add .gitignore
[project/uci.git] / parse.c
1 /*
2 * libuci - Library for the Unified Configuration Interface
3 * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
4 *
5 * this program is free software; you can redistribute it and/or modify
6 * it under the terms of the gnu lesser general public license version 2.1
7 * as published by the free software foundation
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 */
14
15 /*
16 * This file contains the code for parsing uci config files
17 */
18
19 #include <ctype.h>
20
21 #define LINEBUF 128
22 #define LINEBUF_MAX 4096
23
24 /*
25 * Fetch a new line from the input stream and resize buffer if necessary
26 */
27 static void uci_getln(struct uci_context *ctx)
28 {
29 struct uci_parse_context *pctx = ctx->pctx;
30 char *p;
31 int ofs;
32
33 if (pctx->buf == NULL) {
34 pctx->buf = uci_malloc(ctx, LINEBUF);
35 pctx->bufsz = LINEBUF;
36 }
37
38 ofs = 0;
39 do {
40 p = &pctx->buf[ofs];
41 p[ofs] = 0;
42
43 p = fgets(p, pctx->bufsz - ofs, pctx->file);
44 if (!p || !p[ofs])
45 return;
46
47 ofs += strlen(p);
48 if (pctx->buf[ofs - 1] == '\n') {
49 pctx->line++;
50 pctx->buf[ofs - 1] = 0;
51 return;
52 }
53
54 if (pctx->bufsz > LINEBUF_MAX/2) {
55 pctx->byte = LINEBUF_MAX;
56 UCI_THROW(ctx, UCI_ERR_PARSE);
57 }
58
59 pctx->bufsz *= 2;
60 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
61 } while (1);
62 }
63
64 /*
65 * Clean up all extra memory used by the parser
66 */
67 static void uci_parse_cleanup(struct uci_context *ctx)
68 {
69 struct uci_parse_context *pctx;
70
71 pctx = ctx->pctx;
72 if (!pctx)
73 return;
74
75 if (pctx->buf)
76 free(pctx->buf);
77 if (pctx->file)
78 fclose(pctx->file);
79
80 free(pctx);
81 }
82
83 static void skip_whitespace(char **str)
84 {
85 while (**str && isspace(**str))
86 *str += 1;
87 }
88
89 static char *parse_double_quote(char **str)
90 {
91 char *val;
92
93 *str += 1;
94 val = *str;
95 while (**str) {
96
97 /* skip escaped characters */
98 if (**str == '\\') {
99 *str += 2;
100 continue;
101 }
102
103 /* check for the end of the quoted string */
104 if (**str == '"') {
105 **str = 0;
106 *str += 1;
107 return val;
108 }
109 *str += 1;
110 }
111
112 return NULL;
113 }
114
115 static char *parse_single_quote(char **str)
116 {
117 /* TODO: implement */
118 return NULL;
119 }
120
121 static char *parse_unquoted(char **str)
122 {
123 char *val;
124
125 val = *str;
126
127 while (**str && !isspace(**str))
128 *str += 1;
129 **str = 0;
130 *str += 1;
131
132 return val;
133 }
134
135 static char *next_arg(char **str)
136 {
137 skip_whitespace(str);
138
139 switch (**str) {
140 case '"':
141 return parse_double_quote(str);
142 case '\'':
143 return parse_single_quote(str);
144 case 0:
145 return NULL;
146 default:
147 return parse_unquoted(str);
148 }
149 }
150
151 static void uci_parse_config(struct uci_context *ctx, char **str)
152 {
153 char *type, *name;
154
155 *str += strlen(*str) + 1;
156
157 if (!*str) {
158 ctx->pctx->byte = *str - ctx->pctx->buf;
159 UCI_THROW(ctx, UCI_ERR_PARSE);
160 }
161
162 type = next_arg(str);
163 if (!type) {
164 ctx->pctx->byte = *str - ctx->pctx->buf;
165 UCI_THROW(ctx, UCI_ERR_PARSE);
166 }
167
168 name = next_arg(str);
169 DPRINTF("Section<%s>: %s\n", type, name);
170 }
171
172 static void uci_parse_option(struct uci_context *ctx, char **str)
173 {
174 char *name, *value;
175
176 *str += strlen(*str) + 1;
177
178 name = next_arg(str);
179 if (!name) {
180 ctx->pctx->byte = *str - ctx->pctx->buf;
181 UCI_THROW(ctx, UCI_ERR_PARSE);
182 }
183
184 value = next_arg(str);
185 if (!value) {
186 ctx->pctx->byte = *str - ctx->pctx->buf;
187 UCI_THROW(ctx, UCI_ERR_PARSE);
188 }
189
190 DPRINTF("\tOption: %s=\"%s\"\n", name, value);
191 }
192
193 static void uci_parse_line(struct uci_context *ctx)
194 {
195 struct uci_parse_context *pctx = ctx->pctx;
196 char *word, *brk;
197
198 for (word = strtok_r(pctx->buf, ";", &brk);
199 word;
200 word = strtok_r(NULL, ";", &brk)) {
201
202 char *pbrk;
203 word = strtok_r(word, " \t", &pbrk);
204
205 switch(word[0]) {
206 case 'c':
207 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
208 uci_parse_config(ctx, &word);
209 break;
210 case 'o':
211 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
212 uci_parse_option(ctx, &word);
213 break;
214 default:
215 pctx->byte = word - pctx->buf;
216 UCI_THROW(ctx, UCI_ERR_PARSE);
217 break;
218 }
219 }
220 }
221
222 int uci_parse(struct uci_context *ctx, const char *name)
223 {
224 struct uci_parse_context *pctx;
225
226 UCI_HANDLE_ERR(ctx);
227 UCI_ASSERT(ctx, name != NULL);
228
229 /* make sure no memory from previous parse attempts is leaked */
230 uci_parse_cleanup(ctx);
231
232 pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
233 ctx->pctx = pctx;
234
235 /* TODO: use /etc/config/ */
236 pctx->file = fopen(name, "r");
237 if (!pctx->file)
238 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
239
240 while (!feof(pctx->file)) {
241 uci_getln(ctx);
242 if (*(pctx->buf))
243 uci_parse_line(ctx);
244 }
245
246 /* if no error happened, we can get rid of the parser context now */
247 uci_parse_cleanup(ctx);
248
249 return 0;
250 }
251
252