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>
33 #include "uci_internal.h"
36 #define LINEBUF_MAX 4096
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') {
72 if (pctx->bufsz > LINEBUF_MAX/2)
73 uci_parse_error(ctx, "line too long");
76 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
81 * parse a character escaped by '\'
82 * returns true if the escaped character is to be parsed
83 * returns false if the escaped character is to be ignored
85 static bool parse_backslash(struct uci_context *ctx)
87 struct uci_parse_context *pctx = ctx->pctx;
92 /* undecoded backslash at the end of line, fetch the next line */
93 if (!pctx_cur_char(pctx) ||
94 pctx_cur_char(pctx) == '\n' ||
95 (pctx_cur_char(pctx) == '\r' &&
96 pctx_char(pctx, pctx_pos(pctx) + 1) == '\n' &&
97 !pctx_char(pctx, pctx_pos(pctx) + 2))) {
98 uci_getln(ctx, pctx->pos);
102 /* FIXME: decode escaped char, necessary? */
107 * move the string pointer forward until a non-whitespace character or
110 static void skip_whitespace(struct uci_context *ctx)
112 struct uci_parse_context *pctx = ctx->pctx;
114 while (pctx_cur_char(pctx) && isspace(pctx_cur_char(pctx)))
118 static inline void addc(struct uci_context *ctx, int *pos_dest, int *pos_src)
120 struct uci_parse_context *pctx = ctx->pctx;
122 pctx_char(pctx, *pos_dest) = pctx_char(pctx, *pos_src);
128 * parse a double quoted string argument from the command line
130 static void parse_double_quote(struct uci_context *ctx, int *target)
132 struct uci_parse_context *pctx = ctx->pctx;
135 /* skip quote character */
139 c = pctx_cur_char(pctx);
145 /* Multi-line str value */
146 uci_getln(ctx, pctx->pos);
147 if (!pctx_cur_char(pctx)) {
148 uci_parse_error(ctx, "EOF with unterminated \"");
152 if (!parse_backslash(ctx))
156 addc(ctx, target, &pctx->pos);
163 * parse a single quoted string argument from the command line
165 static void parse_single_quote(struct uci_context *ctx, int *target)
167 struct uci_parse_context *pctx = ctx->pctx;
169 /* skip quote character */
173 c = pctx_cur_char(pctx);
179 /* Multi-line str value */
180 uci_getln(ctx, pctx->pos);
181 if (!pctx_cur_char(pctx))
182 uci_parse_error(ctx, "EOF with unterminated '");
186 addc(ctx, target, &pctx->pos);
192 * parse a string from the command line and detect the quoting style
194 static void parse_str(struct uci_context *ctx, int *target)
196 struct uci_parse_context *pctx = ctx->pctx;
199 switch(pctx_cur_char(pctx)) {
201 parse_single_quote(ctx, target);
204 parse_double_quote(ctx, target);
207 pctx_cur_char(pctx) = 0;
215 if (!parse_backslash(ctx))
219 addc(ctx, target, &pctx->pos);
222 } while (pctx_cur_char(pctx) && !isspace(pctx_cur_char(pctx)));
226 * if the string was unquoted and we've stopped at a whitespace
227 * character, skip to the next one, because the whitespace will
228 * be overwritten by a null byte here
230 if (pctx_cur_char(pctx) && next)
233 /* terminate the parsed string */
234 pctx_char(pctx, *target) = 0;
238 * extract the next argument from the command line
240 static int next_arg(struct uci_context *ctx, bool required, bool name, bool package)
242 struct uci_parse_context *pctx = ctx->pctx;
245 skip_whitespace(ctx);
246 val = ptr = pctx_pos(pctx);
247 if (pctx_cur_char(pctx) == ';') {
248 pctx_cur_char(pctx) = 0;
251 parse_str(ctx, &ptr);
253 if (!pctx_char(pctx, val)) {
255 uci_parse_error(ctx, "insufficient arguments");
259 if (name && !uci_validate_str(pctx_str(pctx, val), name, package))
260 uci_parse_error(ctx, "invalid character in name field");
266 int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result)
271 UCI_ASSERT(ctx, str != NULL);
272 UCI_ASSERT(ctx, result != NULL);
274 if (ctx->pctx && (ctx->pctx->file != stream))
278 uci_alloc_parse_context(ctx);
280 ctx->pctx->file = stream;
284 /*FIXME do we need to skip empty lines? */
285 ofs_result = next_arg(ctx, false, false, false);
286 *result = pctx_str(ctx->pctx, ofs_result);
287 *str = pctx_cur_str(ctx->pctx);
293 uci_fill_ptr(struct uci_context *ctx, struct uci_ptr *ptr, struct uci_element *e)
295 UCI_ASSERT(ctx, ptr != NULL);
296 UCI_ASSERT(ctx, e != NULL);
298 memset(ptr, 0, sizeof(struct uci_ptr));
300 case UCI_TYPE_OPTION:
301 ptr->o = uci_to_option(e);
303 case UCI_TYPE_SECTION:
304 ptr->s = uci_to_section(e);
306 case UCI_TYPE_PACKAGE:
307 ptr->p = uci_to_package(e);
310 UCI_THROW(ctx, UCI_ERR_INVAL);
314 ptr->option = ptr->o->e.name;
315 ptr->s = ptr->o->section;
317 ptr->section = ptr->s->e.name;
318 ptr->p = ptr->s->package;
320 ptr->package = ptr->p->e.name;
322 ptr->flags |= UCI_LOOKUP_DONE;
330 * verify that the end of the line or command is reached.
