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diff --git a/nx-X11/programs/Xserver/os/xalloc.c b/nx-X11/programs/Xserver/os/xalloc.c
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+#define FATALERRORS 1
+/*
+Copyright (C) 1995 Pascal Haible. All Rights Reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+PASCAL HAIBLE BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
+OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+
+Except as contained in this notice, the name of Pascal Haible shall
+not be used in advertising or otherwise to promote the sale, use or other
+dealings in this Software without prior written authorization from
+Pascal Haible.
+*/
+
+/* $XFree86: xc/programs/Xserver/os/xalloc.c,v 3.35tsi Exp $ */
+
+/* Only used if INTERNAL_MALLOC is defined
+ * - otherwise xalloc() in utils.c is used
+ */
+#ifdef HAVE_DIX_CONFIG_H
+#include <dix-config.h>
+#endif
+
+#ifdef INTERNAL_MALLOC
+
+#include <stdlib.h> /* for malloc() etc. */
+
+#include <X11/Xos.h>
+#include "misc.h"
+#include <X11/X.h>
+
+#ifdef XALLOC_LOG
+#include <stdio.h>
+#endif
+
+extern Bool Must_have_memory;
+
+/*
+ ***** New malloc approach for the X server *****
+ * Pascal Haible 1995
+ *
+ * Some statistics about memory allocation of the X server
+ * The test session included several clients of different size, including
+ * xv, emacs and xpaint with a new canvas of 3000x2000, zoom 5.
+ * All clients were running together.
+ * A protocolling version of Xalloc recorded 318917 allocating actions
+ * (191573 Xalloc, 85942 XNFalloc, 41438 Xrealloc, 279727 Xfree).
+ * Results grouped by size, excluding the next lower size
+ * (i.e. size=32 means 16<size<=32):
+ *
+ * size nr of alloc max nr of blocks allocated together
+ * 8 1114 287
+ * 16 17341 4104
+ * 32 147352 2068
+ * 64 59053 2518
+ * 128 46882 1230
+ * 256 20544 1217
+ * 512 6808 117
+ * 1024 8254 171
+ * 2048 4841 287
+ * 4096 2429 84
+ * 8192 3364 85
+ * 16384 573 22
+ * 32768 49 7
+ * 65536 45 5
+ * 131072 48 2
+ * 262144 209 2
+ * 524288 7 4
+ * 1048576 2 1
+ * 8388608 2 2
+ *
+ * The most used sizes:
+ * count size
+ * 24 136267
+ * 40 37055
+ * 72 17278
+ * 56 13504
+ * 80 9372
+ * 16 8966
+ * 32 8411
+ * 136 8399
+ * 104 7690
+ * 12 7630
+ * 120 5512
+ * 88 4634
+ * 152 3062
+ * 52 2881
+ * 48 2736
+ * 156 1569
+ * 168 1487
+ * 160 1483
+ * 28 1446
+ * 1608 1379
+ * 184 1305
+ * 552 1270
+ * 64 934
+ * 320 891
+ * 8 754
+ *
+ * Conclusions: more than the half of all allocations are <= 32 bytes.
+ * But of these about 150,000 blocks, only a maximum of about 6,000 are
+ * allocated together (including memory leaks..).
+ * On the other side, only 935 of the 191573 or 0.5% were larger than 8kB
+ * (362 or 0.2% larger than 16k).
+ *
+ * What makes the server really grow is the fragmentation of the heap,
+ * and the fact that it can't shrink.
+ * To cure this, we do the following:
+ * - large blocks (>=11k) are mmapped on xalloc, and unmapped on xfree,
+ * so we don't need any free lists etc.
+ * As this needs 2 system calls, we only do this for the quite
+ * infrequent large (>=11k) blocks.
+ * - instead of reinventing the wheel, we use system malloc for medium
+ * sized blocks (>256, <11k).
+ * - for small blocks (<=256) we use an other approach:
+ * As we need many small blocks, and most ones for a short time,
+ * we don't go through the system malloc:
+ * for each fixed sizes a seperate list of free blocks is kept.
+ * to KISS (Keep it Small and Simple), we don't free them
+ * (not freeing a block of 32 bytes won't be worse than having fragmented
+ * a larger area on allocation).
+ * This way, we (almost) allways have a fitting free block right at hand,
+ * and don't have to walk any lists.
