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 Lesser General Public License for more details.
16 * This file contains the code for parsing uci config files
20 #include <sys/types.h>
34 #include "uci_internal.h"
39 * Fetch a new line from the input stream and resize buffer if necessary
41 __private void uci_getln(struct uci_context *ctx, int offset)
43 struct uci_parse_context *pctx = ctx->pctx;
47 if (pctx->buf == NULL) {
48 pctx->buf = uci_malloc(ctx, LINEBUF);
49 pctx->bufsz = LINEBUF;
51 /* It takes 2 slots for fgets to read 1 char. */
52 if (offset >= pctx->bufsz - 1) {
54 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
62 p = fgets(p, pctx->bufsz - ofs, pctx->file);
67 if (pctx->buf[ofs - 1] == '\n') {
73 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
78 * parse a character escaped by '\'
79 * returns true if the escaped character is to be parsed
80 * returns false if the escaped character is to be ignored
82 static bool parse_backslash(struct uci_context *ctx)
84 struct uci_parse_context *pctx = ctx->pctx;
89 /* undecoded backslash at the end of line, fetch the next line */
90 if (!pctx_cur_char(pctx) ||
91 pctx_cur_char(pctx) == '\n' ||
92 (pctx_cur_char(pctx) == '\r' &&
93 pctx_char(pctx, pctx_pos(pctx) + 1) == '\n' &&
94 !pctx_char(pctx, pctx_pos(pctx) + 2))) {
95 uci_getln(ctx, pctx->pos);
99 /* FIXME: decode escaped char, necessary? */
104 * move the string pointer forward until a non-whitespace character or
107 static void skip_whitespace(struct uci_context *ctx)
109 struct uci_parse_context *pctx = ctx->pctx;
111 while (pctx_cur_char(pctx) && isspace(pctx_cur_char(pctx)))
115 static inline void addc(struct uci_context *ctx, int *pos_dest, int *pos_src)
117 struct uci_parse_context *pctx = ctx->pctx;
119 pctx_char(pctx, *pos_dest) = pctx_char(pctx, *pos_src);
125 * parse a double quoted string argument from the command line
127 static void parse_double_quote(struct uci_context *ctx, int *target)
129 struct uci_parse_context *pctx = ctx->pctx;
132 /* skip quote character */
136 c = pctx_cur_char(pctx);
142 /* Multi-line str value */
143 uci_getln(ctx, pctx->pos);
144 if (!pctx_cur_char(pctx)) {
145 uci_parse_error(ctx, "EOF with unterminated \"");
149 if (!parse_backslash(ctx))
153 addc(ctx, target, &pctx->pos);
160 * parse a single quoted string argument from the command line
162 static void parse_single_quote(struct uci_context *ctx, int *target)
164 struct uci_parse_context *pctx = ctx->pctx;
166 /* skip quote character */
170 c = pctx_cur_char(pctx);
176 /* Multi-line str value */
177 uci_getln(ctx, pctx->pos);
178 if (!pctx_cur_char(pctx))
179 uci_parse_error(ctx, "EOF with unterminated '");
183 addc(ctx, target, &pctx->pos);
189 * parse a string from the command line and detect the quoting style
191 static void parse_str(struct uci_context *ctx, int *target)
193 struct uci_parse_context *pctx = ctx->pctx;
196 switch(pctx_cur_char(pctx)) {
198 parse_single_quote(ctx, target);
201 parse_double_quote(ctx, target);
204 pctx_cur_char(pctx) = 0;
212 if (!parse_backslash(ctx))
216 addc(ctx, target, &pctx->pos);
219 } while (pctx_cur_char(pctx) && !isspace(pctx_cur_char(pctx)));
223 * if the string was unquoted and we've stopped at a whitespace
224 * character, skip to the next one, because the whitespace will
