sane-project-backends/include/sane/sanei_debug.h

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3.8 KiB
C

/** @file sanei_debug.h
* Support for printing debug messages.
*
* Use the functions of this header file to print debug or warning messages.
*/
#ifndef _SANEI_DEBUG_H
#define _SANEI_DEBUG_H
#include <sane/sanei.h>
#ifdef __cplusplus
extern "C" {
#endif
/** @name Public macros
* These macros can be used in backends and other SANE-related
* code.
*
* Before including sanei_debug.h, the following macros must be set:
*
* - BACKEND_NAME - The name of your backend without double-quotes (must be set in any case)
* - STUBS - If this is defined, no macros will be included. Used in
* backends consisting of more than one .c file.
* - DEBUG_DECLARE_ONLY - Generates prototypes instead of functions. Used in
* backends consisting of more than one .c file.
* - DEBUG_NOT_STATIC - Doesn't generate static functions. Used in header files if
* they are include in more than one .c file.
*
* @{
*/
/** @def DBG_INIT()
* Initialize sanei_debug.
*
* Call this function before you use any DBG function.
*/
/** @def DBG(level, fmt, ...)
* Print a message at debug level `level' or higher using a printf-like
* function. Example: DBG(1, "sane_open: opening fd \%d\\n", fd).
*
* @param level debug level
* @param fmt format (see man 3 printf for details)
* @param ... additional arguments
*/
/** @def IF_DBG(x)
* Compile code only if debugging is enabled.
*
* Expands to x if debug support is enabled at compile-time. If NDEBUG is
* defined at compile-time this macro expands to nothing.
*
* @param x code to expand when debugging is enabled
*/
/**
* @def DBG_LEVEL
* Current debug level.
*
* You can only read this "variable".
*/
/** @def ENTRY(name)
* Expands to sane_BACKEND_NAME_name.
*
* Example: ENTRY(init) in mustek.c will expand to sane_mustek_init.
*/
/* @} */
/** @hideinitializer*/
#define ENTRY(name) PASTE(PASTE(PASTE(sane_,BACKEND_NAME),_),name)
#ifdef NDEBUG
extern void sanei_debug_ndebug (int level, const char *msg, ...);
# define DBG_LEVEL (0)
# define DBG_INIT()
# define DBG sanei_debug_ndebug
# define IF_DBG(x)
#else /* !NDEBUG */
/** @hideinitializer*/
# define DBG_LEVEL PASTE(sanei_debug_,BACKEND_NAME)
# if defined(BACKEND_NAME) && !defined(STUBS)
# ifdef DEBUG_DECLARE_ONLY
extern int DBG_LEVEL;
# else /* !DEBUG_DECLARE_ONLY */
int DBG_LEVEL = 0;
# endif /* DEBUG_DECLARE_ONLY */
# endif /* BACKEND_NAME && !STUBS */
/** @hideinitializer*/
# define DBG_INIT() \
sanei_init_debug (STRINGIFY(BACKEND_NAME), &DBG_LEVEL)
/** @hideinitializer*/
# define DBG_LOCAL PASTE(DBG_LEVEL,_call)
# ifndef STUBS
# ifdef DEBUG_DECLARE_ONLY
extern void DBG_LOCAL (int level, const char *msg, ...)
#ifdef __GNUC__
__attribute__ ((format (printf, 2, 3)))
#endif
;
# else /* !DEBUG_DECLARE_ONLY */
# include <stdarg.h>
extern void sanei_debug_msg
(int level, int max_level, const char *be, const char *fmt, va_list ap);
#ifdef __GNUC__
# ifndef DEBUG_NOT_STATIC
static
# endif /* !DEBUG_NOT_STATIC */
void DBG_LOCAL (int level, const char *msg, ...) __attribute__ ((format (printf, 2, 3)));
#endif /* __GNUC__ */
# ifndef DEBUG_NOT_STATIC
static
# endif /* !DEBUG_NOT_STATIC */
void
DBG_LOCAL (int level, const char *msg, ...)
{
va_list ap;
va_start (ap, msg);
sanei_debug_msg (level, DBG_LEVEL, STRINGIFY(BACKEND_NAME), msg, ap);
va_end (ap);
}
# endif /* DEBUG_DECLARE_ONLY */
# endif /* !STUBS */
/** @hideinitializer*/
# define DBG DBG_LOCAL
extern void sanei_init_debug (const char * backend, int * debug_level_var);
/** @hideinitializer*/
# define IF_DBG(x) x
#endif /* NDEBUG */
#ifdef __cplusplus
} // extern "C"
#endif
#endif /* _SANEI_DEBUG_H */