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>
28 #define LINEBUF_MAX 4096
31 * Fetch a new line from the input stream and resize buffer if necessary
33 static void uci_getln(struct uci_context *ctx, int offset)
35 struct uci_parse_context *pctx = ctx->pctx;
39 if (pctx->buf == NULL) {
40 pctx->buf = uci_malloc(ctx, LINEBUF);
41 pctx->bufsz = LINEBUF;
49 p = fgets(p, pctx->bufsz - ofs, pctx->file);
54 if (pctx->buf[ofs - 1] == '\n') {
56 pctx->buf[ofs - 1] = 0;
60 if (pctx->bufsz > LINEBUF_MAX/2) {
61 pctx->reason = "line too long";
62 pctx->byte = LINEBUF_MAX;
63 UCI_THROW(ctx, UCI_ERR_PARSE);
67 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
72 * Clean up all extra memory used by the parser and exporter
74 static void uci_file_cleanup(struct uci_context *ctx)
76 struct uci_parse_context *pctx;
90 uci_free_package(pctx->package);
101 * parse a character escaped by '\'
102 * returns true if the escaped character is to be parsed
103 * returns false if the escaped character is to be ignored
105 static inline bool parse_backslash(struct uci_context *ctx, char **str)
110 /* undecoded backslash at the end of line, fetch the next line */
113 uci_getln(ctx, *str - ctx->pctx->buf);
117 /* FIXME: decode escaped char, necessary? */
122 * move the string pointer forward until a non-whitespace character or
125 static void skip_whitespace(struct uci_context *ctx, char **str)
128 while (**str && isspace(**str))
132 if (!parse_backslash(ctx, str))
137 static inline void addc(char **dest, char **src)
145 * parse a double quoted string argument from the command line
147 static void parse_double_quote(struct uci_context *ctx, char **str, char **target)
151 /* skip quote character */
154 while ((c = **str)) {
161 if (!parse_backslash(ctx, str))
169 ctx->pctx->reason = "unterminated \"";
170 ctx->pctx->byte = *str - ctx->pctx->buf;
171 UCI_THROW(ctx, UCI_ERR_PARSE);
175 * parse a single quoted string argument from the command line
177 static void parse_single_quote(struct uci_context *ctx, char **str, char **target)
180 /* skip quote character */
183 while ((c = **str)) {
193 ctx->pctx->reason = "unterminated '";
194 ctx->pctx->byte = *str - ctx->pctx->buf;
195 UCI_THROW(ctx, UCI_ERR_PARSE);
199 * parse a string from the command line and detect the quoting style
201 static void parse_str(struct uci_context *ctx, char **str, char **target)
206 parse_single_quote(ctx, str, target);
209 parse_double_quote(ctx, str, target);
214 if (!parse_backslash(ctx, str))
221 } while (**str && !isspace(**str));
225 * if the string was unquoted and we've stopped at a whitespace
226 * character, skip to the next one, because the whitespace will
227 * be overwritten by a null byte here
232 /* terminate the parsed string */
237 * extract the next argument from the command line
239 static char *next_arg(struct uci_context *ctx, char **str, bool required)
245 skip_whitespace(ctx, str);
246 parse_str(ctx, str, &ptr);
247 if (required && !*val) {
248 ctx->pctx->reason = "insufficient arguments";
249 ctx->pctx->byte = *str - ctx->pctx->buf;
250 UCI_THROW(ctx, UCI_ERR_PARSE);
257 * verify that the end of the line or command is reached.
