[PATCH]: xl: Check a domain exists before destroying it

[Gianni Tedesco <gianni.tedesco@citrix.com>]

On Mon, 2011-01-24 at 17:27 +0000, Christoph Egger wrote:
> > > 7. Too many error information showed when destroy an inexistent guest
> > > (Community) http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=1714
> >
> > A three line fix?
> 
> Already posted to this list:
> http://lists.xensource.com/archives/html/xen-devel/2011-01/msg01452.html

This is quite a clever fix but I think Ian Jacksons comments are
correct. We should do a libxl_domain_info() and bail early in the
destroy path if that fails.

---
xl: Check a domain exists before destroying it

Also fix a mis-formatted error message in xl destroy command.

Signed-off-by: Gianni Tedesco <gianni.tedesco@citrix.com>

diff -r b59f04eb8978 tools/libxl/libxl.c
--- a/tools/libxl/libxl.c	Fri Jan 21 18:06:23 2011 +0000
+++ b/tools/libxl/libxl.c	Mon Jan 24 17:39:33 2011 +0000
@@ -654,10 +654,21 @@ int libxl_event_get_disk_eject_info(libx
 int libxl_domain_destroy(libxl_ctx *ctx, uint32_t domid, int force)
 {
     libxl__gc gc = LIBXL_INIT_GC(ctx);
+    libxl_dominfo dominfo;
     char *dom_path;
     char *vm_path;
     int rc, dm_present;
 
+    rc = libxl_domain_info(ctx, &dominfo, domid);
+    switch(rc) {
+    case 0:
+        break;
+    case ERROR_INVAL:
+        LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "non-existant domain %d", domid);
+    default:
+        return rc;
+    }
+
     if (libxl__domain_is_hvm(ctx, domid)) {
         dm_present = 1;
     } else {
diff -r b59f04eb8978 tools/libxl/xl_cmdimpl.c
--- a/tools/libxl/xl_cmdimpl.c	Fri Jan 21 18:06:23 2011 +0000
+++ b/tools/libxl/xl_cmdimpl.c	Mon Jan 24 17:39:33 2011 +0000
@@ -2176,7 +2176,7 @@ static void destroy_domain(const char *p
         exit(-1);
     }
     rc = libxl_domain_destroy(&ctx, domid, 0);
-    if (rc) { fprintf(stderr,"destroy failed (rc=%d)\n.",rc); exit(-1); }
+    if (rc) { fprintf(stderr,"destroy failed (rc=%d).\n",rc); exit(-1); }
 }
 
 static void shutdown_domain(const char *p, int wait)