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diff --git a/lib/malloc/malloc.c b/lib/malloc/malloc.c
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+/* malloc.c - dynamic memory allocation for bash. */
+
+/* Copyright (C) 1985-2005 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.
+ */
+
+/*
+ * 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 MEMSCRAMBLE to have free() write 0xcf into memory as it's freed, to
+ uncover callers that refer to freed memory, and to have malloc() write 0xdf
+ into memory as it's allocated to avoid referring to previous contents. */
+
+/* SCO 3.2v4 getcwd and possibly other libc routines fail with MEMSCRAMBLE;
+ handled by configure. */
+
+#if defined (HAVE_CONFIG_H)
+# include <config.h>
+#endif /* HAVE_CONFIG_H */
+
+#if defined (SHELL)
+# include "bashtypes.h"
+# include "stdc.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
+
+#include <stdio.h>
+
+/* Define getpagesize () if the system does not. */
+#ifndef HAVE_GETPAGESIZE
+# include "getpagesize.h"
+#endif
+
+#include "imalloc.h"
+#ifdef MALLOC_STATS
+# include "mstats.h"
+#endif
+#ifdef MALLOC_REGISTER
+# include "table.h"
+#endif
+#ifdef MALLOC_WATCH
+# include "watch.h"
+#endif
+
+/* System-specific omissions. */
+#ifdef HPUX
+# define NO_VALLOC
+#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. */
+
+
+/* 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_bits16_t mi_magic2; /* should be == MAGIC2 */ /* 2 */
+ u_bits32_t mi_nbytes; /* # of bytes allocated */ /* 4 */
+ } 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
+
+#define MOVERHEAD sizeof(union mhead)
+#define MALIGN_MASK 7 /* one less than desired alignment */
+
+typedef union _malloc_guard {
+ char s[4];
+ u_bits32_t i;
+} mguard_t;
+
+/* 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)))
+
+/* 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 the 2 bytes before the block's real space (-4 bytes) */
+#define MAGIC2 0x5555
+#define MSLOP 4 /* 4 bytes extra for u_bits32_t size */
+
+/* How many bytes are actually allocated for a request of size N --
+ rounded up to nearest multiple of 8 after accounting for malloc
+ overhead. */
+#define ALLOCATED_BYTES(n) \
+ (((n) + MOVERHEAD + MSLOP + MALIGN_MASK) & ~MALIGN_MASK)
+
+#define ASSERT(p) \
+ do \
+ { \
+ if (!(p)) xbotch((PTR_T)0, ERR_ASSERT_FAILED, __STRING(p), file, line); \
+ } \
+ while (0)
+
+/* Minimum and maximum bucket indices for block splitting (and to bound
+ the search for a block to split). */
+#define SPLIT_MIN 2 /* XXX - was 3 */
+#define SPLIT_MID 11
+#define SPLIT_MAX 14
+
+/* Minimum and maximum bucket indices for block coalescing. */
+#define COMBINE_MIN 2
+#define COMBINE_MAX (pagebucket - 1) /* XXX */
+
+#define LESSCORE_MIN 10
+#define LESSCORE_FRC 13
+
+#define STARTBUCK 1
+
+/* Flags for the internal functions. */
+#define MALLOC_WRAPPER 0x01 /* wrapper function */
+#define MALLOC_INTERNAL 0x02 /* internal function calling another */
+#define MALLOC_NOTRACE 0x04 /* don't trace this allocation or free */
+#define MALLOC_NOREG 0x08 /* don't register this allocation or free */
+
+/* Future use. */
+#define ERR_DUPFREE 0x01
+#define ERR_UNALLOC 0x02
+#define ERR_UNDERFLOW 0x04
+#define ERR_ASSERT_FAILED 0x08
+
+/* Evaluates to true if NB is appropriate for bucket NU. NB is adjusted
+ appropriately by the caller to account for malloc overhead. This only
+ checks that the recorded size is not too big for the bucket. We
+ can't check whether or not it's in between NU and NU-1 because we
