utlist: Fix a segfault in DL_INSERT_INORDER2.

This was a cut-and-paste error in 47145f5.

Thanks to @MattiasErikssonAxentia for the patch and test-case!

src/utlist.h

@@ -838,7 +838,7 @@ do {
     (head) = (add);                                                                            \
   } else {                                                                                     \
     char *_tmp = (char*)(head);                                                                \
-    while ((char*)(head)->next != _tmp && (cmp((head)->next, add)) < 0) {                      \
+    while ((head)->next && (cmp((head)->next, add)) < 0) {                                     \
       (head) = (head)->next;                                                                   \
     }                                                                                          \
     (add)->prev = (head);                                                                      \

tests/test94.ans

@@ -1,6 +1,13 @@
-n g m f l e k d j c i b o h a 
+LL_INSERT_INORDER
+list1: n g m f l e k d j c i b o h a 
+list2: o h a i b j c k d l e m f n g 
 DL_INSERT_INORDER
-n g m f l e k d j c i b o h a 
+list1: n g m f l e k d j c i b o h a 
+list2: o h a i b j c k d l e m f n g 
 CDL_INSERT_INORDER
+list1:
 n g m f l e k d j c i b o h a 
 n a h o b i c j d k e l f m g 
+list2:
+o h a i b j c k d l e m f n g 
+o g n f m e l d k c j b i a h 

tests/test94.c

@@ -3,52 +3,91 @@
 
 typedef struct el {
     int id, score;
-    struct el *next2, *prev2;
+    struct el *next, *prev;
+    struct el *next_list2, *prev_list2;
 } el;
 
 static int order_desc(el *a, el *b)
 {
     return (a->score > b->score) ? -1 : (a->score < b->score);
 }
 
+static int order_asc(el *a, el *b)
+{
+    return -order_desc(a, b);
+}
+
 int main(int argc, char *argv[])
 {
     int i;
     el *head = NULL;
+    el *head2 = NULL;
     el els[15], *e;
 
     for (i=0; i<15; i++) {
         els[i].id = (int)'a'+i;
         els[i].score = i%7;
-        LL_INSERT_INORDER2(head, &els[i], order_desc, next2);
+        LL_INSERT_INORDER(head, &els[i], order_desc);
+        LL_INSERT_INORDER2(head2, &els[i], order_asc, next_list2);
+    }
+
+    printf("LL_INSERT_INORDER\n");
+    printf("list1: ");
+    LL_FOREACH(head, e) {
+        printf("%c ", e->id);
     }
-    LL_FOREACH2(head, e, next2) {
+    printf("\n");
+    printf("list2: ");
+    LL_FOREACH2(head2, e, next_list2) {
         printf("%c ", e->id);
     }
     printf("\n");
 
     printf("DL_INSERT_INORDER\n");
     head = NULL;
+    head2 = NULL;
     for (i=0; i<15; i++) {
-        DL_INSERT_INORDER2(head, &els[i], order_desc, prev2, next2);
+        DL_INSERT_INORDER(head, &els[i], order_desc);
+        DL_INSERT_INORDER2(head2, &els[i], order_asc, prev_list2, next_list2);
     }
-    DL_FOREACH2(head, e, next2) {
+
+    printf("list1: ");
+    DL_FOREACH(head, e) {
+        printf("%c ", e->id);
+    }
+    printf("\n");
+    printf("list2: ");
+    DL_FOREACH2(head2, e, next_list2) {
         printf("%c ", e->id);
     }
     printf("\n");
 
     printf("CDL_INSERT_INORDER\n");
     head = NULL;
+    head2 = NULL;
     for (i=0; i<15; i++) {
-        CDL_INSERT_INORDER2(head, &els[i], order_desc, prev2, next2);
+        CDL_INSERT_INORDER(head, &els[i], order_desc);
+        CDL_INSERT_INORDER2(head2, &els[i], order_asc, prev_list2, next_list2);
     }
-    CDL_FOREACH2(head, e, next2) {
+    printf("list1:\n");
+    CDL_FOREACH(head, e) {
         printf("%c ", e->id);
     }
     printf("\n");
-    CDL_FOREACH2(head, e, prev2) {
+    CDL_FOREACH2(head, e, prev) {
+        printf("%c ", e->id);
+    }
+    printf("\n");
+
+    printf("list2:\n");
+    CDL_FOREACH2(head2, e, next_list2) {
         printf("%c ", e->id);
     }
     printf("\n");
+    CDL_FOREACH2(head2, e, prev_list2) {
+        printf("%c ", e->id);
+    }
+    printf("\n");
+
     return 0;
 }