misc: Add `find_delm()`, and `get_str_delm_range()`

`find_delm()` finds the first matched delimiter of the supplied
delimiter(s), and either returns the pointer to the first non-delimiter
character after the match, or the match itself if `skip_delm` is true,
or false respectivly.

`get_str_delm_range()` finds, and returns the string in between the
supplied starting, and ending delimiter(s). It also returns the pointer
to the first non-delimiter character after the end of the range in
`rhs`.

1 files changed, 33 insertions, 0 deletions

diff --git a/misc.c b/misc.c
index af40bff..8246ba1 100644
--- a/misc.c
+++ b/misc.c
@@ -69,6 +69,39 @@ char *get_line(char **str) {
 	}
 }
 
+char *find_delm(char *str, const char *delm, int skip_delm) {
+	if (!is_empty(str)) {
+		const size_t span = strcspn(str, delm);
+		return &str[(skip_delm) ? strspn(&str[span], delm) : span];
+	} else {
+		return NULL;
+	}
+}
+
+char *get_str_delm_range(char *str, const char *start_delm, const char *end_delm, char **rhs) {
+	if (!is_empty(str)) {
+		char *start = find_delm(str, start_delm, 1);
+		char *end;
+		char *dummy;
+		rhs = (rhs != NULL) ? rhs : &dummy;
+
+		for (end = start; *end != '\0'; end += strcspn(end, end_delm)) {
+			if (*end++ == '\\') {
+				end += strspn(end, end_delm);
+				continue;
+			} else {
+				break;
+			}
+		}
+
+		*end++ = '\0';
+		*rhs = end;
+		return start;
+	} else {
+		return NULL;
+	}
+}
+
 char *make_str(const char *str) {
 	const size_t length = strlen(str);
 	char *s = calloc(length+1, sizeof(char));