+ might have encountered a busy bucket when allocating and moved up to
+ the next size. */
+#define IN_BUCKET(nb, nu) ((nb) <= binsizes[(nu)])
+
+/* Use this when we want to be sure that NB is in bucket NU. */
+#define RIGHT_BUCKET(nb, nu) \
+ (((nb) > binsizes[(nu)-1]) && ((nb) <= binsizes[(nu)]))
+
+/* nextf[i] is free list of blocks of size 2**(i + 3) */
+
+static union mhead *nextf[NBUCKETS];
+
+/* busy[i] is nonzero while allocation or free 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. */
+
+static char *memtop; /* top of heap */
+
+static unsigned long binsizes[NBUCKETS] = {
+ 8UL, 16UL, 32UL, 64UL, 128UL, 256UL, 512UL, 1024UL, 2048UL, 4096UL,
+ 8192UL, 16384UL, 32768UL, 65536UL, 131072UL, 262144UL, 524288UL,
+ 1048576UL, 2097152UL, 4194304UL, 8388608UL, 16777216UL, 33554432UL,
+ 67108864UL, 134217728UL, 268435456UL, 536870912UL, 1073741824UL,
+ 2147483648UL, 4294967295UL
+};
+
+/* binsizes[x] == (1 << ((x) + 3)) */
+#define binsize(x) binsizes[(x)]
+
+/* Declarations for internal functions */
+static PTR_T internal_malloc __P((size_t, const char *, int, int));
+static PTR_T internal_realloc __P((PTR_T, size_t, const char *, int, int));
+static void internal_free __P((PTR_T, const char *, int, int));
+static PTR_T internal_memalign __P((size_t, size_t, const char *, int, int));
+#ifndef NO_CALLOC
+static PTR_T internal_calloc __P((size_t, size_t, const char *, int, int));
+static void internal_cfree __P((PTR_T, const char *, int, int));
+#endif
+#ifndef NO_VALLOC
+static PTR_T internal_valloc __P((size_t, const char *, int, int));
+#endif
+
+#if defined (botch)
+extern void botch ();
+#else
+static void botch __P((const char *, const char *, int));
+#endif
+static void xbotch __P((PTR_T, int, const char *, const char *, int));
+
+#if !HAVE_DECL_SBRK
+extern char *sbrk ();
+#endif /* !HAVE_DECL_SBRK */
+
+#ifdef SHELL
+extern int interrupt_immediately;
+extern int signal_is_trapped __P((int));
+#endif
+
+#ifdef MALLOC_STATS
+struct _malstats _mstats;
+#endif /* MALLOC_STATS */
+
+/* Debugging variables available to applications. */
+int malloc_flags = 0; /* future use */
+int malloc_trace = 0; /* trace allocations and frees to stderr */
+int malloc_register = 0; /* future use */
+
+#ifdef MALLOC_TRACE
+char _malloc_trace_buckets[NBUCKETS];
+
+/* These should really go into a header file. */
+extern void mtrace_alloc __P((const char *, PTR_T, size_t, const char *, int));
+extern void mtrace_free __P((PTR_T, int, const char *, int));
+#endif
+
+#if !defined (botch)
+static void
+botch (s, file, line)
+ const char *s;
+ const char *file;
+ int line;
+{
+ fprintf (stderr, _("malloc: failed assertion: %s\n"), s);
+ (void)fflush (stderr);
+ abort ();
+}
+#endif
+
+/* print the file and line number that caused the assertion failure and
+ call botch() to do whatever the application wants with the information */
+static void
+xbotch (mem, e, s, file, line)
+ PTR_T mem;
+ int e;
+ const char *s;
+ const char *file;
+ int line;
+{
+ fprintf (stderr, _("\r\nmalloc: %s:%d: assertion botched\r\n"),
+ file ? file : "unknown", line);
+#ifdef MALLOC_REGISTER
+ if (mem != NULL && malloc_register)
+ mregister_describe_mem (mem, stderr);
+#endif
+ (void)fflush (stderr);
+ botch(s, file, line);
+}
+
+/* Coalesce two adjacent free blocks off the free list for size NU - 1,
+ as long as we can find two adjacent free blocks. nextf[NU -1] is
+ assumed to not be busy; the caller (morecore()) checks for this.
