fixed mod property names and added unit test for xm

tests/utils.h

@@ -9,7 +9,9 @@
 #include <sys/fcntl.h>
 #endif
 #include <stdio.h>
+#include <string.h>
 #include <string>
+#include <fstream>
 
 using namespace std;
 
@@ -45,6 +47,35 @@ inline void deleteFile(const string &filename)
   remove(filename.c_str());
 }
 
+inline bool fileEqual(const string &filename1, const string &filename2)
+{
+  char buf1[BUFSIZ];
+  char buf2[BUFSIZ];
+
+  ifstream stream1(filename1.c_str(), ios_base::in | ios_base::binary);
+  ifstream stream2(filename2.c_str(), ios_base::in | ios_base::binary);
+
+  if(!stream1 && !stream2) return true;
+  if(!stream1 || !stream2) return false;
+
+  for(;;)
+  {
+    stream1.read(buf1, BUFSIZ);
+    stream2.read(buf2, BUFSIZ);
+
+    streamsize n1 = stream1.gcount();
+    streamsize n2 = stream2.gcount();
+
+    if(n1 != n2) return false;
+
+    if(n1 == 0) break;
+
+    if(memcmp(buf1, buf2, n1) != 0) return false;
+  }
+
+  return stream1.good() == stream2.good();
+}
+
 class ScopedFileCopy
 {
 public: