From e95dd8e99188377bb6351fc0a4ceb4e790612044 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Tue, 22 Nov 2022 12:42:46 +0100
Subject: [PATCH] varlink: also handle EINTR gracefully when waiting for EIO
 via ppoll()

(cherry picked from commit 6976bf5cd614761eb4bd57d39e24f7eca1d6b863)

Related: #2137584
---
 src/shared/varlink.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/shared/varlink.c b/src/shared/varlink.c
index 4f7ac97689..4d2cfee491 100644
--- a/src/shared/varlink.c
+++ b/src/shared/varlink.c
@@ -1025,7 +1025,7 @@ static void handle_revents(Varlink *v, int revents) {
                 if ((revents & (POLLOUT|POLLHUP)) == 0)
                         return;
 
-                varlink_log(v, "Anynchronous connection completed.");
+                varlink_log(v, "Asynchronous connection completed.");
                 v->connecting = false;
         } else {
                 /* Note that we don't care much about POLLIN/POLLOUT here, we'll just try reading and writing
@@ -1075,6 +1075,9 @@ int varlink_wait(Varlink *v, usec_t timeout) {
                 return events;
 
         r = fd_wait_for_event(fd, events, t);
+        if (r < 0 && ERRNO_IS_TRANSIENT(r)) /* Treat EINTR as not a timeout, but also nothing happened, and
+                                             * the caller gets a chance to call back into us */
+                return 1;
         if (r <= 0)
                 return r;
 
@@ -1161,8 +1164,12 @@ int varlink_flush(Varlink *v) {
                 }
 
                 r = fd_wait_for_event(v->fd, POLLOUT, USEC_INFINITY);
-                if (r < 0)
+                if (r < 0) {
+                        if (ERRNO_IS_TRANSIENT(r))
+                                continue;
+
                         return varlink_log_errno(v, r, "Poll failed on fd: %m");
+                }
 
                 assert(r != 0);