conf: Rework code around 'append' attribute

Commit id '70ffa02f' added the data.file.append option to some
VIR_DOMAIN_CHR_TYPE_FILE cases in switch statements allowing the
code to "fall through" for the remainder of the cases. This causes
angst in code profiling tools, like Coverity since there is no break;
followed by more case conditions. Adjust the logic to be more specific
within each case.
Signed-off-by: NDmitry Mishin <dim@virtuozzo.com>

src/conf/domain_conf.c

@@ -1723,10 +1723,11 @@ virDomainChrSourceDefCopy(virDomainChrSourceDefPtr dest,
 
     switch (src->type) {
     case VIR_DOMAIN_CHR_TYPE_FILE:
-        dest->data.file.append = src->data.file.append;
     case VIR_DOMAIN_CHR_TYPE_PTY:
     case VIR_DOMAIN_CHR_TYPE_DEV:
     case VIR_DOMAIN_CHR_TYPE_PIPE:
+        if (src->type == VIR_DOMAIN_CHR_TYPE_FILE)
+            dest->data.file.append = src->data.file.append;
         if (VIR_STRDUP(dest->data.file.path, src->data.file.path) < 0)
             return -1;
         break;
@@ -9386,12 +9387,12 @@ virDomainChrSourceDefParseXML(virDomainChrSourceDefPtr def,
 
                 switch ((virDomainChrType) def->type) {
                 case VIR_DOMAIN_CHR_TYPE_FILE:
-                    if (!append)
-                        append = virXMLPropString(cur, "append");
                 case VIR_DOMAIN_CHR_TYPE_PTY:
                 case VIR_DOMAIN_CHR_TYPE_DEV:
                 case VIR_DOMAIN_CHR_TYPE_PIPE:
                 case VIR_DOMAIN_CHR_TYPE_UNIX:
+                    if (!append && def->type == VIR_DOMAIN_CHR_TYPE_FILE)
+                        append = virXMLPropString(cur, "append");
                     /* PTY path is only parsed from live xml.  */
                     if (!path  &&
                         (def->type != VIR_DOMAIN_CHR_TYPE_PTY ||
@@ -9476,15 +9477,15 @@ virDomainChrSourceDefParseXML(virDomainChrSourceDefPtr def,
         break;
 
     case VIR_DOMAIN_CHR_TYPE_FILE:
-        if (append &&
+    case VIR_DOMAIN_CHR_TYPE_PTY:
+    case VIR_DOMAIN_CHR_TYPE_DEV:
+    case VIR_DOMAIN_CHR_TYPE_PIPE:
+        if (append && def->type == VIR_DOMAIN_CHR_TYPE_FILE &&
             (def->data.file.append = virTristateSwitchTypeFromString(append)) <= 0) {
             virReportError(VIR_ERR_INTERNAL_ERROR,
                            _("Invalid append attribute value '%s'"), append);
             goto error;
         }
-    case VIR_DOMAIN_CHR_TYPE_PTY:
-    case VIR_DOMAIN_CHR_TYPE_DEV:
-    case VIR_DOMAIN_CHR_TYPE_PIPE:
         if (!path &&
             def->type != VIR_DOMAIN_CHR_TYPE_PTY) {
             virReportError(VIR_ERR_INTERNAL_ERROR, "%s",