update stringutils.cpp

core/components/stringutils.cpp

@@ -116,8 +116,26 @@ string StringUtils::bytet2Binary(uint32_t value, int bitCount, bool remoteZero)
     }
   }
   if (remoteZero) {
-    while (ret[0] == '0') {
-      ret = ret.substr(1);
+    while (ret.length() > 0 && ret[0] == '0') {
+      ret = ret.substr(1, ret.length() - 1);
+    }
+  }
+  return ret;
+}
+string StringUtils::bytet2BinaryBigEnd(uint32_t value, int bitCount, bool remoteZero) {
+  string ret;
+  for (int i = 0; i < bitCount; ++i) {
+    uint32_t bit = value & 0x01;
+    value        = value >> 1;
+    if (bit == 0) {
+      ret = ret + "0";
+    } else {
+      ret = ret + "1";
+    }
+  }
+  if (remoteZero) {
+    while (ret.length() > 0 && ret[ret.length() - 1] == '0') {
+      ret = ret.substr(0, ret.length() - 1);
     }
   }
   return ret;

core/components/stringutils.hpp

@@ -62,6 +62,7 @@ class StringUtils {
    *
    */
   string bytet2Binary(uint32_t value, int bitCount, bool remoteZero = true);
+  string bytet2BinaryBigEnd(uint32_t value, int bitCount, bool remoteZero = true);
 };
 
 }  // namespace core