258 * throw an error if extra arguments are given on the command line
260 static void assert_eol(struct uci_context *ctx, char **str)
264 tmp = next_arg(ctx, str, false);
266 ctx->pctx->reason = "too many arguments";
267 ctx->pctx->byte = tmp - ctx->pctx->buf;
268 UCI_THROW(ctx, UCI_ERR_PARSE);
273 * switch to a different config, either triggered by uci_load, or by a
274 * 'package <...>' statement in the import file
276 static void uci_switch_config(struct uci_context *ctx)
278 struct uci_parse_context *pctx;
279 struct uci_element *e;
285 /* add the last config to main config file list */
287 uci_list_add(&ctx->root, &pctx->package->e.list);
289 pctx->package = NULL;
290 pctx->section = NULL;
297 * if an older config under the same name exists, unload it
298 * ignore errors here, e.g. if the config was not found
300 UCI_TRAP_SAVE(ctx, ignore);
301 e = uci_lookup_list(ctx, &ctx->root, name);
303 uci_unload(ctx, uci_to_package(e));
304 UCI_TRAP_RESTORE(ctx);
308 pctx->package = uci_alloc_package(ctx, name);
312 * parse the 'package' uci command (next config package)
314 static void uci_parse_package(struct uci_context *ctx, char **str, bool single)
318 /* command string null-terminated by strtok */
319 *str += strlen(*str) + 1;
321 name = next_arg(ctx, str, true);
322 assert_eol(ctx, str);
326 ctx->pctx->name = name;
327 uci_switch_config(ctx);
331 * parse the 'config' uci command (open a section)
333 static void uci_parse_config(struct uci_context *ctx, char **str)
338 if (!ctx->pctx->package) {
339 if (!ctx->pctx->name) {
340 ctx->pctx->byte = *str - ctx->pctx->buf;
341 ctx->pctx->reason = "attempting to import a file without a package name";
342 UCI_THROW(ctx, UCI_ERR_PARSE);
344 uci_switch_config(ctx);
347 /* command string null-terminated by strtok */
348 *str += strlen(*str) + 1;
350 type = next_arg(ctx, str, true);
351 name = next_arg(ctx, str, false);
352 assert_eol(ctx, str);
353 ctx->pctx->section = uci_alloc_section(ctx->pctx->package, type, name);
357 * parse the 'option' uci command (open a value)
359 static void uci_parse_option(struct uci_context *ctx, char **str)
364 if (!ctx->pctx->section) {
365 ctx->pctx->byte = *str - ctx->pctx->buf;
366 ctx->pctx->reason = "option command found before the first section";
367 UCI_THROW(ctx, UCI_ERR_PARSE);
369 /* command string null-terminated by strtok */
370 *str += strlen(*str) + 1;
372 name = next_arg(ctx, str, true);
373 value = next_arg(ctx, str, true);
374 assert_eol(ctx, str);
375 uci_alloc_option(ctx->pctx->section, name, value);
380 * parse a complete input line, split up combined commands by ';'
382 static void uci_parse_line(struct uci_context *ctx, bool single)
384 struct uci_parse_context *pctx = ctx->pctx;
385 char *word, *brk = NULL;
387 for (word = strtok_r(pctx->buf, ";", &brk);
389 word = strtok_r(NULL, ";", &brk)) {
392 word = strtok_r(word, " \t", &pbrk);
396 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
397 uci_parse_package(ctx, &word, single);
400 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
401 uci_parse_config(ctx, &word);
404 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
405 uci_parse_option(ctx, &word);
408 pctx->reason = "unterminated command";
409 pctx->byte = word - pctx->buf;
410 UCI_THROW(ctx, UCI_ERR_PARSE);
416 /* max number of characters that escaping adds to the string */
417 #define UCI_QUOTE_ESCAPE "'\\''"
420 * escape an uci string for export
422 static char *uci_escape(struct uci_context *ctx, char *str)
428 ctx->bufsz = LINEBUF;
429 ctx->buf = malloc(LINEBUF);
433 p = strchr(str, '\'');
440 if (p + sizeof(UCI_QUOTE_ESCAPE) - str >= ctx->bufsz) {
442 ctx->buf = realloc(ctx->buf, ctx->bufsz);
444 UCI_THROW(ctx, UCI_ERR_MEM);
446 memcpy(&ctx->buf[pos], s, len);
449 strcpy(&ctx->buf[pos], UCI_QUOTE_ESCAPE);
450 pos += sizeof(UCI_QUOTE_ESCAPE);
452 } while ((p = strchr(s, '\'')));
