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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /nsprpub/pr/src/malloc/prmalloc.c
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
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Add m-esr52 at 52.6.0
Diffstat (limited to 'nsprpub/pr/src/malloc/prmalloc.c')
-rw-r--r--nsprpub/pr/src/malloc/prmalloc.c1142
1 files changed, 1142 insertions, 0 deletions
diff --git a/nsprpub/pr/src/malloc/prmalloc.c b/nsprpub/pr/src/malloc/prmalloc.c
new file mode 100644
index 000000000..174d0daf7
--- /dev/null
+++ b/nsprpub/pr/src/malloc/prmalloc.c
@@ -0,0 +1,1142 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "primpl.h"
+
+/*
+** We override malloc etc. on any platform which has preemption +
+** nspr20 user level threads. When we're debugging, we can make our
+** version of malloc fail occasionally.
+*/
+#ifdef _PR_OVERRIDE_MALLOC
+
+/*
+** Thread safe version of malloc, calloc, realloc, free
+*/
+#include <stdarg.h>
+
+#ifdef DEBUG
+#define SANITY
+#define EXTRA_SANITY
+#else
+#undef SANITY
+#undef EXTRA_SANITY
+#endif
+
+/* Forward decls */
+void *_PR_UnlockedMalloc(size_t size);
+void _PR_UnlockedFree(void *ptr);
+void *_PR_UnlockedRealloc(void *ptr, size_t size);
+void *_PR_UnlockedCalloc(size_t n, size_t elsize);
+
+/************************************************************************/
+
+/*
+ * ----------------------------------------------------------------------------
+ * "THE BEER-WARE LICENSE" (Revision 42):
+ * <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you
+ * can do whatever you want with this stuff. If we meet some day, and you think
+ * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
+ * ----------------------------------------------------------------------------
+ *
+ */
+
+/*
+ * Defining SANITY will enable some checks which will tell you if the users
+ * program did botch something
+ */
+
+/*
+ * Defining EXTRA_SANITY will enable some checks which are mostly related
+ * to internal conditions in malloc.c
+ */
+
+/*
+ * Very verbose progress on stdout...
+ */
+#if 0
+# define TRACE(foo) printf foo
+static int malloc_event;
+#else
+# define TRACE(foo)
+#endif
+
+/* XXX Pick a number, any number */
+# define malloc_pagesize 4096UL
+# define malloc_pageshift 12UL
+
+#ifdef XP_UNIX
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#endif
+
+/*
+ * This structure describes a page's worth of chunks.
+ */
+
+struct pginfo {
+ struct pginfo *next; /* next on the free list */
+ char *page; /* Pointer to the page */
+ u_short size; /* size of this page's chunks */
+ u_short shift; /* How far to shift for this size chunks */
+ u_short free; /* How many free chunks */
+ u_short total; /* How many chunk */
+ u_long bits[1]; /* Which chunks are free */
+};
+
+struct pgfree {
+ struct pgfree *next; /* next run of free pages */
+ struct pgfree *prev; /* prev run of free pages */
+ char *page; /* pointer to free pages */
+ char *end; /* pointer to end of free pages */
+ u_long size; /* number of bytes free */
+};
+
+/*
+ * How many bits per u_long in the bitmap.
+ * Change only if not 8 bits/byte
+ */
+#define MALLOC_BITS (8*sizeof(u_long))
+
+/*
+ * Magic values to put in the page_directory
+ */
+#define MALLOC_NOT_MINE ((struct pginfo*) 0)
+#define MALLOC_FREE ((struct pginfo*) 1)
+#define MALLOC_FIRST ((struct pginfo*) 2)
+#define MALLOC_FOLLOW ((struct pginfo*) 3)
+#define MALLOC_MAGIC ((struct pginfo*) 4)
+
+/*
+ * Set to one when malloc_init has been called
+ */
+static unsigned initialized;
+
+/*
+ * The size of a page.
+ * Must be a integral multiplum of the granularity of mmap(2).
+ * Your toes will curl if it isn't a power of two
+ */
+#define malloc_pagemask ((malloc_pagesize)-1)
+
+/*
+ * The size of the largest chunk.
+ * Half a page.
+ */
+#define malloc_maxsize ((malloc_pagesize)>>1)
+
+/*
+ * malloc_pagesize == 1 << malloc_pageshift
+ */
+#ifndef malloc_pageshift
+static unsigned malloc_pageshift;
+#endif /* malloc_pageshift */
+
+/*
+ * The smallest allocation we bother about.
