Fixing application process infinite loop.

Main process exiting before app process init may have caused hanging.

go/port.go

@@ -138,6 +138,8 @@ func nxt_go_port_send(pid C.int, id C.int, buf unsafe.Pointer, buf_size C.int,
 
 	if err != nil {
 		nxt_go_warn("write result %d (%d), %s", n, oobn, err)
+
+		n = -1
 	}
 
 	return C.ssize_t(n)
@@ -164,6 +166,8 @@ func nxt_go_port_recv(pid C.int, id C.int, buf unsafe.Pointer, buf_size C.int,
 
 	if err != nil {
 		nxt_go_warn("read result %d (%d), %s", n, oobn, err)
+
+		n = -1
 	}
 
 	return C.ssize_t(n)

src/nxt_unit.c

@@ -2635,7 +2635,6 @@ nxt_unit_buf_read(nxt_unit_buf_t **b, uint64_t *len, void *dst, size_t size)
 void
 nxt_unit_request_done(nxt_unit_request_info_t *req, int rc)
 {
-    ssize_t                       res;
     uint32_t                      size;
     nxt_port_msg_t                msg;
     nxt_unit_impl_t               *lib;
@@ -2690,12 +2689,8 @@ skip_response_send:
     msg.mf = 0;
     msg.tracking = 0;
 
-    res = lib->callbacks.port_send(req->ctx, &req->response_port,
+    (void) lib->callbacks.port_send(req->ctx, &req->response_port,
                                     &msg, sizeof(msg), NULL, 0);
-    if (nxt_slow_path(res != sizeof(msg))) {
-        nxt_unit_req_alert(req, "last message send failed: %s (%d)",
-                           strerror(errno), errno);
-    }
 
     nxt_unit_request_info_release(req);
 }
@@ -3013,9 +3008,6 @@ nxt_unit_send_oosm(nxt_unit_ctx_t *ctx, nxt_unit_port_id_t *port_id)
 
     res = lib->callbacks.port_send(ctx, port_id, &msg, sizeof(msg), NULL, 0);
     if (nxt_slow_path(res != sizeof(msg))) {
-        nxt_unit_warn(ctx, "failed to send oosm to %d: %s (%d)",
-                      (int) port_id->pid, strerror(errno), errno);
-
         return NXT_UNIT_ERROR;
     }
 
@@ -3039,6 +3031,7 @@ nxt_unit_wait_shm_ack(nxt_unit_ctx_t *ctx)
         }
 
         nxt_unit_read_buf(ctx, rbuf);
+
         if (nxt_slow_path(rbuf->size < (ssize_t) sizeof(nxt_port_msg_t))) {
             nxt_unit_read_buf_release(ctx, rbuf);
 
@@ -3294,9 +3287,6 @@ nxt_unit_send_mmap(nxt_unit_ctx_t *ctx, nxt_unit_port_id_t *port_id, int fd)
     res = lib->callbacks.port_send(ctx, port_id, &msg, sizeof(msg),
                                    &cmsg, sizeof(cmsg));
     if (nxt_slow_path(res != sizeof(msg))) {
-        nxt_unit_warn(ctx, "failed to send shm to %d: %s (%d)",
-                      (int) port_id->pid, strerror(errno), errno);
-
         return NXT_UNIT_ERROR;
     }
 
@@ -3739,9 +3729,6 @@ nxt_unit_send_shm_ack(nxt_unit_ctx_t *ctx, pid_t pid)
 
     res = lib->callbacks.port_send(ctx, &port_id, &msg, sizeof(msg), NULL, 0);
     if (nxt_slow_path(res != sizeof(msg))) {
-        nxt_unit_warn(ctx, "failed to send ack to %d: %s (%d)",
-                      (int) port_id.pid, strerror(errno), errno);
-
         return NXT_UNIT_ERROR;
     }
 
@@ -3894,6 +3881,10 @@ nxt_unit_run(nxt_unit_ctx_t *ctx)
 
     while (nxt_fast_path(lib->online)) {
         rc = nxt_unit_run_once(ctx);
+
+        if (nxt_slow_path(rc != NXT_UNIT_OK)) {
+            break;
+        }
     }
 
     return rc;
@@ -4552,14 +4543,24 @@ nxt_unit_port_send(nxt_unit_ctx_t *ctx, int fd,
     msg.msg_control = (void *) oob;
     msg.msg_controllen = oob_size;
 
+retry:
+
     res = sendmsg(fd, &msg, 0);
 
     if (nxt_slow_path(res == -1)) {
-        nxt_unit_warn(ctx, "port_send(%d, %d) failed: %s (%d)",
+        if (errno == EINTR) {
+            goto retry;
+        }
+
+        /*
+         * FIXME: This should be "alert" after router graceful shutdown
+         * implementation.
+         */
+        nxt_unit_warn(ctx, "sendmsg(%d, %d) failed: %s (%d)",
                       fd, (int) buf_size, strerror(errno), errno);
 
     } else {
-        nxt_unit_debug(ctx, "port_send(%d, %d): %d", fd, (int) buf_size,
+        nxt_unit_debug(ctx, "sendmsg(%d, %d): %d", fd, (int) buf_size,
                        (int) res);
     }
 
@@ -4629,14 +4630,20 @@ nxt_unit_port_recv(nxt_unit_ctx_t *ctx, int fd, void *buf, size_t buf_size,
     msg.msg_control = oob;
     msg.msg_controllen = oob_size;
 
+retry:
+
     res = recvmsg(fd, &msg, 0);
 
     if (nxt_slow_path(res == -1)) {
-        nxt_unit_warn(ctx, "port_recv(%d) failed: %s (%d)",
+        if (errno == EINTR) {
+            goto retry;
+        }
+
+        nxt_unit_alert(ctx, "recvmsg(%d) failed: %s (%d)",
                        fd, strerror(errno), errno);
 
     } else {
-        nxt_unit_debug(ctx, "port_recv(%d): %d", fd, (int) res);
+        nxt_unit_debug(ctx, "recvmsg(%d): %d", fd, (int) res);
     }
 
     return res;

test/test_node_websockets.py

@@ -22,7 +22,7 @@ class TestNodeWebsockets(TestApplicationNode):
         )
 
         self.skip_alerts.extend(
-            [r'last message send failed', r'socket close\(\d+\) failed']
+            [r'socket close\(\d+\) failed']
         )
 
     def close_connection(self, sock):

test/unit/main.py

@@ -193,7 +193,6 @@ class TestUnit(unittest.TestCase):
 
         self.skip_alerts = [
             r'read signalfd\(4\) failed',
-            r'last message send failed',
             r'sendmsg.+failed',
             r'recvmsg.+failed',
         ]