1 /* $NetBSD: aliasname.c,v 1.2 2005/02/09 21:35:46 kleink Exp $ */
2
3 /*-
4 * Copyright (c)2002 YAMAMOTO Takashi,
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28 #include <LibConfig.h>
29 #include <sys/EfiCdefs.h>
30 #if defined(LIBC_SCCS) && !defined(lint)
31 __RCSID("$NetBSD: aliasname.c,v 1.2 2005/02/09 21:35:46 kleink Exp $");
32 #endif /* LIBC_SCCS and not lint */
33
34 #include "namespace.h"
35 #include <assert.h>
36 #include <stdio.h>
37 #include <string.h>
38
39 #include "aliasname_local.h"
40
41 __inline int __is_ws(char);
42
__is_ws(char ch)43 __inline int __is_ws(char ch)
44 {
45
46 return (ch == ' ' || ch == '\t');
47 }
48
49 const char *
__unaliasname(const char * dbname,const char * alias,void * buf,size_t bufsize)50 __unaliasname(const char *dbname, const char *alias, void *buf, size_t bufsize)
51 {
52 FILE *fp = NULL;
53 const char *result = alias;
54 size_t resultlen;
55 size_t aliaslen;
56 const char *p;
57 size_t len;
58
59 _DIAGASSERT(dbname != NULL);
60 _DIAGASSERT(alias != NULL);
61 _DIAGASSERT(buf != NULL);
62
63 fp = fopen(dbname, "r");
64 if (fp == NULL)
65 goto quit;
66
67 aliaslen = strlen(alias);
68
69 while (/*CONSTCOND*/ 1) {
70 p = fgetln(fp, &len);
71 if (p == NULL)
72 goto quit; /* eof or error */
73
74 _DIAGASSERT(len != 0);
75
76 /* ignore terminating NL */
77 if (p[len - 1] == '\n')
78 len--;
79
80 /* ignore null line and comment */
81 if (len == 0 || p[0] == '#')
82 continue;
83
84 if (aliaslen > len)
85 continue;
86
87 if (memcmp(alias, p, aliaslen))
88 continue;
89
90 p += aliaslen;
91 len -= aliaslen;
92
93 if (len == 0 || !__is_ws(*p))
94 continue;
95
96 /* entry was found here */
97 break;
98
99 /* NOTREACHED */
100 }
101
102 /* skip white spaces */
103 do {
104 p++;
105 len--;
106 } while (len != 0 && __is_ws(*p));
107
108 if (len == 0)
109 goto quit;
110
111 /* count length of result */
112 resultlen = 0;
113 while (resultlen < len && !__is_ws(*p))
114 resultlen++;
115
116 /* check if space is enough */
117 if (bufsize < resultlen + 1)
118 goto quit;
119
120 memcpy(buf, p, resultlen);
121 ((char *)buf)[resultlen] = 0;
122 result = buf;
123
124 quit:
125 if (fp)
126 fclose(fp);
127
128 return result;
129 }
130