+ BUSY[NU] must be set to 1. */
+static void
+bcoalesce (nu)
+ register int nu;
+{
+ register union mhead *mp, *mp1, *mp2;
+ register int nbuck;
+ unsigned long siz;
+
+ nbuck = nu - 1;
+ if (nextf[nbuck] == 0 || busy[nbuck])
+ return;
+
+ busy[nbuck] = 1;
+ siz = binsize (nbuck);
+
+ mp2 = mp1 = nextf[nbuck];
+ mp = CHAIN (mp1);
+ while (mp && mp != (union mhead *)((char *)mp1 + siz))
+ {
+ mp2 = mp1;
+ mp1 = mp;
+ mp = CHAIN (mp);
+ }
+
+ if (mp == 0)
+ {
+ busy[nbuck] = 0;
+ 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 (mp2 != mp1 && CHAIN(mp2) != mp1)
+ {
+ busy[nbuck] = 0;
+ xbotch ((PTR_T)0, 0, "bcoalesce: CHAIN(mp2) != mp1", (char *)NULL, 0);
+ }
+
+#ifdef MALLOC_DEBUG
+ if (CHAIN (mp1) != (union mhead *)((char *)mp1 + siz))
+ {
+ busy[nbuck] = 0;
+ return; /* not adjacent */
+ }
+#endif
+
+ /* Since they are adjacent, remove them from the free list */
+ if (mp1 == nextf[nbuck])
+ nextf[nbuck] = CHAIN (mp);
+ else
+ CHAIN (mp2) = CHAIN (mp);
+ busy[nbuck] = 0;
+
+#ifdef MALLOC_STATS
+ _mstats.tbcoalesce++;
+ _mstats.ncoalesce[nbuck]++;
+#endif
+
+ /* And add the combined two blocks to nextf[NU]. */
+ mp1->mh_alloc = ISFREE;
+ mp1->mh_index = nu;
+ CHAIN (mp1) = nextf[nu];
+ nextf[nu] = mp1;
+}
+
+/* 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()). BUSY[NU] must be set to 1. */
+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. */
+
+ /* Remove the block from the chain of larger blocks. */
+ busy[nbuck] = 1;
+ mp = nextf[nbuck];
+ nextf[nbuck] = CHAIN (mp);
+ busy[nbuck] = 0;
+
+#ifdef MALLOC_STATS
+ _mstats.tbsplit++;
+ _mstats.nsplit[nbuck]++;
+#endif
+
+ /* Figure out how many blocks we'll get. */
+ siz = binsize (nu);
+ nblks = binsize (nbuck) / siz;
+
+ /* 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;
+}
+
+/* Take the memory block MP and add it to a chain < NU. NU is the right bucket,
+ but is busy. This avoids memory orphaning. */
+static void
+xsplit (mp, nu)
+ union mhead *mp;
+ int nu;
+{
+ union mhead *nh;
+ int nbuck, nblks, split_max;
+ unsigned long siz;
+
+ nbuck = nu - 1;
+ while (nbuck >= SPLIT_MIN && busy[nbuck])
+ nbuck--;
+ if (nbuck < SPLIT_MIN)
+ return;
+
+#ifdef MALLOC_STATS
+ _mstats.tbsplit++;
+ _mstats.nsplit[nu]++;
+#endif
+
+ /* Figure out how many blocks we'll get. */
+ siz = binsize (nu); /* original block size */
+ nblks = siz / binsize (nbuck); /* should be 2 most of the time */
+
+ /* And add it to nextf[nbuck] */
+ siz = binsize (nbuck); /* XXX - resetting here */
+ nh = mp;
+ while (1)
+ {
+ mp->mh_alloc = ISFREE;
+ mp->mh_index = nbuck;
+ if (--nblks <= 0) break;
+ CHAIN (mp) = (union mhead *)((char *)mp + siz);
+ mp = (union mhead *)((char *)mp + siz);
+ }
+ busy[nbuck] = 1;
+ CHAIN (mp) = nextf[nbuck];
+ nextf[nbuck] = nh;
+ busy[nbuck] = 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
+}
+
+/* Return some memory to the system by reducing the break. This is only
+ called with NU > pagebucket, so we're always assured of giving back
+ more than one page of memory. */
+static void
+lesscore (nu) /* give system back some memory */
+ register int nu; /* size index we're discarding */
+{
+ long siz;
+
+ siz = binsize (nu);
+ /* Should check for errors here, I guess. */
+ sbrk (-siz);
+ memtop -= siz;
+
+#ifdef MALLOC_STATS
+ _mstats.nsbrk++;
+ _mstats.tsbrk -= siz;
+ _mstats.nlesscore[nu]++;
+#endif
+}
+
+/* Ask system for more memory; add to NEXTF[NU]. BUSY[NU] must be set to 1. */
+static void
+morecore (nu)
+ 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 = binsize (nu); /* 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 (nu >= SPLIT_MIN)
+ {
+ bsplit (nu);
+ if (nextf[nu] != 0)
+ goto morecore_done;
+ }
+
+ /* Try to coalesce two adjacent blocks from the free list on nextf[nu - 1],
+ if we can, and we're within 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;
+ }
+
+ /* 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 - 1);
+ 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;
+
+ memtop += sbrk_amt;
+
+ /* shouldn't happen, but just in case -- require 8-byte alignment */
+ if ((long)mp & MALIGN_MASK)
+ {
+ mp = (union mhead *) (((long)mp + MALIGN_MASK) & ~MALIGN_MASK);
+ 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);
+}
+
+static void
+malloc_debug_dummy ()
+{
+ write (1, "malloc_debug_dummy\n", 19);
+}
+
+#define PREPOP_BIN 2
+#define PREPOP_SIZE 32
+
+static int
+pagealign ()
+{
+ register int nunits;
+ register union mhead *mp;
+ long sbrk_needed;
+ char *curbrk;
+
+ pagesz = getpagesize ();
+ if (pagesz < 1024)
+ pagesz = 1024;
+
+ /* OK, how much do we need to allocate to make things page-aligned?
+ Some of this partial page will be wasted space, but we'll use as
+ much as we can. Once we figure out how much to advance the break
+ pointer, go ahead and do it. */
+ memtop = curbrk = sbrk (0);
+ sbrk_needed = pagesz - ((long)curbrk & (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
+ curbrk = sbrk (sbrk_needed);
+ if ((long)curbrk == -1)
+ return -1;
+ memtop += sbrk_needed;
+
+ /* Take the memory which would otherwise be wasted and populate the most
+ popular bin (2 == 32 bytes) with it. Add whatever we need to curbrk
+ to make things 32-byte aligned, compute how many 32-byte chunks we're
+ going to get, and set up the bin. */
+ curbrk += sbrk_needed & (PREPOP_SIZE - 1);
+ sbrk_needed -= sbrk_needed & (PREPOP_SIZE - 1);
+ nunits = sbrk_needed / PREPOP_SIZE;
+
+ if (nunits > 0)
+ {
+ mp = (union mhead *)curbrk;
+
+ nextf[PREPOP_BIN] = mp;
+ while (1)
+ {
+ mp->mh_alloc = ISFREE;
+ mp->mh_index = PREPOP_BIN;
+ if (--nunits <= 0) break;
+ CHAIN(mp) = (union mhead *)((char *)mp + PREPOP_SIZE);
+ mp = (union mhead *)((char *)mp + PREPOP_SIZE);
+ }
+ CHAIN(mp) = 0;
+ }
+ }
+
+ /* compute which bin corresponds to the page size. */
+ for (nunits = 7; nunits < NBUCKETS; nunits++)
+ if (pagesz <= binsize(nunits))
+ break;
+ pagebucket = nunits;
+
+ return 0;
+}
+
+static PTR_T
+internal_malloc (n, file, line, flags) /* get a block */
+ size_t n;
+ const char *file;
+ int line, flags;
+{
+ register union mhead *p;
+ register int nunits;
+ register char *m, *z;
+ long nbytes;
+ mguard_t mg;
+
+ /* Get the system page size and align break pointer so future sbrks will
+ be page-aligned. The page size must be at least 1K -- anything
+ smaller is increased. */
+ if (pagesz == 0)
+ if (pagealign () < 0)
+ return ((PTR_T)NULL);
+
+ /* Figure out how many bytes are required, rounding up to the nearest
+ multiple of 8, 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 = ALLOCATED_BYTES(n);
+ nunits = (nbytes <= (pagesz >> 1)) ? STARTBUCK : pagebucket;
+ for ( ; nunits < NBUCKETS; nunits++)
+ if (nbytes <= binsize(nunits))
+ break;
+
+ /* Silently reject too-large requests. */
+ if (nunits >= NBUCKETS)
+ return ((PTR_T) NULL);
+
+ /* 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)
+ xbotch ((PTR_T)(p+1), 0, _("malloc: block on free list clobbered"), file, line);
+
+ /* Fill in the info, and set up the magic numbers for range checking. */
+ p->mh_alloc = ISALLOC;
+ p->mh_magic2 = MAGIC2;
+ p->mh_nbytes = n;
+
+ /* End guard */
+ mg.i = n;
+ z = mg.s;
+ m = (char *) (p + 1) + n;
+ *m++ = *z++, *m++ = *z++, *m++ = *z++, *m++ = *z++;
+
+#ifdef MEMSCRAMBLE
+ if (n)
+ MALLOC_MEMSET ((char *)(p + 1), 0xdf, n); /* scramble previous contents */
+#endif
+#ifdef MALLOC_STATS
+ _mstats.nmalloc[nunits]++;
+ _mstats.tmalloc[nunits]++;
+ _mstats.nmal++;
+ _mstats.bytesreq += n;
+#endif /* MALLOC_STATS */
+
+#ifdef MALLOC_TRACE
+ if (malloc_trace && (flags & MALLOC_NOTRACE) == 0)
+ mtrace_alloc ("malloc", p + 1, n, file, line);
+ else if (_malloc_trace_buckets[nunits])
+ mtrace_alloc ("malloc", p + 1, n, file, line);
+#endif
+
+#ifdef MALLOC_REGISTER
+ if (malloc_register && (flags & MALLOC_NOREG) == 0)
+ mregister_alloc ("malloc", p + 1, n, file, line);
+#endif
+
+#ifdef MALLOC_WATCH
+ if (_malloc_nwatch > 0)
+ _malloc_ckwatch (p + 1, file, line, W_ALLOC, n);
+#endif
+
+ return (PTR_T) (p + 1);
+}
+
+static void
+internal_free (mem, file, line, flags)
+ PTR_T mem;
+ const char *file;
+ int line, flags;
+{
+ register union mhead *p;
+ register char *ap, *z;
+ register int nunits;
+ register unsigned int nbytes;
+ int ubytes; /* caller-requested size */
+ mguard_t mg;
+
+ 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 defined (MALLOC_TRACE) || defined (MALLOC_REGISTER)
+ if (malloc_trace || malloc_register)
+ ubytes = p->mh_nbytes;
+#endif
+
+ if (p->mh_alloc != ISALLOC)
+ {
+ if (p->mh_alloc == ISFREE)
+ xbotch (mem, ERR_DUPFREE,
+ _("free: called with already freed block argument"), file, line);
+ else
+ xbotch (mem, ERR_UNALLOC,
+ _("free: called with unallocated block argument"), file, line);
+ }
+
+ ASSERT (p->mh_magic2 == MAGIC2);
+
+ nunits = p->mh_index;
+ nbytes = ALLOCATED_BYTES(p->mh_nbytes);
+ /* Since the sizeof(u_bits32_t) bytes before the memory handed to the user
+ are now used for the number of bytes allocated, a simple check of
+ mh_magic2 is no longer sufficient to catch things like p[-1] = 'x'.
