[libvirt] [PATCH v2] libvirt_iohelper: record the libvirt_iohelper's error message at virFileWrapperFdFree

[xinhua.Cao]

Currently iohelper's error log is recorded in virFileWrapperFdClose.
In qemuDomainSaveMemory, it usually fails at qemuMigrationSrcToFile,
and then goto cleanup, so the iohelper error log is not recorded,
and so is the another placement. We now record the error log of
iohelper by move it to the virFileWrapperFdFree record.
And for the virCommandWait() - we should call virCommandAbort() in
virFileWrapperFdFree() to make sure no process is left behind. If
virCommandWait() is called then virCommandAbort() is a NO-OP. If it
isn't, then Abort() will kill iohelper. Thanks for Michal for this
advice

Signed-off-by: xinhua.Cao <caoxinhua at huawei.com>
---
 src/util/virfile.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/util/virfile.c b/src/util/virfile.c
index 1faeebb..590fc0e 100644
--- a/src/util/virfile.c
+++ b/src/util/virfile.c
@@ -330,9 +330,6 @@ virFileWrapperFdClose(virFileWrapperFdPtr wfd)
         return 0;
 
     ret = virCommandWait(wfd->cmd, NULL);
-    if (wfd->err_msg && *wfd->err_msg)
-        VIR_WARN("iohelper reports: %s", wfd->err_msg);
-
     return ret;
 }
 
@@ -351,6 +348,10 @@ virFileWrapperFdFree(virFileWrapperFdPtr wfd)
     if (!wfd)
         return;
 
+    if (wfd->err_msg && *wfd->err_msg)
+        VIR_WARN("iohelper reports: %s", wfd->err_msg);
+
+    virCommandAbort(wfd->cmd);
     VIR_FREE(wfd->err_msg);
 
     virCommandFree(wfd->cmd);
-- 
2.8.3