+ * Must be power of two
+ */
+#ifndef malloc_minsize
+static unsigned malloc_minsize;
+#endif /* malloc_minsize */
+
+/*
+ * The largest chunk we care about.
+ * Must be smaller than pagesize
+ * Must be power of two
+ */
+#ifndef malloc_maxsize
+static unsigned malloc_maxsize;
+#endif /* malloc_maxsize */
+
+#ifndef malloc_cache
+static unsigned malloc_cache;
+#endif /* malloc_cache */
+
+/*
+ * The offset from pagenumber to index into the page directory
+ */
+static u_long malloc_origo;
+
+/*
+ * The last index in the page directory we care about
+ */
+static u_long last_index;
+
+/*
+ * Pointer to page directory.
+ * Allocated "as if with" malloc
+ */
+static struct pginfo **page_dir;
+
+/*
+ * How many slots in the page directory
+ */
+static unsigned malloc_ninfo;
+
+/*
+ * Free pages line up here
+ */
+static struct pgfree free_list;
+
+/*
+ * Abort() if we fail to get VM ?
+ */
+static int malloc_abort;
+
+#ifdef SANITY
+/*
+ * Are we trying to die ?
+ */
+static int suicide;
+#endif
+
+/*
+ * dump statistics
+ */
+static int malloc_stats;
+
+/*
+ * always realloc ?
+ */
+static int malloc_realloc;
+
+/*
+ * my last break.
+ */
+static void *malloc_brk;
+
+/*
+ * one location cache for free-list holders
+ */
+static struct pgfree *px;
+
+static int set_pgdir(void *ptr, struct pginfo *info);
+static int extend_page_directory(u_long index);
+
+#ifdef SANITY
+void
+malloc_dump(FILE *fd)
+{
+ struct pginfo **pd;
+ struct pgfree *pf;
+ int j;
+
+ pd = page_dir;
+
+ /* print out all the pages */
+ for(j=0;j<=last_index;j++) {
+ fprintf(fd,"%08lx %5d ",(j+malloc_origo) << malloc_pageshift,j);
+ if (pd[j] == MALLOC_NOT_MINE) {
+ for(j++;j<=last_index && pd[j] == MALLOC_NOT_MINE;j++)
+ ;
+ j--;
+ fprintf(fd,".. %5d not mine\n", j);
+ } else if (pd[j] == MALLOC_FREE) {
+ for(j++;j<=last_index && pd[j] == MALLOC_FREE;j++)
+ ;
+ j--;
+ fprintf(fd,".. %5d free\n", j);
+ } else if (pd[j] == MALLOC_FIRST) {
+ for(j++;j<=last_index && pd[j] == MALLOC_FOLLOW;j++)
+ ;
+ j--;
+ fprintf(fd,".. %5d in use\n", j);
+ } else if (pd[j] < MALLOC_MAGIC) {
+ fprintf(fd,"(%p)\n", pd[j]);
+ } else {
+ fprintf(fd,"%p %d (of %d) x %d @ %p --> %p\n",
+ pd[j],pd[j]->free, pd[j]->total,
+ pd[j]->size, pd[j]->page, pd[j]->next);
+ }
+ }
+
+ for(pf=free_list.next; pf; pf=pf->next) {
+ fprintf(fd,"Free: @%p [%p...%p[ %ld ->%p <-%p\n",
+ pf,pf->page,pf->end,pf->size,pf->prev,pf->next);
+ if (pf == pf->next) {
+ fprintf(fd,"Free_list loops.\n");
+ break;
+ }
+ }
+
+ /* print out various info */
+ fprintf(fd,"Minsize\t%d\n",malloc_minsize);
+ fprintf(fd,"Maxsize\t%ld\n",malloc_maxsize);
+ fprintf(fd,"Pagesize\t%ld\n",malloc_pagesize);
+ fprintf(fd,"Pageshift\t%ld\n",malloc_pageshift);
+ fprintf(fd,"FirstPage\t%ld\n",malloc_origo);
+ fprintf(fd,"LastPage\t%ld %lx\n",last_index+malloc_pageshift,
+ (last_index + malloc_pageshift) << malloc_pageshift);
+ fprintf(fd,"Break\t%ld\n",(u_long)sbrk(0) >> malloc_pageshift);
+}
+
+static void wrterror(char *fmt, ...)
