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
20 #include <sys/types.h>
30 #define LINEBUF_MAX 4096
32 static void uci_parse_error(struct uci_context
*ctx
, char *pos
, char *reason
)
34 struct uci_parse_context
*pctx
= ctx
->pctx
;
36 pctx
->reason
= reason
;
37 pctx
->byte
= pos
- pctx
->buf
;
38 UCI_THROW(ctx
, UCI_ERR_PARSE
);
42 * Fetch a new line from the input stream and resize buffer if necessary
44 static void uci_getln(struct uci_context
*ctx
, int offset
)
46 struct uci_parse_context
*pctx
= ctx
->pctx
;
50 if (pctx
->buf
== NULL
) {
51 pctx
->buf
= uci_malloc(ctx
, LINEBUF
);
52 pctx
->bufsz
= LINEBUF
;
60 p
= fgets(p
, pctx
->bufsz
- ofs
, pctx
->file
);
65 if (pctx
->buf
[ofs
- 1] == '\n') {
67 pctx
->buf
[ofs
- 1] = 0;
71 if (pctx
->bufsz
> LINEBUF_MAX
/2)
72 uci_parse_error(ctx
, p
, "line too long");
75 pctx
->buf
= uci_realloc(ctx
, pctx
->buf
, pctx
->bufsz
);
80 * Clean up all extra memory used by the parser and exporter
82 static void uci_file_cleanup(struct uci_context
*ctx
)
84 struct uci_parse_context
*pctx
;
98 uci_free_package(&pctx
->package
);
107 * parse a character escaped by '\'
108 * returns true if the escaped character is to be parsed
109 * returns false if the escaped character is to be ignored
111 static inline bool parse_backslash(struct uci_context
*ctx
, char **str
)
116 /* undecoded backslash at the end of line, fetch the next line */
119 uci_getln(ctx
, *str
- ctx
->pctx
->buf
);
123 /* FIXME: decode escaped char, necessary? */
128 * move the string pointer forward until a non-whitespace character or
131 static void skip_whitespace(struct uci_context
*ctx
, char **str
)
134 while (**str
&& isspace(**str
))
138 if (!parse_backslash(ctx
, str
))
143 static inline void addc(char **dest
, char **src
)
151 * parse a double quoted string argument from the command line
153 static void parse_double_quote(struct uci_context
*ctx
, char **str
, char **target
)
157 /* skip quote character */
160 while ((c
= **str
)) {
167 if (!parse_backslash(ctx
, str
))
175 uci_parse_error(ctx
, *str
, "unterminated \"");
179 * parse a single quoted string argument from the command line
181 static void parse_single_quote(struct uci_context
*ctx
, char **str
, char **target
)
184 /* skip quote character */
187 while ((c
= **str
)) {
197 uci_parse_error(ctx
, *str
, "unterminated '");
201 * parse a string from the command line and detect the quoting style
203 static void parse_str(struct uci_context
*ctx
, char **str
, char **target
)
208 parse_single_quote(ctx
, str
, target
);
211 parse_double_quote(ctx
, str
, target
);
216 if (!parse_backslash(ctx
, str
))
223 } while (**str
&& !isspace(**str
));
227 * if the string was unquoted and we've stopped at a whitespace
228 * character, skip to the next one, because the whitespace will
229 * be overwritten by a null byte here
234 /* terminate the parsed string */
239 * extract the next argument from the command line
241 static char *next_arg(struct uci_context
*ctx
, char **str
, bool required
, bool name
)
247 skip_whitespace(ctx
, str
);
248 parse_str(ctx
, str
, &ptr
);
251 uci_parse_error(ctx
, *str
, "insufficient arguments");
255 if (name
&& !uci_validate_name(val
))
256 uci_parse_error(ctx
, val
, "invalid character in field");
263 * verify that the end of the line or command is reached.