+ */
+
+/*
+ * structure layout of a allocated block
+ * unsigned long size:
+ * rounded up netto size for small and medium blocks
+ * brutto size == mmap'ed area for large blocks
+ * unsigned long DEBUG ? MAGIC : unused
+ * .... data
+ * ( unsigned long MAGIC2 ) only if SIZE_TAIL defined
+ *
+ */
+
+/* use otherwise unused long in the header to store a magic */
+/* shouldn't this be removed for production release ? */
+#define XALLOC_DEBUG
+
+#ifdef XALLOC_DEBUG
+/* Xfree fills the memory with a certain pattern (currently 0xF0) */
+/* this should really be removed for production release! */
+#define XFREE_ERASES
+#endif
+
+/* this must be a multiple of SIZE_STEPS below */
+#define MAX_SMALL 264 /* quite many blocks of 264 */
+
+#define MIN_LARGE (11*1024)
+/* worst case is 25% loss with a page size of 4k */
+
+/* SIZE_STEPS defines the granularity of size of small blocks -
+ * this makes blocks align to that, too! */
+#define SIZE_STEPS (sizeof(double))
+#define SIZE_HEADER (2*sizeof(long)) /* = sizeof(double) for 32bit */
+#ifdef XALLOC_DEBUG
+#if defined(__sparc__)
+#define SIZE_TAIL (2*sizeof(long)) /* = sizeof(double) for 32bit */
+#else
+#define SIZE_TAIL (sizeof(long))
+#endif
+#endif
+
+#undef TAIL_SIZE
+#ifdef SIZE_TAIL
+#define TAIL_SIZE SIZE_TAIL
+#else
+#define TAIL_SIZE 0
+#endif
+
+#if defined (_LP64) || \
+ defined(__alpha__) || defined(__alpha) || \
+ defined(__ia64__) || defined(ia64) || \
+ defined(__sparc64__) || \
+ defined(__s390x__) || \
+ defined(__amd64__) || defined(amd64) || \
+ defined(__powerpc64__) || \
+ (defined(sgi) && _MIPS_SZLONG == 64))
+#define MAGIC 0x1404196414071968
+#define MAGIC_FREE 0x1506196615061966
+#define MAGIC2 0x2515207525182079
+#else
+#define MAGIC 0x14071968
+#define MAGIC_FREE 0x15061966
+#define MAGIC2 0x25182079
+#endif
+
+/* To get some statistics about memory allocation */
+
+#ifdef XALLOC_LOG
+#define XALLOC_LOG_FILE "/tmp/Xalloc.log" /* unsecure... */
+#define LOG_BODY(_body) \
+ { FILE *f; \
+ f = fopen(XALLOC_LOG_FILE, "a"); \
+ if (NULL!=f) { \
+ _body; \
+ fclose(f); \
+ } \
+ }
+#if defined(linux) && defined(i386)
+#define LOG_ALLOC(_fun, _size, _ret) \
+ { unsigned long *from; \
+ __asm__("movl %%ebp,%0" : /*OUT*/ "=r" (from) : /*IN*/ ); \
+ LOG_BODY(fprintf(f, "%s\t%i\t%p\t[%lu]\n", _fun, _size, _ret, *(from+1))) \
+ }
+#else
+#define LOG_ALLOC(_fun, _size, _ret) \
+ LOG_BODY(fprintf(f, "%s\t%i\t%p\n", _fun, _size, _ret))
+#endif
+#define LOG_REALLOC(_fun, _ptr, _size, _ret) \
+ LOG_BODY(fprintf(f, "%s\t%p\t%i\t%p\n", _fun, _ptr, _size, _ret))
+#define LOG_FREE(_fun, _ptr) \
+ LOG_BODY(fprintf(f, "%s\t%p\n", _fun, _ptr))
+#else
+#define LOG_ALLOC(_fun, _size, _ret)
+#define LOG_REALLOC(_fun, _ptr, _size, _ret)
+#define LOG_FREE(_fun, _ptr)
+#endif /* XALLOC_LOG */
+
+static unsigned long *free_lists[MAX_SMALL/SIZE_STEPS];
+
+/*
+ * systems that support it should define HAS_MMAP_ANON or MMAP_DEV_ZERO
+ * and include the appropriate header files for
+ * mmap(), munmap(), PROT_READ, PROT_WRITE, MAP_PRIVATE,
+ * PAGE_SIZE or _SC_PAGESIZE (and MAP_ANON for HAS_MMAP_ANON).
