[Tarantool-patches] [PATCH v2 1/2] coio/say: fix getaddrinfo error handling on macOS

[Roman Khabibov <roman.habibov@tarantool.org>]

Before this patch, branch when getaddrinfo() returns error codes
couldn't be reached on macOS, because they are greater than 0 on
macOS (assumption "rc < 0" in commit ea1da04 is incorrect for
macOS).

Note: diag_log() in say.c was added, because otherwise it will be
hid by the following diagnostic and it should be handled in a
better way after #1148. Also, two diag_set() in
syslog_connect_unix() was added to avoid asserts in this
diag_log().

Need for #4138
---
 src/lib/core/coio_task.c |  2 +-
 src/lib/core/say.c       | 12 ++++++++++--
 test/unit/coio.cc        | 29 ++++++++++++++++++++++++++++-
 test/unit/coio.result    |  4 +++-
 4 files changed, 42 insertions(+), 5 deletions(-)

diff --git a/src/lib/core/coio_task.c b/src/lib/core/coio_task.c
index 908b336ed..83f669d05 100644
--- a/src/lib/core/coio_task.c
+++ b/src/lib/core/coio_task.c
@@ -413,7 +413,7 @@ coio_getaddrinfo(const char *host, const char *port,
 		return -1; /* timed out or cancelled */
 
 	/* Task finished */
-	if (task->rc < 0) {
+	if (task->rc != 0) {
 		/* getaddrinfo() failed */
 		errno = EIO;
 		diag_set(SystemError, "getaddrinfo: %s",
diff --git a/src/lib/core/say.c b/src/lib/core/say.c
index 64a637c58..8ad88ad57 100644
--- a/src/lib/core/say.c
+++ b/src/lib/core/say.c
@@ -459,14 +459,17 @@ static inline int
 syslog_connect_unix(const char *path)
 {
 	int fd = socket(PF_UNIX, SOCK_DGRAM, 0);
-	if (fd < 0)
+	if (fd < 0) {
+		diag_set(SystemError, "socket");
 		return -1;
+	}
 	struct sockaddr_un un;
 	memset(&un, 0, sizeof(un));
 	snprintf(un.sun_path, sizeof(un.sun_path), "%s", path);
 	un.sun_family = AF_UNIX;
 	if (connect(fd, (struct sockaddr *) &un, sizeof(un)) != 0) {
 		close(fd);
+		diag_set(SystemError, "connect");
 		return -1;
 	}
 	return fd;
@@ -506,7 +509,7 @@ syslog_connect_remote(const char *server_address)
 	hints.ai_protocol = IPPROTO_UDP;
 
 	ret = getaddrinfo(remote, portnum, &hints, &inf);
-	if (ret < 0) {
+	if (ret != 0) {
 		errno = EIO;
 		diag_set(SystemError, "getaddrinfo: %s",
 			 gai_strerror(ret));
@@ -593,6 +596,11 @@ log_syslog_init(struct log *log, const char *init_str)
 	say_free_syslog_opts(&opts);
 	log->fd = log_syslog_connect(log);
 	if (log->fd < 0) {
+		/*
+		 * We need to log a diagnostics here until stacked
+		 * diagnostics will be implemented (#1148).
+		 */
+		diag_log();
 		/* syslog indent is freed in atexit(). */
 		diag_set(SystemError, "syslog logger: %s", strerror(errno));
 		return -1;
diff --git a/test/unit/coio.cc b/test/unit/coio.cc
index bb8bd7131..957c58ede 100644
--- a/test/unit/coio.cc
+++ b/test/unit/coio.cc
@@ -72,7 +72,7 @@ static void
 test_getaddrinfo(void)
 {
 	header();
-	plan(1);
+	plan(3);
 	const char *host = "127.0.0.1";
 	const char *port = "3333";
 	struct addrinfo *i;
@@ -81,6 +81,33 @@ test_getaddrinfo(void)
 	is(rc, 0, "getaddrinfo");
 	freeaddrinfo(i);
 
+	/*
+	 * gh-4138: Check getaddrinfo() retval and diagnostics
+	 * area.
+	 */
+	rc = coio_getaddrinfo("non_exists_hostname", port, NULL, &i,
+			      15768000000);
+	isnt(rc, 0, "getaddrinfo retval");
+	const char *errmsg = diag_get()->last->errmsg;
+	const char *exp_errmsg_1 = "getaddrinfo: nodename nor servname provided"
+		", or not known";
+	const char *exp_errmsg_2 = "getaddrinfo: Servname not supported for "
+		"ai_socktype";
+	const char *exp_errmsg_3 = "getaddrinfo: Name or service not known";
+	const char *exp_errmsg_4 = "getaddrinfo: hostname nor servname provided"
+		", or not known";
+	const char *exp_errmsg_5 = "getaddrinfo: Temporary failure in name "
+		"resolution";
+	const char *exp_errmsg_6 = "getaddrinfo: Name could not be resolved at "
+		"this time";
+	bool is_match_with_exp = strcmp(errmsg, exp_errmsg_1) == 0 ||
+		strcmp(errmsg, exp_errmsg_2) == 0 ||
+		strcmp(errmsg, exp_errmsg_3) == 0 ||
+		strcmp(errmsg, exp_errmsg_4) == 0 ||
+		strcmp(errmsg, exp_errmsg_5) == 0 ||
+		strcmp(errmsg, exp_errmsg_6) == 0;
+	is(is_match_with_exp, true, "getaddrinfo error message");
+
 	/*
 	 * gh-4209: 0 timeout should not be a special value and
 	 * detach a task. Before a fix it led to segfault
diff --git a/test/unit/coio.result b/test/unit/coio.result
index 5019fa48a..90b567140 100644
--- a/test/unit/coio.result
+++ b/test/unit/coio.result
@@ -7,6 +7,8 @@
 # call done with res 0
 	*** test_call_f: done ***
 	*** test_getaddrinfo ***
-1..1
+1..3
 ok 1 - getaddrinfo
+ok 2 - getaddrinfo retval
+ok 3 - getaddrinfo error message
 	*** test_getaddrinfo: done ***
-- 
2.21.0 (Apple Git-122)