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 and exporter
72 static void uci_file_cleanup(struct uci_context *ctx)
74 struct uci_parse_context *pctx;
88 uci_list_del(&pctx->package->list);
89 uci_drop_config(pctx->package);
100 * parse a character escaped by '\'
101 * returns true if the escaped character is to be parsed
102 * returns false if the escaped character is to be ignored
104 static inline bool parse_backslash(struct uci_context *ctx, char **str)
109 /* undecoded backslash at the end of line, fetch the next line */
112 uci_getln(ctx, *str - ctx->pctx->buf);
116 /* FIXME: decode escaped char, necessary? */
121 * move the string pointer forward until a non-whitespace character or
124 static void skip_whitespace(struct uci_context *ctx, char **str)
127 while (**str && isspace(**str))
131 if (!parse_backslash(ctx, str))
136 static inline void addc(char **dest, char **src)
144 * parse a double quoted string argument from the command line
146 static void parse_double_quote(struct uci_context *ctx, char **str, char **target)
150 /* skip quote character */
153 while ((c = **str)) {
160 if (!parse_backslash(ctx, str))
168 ctx->pctx->reason = "unterminated \"";
169 ctx->pctx->byte = *str - ctx->pctx->buf;
170 UCI_THROW(ctx, UCI_ERR_PARSE);
174 * parse a single quoted string argument from the command line
176 static void parse_single_quote(struct uci_context *ctx, char **str, char **target)
179 /* skip quote character */
182 while ((c = **str)) {
192 ctx->pctx->reason = "unterminated '";
193 ctx->pctx->byte = *str - ctx->pctx->buf;
194 UCI_THROW(ctx, UCI_ERR_PARSE);
198 * parse a string from the command line and detect the quoting style
200 static void parse_str(struct uci_context *ctx, char **str, char **target)
205 parse_single_quote(ctx, str, target);
208 parse_double_quote(ctx, str, target);
213 if (!parse_backslash(ctx, str))
220 } while (**str && !isspace(**str));
224 * if the string was unquoted and we've stopped at a whitespace
225 * character, skip to the next one, because the whitespace will
226 * be overwritten by a null byte here
231 /* terminate the parsed string */
236 * extract the next argument from the command line
238 static char *next_arg(struct uci_context *ctx, char **str, bool required)
244 skip_whitespace(ctx, str);
245 parse_str(ctx, str, &ptr);
246 if (required && !*val) {
247 ctx->pctx->reason = "insufficient arguments";
248 ctx->pctx->byte = *str - ctx->pctx->buf;
249 UCI_THROW(ctx, UCI_ERR_PARSE);
252 return uci_strdup(ctx, val);
256 * verify that the end of the line or command is reached.
257 * throw an error if extra arguments are given on the command line
259 static void assert_eol(struct uci_context *ctx, char **str)
263 tmp = next_arg(ctx, str, false);
265 ctx->pctx->reason = "too many arguments";
266 ctx->pctx->byte = tmp - ctx->pctx->buf;
267 UCI_THROW(ctx, UCI_ERR_PARSE);
272 * switch to a different config, either triggered by uci_load, or by a
273 * 'package <...>' statement in the import file
275 static void uci_switch_config(struct uci_context *ctx)
277 struct uci_parse_context *pctx;
283 /* add the last config to main config file list */
285 uci_list_add(&ctx->root, &pctx->package->list);
287 pctx->package = NULL;
288 pctx->section = NULL;
295 * if an older config under the same name exists, unload it
296 * ignore errors here, e.g. if the config was not found
298 UCI_TRAP_SAVE(ctx, ignore);
299 uci_unload(ctx, name);
300 UCI_TRAP_RESTORE(ctx);
304 pctx->package = uci_alloc_config(ctx, name);
308 * parse the 'package' uci command (next config package)
310 static void uci_parse_package(struct uci_context *ctx, char **str)
314 /* command string null-terminated by strtok */
315 *str += strlen(*str) + 1;
317 UCI_TRAP_SAVE(ctx, error);
318 name = next_arg(ctx, str, true);
319 assert_eol(ctx, str);
320 ctx->pctx->name = name;
321 uci_switch_config(ctx);
322 UCI_TRAP_RESTORE(ctx);
328 UCI_THROW(ctx, ctx->errno);
332 * parse the 'config' uci command (open a section)
334 static void uci_parse_config(struct uci_context *ctx, char **str)
339 if (!ctx->pctx->package) {
340 if (!ctx->pctx->name) {
341 ctx->pctx->byte = *str - ctx->pctx->buf;
342 ctx->pctx->reason = "attempting to import a file without a package name";
343 UCI_THROW(ctx, UCI_ERR_PARSE);
345 uci_switch_config(ctx);
348 /* command string null-terminated by strtok */
349 *str += strlen(*str) + 1;