+ *
+ * systems that don't support MAP_ANON fall through to the 2 fold behaviour
+ */
+
+#if defined(linux)
+#define HAS_MMAP_ANON
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <asm/page.h> /* PAGE_SIZE */
+#define HAS_SC_PAGESIZE /* _SC_PAGESIZE may be an enum for Linux */
+#define HAS_GETPAGESIZE
+#endif /* linux */
+
+#if defined(__GNU__)
+#define HAS_MMAP_ANON
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <mach/vm_param.h> /* PAGE_SIZE */
+#define HAS_SC_PAGESIZE
+#define HAS_GETPAGESIZE
+#endif /* __GNU__ */
+
+#if defined(CSRG_BASED)
+#define HAS_MMAP_ANON
+#define HAS_GETPAGESIZE
+#include <sys/types.h>
+#include <sys/mman.h>
+#endif /* CSRG_BASED */
+
+#if defined(DGUX)
+#define HAS_GETPAGESIZE
+#define MMAP_DEV_ZERO
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#endif /* DGUX */
+
+#if defined(SVR4) && !defined(DGUX)
+#define MMAP_DEV_ZERO
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#endif /* SVR4 && !DGUX */
+
+#if defined(sun) && !defined(SVR4) /* SunOS */
+#define MMAP_DEV_ZERO /* doesn't SunOS have MAP_ANON ?? */
+#define HAS_GETPAGESIZE
+#include <sys/types.h>
+#include <sys/mman.h>
+#endif /* sun && !SVR4 */
+
+#ifdef XNO_SYSCONF
+#undef _SC_PAGESIZE
+#endif
+
+#if defined(HAS_MMAP_ANON) || defined (MMAP_DEV_ZERO)
+static int pagesize;
+#endif
+
+#ifdef MMAP_DEV_ZERO
+static int devzerofd = -1;
+#include <errno.h>
+#endif
+
+/*
+ * empty trap function for gdb. Breakpoint here
+ * to find who tries to free a free area
+ */
+void XfreeTrap(void)
+{
+}
+
+void *
+Xalloc (unsigned long amount)
+{
+ register unsigned long *ptr;
+ int indx;
+
+ /* sanity checks */
+
+ /* zero size requested */
+ if (amount == 0) {
+ LOG_ALLOC("Xalloc=0", amount, 0);
+ return NULL;
+ }
+ /* negative size (or size > 2GB) - what do we do? */
+ if ((long)amount < 0) {
+ /* Diagnostic */
+#ifdef FATALERRORS
+ FatalError("Xalloc: Xalloc(<0)\n");
+#else
+ ErrorF("Xalloc warning: Xalloc(<0) ignored..\n");
+#endif
+ LOG_ALLOC("Xalloc<0", amount, 0);
+ return NULL;
+ }
+
+ /* alignment check */
+#if defined(__alpha__) || defined(__alpha) || \
+ defined(__sparc__) || \
+ defined(__mips__) || \
+ defined(__powerpc__) || \
+ defined(__arm32__) || \
+ defined(__ia64__) || defined(ia64) || \
+ defined(__s390x__) || defined(__s390__)
+ amount = (amount + (sizeof(long)-1)) & ~(sizeof(long)-1);
+#endif
+
+ if (amount <= MAX_SMALL) {
+ /*
+ * small block
+ */
+ /* pick a ready to use small chunk */
+ indx = (amount-1) / SIZE_STEPS;
+ ptr = free_lists[indx];
+ if (NULL == ptr) {
+ /* list empty - get 20 or 40 more */
+ /* amount = size rounded up */
+ amount = (indx+1) * SIZE_STEPS;
+ ptr = (unsigned long *)calloc(1,(amount+SIZE_HEADER+TAIL_SIZE)
+ * (amount<100 ? 40 : 20));
+ if (NULL!=ptr) {
+ int i;
+ unsigned long *p1, *p2;
+ p1 = 0;
+ p2 = (unsigned long *)((char *)ptr + SIZE_HEADER);
