Is there a better way to do C style error handling?

Question

I\'m trying to learn C by writing a simple parser / compiler. So far its been a very enlightening experience, however coming from a strong background in C# I\'m having some pro

Answer 1

One technique for cleanup is to use an while loop that will never actually iterate. It gives you goto without using goto.

#define NOT_ERROR(x) if ((x) < 0) break;
#define NOT_NULL(x) if ((x) == NULL) break;

// Initialise things that may need to be cleaned up here.
char* somePtr = NULL;

do
{
    NOT_NULL(somePtr = malloc(1024));
    NOT_ERROR(something(somePtr));
    NOT_ERROR(somethingElse(somePtr));
    // etc

    // if you get here everything's ok.
    return somePtr;
}
while (0);

// Something went wrong so clean-up.
free(somePtr);
return NULL;

You lose a level of indentation though.

Edit: I'd like to add that I've nothing against goto, it's just that for the use-case of the questioner he doesn't really need it. There are cases where using goto beats the pants off any other method, but this isn't one of them.