264 * throw an error if extra arguments are given on the command line
266 static void assert_eol(struct uci_context
*ctx
, char **str
)
270 tmp
= next_arg(ctx
, str
, false, false);
272 uci_parse_error(ctx
, *str
, "too many arguments");
276 * switch to a different config, either triggered by uci_load, or by a
277 * 'package <...>' statement in the import file
279 static void uci_switch_config(struct uci_context
*ctx
)
281 struct uci_parse_context
*pctx
;
282 struct uci_element
*e
;
288 /* add the last config to main config file list */
290 uci_list_add(&ctx
->root
, &pctx
->package
->e
.list
);
292 pctx
->package
= NULL
;
293 pctx
->section
= NULL
;
300 * if an older config under the same name exists, unload it
301 * ignore errors here, e.g. if the config was not found
303 e
= uci_lookup_list(ctx
, &ctx
->root
, name
);
305 UCI_THROW(ctx
, UCI_ERR_DUPLICATE
);
306 pctx
->package
= uci_alloc_package(ctx
, name
);
310 * parse the 'package' uci command (next config package)
312 static void uci_parse_package(struct uci_context
*ctx
, char **str
, bool single
)
316 /* command string null-terminated by strtok */
317 *str
+= strlen(*str
) + 1;
319 name
= next_arg(ctx
, str
, true, true);
320 assert_eol(ctx
, str
);
324 ctx
->pctx
->name
= name
;
325 uci_switch_config(ctx
);
328 /* Based on an efficient hash function published by D. J. Bernstein */
329 static unsigned int djbhash(unsigned int hash
, char *str
)
331 int len
= strlen(str
);
338 for(i
= 0; i
< len
; i
++) {
339 hash
= ((hash
<< 5) + hash
) + str
[i
];
341 return (hash
& 0x7FFFFFFF);
344 /* fix up an unnamed section */
345 static void uci_fixup_section(struct uci_context
*ctx
, struct uci_section
*s
)
347 unsigned int hash
= ~0;
348 struct uci_element
*e
;
355 * Generate a name for unnamed sections. This is used as reference
356 * when locating or updating the section from apps/scripts.
357 * To make multiple concurrent versions somewhat safe for updating,
358 * the name is generated from a hash of its type and name/value
359 * pairs of its option, and it is prefixed by a counter value.
360 * If the order of the unnamed sections changes for some reason,
361 * updates to them will be rejected.
363 hash
= djbhash(hash
, s
->type
);
364 uci_foreach_element(&s
->options
, e
) {
365 hash
= djbhash(hash
, e
->name
);
366 hash
= djbhash(hash
, uci_to_option(e
)->value
);
368 sprintf(buf
, "cfg%02x%04x", ++s
->package
->n_section
, hash
% (1 << 16));
369 s
->e
.name
= uci_strdup(ctx
, buf
);
373 * parse the 'config' uci command (open a section)
375 static void uci_parse_config(struct uci_context
*ctx
, char **str
)
377 struct uci_parse_context
*pctx
= ctx
->pctx
;
381 uci_fixup_section(ctx
, ctx
->pctx
->section
);
382 if (!ctx
->pctx
->package
) {
383 if (!ctx
->pctx
->name
)
384 uci_parse_error(ctx
, *str
, "attempting to import a file without a package name");
386 uci_switch_config(ctx
);
389 /* command string null-terminated by strtok */
390 *str
+= strlen(*str
) + 1;
392 type
= next_arg(ctx
, str
, true, true);
393 name
= next_arg(ctx
, str
, false, true);
394 assert_eol(ctx
, str
);
397 UCI_TRAP_SAVE(ctx
, error
);
398 uci_set(ctx
, pctx
->package
, name
, NULL
, type
);
399 UCI_TRAP_RESTORE(ctx
);
402 UCI_THROW(ctx
, ctx
->errno
);
404 pctx
->section
= uci_alloc_section(pctx
->package
, type
, name
);
408 * parse the 'option' uci command (open a value)
410 static void uci_parse_option(struct uci_context
*ctx
, char **str
)
412 struct uci_parse_context
*pctx
= ctx
->pctx
;
417 uci_parse_error(ctx
, *str
, "option command found before the first section");