+ We sanity-check the value of mh_nbytes against the size of the blocks
+ in the appropriate bucket before we use it. This can still cause problems
+ and obscure errors if mh_nbytes is wrong but still within range; the
+ checks against the size recorded at the end of the chunk will probably
+ fail then. Using MALLOC_REGISTER will help here, since it saves the
+ original number of bytes requested. */
+
+ if (IN_BUCKET(nbytes, nunits) == 0)
+ xbotch (mem, ERR_UNDERFLOW,
+ _("free: underflow detected; mh_nbytes out of range"), file, line);
+
+ ap += p->mh_nbytes;
+ z = mg.s;
+ *z++ = *ap++, *z++ = *ap++, *z++ = *ap++, *z++ = *ap++;
+ if (mg.i != p->mh_nbytes)
+ xbotch (mem, ERR_ASSERT_FAILED, _("free: start and end chunk sizes differ"), file, line);
+
+#if 1
+ if (nunits >= LESSCORE_MIN && ((char *)p + binsize(nunits) == memtop))
+#else
+ if (((char *)p + binsize(nunits) == memtop) && nunits >= LESSCORE_MIN)
+#endif
+ {
+ /* If above LESSCORE_FRC, give back unconditionally. This should be set
+ high enough to be infrequently encountered. If between LESSCORE_MIN
+ and LESSCORE_FRC, call lesscore if the bucket is marked as busy or if
+ there's already a block on the free list. */
+ if ((nunits >= LESSCORE_FRC) || busy[nunits] || nextf[nunits] != 0)
+ {
+ lesscore (nunits);
+ /* keeps the tracing and registering code in one place */
+ goto free_return;
+ }
+ }
+
+#ifdef MEMSCRAMBLE
+ if (p->mh_nbytes)
+ MALLOC_MEMSET (mem, 0xcf, p->mh_nbytes);
+#endif
+
+ ASSERT (nunits < NBUCKETS);
+
+ if (busy[nunits] == 1)
+ {
+ xsplit (p, nunits); /* split block and add to different chain */
+ goto free_return;
+ }
+
+ p->mh_alloc = ISFREE;
+ /* 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;
+
+free_return:
+ ; /* Empty statement in case this is the end of the function */
+
+#ifdef MALLOC_STATS
+ _mstats.nmalloc[nunits]--;
+ _mstats.nfre++;
+#endif /* MALLOC_STATS */
+
+#ifdef MALLOC_TRACE
+ if (malloc_trace && (flags & MALLOC_NOTRACE) == 0)
+ mtrace_free (mem, ubytes, file, line);
+ else if (_malloc_trace_buckets[nunits])
+ mtrace_free (mem, ubytes, file, line);
+#endif
+
+#ifdef MALLOC_REGISTER
+ if (malloc_register && (flags & MALLOC_NOREG) == 0)
+ mregister_free (mem, ubytes, file, line);
+#endif
+
+#ifdef MALLOC_WATCH
+ if (_malloc_nwatch > 0)
+ _malloc_ckwatch (mem, file, line, W_FREE, ubytes);
+#endif
+}
+
+static PTR_T
+internal_realloc (mem, n, file, line, flags)
+ PTR_T mem;
+ register size_t n;
+ const char *file;
+ int line, flags;
+{
+ register union mhead *p;
+ register u_bits32_t tocopy;
+ register unsigned int nbytes;
+ register int nunits;
+ register char *m, *z;
+ mguard_t mg;
+
+#ifdef MALLOC_STATS
+ _mstats.nrealloc++;
+#endif
+
+ if (n == 0)
+ {
+ internal_free (mem, file, line, MALLOC_INTERNAL);
+ return (NULL);
+ }
+ if ((p = (union mhead *) mem) == 0)
+ return internal_malloc (n, file, line, MALLOC_INTERNAL);
+
+ p--;
+ nunits = p->mh_index;
+ ASSERT (nunits < NBUCKETS);
+
+ if (p->mh_alloc != ISALLOC)
+ xbotch (mem, ERR_UNALLOC,
+ _("realloc: called with unallocated block argument"), file, line);
+
+ ASSERT (p->mh_magic2 == MAGIC2);
+ nbytes = ALLOCATED_BYTES(p->mh_nbytes);
+ /* Since the sizeof(u_bits32_t) bytes before the memory handed to the user
+ are now used for the number of bytes allocated, a simple check of
+ mh_magic2 is no longer sufficient to catch things like p[-1] = 'x'.
