| /* |
| * This string-include defines all string functions as inline |
| * functions. Use gcc. It also assumes ds=es=data space, this should be |
| * normal. Most of the string-functions are rather heavily hand-optimized, |
| * see especially strtok,strstr,str[c]spn. They should work, but are not |
| * very easy to understand. Everything is done entirely within the register |
| * set, making the functions fast and clean. String instructions have been |
| * used through-out, making for "slightly" unclear code :-) |
| * |
| * NO Copyright (C) 1991, 1992 Linus Torvalds, |
| * consider these trivial functions to be PD. |
| */ |
| |
| /* |
| * Copyright (C) 2000-2005 Erik Andersen <andersen@uclibc.org> |
| * |
| * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball. |
| */ |
| |
| /* |
| * Modified for uClibc by Erik Andersen <andersen@codepoet.org> |
| * These make no attempt to use nifty things like mmx/3dnow/etc. |
| * These are not inline, and will therefore not be as fast as |
| * modifying the headers to use inlines (and cannot therefore |
| * do tricky things when dealing with const memory). But they |
| * should (I hope!) be faster than their generic equivalents.... |
| * |
| * More importantly, these should provide a good example for |
| * others to follow when adding arch specific optimizations. |
| * -Erik |
| */ |
| |
| #include <string.h> |
| |
| #ifdef __USE_GNU |
| |
| #undef strnlen |
| /*#define strnlen TESTING*/ |
| size_t strnlen(const char *s, size_t count) |
| { |
| int edx; |
| int eax; |
| __asm__ __volatile__( |
| " leal -1(%%ecx), %%eax\n" |
| "1: incl %%eax\n" |
| " decl %%edx\n" |
| " jz 3f\n" |
| " cmpb $0, (%%eax)\n" |
| " jnz 1b\n" |
| "3: subl %%ecx, %%eax" |
| : "=a" (eax), "=&d" (edx) |
| : "c" (s), "1" (count + 1) |
| ); |
| return eax; |
| } |
| #ifndef strnlen |
| libc_hidden_def(strnlen) |
| #else |
| /* Uncomment TESTING, gcc -D_GNU_SOURCE -m32 -Os strnlen.c -o strnlen |
| * and run ./strnlen |
| */ |
| int main() |
| { |
| printf(strnlen("abc\0def", -2) == 3 ? "ok\n" : "BAD!\n"); |
| printf(strnlen("abc\0def", -1) == 3 ? "ok\n" : "BAD!\n"); |
| printf(strnlen("abc\0def", 0) == 0 ? "ok\n" : "BAD!\n"); |
| printf(strnlen("abc\0def", 1) == 1 ? "ok\n" : "BAD!\n"); |
| printf(strnlen("abc\0def", 2) == 2 ? "ok\n" : "BAD!\n"); |
| printf(strnlen("abc\0def", 3) == 3 ? "ok\n" : "BAD!\n"); |
| printf(strnlen("abc\0def", 4) == 3 ? "ok\n" : "BAD!\n"); |
| printf(strnlen("abc\0def", 5) == 3 ? "ok\n" : "BAD!\n"); |
| } |
| #endif |
| |
| #endif |