Chris@1: /* alloc - Convenience routines for safely allocating memory
Chris@1:  * Copyright (C) 2007  Josh Coalson
Chris@1:  *
Chris@1:  * This library is free software; you can redistribute it and/or
Chris@1:  * modify it under the terms of the GNU Lesser General Public
Chris@1:  * License as published by the Free Software Foundation; either
Chris@1:  * version 2.1 of the License, or (at your option) any later version.
Chris@1:  *
Chris@1:  * This library is distributed in the hope that it will be useful,
Chris@1:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
Chris@1:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Chris@1:  * Lesser General Public License for more details.
Chris@1:  *
Chris@1:  * You should have received a copy of the GNU Lesser General Public
Chris@1:  * License along with this library; if not, write to the Free Software
Chris@1:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
Chris@1:  */
Chris@1: 
Chris@1: #ifndef FLAC__SHARE__ALLOC_H
Chris@1: #define FLAC__SHARE__ALLOC_H
Chris@1: 
Chris@1: #if HAVE_CONFIG_H
Chris@1: #  include <config.h>
Chris@1: #endif
Chris@1: 
Chris@1: /* WATCHOUT: for c++ you may have to #define __STDC_LIMIT_MACROS 1 real early
Chris@1:  * before #including this file,  otherwise SIZE_MAX might not be defined
Chris@1:  */
Chris@1: 
Chris@1: #include <limits.h> /* for SIZE_MAX */
Chris@4: #if !defined _MSC_VER && !defined __EMX__
Chris@1: #include <stdint.h> /* for SIZE_MAX in case limits.h didn't get it */
Chris@1: #endif
Chris@1: #include <stdlib.h> /* for size_t, malloc(), etc */
Chris@1: 
Chris@1: #ifndef SIZE_MAX
Chris@1: # ifndef SIZE_T_MAX
Chris@1: #  ifdef _MSC_VER
Chris@1: #   define SIZE_T_MAX UINT_MAX
Chris@1: #  else
Chris@1: #   error
Chris@1: #  endif
Chris@1: # endif
Chris@1: # define SIZE_MAX SIZE_T_MAX
Chris@1: #endif
Chris@1: 
Chris@1: #ifndef FLaC__INLINE
Chris@1: #define FLaC__INLINE
Chris@1: #endif
Chris@1: 
Chris@1: /* avoid malloc()ing 0 bytes, see:
Chris@1:  * https://www.securecoding.cert.org/confluence/display/seccode/MEM04-A.+Do+not+make+assumptions+about+the+result+of+allocating+0+bytes?focusedCommentId=5407003
Chris@1: */
Chris@1: static FLaC__INLINE void *safe_malloc_(size_t size)
Chris@1: {
Chris@1: 	/* malloc(0) is undefined; FLAC src convention is to always allocate */
Chris@1: 	if(!size)
Chris@1: 		size++;
Chris@1: 	return malloc(size);
Chris@1: }
Chris@1: 
Chris@1: static FLaC__INLINE void *safe_calloc_(size_t nmemb, size_t size)
Chris@1: {
Chris@1: 	if(!nmemb || !size)
Chris@1: 		return malloc(1); /* malloc(0) is undefined; FLAC src convention is to always allocate */
Chris@1: 	return calloc(nmemb, size);
Chris@1: }
Chris@1: 
Chris@1: /*@@@@ there's probably a better way to prevent overflows when allocating untrusted sums but this works for now */
Chris@1: 
Chris@1: static FLaC__INLINE void *safe_malloc_add_2op_(size_t size1, size_t size2)
Chris@1: {
Chris@1: 	size2 += size1;
Chris@1: 	if(size2 < size1)
Chris@1: 		return 0;
Chris@1: 	return safe_malloc_(size2);
Chris@1: }
Chris@1: 
Chris@1: static FLaC__INLINE void *safe_malloc_add_3op_(size_t size1, size_t size2, size_t size3)
Chris@1: {
Chris@1: 	size2 += size1;
Chris@1: 	if(size2 < size1)
Chris@1: 		return 0;
Chris@1: 	size3 += size2;
Chris@1: 	if(size3 < size2)
Chris@1: 		return 0;
Chris@1: 	return safe_malloc_(size3);
Chris@1: }
Chris@1: 
Chris@1: static FLaC__INLINE void *safe_malloc_add_4op_(size_t size1, size_t size2, size_t size3, size_t size4)
Chris@1: {
Chris@1: 	size2 += size1;
Chris@1: 	if(size2 < size1)
Chris@1: 		return 0;
Chris@1: 	size3 += size2;
Chris@1: 	if(size3 < size2)
Chris@1: 		return 0;
Chris@1: 	size4 += size3;
Chris@1: 	if(size4 < size3)
Chris@1: 		return 0;
Chris@1: 	return safe_malloc_(size4);
Chris@1: }
Chris@1: 
