scoutos / prex-0.9.0 / sys / lib / string.c @ 03e9c04a
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/*-
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* Copyright (c) 2005-2006, Kohsuke Ohtani
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the author nor the names of any co-contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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/*
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* string.c - Minimum string library for kernel
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*/
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#include <kernel.h> |
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/*
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* Safer version of strncpy
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* The destination string is always terminated with NULL character.
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*/
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size_t |
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strlcpy(char *dest, const char *src, size_t count) |
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{ |
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char *d = dest;
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const char *s = src; |
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size_t n = count; |
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/* Copy as many bytes as will fit */
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if (n != 0 && --n != 0) { |
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do {
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if ((*d++ = *s++) == 0) |
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break;
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} while (--n != 0); |
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} |
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/* Not enough room in dst, add NUL and traverse rest of src */
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if (n == 0) { |
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if (count != 0) |
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*d = '\0'; /* NUL-terminate dst */ |
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while (*s++)
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; |
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} |
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return (size_t)(s - src - 1); /* count does not include NUL */ |
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} |
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int
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strncmp(const char *src, const char *tgt, size_t count) |
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{ |
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signed char res = 0; |
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while (count) {
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if ((res = *src - *tgt++) != 0 || !*src++) |
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break;
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count--; |
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} |
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return res;
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} |
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/* The returned size does not include the last NULL char */
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size_t |
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strnlen(const char *str, size_t count) |
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{ |
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const char *tmp; |
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for (tmp = str; count-- && *tmp != '\0'; ++tmp); |
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return (size_t)(tmp - str);
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} |
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void *
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memcpy(void *dest, const void *src, size_t count) |
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{ |
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char *tmp = (char *)dest, *s = (char *)src; |
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ASSERT(count != 0);
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while (count--)
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*tmp++ = *s++; |
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return dest;
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} |
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void *
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memset(void *dest, int ch, size_t count) |
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{ |
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char *p = (char *)dest; |
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ASSERT(count != 0);
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while (count--)
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*p++ = (char)ch;
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return dest;
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} |