CommonFuncs: Add StrerrorString version of LastStrerrorString that accepts an error number.

Source/Core/Common/CommonFuncs.cpp

@@ -43,13 +43,18 @@ const char* StrErrorWrapper(int error, char* buffer, std::size_t length)
 #endif
 }
 
+std::string StrerrorString(int error)
+{
+  char error_message[BUFFER_SIZE];
+
+  return StrErrorWrapper(error, error_message, BUFFER_SIZE);
+}
+
 // Wrapper function to get last strerror(errno) string.
 // This function might change the error code.
 std::string LastStrerrorString()
 {
-  char error_message[BUFFER_SIZE];
-
-  return StrErrorWrapper(errno, error_message, BUFFER_SIZE);
+  return StrerrorString(errno);
 }
 
 #ifdef _WIN32

Source/Core/Common/CommonFuncs.h

@@ -45,8 +45,9 @@ namespace Common
 // strerror_r wrapper to handle XSI and GNU versions.
 const char* StrErrorWrapper(int error, char* buffer, std::size_t length);
 
-// Wrapper function to get last strerror(errno) string.
-// This function might change the error code.
+// Wrapper functions to get strerror(errno) string, which itself is not threadsafe.
+// These functions might change the error code.
+std::string StrerrorString(int error);
 std::string LastStrerrorString();
 
 #ifdef _WIN32