+static char *pprint_rename(const char *a, const char *b)
+{
+ const char *old = a;
+ const char *new = b;
+ char *name = NULL;
+ int pfx_length, sfx_length;
+ int len_a = strlen(a);
+ int len_b = strlen(b);
+
+ /* Find common prefix */
+ pfx_length = 0;
+ while (*old && *new && *old == *new) {
+ if (*old == '/')
+ pfx_length = old - a + 1;
+ old++;
+ new++;
+ }
+
+ /* Find common suffix */
+ old = a + len_a;
+ new = b + len_b;
+ sfx_length = 0;
+ while (a <= old && b <= new && *old == *new) {
+ if (*old == '/')
+ sfx_length = len_a - (old - a);
+ old--;
+ new--;
+ }
+
+ /*
+ * pfx{mid-a => mid-b}sfx
+ * {pfx-a => pfx-b}sfx
+ * pfx{sfx-a => sfx-b}
+ * name-a => name-b
+ */
+ if (pfx_length + sfx_length) {
+ name = xmalloc(len_a + len_b - pfx_length - sfx_length + 7);
+ sprintf(name, "%.*s{%.*s => %.*s}%s",
+ pfx_length, a,
+ len_a - pfx_length - sfx_length, a + pfx_length,
+ len_b - pfx_length - sfx_length, b + pfx_length,
+ a + len_a - sfx_length);
+ }
+ else {
+ name = xmalloc(len_a + len_b + 5);
+ sprintf(name, "%s => %s", a, b);
+ }
+ return name;
+}
+