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 misc utility functions and wrappers to standard
17 * functions, which throw exceptions upon failure.
19 #include <sys/types.h>
28 #define LINEBUF_MAX 4096
30 __plugin
void *uci_malloc(struct uci_context
*ctx
, size_t size
)
36 UCI_THROW(ctx
, UCI_ERR_MEM
);
42 __plugin
void *uci_realloc(struct uci_context
*ctx
, void *ptr
, size_t size
)
44 ptr
= realloc(ptr
, size
);
46 UCI_THROW(ctx
, UCI_ERR_MEM
);
51 __plugin
char *uci_strdup(struct uci_context
*ctx
, const char *str
)
57 UCI_THROW(ctx
, UCI_ERR_MEM
);
62 /* Based on an efficient hash function published by D. J. Bernstein */
63 static unsigned int djbhash(unsigned int hash
, char *str
)
65 int len
= strlen(str
);
72 for(i
= 0; i
< len
; i
++) {
73 hash
= ((hash
<< 5) + hash
) + str
[i
];
75 return (hash
& 0x7FFFFFFF);
79 * validate strings for names and types, reject special characters
80 * for names, only alphanum and _ is allowed (shell compatibility)
81 * for types, we allow more characters
83 __plugin
bool uci_validate_str(const char *str
, bool name
)
90 if (!isalnum(c
) && c
!= '_') {
91 if (name
|| (c
< 33) || (c
> 126))
99 static inline bool uci_validate_name(const char *str
)
101 return uci_validate_str(str
, true);
104 bool uci_validate_text(const char *str
)
107 if ((*str
== '\r') || (*str
== '\n') ||
108 ((*str
< 32) && (*str
!= '\t')))
115 static void uci_alloc_parse_context(struct uci_context
*ctx
)
117 ctx
->pctx
= (struct uci_parse_context
*) uci_malloc(ctx
, sizeof(struct uci_parse_context
));
120 int uci_parse_ptr(struct uci_context
*ctx
, struct uci_ptr
*ptr
, char *str
)
126 UCI_ASSERT(ctx
, str
);
127 UCI_ASSERT(ctx
, ptr
);
129 memset(ptr
, 0, sizeof(struct uci_ptr
));
132 last
= strchr(str
, '=');
139 ptr
->package
= strsep(&str
, ".");
143 ptr
->section
= strsep(&str
, ".");
145 ptr
->target
= UCI_TYPE_PACKAGE
;
149 ptr
->option
= strsep(&str
, ".");
151 ptr
->target
= UCI_TYPE_SECTION
;
154 ptr
->target
= UCI_TYPE_OPTION
;
157 tmp
= strsep(&str
, ".");
162 if (ptr
->package
&& !uci_validate_str(ptr
->package
, false))
164 if (ptr
->section
&& !uci_validate_name(ptr
->section
))
165 ptr
->flags
|= UCI_LOOKUP_EXTENDED
;
166 if (ptr
->option
&& !uci_validate_name(ptr
->option
))
168 if (ptr
->value
&& !uci_validate_text(ptr
->value
))
174 memset(ptr
, 0, sizeof(struct uci_ptr
));
175 UCI_THROW(ctx
, UCI_ERR_PARSE
);
179 static void uci_parse_error(struct uci_context
*ctx
, char *pos
, char *reason
)
181 struct uci_parse_context
*pctx
= ctx
->pctx
;
183 pctx
->reason
= reason
;
184 pctx
->byte
= pos
- pctx
->buf
;
185 UCI_THROW(ctx
, UCI_ERR_PARSE
);
190 * Fetch a new line from the input stream and resize buffer if necessary
192 static void uci_getln(struct uci_context
*ctx
, int offset
)
194 struct uci_parse_context
*pctx
= ctx
->pctx
;
198 if (pctx
->buf
== NULL
) {
199 pctx
->buf
= uci_malloc(ctx
, LINEBUF
);
200 pctx
->bufsz
= LINEBUF
;
208 p
= fgets(p
, pctx
->bufsz
- ofs
, pctx
->file
);
213 if (pctx
->buf
[ofs
- 1] == '\n') {
215 pctx
->buf
[ofs
- 1] = 0;
219 if (pctx
->bufsz
> LINEBUF_MAX
/2)
220 uci_parse_error(ctx
, p
, "line too long");
223 pctx
->buf
= uci_realloc(ctx
, pctx
->buf
, pctx
->bufsz
);
228 * parse a character escaped by '\'
