diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /lib/parser.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'lib/parser.c')
-rw-r--r-- | lib/parser.c | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/lib/parser.c b/lib/parser.c new file mode 100644 index 000000000000..7ad2a48abc5e --- /dev/null +++ b/lib/parser.c | |||
@@ -0,0 +1,220 @@ | |||
1 | /* | ||
2 | * lib/parser.c - simple parser for mount, etc. options. | ||
3 | * | ||
4 | * This source code is licensed under the GNU General Public License, | ||
5 | * Version 2. See the file COPYING for more details. | ||
6 | */ | ||
7 | |||
8 | #include <linux/ctype.h> | ||
9 | #include <linux/module.h> | ||
10 | #include <linux/parser.h> | ||
11 | #include <linux/slab.h> | ||
12 | #include <linux/string.h> | ||
13 | |||
14 | /** | ||
15 | * match_one: - Determines if a string matches a simple pattern | ||
16 | * @s: the string to examine for presense of the pattern | ||
17 | * @p: the string containing the pattern | ||
18 | * @args: array of %MAX_OPT_ARGS &substring_t elements. Used to return match | ||
19 | * locations. | ||
20 | * | ||
21 | * Description: Determines if the pattern @p is present in string @s. Can only | ||
22 | * match extremely simple token=arg style patterns. If the pattern is found, | ||
23 | * the location(s) of the arguments will be returned in the @args array. | ||
24 | */ | ||
25 | static int match_one(char *s, char *p, substring_t args[]) | ||
26 | { | ||
27 | char *meta; | ||
28 | int argc = 0; | ||
29 | |||
30 | if (!p) | ||
31 | return 1; | ||
32 | |||
33 | while(1) { | ||
34 | int len = -1; | ||
35 | meta = strchr(p, '%'); | ||
36 | if (!meta) | ||
37 | return strcmp(p, s) == 0; | ||
38 | |||
39 | if (strncmp(p, s, meta-p)) | ||
40 | return 0; | ||
41 | |||
42 | s += meta - p; | ||
43 | p = meta + 1; | ||
44 | |||
45 | if (isdigit(*p)) | ||
46 | len = simple_strtoul(p, &p, 10); | ||
47 | else if (*p == '%') { | ||
48 | if (*s++ != '%') | ||
49 | return 0; | ||
50 | p++; | ||
51 | continue; | ||
52 | } | ||
53 | |||
54 | if (argc >= MAX_OPT_ARGS) | ||
55 | return 0; | ||
56 | |||
57 | args[argc].from = s; | ||
58 | switch (*p++) { | ||
59 | case 's': | ||
60 | if (strlen(s) == 0) | ||
61 | return 0; | ||
62 | else if (len == -1 || len > strlen(s)) | ||
63 | len = strlen(s); | ||
64 | args[argc].to = s + len; | ||
65 | break; | ||
66 | case 'd': | ||
67 | simple_strtol(s, &args[argc].to, 0); | ||
68 | goto num; | ||
69 | case 'u': | ||
70 | simple_strtoul(s, &args[argc].to, 0); | ||
71 | goto num; | ||
72 | case 'o': | ||
73 | simple_strtoul(s, &args[argc].to, 8); | ||
74 | goto num; | ||
75 | case 'x': | ||
76 | simple_strtoul(s, &args[argc].to, 16); | ||
77 | num: | ||
78 | if (args[argc].to == args[argc].from) | ||
79 | return 0; | ||
80 | break; | ||
81 | default: | ||
82 | return 0; | ||
83 | } | ||
84 | s = args[argc].to; | ||
85 | argc++; | ||
86 | } | ||
87 | } | ||
88 | |||
89 | /** | ||
90 | * match_token: - Find a token (and optional args) in a string | ||
91 | * @s: the string to examine for token/argument pairs | ||
92 | * @table: match_table_t describing the set of allowed option tokens and the | ||
93 | * arguments that may be associated with them. Must be terminated with a | ||
94 | * &struct match_token whose pattern is set to the NULL pointer. | ||
95 | * @args: array of %MAX_OPT_ARGS &substring_t elements. Used to return match | ||
96 | * locations. | ||
97 | * | ||
98 | * Description: Detects which if any of a set of token strings has been passed | ||
99 | * to it. Tokens can include up to MAX_OPT_ARGS instances of basic c-style | ||
100 | * format identifiers which will be taken into account when matching the | ||
101 | * tokens, and whose locations will be returned in the @args array. | ||
102 | */ | ||
103 | int match_token(char *s, match_table_t table, substring_t args[]) | ||
104 | { | ||
105 | struct match_token *p; | ||
106 | |||
107 | for (p = table; !match_one(s, p->pattern, args) ; p++) | ||
108 | ; | ||
109 | |||
110 | return p->token; | ||
111 | } | ||
112 | |||
113 | /** | ||
114 | * match_number: scan a number in the given base from a substring_t | ||
115 | * @s: substring to be scanned | ||
