Debugging an audio driver

The Audio DDK uses several constants to turn debugging messages on and off. The main one is ADO_DEBUG.

The standard Audio DDK makefiles define ADO_DEBUG if you've defined DEBUG in your environment. If you compile your driver with debugging options, ADO_DEBUG is defined as well to help you debug your logic.

If ADO_DEBUG is defined, several things happen:

• Error messages and warnings generated by your calls to ado_error() and ado_debug() are printed on standard output as well as being sent to the system logger, slogger. In nondebug mode, they're sent only to slogger. For more information about the system logger, see the QNX Utilities Reference.
• Full memory accounting is provided for all the ado_* memory functions:
  • ado_calloc(),
  • ado_free(),
  • ado_malloc(),
  • ado_realloc(),
  • ado_strdup()

  You can call ado_memory_dump() to get a full listing of active memory. In nondebug mode, these memory functions are defined to be the standard C library functions.

If you've set ADO_DEBUG, you can also define the following macros to get specialized debug output:

• ADO_MUTEX_DEBUG — used by ado_mutex_destroy(), ado_mutex_init(), ado_mutex_lock(), and ado_mutex_unlock().
• ADO_RWLOCK_DEBUG — used by ado_rwlock_destroy(), ado_rwlock_init(), ado_rwlock_rdlock(), ado_rwlock_unlock(), and ado_rwlock_wrlock().

If you define these macros, you'll see a message whenever a lock is changed. You'll probably need to define them only if you encounter a locking problem.