Chris@1: static FLaC__INLINE void *safe_malloc_mul_2op_(size_t size1, size_t size2)
Chris@1: #if 0
Chris@1: needs support for cases where sizeof(size_t) != 4
Chris@1: {
Chris@1: 	/* could be faster #ifdef'ing off SIZEOF_SIZE_T */
Chris@1: 	if(sizeof(size_t) == 4) {
Chris@1: 		if ((double)size1 * (double)size2 < 4294967296.0)
Chris@1: 			return malloc(size1*size2);
Chris@1: 	}
Chris@1: 	return 0;
Chris@1: }
Chris@1: #else
Chris@1: /* better? */
Chris@1: {
Chris@1: 	if(!size1 || !size2)
Chris@1: 		return malloc(1); /* malloc(0) is undefined; FLAC src convention is to always allocate */
Chris@1: 	if(size1 > SIZE_MAX / size2)
Chris@1: 		return 0;
Chris@1: 	return malloc(size1*size2);
Chris@1: }
Chris@1: #endif
Chris@1: 
Chris@1: static FLaC__INLINE void *safe_malloc_mul_3op_(size_t size1, size_t size2, size_t size3)
Chris@1: {
Chris@1: 	if(!size1 || !size2 || !size3)
Chris@1: 		return malloc(1); /* malloc(0) is undefined; FLAC src convention is to always allocate */
Chris@1: 	if(size1 > SIZE_MAX / size2)
Chris@1: 		return 0;
Chris@1: 	size1 *= size2;
Chris@1: 	if(size1 > SIZE_MAX / size3)
Chris@1: 		return 0;
Chris@1: 	return malloc(size1*size3);
Chris@1: }
Chris@1: 
Chris@1: /* size1*size2 + size3 */
Chris@1: static FLaC__INLINE void *safe_malloc_mul2add_(size_t size1, size_t size2, size_t size3)
Chris@1: {
Chris@1: 	if(!size1 || !size2)
Chris@1: 		return safe_malloc_(size3);
Chris@1: 	if(size1 > SIZE_MAX / size2)
Chris@1: 		return 0;
Chris@1: 	return safe_malloc_add_2op_(size1*size2, size3);
Chris@1: }
Chris@1: 
Chris@1: /* size1 * (size2 + size3) */
Chris@1: static FLaC__INLINE void *safe_malloc_muladd2_(size_t size1, size_t size2, size_t size3)
Chris@1: {
Chris@1: 	if(!size1 || (!size2 && !size3))
Chris@1: 		return malloc(1); /* malloc(0) is undefined; FLAC src convention is to always allocate */
Chris@1: 	size2 += size3;
Chris@1: 	if(size2 < size3)
Chris@1: 		return 0;
Chris@1: 	return safe_malloc_mul_2op_(size1, size2);
Chris@1: }
Chris@1: 
Chris@1: static FLaC__INLINE void *safe_realloc_add_2op_(void *ptr, size_t size1, size_t size2)
Chris@1: {
Chris@1: 	size2 += size1;
Chris@1: 	if(size2 < size1)
Chris@1: 		return 0;
Chris@1: 	return realloc(ptr, size2);
Chris@1: }
Chris@1: 
Chris@1: static FLaC__INLINE void *safe_realloc_add_3op_(void *ptr, size_t size1, size_t size2, size_t size3)
Chris@1: {
Chris@1: 	size2 += size1;
Chris@1: 	if(size2 < size1)
Chris@1: 		return 0;
Chris@1: 	size3 += size2;
Chris@1: 	if(size3 < size2)
Chris@1: 		return 0;
Chris@1: 	return realloc(ptr, size3);
Chris@1: }
Chris@1: 
Chris@1: static FLaC__INLINE void *safe_realloc_add_4op_(void *ptr, size_t size1, size_t size2, size_t size3, size_t size4)
Chris@1: {
Chris@1: 	size2 += size1;
Chris@1: 	if(size2 < size1)
Chris@1: 		return 0;
Chris@1: 	size3 += size2;
Chris@1: 	if(size3 < size2)
Chris@1: 		return 0;
Chris@1: 	size4 += size3;
Chris@1: 	if(size4 < size3)
Chris@1: 		return 0;
Chris@1: 	return realloc(ptr, size4);
Chris@1: }
Chris@1: 
Chris@1: static FLaC__INLINE void *safe_realloc_mul_2op_(void *ptr, size_t size1, size_t size2)
Chris@1: {
Chris@1: 	if(!size1 || !size2)
Chris@1: 		return realloc(ptr, 0); /* preserve POSIX realloc(ptr, 0) semantics */
Chris@1: 	if(size1 > SIZE_MAX / size2)
Chris@1: 		return 0;
Chris@1: 	return realloc(ptr, size1*size2);
Chris@1: }
Chris@1: 
Chris@1: /* size1 * (size2 + size3) */
Chris@1: static FLaC__INLINE void *safe_realloc_muladd2_(void *ptr, size_t size1, size_t size2, size_t size3)
Chris@1: {
Chris@1: 	if(!size1 || (!size2 && !size3))
Chris@1: 		return realloc(ptr, 0); /* preserve POSIX realloc(ptr, 0) semantics */
Chris@1: 	size2 += size3;
Chris@1: 	if(size2 < size3)
Chris@1: 		return 0;
Chris@1: 	return safe_realloc_mul_2op_(ptr, size1, size2);
Chris@1: }
Chris@1: 
Chris@1: #endif