memalign.c (1743B)
1 /* 2 * Copyright (c) 2003 Gunnar Ritter 3 * 4 * This software is provided 'as-is', without any express or implied 5 * warranty. In no event will the authors be held liable for any damages 6 * arising from the use of this software. 7 * 8 * Permission is granted to anyone to use this software for any purpose, 9 * including commercial applications, and to alter it and redistribute 10 * it freely, subject to the following restrictions: 11 * 12 * 1. The origin of this software must not be misrepresented; you must not 13 * claim that you wrote the original software. If you use this software 14 * in a product, an acknowledgment in the product documentation would be 15 * appreciated but is not required. 16 * 17 * 2. Altered source versions must be plainly marked as such, and must not be 18 * misrepresented as being the original software. 19 * 20 * 3. This notice may not be removed or altered from any source distribution. 21 */ 22 /* Sccsid @(#)memalign.c 1.7 (gritter) 1/22/06 */ 23 24 #if defined (__FreeBSD__) || defined (__dietlibc__) || defined (_AIX) || \ 25 defined (__NetBSD__) || defined (__OpenBSD__) || \ 26 defined (__DragonFly__) || defined (__APPLE__) 27 /* 28 * FreeBSD malloc(3) promises to page-align the return of malloc() calls 29 * if size is at least a page. This serves for a poor man's memalign() 30 * implementation that matches our needs. 31 */ 32 #include <unistd.h> 33 #include <stdlib.h> 34 35 #include "memalign.h" 36 37 void * 38 memalign(size_t alignment, size_t size) 39 { 40 static long pagesize; 41 42 if (pagesize == 0) 43 pagesize = sysconf(_SC_PAGESIZE); 44 if (alignment != pagesize) 45 return NULL; 46 if (size < pagesize) 47 size = pagesize; 48 return malloc(size); 49 } 50 #endif /* __FreeBSD__ || __dietlibc__ || _AIX || __NetBSD__ || __OpenBSD__ || 51 __DragonFly__ || __APPLE__ */