225 * be overwritten by a null byte here
227 if (pctx_cur_char(pctx) && next)
230 /* terminate the parsed string */
231 pctx_char(pctx, *target) = 0;
235 * extract the next argument from the command line
237 static int next_arg(struct uci_context *ctx, bool required, bool name, bool package)
239 struct uci_parse_context *pctx = ctx->pctx;
242 skip_whitespace(ctx);
243 val = ptr = pctx_pos(pctx);
244 if (pctx_cur_char(pctx) == ';') {
245 pctx_cur_char(pctx) = 0;
248 parse_str(ctx, &ptr);
250 if (!pctx_char(pctx, val)) {
252 uci_parse_error(ctx, "insufficient arguments");
256 if (name && !uci_validate_str(pctx_str(pctx, val), name, package))
257 uci_parse_error(ctx, "invalid character in name field");
263 int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result)
268 UCI_ASSERT(ctx, str != NULL);
269 UCI_ASSERT(ctx, result != NULL);
271 if (ctx->pctx && (ctx->pctx->file != stream))
275 uci_alloc_parse_context(ctx);
277 ctx->pctx->file = stream;
283 ofs_result = next_arg(ctx, false, false, false);
284 *result = pctx_str(ctx->pctx, ofs_result);
285 *str = pctx_cur_str(ctx->pctx);
291 uci_fill_ptr(struct uci_context *ctx, struct uci_ptr *ptr, struct uci_element *e)
293 UCI_ASSERT(ctx, ptr != NULL);
294 UCI_ASSERT(ctx, e != NULL);
296 memset(ptr, 0, sizeof(struct uci_ptr));
298 case UCI_TYPE_OPTION:
299 ptr->o = uci_to_option(e);
301 case UCI_TYPE_SECTION:
302 ptr->s = uci_to_section(e);
304 case UCI_TYPE_PACKAGE:
305 ptr->p = uci_to_package(e);
308 UCI_THROW(ctx, UCI_ERR_INVAL);
312 ptr->option = ptr->o->e.name;
313 ptr->s = ptr->o->section;
315 ptr->section = ptr->s->e.name;
316 ptr->p = ptr->s->package;
318 ptr->package = ptr->p->e.name;
320 ptr->flags |= UCI_LOOKUP_DONE;
328 * verify that the end of the line or command is reached.
329 * throw an error if extra arguments are given on the command line
331 static void assert_eol(struct uci_context *ctx)
336 skip_whitespace(ctx);
337 ofs_tmp = next_arg(ctx, false, false, false);
338 tmp = pctx_str(ctx->pctx, ofs_tmp);
339 if (*tmp && (ctx->flags & UCI_FLAG_STRICT))
340 uci_parse_error(ctx, "too many arguments");
344 * switch to a different config, either triggered by uci_load, or by a
345 * 'package <...>' statement in the import file
347 static void uci_switch_config(struct uci_context *ctx)
349 struct uci_parse_context *pctx;
350 struct uci_element *e;
356 /* add the last config to main config file list */
358 pctx->package->backend = ctx->backend;
359 uci_list_add(&ctx->root, &pctx->package->e.list);
361 pctx->package = NULL;
362 pctx->section = NULL;
369 * if an older config under the same name exists, unload it
370 * ignore errors here, e.g. if the config was not found
372 e = uci_lookup_list(&ctx->root, name);
374 UCI_THROW(ctx, UCI_ERR_DUPLICATE);
375 pctx->package = uci_alloc_package(ctx, name);
379 * parse the 'package' uci command (next config package)
381 static void uci_parse_package(struct uci_context *ctx, bool single)
383 struct uci_parse_context *pctx = ctx->pctx;
387 /* command string null-terminated by strtok */
388 pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
390 ofs_name = next_arg(ctx, true, true, true);
391 name = pctx_str(pctx, ofs_name);
396 ctx->pctx->name = name;
397 uci_switch_config(ctx);
401 * parse the 'config' uci command (open a section)
