X-Git-Url: http://git.archive.openwrt.org/?p=project%2Fuci.git;a=blobdiff_plain;f=util.c;h=35aa2b6e8a66dca190a55ab21383824cbefd4b50;hp=78b22cffae25849ebed5715b4f243d602374ffed;hb=4f629ff865b978a7ea399776ff6af83c6428bda0;hpb=e828bcf07c0602746dffcc9927c446d1fe4c3ad9 diff --git a/util.c b/util.c index 78b22cf..35aa2b6 100644 --- a/util.c +++ b/util.c @@ -13,8 +13,8 @@ */ /* - * This file contains wrappers to standard functions, which - * throw exceptions upon failure. + * This file contains misc utility functions and wrappers to standard + * functions, which throw exceptions upon failure. */ #include #include @@ -59,6 +59,22 @@ static char *uci_strdup(struct uci_context *ctx, const char *str) return ptr; } +/* Based on an efficient hash function published by D. J. Bernstein */ +static unsigned int djbhash(unsigned int hash, char *str) +{ + int len = strlen(str); + int i; + + /* initial value */ + if (hash == ~0) + hash = 5381; + + for(i = 0; i < len; i++) { + hash = ((hash << 5) + hash) + str[i]; + } + return (hash & 0x7FFFFFFF); +} + /* * validate strings for names and types, reject special characters * for names, only alphanum and _ is allowed (shell compatibility) @@ -97,36 +113,35 @@ int uci_parse_tuple(struct uci_context *ctx, char *str, char **package, char **s UCI_HANDLE_ERR(ctx); UCI_ASSERT(ctx, str && package && section && option); - *package = strtok(str, "."); + last = strchr(str, '='); + if (last) { + *last = 0; + last++; + } + + *package = strsep(&str, "."); if (!*package || !uci_validate_name(*package)) goto error; - last = *package; - *section = strtok(NULL, "."); + *section = strsep(&str, "."); if (!*section) goto lastval; - last = *section; - *option = strtok(NULL, "."); + *option = strsep(&str, "."); if (!*option) goto lastval; - last = *option; - lastval: - last = strchr(last, '='); if (last) { if (!value) goto error; - *last = 0; - last++; if (!*last) goto error; *value = last; } - if (*section && !uci_validate_name(*section)) + if (*section && *section[0] && !uci_validate_name(*section)) goto error; if (*option && !uci_validate_name(*option)) goto error; @@ -189,6 +204,190 @@ static void uci_getln(struct uci_context *ctx, int offset) } while (1); } +/* + * parse a character escaped by '\' + * returns true if the escaped character is to be parsed + * returns false if the escaped character is to be ignored + */ +static inline bool parse_backslash(struct uci_context *ctx, char **str) +{ + /* skip backslash */ + *str += 1; + + /* undecoded backslash at the end of line, fetch the next line */ + if (!**str) { + *str += 1; + uci_getln(ctx, *str - ctx->pctx->buf); + return false; + } + + /* FIXME: decode escaped char, necessary? */ + return true; +} + +/* + * move the string pointer forward until a non-whitespace character or + * EOL is reached + */ +static void skip_whitespace(struct uci_context *ctx, char **str) +{ +restart: + while (**str && isspace(**str)) + *str += 1; + + if (**str == '\\') { + if (!parse_backslash(ctx, str)) + goto restart; + } +} + +static inline void addc(char **dest, char **src) +{ + **dest = **src; + *dest += 1; + *src += 1; +} + +/* + * parse a double quoted string argument from the command line + */ +static void parse_double_quote(struct uci_context *ctx, char **str, char **target) +{ + char c; + + /* skip quote character */ + *str += 1; + + while ((c = **str)) { + switch(c) { + case '"': + **target = 0; + *str += 1; + return; + case '\\': + if (!parse_backslash(ctx, str)) + continue; + /* fall through */ + default: + addc(target, str); + break; + } + } + uci_parse_error(ctx, *str, "unterminated \""); +} + +/* + * parse a single quoted string argument from the command line + */ +static void parse_single_quote(struct uci_context *ctx, char **str, char **target) +{ + char c; + /* skip quote character */ + *str += 1; + + while ((c = **str)) { + switch(c) { + case '\'': + **target = 0; + *str += 1; + return; + default: + addc(target, str); + } + } + uci_parse_error(ctx, *str, "unterminated '"); +} + +/* + * parse a string from the command line and detect the quoting style + */ +static void parse_str(struct uci_context *ctx, char **str, char **target) +{ + do { + switch(**str) { + case '\'': + parse_single_quote(ctx, str, target); + break; + case '"': + parse_double_quote(ctx, str, target); + break; + case '#': + **str = 0; + /* fall through */ + case 0: + goto done; + case '\\': + if (!parse_backslash(ctx, str)) + continue; + /* fall through */ + default: + addc(target, str); + break; + } + } while (**str && !isspace(**str)); +done: + + /* + * if the string was unquoted and we've stopped at a whitespace + * character, skip to the next one, because the whitespace will + * be overwritten by a null byte here + */ + if (**str) + *str += 1; + + /* terminate the parsed string */ + **target = 0; +} + +/* + * extract the next argument from the command line + */ +static char *next_arg(struct uci_context *ctx, char **str, bool required, bool name) +{ + char *val; + char *ptr; + + val = ptr = *str; + skip_whitespace(ctx, str); + parse_str(ctx, str, &ptr); + if (!*val) { + if (required) + uci_parse_error(ctx, *str, "insufficient arguments"); + goto done; + } + + if (name && !uci_validate_name(val)) + uci_parse_error(ctx, val, "invalid character in field"); + +done: + return val; +} + +int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result) +{ + UCI_HANDLE_ERR(ctx); + UCI_ASSERT(ctx, str != NULL); + UCI_ASSERT(ctx, result != NULL); + + if (ctx->pctx) { + if (ctx->pctx->file != stream) { + uci_cleanup(ctx); + } + } else { + uci_alloc_parse_context(ctx); + ctx->pctx->file = stream; + } + if (!*str) { + uci_getln(ctx, 0); + *str = ctx->pctx->buf; + } + + *result = next_arg(ctx, str, false, false); + + return 0; +} + + /* * open a stream and go to the right position * @@ -211,7 +410,7 @@ static FILE *uci_open_stream(struct uci_context *ctx, const char *filename, int } fd = open(filename, mode, UCI_FILEMODE); - if (fd <= 0) + if (fd < 0) goto error; if (flock(fd, (write ? LOCK_EX : LOCK_SH)) < 0)