logging.c

bind 9.3结合mysql数据库

		if (!log_check_channel(lc, level, chan))
			continue;

		if (!did_vsprintf) {
			if (VSPRINTF((lc->buffer, format, args)) >
			    (size_t)LOG_BUFFER_SIZE) {
				syslog(LOG_CRIT,
				       "memory overrun in log_vwrite()");
				exit(1);
			}
			did_vsprintf = 1;
		}

		switch (chan->type) {
		case log_syslog:
			if (level >= log_critical)
				pri = (level >= 0) ? 0 : -level;
			else
				pri = -log_critical;
			syslog(chan->out.facility|syslog_priority[pri],
			       "%s%s%s%s",
			       (chan->flags & LOG_TIMESTAMP) ?	time_buf : "",
			       (chan->flags & LOG_PRINT_CATEGORY) ?
			       category_name : "",
			       (chan->flags & LOG_PRINT_LEVEL) ?
			       level_str : "",
			       lc->buffer);
			break;
		case log_file:
			stream = chan->out.file.stream;
			if (stream == NULL) {
				stream = log_open_stream(chan);
				if (stream == NULL)
					break;
			}
			if (chan->out.file.max_size != ULONG_MAX) {
				long pos;
				
				pos = ftell(stream);
				if (pos >= 0 &&
				    (unsigned long)pos >
				    chan->out.file.max_size) {
					/*
					 * try to roll over the log files,
					 * ignoring all all return codes
					 * except the open (we don't want
					 * to write any more anyway)
					 */
					log_close_stream(chan);
					version_rename(chan);
					stream = log_open_stream(chan);
					if (stream == NULL)
						break;
				}
			}
			fprintf(stream, "%s%s%s%s\n", 
				(chan->flags & LOG_TIMESTAMP) ?	time_buf : "",
				(chan->flags & LOG_PRINT_CATEGORY) ?
				category_name : "",
				(chan->flags & LOG_PRINT_LEVEL) ?
				level_str : "",
				lc->buffer);
			fflush(stream);
			break;
		case log_null:
			break;
		default:
			syslog(LOG_ERR,
			       "unknown channel type in log_vwrite()");
		}
	}
}

void
log_write(log_context lc, int category, int level, const char *format, ...) {
	va_list args;

	va_start(args, format);
	log_vwrite(lc, category, level, format, args);
	va_end(args);
}

/*
 * Functions to create, set, or destroy contexts
 */

int
log_new_context(int num_categories, char **category_names, log_context *lc) {
	log_context nlc;

	nlc = memget(sizeof (struct log_context));
	if (nlc == NULL) {
		errno = ENOMEM;
		return (-1);
	}
	nlc->num_categories = num_categories;
	nlc->category_names = category_names;
	nlc->categories = memget(num_categories * sizeof (log_channel_list));
	if (nlc->categories == NULL) {
		memput(nlc, sizeof (struct log_context));
		errno = ENOMEM;
		return (-1);
	}
	memset(nlc->categories, '\0',
	       num_categories * sizeof (log_channel_list));
	nlc->flags = 0U;
	nlc->level = 0;
	*lc = nlc;
	return (0);
}

void
log_free_context(log_context lc) {
	log_channel_list lcl, lcl_next;
	log_channel chan;
	int i;

	REQUIRE(lc != NULL);

	for (i = 0; i < lc->num_categories; i++)
		for (lcl = lc->categories[i]; lcl != NULL; lcl = lcl_next) {
			lcl_next = lcl->next;
			chan = lcl->channel;
			(void)log_free_channel(chan);
			memput(lcl, sizeof (struct log_channel_list));
		}
	memput(lc->categories,
	       lc->num_categories * sizeof (log_channel_list));
	memput(lc, sizeof (struct log_context));
}

int
log_add_channel(log_context lc, int category, log_channel chan) {
	log_channel_list lcl;

	if (lc == NULL || category < 0 || category >= lc->num_categories) {
		errno = EINVAL;
		return (-1);
	}

	lcl = memget(sizeof (struct log_channel_list));
	if (lcl == NULL) {
		errno = ENOMEM;
		return(-1);
	}
	lcl->channel = chan;
	lcl->next = lc->categories[category];
	lc->categories[category] = lcl;
	chan->references++;
	return (0);
}

int
log_remove_channel(log_context lc, int category, log_channel chan) {
	log_channel_list lcl, prev_lcl, next_lcl;
	int found = 0;

	if (lc == NULL || category < 0 || category >= lc->num_categories) {
		errno = EINVAL;
		return (-1);
	}