403 static void uci_parse_config(struct uci_context *ctx)
405 struct uci_parse_context *pctx = ctx->pctx;
406 struct uci_element *e;
408 int ofs_name, ofs_type;
412 if (!ctx->pctx->package) {
413 if (!ctx->pctx->name)
414 uci_parse_error(ctx, "attempting to import a file without a package name");
416 uci_switch_config(ctx);
419 /* command string null-terminated by strtok */
420 pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
422 ofs_type = next_arg(ctx, true, false, false);
423 type = pctx_str(pctx, ofs_type);
424 if (!uci_validate_type(type))
425 uci_parse_error(ctx, "invalid character in type field");
427 ofs_name = next_arg(ctx, false, true, false);
428 type = pctx_str(pctx, ofs_type);
429 name = pctx_str(pctx, ofs_name);
432 if (!name || !name[0]) {
433 ctx->internal = !pctx->merge;
434 UCI_NESTED(uci_add_section, ctx, pctx->package, type, &pctx->section);
436 uci_fill_ptr(ctx, &ptr, &pctx->package->e);
437 e = uci_lookup_list(&pctx->package->sections, name);
439 ptr.s = uci_to_section(e);
441 if ((ctx->flags & UCI_FLAG_STRICT) && strcmp(ptr.s->type, type))
442 uci_parse_error(ctx, "section of different type overwrites prior section with same name");
448 ctx->internal = !pctx->merge;
449 UCI_NESTED(uci_set, ctx, &ptr);
450 pctx->section = uci_to_section(ptr.last);
455 * parse the 'option' uci command (open a value)
457 static void uci_parse_option(struct uci_context *ctx, bool list)
459 struct uci_parse_context *pctx = ctx->pctx;
460 struct uci_element *e;
462 int ofs_name, ofs_value;
467 uci_parse_error(ctx, "option/list command found before the first section");
469 /* command string null-terminated by strtok */
470 pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
472 ofs_name = next_arg(ctx, true, true, false);
473 ofs_value = next_arg(ctx, false, false, false);
474 name = pctx_str(pctx, ofs_name);
475 value = pctx_str(pctx, ofs_value);
478 uci_fill_ptr(ctx, &ptr, &pctx->section->e);
479 e = uci_lookup_list(&pctx->section->options, name);
481 ptr.o = uci_to_option(e);
485 ctx->internal = !pctx->merge;
487 UCI_NESTED(uci_add_list, ctx, &ptr);
489 UCI_NESTED(uci_set, ctx, &ptr);
493 * parse a complete input line, split up combined commands by ';'
495 static void uci_parse_line(struct uci_context *ctx, bool single)
497 struct uci_parse_context *pctx = ctx->pctx;
500 /* Skip whitespace characters at the start of line */
501 skip_whitespace(ctx);
503 word = strtok(pctx_cur_str(pctx), " \t");
512 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
513 uci_parse_package(ctx, single);
518 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
519 uci_parse_config(ctx);
524 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
525 uci_parse_option(ctx, false);
530 if ((word[1] == 0) || !strcmp(word + 1, "ist"))
531 uci_parse_option(ctx, true);
540 uci_parse_error(ctx, "invalid command");
544 /* max number of characters that escaping adds to the string */
545 #define UCI_QUOTE_ESCAPE "'\\''"
548 * escape an uci string for export
550 static const char *uci_escape(struct uci_context *ctx, const char *str)
556 ctx->bufsz = LINEBUF;
557 ctx->buf = malloc(LINEBUF);
566 end = strchr(str, '\'');
568 end = str + strlen(str);
571 /* make sure that we have enough room in the buffer */
572 while (ofs + len + sizeof(UCI_QUOTE_ESCAPE) + 1 > ctx->bufsz) {