+ We sanity-check the value of mh_nbytes against the size of the blocks
+ in the appropriate bucket before we use it. This can still cause problems
+ and obscure errors if mh_nbytes is wrong but still within range; the
+ checks against the size recorded at the end of the chunk will probably
+ fail then. Using MALLOC_REGISTER will help here, since it saves the
+ original number of bytes requested. */
+ if (IN_BUCKET(nbytes, nunits) == 0)
+ xbotch (mem, ERR_UNDERFLOW,
+ _("realloc: underflow detected; mh_nbytes out of range"), file, line);
+
+ m = (char *)mem + (tocopy = p->mh_nbytes);
+ z = mg.s;
+ *z++ = *m++, *z++ = *m++, *z++ = *m++, *z++ = *m++;
+ if (mg.i != p->mh_nbytes)
+ xbotch (mem, ERR_ASSERT_FAILED, _("realloc: start and end chunk sizes differ"), file, line);
+
+#ifdef MALLOC_WATCH
+ if (_malloc_nwatch > 0)
+ _malloc_ckwatch (p + 1, file, line, W_REALLOC, n);
+#endif
+#ifdef MALLOC_STATS
+ _mstats.bytesreq += (n < tocopy) ? 0 : n - tocopy;
+#endif
+
+ /* See if desired size rounds to same power of 2 as actual size. */
+ nbytes = ALLOCATED_BYTES(n);
+
+ /* If ok, use the same block, just marking its size as changed. */
+ if (RIGHT_BUCKET(nbytes, nunits))
+ {
+#if 0
+ m = (char *)mem + p->mh_nbytes;
+#else
+ /* Compensate for increment above. */
+ m -= 4;
+#endif
+ *m++ = 0; *m++ = 0; *m++ = 0; *m++ = 0;
+ m = (char *)mem + (p->mh_nbytes = n);
+
+ mg.i = n;
+ z = mg.s;
+ *m++ = *z++, *m++ = *z++, *m++ = *z++, *m++ = *z++;
+
+ return mem;
+ }
+
+ if (n < tocopy)
+ tocopy = n;
+
+#ifdef MALLOC_STATS
+ _mstats.nrcopy++;
+#endif
+
+ if ((m = internal_malloc (n, file, line, MALLOC_INTERNAL|MALLOC_NOTRACE|MALLOC_NOREG)) == 0)
+ return 0;
+ FASTCOPY (mem, m, tocopy);
+ internal_free (mem, file, line, MALLOC_INTERNAL);
+
+#ifdef MALLOC_TRACE
+ if (malloc_trace && (flags & MALLOC_NOTRACE) == 0)
+ mtrace_alloc ("realloc", m, n, file, line);
+ else if (_malloc_trace_buckets[nunits])
+ mtrace_alloc ("realloc", m, n, file, line);
+#endif
+
+#ifdef MALLOC_REGISTER
+ if (malloc_register && (flags & MALLOC_NOREG) == 0)
+ mregister_alloc ("realloc", m, n, file, line);
+#endif
+
+#ifdef MALLOC_WATCH
+ if (_malloc_nwatch > 0)
+ _malloc_ckwatch (m, file, line, W_RESIZED, n);
+#endif
+
+ return m;
+}
+
+static PTR_T
+internal_memalign (alignment, size, file, line, flags)
+ size_t alignment;
+ size_t size;
+ const char *file;
+ int line, flags;
+{
+ register char *ptr;
+ register char *aligned;
+ register union mhead *p;
+
+ ptr = internal_malloc (size + alignment, file, line, MALLOC_INTERNAL);
+
+ if (ptr == 0)
+ return 0;
+ /* If entire block has the desired alignment, just accept it. */
+ if (((long) ptr & (alignment - 1)) == 0)
+ return ptr;
+ /* Otherwise, get address of byte in the block that has that alignment. */
+#if 0
+ aligned = (char *) (((long) ptr + alignment - 1) & -alignment);
+#else
+ aligned = (char *) (((long) ptr + alignment - 1) & (~alignment + 1));
+#endif
+
+ /* 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 (NO_VALLOC)
+/* This runs into trouble with getpagesize on HPUX, and Multimax machines.
