text: /*
    This awesome collection of macros was taken from http://c.learncodethehardway.org/book/ex20.html
  */
  
  #ifndef __dbg_h__
  #define __dbg_h__
  
  #define NDEBUG
  #include <stdio.h>
  #include <errno.h>
  #include <string.h>
  
  #ifdef NDEBUG
  #define debug(M, ...)
  #else
  #define debug(M, ...) fprintf(stderr, "DEBUG %s:%d: " M "\n", __FILE__, __LINE__, ##__VA_ARGS__)
  #endif
  
  #define clean_errno() (errno == 0 ? "None" : strerror(errno))
  
  #define log_err(M, ...) fprintf(stderr, "[ERROR] (%s:%d: errno: %s) " M "\n", __FILE__, __LINE__, clean_errno(), ##__VA_ARGS__)
  
  #define log_warn(M, ...) fprintf(stderr, "[WARN] (%s:%d: errno: %s) " M "\n", __FILE__, __LINE__, clean_errno(), ##__VA_ARGS__)
  
  #define log_info(M, ...) fprintf(stderr, "[INFO] (%s:%d) " M "\n", __FILE__, __LINE__, ##__VA_ARGS__)
  
  #define check(A, M, ...) if(!(A)) { log_err(M, ##__VA_ARGS__); errno=0; goto error; }
  
  #define sentinel(M, ...)  { log_err(M, ##__VA_ARGS__); errno=0; goto error; }
  
  #define check_mem(A) check((A), "Out of memory.")
  
  #define check_debug(A, M, ...) if(!(A)) { debug(M, ##__VA_ARGS__); errno=0; goto error; }
  
  #endif
  