229 * returns true if the escaped character is to be parsed
230 * returns false if the escaped character is to be ignored
232 static inline bool parse_backslash(struct uci_context
*ctx
, char **str
)
237 /* undecoded backslash at the end of line, fetch the next line */
240 uci_getln(ctx
, *str
- ctx
->pctx
->buf
);
244 /* FIXME: decode escaped char, necessary? */
249 * move the string pointer forward until a non-whitespace character or
252 static void skip_whitespace(struct uci_context
*ctx
, char **str
)
255 while (**str
&& isspace(**str
))
259 if (!parse_backslash(ctx
, str
))
264 static inline void addc(char **dest
, char **src
)
272 * parse a double quoted string argument from the command line
274 static void parse_double_quote(struct uci_context
*ctx
, char **str
, char **target
)
278 /* skip quote character */
281 while ((c
= **str
)) {
288 if (!parse_backslash(ctx
, str
))
296 uci_parse_error(ctx
, *str
, "unterminated \"");
300 * parse a single quoted string argument from the command line
302 static void parse_single_quote(struct uci_context
*ctx
, char **str
, char **target
)
305 /* skip quote character */
308 while ((c
= **str
)) {
318 uci_parse_error(ctx
, *str
, "unterminated '");
322 * parse a string from the command line and detect the quoting style
324 static void parse_str(struct uci_context
*ctx
, char **str
, char **target
)
330 parse_single_quote(ctx
, str
, target
);
333 parse_double_quote(ctx
, str
, target
);
344 if (!parse_backslash(ctx
, str
))
351 } while (**str
&& !isspace(**str
));
355 * if the string was unquoted and we've stopped at a whitespace
356 * character, skip to the next one, because the whitespace will
357 * be overwritten by a null byte here
362 /* terminate the parsed string */
367 * extract the next argument from the command line
369 static char *next_arg(struct uci_context
*ctx
, char **str
, bool required
, bool name
)
375 skip_whitespace(ctx
, str
);
380 parse_str(ctx
, str
, &ptr
);
384 uci_parse_error(ctx
, *str
, "insufficient arguments");
388 if (name
&& !uci_validate_name(val
))
389 uci_parse_error(ctx
, val
, "invalid character in field");
395 int uci_parse_argument(struct uci_context
*ctx
, FILE *stream
, char **str
, char **result
)
398 UCI_ASSERT(ctx
, str
!= NULL
);
399 UCI_ASSERT(ctx
, result
!= NULL
);
402 if (ctx
->pctx
->file
!= stream
) {
406 uci_alloc_parse_context(ctx
);
407 ctx
->pctx
->file
= stream
;
411 *str
= ctx
->pctx
->buf
;
414 *result
= next_arg(ctx
, str
, false, false);
421 * open a stream and go to the right position
423 * note: when opening for write and seeking to the beginning of
424 * the stream, truncate the file
426 static FILE *uci_open_stream(struct uci_context
*ctx
, const char *filename
, int pos
, bool write
, bool create
)
431 int mode
= (write
? O_RDWR
: O_RDONLY
);
436 if (!write
&& ((stat(filename
, &statbuf
) < 0) ||
437 ((statbuf
.st_mode
& S_IFMT
) != S_IFREG
))) {
438 UCI_THROW(ctx
, UCI_ERR_NOTFOUND
);
441 fd
= open(filename
, mode
, UCI_FILEMODE
);
445 if (flock(fd
, (write
? LOCK_EX
: LOCK_SH
)) < 0)
448 ret
= lseek(fd
, 0, pos
);
453 file
= fdopen(fd
, (write
? "w+" : "r"));
458 UCI_THROW(ctx
, UCI_ERR_IO
);
463 static void uci_close_stream(FILE *stream
)