Return to string.c CVS log

Up to [local] / prex / sys / lib

Annotation of prex/sys/lib/string.c, Revision 1.1

1.1     ! nbrk        1: /*-
        !             2:  * Copyright (c) 2005-2006, Kohsuke Ohtani
        !             3:  * All rights reserved.
        !             4:  *
        !             5:  * Redistribution and use in source and binary forms, with or without
        !             6:  * modification, are permitted provided that the following conditions
        !             7:  * are met:
        !             8:  * 1. Redistributions of source code must retain the above copyright
        !             9:  *    notice, this list of conditions and the following disclaimer.
        !            10:  * 2. Redistributions in binary form must reproduce the above copyright
        !            11:  *    notice, this list of conditions and the following disclaimer in the
        !            12:  *    documentation and/or other materials provided with the distribution.
        !            13:  * 3. Neither the name of the author nor the names of any co-contributors
        !            14:  *    may be used to endorse or promote products derived from this software
        !            15:  *    without specific prior written permission.
        !            16:  *
        !            17:  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
        !            18:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
        !            19:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
        !            20:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
        !            21:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
        !            22:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
        !            23:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
        !            24:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
        !            25:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
        !            26:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
        !            27:  * SUCH DAMAGE.
        !            28:  */
        !            29:
        !            30: /*
        !            31:  * string.c - Minimum string library for kernel
        !            32:  */
        !            33:
        !            34: #include <sys/types.h>
        !            35: #include <kernel.h>
        !            36:
        !            37: /*
        !            38:  * Safer version of strncpy
        !            39:  * The destination string is always terminated with NULL character.
        !            40:  */
        !            41: size_t
        !            42: strlcpy(char *dest, const char *src, size_t count)
        !            43: {
        !            44:        char *d = dest;
        !            45:        const char *s = src;
        !            46:        size_t n = count;
        !            47:
        !            48:        /* Copy as many bytes as will fit */
        !            49:        if (n != 0 && --n != 0) {
        !            50:                do {
        !            51:                        if ((*d++ = *s++) == 0)
        !            52:                                break;
        !            53:                } while (--n != 0);
        !            54:        }
        !            55:
        !            56:        /* Not enough room in dst, add NUL and traverse rest of src */
        !            57:        if (n == 0) {
        !            58:                if (count != 0)
        !            59:                        *d = '\0';              /* NUL-terminate dst */
        !            60:                while (*s++)
        !            61:                        ;
        !            62:        }
        !            63:
        !            64:        return (size_t)(s - src - 1);   /* count does not include NUL */
        !            65: }
        !            66:
        !            67: int
        !            68: strncmp(const char *src, const char *tgt, size_t count)
        !            69: {
        !            70:        signed char res = 0;
        !            71:
        !            72:        while (count) {
        !            73:                if ((res = *src - *tgt++) != 0 || !*src++)
        !            74:                        break;
        !            75:                count--;
        !            76:        }
        !            77:        return res;
        !            78: }
        !            79:
        !            80: /* The returned size does not include the last NULL char */
        !            81: size_t
        !            82: strnlen(const char *str, size_t count)
        !            83: {
        !            84:        const char *tmp;
        !            85:
        !            86:        for (tmp = str; count-- && *tmp != '\0'; ++tmp);
        !            87:        return (size_t)(tmp - str);
        !            88: }
        !            89:
        !            90: void *
        !            91: memcpy(void *dest, const void *src, size_t count)
        !            92: {
        !            93:        char *tmp = (char *)dest, *s = (char *)src;
        !            94:
        !            95:        while (count--)
        !            96:                *tmp++ = *s++;
        !            97:
        !            98:        return dest;
        !            99: }
        !           100:
        !           101: void *
        !           102: memset(void *dest, int ch, size_t count)
        !           103: {
        !           104:        char *p = (char *)dest;
        !           105:
        !           106:        while (count--)
        !           107:                *p++ = (char)ch;
        !           108:
        !           109:        return dest;
        !           110: }