lib: fix infinite loop on empty regexp matches in uc_split()

The regular expression `/()/` will match the empty string, causing the
match loop to never advance. Add extra logic to deal with this case,
similar to the empty separator string logic.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

1 files changed, 12 insertions, 2 deletions

diff --git a/lib.c b/lib.c
index e204ded..6235470 100644
--- a/lib.c
+++ b/lib.c
@@ -927,9 +927,18 @@ uc_split(uc_vm_t *vm, size_t nargs)
 			if (res == REG_NOMATCH)
 				break;
 
-			ucv_array_push(arr, ucv_string_new_length(splitstr, pmatch.rm_so));
+			if (pmatch.rm_so != pmatch.rm_eo) {
+				ucv_array_push(arr, ucv_string_new_length(splitstr, pmatch.rm_so));
+				splitstr += pmatch.rm_eo;
+			}
+			else if (*splitstr) {
+				ucv_array_push(arr, ucv_string_new_length(splitstr, 1));
+				splitstr++;
+			}
+			else {
+				goto out;
+			}
 
-			splitstr += pmatch.rm_eo;
 			eflags |= REG_NOTBOL;
 		}
 
@@ -956,6 +965,7 @@ uc_split(uc_vm_t *vm, size_t nargs)
 		return NULL;
 	}
 
+out:
 	return arr;
 }