From 23b1e5c0b0e0be4e45e96bfb9da2b11e23dce916 Mon Sep 17 00:00:00 2001
From: Chris Lalancette <clalance@redhat.com>
Date: Fri, 2 Apr 2010 21:24:50 -0400
Subject: [PATCH] Better error reporting in virsh.

When hitting failures in virsh, a common idiom is
to jump to a cleanup label, free some resources, and
then return a FALSE error code to vshCommandRun.
In theory, vshCommandRun is then supposed to print
out the last error.  The problem is that many of
the cleanup paths have library calls to free resources,
and all of those library calls clear out the last error.
This is leading to situations where no error is being
reported at all.

This patch remedies the situation somewhat by
printing out the errors inside the command methods
themselves when we know it will go through a cleanup
path that will lose the error.

Signed-off-by: Chris Lalancette <clalance@redhat.com>
---
 tools/virsh.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/tools/virsh.c b/tools/virsh.c
index ad64bc0d18..c7551fde3a 100644
--- a/tools/virsh.c
+++ b/tools/virsh.c
@@ -2622,9 +2622,8 @@ cmdDomXMLFromNative(vshControl *ctl, const vshCmd *cmd)
     format = vshCommandOptString(cmd, "format", NULL);
     configFile = vshCommandOptString(cmd, "config", NULL);
 
-    if (virFileReadAll(configFile, 1024*1024, &configData) < 0) {
+    if (virFileReadAll(configFile, 1024*1024, &configData) < 0)
         return FALSE;
-    }
 
     xmlData = virConnectDomainXMLFromNative(ctl->conn, format, configData, flags);
     if (xmlData != NULL) {
@@ -2668,9 +2667,8 @@ cmdDomXMLToNative(vshControl *ctl, const vshCmd *cmd)
     format = vshCommandOptString(cmd, "format", NULL);
     xmlFile = vshCommandOptString(cmd, "xml", NULL);
 
-    if (virFileReadAll(xmlFile, 1024*1024, &xmlData) < 0) {
+    if (virFileReadAll(xmlFile, 1024*1024, &xmlData) < 0)
         return FALSE;
-    }
 
     configData = virConnectDomainXMLToNative(ctl->conn, format, xmlData, flags);
     if (configData != NULL) {
@@ -4329,9 +4327,8 @@ cmdNodeDeviceCreate(vshControl *ctl, const vshCmd *cmd)
         return FALSE;
     }
 
-    if (virFileReadAll(from, VIRSH_MAX_XML_FILE, &buffer) < 0) {
+    if (virFileReadAll(from, VIRSH_MAX_XML_FILE, &buffer) < 0)
         return FALSE;
-    }
 
     dev = virNodeDeviceCreateXML(ctl->conn, buffer, 0);
     VIR_FREE(buffer);
@@ -5426,6 +5423,7 @@ cmdVolCreate(vshControl *ctl, const vshCmd *cmd)
     }
 
     if (virFileReadAll(from, VIRSH_MAX_XML_FILE, &buffer) < 0) {
+        virshReportError(ctl);
         virStoragePoolFree(pool);
         return FALSE;
     }
@@ -5487,6 +5485,7 @@ cmdVolCreateFrom(vshControl *ctl, const vshCmd *cmd)
         goto cleanup;
 
     if (virFileReadAll(from, VIRSH_MAX_XML_FILE, &buffer) < 0) {
+        virshReportError(ctl);
         goto cleanup;
     }
 
@@ -6927,6 +6926,7 @@ cmdAttachDevice(vshControl *ctl, const vshCmd *cmd)
     }
 
     if (virFileReadAll(from, VIRSH_MAX_XML_FILE, &buffer) < 0) {
+        virshReportError(ctl);
         virDomainFree(dom);
         return FALSE;
     }
@@ -6994,6 +6994,7 @@ cmdDetachDevice(vshControl *ctl, const vshCmd *cmd)
     }
 
     if (virFileReadAll(from, VIRSH_MAX_XML_FILE, &buffer) < 0) {
+        virshReportError(ctl);
         virDomainFree(dom);
         return FALSE;
     }
@@ -7061,6 +7062,7 @@ cmdUpdateDevice(vshControl *ctl, const vshCmd *cmd)
     }
 
     if (virFileReadAll(from, VIRSH_MAX_XML_FILE, &buffer) < 0) {
+        virshReportError(ctl);
         virDomainFree(dom);
         return FALSE;
     }