116 | * @result: resulting integer on success | ||
117 | * @base: base to use when converting string | ||
118 | * | ||
119 | * Description: Given a &substring_t and a base, attempts to parse the substring | ||
120 | * as a number in that base. On success, sets @result to the integer represented | ||
121 | * by the string and returns 0. Returns either -ENOMEM or -EINVAL on failure. | ||
122 | */ | ||
123 | static int match_number(substring_t *s, int *result, int base) | ||
124 | { | ||
125 | char *endp; | ||
126 | char *buf; | ||
127 | int ret; | ||
128 | |||
129 | buf = kmalloc(s->to - s->from + 1, GFP_KERNEL); | ||
130 | if (!buf) | ||
131 | return -ENOMEM; | ||
132 | memcpy(buf, s->from, s->to - s->from); | ||
133 | buf[s->to - s->from] = '\0'; | ||
134 | *result = simple_strtol(buf, &endp, base); | ||
135 | ret = 0; | ||
136 | if (endp == buf) | ||
137 | ret = -EINVAL; | ||
138 | kfree(buf); | ||
139 | return ret; | ||
140 | } | ||
141 | |||
142 | /** | ||
143 | * match_int: - scan a decimal representation of an integer from a substring_t | ||
144 | * @s: substring_t to be scanned | ||
145 | * @result: resulting integer on success | ||
146 | * | ||
147 | * Description: Attempts to parse the &substring_t @s as a decimal integer. On | ||
148 | * success, sets @result to the integer represented by the string and returns 0. | ||
149 | * Returns either -ENOMEM or -EINVAL on failure. | ||
150 | */ | ||
151 | int match_int(substring_t *s, int *result) | ||
152 | { | ||
153 | return match_number(s, result, 0); | ||
154 | } | ||
155 | |||
156 | /** | ||
157 | * match_octal: - scan an octal representation of an integer from a substring_t | ||
158 | * @s: substring_t to be scanned | ||
159 | * @result: resulting integer on success | ||
160 | * | ||
161 | * Description: Attempts to parse the &substring_t @s as an octal integer. On | ||
162 | * success, sets @result to the integer represented by the string and returns | ||
163 | * 0. Returns either -ENOMEM or -EINVAL on failure. | ||
164 | */ | ||
165 | int match_octal(substring_t *s, int *result) | ||
166 | { | ||
167 | return match_number(s, result, 8); | ||
168 | } | ||
169 | |||
170 | /** | ||
171 | * match_hex: - scan a hex representation of an integer from a substring_t | ||
172 | * @s: substring_t to be scanned | ||
173 | * @result: resulting integer on success | ||
174 | * | ||
175 | * Description: Attempts to parse the &substring_t @s as a hexadecimal integer. | ||
176 | * On success, sets @result to the integer represented by the string and | ||
177 | * returns 0. Returns either -ENOMEM or -EINVAL on failure. | ||
178 | */ | ||
179 | int match_hex(substring_t *s, int *result) | ||
180 | { | ||
181 | return match_number(s, result, 16); | ||
182 | } | ||
183 | |||
184 | /** | ||
185 | * match_strcpy: - copies the characters from a substring_t to a string | ||
186 | * @to: string to copy characters to. | ||
187 | * @s: &substring_t to copy | ||
188 | * | ||
189 | * Description: Copies the set of characters represented by the given | ||
190 | * &substring_t @s to the c-style string @to. Caller guarantees that @to is | ||
191 | * large enough to hold the characters of @s. | ||
192 | */ | ||
193 | void match_strcpy(char *to, substring_t *s) | ||
194 | { | ||
195 | memcpy(to, s->from, s->to - s->from); | ||
196 | to[s->to - s->from] = '\0'; | ||
197 | } | ||
198 | |||
199 | /** | ||
200 | * match_strdup: - allocate a new string with the contents of a substring_t | ||
201 | * @s: &substring_t to copy | ||
202 | * | ||
203 | * Description: Allocates and returns a string filled with the contents of | ||
204 | * the &substring_t @s. The caller is responsible for freeing the returned | ||
205 | * string with kfree(). | ||
206 | */ | ||
207 | char *match_strdup(substring_t *s) | ||
208 | { | ||
209 | char *p = kmalloc(s->to - s->from + 1, GFP_KERNEL); | ||
210 | if (p) | ||
211 | match_strcpy(p, s); | ||
212 | return p; | ||
213 | } | ||
214 | |||
215 | EXPORT_SYMBOL(match_token); | ||
216 | EXPORT_SYMBOL(match_int); | ||
217 | EXPORT_SYMBOL(match_octal); | ||
218 | EXPORT_SYMBOL(match_hex); | ||
219 | EXPORT_SYMBOL(match_strcpy); | ||
220 | EXPORT_SYMBOL(match_strdup); | ||