
/* If there are no blocks of the appropriate size, go get some */
|
|
if (nextf[nunits] == 0)
|
|
morecore (nunits);
|
|
|
|
/* Get one block off the list, and set the new list head */
|
|
if ((p = nextf[nunits]) == NULL)
|
|
{
|
|
busy[nunits] = 0;
|
|
return NULL;
|
|
}
|
|
nextf[nunits] = CHAIN (p);
|
|
busy[nunits] = 0;
|
|
|
|
/* Check for free block clobbered */
|
|
/* If not for this check, we would gobble a clobbered free chain ptr
|
|
and bomb out on the NEXT allocate of this size block */
|
|
if (p->mh_alloc != ISFREE || p->mh_index != nunits)
|
|
botch ("malloc: block on free list clobbered");
|
|
|
|
/* Fill in the info, and if range checking, set up the magic numbers */
|
|
p->mh_alloc = ISALLOC;
|
|
p->mh_nbytes = n;
|
|
p->mh_magic2 = MAGIC2;
|
|
{
|
|
register char *m = (char *) (p + 1) + n;
|
|
|
|
*m++ = MAGIC1, *m++ = MAGIC1, *m++ = MAGIC1, *m = MAGIC1;
|
|
}
|
|
|
|
#ifdef MEMSCRAMBLE
|
|
zmemset ((char *)(p + 1), 0xdf, n); /* scramble previous contents */
|
|
#endif
|
|
#ifdef MALLOC_STATS
|
|
_mstats.nmalloc[nunits]++;
|
|
_mstats.tmalloc[nunits]++;
|
|
_mstats.nmal++;
|
|
#endif /* MALLOC_STATS */
|
|
return (char *) (p + 1); /* XXX - should be cast to PTR_T? */
|
|
}
|
|
|
|
void
|
|
free (mem)
|
|
PTR_T mem;
|
|
{
|
|
register union mhead *p;
|
|
register char *ap;
|
|
register int nunits;
|
|
|
|
if ((ap = (char *)mem) == 0)
|
|
return;
|
|
|
|
p = (union mhead *) ap - 1;
|
|
|
|
if (p->mh_alloc == ISMEMALIGN)
|
|
{
|
|
ap -= p->mh_nbytes;
|
|
p = (union mhead *) ap - 1;
|
|
}
|
|
|
|
if (p->mh_alloc != ISALLOC)
|
|
{
|
|
if (p->mh_alloc == ISFREE)
|
|
botch ("free: called with already freed block argument");
|
|
else
|
|
botch ("free: called with unallocated block argument");
|
|
}
|
|
|
|
ASSERT (p->mh_magic2 == MAGIC2);
|
|
ap += p->mh_nbytes;
|
|
ASSERT (*ap++ == MAGIC1); ASSERT (*ap++ == MAGIC1);
|
|
ASSERT (*ap++ == MAGIC1); ASSERT (*ap == MAGIC1);
|
|
|
|
#ifdef MEMSCRAMBLE
|
|
zmemset (mem, 0xcf, p->mh_nbytes);
|
|
#endif
|
|
|
|
nunits = p->mh_index;
|
|
|
|
ASSERT (nunits < NBUCKETS);
|
|
p->mh_alloc = ISFREE;
|
|
|
|
#if 0
|
|
if (busy[nunits] == 1)
|
|
botch ("calling free %d while in malloc for %d", nunits, nunits);
|
|
#endif
|
|
|
|
/* Protect against signal handlers calling malloc. */
|
|
busy[nunits] = 1;
|
|
/* Put this block on the free list. */
|
|
CHAIN (p) = nextf[nunits];
|
|
nextf[nunits] = p;
