/fpm/zlog.c

	/* $Id: zlog.c,v 1.7 2008/05/22 21:08:32 anight Exp $ */
	/* (c) 2004-2007 Andrei Nigmatulin */

#include "fpm_config.h"

#include <stdio.h>
#include <unistd.h>
#include <time.h>
#include <string.h>
#include <stdarg.h>
#include <sys/time.h>
#include <errno.h>

#include "zlog.h"

#define MAX_LINE_LENGTH 1024

static int zlog_fd = -1;
static int zlog_level = ZLOG_NOTICE;

static const char *level_names[] = {
	[ZLOG_DEBUG]		= "DEBUG",
	[ZLOG_NOTICE]		= "NOTICE",
	[ZLOG_WARNING]		= "WARNING",
	[ZLOG_ERROR]		= "ERROR",
	[ZLOG_ALERT]		= "ALERT",
};

size_t zlog_print_time(struct timeval *tv, char *timebuf, size_t timebuf_len)
{
	struct tm t;
	size_t len;

	len = strftime(timebuf, timebuf_len, "%b %d %H:%M:%S", localtime_r((const time_t *) &tv->tv_sec, &t));
	len += snprintf(timebuf + len, timebuf_len - len, ".%06d", (int) tv->tv_usec);

	return len;
}

int zlog_set_fd(int new_fd)
{
	int old_fd = zlog_fd;
	zlog_fd = new_fd;

	return old_fd;
}

int zlog_set_level(int new_value)
{
	int old_value = zlog_level;

	zlog_level = new_value;

	return old_value;
}

void zlog(const char *function, int line, int flags, const char *fmt, ...)
{
	struct timeval tv;
	char buf[MAX_LINE_LENGTH];
	const size_t buf_size = MAX_LINE_LENGTH;
	va_list args;
	size_t len;
	int truncated = 0;
	int saved_errno;

	if ((flags & ZLOG_LEVEL_MASK) < zlog_level) {
		return;
	}

	saved_errno = errno;

	gettimeofday(&tv, 0);

	len = zlog_print_time(&tv, buf, buf_size);

	len += snprintf(buf + len, buf_size - len, " [%s] %s(), line %d: ", level_names[flags & ZLOG_LEVEL_MASK], function, line);

	if (len > buf_size - 1) {
		truncated = 1;
	}

	if (!truncated) {
		va_start(args, fmt);

		len += vsnprintf(buf + len, buf_size - len, fmt, args);

		va_end(args);

		if (len >= buf_size) {
			truncated = 1;
		}
	}

	if (!truncated) {
		if (flags & ZLOG_HAVE_ERRNO) {
			len += snprintf(buf + len, buf_size - len, ": %s (%d)", strerror(saved_errno), saved_errno);
			if (len >= buf_size) {
				truncated = 1;
			}
		}
	}

	if (truncated) {
		memcpy(buf + buf_size - sizeof("..."), "...", sizeof("...") - 1);
		len = buf_size - 1;
	}

	buf[len++] = '\n';

	write(zlog_fd > -1 ? zlog_fd : STDERR_FILENO, buf, len);
}