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 wrappers to standard functions, which
17 * throw exceptions upon failure.
19 #include <sys/types.h>
28 #define LINEBUF_MAX 4096
30 static void *uci_malloc(struct uci_context *ctx, size_t size)
36 UCI_THROW(ctx, UCI_ERR_MEM);
42 static 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 static char *uci_strdup(struct uci_context *ctx, const char *str)
57 UCI_THROW(ctx, UCI_ERR_MEM);
63 * validate strings for names and types, reject special characters
64 * for names, only alphanum and _ is allowed (shell compatibility)
65 * for types, we allow more characters
67 static bool uci_validate_str(const char *str, bool name)
74 if (!isalnum(c) && c != '_') {
75 if (name || (c < 33) || (c > 126))
83 static inline bool uci_validate_name(const char *str)
85 return uci_validate_str(str, true);
88 static void uci_alloc_parse_context(struct uci_context *ctx)
90 ctx->pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
93 int uci_parse_tuple(struct uci_context *ctx, char *str, char **package, char **section, char **option, char **value)
98 UCI_ASSERT(ctx, str && package && section && option);
100 *package = strtok(str, ".");
101 if (!*package || !uci_validate_name(*package))
105 *section = strtok(NULL, ".");
110 *option = strtok(NULL, ".");
117 last = strchr(last, '=');
129 if (*section && !uci_validate_name(*section))
131 if (*option && !uci_validate_name(*option))
137 UCI_THROW(ctx, UCI_ERR_PARSE);
144 static void uci_parse_error(struct uci_context *ctx, char *pos, char *reason)
146 struct uci_parse_context *pctx = ctx->pctx;
148 pctx->reason = reason;
149 pctx->byte = pos - pctx->buf;
150 UCI_THROW(ctx, UCI_ERR_PARSE);
155 * Fetch a new line from the input stream and resize buffer if necessary
157 static void uci_getln(struct uci_context *ctx, int offset)
159 struct uci_parse_context *pctx = ctx->pctx;
163 if (pctx->buf == NULL) {
164 pctx->buf = uci_malloc(ctx, LINEBUF);
165 pctx->bufsz = LINEBUF;
173 p = fgets(p, pctx->bufsz - ofs, pctx->file);
178 if (pctx->buf[ofs - 1] == '\n') {
180 pctx->buf[ofs - 1] = 0;
184 if (pctx->bufsz > LINEBUF_MAX/2)
185 uci_parse_error(ctx, p, "line too long");
188 pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
193 * parse a character escaped by '\'
194 * returns true if the escaped character is to be parsed
195 * returns false if the escaped character is to be ignored
197 static inline bool parse_backslash(struct uci_context *ctx, char **str)
202 /* undecoded backslash at the end of line, fetch the next line */
205 uci_getln(ctx, *str - ctx->pctx->buf);
209 /* FIXME: decode escaped char, necessary? */
214 * move the string pointer forward until a non-whitespace character or
217 static void skip_whitespace(struct uci_context *ctx, char **str)
220 while (**str && isspace(**str))
224 if (!parse_backslash(ctx, str))
229 static inline void addc(char **dest, char **src)
237 * parse a double quoted string argument from the command line
239 static void parse_double_quote(struct uci_context *ctx, char **str, char **target)
243 /* skip quote character */
246 while ((c = **str)) {
253 if (!parse_backslash(ctx, str))
261 uci_parse_error(ctx, *str, "unterminated \"");
265 * parse a single quoted string argument from the command line
267 static void parse_single_quote(struct uci_context *ctx, char **str, char **target)
270 /* skip quote character */
273 while ((c = **str)) {
283 uci_parse_error(ctx, *str, "unterminated '");
287 * parse a string from the command line and detect the quoting style
289 static void parse_str(struct uci_context *ctx, char **str, char **target)
294 parse_single_quote(ctx, str, target);
297 parse_double_quote(ctx, str, target);
305 if (!parse_backslash(ctx, str))
312 } while (**str && !isspace(**str));
316 * if the string was unquoted and we've stopped at a whitespace
317 * character, skip to the next one, because the whitespace will
318 * be overwritten by a null byte here
323 /* terminate the parsed string */
328 * extract the next argument from the command line
330 static char *next_arg(struct uci_context *ctx, char **str, bool required, bool name)
336 skip_whitespace(ctx, str);
337 parse_str(ctx, str, &ptr);
340 uci_parse_error(ctx, *str, "insufficient arguments");
344 if (name && !uci_validate_name(val))
345 uci_parse_error(ctx, val, "invalid character in field");
351 int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result)
354 UCI_ASSERT(ctx, str != NULL);
355 UCI_ASSERT(ctx, result != NULL);
358 if (ctx->pctx->file != stream) {
359 ctx->internal = true;
363 uci_alloc_parse_context(ctx);
364 ctx->pctx->file = stream;
368 *str = ctx->pctx->buf;
371 *result = next_arg(ctx, str, false, false);
378 * open a stream and go to the right position
380 * note: when opening for write and seeking to the beginning of
381 * the stream, truncate the file
383 static FILE *uci_open_stream(struct uci_context *ctx, const char *filename, int pos, bool write, bool create)
388 int mode = (write ? O_RDWR : O_RDONLY);
393 if (!write && ((stat(filename, &statbuf) < 0) ||
394 ((statbuf.st_mode & S_IFMT) != S_IFREG))) {
395 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
398 fd = open(filename, mode, UCI_FILEMODE);
402 if (flock(fd, (write ? LOCK_EX : LOCK_SH)) < 0)
405 ret = lseek(fd, 0, pos);
410 file = fdopen(fd, (write ? "w+" : "r"));
415 UCI_THROW(ctx, UCI_ERR_IO);
420 static void uci_close_stream(FILE *stream)