[tarantool-patches] [PATCH v4 1/4] Configurable syslog destination

[Olga Arkhangelskaia <arkholga@tarantool.org>]

Added server option to syslog configuration.
Server option is responsible for log destination. At the momemt
there is two ways of usage:server=unix:/path/to/socket or
server=ipv4:port. If port is not set default udp port 514 is used.
If logging to syslog is set, however there is no sever options -
default location is used: Linux /dev/log and Mac /var/run/syslog.

Closes #3487
---
 src/say.c | 103 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---
 src/say.h |  13 +++++++-
 2 files changed, 110 insertions(+), 6 deletions(-)

diff --git a/src/say.c b/src/say.c
index ac221dd19..526b8862f 100644
--- a/src/say.c
+++ b/src/say.c
@@ -36,6 +36,7 @@
 #include <stdarg.h>
 #include <stdio.h>
 #include <string.h>
+#include <netdb.h>
 #include <sys/types.h>
 #include <unistd.h>
 #include <fcntl.h>
@@ -45,6 +46,7 @@
 #include <arpa/inet.h>
 #include <coio_task.h>
 
+#define DEFAULT_PORT 514
 pid_t log_pid = 0;
 int log_level = S_INFO;
 enum say_format log_format = SF_PLAIN;
@@ -473,16 +475,85 @@ syslog_connect_unix(const char *path)
 	return fd;
 }
 
+/**
+ * Connect to remote syslogd using server:port.
+ * @param server address string of remote host.
+ * @retval not 0 Socket descriptor.
+ * @retval    -1 Socket error.
+ */
+static int
+syslog_connect_remote(const char *server_address)
+{
+	struct addrinfo *inf, hints, *ptr;
+	const char *remote;
+	char buf[10];
+	char *portnum, *copy;
+	int fd = -1;
+
+	copy = strdup(server_address);
+	if (copy == NULL) {
+		diag_set(OutOfMemory, strlen(server_address), "malloc",
+			 "stslog server address");
+		return fd;
+	}
+	portnum = copy;
+	remote = strsep(&portnum, ":");
+	if (portnum == NULL) {
+		snprintf(buf, sizeof(buf), "%d", DEFAULT_PORT);
+		portnum = buf;
+	}
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = AF_INET;
+	hints.ai_socktype = SOCK_DGRAM;
+	hints.ai_protocol = IPPROTO_UDP;
+
+	if (getaddrinfo(remote, (const char*)portnum, NULL, &inf) < 0) {
+		diag_set(SystemError, "syslog: getaddrinfo failed %s",
+			 gai_strerror(errno));
+		goto out;
+	}
+	for (ptr = inf; ptr; ptr = ptr->ai_next) {
+		fd = socket(ptr->ai_family, ptr->ai_socktype, ptr->ai_protocol);
+		if (fd < 0) {
+			diag_set(SystemError, "syslog: socket failed %s",
+				 strerror(errno));
+			continue;
+		}
+		if (connect(fd, inf->ai_addr, inf->ai_addrlen) != 0) {
+			close(fd);
+			fd = -1;
+			diag_set(SystemError, "syslog:connect failed %s",
+				 strerror(errno));
+			continue;
+		}
+		break;
+	}
+	freeaddrinfo(inf);
+out:
+	free(copy);
+	return fd;
+}
+
 static inline int
 log_syslog_connect(struct log *log)
 {
 	/*
-	 * Try two locations: '/dev/log' for Linux and
+	 * If server option is not set use '/dev/log' for Linux and
 	 * '/var/run/syslog' for Mac.
 	 */
-	log->fd = syslog_connect_unix("/dev/log");
-	if (log->fd < 0)
-		log->fd = syslog_connect_unix("/var/run/syslog");
+	switch (log->server_type) {
+	case SAY_SYSLOG_UNIX:
+		log->fd = syslog_connect_unix(log->path);
+		break;
+	case SAY_SYSLOG_REMOTE:
+		log->fd = syslog_connect_remote(log->path);
+		break;
+	default:
+		log->fd = syslog_connect_unix("/dev/log");
+		if (log->fd < 0)
+			log->fd = syslog_connect_unix("/var/run/syslog");
+
+	}
 	return log->fd;
 }
 
@@ -498,6 +569,15 @@ log_syslog_init(struct log *log, const char *init_str)
 	if (say_parse_syslog_opts(init_str, &opts) < 0)
 		return -1;
 
+	log->server_type = opts.server_type;
+	if (log->server_type != SAY_SYSLOG_DEFAULT) {
+		log->path = strdup(opts.server_path);
+		if (log->path == NULL) {
+			diag_set(OutOfMemory, strlen(opts.server_path),
+				 "malloc", "server address");
+			return -1;
+		}
+	}
 	if (opts.identity == NULL)
 		log->syslog_ident = strdup("tarantool");
 	else
@@ -1031,6 +1111,8 @@ say_syslog_facility_by_name(const char *facility)
 int
 say_parse_syslog_opts(const char *init_str, struct say_syslog_opts *opts)
 {
+	opts->server_path = NULL;
+	opts->server_type = SAY_SYSLOG_DEFAULT;
 	opts->identity = NULL;
 	opts->facility = syslog_facility_MAX;
 	opts->copy = strdup(init_str);
@@ -1047,7 +1129,18 @@ say_parse_syslog_opts(const char *init_str, struct say_syslog_opts *opts)
 			break;
 
 		value = option;
-		if (say_parse_prefix(&value, "identity=")) {
+		if (say_parse_prefix(&value, "server=")) {
+			if (opts->server_path != NULL ||
+			    opts->server_type != SAY_SYSLOG_DEFAULT)
+				goto duplicate;
+			if (say_parse_prefix(&value, "unix:")) {
+				opts->server_type = SAY_SYSLOG_UNIX;
+				opts->server_path = value;
+			} else {
+				opts->server_type = SAY_SYSLOG_REMOTE;
+				opts->server_path = value;
+			}
+		} else if (say_parse_prefix(&value, "identity=")) {
 			if (opts->identity != NULL)
 				goto duplicate;
 			opts->identity = value;
diff --git a/src/say.h b/src/say.h
index 2c2395fe0..73697b1b7 100644
--- a/src/say.h
+++ b/src/say.h
@@ -79,6 +79,12 @@ say_log_level_is_enabled(int level)
 
 extern enum say_format log_format;
 
+enum say_logger_syslog_server {
+	SAY_SYSLOG_DEFAULT,
+	SAY_SYSLOG_UNIX,
+	SAY_SYSLOG_REMOTE
+};
+
 enum say_logger_type {
 	/**
 	 * Before the app server core is initialized, we do not
@@ -141,7 +147,10 @@ struct log {
 	/** The current log level. */
 	int level;
 	enum say_logger_type type;
-	/** path to file if logging to file. */
+	enum say_logger_syslog_server server_type;
+	/** Path to file if logging to file, socket
+	 *  or server address in case of syslog.
+	 */
 	char *path;
 	bool nonblock;
 	log_format_func_t format_func;
@@ -384,6 +393,8 @@ say_parse_logger_type(const char **str, enum say_logger_type *type);
 
 /** Syslog logger initialization params */
 struct say_syslog_opts {
+	enum say_logger_syslog_server server_type;
+	const char *server_path;
 	const char *identity;
 	enum syslog_facility facility;
 	/* Input copy (content unspecified). */
-- 
2.14.3 (Apple Git-98)