+ Patching out seems cleaner than the ugly fix needed. */
+static PTR_T
+internal_valloc (size, file, line, flags)
+ size_t size;
+ const char *file;
+ int line, flags;
+{
+ return internal_memalign (getpagesize (), size, file, line, flags|MALLOC_INTERNAL);
+}
+#endif /* !NO_VALLOC */
+
+#ifndef NO_CALLOC
+static PTR_T
+internal_calloc (n, s, file, line, flags)
+ size_t n, s;
+ const char *file;
+ int line, flags;
+{
+ size_t total;
+ PTR_T result;
+
+ total = n * s;
+ result = internal_malloc (total, file, line, flags|MALLOC_INTERNAL);
+ if (result)
+ memset (result, 0, total);
+ return result;
+}
+
+static void
+internal_cfree (p, file, line, flags)
+ PTR_T p;
+ const char *file;
+ int line, flags;
+{
+ internal_free (p, file, line, flags|MALLOC_INTERNAL);
+}
+#endif /* !NO_CALLOC */
+
+#ifdef MALLOC_STATS
+int
+malloc_free_blocks (size)
+ int size;
+{
+ int nfree;
+ register union mhead *p;
+
+ nfree = 0;
+ for (p = nextf[size]; p; p = CHAIN (p))
+ nfree++;
+
+ return nfree;
+}
+#endif
+
+#if defined (MALLOC_WRAPFUNCS)
+PTR_T
+sh_malloc (bytes, file, line)
+ size_t bytes;
+ const char *file;
+ int line;
+{
+ return internal_malloc (bytes, file, line, MALLOC_WRAPPER);
+}
+
+PTR_T
+sh_realloc (ptr, size, file, line)
+ PTR_T ptr;
+ size_t size;
+ const char *file;
+ int line;
+{
+ return internal_realloc (ptr, size, file, line, MALLOC_WRAPPER);
+}
+
+void
+sh_free (mem, file, line)
+ PTR_T mem;
+ const char *file;
+ int line;
+{
+ internal_free (mem, file, line, MALLOC_WRAPPER);
+}
+
+PTR_T
+sh_memalign (alignment, size, file, line)
+ size_t alignment;
+ size_t size;
+ const char *file;
+ int line;
+{
+ return internal_memalign (alignment, size, file, line, MALLOC_WRAPPER);
+}
+
+#ifndef NO_CALLOC
+PTR_T
+sh_calloc (n, s, file, line)
+ size_t n, s;
+ const char *file;
+ int line;
+{
+ return internal_calloc (n, s, file, line, MALLOC_WRAPPER);
+}
+
+void
+sh_cfree (mem, file, line)
+ PTR_T mem;
+ const char *file;
+ int line;
+{
+ internal_cfree (mem, file, line, MALLOC_WRAPPER);
+}
+#endif
+
+#ifndef NO_VALLOC
+PTR_T
+sh_valloc (size, file, line)
+ size_t size;
+ const char *file;
+ int line;
+{
+ return internal_valloc (size, file, line, MALLOC_WRAPPER);
+}
+#endif /* !NO_VALLOC */
+
+#endif /* MALLOC_WRAPFUNCS */
+
+/* Externally-available functions that call their internal counterparts. */
+
+PTR_T
+malloc (size)
+ size_t size;
+{
+ return internal_malloc (size, (char *)NULL, 0, 0);
+}
+
+PTR_T
+realloc (mem, nbytes)
+ PTR_T mem;
+ size_t nbytes;
+{
+ return internal_realloc (mem, nbytes, (char *)NULL, 0, 0);
+}
+
+void
+free (mem)
+ PTR_T mem;
+{
+ internal_free (mem, (char *)NULL, 0, 0);
+}
+
+PTR_T
+memalign (alignment, size)
+ size_t alignment;
+ size_t size;
+{
+ return internal_memalign (alignment, size, (char *)NULL, 0, 0);
+}
+
+#ifndef NO_VALLOC
+PTR_T
+valloc (size)
+ size_t size;
+{
+ return internal_valloc (size, (char *)NULL, 0, 0);
+}
+#endif
+
+#ifndef NO_CALLOC
+PTR_T
+calloc (n, s)
+ size_t n, s;
+{
+ return internal_calloc (n, s, (char *)NULL, 0, 0);
+}
+
+void
+cfree (mem)
+ PTR_T mem;
+{
+ internal_cfree (mem, (char *)NULL, 0, 0);
+}
+#endif