Question

I am using the macros __FILE__ and __func__ for retrieving the file and function location.
My code is structured like this… (note i am using a game engine )

Test.h

class TestClass
{
...
void Log(int status);
...
};

Test.cpp

...
void TestClass::Log(int status)
{
printf("%s %s %i",__FILE__,__func__, status);
}
...

.

and i create a class object and use it to log whatever i want to.

example.cpp

#include "Test.h"
    ...
TestClass tt;
    ...
    tt.Log((int)1);
    ...

the problem is that the output pastes the file and function name of the Test.cpp, and note the filename and function of example.cpp.

Is there a way around this or do i have to directly use the printf statement again and again?

Thanks

Answer 1

You don’t need to use printf wherever in the code, but you will need to call TestClass::Log with extra parameters __FILE__ and __func__.

Don’t threat however, you can create a macro for that so you don’t have to write down the extra parameters on each call:

#define TEST_CLASS_LOG(testClassInstance,status) \
              testClassInstance.Log((int)status, __FILE__, __func__);

and instead of calling

tt.Log((int)1);

you would call

TEST_CLASS_LOG(tt,1);

You’d need to change the Log signature to account for the extra parameters of course:

void Log(int status, const char* fileName, const char* functionName);

Also, I see Log isn’t accessing any class members, so you can make it even easier and make it static:

class TestClass
{
   static void Log(int status);
};

void TestClass::Log(int status, const char* file, const char* func)
{
   printf("%s %s %i", file, func, status);
}

#define TEST_CLASS_LOG(status) \
                  TestClass::Log((int)status, __FILE__, __func__);

So, if you do it like this, you’d only need to call:

TEST_CLASS_LOG(1);

Unfortunately there’s no way to do this automatically, without modifying your code, as macros expand at runtime. What your compiler sees now is:

void TestClass::Log(int status)
{
   printf("%s %s %i","Test.cpp","Log", status);
}

that is why you need the file name and function name passed as parameters.