574 ctx->buf = uci_realloc(ctx, ctx->buf, ctx->bufsz);
577 /* copy the string until the character before the quote */
578 memcpy(&ctx->buf[ofs], str, len);
581 /* end of string? return the buffer */
585 memcpy(&ctx->buf[ofs], UCI_QUOTE_ESCAPE, sizeof(UCI_QUOTE_ESCAPE));
586 ofs += strlen(&ctx->buf[ofs]);
595 * export a single config package to a file stream
597 static void uci_export_package(struct uci_package *p, FILE *stream, bool header)
599 struct uci_context *ctx = p->ctx;
600 struct uci_element *s, *o, *i;
603 fprintf(stream, "package %s\n", uci_escape(ctx, p->e.name));
604 uci_foreach_element(&p->sections, s) {
605 struct uci_section *sec = uci_to_section(s);
606 fprintf(stream, "\nconfig %s", uci_escape(ctx, sec->type));
607 if (!sec->anonymous || (ctx->flags & UCI_FLAG_EXPORT_NAME))
608 fprintf(stream, " '%s'", uci_escape(ctx, sec->e.name));
609 fprintf(stream, "\n");
610 uci_foreach_element(&sec->options, o) {
611 struct uci_option *opt = uci_to_option(o);
613 case UCI_TYPE_STRING:
614 fprintf(stream, "\toption %s", uci_escape(ctx, opt->e.name));
615 fprintf(stream, " '%s'\n", uci_escape(ctx, opt->v.string));
618 uci_foreach_element(&opt->v.list, i) {
619 fprintf(stream, "\tlist %s", uci_escape(ctx, opt->e.name));
620 fprintf(stream, " '%s'\n", uci_escape(ctx, i->name));
624 fprintf(stream, "\t# unknown type for option '%s'\n", uci_escape(ctx, opt->e.name));
629 fprintf(stream, "\n");
632 int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header)
634 struct uci_element *e;
637 UCI_ASSERT(ctx, stream != NULL);
640 uci_export_package(package, stream, header);
642 uci_foreach_element(&ctx->root, e) {
643 uci_export_package(uci_to_package(e), stream, header);
650 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single)
652 struct uci_parse_context *pctx;
655 /* make sure no memory from previous parse attempts is leaked */
658 uci_alloc_parse_context(ctx);
661 if (package && *package && single) {
662 pctx->package = *package;
667 * If 'name' was supplied, assume that the supplied stream does not contain
668 * the appropriate 'package <name>' string to specify the config name
669 * NB: the config file can still override the package name
672 UCI_ASSERT(ctx, uci_validate_package(name));
676 while (!feof(pctx->file)) {
679 UCI_TRAP_SAVE(ctx, error);
681 uci_parse_line(ctx, single);
682 UCI_TRAP_RESTORE(ctx);
685 if (ctx->flags & UCI_FLAG_PERROR)
686 uci_perror(ctx, NULL);
687 if ((ctx->err != UCI_ERR_PARSE) ||
688 (ctx->flags & UCI_FLAG_STRICT))
689 UCI_THROW(ctx, ctx->err);
692 if (!pctx->package && name)
693 uci_switch_config(ctx);
695 *package = pctx->package;
697 pctx->package = NULL;
700 uci_switch_config(ctx);
702 /* no error happened, we can get rid of the parser context now */
709 static char *uci_config_path(struct uci_context *ctx, const char *name)
713 UCI_ASSERT(ctx, uci_validate_package(name));
714 filename = uci_malloc(ctx, strlen(name) + strlen(ctx->confdir) + 2);
715 sprintf(filename, "%s/%s", ctx->confdir, name);
720 static void uci_file_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
722 struct uci_package *p = *package;
723 FILE *f1, *f2 = NULL;
726 char *filename = NULL;
727 bool do_rename = false;
732 p->path = uci_config_path(ctx, p->e.name);
734 UCI_THROW(ctx, UCI_ERR_INVAL);
