/* * * It has originally been taken from the HelenOS project * (http://www.helenos.eu), and slightly modified for our purposes. * * Copyright (c) 2005 Martin Decky * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * - The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include <libpayload.h> static void *default_memset(void *const s, const int c, size_t n) { size_t i; u8 *dst = s; unsigned long w = c & 0xff; const u8 *const aligned_start = (const u8 *)ALIGN_UP((uintptr_t)dst, sizeof(unsigned long)); for (; n > 0 && dst != aligned_start; --n, ++dst) *dst = (u8)c; for (i = 1; i < sizeof(unsigned long); i <<= 1) w = (w << (i * 8)) | w; for (i = 0; i < n / sizeof(unsigned long); i++) ((unsigned long *)dst)[i] = w; dst += i * sizeof(unsigned long); for (i = 0; i < n % sizeof(unsigned long); i++) dst[i] = (u8)c; return s; } void *memset(void *s, int c, size_t n) __attribute__((weak, alias("default_memset"))); static void *default_memcpy(void *dst, const void *src, size_t n) { size_t i; void *ret = dst; if (IS_ALIGNED((uintptr_t)dst, sizeof(unsigned long)) && IS_ALIGNED((uintptr_t)src, sizeof(unsigned long))) { for (i = 0; i < n / sizeof(unsigned long); i++) ((unsigned long *)dst)[i] = ((unsigned long *)src)[i]; src += i * sizeof(unsigned long); dst += i * sizeof(unsigned long); n -= i * sizeof(unsigned long); } for (i = 0; i < n; i++) ((u8 *)dst)[i] = ((u8 *)src)[i]; return ret; } void *memcpy(void *dst, const void *src, size_t n) __attribute__((weak, alias("default_memcpy"))); static void *default_memmove(void *dst, const void *src, size_t n) { size_t offs; ssize_t i; if (src > dst) return default_memcpy(dst, src, n); if (!IS_ALIGNED((uintptr_t)dst, sizeof(unsigned long)) || !IS_ALIGNED((uintptr_t)src, sizeof(unsigned long))) { for (i = n - 1; i >= 0; i--) ((u8 *)dst)[i] = ((u8 *)src)[i]; return dst; } offs = n - (n % sizeof(unsigned long)); for (i = (n % sizeof(unsigned long)) - 1; i >= 0; i--) ((u8 *)dst)[i + offs] = ((u8 *)src)[i + offs]; for (i = n / sizeof(unsigned long) - 1; i >= 0; i--) ((unsigned long *)dst)[i] = ((unsigned long *)src)[i]; return dst; } void *memmove(void *dst, const void *src, size_t n) __attribute__((weak, alias("default_memmove"))); /** * Compare two memory areas. * * @param s1 Pointer to the first area to compare. * @param s2 Pointer to the second area to compare. * @param n Size of the first area in bytes (both must have the same length). * @return If n is 0, return zero. Otherwise, return a value less than, equal * to, or greater than zero if s1 is found less than, equal to, or * greater than s2 respectively. */ static int default_memcmp(const void *s1, const void *s2, size_t n) { size_t i = 0; const unsigned long *w1 = s1, *w2 = s2; if (IS_ALIGNED((uintptr_t)s1, sizeof(unsigned long)) && IS_ALIGNED((uintptr_t)s2, sizeof(unsigned long))) for (; i < n / sizeof(unsigned long); i++) if (w1[i] != w2[i]) break; /* fall through to find differing byte */ for (i *= sizeof(unsigned long); i < n; i++) if (((u8 *)s1)[i] != ((u8 *)s2)[i]) return ((u8 *)s1)[i] - ((u8 *)s2)[i]; return 0; } int memcmp(const void *s1, const void *s2, size_t n) __attribute__((weak, alias("default_memcmp"))); void *memchr(const void *s, int c, size_t n) { unsigned char *p = (unsigned char *)s; while (n--) if (*p != (unsigned char)c) p++; else return p; return 0; }