	for (prev_lcl = NULL, lcl = lc->categories[category];
	     lcl != NULL;
	     lcl = next_lcl) {
		next_lcl = lcl->next;
		if (lcl->channel == chan) {
			log_free_channel(chan);
			if (prev_lcl != NULL)
				prev_lcl->next = next_lcl;
			else
				lc->categories[category] = next_lcl;
			memput(lcl, sizeof (struct log_channel_list));
			/*
			 * We just set found instead of returning because
			 * the channel might be on the list more than once.
			 */
			found = 1;
		} else
			prev_lcl = lcl;
	}
	if (!found) {
		errno = ENOENT;
		return (-1);
	}
	return (0);
}

int
log_option(log_context lc, int option, int value) {
	if (lc == NULL) {
		errno = EINVAL;
		return (-1);
	}
	switch (option) {
	case LOG_OPTION_DEBUG:
		if (value)
			lc->flags |= option;
		else
			lc->flags &= ~option;
		break;
	case LOG_OPTION_LEVEL:
		lc->level = value;
		break;
	default:
		errno = EINVAL;
		return (-1);
	}
	return (0);
}

int
log_category_is_active(log_context lc, int category) {
	if (lc == NULL) {
		errno = EINVAL;
		return (-1);
	}
	if (category >= 0 && category < lc->num_categories &&
	    lc->categories[category] != NULL)
		return (1);
	return (0);
}

log_channel
log_new_syslog_channel(unsigned int flags, int level, int facility) {
	log_channel chan;

	chan = memget(sizeof (struct log_channel));
	if (chan == NULL) {
		errno = ENOMEM;
		return (NULL);
	}
	chan->type = log_syslog;
	chan->flags = flags;
	chan->level = level;
	chan->out.facility = facility;
	chan->references = 0;
	return (chan);
}

log_channel
log_new_file_channel(unsigned int flags, int level,
		     const char *name, FILE *stream, unsigned int versions,
		     unsigned long max_size) {
	log_channel chan;

	chan = memget(sizeof (struct log_channel));
	if (chan == NULL) {
		errno = ENOMEM;
		return (NULL);
	}
	chan->type = log_file;
	chan->flags = flags;
	chan->level = level;
	if (name != NULL) {
		size_t len;
		
		len = strlen(name);
		/* 
		 * Quantize length to a multiple of 256.  There's space for the
		 * NUL, since if len is a multiple of 256, the size chosen will
		 * be the next multiple.
		 */
		chan->out.file.name_size = ((len / 256) + 1) * 256;
		chan->out.file.name = memget(chan->out.file.name_size);
		if (chan->out.file.name == NULL) {
			memput(chan, sizeof (struct log_channel));
			errno = ENOMEM;
			return (NULL);
		}
		/* This is safe. */
		strcpy(chan->out.file.name, name);
	} else {
		chan->out.file.name_size = 0;
		chan->out.file.name = NULL;
	}
	chan->out.file.stream = stream;
	chan->out.file.versions = versions;
	chan->out.file.max_size = max_size;
	chan->out.file.owner = getuid();
	chan->out.file.group = getgid();
	chan->references = 0;
	return (chan);
}

int
log_set_file_owner(log_channel chan, uid_t owner, gid_t group) {
	if (chan->type != log_file) {
		errno = EBADF;
		return (-1);
	}
	chan->out.file.owner = owner;
	chan->out.file.group = group;
	return (0);
}

log_channel
log_new_null_channel() {
	log_channel chan;

	chan = memget(sizeof (struct log_channel));
	if (chan == NULL) {
		errno = ENOMEM;
		return (NULL);
	}
	chan->type = log_null;
	chan->flags = LOG_CHANNEL_OFF;
	chan->level = log_info;
	chan->references = 0;
	return (chan);
}

int
log_inc_references(log_channel chan) {
	if (chan == NULL) {
		errno = EINVAL;
		return (-1);
	}
	chan->references++;
	return (0);
}

int
log_dec_references(log_channel chan) {
	if (chan == NULL || chan->references <= 0) {
		errno = EINVAL;
		return (-1);
	}
	chan->references--;
	return (0);
}

log_channel_type
log_get_channel_type(log_channel chan) {
	REQUIRE(chan != NULL);
	
	return (chan->type);
}

int
log_free_channel(log_channel chan) {
	if (chan == NULL || chan->references <= 0) {
		errno = EINVAL;
		return (-1);
	}
	chan->references--;
	if (chan->references == 0) {
		if (chan->type == log_file) {
			if ((chan->flags & LOG_CLOSE_STREAM) &&
			    chan->out.file.stream != NULL)
				(void)fclose(chan->out.file.stream);
			if (chan->out.file.name != NULL)
				memput(chan->out.file.name,
				       chan->out.file.name_size);
		}
		memput(chan, sizeof (struct log_channel));
	}
	return (0);
}