737 if ((asprintf(&filename, "%s/.%s.uci-XXXXXX", ctx->confdir, p->e.name) < 0) || !filename)
738 UCI_THROW(ctx, UCI_ERR_MEM);
740 /* open the config file for writing now, so that it is locked */
741 f1 = uci_open_stream(ctx, p->path, NULL, SEEK_SET, true, true);
743 /* flush unsaved changes and reload from delta file */
744 UCI_TRAP_SAVE(ctx, done);
747 name = uci_strdup(ctx, p->e.name);
748 path = uci_strdup(ctx, p->path);
749 /* dump our own changes to the delta file */
750 if (!uci_list_empty(&p->delta))
751 UCI_INTERNAL(uci_save, ctx, p);
754 * other processes might have modified the config
755 * as well. dump and reload
757 uci_free_package(&p);
759 UCI_INTERNAL(uci_import, ctx, f1, name, &p, true);
765 /* freed together with the uci_package */
770 if (!uci_load_delta(ctx, p, true))
774 fd = mkstemp(filename);
776 UCI_THROW(ctx, UCI_ERR_IO);
778 if ((flock(fd, LOCK_EX) < 0) && (errno != ENOSYS))
779 UCI_THROW(ctx, UCI_ERR_IO);
781 if (lseek(fd, 0, SEEK_SET) < 0)
782 UCI_THROW(ctx, UCI_ERR_IO);
784 f2 = fdopen(fd, "w+");
786 UCI_THROW(ctx, UCI_ERR_IO);
788 uci_export(ctx, f2, p, false);
792 uci_close_stream(f2);
796 UCI_TRAP_RESTORE(ctx);
801 uci_close_stream(f1);
803 path = realpath(p->path, NULL);
804 if (!path || rename(filename, path)) {
806 UCI_THROW(ctx, UCI_ERR_IO);
812 UCI_THROW(ctx, ctx->err);
817 * This function returns the filename by returning the string
818 * after the last '/' character. By checking for a non-'\0'
819 * character afterwards, directories are ignored (glob marks
820 * those with a trailing '/'
822 static inline char *get_filename(char *path)
826 p = strrchr(path, '/');
833 static char **uci_list_config_files(struct uci_context *ctx)
837 int size, i, j, skipped;
841 dir = uci_malloc(ctx, strlen(ctx->confdir) + 1 + sizeof("/*"));
842 sprintf(dir, "%s/*", ctx->confdir);
843 if (glob(dir, GLOB_MARK, NULL, &globbuf) != 0) {
845 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
848 size = sizeof(char *) * (globbuf.gl_pathc + 1);
850 for(i = 0; i < globbuf.gl_pathc; i++) {
853 p = get_filename(globbuf.gl_pathv[i]);
859 size += strlen(p) + 1;
862 configs = uci_malloc(ctx, size - skipped);
863 buf = (char *) &configs[globbuf.gl_pathc + 1 - skipped];
865 for(i = 0; i < globbuf.gl_pathc; i++) {
868 p = get_filename(globbuf.gl_pathv[i]);
872 if (!uci_validate_package(p))
877 buf += strlen(buf) + 1;
884 static struct uci_package *uci_file_load(struct uci_context *ctx, const char *name)
886 struct uci_package *package = NULL;
893 /* relative path outside of /etc/config */
895 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
898 /* absolute path outside of /etc/config */
899 filename = uci_strdup(ctx, name);
900 name = strrchr(name, '/') + 1;
904 /* config in /etc/config */
905 filename = uci_config_path(ctx, name);
910 UCI_TRAP_SAVE(ctx, done);
911 file = uci_open_stream(ctx, filename, NULL, SEEK_SET, false, false);
913 UCI_INTERNAL(uci_import, ctx, file, name, &package, true);
914 UCI_TRAP_RESTORE(ctx);
917 package->path = filename;
918 package->has_delta = confdir;
919 uci_load_delta(ctx, package, false);
923 uci_close_stream(file);
926 UCI_THROW(ctx, ctx->err);
931 __private UCI_BACKEND(uci_file_backend, "file",
932 .load = uci_file_load,
933 .commit = uci_file_commit,
934 .list_configs = uci_list_config_files,