419 /* command string null-terminated by strtok */
420 *str
+= strlen(*str
) + 1;
422 name
= next_arg(ctx
, str
, true, true);
423 value
= next_arg(ctx
, str
, true, false);
424 assert_eol(ctx
, str
);
427 UCI_TRAP_SAVE(ctx
, error
);
428 uci_set(ctx
, pctx
->package
, pctx
->section
->e
.name
, name
, value
);
429 UCI_TRAP_RESTORE(ctx
);
432 UCI_THROW(ctx
, ctx
->errno
);
434 uci_alloc_option(pctx
->section
, name
, value
);
439 * parse a complete input line, split up combined commands by ';'
441 static void uci_parse_line(struct uci_context
*ctx
, bool single
)
443 struct uci_parse_context
*pctx
= ctx
->pctx
;
444 char *word
, *brk
= NULL
;
446 for (word
= strtok_r(pctx
->buf
, ";", &brk
);
448 word
= strtok_r(NULL
, ";", &brk
)) {
451 word
= strtok_r(word
, " \t", &pbrk
);
455 if ((word
[1] == 0) || !strcmp(word
+ 1, "ackage"))
456 uci_parse_package(ctx
, &word
, single
);
459 if ((word
[1] == 0) || !strcmp(word
+ 1, "onfig"))
460 uci_parse_config(ctx
, &word
);
463 if ((word
[1] == 0) || !strcmp(word
+ 1, "ption"))
464 uci_parse_option(ctx
, &word
);
467 uci_parse_error(ctx
, word
, "unterminated command");
473 /* max number of characters that escaping adds to the string */
474 #define UCI_QUOTE_ESCAPE "'\\''"
477 * escape an uci string for export
479 static char *uci_escape(struct uci_context
*ctx
, char *str
)
485 ctx
->bufsz
= LINEBUF
;
486 ctx
->buf
= malloc(LINEBUF
);
490 p
= strchr(str
, '\'');
497 if (p
+ sizeof(UCI_QUOTE_ESCAPE
) - str
>= ctx
->bufsz
) {
499 ctx
->buf
= realloc(ctx
->buf
, ctx
->bufsz
);
501 UCI_THROW(ctx
, UCI_ERR_MEM
);
503 memcpy(&ctx
->buf
[pos
], s
, len
);
506 strcpy(&ctx
->buf
[pos
], UCI_QUOTE_ESCAPE
);
507 pos
+= sizeof(UCI_QUOTE_ESCAPE
);
509 } while ((p
= strchr(s
, '\'')));
516 * export a single config package to a file stream
518 static void uci_export_package(struct uci_package
*p
, FILE *stream
, bool header
)
520 struct uci_context
*ctx
= p
->ctx
;
521 struct uci_element
*s
, *o
;
524 fprintf(stream
, "package '%s'\n", uci_escape(ctx
, p
->e
.name
));
525 uci_foreach_element(&p
->sections
, s
) {
526 struct uci_section
*sec
= uci_to_section(s
);
527 fprintf(stream
, "\nconfig '%s'", uci_escape(ctx
, sec
->type
));
528 if (!sec
->anonymous
|| (ctx
->flags
& UCI_FLAG_EXPORT_NAME
))
529 fprintf(stream
, " '%s'", uci_escape(ctx
, sec
->e
.name
));
530 fprintf(stream
, "\n");
531 uci_foreach_element(&sec
->options
, o
) {
532 struct uci_option
*opt
= uci_to_option(o
);
533 fprintf(stream
, "\toption '%s'", uci_escape(ctx
, opt
->e
.name
));
534 fprintf(stream
, " '%s'\n", uci_escape(ctx
, opt
->value
));
537 fprintf(stream
, "\n");
540 int uci_export(struct uci_context
*ctx
, FILE *stream
, struct uci_package
*package
, bool header
)
542 struct uci_element
*e
;
545 UCI_ASSERT(ctx
, stream
!= NULL
);
548 uci_export_package(package
, stream
, header
);
550 uci_foreach_element(&ctx
->root
, e
) {
551 uci_export_package(uci_to_package(e
), stream
, header
);
558 int uci_import(struct uci_context
*ctx
, FILE *stream
, const char *name
, struct uci_package
**package
, bool single
)
560 struct uci_parse_context
*pctx
;
563 /* make sure no memory from previous parse attempts is leaked */
564 uci_file_cleanup(ctx
);
566 pctx
= (struct uci_parse_context
*) uci_malloc(ctx
, sizeof(struct uci_parse_context
));
569 if (*package
&& single
) {
570 pctx
->package
= *package
;
575 * If 'name' was supplied, assume that the supplied stream does not contain
576 * the appropriate 'package <name>' string to specify the config name
577 * NB: the config file can still override the package name
