1 /*	$NetBSD: libdm-string.c,v 1.1.1.2 2009/12/02 00:26:08 haad Exp $	*/
2 
3 /*
4  * Copyright (C) 2006-2007 Red Hat, Inc. All rights reserved.
5  *
6  * This file is part of the device-mapper userspace tools.
7  *
8  * This copyrighted material is made available to anyone wishing to use,
9  * modify, copy, or redistribute it subject to the terms and conditions
10  * of the GNU Lesser General Public License v.2.1.
11  *
12  * You should have received a copy of the GNU Lesser General Public License
13  * along with this program; if not, write to the Free Software Foundation,
14  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
15  */
16 
17 #include "dmlib.h"
18 #include "libdevmapper.h"
19 
20 #include <ctype.h>
21 
22 /*
23  * consume characters while they match the predicate function.
24  */
25 static char *_consume(char *buffer, int (*fn) (int))
26 {
27 	while (*buffer && fn(*buffer))
28 		buffer++;
29 
30 	return buffer;
31 }
32 
33 static int _isword(int c)
34 {
35 	return !isspace(c);
36 }
37 
38 /*
39  * Split buffer into NULL-separated words in argv.
40  * Returns number of words.
41  */
42 int dm_split_words(char *buffer, unsigned max,
43 		   unsigned ignore_comments __attribute((unused)),
44 		   char **argv)
45 {
46 	unsigned arg;
47 
48 	for (arg = 0; arg < max; arg++) {
49 		buffer = _consume(buffer, isspace);
50 		if (!*buffer)
51 			break;
52 
53 		argv[arg] = buffer;
54 		buffer = _consume(buffer, _isword);
55 
56 		if (*buffer) {
57 			*buffer = '\0';
58 			buffer++;
59 		}
60 	}
61 
62 	return arg;
63 }
64 
65 /*
66  * Remove hyphen quoting from a component of a name.
67  * NULL-terminates the component and returns start of next component.
68  */
69 static char *_unquote(char *component)
70 {
71 	char *c = component;
72 	char *o = c;
73 	char *r;
74 
75 	while (*c) {
76 		if (*(c + 1)) {
77 			if (*c == '-') {
78 				if (*(c + 1) == '-')
79 					c++;
80 				else
81 					break;
82 			}
83 		}
84 		*o = *c;
85 		o++;
86 		c++;
87 	}
88 
89 	r = (*c) ? c + 1 : c;
90 	*o = '\0';
91 
92 	return r;
93 }
94 
95 int dm_split_lvm_name(struct dm_pool *mem, const char *dmname,
96 		      char **vgname, char **lvname, char **layer)
97 {
98 	if (mem && !(*vgname = dm_pool_strdup(mem, dmname)))
99 		return 0;
100 
101 	_unquote(*layer = _unquote(*lvname = _unquote(*vgname)));
102 
103 	return 1;
104 }
105 
106 /*
107  * On error, up to glibc 2.0.6, snprintf returned -1 if buffer was too small;
108  * From glibc 2.1 it returns number of chars (excl. trailing null) that would
109  * have been written had there been room.
110  *
111  * dm_snprintf reverts to the old behaviour.
112  */
113 int dm_snprintf(char *buf, size_t bufsize, const char *format, ...)
114 {
115 	int n;
116 	va_list ap;
117 
118 	va_start(ap, format);
119 	n = vsnprintf(buf, bufsize, format, ap);
120 	va_end(ap);
121 
122 	if (n < 0 || ((unsigned) n + 1 > bufsize))
123 		return -1;
124 
125 	return n;
126 }
127 
128 char *dm_basename(const char *path)
129 {
130 	char *p = strrchr(path, '/');
131 
132 	return p ? p + 1 : (char *) path;
133 }
134 
135 int dm_asprintf(char **result, const char *format, ...)
136 {
137 	int n, ok = 0, size = 32;
138 	va_list ap;
139 	char *buf = dm_malloc(size);
140 
141 	*result = 0;
142 
143 	if (!buf)
144 		return -1;
145 
146 	while (!ok) {
147 		va_start(ap, format);
148 		n = vsnprintf(buf, size, format, ap);
149 		if (0 <= n && n < size)
150 			ok = 1;
151 		else {
152 			dm_free(buf);
153 			size *= 2;
154 			buf = dm_malloc(size);
155 			if (!buf)
156 				return -1;
157 		};
158 		va_end(ap);
159 	}
160 
161 	*result = dm_strdup(buf);
162 	dm_free(buf);
163 	return n + 1;
164 }
165