Fix UBSAN failure in RangeTest.cpp with libstdc++-v4.9

[folly.git] / folly / String.h

diff --git a/folly/String.h b/folly/String.h
index 53b54f42f8c7f022643941431341fc5bd2c98842..750863b986bbe52b4812aaa0ed8f84cc89052779 100644 (file)
--- a/folly/String.h
+++ b/folly/String.h
@@ -211,12 +211,15 @@ std::string& stringVAppendf(std::string* out, const char* format, va_list ap);
  * C++, use cEscape instead.  This function is for display purposes
  * only.
  */
-template <class String1, class String2>
-void backslashify(const String1& input, String2& output, bool hex_style=false);
+template <class OutputString>
+void backslashify(
+    folly::StringPiece input,
+    OutputString& output,
+    bool hex_style = false);
 
-template <class String>
-String backslashify(const String& input, bool hex_style=false) {
-  String output;
+template <class OutputString = std::string>
+OutputString backslashify(StringPiece input, bool hex_style = false) {
+  OutputString output;
   backslashify(input, output, hex_style);
   return output;
 }
@@ -465,21 +468,6 @@ void splitTo(const Delim& delimiter,
  * Note that this will likely not work if the last field's target is of numeric
  * type, in which case folly::to<> will throw an exception.
  */
-template <class T, class Enable = void>
-struct IsSomeVector {
-  enum { value = false };
-};
-
-template <class T>
-struct IsSomeVector<std::vector<T>, void> {
-  enum { value = true };
-};
-
-template <class T>
-struct IsSomeVector<fbvector<T>, void> {
-  enum { value = true };
-};
-
 template <class T, class Enable = void>
 struct IsConvertible {
   enum { value = false };
@@ -618,7 +606,7 @@ std::string stripLeftMargin(std::string s);
  * Leaves all other characters unchanged, including those with the 0x80
  * bit set.
  * @param str String to convert
- * @param len Length of str, in bytes
+ * @param length Length of str, in bytes
  */
 void toLowerAscii(char* str, size_t length);
 
@@ -626,6 +614,11 @@ inline void toLowerAscii(MutableStringPiece str) {
   toLowerAscii(str.begin(), str.size());
 }
 
+inline void toLowerAscii(std::string& str) {
+  // str[0] is legal also if the string is empty.
+  toLowerAscii(&str[0], str.size());
+}
+
 template <
     class Iterator = const char*,
     class Base = folly::Range<boost::u8_to_u32_iterator<Iterator>>>