582 while (!feof(pctx
->file
)) {
584 UCI_TRAP_SAVE(ctx
, error
);
586 uci_parse_line(ctx
, single
);
587 UCI_TRAP_RESTORE(ctx
);
590 if (ctx
->flags
& UCI_FLAG_PERROR
)
591 uci_perror(ctx
, NULL
);
592 if ((ctx
->errno
!= UCI_ERR_PARSE
) ||
593 (ctx
->flags
& UCI_FLAG_STRICT
))
594 UCI_THROW(ctx
, ctx
->errno
);
597 uci_fixup_section(ctx
, ctx
->pctx
->section
);
599 *package
= pctx
->package
;
601 pctx
->package
= NULL
;
604 uci_switch_config(ctx
);
606 /* no error happened, we can get rid of the parser context now */
607 uci_file_cleanup(ctx
);
613 * open a stream and go to the right position
615 * note: when opening for write and seeking to the beginning of
616 * the stream, truncate the file
618 static FILE *uci_open_stream(struct uci_context
*ctx
, const char *filename
, int pos
, bool write
, bool create
)
623 int mode
= (write
? O_RDWR
: O_RDONLY
);
628 if (!write
&& ((stat(filename
, &statbuf
) < 0) ||
629 ((statbuf
.st_mode
& S_IFMT
) != S_IFREG
))) {
630 UCI_THROW(ctx
, UCI_ERR_NOTFOUND
);
633 fd
= open(filename
, mode
, UCI_FILEMODE
);
637 if (flock(fd
, (write
? LOCK_EX
: LOCK_SH
)) < 0)
640 ret
= lseek(fd
, 0, pos
);
645 file
= fdopen(fd
, (write
? "w+" : "r"));
650 UCI_THROW(ctx
, UCI_ERR_IO
);
655 static void uci_close_stream(FILE *stream
)
667 static void uci_parse_history_line(struct uci_context
*ctx
, struct uci_package
*p
, char *buf
)
671 char *package
= NULL
;
672 char *section
= NULL
;
679 } else if (buf
[0] == '@') {
684 UCI_INTERNAL(uci_parse_tuple
, ctx
, buf
, &package
, §ion
, &option
, &value
);
685 if (!package
|| !section
|| (!delete && !value
))
687 if (strcmp(package
, p
->e
.name
) != 0)
689 if (!uci_validate_name(section
))
691 if (option
&& !uci_validate_name(option
))
695 UCI_INTERNAL(uci_rename
, ctx
, p
, section
, option
, value
);
697 UCI_INTERNAL(uci_delete
, ctx
, p
, section
, option
);
699 UCI_INTERNAL(uci_set
, ctx
, p
, section
, option
, value
);
703 UCI_THROW(ctx
, UCI_ERR_PARSE
);
706 static void uci_parse_history(struct uci_context
*ctx
, FILE *stream
, struct uci_package
*p
)
708 struct uci_parse_context
*pctx
;
710 /* make sure no memory from previous parse attempts is leaked */
711 uci_file_cleanup(ctx
);
713 pctx
= (struct uci_parse_context
*) uci_malloc(ctx
, sizeof(struct uci_parse_context
));
717 while (!feof(pctx
->file
)) {
723 * ignore parse errors in single lines, we want to preserve as much
724 * history as possible
726 UCI_TRAP_SAVE(ctx
, error
);
727 uci_parse_history_line(ctx
, p
, pctx
->buf
);
728 UCI_TRAP_RESTORE(ctx
);
733 /* no error happened, we can get rid of the parser context now */
734 uci_file_cleanup(ctx
);
737 static void uci_load_history(struct uci_context
*ctx
, struct uci_package
*p
, bool flush
)
739 char *filename
= NULL
;
744 if ((asprintf(&filename
, "%s/%s", UCI_SAVEDIR
, p
->e
.name
) < 0) || !filename
)
745 UCI_THROW(ctx
, UCI_ERR_MEM
);
747 UCI_TRAP_SAVE(ctx
, done
);
748 f
= uci_open_stream(ctx
, filename
, SEEK_SET
, flush
, false);
750 uci_parse_history(ctx
, f
, p
);
751 UCI_TRAP_RESTORE(ctx
);
756 ftruncate(fileno(f
), 0);
765 static char *uci_config_path(struct uci_context
*ctx
, const char *name
)
769 if (strchr(name
, '/'))
770 UCI_THROW(ctx
, UCI_ERR_INVAL
);
771 filename
= uci_malloc(ctx
, strlen(name
) + sizeof(UCI_CONFDIR
) + 2);
772 sprintf(filename
, UCI_CONFDIR
"/%s", name
);
777 int uci_load(struct uci_context
*ctx
, const char *name
, struct uci_package
**package
)
787 /* relative path outside of /etc/config */
789 UCI_THROW(ctx
, UCI_ERR_NOTFOUND
);