+{
+ char *q = "malloc() error: ";
+ char buf[100];
+ va_list ap;
+
+ suicide = 1;
+
+ va_start(ap, fmt);
+ PR_vsnprintf(buf, sizeof(buf), fmt, ap);
+ va_end(ap);
+ fputs(q, stderr);
+ fputs(buf, stderr);
+
+ malloc_dump(stderr);
+ PR_Abort();
+}
+
+static void wrtwarning(char *fmt, ...)
+{
+ char *q = "malloc() warning: ";
+ char buf[100];
+ va_list ap;
+
+ va_start(ap, fmt);
+ PR_vsnprintf(buf, sizeof(buf), fmt, ap);
+ va_end(ap);
+ fputs(q, stderr);
+ fputs(buf, stderr);
+}
+#endif /* SANITY */
+
+
+/*
+ * Allocate a number of pages from the OS
+ */
+static caddr_t
+map_pages(int pages, int update)
+{
+ caddr_t result,tail;
+
+ result = ((caddr_t)sbrk(0)) + malloc_pagemask - 1;
+ result = (caddr_t) ((u_long)result & ~malloc_pagemask);
+ tail = result + (pages << malloc_pageshift);
+ if (!brk(tail)) {
+ last_index = ((u_long)tail >> malloc_pageshift) - malloc_origo -1;
+ malloc_brk = tail;
+ TRACE(("%6d S %p .. %p\n",malloc_event++, result, tail));
+ if (!update || last_index < malloc_ninfo ||
+ extend_page_directory(last_index))
+ return result;
+ }
+ TRACE(("%6d s %d %p %d\n",malloc_event++,pages,sbrk(0),errno));
+#ifdef EXTRA_SANITY
+ wrterror("map_pages fails\n");
+#endif
+ return 0;
+}
+
+#define set_bit(_pi,_bit) \
+ (_pi)->bits[(_bit)/MALLOC_BITS] |= 1L<<((_bit)%MALLOC_BITS)
+
+#define clr_bit(_pi,_bit) \
+ (_pi)->bits[(_bit)/MALLOC_BITS] &= ~(1L<<((_bit)%MALLOC_BITS));
+
+#define tst_bit(_pi,_bit) \
+ ((_pi)->bits[(_bit)/MALLOC_BITS] & (1L<<((_bit)%MALLOC_BITS)))
+
+/*
+ * Extend page directory
+ */
+static int
+extend_page_directory(u_long index)
+{
+ struct pginfo **young, **old;
+ int i;
+
+ TRACE(("%6d E %lu\n",malloc_event++,index));
+
+ /* Make it this many pages */
+ i = index * sizeof *page_dir;
+ i /= malloc_pagesize;
+ i += 2;
+
+ /* Get new pages, if you used this much mem you don't care :-) */
+ young = (struct pginfo**) map_pages(i,0);
+ if (!young)
+ return 0;
+
+ /* Copy the old stuff */
+ memset(young, 0, i * malloc_pagesize);
+ memcpy(young, page_dir,
+ malloc_ninfo * sizeof *page_dir);
+
+ /* register the new size */
+ malloc_ninfo = i * malloc_pagesize / sizeof *page_dir;
+
+ /* swap the pointers */
+ old = page_dir;
+ page_dir = young;
+
+ /* Mark the pages */
+ index = ((u_long)young >> malloc_pageshift) - malloc_origo;
+ page_dir[index] = MALLOC_FIRST;
+ while (--i) {
+ page_dir[++index] = MALLOC_FOLLOW;
+ }
+
+ /* Now free the old stuff */
+ _PR_UnlockedFree(old);
+ return 1;
+}
+
+/*
+ * Set entry in page directory.
+ * Extend page directory if need be.
