+static int slow_same_name(const char *name1, int len1, const char *name2, int len2)
+{
+ if (len1 != len2)
+ return 0;
+
+ while (len1) {
+ unsigned char c1 = *name1++;
+ unsigned char c2 = *name2++;
+ len1--;
+ if (c1 != c2) {
+ c1 = toupper(c1);
+ c2 = toupper(c2);
+ if (c1 != c2)
+ return 0;
+ }
+ }
+ return 1;
+}
+
+static int same_name(const struct cache_entry *ce, const char *name, int namelen, int icase)
+{
+ int len = ce_namelen(ce);
+
+ /*
+ * Always do exact compare, even if we want a case-ignoring comparison;
+ * we do the quick exact one first, because it will be the common case.
+ */
+ if (len == namelen && !cache_name_compare(name, namelen, ce->name, len))
+ return 1;
+
+ return icase && slow_same_name(name, namelen, ce->name, len);
+}
+
+struct cache_entry *index_name_exists(struct index_state *istate, const char *name, int namelen, int icase)