351 UCI_TRAP_SAVE(ctx, error);
352 type = next_arg(ctx, str, true);
353 name = next_arg(ctx, str, false);
354 assert_eol(ctx, str);
355 ctx->pctx->section = uci_add_section(ctx->pctx->package, type, name);
356 UCI_TRAP_RESTORE(ctx);
364 UCI_THROW(ctx, ctx->errno);
368 * parse the 'option' uci command (open a value)
370 static void uci_parse_option(struct uci_context *ctx, char **str)
375 if (!ctx->pctx->section) {
376 ctx->pctx->byte = *str - ctx->pctx->buf;
377 ctx->pctx->reason = "option command found before the first section";
378 UCI_THROW(ctx, UCI_ERR_PARSE);
380 /* command string null-terminated by strtok */
381 *str += strlen(*str) + 1;
383 UCI_TRAP_SAVE(ctx, error);
384 name = next_arg(ctx, str, true);
385 value = next_arg(ctx, str, true);
386 assert_eol(ctx, str);
387 uci_add_option(ctx->pctx->section, name, value);
388 UCI_TRAP_RESTORE(ctx);
396 UCI_THROW(ctx, ctx->errno);
401 * parse a complete input line, split up combined commands by ';'
403 static void uci_parse_line(struct uci_context *ctx)
405 struct uci_parse_context *pctx = ctx->pctx;
408 for (word = strtok_r(pctx->buf, ";", &brk);
410 word = strtok_r(NULL, ";", &brk)) {
413 word = strtok_r(word, " \t", &pbrk);
417 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
418 uci_parse_package(ctx, &word);
421 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
422 uci_parse_config(ctx, &word);
425 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
426 uci_parse_option(ctx, &word);
429 pctx->reason = "unterminated command";
430 pctx->byte = word - pctx->buf;
431 UCI_THROW(ctx, UCI_ERR_PARSE);
437 /* max number of characters that escaping adds to the string */
438 #define UCI_QUOTE_ESCAPE "'\\'"
441 * escape an uci string for export
443 static char *uci_escape(struct uci_context *ctx, char *str)
449 ctx->bufsz = LINEBUF;
450 ctx->buf = malloc(LINEBUF);
454 p = strchr(str, '\'');
461 if (p + sizeof(UCI_QUOTE_ESCAPE) - str >= ctx->bufsz) {
463 ctx->buf = realloc(ctx->buf, ctx->bufsz);
465 UCI_THROW(ctx, UCI_ERR_MEM);
467 memcpy(&ctx->buf[pos], s, len);
470 strcpy(&ctx->buf[pos], UCI_QUOTE_ESCAPE);
471 pos += sizeof(UCI_QUOTE_ESCAPE);
473 } while ((p = strchr(s, '\'')));
480 * export a single config package to a file stream
482 static void uci_export_config(struct uci_package *package, FILE *stream)
484 struct uci_context *ctx = package->ctx;
485 struct uci_section *s;
486 struct uci_option *o;
488 fprintf(stream, "package '%s'\n", uci_escape(ctx, package->name));
489 uci_foreach_entry(section, &package->sections, s) {
490 fprintf(stream, "\nconfig '%s'", uci_escape(ctx, s->type));
491 fprintf(stream, " '%s'\n", uci_escape(ctx, s->name));
492 uci_foreach_entry(option, &s->options, o) {
493 fprintf(stream, "\toption '%s'", uci_escape(ctx, o->name));
494 fprintf(stream, " '%s'\n", uci_escape(ctx, o->value));
497 fprintf(stream, "\n");
500 int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package)
503 UCI_ASSERT(ctx, stream != NULL);
506 uci_export_config(package, stream);
510 uci_foreach_entry(package, &ctx->root, package) {
511 uci_export_config(package, stream);
517 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package)
519 struct uci_parse_context *pctx;
521 /* make sure no memory from previous parse attempts is leaked */
522 uci_file_cleanup(ctx);
524 pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
529 * If 'name' was supplied, assume that the supplied stream does not contain
530 * the appropriate 'package <name>' string to specify the config name
531 * NB: the config file can still override the package name
536 while (!feof(pctx->file)) {
543 *package = pctx->package;
546 uci_switch_config(ctx);
548 /* no error happened, we can get rid of the parser context now */
549 uci_file_cleanup(ctx);
554 int uci_load(struct uci_context *ctx, const char *name, struct uci_package **package)
562 UCI_ASSERT(ctx, name != NULL);
570 /* absolute/relative path outside of /etc/config */
571 filename = (char *) name;
575 filename = uci_malloc(ctx, strlen(name) + sizeof(UCI_CONFDIR) + 2);
576 sprintf(filename, UCI_CONFDIR "/%s", name);
581 if ((stat(filename, &statbuf) < 0) ||
582 ((statbuf.st_mode & S_IFMT) != S_IFREG)) {
583 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
586 file = fopen(filename, "r");
587 if (filename != name)
591 UCI_THROW(ctx, UCI_ERR_IO);
593 return uci_import(ctx, file, name, package);