+ */
+static int
+set_pgdir(void *ptr, struct pginfo *info)
+{
+ u_long index = ((u_long)ptr >> malloc_pageshift) - malloc_origo;
+
+ if (index >= malloc_ninfo && !extend_page_directory(index))
+ return 0;
+ page_dir[index] = info;
+ return 1;
+}
+
+/*
+ * Initialize the world
+ */
+static void
+malloc_init (void)
+{
+ int i;
+ char *p;
+
+ TRACE(("%6d I\n",malloc_event++));
+#ifdef DEBUG
+ for (p=getenv("MALLOC_OPTIONS"); p && *p; p++) {
+ switch (*p) {
+ case 'a': malloc_abort = 0; break;
+ case 'A': malloc_abort = 1; break;
+ case 'd': malloc_stats = 0; break;
+ case 'D': malloc_stats = 1; break;
+ case 'r': malloc_realloc = 0; break;
+ case 'R': malloc_realloc = 1; break;
+ default:
+ wrtwarning("Unknown chars in MALLOC_OPTIONS\n");
+ break;
+ }
+ }
+#endif
+
+#ifndef malloc_pagesize
+ /* determine our pagesize */
+ malloc_pagesize = getpagesize();
+#endif /* malloc_pagesize */
+
+#ifndef malloc_pageshift
+ /* determine how much we shift by to get there */
+ for (i = malloc_pagesize; i > 1; i >>= 1)
+ malloc_pageshift++;
+#endif /* malloc_pageshift */
+
+#ifndef malloc_cache
+ malloc_cache = 50 << malloc_pageshift;
+#endif /* malloc_cache */
+
+#ifndef malloc_minsize
+ /*
+ * find the smallest size allocation we will bother about.
+ * this is determined as the smallest allocation that can hold
+ * it's own pginfo;
+ */
+ i = 2;
+ for(;;) {
+ int j;
+
+ /* Figure out the size of the bits */
+ j = malloc_pagesize/i;
+ j /= 8;
+ if (j < sizeof(u_long))
+ j = sizeof (u_long);
+ if (sizeof(struct pginfo) + j - sizeof (u_long) <= i)
+ break;
+ i += i;
+ }
+ malloc_minsize = i;
+#endif /* malloc_minsize */
+
+
+ /* Allocate one page for the page directory */
+ page_dir = (struct pginfo **) map_pages(1,0);
+#ifdef SANITY
+ if (!page_dir)
+ wrterror("fatal: my first mmap failed. (check limits ?)\n");
+#endif
+
+ /*
+ * We need a maximum of malloc_pageshift buckets, steal these from the
+ * front of the page_directory;
+ */
+ malloc_origo = (u_long) page_dir >> malloc_pageshift;
+ malloc_origo -= malloc_pageshift;
+
+ /* Clear it */
+ memset(page_dir,0,malloc_pagesize);
+
+ /* Find out how much it tells us */
+ malloc_ninfo = malloc_pagesize / sizeof *page_dir;
+
+ /* Plug the page directory into itself */
+ i = set_pgdir(page_dir,MALLOC_FIRST);
+#ifdef SANITY
+ if (!i)
+ wrterror("fatal: couldn't set myself in the page directory\n");
+#endif
+
+ /* Been here, done that */
+ initialized++;
+}
+
+/*
+ * Allocate a number of complete pages
+ */
+static void *malloc_pages(size_t size)
+{
+ void *p,*delay_free = 0;
+ int i;
+ struct pgfree *pf;
+ u_long index;
+
+ /* How many pages ? */
+ size += (malloc_pagesize-1);
+ size &= ~malloc_pagemask;
+
+ p = 0;
+ /* Look for free pages before asking for more */
+ for(pf = free_list.next; pf; pf = pf->next) {
+#ifdef EXTRA_SANITY
+ if (pf->page == pf->end)
+ wrterror("zero entry on free_list\n");
+ if (pf->page > pf->end) {
+ TRACE(("%6d !s %p %p %p <%d>\n",malloc_event++,
+ pf,pf->page,pf->end,__LINE__));
+ wrterror("sick entry on free_list\n");
+ }
+ if ((void*)pf->page >= (void*)sbrk(0))
+ wrterror("entry on free_list past brk\n");
+ if (page_dir[((u_long)pf->page >> malloc_pageshift) - malloc_origo]
