X-Git-Url: https://git.saurik.com/apple/security.git/blobdiff_plain/5dd5f9ec28f304ca377c42fd7f711d6cf12b90e1..5c19dc3ae3bd8e40a9c028b0deddd50ff337692c:/OSX/libsecurity_asn1/lib/plarena.c diff --git a/OSX/libsecurity_asn1/lib/plarena.c b/OSX/libsecurity_asn1/lib/plarena.c new file mode 100644 index 00000000..d7073980 --- /dev/null +++ b/OSX/libsecurity_asn1/lib/plarena.c @@ -0,0 +1,423 @@ +/* + * Copyright (c) 2003-2006,2008,2010-2012 Apple Inc. All Rights Reserved. + * + * @APPLE_LICENSE_HEADER_START@ + * + * This file contains Original Code and/or Modifications of Original Code + * as defined in and that are subject to the Apple Public Source License + * Version 2.0 (the 'License'). You may not use this file except in + * compliance with the License. Please obtain a copy of the License at + * http://www.opensource.apple.com/apsl/ and read it before using this + * file. + * + * The Original Code and all software distributed under the License are + * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER + * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, + * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. + * Please see the License for the specific language governing rights and + * limitations under the License. + * + * @APPLE_LICENSE_HEADER_END@ + */ +/* + * The contents of this file are subject to the Mozilla Public + * License Version 1.1 (the "License"); you may not use this file + * except in compliance with the License. You may obtain a copy of + * the License at http://www.mozilla.org/MPL/ + * + * Software distributed under the License is distributed on an "AS + * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or + * implied. See the License for the specific language governing + * rights and limitations under the License. + * + * The Original Code is the Netscape Portable Runtime (NSPR). + * + * The Initial Developer of the Original Code is Netscape + * Communications Corporation. Portions created by Netscape are + * Copyright (C) 1998-2000 Netscape Communications Corporation. All + * Rights Reserved. + * + * Contributor(s): + * + * Alternatively, the contents of this file may be used under the + * terms of the GNU General Public License Version 2 or later (the + * "GPL"), in which case the provisions of the GPL are applicable + * instead of those above. If you wish to allow use of your + * version of this file only under the terms of the GPL and not to + * allow others to use your version of this file under the MPL, + * indicate your decision by deleting the provisions above and + * replace them with the notice and other provisions required by + * the GPL. If you do not delete the provisions above, a recipient + * may use your version of this file under either the MPL or the + * GPL. + */ + +/* + * Lifetime-based fast allocation, inspired by much prior art, including + * "Fast Allocation and Deallocation of Memory Based on Object Lifetimes" + * David R. Hanson, Software -- Practice and Experience, Vol. 20(1). + */ +#include +#include +#include "plarena.h" +#include "prmem.h" +#include "prbit.h" +#include "prlog.h" +#include "prinit.h" + +#ifdef PL_ARENAMETER +static PLArenaStats *arena_stats_list; + +#define COUNT(pool,what) (pool)->stats.what++ +#else +#define COUNT(pool,what) /* nothing */ +#endif + +#define PL_ARENA_DEFAULT_ALIGN sizeof(double) + +PR_IMPLEMENT(void) PL_InitArenaPool( + PLArenaPool *pool, const char *name, PRUint32 size, PRUint32 align) +{ +#if !defined (__GNUC__) +#pragma unused (name) +#endif + + if (align == 0) + align = PL_ARENA_DEFAULT_ALIGN; + pool->mask = PR_BITMASK(PR_CeilingLog2(align)); + pool->first.next = NULL; + pool->first.base = pool->first.avail = pool->first.limit = + (PRUword)PL_ARENA_ALIGN(pool, &pool->first + 1); + pool->current = &pool->first; + pool->arenasize = size; +#ifdef PL_ARENAMETER + memset(&pool->stats, 0, sizeof pool->stats); + pool->stats.name = strdup(name); + pool->stats.next = arena_stats_list; + arena_stats_list = &pool->stats; +#endif +} + +#if __APPLE__ +#define MAX_SIZE (PR_UINT32_MAX >> 1) +#endif + +/* +** PL_ArenaAllocate() -- allocate space from an arena pool +** +** Description: PL_ArenaAllocate() allocates space from an arena +** pool. +** +** First, try