1 /* vi: set sw=4 ts=4: */
3 * config file parser helper
5 * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>
7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
8 * Also for use in uClibc (http://uclibc.org/) licensed under LGPLv2.1 or later.
12 //usage:#define parse_trivial_usage
13 //usage: "[-n MAXTOKENS] [-m MINTOKENS] [-d DELIMS] [-f FLAGS] FILE..."
14 //usage:#define parse_full_usage ""
19 #if defined ENABLE_PARSE && ENABLE_PARSE
20 int parse_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
21 int parse_main(int argc UNUSED_PARAM, char **argv)
23 const char *delims = "# \t";
24 unsigned flags = PARSE_NORMAL;
25 int mintokens = 0, ntokens = 128;
27 opt_complementary = "-1:n+:m+:f+";
28 getopt32(argv, "n:m:d:f:", &ntokens, &mintokens, &delims, &flags);
32 parser_t *p = config_open(*argv);
35 char **t = xmalloc(sizeof(char *) * ntokens);
36 while ((n = config_read(p, t, ntokens, mintokens, delims, flags)) != 0) {
37 for (int i = 0; i < n; ++i)
54 char *t[3]; // tokens placeholder
55 parser_t *p = config_open(filename);
58 while (config_read(p, t, 3, 0, delimiters, flags)) { // 1..3 tokens
60 bb_error_msg("TOKENS: [%s][%s][%s]", t[0], t[1], t[2]);
70 parser_t* FAST_FUNC config_open2(const char *filename, FILE* FAST_FUNC (*fopen_func)(const char *path))
75 fp = fopen_func(filename);
78 parser = xzalloc(sizeof(*parser));
83 parser_t* FAST_FUNC config_open(const char *filename)
85 return config_open2(filename, fopen_or_warn_stdin);
88 static void config_free_data(parser_t *parser)
92 if (PARSE_KEEP_COPY) { /* compile-time constant */
98 void FAST_FUNC config_close(parser_t *parser)
101 config_free_data(parser);
108 0. If parser is NULL return 0.
109 1. Read a line from config file. If nothing to read then return 0.
110 Handle continuation character. Advance lineno for each physical line.
111 Discard everything past comment character.
112 2. if PARSE_TRIM is set (default), remove leading and trailing delimiters.
113 3. If resulting line is empty goto 1.
114 4. Look for first delimiter. If !PARSE_COLLAPSE or !PARSE_TRIM is set then
115 remember the token as empty.
116 5. Else (default) if number of seen tokens is equal to max number of tokens
117 (token is the last one) and PARSE_GREEDY is set then the remainder
118 of the line is the last token.
119 Else (token is not last or PARSE_GREEDY is not set) just replace
120 first delimiter with '\0' thus delimiting the token.
121 6. Advance line pointer past the end of token. If number of seen tokens
122 is less than required number of tokens then goto 4.
123 7. Check the number of seen tokens is not less the min number of tokens.
124 Complain or die otherwise depending on PARSE_MIN_DIE.
125 8. Return the number of seen tokens.
127 mintokens > 0 make config_read() print error message if less than mintokens
128 (but more than 0) are found. Empty lines are always skipped (not warned about).
131 int FAST_FUNC config_read(parser_t *parser, char **tokens, unsigned flags, const char *delims)
134 int ntokens, mintokens;
137 ntokens = (uint8_t)flags;
138 mintokens = (uint8_t)(flags >> 8);
144 memset(tokens, 0, sizeof(tokens[0]) * ntokens);
145 config_free_data(parser);
147 /* Read one line (handling continuations with backslash) */
148 line = bb_get_chunk_with_continuation(parser->fp, &len, &parser->lineno);
153 /* Strip trailing line-feed if any */
154 if (len && line[len-1] == '\n')
157 /* Skip token in the start of line? */
158 if (flags & PARSE_TRIM)
159 line += strspn(line, delims + 1);
161 if (line[0] == '\0' || line[0] == delims[0])
164 if (flags & PARSE_KEEP_COPY)
165 parser->data = xstrdup(line);
167 /* Tokenize the line */
173 /* Combine remaining arguments? */
174 if ((t != (ntokens-1)) || !(flags & PARSE_GREEDY)) {
175 /* Vanilla token, find next delimiter */
176 line += strcspn(line, delims[0] ? delims : delims + 1);
178 /* Combining, find comment char if any */
179 line = strchrnul(line, delims[0]);
181 /* Trim any extra delimiters from the end */
182 if (flags & PARSE_TRIM) {
183 while (strchr(delims + 1, line[-1]) != NULL)
188 /* Token not terminated? */
189 if (*line == delims[0])
191 else if (*line != '\0')
194 #if 0 /* unused so far */
195 if (flags & PARSE_ESCAPE) {
196 strcpy_and_process_escape_sequences(tokens[t], tokens[t]);
199 /* Skip possible delimiters */
200 if (flags & PARSE_COLLAPSE)
201 line += strspn(line, delims + 1);
204 } while (*line && *line != delims[0] && t < ntokens);
207 bb_error_msg("bad line %u: %d tokens found, %d needed",
208 parser->lineno, t, mintokens);
209 if (flags & PARSE_MIN_DIE)
211 if (flags & PARSE_KEEP_COPY)