+ != MALLOC_FREE) {
+ TRACE(("%6d !f %p %p %p <%d>\n",malloc_event++,
+ pf,pf->page,pf->end,__LINE__));
+ wrterror("non-free first page on free-list\n");
+ }
+ if (page_dir[((u_long)pf->end >> malloc_pageshift) - 1 - malloc_origo]
+ != MALLOC_FREE)
+ wrterror("non-free last page on free-list\n");
+#endif /* EXTRA_SANITY */
+ if (pf->size < size)
+ continue;
+ else if (pf->size == size) {
+ p = pf->page;
+ if (pf->next)
+ pf->next->prev = pf->prev;
+ pf->prev->next = pf->next;
+ delay_free = pf;
+ break;
+ } else {
+ p = pf->page;
+ pf->page += size;
+ pf->size -= size;
+ break;
+ }
+ }
+#ifdef EXTRA_SANITY
+ if (p && page_dir[((u_long)p >> malloc_pageshift) - malloc_origo]
+ != MALLOC_FREE) {
+ wrterror("allocated non-free page on free-list\n");
+ }
+#endif /* EXTRA_SANITY */
+
+ size >>= malloc_pageshift;
+
+ /* Map new pages */
+ if (!p)
+ p = map_pages(size,1);
+
+ if (p) {
+ /* Mark the pages in the directory */
+ index = ((u_long)p >> malloc_pageshift) - malloc_origo;
+ page_dir[index] = MALLOC_FIRST;
+ for (i=1;i<size;i++)
+ page_dir[index+i] = MALLOC_FOLLOW;
+ }
+ if (delay_free) {
+ if (!px)
+ px = (struct pgfree*)delay_free;
+ else
+ _PR_UnlockedFree(delay_free);
+ }
+ return p;
+}
+
+/*
+ * Allocate a page of fragments
+ */
+
+static int
+malloc_make_chunks(int bits)
+{
+ struct pginfo *bp;
+ void *pp;
+ int i,k,l;
+
+ /* Allocate a new bucket */
+ pp = malloc_pages(malloc_pagesize);
+ if (!pp)
+ return 0;
+ l = sizeof *bp - sizeof(u_long);
+ l += sizeof(u_long) *
+ (((malloc_pagesize >> bits)+MALLOC_BITS-1) / MALLOC_BITS);
+ if ((1<<(bits)) <= l+l) {
+ bp = (struct pginfo *)pp;
+ } else {
+ bp = (struct pginfo *)_PR_UnlockedMalloc(l);
+ }
+ if (!bp)
+ return 0;
+ bp->size = (1<<bits);
+ bp->shift = bits;
+ bp->total = bp->free = malloc_pagesize >> bits;
+ bp->next = page_dir[bits];
+ bp->page = (char*)pp;
+ i = set_pgdir(pp,bp);
+ if (!i)
+ return 0;
+
+ /* We can safely assume that there is nobody in this chain */
+ page_dir[bits] = bp;
+
+ /* set all valid bits in the bits */
+ k = bp->total;
+ i = 0;
+/*
+ for(;k-i >= MALLOC_BITS; i += MALLOC_BITS)
+ bp->bits[i / MALLOC_BITS] = ~0;
+*/
+ for(; i < k; i++)
+ set_bit(bp,i);
+
+ if (bp != pp)
+ return 1;
+
+ /* We may have used the first ones already */
+ for(i=0;l > 0;i++) {
+ clr_bit(bp,i);
+ bp->free--;
+ bp->total--;
+ l -= (1 << bits);
+ }
+ return 1;
+}
+
+/*
+ * Allocate a fragment
+ */
+static void *malloc_bytes(size_t size)
+{
+ size_t s;
+ int j;
+ struct pginfo *bp;
+ int k;
+ u_long *lp, bf;
+
+ /* Don't bother with anything less than this */
+ if (size < malloc_minsize) {
+ size = malloc_minsize;
+ }
+
+ /* Find the right bucket */
+ j = 1;
+ s = size - 1;
+ while (s >>= 1) {
+ j++;
+ }
+
+ /* If it's empty, make a page more of that size chunks */
+ if (!page_dir[j] && !malloc_make_chunks(j))
+ return 0;
+
+ /* Find first word of bitmap which isn't empty */
+ bp = page_dir[j];
+ for (lp = bp->bits; !*lp; lp++)
+ ;
+
+ /* Find that bit */
+ bf = *lp;
+ k = 0;
+ while ((bf & 1) == 0) {
+ bf >>= 1;
+ k++;
+ }
+
+ *lp ^= 1L<<k; /* clear it */
+ bp->free--;
+ if (!bp->free) {
+ page_dir[j] = bp->next;
+ bp->next = 0;
+ }
+ k += (lp - bp->bits)*MALLOC_BITS;
+ return bp->page + (k << bp->shift);