to satisfy the request from arenas starting at +** pool->current. Then try to allocate a new arena from the heap. +** +** Returns: pointer to allocated space or NULL +** +** Notes: The original implementation had some difficult to +** solve bugs; the code was difficult to read. Sometimes it's +** just easier to rewrite it. I did that. larryh. +** +** See also: bugzilla: 45343. +** +*/ + +PR_IMPLEMENT(void *) PL_ArenaAllocate(PLArenaPool *pool, PRUint32 nb) +{ + PLArena *a; + char *rp; /* returned pointer */ + + PR_ASSERT((nb & pool->mask) == 0); +#ifdef __APPLE__ + nb = PL_ARENA_ALIGN(pool, nb); /* force alignment, cast is useless/causes warning. */ +#else + nb = (PRUword)PL_ARENA_ALIGN(pool, nb); /* force alignment */ +#endif + + /* attempt to allocate from arenas at pool->current */ + { + a = pool->current; + do { + if ( nb <= a->limit - a->avail ) { + pool->current = a; + rp = (char *)a->avail; + a->avail += nb; + return rp; + } + } while( NULL != (a = a->next) ); + } + + /* attempt to allocate from the heap */ + { + PRUint32 sz = PR_MAX(pool->arenasize, nb); + if (PR_UINT32_MAX - sz < sizeof *a + pool->mask) { + a = NULL; + } else { + sz += sizeof *a + pool->mask; /* header and alignment slop */ + a = (PLArena*)PR_MALLOC(sz); + } +#ifdef __APPLE__ + // Check for integer overflow on a->avail += nb + PRUword a_avail_tmp=(PRUword)PL_ARENA_ALIGN(pool, a + 1); + if (a_avail_tmp + nb < a_avail_tmp) + { + PR_FREEIF(a); // Set a back to NULL + } +#endif + if ( NULL != a ) { + a->limit = (PRUword)a + sz; +#ifdef __APPLE__ + a->base = a->avail = a_avail_tmp; +#else + a->base = a->avail = (PRUword)PL_ARENA_ALIGN(pool, a + 1); +#endif + rp = (char *)a->avail; + a->avail += nb; + /* the newly allocated arena is linked after pool->current + * and becomes pool->current */ + a->next = pool->current->next; + pool->current->next = a; + pool->current = a; + if ( NULL == pool->first.next ) + pool->first.next = a; + PL_COUNT_ARENA(pool,++); + COUNT(pool, nmallocs); + return(rp); + } + } + + /* we got to here, and there's no memory to allocate */ + return(NULL); +} /* --- end PL_ArenaAllocate() --- */ + +/* + * Grow, a.k.a. realloc. The PL_ARENA_GROW macro has already handled + * the possible grow-in-place action in which the current PLArena is the + * source of the incoming pointer, and there is room in that arena for + * the requested size. + */ +PR_IMPLEMENT(void *) PL_ArenaGrow( + PLArenaPool *pool, void *p, PRUint32 origSize, PRUint32 incr) +{ + void *newp; + PLArena *thisArena; + PLArena *lastArena; + PRUint32 origAlignSize; // bytes currently reserved for caller + PRUint32 newSize; // bytes actually mallocd here + + /* expand at least by 2x */ + origAlignSize = PL_ARENA_ALIGN(pool, origSize); + newSize = PR_MAX(origAlignSize+incr, 2*origAlignSize); + newSize = PL_ARENA_ALIGN(pool, newSize); +#if __APPLE__ + // Enforce maximal size before any potential implicit truncation + if (newSize>=MAX_SIZE || origSize>=MAX_SIZE || incr>=MAX_SIZE) { + return NULL; + } +#endif + PL_ARENA_ALLOCATE(newp, pool, newSize); + if (newp == NULL) { + return NULL; + } + /* + * Trim back the memory we just allocated to the amount our caller really + * needs, leaving the remainder for grow-in-place on subsequent calls + * to PL_ARENA_GROW. + */ + PRUint32 newAlignSize = PL_ARENA_ALIGN(pool, origSize+incr); + PR_ASSERT(pool->current->avail == ((PRUword)newp + newSize)); + pool->current->avail = (PRUword)newp + newAlignSize; + PR_ASSERT(pool->current->avail <= pool->current->limit); + + /* "realloc" */ + memcpy(newp, p, origSize); + + /* + * Free old memory only if it's the entire outstanding allocated + * memory associated with one of our known PLArenas. + */ + lastArena = &pool->first; /* pool->first always empty */ + thisArena = lastArena->next; /* so, start here */ + + PRUword origPtr = (PRUword)p; + while(thisArena != NULL) { + if(origPtr == thisArena->base) { + if((origPtr + origAlignSize) == thisArena->avail) { + /* unlink */ + lastArena->next = thisArena->next; + + /* and free */ + PL_CLEAR_ARENA(thisArena); + PL_COUNT_ARENA(pool,--); + PR_DELETE(thisArena); + break; + } + } + lastArena = thisArena; + thisArena = thisArena->next; + } + /* + * Note: