F #4985: Fix ssh/cpds for qcow2 disk of stopped VM (#891)

If disk has RECOVERY_SNAPSHOT_FREQ attr, it's a
qcow2 backing chain (2). Convert it to a single
qcow2 first.

src/mad/sh/scripts_common.sh

@@ -478,6 +478,7 @@ ssh_forward()
 }
 
 #This function executes $2 at $1 host and report error $3 but does not exit
+#Accept $4 as alternative correct return code
 function ssh_exec_and_log_no_error
 {
     SSH_EXEC_ERR=`$SSH $1 bash -s 2>&1 1>/dev/null <<EOF
@@ -487,7 +488,7 @@ $2
 EOF`
     SSH_EXEC_RC=$?
 
-    if [ $SSH_EXEC_RC -ne 0 ]; then
+    if [ $SSH_EXEC_RC -ne 0 ] && [ $SSH_EXEC_RC != "$4" ]; then
         log_error "Command \"$2\" failed: $SSH_EXEC_ERR"
 
         if [ -n "$3" ]; then
@@ -496,10 +497,9 @@ EOF`
             error_message "Error executing $2: $SSH_EXEC_ERR"
         fi
 
-        return $SSH_EXEC_RC
     fi
 
-    return 0
+    return $SSH_EXEC_RC
 }
 
 #This function executes $2 at $1 host and report error $3

src/tm_mad/ssh/cpds

@@ -124,7 +124,7 @@ EOF
     CPDS_CMD_ERR="Error creating export for domain ${DEPLOY_ID} of disk ${DISK_TARGET} at ${SRC_TEMP_PATH}"
 
     # Always try delete temp export
-    trap "ssh_exec_and_log $SRC_HOST \"$RM ${SRC_TEMP_PATH}\"" EXIT TERM INT HUP
+    trap "ssh_exec_and_log $SRC_HOST \"$RM ${SRC_TEMP_PATH}\"" EXIT
 
     if ssh_exec_and_log_no_error $SRC_HOST "$CPDS_CMD_EXPORT" "$CPDS_CMD_ERR"; then
         # Export creation succeeded, point SRC there
@@ -134,6 +134,33 @@ EOF
         log_error "Exporting failed"
         exit 1
     fi
+else
+    # if SRC is qcow2 with backing chain, convert it to tmp path
+    CPDS_CMD_EXPORT=$(cat <<EOF
+        set -e -o pipefail
+        if [ -L $SRC_PATH ] && file -L $SRC_PATH | grep -q 'has backing file'; then
+            $QEMU_IMG convert -O qcow2 $SRC_PATH $SRC_TEMP_PATH;
+            exit 42;
+        fi
+EOF
+)
+
+    ssh_exec_and_log_no_error $SRC_HOST "$CPDS_CMD_EXPORT" "$CPDS_CMD_ERR" "100"
+    RC=$?
+    if [ $RC = 0 ]; then
+        # no export needed
+        true
+    elif [ $RC = 42 ]; then
+        # qcow2 detected and exported, re-point SRC and other vars
+        SRC="${SRC_HOST}:${SRC_TEMP_PATH}"
+        set_src_dst_vars
+
+        # Always try delete temp export
+        trap "ssh_exec_and_log $SRC_HOST \"$RM ${SRC_TEMP_PATH}\"" EXIT
+    else
+        error_message "Can not convert qcow2 chain $SRC_PATH"
+        exit 1
+    fi
 fi
 
 log "Moving $SRC to datastore as $DST_PATH"