2 * libuci - Library for the Unified Configuration Interface
3 * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
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
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.
16 * This file contains the code for parsing uci config files
19 #include <sys/types.h>
26 #define LINEBUF_MAX 4096
29 * Fetch a new line from the input stream and resize buffer if necessary
31 static void uci_getln(struct uci_context *ctx, int offset)
33 struct uci_parse_context *pctx = ctx->pctx;
37 if (pctx->buf == NULL) {
38 pctx->buf = uci_malloc(ctx, LINEBUF);
39 pctx->bufsz = LINEBUF;
47 p = fgets(p, pctx->bufsz - ofs, pctx->file);
52 if (pctx->buf[ofs - 1] == '\n') {
54 pctx->buf[ofs - 1] = 0;
58 if (pctx->bufsz > LINEBUF_MAX/2) {
59 pctx->reason = "line too long";
60 pctx->byte = LINEBUF_MAX;
61 UCI_THROW(ctx, UCI_ERR_PARSE);
65 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
70 * Clean up all extra memory used by the parser
72 static void uci_parse_cleanup(struct uci_context *ctx)
74 struct uci_parse_context *pctx;
82 uci_list_del(&pctx->cfg->list);
83 uci_drop_config(pctx->cfg);
94 * parse a character escaped by '\'
95 * returns true if the escaped character is to be parsed
96 * returns false if the escaped character is to be ignored
98 static inline bool parse_backslash(struct uci_context *ctx, char **str)
103 /* undecoded backslash at the end of line, fetch the next line */
106 uci_getln(ctx, *str - ctx->pctx->buf);
110 /* FIXME: decode escaped char, necessary? */
115 * move the string pointer forward until a non-whitespace character or
118 static void skip_whitespace(struct uci_context *ctx, char **str)
121 while (**str && isspace(**str))
125 if (!parse_backslash(ctx, str))
130 static inline void addc(char **dest, char **src)
138 * parse a double quoted string argument from the command line
140 static void parse_double_quote(struct uci_context *ctx, char **str, char **target)
144 /* skip quote character */
147 while ((c = **str)) {
154 if (!parse_backslash(ctx, str))
162 ctx->pctx->reason = "unterminated \"";
163 ctx->pctx->byte = *str - ctx->pctx->buf;
164 UCI_THROW(ctx, UCI_ERR_PARSE);
168 * parse a single quoted string argument from the command line
170 static void parse_single_quote(struct uci_context *ctx, char **str, char **target)
173 /* skip quote character */
176 while ((c = **str)) {
186 ctx->pctx->reason = "unterminated '";
187 ctx->pctx->byte = *str - ctx->pctx->buf;
188 UCI_THROW(ctx, UCI_ERR_PARSE);
192 * parse a string from the command line and detect the quoting style
194 static void parse_str(struct uci_context *ctx, char **str, char **target)
199 parse_single_quote(ctx, str, target);
202 parse_double_quote(ctx, str, target);
207 if (!parse_backslash(ctx, str))
214 } while (**str && !isspace(**str));
218 * if the string was unquoted and we've stopped at a whitespace
219 * character, skip to the next one, because the whitespace will
220 * be overwritten by a null byte here
225 /* terminate the parsed string */
230 * extract the next argument from the command line
232 static char *next_arg(struct uci_context *ctx, char **str, bool required)
238 skip_whitespace(ctx, str);
239 parse_str(ctx, str, &ptr);
240 if (required && !*val) {
241 ctx->pctx->reason = "insufficient arguments";
242 ctx->pctx->byte = *str - ctx->pctx->buf;
243 UCI_THROW(ctx, UCI_ERR_PARSE);
246 return uci_strdup(ctx, val);
250 * verify that the end of the line or command is reached.