+ for (i=0; i<(amount<100 ? 40 : 20); i++) {
+ p1 = p2;
+ p1[-2] = amount;
+#ifdef XALLOC_DEBUG
+ p1[-1] = MAGIC_FREE;
+#endif /* XALLOC_DEBUG */
+#ifdef SIZE_TAIL
+ *(unsigned long *)((unsigned char *)p1 + amount) = MAGIC2;
+#endif /* SIZE_TAIL */
+ p2 = (unsigned long *)((char *)p1 + SIZE_HEADER + amount + TAIL_SIZE);
+ *(unsigned long **)p1 = p2;
+ }
+ /* last one has no next one */
+ *(unsigned long **)p1 = NULL;
+ /* put the second in the list */
+ free_lists[indx] = (unsigned long *)((char *)ptr + SIZE_HEADER + amount + TAIL_SIZE + SIZE_HEADER);
+ /* take the fist one */
+ ptr = (unsigned long *)((char *)ptr + SIZE_HEADER);
+ LOG_ALLOC("Xalloc-S", amount, ptr);
+ ptr[-1] = MAGIC;
+ return (void *)ptr;
+ } /* else fall through to 'Out of memory' */
+ } else {
+ /* take that piece of mem out of the list */
+ free_lists[indx] = *((unsigned long **)ptr);
+ /* already has size (and evtl. magic) filled in */
+#ifdef XALLOC_DEBUG
+ ptr[-1] = MAGIC;
+#endif /* XALLOC_DEBUG */
+ LOG_ALLOC("Xalloc-S", amount, ptr);
+ return (void *)ptr;
+ }
+
+#if defined(HAS_MMAP_ANON) || defined(MMAP_DEV_ZERO)
+ } else if (amount >= MIN_LARGE) {
+ /*
+ * large block
+ */
+ /* mmapped malloc */
+ /* round up amount */
+ amount += SIZE_HEADER + TAIL_SIZE;
+ /* round up brutto amount to a multiple of the page size */
+ amount = (amount + pagesize-1) & ~(pagesize-1);
+#ifdef MMAP_DEV_ZERO
+ ptr = (unsigned long *)mmap((caddr_t)0,
+ (size_t)amount,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE,
+ devzerofd,
+ (off_t)0);
+#else
+ ptr = (unsigned long *)mmap((caddr_t)0,
+ (size_t)amount,
+ PROT_READ | PROT_WRITE,
+ MAP_ANON | MAP_PRIVATE,
+ -1,
+ (off_t)0);
+#endif
+ if (-1!=(long)ptr) {
+ ptr[0] = amount - SIZE_HEADER - TAIL_SIZE;
+#ifdef XALLOC_DEBUG
+ ptr[1] = MAGIC;
+#endif /* XALLOC_DEBUG */
+#ifdef SIZE_TAIL
+ ((unsigned long *)((char *)ptr + amount - TAIL_SIZE))[0] = MAGIC2;
+#endif /* SIZE_TAIL */
+ ptr = (unsigned long *)((char *)ptr + SIZE_HEADER);
+ LOG_ALLOC("Xalloc-L", amount, ptr);
+ return (void *)ptr;
+ } /* else fall through to 'Out of memory' */
+#endif /* HAS_MMAP_ANON || MMAP_DEV_ZERO */
+ } else {
+ /*
+ * medium sized block
+ */
+ /* 'normal' malloc() */
+ ptr=(unsigned long *)calloc(1,amount+SIZE_HEADER+TAIL_SIZE);
+ if (ptr != (unsigned long *)NULL) {
+ ptr[0] = amount;
+#ifdef XALLOC_DEBUG
+ ptr[1] = MAGIC;
+#endif /* XALLOC_DEBUG */
+#ifdef SIZE_TAIL
+ *(unsigned long *)((char *)ptr + amount + SIZE_HEADER) = MAGIC2;
+#endif /* SIZE_TAIL */
+ ptr = (unsigned long *)((char *)ptr + SIZE_HEADER);
+ LOG_ALLOC("Xalloc-M", amount, ptr);
+ return (void *)ptr;
+ }
+ }
+ if (Must_have_memory)
+ FatalError("Out of memory");
+ LOG_ALLOC("Xalloc-oom", amount, 0);
+ return NULL;
+}
+
+/*****************
+ * XNFalloc
+ * "no failure" realloc, alternate interface to Xalloc w/o Must_have_memory
