receive-pack: detect aliased updates which can occur with symrefs

diff --git a/strbuf.c b/strbuf.c
index 67448b7b07aa9d07b0c8cc250e3e0fad64c8fb5e..bc3a0802ea7e7b1743602972de182391b4bf0b3f 100644 (file)
--- a/strbuf.c
+++ b/strbuf.c
@@ -10,6 +10,15 @@ int prefixcmp(const char *str, const char *prefix)
                        return (unsigned char)*prefix - (unsigned char)*str;
 }
 
+int suffixcmp(const char *str, const char *suffix)
+{
+       int len = strlen(str), suflen = strlen(suffix);
+       if (len < suflen)
+               return -1;
+       else
+               return strcmp(str + len - suflen, suffix);
+}
+
 /*
  * Used as the default ->buf value, so that people can always assume
  * buf is non NULL and ->buf is NUL terminated even for a freshly