251 * throw an error if extra arguments are given on the command line
253 static void assert_eol(struct uci_context *ctx, char **str)
257 tmp = next_arg(ctx, str, false);
259 ctx->pctx->reason = "too many arguments";
260 ctx->pctx->byte = tmp - ctx->pctx->buf;
261 UCI_THROW(ctx, UCI_ERR_PARSE);
266 * switch to a different config, either triggered by uci_load, or by a
267 * 'package <...>' statement in the import file
269 static void uci_switch_config(struct uci_context *ctx)
271 struct uci_parse_context *pctx;
277 /* add the last config to main config file list */
279 uci_list_add(&ctx->root, &pctx->cfg->list);
282 pctx->section = NULL;
289 * if an older config under the same name exists, unload it
290 * ignore errors here, e.g. if the config was not found
292 UCI_TRAP_SAVE(ctx, ignore);
293 uci_unload(ctx, name);
294 UCI_TRAP_RESTORE(ctx);
298 pctx->cfg = uci_alloc_config(ctx, name);
302 * parse the 'package' uci command (next config package)
304 static void uci_parse_package(struct uci_context *ctx, char **str)
308 /* command string null-terminated by strtok */
309 *str += strlen(*str) + 1;
311 UCI_TRAP_SAVE(ctx, error);
312 name = next_arg(ctx, str, true);
313 assert_eol(ctx, str);
314 ctx->pctx->name = name;
315 uci_switch_config(ctx);
316 UCI_TRAP_RESTORE(ctx);
322 UCI_THROW(ctx, ctx->errno);
326 * parse the 'config' uci command (open a section)
328 static void uci_parse_config(struct uci_context *ctx, char **str)
333 if (!ctx->pctx->cfg) {
334 if (!ctx->pctx->name) {
335 ctx->pctx->byte = *str - ctx->pctx->buf;
336 ctx->pctx->reason = "attempting to import a file without a package name";
337 UCI_THROW(ctx, UCI_ERR_PARSE);
339 uci_switch_config(ctx);
342 /* command string null-terminated by strtok */
343 *str += strlen(*str) + 1;
345 UCI_TRAP_SAVE(ctx, error);
346 type = next_arg(ctx, str, true);
347 name = next_arg(ctx, str, false);
348 assert_eol(ctx, str);
349 ctx->pctx->section = uci_add_section(ctx->pctx->cfg, type, name);
350 UCI_TRAP_RESTORE(ctx);
358 UCI_THROW(ctx, ctx->errno);
362 * parse the 'option' uci command (open a value)
364 static void uci_parse_option(struct uci_context *ctx, char **str)
369 if (!ctx->pctx->section) {
370 ctx->pctx->byte = *str - ctx->pctx->buf;
371 ctx->pctx->reason = "option command found before the first section";
372 UCI_THROW(ctx, UCI_ERR_PARSE);
374 /* command string null-terminated by strtok */
375 *str += strlen(*str) + 1;
377 UCI_TRAP_SAVE(ctx, error);
378 name = next_arg(ctx, str, true);
379 value = next_arg(ctx, str, true);
380 assert_eol(ctx, str);
381 uci_add_option(ctx->pctx->section, name, value);
382 UCI_TRAP_RESTORE(ctx);
390 UCI_THROW(ctx, ctx->errno);
395 * parse a complete input line, split up combined commands by ';'
397 static void uci_parse_line(struct uci_context *ctx)
399 struct uci_parse_context *pctx = ctx->pctx;
402 for (word = strtok_r(pctx->buf, ";", &brk);
404 word = strtok_r(NULL, ";", &brk)) {
407 word = strtok_r(word, " \t", &pbrk);
411 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
412 uci_parse_package(ctx, &word);
415 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
416 uci_parse_config(ctx, &word);
419 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
420 uci_parse_option(ctx, &word);
423 pctx->reason = "unterminated command";
424 pctx->byte = word - pctx->buf;
425 UCI_THROW(ctx, UCI_ERR_PARSE);
431 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_config **cfg)
433 struct uci_parse_context *pctx;
435 /* make sure no memory from previous parse attempts is leaked */
436 uci_parse_cleanup(ctx);
438 pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
443 * If 'name' was supplied, assume that the supplied stream does not contain
444 * the appropriate 'package <name>' string to specify the config name
445 * NB: the config file can still override the package name
450 while (!feof(pctx->file)) {
460 uci_switch_config(ctx);
462 /* no error happened, we can get rid of the parser context now */
463 uci_parse_cleanup(ctx);
468 int uci_load(struct uci_context *ctx, const char *name, struct uci_config **cfg)
476 UCI_ASSERT(ctx, name != NULL);
484 /* absolute/relative path outside of /etc/config */
485 filename = (char *) name;
489 filename = uci_malloc(ctx, strlen(name) + sizeof(UCI_CONFDIR) + 2);
490 sprintf(filename, UCI_CONFDIR "/%s", name);
495 if ((stat(filename, &statbuf) < 0) ||
496 ((statbuf.st_mode & S_IFMT) != S_IFREG)) {
497 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
500 file = fopen(filename, "r");
501 if (filename != name)
505 UCI_THROW(ctx, UCI_ERR_IO);
507 return uci_import(ctx, file, name, cfg);