792 /* absolute path outside of /etc/config */
793 filename
= uci_strdup(ctx
, name
);
794 name
= strrchr(name
, '/') + 1;
798 /* config in /etc/config */
799 UCI_ASSERT(ctx
, uci_validate_name(name
));
800 filename
= uci_config_path(ctx
, name
);
805 file
= uci_open_stream(ctx
, filename
, SEEK_SET
, false, false);
807 UCI_TRAP_SAVE(ctx
, done
);
808 UCI_INTERNAL(uci_import
, ctx
, file
, name
, package
, true);
809 UCI_TRAP_RESTORE(ctx
);
812 (*package
)->path
= filename
;
813 (*package
)->confdir
= confdir
;
814 uci_load_history(ctx
, *package
, false);
818 uci_close_stream(file
);
822 int uci_save(struct uci_context
*ctx
, struct uci_package
*p
)
825 char *filename
= NULL
;
826 struct uci_element
*e
, *tmp
;
829 UCI_ASSERT(ctx
, p
!= NULL
);
832 * if the config file was outside of the /etc/config path,
833 * don't save the history to a file, update the real file
835 * does not modify the uci_package pointer
838 return uci_commit(ctx
, &p
, false);
840 if (uci_list_empty(&p
->history
))
843 if ((asprintf(&filename
, "%s/%s", UCI_SAVEDIR
, p
->e
.name
) < 0) || !filename
)
844 UCI_THROW(ctx
, UCI_ERR_MEM
);
847 UCI_TRAP_SAVE(ctx
, done
);
848 f
= uci_open_stream(ctx
, filename
, SEEK_END
, true, true);
849 UCI_TRAP_RESTORE(ctx
);
851 uci_foreach_element_safe(&p
->history
, tmp
, e
) {
852 struct uci_history
*h
= uci_to_history(e
);
854 if (h
->cmd
== UCI_CMD_REMOVE
)
856 else if (h
->cmd
== UCI_CMD_RENAME
)
859 fprintf(f
, "%s.%s", p
->e
.name
, h
->section
);
861 fprintf(f
, ".%s", e
->name
);
863 if (h
->cmd
== UCI_CMD_REMOVE
)
866 fprintf(f
, "=%s\n", h
->value
);
875 UCI_THROW(ctx
, ctx
->errno
);
880 int uci_commit(struct uci_context
*ctx
, struct uci_package
**package
, bool overwrite
)
882 struct uci_package
*p
;
888 UCI_ASSERT(ctx
, package
!= NULL
);
891 UCI_ASSERT(ctx
, p
!= NULL
);
894 p
->path
= uci_config_path(ctx
, p
->e
.name
);
896 UCI_THROW(ctx
, UCI_ERR_INVAL
);
900 /* open the config file for writing now, so that it is locked */
901 f
= uci_open_stream(ctx
, p
->path
, SEEK_SET
, true, true);
903 /* flush unsaved changes and reload from history file */
904 UCI_TRAP_SAVE(ctx
, done
);
907 name
= uci_strdup(ctx
, p
->e
.name
);
908 path
= uci_strdup(ctx
, p
->path
);
909 if (!uci_list_empty(&p
->history
))
910 UCI_INTERNAL(uci_save
, ctx
, p
);
911 uci_free_package(&p
);
912 uci_file_cleanup(ctx
);
913 UCI_INTERNAL(uci_import
, ctx
, f
, name
, &p
, true);
919 /* freed together with the uci_package */
922 /* check for updated history, just in case */
923 uci_load_history(ctx
, p
, true);
926 uci_load_history(ctx
, NULL
, true);
931 ftruncate(fileno(f
), 0);
933 uci_export(ctx
, f
, p
, false);
934 UCI_TRAP_RESTORE(ctx
);
943 UCI_THROW(ctx
, ctx
->errno
);
950 * This function returns the filename by returning the string
951 * after the last '/' character. By checking for a non-'\0'
952 * character afterwards, directories are ignored (glob marks
953 * those with a trailing '/'
955 static inline char *get_filename(char *path
)
959 p
= strrchr(path
, '/');
966 int uci_list_configs(struct uci_context
*ctx
, char ***list
)
975 if (glob(UCI_CONFDIR
"/*", GLOB_MARK
, NULL
, &globbuf
) != 0)
976 UCI_THROW(ctx
, UCI_ERR_NOTFOUND
);
978 size
= sizeof(char *) * (globbuf
.gl_pathc
+ 1);
979 for(i
= 0; i
< globbuf
.gl_pathc
; i
++) {
982 p
= get_filename(globbuf
.gl_pathv
[i
]);
986 size
+= strlen(p
) + 1;
989 configs
= uci_malloc(ctx
, size
);
990 buf
= (char *) &configs
[globbuf
.gl_pathc
+ 1];
991 for(i
= 0; i
< globbuf
.gl_pathc
; i
++) {
994 p
= get_filename(globbuf
.gl_pathv
[i
]);
1000 buf
+= strlen(buf
) + 1;