459 * export a single config package to a file stream
461 static void uci_export_package(struct uci_package *p, FILE *stream, bool header)
463 struct uci_context *ctx = p->ctx;
464 struct uci_element *s, *o;
467 fprintf(stream, "package '%s'\n", uci_escape(ctx, p->e.name));
468 uci_foreach_element(&p->sections, s) {
469 struct uci_section *sec = uci_to_section(s);
470 fprintf(stream, "\nconfig '%s'", uci_escape(ctx, sec->type));
471 fprintf(stream, " '%s'\n", uci_escape(ctx, sec->e.name));
472 uci_foreach_element(&sec->options, o) {
473 struct uci_option *opt = uci_to_option(o);
474 fprintf(stream, "\toption '%s'", uci_escape(ctx, opt->e.name));
475 fprintf(stream, " '%s'\n", uci_escape(ctx, opt->value));
478 fprintf(stream, "\n");
481 int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header)
483 struct uci_element *e;
486 UCI_ASSERT(ctx, stream != NULL);
489 uci_export_package(package, stream, header);
493 uci_foreach_element(&ctx->root, e) {
494 uci_export_package(uci_to_package(e), stream, header);
500 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single)
502 struct uci_parse_context *pctx;
504 /* make sure no memory from previous parse attempts is leaked */
505 uci_file_cleanup(ctx);
507 pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
512 * If 'name' was supplied, assume that the supplied stream does not contain
513 * the appropriate 'package <name>' string to specify the config name
514 * NB: the config file can still override the package name
519 while (!feof(pctx->file)) {
522 uci_parse_line(ctx, single);
526 *package = pctx->package;
529 uci_switch_config(ctx);
531 /* no error happened, we can get rid of the parser context now */
532 uci_file_cleanup(ctx);
537 int uci_load(struct uci_context *ctx, const char *name, struct uci_package **package)
546 UCI_ASSERT(ctx, name != NULL);
551 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
554 /* absolute/relative path outside of /etc/config */
555 filename = uci_strdup(ctx, name);
556 name = strrchr(name, '/') + 1;
560 filename = uci_malloc(ctx, strlen(name) + sizeof(UCI_CONFDIR) + 2);
561 sprintf(filename, UCI_CONFDIR "/%s", name);
566 if ((stat(filename, &statbuf) < 0) ||
567 ((statbuf.st_mode & S_IFMT) != S_IFREG)) {
568 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
571 fd = open(filename, O_RDONLY);
573 UCI_THROW(ctx, UCI_ERR_IO);
575 if (flock(fd, LOCK_SH) < 0)
576 UCI_THROW(ctx, UCI_ERR_IO);
578 file = fdopen(fd, "r");
580 UCI_THROW(ctx, UCI_ERR_IO);
583 UCI_TRAP_SAVE(ctx, done);
584 uci_import(ctx, file, name, package, true);
585 UCI_TRAP_RESTORE(ctx);
588 (*package)->path = filename;
589 (*package)->confdir = confdir;
598 int uci_commit(struct uci_context *ctx, struct uci_package *p)
602 int err = UCI_ERR_IO;
605 UCI_ASSERT(ctx, p != NULL);
606 UCI_ASSERT(ctx, p->path != NULL);
608 fd = open(p->path, O_RDWR);
612 if (flock(fd, LOCK_EX) < 0)
620 UCI_TRAP_SAVE(ctx, done);
621 uci_export(ctx, f, p, false);
622 UCI_TRAP_RESTORE(ctx);
631 UCI_THROW(ctx, ctx->errno);
633 UCI_THROW(ctx, UCI_ERR_IO);
639 * This function returns the filename by returning the string
640 * after the last '/' character. By checking for a non-'\0'
641 * character afterwards, directories are ignored (glob marks
642 * those with a trailing '/'
644 static inline char *get_filename(char *path)
648 p = strrchr(path, '/');
655 char **uci_list_configs(struct uci_context *ctx)
662 if (glob(UCI_CONFDIR "/*", GLOB_MARK, NULL, &globbuf) != 0)
665 size = sizeof(char *) * (globbuf.gl_pathc + 1);
666 for(i = 0; i < globbuf.gl_pathc; i++) {
669 p = get_filename(globbuf.gl_pathv[i]);
673 size += strlen(p) + 1;
676 configs = malloc(size);
680 memset(configs, 0, size);
681 buf = (char *) &configs[globbuf.gl_pathc + 1];
682 for(i = 0; i < globbuf.gl_pathc; i++) {
685 p = get_filename(globbuf.gl_pathv[i]);
691 buf += strlen(buf) + 1;