opkg: fallback to dest->root_dir if specified overlay_root does not exist on filesystem (#6498)

SVN-Revision: 19121

package/opkg/patches/003-fs_overlay_support.patch

@@ -26,22 +26,35 @@ Signed-off-by: Nicolas Thill <nico@openwrt.org>
       int noaction;
 --- a/libopkg/opkg_install.c
 +++ b/libopkg/opkg_install.c
-@@ -189,13 +189,19 @@
+@@ -21,6 +21,7 @@
+ #include <time.h>
+ #include <signal.h>
+ #include <unistd.h>
++#include <sys/stat.h>
+ 
+ #include "pkg.h"
+ #include "pkg_hash.h"
+@@ -189,13 +190,24 @@
  verify_pkg_installable(pkg_t *pkg)
  {
  	unsigned long kbs_available, pkg_size_kbs;
 -	char *root_dir;
 +	char *root_dir = NULL;
++	struct stat s;
  
  	if (conf->force_space || pkg->installed_size == 0)
  		return 0;
  
 -	root_dir = pkg->dest ? pkg->dest->root_dir :
 -						conf->default_dest->root_dir;
-+	if( !pkg->dest || !strcmp(pkg->dest->name, "root") )
-+		root_dir = conf->overlay_root;
-+	else
-+		root_dir = pkg->dest->root_dir;
++	if( pkg->dest )
++	{
++		if( !strcmp(pkg->dest->name, "root") && conf->overlay_root
++		    && !stat(conf->overlay_root, &s) && (s.st_mode & S_IFDIR) )
++			root_dir = conf->overlay_root;
++		else
++			root_dir = pkg->dest->root_dir;
++	}
 +
 +	if( !root_dir )
 +		root_dir = conf->default_dest->root_dir;