From: Stefan Berger <stefanb@linux.vnet.ibm.com>
Date: Thu, 25 Jul 2019 18:22:08 +0000 (-0400)
Subject: utils: Mark inpipe as non-blocking
X-Git-Tag: v5.6.0-rc1~50
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7f940d74972485d23d8d0bc04a72e5b689076a8f;p=thirdparty%2Flibvirt.git

utils: Mark inpipe as non-blocking

Mark a virCommand's inpipe (write-end of pipe) as non-blocking so that it
will never block when we were to try to write too many bytes to it while
it doesn't have the capacity to hold them.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
---

diff --git a/src/util/vircommand.c b/src/util/vircommand.c
index 94b2ebc8aa..a3a5780d29 100644
--- a/src/util/vircommand.c
+++ b/src/util/vircommand.c
@@ -2538,6 +2538,19 @@ virCommandRunAsync(virCommandPtr cmd, pid_t *pid)
         }
         cmd->infd = infd[0];
         cmd->inpipe = infd[1];
+#if defined (F_SETFL)
+        if (fcntl(cmd->inpipe, F_SETFL, O_NONBLOCK) < 0) {
+            virReportSystemError(errno, "%s",
+                                 _("fcntl failed to set O_NONBLOCK"));
+            cmd->has_error = -1;
+            ret = -1;
+            goto cleanup;
+        }
+#else /* !defined(F_SETFL) */
+        cmd->has_error = ENOTSUP;
+        ret = -1;
+        goto cleanup;
+#endif
     } else if ((cmd->inbuf && cmd->infd == -1) ||
                (cmd->outbuf && cmd->outfdptr != &cmd->outfd) ||
                (cmd->errbuf && cmd->errfdptr != &cmd->errfd)) {