+ *****************/
+
+pointer
+XNFalloc (unsigned long amount)
+{
+ register pointer ptr;
+
+ /* zero size requested */
+ if (amount == 0) {
+ LOG_ALLOC("XNFalloc=0", amount, 0);
+ return NULL;
+ }
+ /* negative size (or size > 2GB) - what do we do? */
+ if ((long)amount < 0) {
+ /* Diagnostic */
+#ifdef FATALERRORS
+ FatalError("Xalloc: XNFalloc(<0)\n");
+#else
+ ErrorF("Xalloc warning: XNFalloc(<0) ignored..\n");
+#endif
+ LOG_ALLOC("XNFalloc<0", amount, 0);
+ return (unsigned long *)NULL;
+ }
+ ptr = Xalloc(amount);
+ if (!ptr)
+ {
+ FatalError("Out of memory");
+ }
+ return ptr;
+}
+
+/*****************
+ * Xcalloc
+ *****************/
+
+pointer
+Xcalloc (unsigned long amount)
+{
+ pointer ret;
+
+ ret = Xalloc (amount);
+ if (ret != 0
+#if defined(HAS_MMAP_ANON) || defined(MMAP_DEV_ZERO)
+ && (amount < MIN_LARGE) /* mmaped anonymous mem is already cleared */
+#endif
+ )
+ bzero ((char *) ret, (int) amount);
+ return ret;
+}
+
+/*****************
+ * XNFcalloc
+ *****************/
+void *
+XNFcalloc (unsigned long amount)
+{
+ pointer ret;
+
+ ret = XNFalloc (amount);
+ if (ret != 0
+#if defined(HAS_MMAP_ANON) || defined(MMAP_DEV_ZERO)
+ && (amount < MIN_LARGE) /* mmaped anonymous mem is already cleared */
+#endif
+ )
+ bzero ((char *) ret, (int) amount);
+ return ret;
+}
+
+/*****************
+ * Xrealloc
+ *****************/
+
+void *
+Xrealloc (pointer ptr, unsigned long amount)
+{
+ register unsigned long *new_ptr;
+
+ /* zero size requested */
+ if (amount == 0) {
+ if (ptr)
+ Xfree(ptr);
+ LOG_REALLOC("Xrealloc=0", ptr, amount, 0);
+ return NULL;
+ }
+ /* negative size (or size > 2GB) - what do we do? */
+ if ((long)amount < 0) {
+ /* Diagnostic */
+#ifdef FATALERRORS
+ FatalError("Xalloc: Xrealloc(<0)\n");
+#else
+ ErrorF("Xalloc warning: Xrealloc(<0) ignored..\n");
+#endif
+ if (ptr)
+ Xfree(ptr); /* ?? */
+ LOG_REALLOC("Xrealloc<0", ptr, amount, 0);
+ return NULL;
+ }
+
+ new_ptr = Xalloc(amount);
+ if ( (new_ptr) && (ptr) ) {
+ unsigned long old_size;
+ old_size = ((unsigned long *)ptr)[-2];
+#ifdef XALLOC_DEBUG
+ if (MAGIC != ((unsigned long *)ptr)[-1]) {
+ if (MAGIC_FREE == ((unsigned long *)ptr)[-1]) {
+#ifdef FATALERRORS
+ XfreeTrap();
+ FatalError("Xalloc error: range already freed in Xrealloc() :-(\n");
+#else
+ ErrorF("Xalloc error: range already freed in Xrealloc() :-(\a\n");
+ sleep(5);
+ XfreeTrap();
+#endif
+ LOG_REALLOC("Xalloc error: ranged already freed in Xrealloc() :-(",
+ ptr, amount, 0);
+ return NULL;
+ }
+#ifdef FATALERRORS
+ XfreeTrap();
+ FatalError("Xalloc error: header corrupt in Xrealloc() :-(\n");
+#else
+ ErrorF("Xalloc error: header corrupt in Xrealloc() :-(\n");
+ XfreeTrap();
+#endif
+ LOG_REALLOC("Xalloc error: header corrupt in Xrealloc() :-(",
+ ptr, amount, 0);
+ return NULL;
+ }
+#endif /* XALLOC_DEBUG */
+ /* copy min(old size, new size) */
