#define _GNU_SOURCE 1

#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>

#include "notify.h"

/*
 * Generic console notifier.
 */

static void
notify_fn_default_(int level, const char * func_name, const char * fmt, ...)
{
	FILE  *f = (level <= 1) ? stderr : stdout;
	static const char * const levels[] = { "FATAL", "ERROR", "INFO", "DEBUG" };
	const int levels_num = sizeof levels / sizeof *levels;
	va_list ap;

	flockfile(f);

	fputs_unlocked((func_name && *func_name) ? func_name : "[null]", f);
	fputs_unlocked(": --", f);
	if (level >= 0
	&&  level <= levels_num) {
		fputs_unlocked(levels[level], f);
	} else {
		fprintf(f, "%d", level);
	}
	fputs_unlocked("-- ", f);

	va_start(ap, fmt);
	vfprintf(f, fmt, ap);
	va_end(ap);

	fputc_unlocked('\n', f);
	fflush_unlocked(f);

	funlockfile(f);

}

void (* notify_fn)(int level, const char *func_name, const char *msg, ...) __attribute__((format(printf, 3, 4))) = notify_fn_default_;

void
notify_fn_set(void (* fn)(int level, const char *func_name, const char *fmt, ...))
{
	notify_fn = fn;
}