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Memory leaks fixed.
/***************************************************************************** * * XVID MPEG-4 VIDEO CODEC * - Aligned Memory Allocator - * * Copyright(C) 2002-2003 Edouard Gomez <ed.gomez@free.fr> * * This program is free software ; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation ; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY ; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program ; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * $Id: mem_align.c,v 1.15.2.3 2003/09/29 00:30:31 edgomez Exp $ * ****************************************************************************/ #include <stdlib.h> #include <stdio.h> #include "mem_align.h" /***************************************************************************** * xvid_malloc * * This function allocates 'size' bytes (usable by the user) on the heap and * takes care of the requested 'alignment'. * In order to align the allocated memory block, the xvid_malloc allocates * 'size' bytes + 'alignment' bytes. So try to keep alignment very small * when allocating small pieces of memory. * * NB : a block allocated by xvid_malloc _must_ be freed with xvid_free * (the libc free will return an error) * * Returned value : - NULL on error * - Pointer to the allocated aligned block * ****************************************************************************/ void * xvid_malloc(size_t size, uint8_t alignment) { uint8_t *mem_ptr; if (!alignment) { /* We have not to satisfy any alignment */ if ((mem_ptr = (uint8_t *) malloc(size + 1)) != NULL) { /* Store (mem_ptr - "real allocated memory") in *(mem_ptr-1) */ *mem_ptr = (uint8_t)1; /* Return the mem_ptr pointer */ return ((void *)(mem_ptr+1)); } } else { uint8_t *tmp; /* Allocate the required size memory + alignment so we * can realign the data if necessary */ if ((tmp = (uint8_t *) malloc(size + alignment)) != NULL) { /* Align the tmp pointer */ mem_ptr = (uint8_t *) ((ptr_t) (tmp + alignment - 1) & (~(ptr_t) (alignment - 1))); /* Special case where malloc have already satisfied the alignment * We must add alignment to mem_ptr because we must store * (mem_ptr - tmp) in *(mem_ptr-1) * If we do not add alignment to mem_ptr then *(mem_ptr-1) points * to a forbidden memory space */ if (mem_ptr == tmp) mem_ptr += alignment; /* (mem_ptr - tmp) is stored in *(mem_ptr-1) so we are able to retrieve * the real malloc block allocated and free it in xvid_free */ *(mem_ptr - 1) = (uint8_t) (mem_ptr - tmp); /* Return the aligned pointer */ return ((void *)mem_ptr); } } return(NULL); } /***************************************************************************** * xvid_free * * Free a previously 'xvid_malloc' allocated block. Does not free NULL * references. * * Returned value : None. * ****************************************************************************/ void xvid_free(void *mem_ptr) { uint8_t *ptr; if (mem_ptr == NULL) return; /* Aligned pointer */ ptr = mem_ptr; /* *(ptr - 1) holds the offset to the real allocated block * we sub that offset os we free the real pointer */ ptr -= *(ptr - 1); /* Free the memory */ free(ptr); }
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