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/* -*- 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
#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 */