1 /* $NetBSD: lvm-string.c,v 1.1.1.1 2008/12/22 00:18:13 haad Exp $ */
2
3 /*
4 * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
5 * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
6 *
7 * This file is part of LVM2.
8 *
9 * This copyrighted material is made available to anyone wishing to use,
10 * modify, copy, or redistribute it subject to the terms and conditions
11 * of the GNU Lesser General Public License v.2.1.
12 *
13 * You should have received a copy of the GNU Lesser General Public License
14 * along with this program; if not, write to the Free Software Foundation,
15 * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
16 */
17
18 #include "lib.h"
19 #include "lvm-string.h"
20
21 #include <ctype.h>
22
emit_to_buffer(char ** buffer,size_t * size,const char * fmt,...)23 int emit_to_buffer(char **buffer, size_t *size, const char *fmt, ...)
24 {
25 int n;
26 va_list ap;
27
28 va_start(ap, fmt);
29 n = vsnprintf(*buffer, *size, fmt, ap);
30 va_end(ap);
31
32 if (n < 0 || ((size_t)n == *size))
33 return 0;
34
35 *buffer += n;
36 *size -= n;
37 return 1;
38 }
39
40 /*
41 * Count occurences of 'c' in 'str' until we reach a null char.
42 *
43 * Returns:
44 * len - incremented for each char we encounter.
45 * count - number of occurrences of 'c' and 'c2'.
46 */
_count_chars(const char * str,size_t * len,int * count,const int c1,const int c2)47 static void _count_chars(const char *str, size_t *len, int *count,
48 const int c1, const int c2)
49 {
50 const char *ptr;
51
52 for (ptr = str; *ptr; ptr++, (*len)++)
53 if (*ptr == c1 || *ptr == c2)
54 (*count)++;
55 }
56
57 /*
58 * Count occurences of 'c' in 'str' of length 'size'.
59 *
60 * Returns:
61 * Number of occurrences of 'c'
62 */
count_chars(const char * str,size_t len,const int c)63 unsigned count_chars(const char *str, size_t len, const int c)
64 {
65 size_t i;
66 unsigned count = 0;
67
68 for (i = 0; i < len; i++)
69 if (str[i] == c)
70 count++;
71
72 return count;
73 }
74
75 /*
76 * Length of string after escaping double quotes and backslashes.
77 */
escaped_len(const char * str)78 size_t escaped_len(const char *str)
79 {
80 size_t len = 1;
81 int count = 0;
82
83 _count_chars(str, &len, &count, '\"', '\\');
84
85 return count + len;
86 }
87
88 /*
89 * Copies a string, quoting orig_char with quote_char.
90 * Optionally also quote quote_char.
91 */
_quote_characters(char ** out,const char * src,const int orig_char,const int quote_char,int quote_quote_char)92 static void _quote_characters(char **out, const char *src,
93 const int orig_char, const int quote_char,
94 int quote_quote_char)
95 {
96 while (*src) {
97 if (*src == orig_char ||
98 (*src == quote_char && quote_quote_char))
99 *(*out)++ = quote_char;
100
101 *(*out)++ = *src++;
102 }
103 }
104
105 /*
106 * Unquote orig_char in string.
107 * Also unquote quote_char.
108 */
_unquote_characters(char * src,const int orig_char,const int quote_char)109 static void _unquote_characters(char *src, const int orig_char,
110 const int quote_char)
111 {
112 char *out = src;
113
114 while (*src) {
115 if (*src == quote_char &&
116 (*(src + 1) == orig_char || *(src + 1) == quote_char))
117 src++;
118
119 *out++ = *src++;
120 }
121
122 *out = '\0';
123 }
124
125 /*
126 * Copies a string, quoting hyphens with hyphens.
127 */
_quote_hyphens(char ** out,const char * src)128 static void _quote_hyphens(char **out, const char *src)
129 {
130 return _quote_characters(out, src, '-', '-', 0);
131 }
132
133 /*
134 * <vg>-<lv>-<layer> or if !layer just <vg>-<lv>.
135 */
build_dm_name(struct dm_pool * mem,const char * vgname,const char * lvname,const char * layer)136 char *build_dm_name(struct dm_pool *mem, const char *vgname,
137 const char *lvname, const char *layer)
138 {
139 size_t len = 1;
140 int hyphens = 1;
141 char *r, *out;
142
143 _count_chars(vgname, &len, &hyphens, '-', 0);
144 _count_chars(lvname, &len, &hyphens, '-', 0);
145
146 if (layer && *layer) {
147 _count_chars(layer, &len, &hyphens, '-', 0);
148 hyphens++;
149 }
150
151 len += hyphens;
152
153 if (!(r = dm_pool_alloc(mem, len))) {
154 log_error("build_dm_name: Allocation failed for %" PRIsize_t
155 " for %s %s %s.", len, vgname, lvname, layer);
156 return NULL;
157 }
158
159 out = r;
160 _quote_hyphens(&out, vgname);
161 *out++ = '-';
162 _quote_hyphens(&out, lvname);
163
164 if (layer && *layer) {
165 /* No hyphen if the layer begins with _ e.g. _mlog */
166 if (*layer != '_')
167 *out++ = '-';
168 _quote_hyphens(&out, layer);
169 }
170 *out = '\0';
171
172 return r;
173 }
174
175 /*
176 * Copies a string, quoting double quotes with backslashes.
177 */
escape_double_quotes(char * out,const char * src)178 char *escape_double_quotes(char *out, const char *src)
179 {
180 char *buf = out;
181
182 _quote_characters(&buf, src, '\"', '\\', 1);
183 *buf = '\0';
184
185 return out;
186 }
187
188 /*
189 * Undo quoting in situ.
190 */
unescape_double_quotes(char * src)191 void unescape_double_quotes(char *src)
192 {
193 _unquote_characters(src, '\"', '\\');
194 }
195
196 /*
197 * Device layer names are all of the form <vg>-<lv>-<layer>, any
198 * other hyphens that appear in these names are quoted with yet
199 * another hyphen. The top layer of any device has no layer
200 * name. eg, vg0-lvol0.
201 */
validate_name(const char * n)202 int validate_name(const char *n)
203 {
204 register char c;
205 register int len = 0;
206
207 if (!n || !*n)
208 return 0;
209
210 /* Hyphen used as VG-LV separator - ambiguity if LV starts with it */
211 if (*n == '-')
212 return 0;
213
214 if (!strcmp(n, ".") || !strcmp(n, ".."))
215 return 0;
216
217 while ((len++, c = *n++))
218 if (!isalnum(c) && c != '.' && c != '_' && c != '-' && c != '+')
219 return 0;
220
221 if (len > NAME_LEN)
222 return 0;
223
224 return 1;
225 }
226