BLI_string_utils: add BLI_string_join_array_by_sep_char

Utility to join strings into a fixed size buffer.

source/blender/blenlib/intern/string_utils.c

@@ -434,6 +434,29 @@ char *BLI_string_join_array(char *result,
   return c;
 }
 
+/**
+ * A version of #BLI_string_join that takes a separator which can be any character including '\0'.
+ */
+char *BLI_string_join_array_by_sep_char(
+    char *result, size_t result_len, char sep, const char *strings[], uint strings_len)
+{
+  char *c = result;
+  char *c_end = &result[result_len - 1];
+  for (uint i = 0; i < strings_len; i++) {
+    if (i != 0) {
+      if (c < c_end) {
+        *c++ = sep;
+      }
+    }
+    const char *p = strings[i];
+    while (*p && (c < c_end)) {
+      *c++ = *p++;
+    }
+  }
+  *c = '\0';
+  return c;
+}
+
 /**
  * Join an array of strings into a newly allocated, null terminated string.
  */