repos_ecs/其他2015后/日志库/log4c-1.2.4/examples/example_appenders.c

/******************************************************************************
 * 
 * Part of the log4c examples.
 *
 * Along with example_formatters.c this file is used to create a small
 * library of custom appenders and formatters.
 *
 * This library is excercised using application_2 and a sample log4crc 
 * config file.
 *
 *****************************************************************************/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYSLOG_H
#include <syslog.h>
#endif
#include <time.h>

#include <log4c.h>

/* global var to force linking with the appender when using syslog */
static int log4c_to_syslog_priority(int a_priority);

/*
 * This one is experimental and not in use.  But its a good example to see all the things
 * you have access to during the call to the appender
 */

static int s13_file_append(log4c_appender_t* this, 
			   const log4c_logging_event_t* a_event)
{
    FILE* fp = log4c_appender_get_udata(this);

    /*
      return fprintf(fp, "[%s] [%s] [%d] [%d] [%s] [%s] [%d]\n%s", 
      log4c_appender_get_name(this),
      a_event->evt_category,
      a_event->evt_priority,
      a_event->evt_timestamp.tv_sec*1000000 + a_event->evt_timestamp.tv_usec,
      a_event->evt_msg, 
      a_event->evt_loc->loc_file,
      a_event->evt_loc->loc_line,
      a_event->evt_rendered_msg);
    */

    return fprintf(fp, "%s\n", 
		   a_event->evt_rendered_msg   
	);
}

/*******************************************************************************/
static int etf_open(log4c_appender_t* this)
{
    FILE* fp = log4c_appender_get_udata(this);
    
    if (fp)
	return 0;
    
    if ( (fp = fopen(log4c_appender_get_name(this), "a+")) == NULL)
	fp = stderr;
    
    /* unbuffered mode */
    setbuf(fp, NULL);
    
    log4c_appender_set_udata(this, fp);
    return 0;
}


/*******************************************************************************/
static int etf_close(log4c_appender_t* this)
{
    FILE* fp = log4c_appender_get_udata(this);
    
    return (fp ? fclose(fp) : 0);
}

const log4c_appender_type_t log4c_appender_type_s13_file = {
    "s13_file",
    etf_open,
    s13_file_append,
    etf_close,
};

/*******************************************************************************/
/*
 * The log4c stderr adds a "[stderr] " in front of the message
 * it is logging.  this one doesn't, and  leaves the formatting
 * descisions up to the formatter
 */
static int s13_stderr_append(log4c_appender_t* this, 
			     const log4c_logging_event_t* a_event)
{
    return fprintf(stderr, "%s\n", 
		   a_event->evt_rendered_msg   
	);
}
static int s13_stderr_open(log4c_appender_t* this)
{
    /* fprintf (stderr,"running s13_stderr appender open command now\n"); */
    return 0;
}

const log4c_appender_type_t log4c_appender_type_s13_stderr = {
   "s13_stderr",
   s13_stderr_open,
   s13_stderr_append,
   NULL,
};


#ifdef HAVE_SYSLOG_H
/**************************/
/*    User appender    */
/**************************/
/*******************************************************************************/
static int syslog_user_open(log4c_appender_t* this)
{
    openlog(log4c_appender_get_name(this), LOG_PID, LOG_USER);
    return 0;
}

/*******************************************************************************/
static int syslog_user_append(log4c_appender_t*	this, 
			      const log4c_logging_event_t* a_event)
{

    syslog(log4c_to_syslog_priority(a_event->evt_priority) | LOG_USER,
	   "%s", a_event->evt_rendered_msg); 
    return 0;
}

/*******************************************************************************/
static int syslog_user_close(log4c_appender_t*	this)
{
    closelog();
    return 0;
}

/*******************************************************************************/

const log4c_appender_type_t log4c_appender_type_syslog_user = {
    "syslog_user",
    syslog_user_open,
    syslog_user_append,
    syslog_user_close,
};

/**************************/
/*    Local 0 appender    */
/**************************/
/*******************************************************************************/
static int syslog_local0_open(log4c_appender_t* this)
{
    openlog(log4c_appender_get_name(this), LOG_PID, LOG_LOCAL0);
    return 0;
}

/*******************************************************************************/
static int syslog_local0_append(log4c_appender_t*	this, 
				const log4c_logging_event_t* a_event)
{

    syslog(log4c_to_syslog_priority(a_event->evt_priority) | LOG_LOCAL0,
	   "%s", a_event->evt_rendered_msg);
    return 0;
}

/*******************************************************************************/
static int syslog_local0_close(log4c_appender_t*	this)
{
    closelog();
    return 0;
}

/*******************************************************************************/

const log4c_appender_type_t log4c_appender_type_syslog_local0 = {
  "syslog_local0",
  syslog_local0_open,
  syslog_local0_append,
  syslog_local0_close,
};


static int log4c_to_syslog_priority(int a_priority)
{
    static int priorities[] = {
        LOG_EMERG,
        LOG_ALERT,
        LOG_CRIT,
        LOG_ERR,
        LOG_WARNING,
        LOG_NOTICE,
        LOG_INFO,
        LOG_DEBUG
    };
    int result;

    a_priority++;
    a_priority /= 100;

    if (a_priority < 0) {
        result = LOG_EMERG;
    } else if (a_priority > 7) {
        result = LOG_DEBUG;
    } else {
        result = priorities[a_priority];
    }

    return result;
}


#endif /* HAVE_SYSLOG_H */

/*****************************************************/

static const log4c_appender_type_t * const appender_types[] = {
#ifdef HAVE_SYSLOG_H
    &log4c_appender_type_syslog_local0,
    &log4c_appender_type_syslog_user,
#endif    
  &log4c_appender_type_s13_file,
  &log4c_appender_type_s13_stderr
};
int nappender_types = 
  (int)(sizeof(appender_types) / sizeof(appender_types[0]));

int init_example_appenders(){

  int rc = 0; int i = 0;

  for (i = 0; i < nappender_types; i++) 
    log4c_appender_type_set(appender_types[i]);
    
  return(rc);			
}