NetBSD/lib/libc/locale/aliasname.c

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/* $NetBSD: aliasname.c,v 1.1 2002/02/13 07:45:52 yamt Exp $ */
/*-
* Copyright (c)2002 YAMAMOTO Takashi,
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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 <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: aliasname.c,v 1.1 2002/02/13 07:45:52 yamt Exp $");
#endif /* LIBC_SCCS and not lint */
#include <assert.h>
#include <stdio.h>
#include <string.h>
#include "aliasname_local.h"
__inline int __is_ws(char);
__inline int __is_ws(char ch)
{
return (ch == ' ' || ch == '\t');
}
const char *
__unaliasname(const char *dbname, const char *alias, void *buf, size_t bufsize)
{
FILE *fp = NULL;
const char *result = alias;
size_t resultlen;
size_t aliaslen;
const char *p;
size_t len;
_DIAGASSERT(dbname != NULL);
_DIAGASSERT(alias != NULL);
_DIAGASSERT(buf != NULL);
fp = fopen(dbname, "r");
if (fp == NULL)
goto quit;
aliaslen = strlen(alias);
while (/*CONSTCOND*/ 1) {
p = fgetln(fp, &len);
if (p == NULL)
goto quit; /* eof or error */
_DIAGASSERT(len != 0);
/* ignore terminating NL */
if (p[len - 1] == '\n')
len--;
/* ignore null line and comment */
if (len == 0 || p[0] == '#')
continue;
if (aliaslen > len)
continue;
if (memcmp(alias, p, aliaslen))
continue;
p += aliaslen;
len -= aliaslen;
if (len == 0 || !__is_ws(*p))
continue;
/* entry was found here */
break;
/* NOTREACHED */
}
/* skip white spaces */
do {
p++;
len--;
} while (len != 0 && __is_ws(*p));
if (len == 0)
goto quit;
/* count length of result */
resultlen = 0;
while (resultlen < len && !__is_ws(*p))
resultlen++;
/* check if space is enough */
if (bufsize < resultlen + 1)
goto quit;
memcpy(buf, p, resultlen);
((char *)buf)[resultlen] = 0;
result = buf;
quit:
if (fp)
fclose(fp);
return result;
}