Add overloads for ConvToNum to prevent (unsigned) char weirdness.

1 files changed, 16 insertions, 0 deletions

diff --git a/include/convto.h b/include/convto.h
index 3332580ed..2f808d1fb 100644
--- a/include/convto.h
+++ b/include/convto.h
@@ -99,3 +99,19 @@ template<typename TOut> inline TOut ConvToNum(const std::string& in)
 		return 0;
 	return ret;
 }
+
+template<> inline char ConvToNum<char>(const std::string& in)
+{
+	// We specialise ConvToNum for char to avoid istringstream treating
+	// the input as a character literal.
+	uint16_t num = ConvToNum<uint16_t>(in);
+	return num <= UINT8_MAX ? num : 0;
+}
+
+template<> inline unsigned char ConvToNum<unsigned char>(const std::string& in)
+{
+	// We specialise ConvToNum for unsigned char to avoid istringstream
+	// treating the input as a character literal.
+	int16_t num = ConvToNum<int16_t>(in);
+	return num >= INT8_MIN && num <= INT8_MAX ? num : 0;
+}