About

The repo contains header files that can be included into a C source file to enable several different debugging macros. There is a header file for both C89 debug89.h and C99+ debug.h. Both of these header files include the same macros, but require slightly different usage.

Macros

There are five different macros defined in the header:

• debug() is used for general purpose debugging statements.
• debug_w() is used for warning messages.
• debug_e() is used for error messages.
• debug_wtf() is used for things that should never ever happen. (What a Terrible Failure!)
• assert() is used to check the truth of some boolean expression.

All of the debug statements support printf-style format strings (excluding assert()). Additionally, a newline is automatically written after each message, so you don't need to add \n to the end of your debug statements.

By default, these macros produce no output. Output must be explicitly enabled by including the -DDEBUG flag during compilation.

gcc -DDEBUG foobar.c -o foobar

Usage: C89 / ANSI C

Include the debug89.h header in your code. Due to the lack of __VA_ARGS__ in C89, the macro calls must be wrapped in two sets of parentheses to cope with a variable number of parameters. The exception to this rule is the assert() macro, which only uses a single set of parentheses.

/* Two sets of parentheses. */
debug(("A debug message!"));
debug_w(("Parameter x has a negative value: %d", x));

/* Single set of parentheses. */
assert(x != 3);

See demo89.c for example usage.

Usage: C99 or Later

Include the debug.h header in your code. Use all of the macros with a single set of parentheses.

/* Single set of parentheses. */
debug("A debug message!");
debug_w("Parameter x has negative value: %d", x);

/* Single set of parentheses. */
assert(x != 3);

See demo.c for example usage.

ANSI Colors

ANSI color escape sequences can be enabled to make the output of the debugging statements more visible. Simply add the -DDEBUG_COLOR flag to your compilation command along with -DDEBUG. This option will only work correctly if your terminal supports ANSI escape sequences (i.e. not cmd.exe on Windows).

Example Output

Here's an example of colorized output from the demo program.

(Un)license

This project is released into the public domain under the terms of The Unlicense.