+}
+
+void *_PR_UnlockedMalloc(size_t size)
+{
+ void *result;
+
+ /* Round up to a multiple of 8 bytes */
+ if (size & 7) {
+ size = size + 8 - (size & 7);
+ }
+
+ if (!initialized)
+ malloc_init();
+
+#ifdef SANITY
+ if (suicide)
+ PR_Abort();
+#endif
+
+ if (size <= malloc_maxsize)
+ result = malloc_bytes(size);
+ else
+ result = malloc_pages(size);
+#ifdef SANITY
+ if (malloc_abort && !result)
+ wrterror("malloc() returns NULL\n");
+#endif
+ TRACE(("%6d M %p %d\n",malloc_event++,result,size));
+
+ return result;
+}
+
+void *_PR_UnlockedMemalign(size_t alignment, size_t size)
+{
+ void *result;
+
+ /*
+ * alignment has to be a power of 2
+ */
+
+ if ((size <= alignment) && (alignment <= malloc_maxsize))
+ size = alignment;
+ else
+ size += alignment - 1;
+
+ /* Round up to a multiple of 8 bytes */
+ if (size & 7) {
+ size = size + 8 - (size & 7);
+ }
+
+ if (!initialized)
+ malloc_init();
+
+#ifdef SANITY
+ if (suicide)
+ abort();
+#endif
+
+ if (size <= malloc_maxsize)
+ result = malloc_bytes(size);
+ else
+ result = malloc_pages(size);
+#ifdef SANITY
+ if (malloc_abort && !result)
+ wrterror("malloc() returns NULL\n");
+#endif
+ TRACE(("%6d A %p %d\n",malloc_event++,result,size));
+
+ if ((u_long)result & (alignment - 1))
+ return ((void *)(((u_long)result + alignment) & ~(alignment - 1)));
+ else
+ return result;
+}
+
+void *_PR_UnlockedCalloc(size_t n, size_t nelem)
+{
+ void *p;
+
+ /* Compute total size and then round up to a double word amount */
+ n *= nelem;
+ if (n & 7) {
+ n = n + 8 - (n & 7);
+ }
+
+ /* Get the memory */
+ p = _PR_UnlockedMalloc(n);
+ if (p) {
+ /* Zero it */
+ memset(p, 0, n);
+ }
+ return p;
+}
+
+/*
+ * Change an allocation's size
+ */
+void *_PR_UnlockedRealloc(void *ptr, size_t size)
+{
+ void *p;
+ u_long osize,page,index,tmp_index;
+ struct pginfo **mp;
+
+ if (!initialized)
+ malloc_init();
+
+#ifdef SANITY
+ if (suicide)
+ PR_Abort();
+#endif
+
+ /* used as free() */
+ TRACE(("%6d R %p %d\n",malloc_event++, ptr, size));
+ if (ptr && !size) {
+ _PR_UnlockedFree(ptr);
+ return _PR_UnlockedMalloc (1);
+ }
+
+ /* used as malloc() */
+ if (!ptr) {
+ p = _PR_UnlockedMalloc(size);
+ return p;
+ }
+
+ /* Find the page directory entry for the page in question */
+ page = (u_long)ptr >> malloc_pageshift;
+ index = page - malloc_origo;
+
+ /*
+ * check if memory was allocated by memalign
+ */
+ tmp_index = index;
+ while (page_dir[tmp_index] == MALLOC_FOLLOW)
+ tmp_index--;
+ if (tmp_index != index) {
+ /*
+ * memalign-allocated memory
+ */
+ index = tmp_index;
+ page = index + malloc_origo;
+ ptr = (void *) (page << malloc_pageshift);
+ }
+ TRACE(("%6d R2 %p %d\n",malloc_event++, ptr, size));
+
+ /* make sure it makes sense in some fashion */
+ if (index < malloc_pageshift || index > last_index) {
+#ifdef SANITY
+ wrtwarning("junk pointer passed to realloc()\n");
+#endif
+ return 0;
+ }
+
+ /* find the size of that allocation, and see if we need to relocate */
+ mp = &page_dir[index];
+ if (*mp == MALLOC_FIRST) {
+ osize = malloc_pagesize;
+ while (mp[1] == MALLOC_FOLLOW) {
+ osize += malloc_pagesize;
+ mp++;
+ }
+ if (!malloc_realloc &&
+ size < osize &&
+ size > malloc_maxsize &&