331 * throw an error if extra arguments are given on the command line
333 static void assert_eol(struct uci_context *ctx)
338 skip_whitespace(ctx);
339 ofs_tmp = next_arg(ctx, false, false, false);
340 tmp = pctx_str(ctx->pctx, ofs_tmp);
341 if (*tmp && (ctx->flags & UCI_FLAG_STRICT))
342 uci_parse_error(ctx, "too many arguments");
346 * switch to a different config, either triggered by uci_load, or by a
347 * 'package <...>' statement in the import file
349 static void uci_switch_config(struct uci_context *ctx)
351 struct uci_parse_context *pctx;
352 struct uci_element *e;
358 /* add the last config to main config file list */
360 pctx->package->backend = ctx->backend;
361 uci_list_add(&ctx->root, &pctx->package->e.list);
363 pctx->package = NULL;
364 pctx->section = NULL;
371 * if an older config under the same name exists, unload it
372 * ignore errors here, e.g. if the config was not found
374 e = uci_lookup_list(&ctx->root, name);
376 UCI_THROW(ctx, UCI_ERR_DUPLICATE);
377 pctx->package = uci_alloc_package(ctx, name);
381 * parse the 'package' uci command (next config package)
383 static void uci_parse_package(struct uci_context *ctx, bool single)
385 struct uci_parse_context *pctx = ctx->pctx;
389 /* command string null-terminated by strtok */
390 pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
392 ofs_name = next_arg(ctx, true, true, true);
393 name = pctx_str(pctx, ofs_name);
398 ctx->pctx->name = name;
399 uci_switch_config(ctx);
403 * parse the 'config' uci command (open a section)
405 static void uci_parse_config(struct uci_context *ctx)
407 struct uci_parse_context *pctx = ctx->pctx;
408 struct uci_element *e;
410 int ofs_name, ofs_type;
414 uci_fixup_section(ctx, ctx->pctx->section);
415 if (!ctx->pctx->package) {
416 if (!ctx->pctx->name)
417 uci_parse_error(ctx, "attempting to import a file without a package name");
419 uci_switch_config(ctx);
422 /* command string null-terminated by strtok */
423 pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
425 ofs_type = next_arg(ctx, true, false, false);
426 type = pctx_str(pctx, ofs_type);
427 if (!uci_validate_type(type))
428 uci_parse_error(ctx, "invalid character in type field");
430 ofs_name = next_arg(ctx, false, true, false);
431 type = pctx_str(pctx, ofs_type);
432 name = pctx_str(pctx, ofs_name);
435 if (!name || !name[0]) {
436 ctx->internal = !pctx->merge;
437 UCI_NESTED(uci_add_section, ctx, pctx->package, type, &pctx->section);
439 uci_fill_ptr(ctx, &ptr, &pctx->package->e);
440 e = uci_lookup_list(&pctx->package->sections, name);
442 ptr.s = uci_to_section(e);
446 ctx->internal = !pctx->merge;
447 UCI_NESTED(uci_set, ctx, &ptr);
448 pctx->section = uci_to_section(ptr.last);
453 * parse the 'option' uci command (open a value)
455 static void uci_parse_option(struct uci_context *ctx, bool list)
457 struct uci_parse_context *pctx = ctx->pctx;
458 struct uci_element *e;
460 int ofs_name, ofs_value;
465 uci_parse_error(ctx, "option/list command found before the first section");
467 /* command string null-terminated by strtok */
468 pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
470 ofs_name = next_arg(ctx, true, true, false);
471 ofs_value = next_arg(ctx, false, false, false);
472 name = pctx_str(pctx, ofs_name);
473 value = pctx_str(pctx, ofs_value);
476 uci_fill_ptr(ctx, &ptr, &pctx->section->e);
477 e = uci_lookup_list(&pctx->section->options, name);
479 ptr.o = uci_to_option(e);
483 ctx->internal = !pctx->merge;
485 UCI_NESTED(uci_add_list, ctx, &ptr);
487 UCI_NESTED(uci_set, ctx, &ptr);
491 * parse a complete input line, split up combined commands by ';'
493 static void uci_parse_line(struct uci_context *ctx, bool single)
495 struct uci_parse_context *pctx = ctx->pctx;
498 /* Skip whitespace characters at the start of line */