|
|
busy[nunits] = 0;
|
|
|
|
#ifdef MALLOC_STATS
|
|
_mstats.nmalloc[nunits]--;
|
|
_mstats.nfre++;
|
|
#endif /* MALLOC_STATS */
|
|
}
|
|
|
|
PTR_T
|
|
realloc (mem, n)
|
|
PTR_T mem;
|
|
register size_t n;
|
|
{
|
|
register union mhead *p;
|
|
register u_bits32_t tocopy;
|
|
register unsigned int nbytes;
|
|
register int nunits;
|
|
register char *m;
|
|
|
|
#ifdef MALLOC_STATS
|
|
_mstats.nrealloc++;
|
|
#endif
|
|
|
|
if (n == 0)
|
|
{
|
|
free (mem);
|
|
return (NULL);
|
|
}
|
|
if ((p = (union mhead *) mem) == 0)
|
|
return malloc (n);
|
|
p--;
|
|
nunits = p->mh_index;
|
|
ASSERT (p->mh_alloc == ISALLOC);
|
|
ASSERT (p->mh_magic2 == MAGIC2);
|
|
|
|
m = (char *)mem + (tocopy = p->mh_nbytes);
|
|
ASSERT (*m++ == MAGIC1); ASSERT (*m++ == MAGIC1);
|
|
ASSERT (*m++ == MAGIC1); ASSERT (*m == MAGIC1);
|
|
|
|
/* See if desired size rounds to same power of 2 as actual size. */
|
|
nbytes = (n + sizeof *p + MSLOP + 7) & ~7;
|
|
|
|
/* If ok, use the same block, just marking its size as changed. */
|
|
if (nbytes > (4 << nunits) && nbytes <= (8 << nunits))
|
|
{
|
|
m = (char *)mem + tocopy;
|
|
*m++ = 0; *m++ = 0; *m++ = 0; *m++ = 0;
|
|
p->mh_nbytes = n;
|
|
m = (char *)mem + n;
|
|
*m++ = MAGIC1; *m++ = MAGIC1; *m++ = MAGIC1; *m++ = MAGIC1;
|
|
return mem;
|
|
}
|
|
|
|
#ifdef MALLOC_STATS
|
|
_mstats.nrcopy++;
|
|
#endif
|
|
|
|
if (n < tocopy)
|
|
tocopy = n;
|
|
|
|
if ((m = malloc (n)) == 0)
|
|
return 0;
|
|
FASTCOPY (mem, m, tocopy);
|
|
free (mem);
|
|
return m;
|
|
}
|
|
|
|
PTR_T
|
|
memalign (alignment, size)
|
|
unsigned int alignment;
|
|
size_t size;
|
|
{
|
|
register char *ptr;
|
|
register char *aligned;
|
|
register union mhead *p;
|
|
|
|
ptr = malloc (size + alignment);
|
|
|
|
if (ptr == 0)
|
|
return 0;
|
|
/* If entire block has the desired alignment, just accept it. */
|
|
if (((int) ptr & (alignment - 1)) == 0)
|
|
return ptr;
|
|
/* Otherwise, get address of byte in the block that has that alignment. */
|
|
aligned = (char *) (((int) ptr + alignment - 1) & -alignment);
|
|
|
|
/* Store a suitable indication of how to free the block,
|
|
so that free can find the true beginning of it. */
|
|
p = (union mhead *) aligned - 1;
|
|
p->mh_nbytes = aligned - ptr;
|
|
p->mh_alloc = ISMEMALIGN;
|
|
return aligned;
|
|
}
|
|
|
|
#if !defined (HPUX)
|
|
/* This runs into trouble with getpagesize on HPUX, and Multimax machines.