+ size > (osize - malloc_pagesize)) {
+ return ptr;
+ }
+ } else if (*mp >= MALLOC_MAGIC) {
+ osize = (*mp)->size;
+ if (!malloc_realloc &&
+ size < osize &&
+ (size > (*mp)->size/2 || (*mp)->size == malloc_minsize)) {
+ return ptr;
+ }
+ } else {
+#ifdef SANITY
+ wrterror("realloc() of wrong page.\n");
+#endif
+ }
+
+ /* try to reallocate */
+ p = _PR_UnlockedMalloc(size);
+
+ if (p) {
+ /* copy the lesser of the two sizes */
+ if (osize < size)
+ memcpy(p,ptr,osize);
+ else
+ memcpy(p,ptr,size);
+ _PR_UnlockedFree(ptr);
+ }
+#ifdef DEBUG
+ else if (malloc_abort)
+ wrterror("realloc() returns NULL\n");
+#endif
+
+ return p;
+}
+
+/*
+ * Free a sequence of pages
+ */
+
+static void
+free_pages(char *ptr, u_long page, int index, struct pginfo *info)
+{
+ int i;
+ struct pgfree *pf,*pt;
+ u_long l;
+ char *tail;
+
+ TRACE(("%6d FP %p %d\n",malloc_event++, ptr, page));
+ /* Is it free already ? */
+ if (info == MALLOC_FREE) {
+#ifdef SANITY
+ wrtwarning("freeing free page at %p.\n", ptr);
+#endif
+ return;
+ }
+
+#ifdef SANITY
+ /* Is it not the right place to begin ? */
+ if (info != MALLOC_FIRST)
+ wrterror("freeing wrong page.\n");
+
+ /* Is this really a pointer to a page ? */
+ if ((u_long)ptr & malloc_pagemask)
+ wrterror("freeing messed up page pointer.\n");
+#endif
+
+ /* Count how many pages it is anyway */
+ page_dir[index] = MALLOC_FREE;
+ for (i = 1; page_dir[index+i] == MALLOC_FOLLOW; i++)
+ page_dir[index + i] = MALLOC_FREE;
+
+ l = i << malloc_pageshift;
+
+ tail = ptr+l;
+
+ /* add to free-list */
+ if (!px)
+ px = (struct pgfree*)_PR_UnlockedMalloc(sizeof *pt);
+ /* XXX check success */
+ px->page = ptr;
+ px->end = tail;
+ px->size = l;
+ if (!free_list.next) {
+ px->next = free_list.next;
+ px->prev = &free_list;
+ free_list.next = px;
+ pf = px;
+ px = 0;
+ } else {
+ tail = ptr+l;
+ for(pf = free_list.next; pf->next && pf->end < ptr; pf = pf->next)
+ ;
+ for(; pf; pf = pf->next) {
+ if (pf->end == ptr ) {
+ /* append to entry */
+ pf->end += l;
+ pf->size += l;
+ if (pf->next && pf->end == pf->next->page ) {
+ pt = pf->next;
+ pf->end = pt->end;
+ pf->size += pt->size;
+ pf->next = pt->next;
+ if (pf->next)
+ pf->next->prev = pf;
+ _PR_UnlockedFree(pt);
+ }
+ } else if (pf->page == tail) {
+ /* prepend to entry */
+ pf->size += l;
+ pf->page = ptr;
+ } else if (pf->page > ptr) {
+ px->next = pf;
+ px->prev = pf->prev;
+ pf->prev = px;
+ px->prev->next = px;
+ pf = px;
+ px = 0;
+ } else if (!pf->next) {
+ px->next = 0;
+ px->prev = pf;
+ pf->next = px;
+ pf = px;
+ px = 0;
+ } else {
+ continue;
+ }
+ break;
+ }
+ }
+ if (!pf->next &&
+ pf->size > malloc_cache &&
+ pf->end == malloc_brk &&
+ malloc_brk == (void*)sbrk(0)) {
+ pf->end = pf->page + malloc_cache;
+ pf->size = malloc_cache;
+ TRACE(("%6d U %p %d\n",malloc_event++,pf->end,pf->end - pf->page));
+ brk(pf->end);
+ malloc_brk = pf->end;
+ /* Find the page directory entry for the page in question */
+ page = (u_long)pf->end >> malloc_pageshift;
+ index = page - malloc_origo;
+ /* Now update the directory */
+ for(i=index;i <= last_index;)
+ page_dir[i++] = MALLOC_NOT_MINE;
+ last_index = index - 1;
+ }
+}
+
+/*
+ * Free a chunk, and possibly the page it's on, if the page becomes empty.