499 skip_whitespace(ctx);
501 word = strtok(pctx_cur_str(pctx), " \t");
510 if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
511 uci_parse_package(ctx, single);
516 if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
517 uci_parse_config(ctx);
522 if ((word[1] == 0) || !strcmp(word + 1, "ption"))
523 uci_parse_option(ctx, false);
528 if ((word[1] == 0) || !strcmp(word + 1, "ist"))
529 uci_parse_option(ctx, true);
538 uci_parse_error(ctx, "invalid command");
542 /* max number of characters that escaping adds to the string */
543 #define UCI_QUOTE_ESCAPE "'\\''"
546 * escape an uci string for export
548 static const char *uci_escape(struct uci_context *ctx, const char *str)
554 ctx->bufsz = LINEBUF;
555 ctx->buf = malloc(LINEBUF);
564 end = strchr(str, '\'');
566 end = str + strlen(str);
569 /* make sure that we have enough room in the buffer */
570 while (ofs + len + sizeof(UCI_QUOTE_ESCAPE) + 1 > ctx->bufsz) {
572 ctx->buf = uci_realloc(ctx, ctx->buf, ctx->bufsz);
575 /* copy the string until the character before the quote */
576 memcpy(&ctx->buf[ofs], str, len);
579 /* end of string? return the buffer */
583 memcpy(&ctx->buf[ofs], UCI_QUOTE_ESCAPE, sizeof(UCI_QUOTE_ESCAPE));
584 ofs += strlen(&ctx->buf[ofs]);
593 * export a single config package to a file stream
595 static void uci_export_package(struct uci_package *p, FILE *stream, bool header)
597 struct uci_context *ctx = p->ctx;
598 struct uci_element *s, *o, *i;
601 fprintf(stream, "package %s\n", uci_escape(ctx, p->e.name));
602 uci_foreach_element(&p->sections, s) {
603 struct uci_section *sec = uci_to_section(s);
604 fprintf(stream, "\nconfig %s", uci_escape(ctx, sec->type));
605 if (!sec->anonymous || (ctx->flags & UCI_FLAG_EXPORT_NAME))
606 fprintf(stream, " '%s'", uci_escape(ctx, sec->e.name));
607 fprintf(stream, "\n");
608 uci_foreach_element(&sec->options, o) {
609 struct uci_option *opt = uci_to_option(o);
611 case UCI_TYPE_STRING:
612 fprintf(stream, "\toption %s", uci_escape(ctx, opt->e.name));
613 fprintf(stream, " '%s'\n", uci_escape(ctx, opt->v.string));
616 uci_foreach_element(&opt->v.list, i) {
617 fprintf(stream, "\tlist %s", uci_escape(ctx, opt->e.name));
618 fprintf(stream, " '%s'\n", uci_escape(ctx, i->name));
622 fprintf(stream, "\t# unknown type for option '%s'\n", uci_escape(ctx, opt->e.name));
627 fprintf(stream, "\n");
630 int uci_export(struct uci_context *ctx, FILE *stream, struct uci_package *package, bool header)
632 struct uci_element *e;
635 UCI_ASSERT(ctx, stream != NULL);
638 uci_export_package(package, stream, header);
640 uci_foreach_element(&ctx->root, e) {
641 uci_export_package(uci_to_package(e), stream, header);
648 int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct uci_package **package, bool single)
650 struct uci_parse_context *pctx;
653 /* make sure no memory from previous parse attempts is leaked */
656 uci_alloc_parse_context(ctx);
659 if (package && *package && single) {
660 pctx->package = *package;
665 * If 'name' was supplied, assume that the supplied stream does not contain
666 * the appropriate 'package <name>' string to specify the config name
667 * NB: the config file can still override the package name
670 UCI_ASSERT(ctx, uci_validate_package(name));
674 while (!feof(pctx->file)) {
677 UCI_TRAP_SAVE(ctx, error);
679 uci_parse_line(ctx, single);
680 UCI_TRAP_RESTORE(ctx);
683 if (ctx->flags & UCI_FLAG_PERROR)
684 uci_perror(ctx, NULL);
685 if ((ctx->err != UCI_ERR_PARSE) ||
686 (ctx->flags & UCI_FLAG_STRICT))
687 UCI_THROW(ctx, ctx->err);
690 uci_fixup_section(ctx, ctx->pctx->section);
691 if (!pctx->package && name)
692 uci_switch_config(ctx);
694 *package = pctx->package;
696 pctx->package = NULL;
699 uci_switch_config(ctx);