+ memcpy((char *)new_ptr, (char *)ptr, (amount < old_size ? amount : old_size));
+ }
+ if (ptr)
+ Xfree(ptr);
+ if (new_ptr) {
+ LOG_REALLOC("Xrealloc", ptr, amount, new_ptr);
+ return (void *)new_ptr;
+ }
+ if (Must_have_memory)
+ FatalError("Out of memory");
+ LOG_REALLOC("Xrealloc", ptr, amount, 0);
+ return NULL;
+}
+
+/*****************
+ * XNFrealloc
+ * "no failure" realloc, alternate interface to Xrealloc w/o Must_have_memory
+ *****************/
+
+void *
+XNFrealloc (pointer ptr, unsigned long amount)
+{
+ if (( ptr = (pointer)Xrealloc( ptr, amount ) ) == NULL)
+ {
+ FatalError( "Out of memory" );
+ }
+ return ptr;
+}
+
+/*****************
+ * Xfree
+ * calls free
+ *****************/
+
+void
+Xfree(pointer ptr)
+{
+ unsigned long size;
+ unsigned long *pheader;
+
+ /* free(NULL) IS valid :-( - and widely used throughout the server.. */
+ if (!ptr)
+ return;
+
+ pheader = (unsigned long *)((char *)ptr - SIZE_HEADER);
+#ifdef XALLOC_DEBUG
+ if (MAGIC != pheader[1]) {
+ /* Diagnostic */
+ if (MAGIC_FREE == pheader[1]) {
+#ifdef FATALERRORS
+ XfreeTrap();
+ FatalError("Xalloc error: range already freed in Xrealloc() :-(\n");
+#else
+ ErrorF("Xalloc error: range already freed in Xrealloc() :-(\a\n");
+ sleep(5);
+ XfreeTrap();
+#endif
+ LOG_FREE("Xalloc error: ranged already freed in Xrealloc() :-(", ptr);
+ return;
+ }
+#ifdef FATALERRORS
+ XfreeTrap();
+ FatalError("Xalloc error: Header corrupt in Xfree() :-(\n");
+#else
+ ErrorF("Xalloc error: Header corrupt in Xfree() :-(\n");
+ XfreeTrap();
+#endif
+ LOG_FREE("Xalloc error: Header corrupt in Xfree() :-(", ptr);
+ return;
+ }
+#endif /* XALLOC_DEBUG */
+
+ size = pheader[0];
+ if (size <= MAX_SMALL) {
+ int indx;
+ /*
+ * small block
+ */
+#ifdef SIZE_TAIL
+ if (MAGIC2 != *(unsigned long *)((char *)ptr + size)) {
+ /* Diagnostic */
+#ifdef FATALERRORS
+ XfreeTrap();
+ FatalError("Xalloc error: Tail corrupt in Xfree() for small block (adr=0x%x, val=0x%x)\n",(char *)ptr + size,*(unsigned long *)((char *)ptr + size));
+#else
+ ErrorF("Xalloc error: Tail corrupt in Xfree() for small block (adr=0x%x, val=0x%x)\n",(char *)ptr + size,*(unsigned long *)((char *)ptr + size));
+ XfreeTrap();
+#endif
+ LOG_FREE("Xalloc error: Tail corrupt in Xfree() for small block", ptr);
+ return;
+ }
+#endif /* SIZE_TAIL */
+
+#ifdef XFREE_ERASES
+ memset(ptr,0xF0,size);
+#endif /* XFREE_ERASES */
+#ifdef XALLOC_DEBUG
+ pheader[1] = MAGIC_FREE;
+#endif
+ /* put this small block at the head of the list */
+ indx = (size-1) / SIZE_STEPS;
+ *(unsigned long **)(ptr) = free_lists[indx];
+ free_lists[indx] = (unsigned long *)ptr;
+ LOG_FREE("Xfree", ptr);
+ return;
+
+#if defined(HAS_MMAP_ANON) || defined(MMAP_DEV_ZERO)
+ } else if (size >= MIN_LARGE) {
+ /*
+ * large block
+ */
+#ifdef SIZE_TAIL
+ if (MAGIC2 != ((unsigned long *)((char *)ptr + size))[0]) {