inability to free is not an error; it just causes a temporary leak + * of the old buffer (until the arena pool is freed, of course). + */ + return newp; +} + +static void ClearArenaList(PLArena *a, PRInt32 pattern) +{ + + for (; a; a = a->next) { + PR_ASSERT(a->base <= a->avail && a->avail <= a->limit); + a->avail = a->base; + PL_CLEAR_UNUSED_PATTERN(a, pattern); + } +} + +PR_IMPLEMENT(void) PL_ClearArenaPool(PLArenaPool *pool, PRInt32 pattern) +{ + ClearArenaList(pool->first.next, pattern); +} + +/* + * Free tail arenas linked after head, which may not be the true list head. + * Reset pool->current to point to head in case it pointed at a tail arena. + */ +static void FreeArenaList(PLArenaPool *pool, PLArena *head, PRBool reallyFree) +{ + PLArena **ap, *a; + + ap = &head->next; + a = *ap; + if (!a) + return; + + do { + *ap = a->next; + PL_CLEAR_ARENA(a); + PL_COUNT_ARENA(pool,--); + PR_DELETE(a); + } while ((a = *ap) != 0); + + pool->current = head; +} + +PR_IMPLEMENT(void) PL_ArenaRelease(PLArenaPool *pool, char *mark) +{ + #if ARENA_MARK_ENABLE + PLArena *a; + + for (a = pool->first.next; a; a = a->next) { + if (PR_UPTRDIFF(mark, a->base) < PR_UPTRDIFF(a->avail, a->base)) { + a->avail = (PRUword)PL_ARENA_ALIGN(pool, mark); + FreeArenaList(pool, a, PR_FALSE); + return; + } + } + #endif /* ARENA_MARK_ENABLE */ +} + +PR_IMPLEMENT(void) PL_FreeArenaPool(PLArenaPool *pool) +{ + FreeArenaList(pool, &pool->first, PR_FALSE); + COUNT(pool, ndeallocs); +} + +PR_IMPLEMENT(void) PL_FinishArenaPool(PLArenaPool *pool) +{ + FreeArenaList(pool, &pool->first, PR_TRUE); +#ifdef PL_ARENAMETER + { + PLArenaStats *stats, **statsp; + + if (pool->stats.name) + PR_DELETE(pool->stats.name); + for (statsp = &arena_stats_list; (stats = *statsp) != 0; + statsp = &stats->next) { + if (stats == &pool->stats) { + *statsp = stats->next; + return; + } + } + } +#endif +} + +PR_IMPLEMENT(void) PL_CompactArenaPool(PLArenaPool *ap) +{ +} + +PR_IMPLEMENT(void) PL_ArenaFinish(void) +{ +} + +#ifdef PL_ARENAMETER +PR_IMPLEMENT(void) PL_ArenaCountAllocation(PLArenaPool *pool, PRUint32 nb) +{ + pool->stats.nallocs++; + pool->stats.nbytes += nb; + if (nb > pool->stats.maxalloc) + pool->stats.maxalloc = nb; + pool->stats.variance += nb * nb; +} + +PR_IMPLEMENT(void) PL_ArenaCountInplaceGrowth( + PLArenaPool *pool, PRUint32 size, PRUint32 incr) +{ + pool->stats.ninplace++; +} + +PR_IMPLEMENT(void) PL_ArenaCountGrowth( + PLArenaPool *pool, PRUint32 size, PRUint32 incr) +{ + pool->stats.ngrows++; + pool->stats.nbytes += incr; + pool->stats.variance -= size * size; + size += incr; + if (size > pool->stats.maxalloc) + pool->stats.maxalloc = size; + pool->stats.variance += size * size; +} + +PR_IMPLEMENT(void) PL_ArenaCountRelease(PLArenaPool *pool, char *mark) +{ + pool->stats.nreleases++; +} + +PR_IMPLEMENT(void) PL_ArenaCountRetract(PLArenaPool *pool, char *mark) +{ + pool->stats.nfastrels++; +} + +#include +#include + +PR_IMPLEMENT(void) PL_DumpArenaStats(FILE *fp) +{ + PLArenaStats *stats; + double mean, variance; + + for (stats = arena_stats_list; stats; stats = stats->next) { + if (stats->nallocs != 0) { + mean = (double)stats->nbytes / stats->nallocs; + variance = fabs(stats->variance / stats->nallocs - mean * mean); + } else { + mean = variance = 0; + } + + fprintf(fp, "\n%s allocation statistics:\n", stats->name); + fprintf(fp, " number of arenas: %u\n", stats->narenas); + fprintf(fp, " number of allocations: %u\n", stats->nallocs); + fprintf(fp, " number of free arena reclaims: %u\n", stats->nreclaims); + fprintf(fp, " number of malloc calls: %u\n", stats->nmallocs); + fprintf(fp, " number of deallocations: %u\n", stats->ndeallocs); + fprintf(fp, " number of allocation growths: %u\n", stats->ngrows); + fprintf(fp, " number of in-place growths: %u\n", stats->ninplace); + fprintf(fp, "number of released allocations: %u\n", stats->nreleases); + fprintf(fp, " number of fast releases: %u\n", stats->nfastrels); + fprintf(fp, " total bytes allocated: %u\n", stats->nbytes); + fprintf(fp, " mean allocation size: %g\n", mean); + fprintf(fp, " standard deviation: %g\n", sqrt(variance)); + fprintf(fp, " maximum allocation size: %u\n", stats->maxalloc); + } +} +#endif /* PL_ARENAMETER */