+ */
+
+static void
+free_bytes(void *ptr, u_long page, int index, struct pginfo *info)
+{
+ int i;
+ struct pginfo **mp;
+ void *vp;
+
+ /* Make sure that pointer is multiplum of chunk-size */
+#ifdef SANITY
+ if ((u_long)ptr & (info->size - 1))
+ wrterror("freeing messed up chunk pointer\n");
+#endif
+
+ /* Find the chunk number on the page */
+ i = ((u_long)ptr & malloc_pagemask) >> info->shift;
+
+ /* See if it's free already */
+ if (tst_bit(info,i)) {
+#ifdef SANITY
+ wrtwarning("freeing free chunk at %p\n", ptr);
+#endif
+ return;
+ }
+
+ /* Mark it free */
+ set_bit(info,i);
+ info->free++;
+
+ /* If the page was full before, we need to put it on the queue now */
+ if (info->free == 1) {
+ mp = page_dir + info->shift;
+ while (*mp && (*mp)->next && (*mp)->next->page < info->page)
+ mp = &(*mp)->next;
+ info->next = *mp;
+ *mp = info;
+ return;
+ }
+
+ /* If this page isn't empty, don't do anything. */
+ if (info->free != info->total)
+ return;
+
+ /* We may want to keep at least one page of each size chunks around. */
+ mp = page_dir + info->shift;
+ if (0 && (*mp == info) && !info->next)
+ return;
+
+ /* Find & remove this page in the queue */
+ while (*mp != info) {
+ mp = &((*mp)->next);
+#ifdef EXTRA_SANITY
+ if (!*mp) {
+ TRACE(("%6d !q %p\n",malloc_event++,info));
+ wrterror("Not on queue\n");
+ }
+#endif
+ }
+ *mp = info->next;
+
+ /* Free the page & the info structure if need be */
+ set_pgdir(info->page,MALLOC_FIRST);
+ if((void*)info->page == (void*)info) {
+ _PR_UnlockedFree(info->page);
+ } else {
+ vp = info->page;
+ _PR_UnlockedFree(info);
+ _PR_UnlockedFree(vp);
+ }
+}
+
+void _PR_UnlockedFree(void *ptr)
+{
+ u_long page;
+ struct pginfo *info;
+ int index, tmp_index;
+
+ TRACE(("%6d F %p\n",malloc_event++,ptr));
+ /* This is legal */
+ if (!ptr)
+ return;
+
+#ifdef SANITY
+ /* There wouldn't be anything to free */
+ if (!initialized) {
+ wrtwarning("free() called before malloc() ever got called\n");
+ return;
+ }
+#endif
+
+#ifdef SANITY
+ if (suicide)
+ PR_Abort();
+#endif
+
+ /* Find the page directory entry for the page in question */
+ page = (u_long)ptr >> malloc_pageshift;
+ index = page - malloc_origo;
+
+ /*
+ * check if memory was allocated by memalign
+ */
+ tmp_index = index;
+ while (page_dir[tmp_index] == MALLOC_FOLLOW)
+ tmp_index--;
+ if (tmp_index != index) {
+ /*
+ * memalign-allocated memory
+ */
+ index = tmp_index;
+ page = index + malloc_origo;
+ ptr = (void *) (page << malloc_pageshift);
+ }
+ /* make sure it makes sense in some fashion */
+ if (index < malloc_pageshift) {
+#ifdef SANITY
+ wrtwarning("junk pointer %p (low) passed to free()\n", ptr);
+#endif
+ return;
+ }
+ if (index > last_index) {
+#ifdef SANITY
+ wrtwarning("junk pointer %p (high) passed to free()\n", ptr);
+#endif
+ return;
+ }
+
+ /* handle as page-allocation or chunk allocation */
+ info = page_dir[index];
+ if (info < MALLOC_MAGIC)
+ free_pages((char*)ptr, page, index, info);
+ else
+ free_bytes(ptr,page,index,info);
+ return;
+}
+#endif /* _PR_OVERRIDE_MALLOC */