X-Git-Url: http://git.archive.openwrt.org/?p=project%2Fuci.git;a=blobdiff_plain;f=util.c;h=f0b2094810bcd8c75cb6097b62a76dbaabbc45da;hp=e76ff6be35699e6202bc9f58334a090b0c36608b;hb=ec7b1de53e16991b071c892fac149b4bfe73c539;hpb=818f7b8433ae369c20fc56cccbb55b22043b9024

diff --git a/util.c b/util.c
index e76ff6b..f0b2094 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 <sys/types.h>
 #include <sys/stat.h>
@@ -23,11 +23,12 @@
 #include <unistd.h>
 #include <ctype.h>
 #include <fcntl.h>
+#include <errno.h>
 
 #define LINEBUF	32
 #define LINEBUF_MAX	4096
 
-static void *uci_malloc(struct uci_context *ctx, size_t size)
+__plugin void *uci_malloc(struct uci_context *ctx, size_t size)
 {
 	void *ptr;
 
@@ -39,7 +40,7 @@ static void *uci_malloc(struct uci_context *ctx, size_t size)
 	return ptr;
 }
 
-static void *uci_realloc(struct uci_context *ctx, void *ptr, size_t size)
+__plugin void *uci_realloc(struct uci_context *ctx, void *ptr, size_t size)
 {
 	ptr = realloc(ptr, size);
 	if (!ptr)
@@ -48,7 +49,7 @@ static void *uci_realloc(struct uci_context *ctx, void *ptr, size_t size)
 	return ptr;
 }
 
-static char *uci_strdup(struct uci_context *ctx, const char *str)
+__plugin char *uci_strdup(struct uci_context *ctx, const char *str)
 {
 	char *ptr;
 
@@ -59,67 +60,131 @@ static char *uci_strdup(struct uci_context *ctx, const char *str)
 	return ptr;
 }
 
-static bool uci_validate_name(const char *str)
+/* 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)
+ * for types, we allow more characters
+ */
+__plugin bool uci_validate_str(const char *str, bool name)
 {
 	if (!*str)
 		return false;
 
 	while (*str) {
-		if (!isalnum(*str) && (*str != '_'))
+		unsigned char c = *str;
+		if (!isalnum(c) && c != '_') {
+			if (name || (c < 33) || (c > 126))
+				return false;
+		}
+		str++;
+	}
+	return true;
+}
+
+static inline bool uci_validate_package(const char *str)
+{
+	return uci_validate_str(str, false);
+}
+
+static inline bool uci_validate_type(const char *str)
+{
+	return uci_validate_str(str, false);
+}
+
+static inline bool uci_validate_name(const char *str)
+{
+	return uci_validate_str(str, true);
+}
+
+bool uci_validate_text(const char *str)
+{
+	while (*str) {
+		unsigned char c = *str;
+		if ((c == '\r') || (c == '\n') ||
+			((c < 32) && (c != '\t')))
 			return false;
 		str++;
 	}
 	return true;
 }
 
-int uci_parse_tuple(struct uci_context *ctx, char *str, char **package, char **section, char **option, char **value)
+static void uci_alloc_parse_context(struct uci_context *ctx)
+{
+	ctx->pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
+}
+
+int uci_parse_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str)
 {
 	char *last = NULL;
+	char *tmp;
 
 	UCI_HANDLE_ERR(ctx);
-	UCI_ASSERT(ctx, str && package && section && option);
+	UCI_ASSERT(ctx, str);
+	UCI_ASSERT(ctx, ptr);
 
-	*package = strtok(str, ".");
-	if (!*package || !uci_validate_name(*package))
+	memset(ptr, 0, sizeof(struct uci_ptr));
+
+	/* value */
+	last = strchr(str, '=');
+	if (last) {
+		*last = 0;
+		last++;
+		ptr->value = last;
+	}
+
+	ptr->package = strsep(&str, ".");
+	if (!ptr->package)
 		goto error;
 
-	last = *package;
-	*section = strtok(NULL, ".");
-	if (!*section)
+	ptr->section = strsep(&str, ".");
+	if (!ptr->section) {
+		ptr->target = UCI_TYPE_PACKAGE;
 		goto lastval;
+	}
 
-	last = *section;
-	*option = strtok(NULL, ".");
-	if (!*option)
+	ptr->option = strsep(&str, ".");
+	if (!ptr->option) {
+		ptr->target = UCI_TYPE_SECTION;
 		goto lastval;
+	} else {
+		ptr->target = UCI_TYPE_OPTION;
+	}
 
-	last = *option;
+	tmp = strsep(&str, ".");
+	if (tmp)
+		goto error;
 
 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 (ptr->package && !uci_validate_package(ptr->package))
 		goto error;
-	if (*option && !uci_validate_name(*option))
+	if (ptr->section && !uci_validate_name(ptr->section))
+		ptr->flags |= UCI_LOOKUP_EXTENDED;
+	if (ptr->option && !uci_validate_name(ptr->option))
+		goto error;
+	if (ptr->value && !uci_validate_text(ptr->value))
 		goto error;
 
-	goto done;
+	return 0;
 
 error:
+	memset(ptr, 0, sizeof(struct uci_ptr));
 	UCI_THROW(ctx, UCI_ERR_PARSE);
-
-done:
-	return 0;
 }
 
 
@@ -171,6 +236,199 @@ 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)
+{
+	bool next = true;
+	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 ';':
+			next = false;
+			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 && next)
+		*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);
+	if(*str[0] == ';') {
+		*str[0] = 0;
+		*str += 1;
+	} else {
+		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 && (ctx->pctx->file != stream))
+		uci_cleanup(ctx);
+
+	if (!ctx->pctx)
+		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
  *
@@ -193,10 +451,11 @@ 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)
+	ret = flock(fd, (write ? LOCK_EX : LOCK_SH));
+	if ((ret < 0) && (errno != ENOSYS))
 		goto error;
 
 	ret = lseek(fd, 0, pos);
@@ -221,6 +480,7 @@ static void uci_close_stream(FILE *stream)
 	if (!stream)
 		return;
 
+	fflush(stream);
 	fd = fileno(stream);
 	flock(fd, LOCK_UN);
 	fclose(stream);