| /* |
| * |
| * 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 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; |
| } |