+ /* Diagnostic */
+#ifdef FATALERRORS
+ XfreeTrap();
+ FatalError("Xalloc error: Tail corrupt in Xfree() for big block (adr=0x%x, val=0x%x)\n",(char *)ptr+size,((unsigned long *)((char *)ptr + size))[0]);
+#else
+ ErrorF("Xalloc error: Tail corrupt in Xfree() for big block (adr=0x%x, val=0x%x)\n",(char *)ptr+size,((unsigned long *)((char *)ptr + size))[0]);
+ XfreeTrap();
+#endif
+ LOG_FREE("Xalloc error: Tail corrupt in Xfree() for big block", ptr);
+ return;
+ }
+ size += SIZE_TAIL;
+#endif /* SIZE_TAIL */
+
+ LOG_FREE("Xfree", ptr);
+ size += SIZE_HEADER;
+ munmap((caddr_t)pheader, (size_t)size);
+ /* no need to clear - mem is inaccessible after munmap.. */
+#endif /* HAS_MMAP_ANON */
+
+ } else {
+ /*
+ * medium sized block
+ */
+#ifdef SIZE_TAIL
+ if (MAGIC2 != *(unsigned long *)((char *)ptr + size)) {
+ /* Diagnostic */
+#ifdef FATALERRORS
+ XfreeTrap();
+ FatalError("Xalloc error: Tail corrupt in Xfree() for medium block (adr=0x%x, val=0x%x)\n",(char *)ptr + size,*(unsigned long *)((char *)ptr + size));
+#else
+ ErrorF("Xalloc error: Tail corrupt in Xfree() for medium block (adr=0x%x, val=0x%x)\n",(char *)ptr + size,*(unsigned long *)((char *)ptr + size));
+ XfreeTrap();
+#endif
+ LOG_FREE("Xalloc error: Tail corrupt in Xfree() for medium block", ptr);
+ return;
+ }
+#endif /* SIZE_TAIL */
+
+#ifdef XFREE_ERASES
+ memset(pheader,0xF0,size+SIZE_HEADER);
+#endif /* XFREE_ERASES */
+#ifdef XALLOC_DEBUG
+ pheader[1] = MAGIC_FREE;
+#endif
+
+ LOG_FREE("Xfree", ptr);
+ free((char *)pheader);
+ }
+}
+
+void
+OsInitAllocator (void)
+{
+ static Bool beenhere = FALSE;
+
+ if (beenhere)
+ return;
+ beenhere = TRUE;
+
+#if defined(HAS_MMAP_ANON) || defined (MMAP_DEV_ZERO)
+ pagesize = -1;
+#if defined(_SC_PAGESIZE) || defined(HAS_SC_PAGESIZE)
+ pagesize = sysconf(_SC_PAGESIZE);
+#endif
+#ifdef _SC_PAGE_SIZE
+ if (pagesize == -1)
+ pagesize = sysconf(_SC_PAGE_SIZE);
+#endif
+#ifdef HAS_GETPAGESIZE
+ if (pagesize == -1)
+ pagesize = getpagesize();
+#endif
+#ifdef PAGE_SIZE
+ if (pagesize == -1)
+ pagesize = PAGE_SIZE;
+#endif
+ if (pagesize == -1)
+ FatalError("OsInitAllocator: Cannot determine page size\n");
+#endif
+
+ /* set up linked lists of free blocks */
+ bzero ((char *) free_lists, MAX_SMALL/SIZE_STEPS*sizeof(unsigned long *));
+
+#ifdef MMAP_DEV_ZERO
+ /* open /dev/zero on systems that have mmap, but not MAP_ANON */
+ if (devzerofd < 0) {
+ if ((devzerofd = open("/dev/zero", O_RDWR, 0)) < 0)
+ FatalError("OsInitAllocator: Cannot open /dev/zero (errno=%d)\n",
+ errno);
+ }
+#endif
+
+#ifdef XALLOC_LOG
+ /* reset the log file to zero length */
+ {
+ FILE *f;
+ f = fopen(XALLOC_LOG_FILE, "w");
+ if (NULL!=f)
+ fclose(f);
+ }
+#endif
+}
+
+#else /* !INTERNAL_MALLOC */
+/* This is to avoid an empty .o */
+static int no_internal_xalloc;
+#endif /* INTERNAL_MALLOC */