+/*
+ * 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, char **str, char **result)
+{
+ UCI_HANDLE_ERR(ctx);
+ UCI_ASSERT(ctx, (str != NULL) && (*str != NULL));
+ UCI_ASSERT(ctx, result != NULL);
+
+ *result = next_arg(ctx, str, false, false);
+ return 0;
+}
+
+