|
|
Patching out seems cleaner than the ugly fix needed. */
|
|
PTR_T
|
|
valloc (size)
|
|
size_t size;
|
|
{
|
|
return memalign (getpagesize (), size);
|
|
}
|
|
#endif /* !HPUX */
|
|
|
|
#ifndef NO_CALLOC
|
|
PTR_T
|
|
calloc (n, s)
|
|
size_t n, s;
|
|
{
|
|
size_t total;
|
|
char *result;
|
|
|
|
total = n * s;
|
|
result = malloc (total);
|
|
if (result)
|
|
zmemset (result, 0, total);
|
|
return result;
|
|
}
|
|
|
|
void
|
|
cfree (p)
|
|
PTR_T p;
|
|
{
|
|
free (p);
|
|
}
|
|
#endif /* !NO_CALLOC */
|
|
|
|
#ifdef MALLOC_STATS
|
|
|
|
struct bucket_stats
|
|
malloc_bucket_stats (size)
|
|
int size;
|
|
{
|
|
struct bucket_stats v;
|
|
register union mhead *p;
|
|
|
|
v.nfree = 0;
|
|
|
|
if (size < 0 || size >= NBUCKETS)
|
|
{
|
|
v.blocksize = 0;
|
|
v.nused = v.nmal = v.nmorecore = v.nsplit = 0;
|
|
return v;
|
|
}
|
|
|
|
v.blocksize = 1 << (size + 3);
|
|
v.nused = _mstats.nmalloc[size];
|
|
v.nmal = _mstats.tmalloc[size];
|
|
v.nmorecore = _mstats.nmorecore[size];
|
|
v.nsplit = _mstats.nsplit[size];
|
|
|
|
for (p = nextf[size]; p; p = CHAIN (p))
|
|
v.nfree++;
|
|
|
|
return v;
|
|
}
|
|
|
|
/* Return a copy of _MSTATS, with two additional fields filled in:
|
|
BYTESFREE is the total number of bytes on free lists. BYTESUSED
|
|
is the total number of bytes in use. These two fields are fairly
|
|
expensive to compute, so we do it only when asked to. */
|
|
struct _malstats
|
|
malloc_stats ()
|
|
{
|
|
struct _malstats result;
|
|
struct bucket_stats v;
|
|
register int i;
|
|
|
|
result = _mstats;
|
|
result.bytesused = result.bytesfree = 0;
|
|
for (i = 0; i < NBUCKETS; i++)
|
|
{
|
|
v = malloc_bucket_stats (i);
|
|
result.bytesfree += v.nfree * v.blocksize;
|
|
result.bytesused += v.nused * v.blocksize;
|
|
}
|
|
return (result);
|
|
}
|
|
|
|
static void
|
|
_print_malloc_stats (s, fp)
|
|
char *s;
|
|
FILE *fp;
|
|
{
|
|
register int i;
|
|
int totused, totfree;
|
|
struct bucket_stats v;
|
|
|
|
fprintf (fp, "Memory allocation statistics: %s\n\tsize\tfree\tin use\ttotal\tmorecore\tsplit\n", s ? s : "");
|
|
for (i = totused = totfree = 0; i < NBUCKETS; i++)
|
|
{
|
|
v = malloc_bucket_stats (i);
|
|
fprintf (fp, "%12lu\t%4d\t%6d\t%5d\t%8d\t%5d\n", v.blocksize, v.nfree, v.nused, v.nmal, v.nmorecore, v.nsplit);
|
|
totfree += v.nfree * v.blocksize;
|
|
totused += v.nused * v.blocksize;
|
|
}
|
|
fprintf (fp, "\nTotal bytes in use: %d, total bytes free: %d\n",
|
|
totused, totfree);
|
|
fprintf (fp, "Total mallocs: %d, total frees: %d, total reallocs: %d (%d copies)\n",
|
|
_mstats.nmal, _mstats.nfre, _mstats.nrealloc, _mstats.nrcopy);
|
|
fprintf (fp, "Total sbrks: %d, total bytes via sbrk: %d\n",
|
|
_mstats.nsbrk, _mstats.tsbrk);
|
|
fprintf (fp, "Total blocks split: %d, total block coalesces: %d\n",
|
|
_mstats.tbsplit, _mstats.tbcoalesce);
|
|
}
|
|
|
|
void
|
|
print_malloc_stats (s)
|
|
char *s;
|
|
{
|
|
_print_malloc_stats (s, stderr);
|
|
}
|
|
|
|
#define TRACEROOT "/var/tmp/maltrace/trace."
|
|
extern char *inttostr ();
|
|
|
|
void
|
|
trace_malloc_stats (s)
|
|
char *s;
|
|
{
|
|
char ibuf[32], *ip;
|
|
char fname[64];
|
|
int p;
|
|
FILE *fp;
|
|
|
|
p = (int)getpid();
|
|
ip = inttostr(p, ibuf, sizeof(ibuf));
|
|
strcpy (fname, TRACEROOT);
|
|
strcat (fname, ip);
|
|
fp = fopen(fname, "w");
|
|
if (fp)
|
|
{
|
|
_print_malloc_stats (s, fp);
|
|
fflush(fp);
|
|
fclose(fp);
|
|
}
|
|
}
|
|
#endif /* MALLOC_STATS */
|