701 /* no error happened, we can get rid of the parser context now */
708 static char *uci_config_path(struct uci_context *ctx, const char *name)
712 UCI_ASSERT(ctx, uci_validate_package(name));
713 filename = uci_malloc(ctx, strlen(name) + strlen(ctx->confdir) + 2);
714 sprintf(filename, "%s/%s", ctx->confdir, name);
719 static void uci_file_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
721 struct uci_package *p = *package;
722 FILE *f1, *f2 = NULL;
725 char *filename = NULL;
727 bool do_rename = false;
731 p->path = uci_config_path(ctx, p->e.name);
733 UCI_THROW(ctx, UCI_ERR_INVAL);
736 if ((asprintf(&filename, "%s/.%s.uci-XXXXXX", ctx->confdir, p->e.name) < 0) || !filename)
737 UCI_THROW(ctx, UCI_ERR_MEM);
739 if (!mktemp(filename))
744 UCI_THROW(ctx, UCI_ERR_IO);
747 if ((stat(filename, &statbuf) == 0) && ((statbuf.st_mode & S_IFMT) != S_IFREG))
748 UCI_THROW(ctx, UCI_ERR_IO);
750 /* open the config file for writing now, so that it is locked */
751 f1 = uci_open_stream(ctx, p->path, NULL, SEEK_SET, true, true);
753 /* flush unsaved changes and reload from delta file */
754 UCI_TRAP_SAVE(ctx, done);
757 name = uci_strdup(ctx, p->e.name);
758 path = uci_strdup(ctx, p->path);
759 /* dump our own changes to the delta file */
760 if (!uci_list_empty(&p->delta))
761 UCI_INTERNAL(uci_save, ctx, p);
764 * other processes might have modified the config
765 * as well. dump and reload
767 uci_free_package(&p);
769 UCI_INTERNAL(uci_import, ctx, f1, name, &p, true);
775 /* freed together with the uci_package */
780 if (!uci_load_delta(ctx, p, true))
784 f2 = uci_open_stream(ctx, filename, p->path, SEEK_SET, true, true);
785 uci_export(ctx, f2, p, false);
789 uci_close_stream(f2);
793 UCI_TRAP_RESTORE(ctx);
798 uci_close_stream(f1);
799 if (do_rename && rename(filename, p->path)) {
801 UCI_THROW(ctx, UCI_ERR_IO);
806 UCI_THROW(ctx, ctx->err);
811 * This function returns the filename by returning the string
812 * after the last '/' character. By checking for a non-'\0'
813 * character afterwards, directories are ignored (glob marks
814 * those with a trailing '/'
816 static inline char *get_filename(char *path)
820 p = strrchr(path, '/');
827 static char **uci_list_config_files(struct uci_context *ctx)
835 dir = uci_malloc(ctx, strlen(ctx->confdir) + 1 + sizeof("/*"));
836 sprintf(dir, "%s/*", ctx->confdir);
837 if (glob(dir, GLOB_MARK, NULL, &globbuf) != 0) {
839 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
842 size = sizeof(char *) * (globbuf.gl_pathc + 1);
843 for(i = 0; i < globbuf.gl_pathc; i++) {
846 p = get_filename(globbuf.gl_pathv[i]);
850 size += strlen(p) + 1;
853 configs = uci_malloc(ctx, size);
854 buf = (char *) &configs[globbuf.gl_pathc + 1];
855 for(i = 0; i < globbuf.gl_pathc; i++) {
858 p = get_filename(globbuf.gl_pathv[i]);
862 if (!uci_validate_package(p))
867 buf += strlen(buf) + 1;
874 static struct uci_package *uci_file_load(struct uci_context *ctx, const char *name)
876 struct uci_package *package = NULL;
883 /* relative path outside of /etc/config */
885 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
888 /* absolute path outside of /etc/config */
889 filename = uci_strdup(ctx, name);
890 name = strrchr(name, '/') + 1;
894 /* config in /etc/config */
895 filename = uci_config_path(ctx, name);
900 UCI_TRAP_SAVE(ctx, done);
901 file = uci_open_stream(ctx, filename, NULL, SEEK_SET, false, false);
903 UCI_INTERNAL(uci_import, ctx, file, name, &package, true);
904 UCI_TRAP_RESTORE(ctx);
907 package->path = filename;
908 package->has_delta = confdir;
909 uci_load_delta(ctx, package, false);
913 uci_close_stream(file);
916 UCI_THROW(ctx, ctx->err);
921 __private UCI_BACKEND(uci_file_backend, "file",
922 .load = uci_file_load,
923 .commit = uci_file_commit,
924 .list_configs = uci_list_config_files,