--- a/libopkg/opkg_conf.c
+++ b/libopkg/opkg_conf.c
-@@ -72,6 +72,7 @@
- { "offline_root_path", OPKG_OPT_TYPE_STRING, &conf->offline_root_path },
- { "offline_root_post_script_cmd", OPKG_OPT_TYPE_STRING, &conf->offline_root_post_script_cmd },
- { "offline_root_pre_script_cmd", OPKG_OPT_TYPE_STRING, &conf->offline_root_pre_script_cmd },
-+ { "overlay_root", OPKG_OPT_TYPE_STRING, &conf->overlay_root },
- { "proxy_passwd", OPKG_OPT_TYPE_STRING, &conf->proxy_passwd },
- { "proxy_user", OPKG_OPT_TYPE_STRING, &conf->proxy_user },
- { "query-all", OPKG_OPT_TYPE_BOOL, &conf->query_all },
+@@ -62,6 +62,7 @@ opkg_option_t options[] = {
+ { "download_only", OPKG_OPT_TYPE_BOOL, &_conf.download_only },
+ { "nodeps", OPKG_OPT_TYPE_BOOL, &_conf.nodeps },
+ { "offline_root", OPKG_OPT_TYPE_STRING, &_conf.offline_root },
++ { "overlay_root", OPKG_OPT_TYPE_STRING, &_conf.overlay_root },
+ { "proxy_passwd", OPKG_OPT_TYPE_STRING, &_conf.proxy_passwd },
+ { "proxy_user", OPKG_OPT_TYPE_STRING, &_conf.proxy_user },
+ { "query-all", OPKG_OPT_TYPE_BOOL, &_conf.query_all },
--- a/libopkg/opkg_conf.h
+++ b/libopkg/opkg_conf.h
-@@ -70,6 +70,7 @@
- char *offline_root_path;
- char *offline_root_pre_script_cmd;
- char *offline_root_post_script_cmd;
+@@ -76,6 +76,7 @@ struct opkg_conf
+ int check_signature;
+ int nodeps; /* do not follow dependencies */
+ char *offline_root;
+ char *overlay_root;
int query_all;
int verbosity;
int noaction;
--- a/libopkg/opkg_install.c
+++ b/libopkg/opkg_install.c
-@@ -470,12 +470,15 @@
- * my diddling with the .opk file size below isn't going to cut it.
- * 3) return a proper error code instead of 1
- */
-- int comp_size, blocks_available;
-+ int comp_size, blocks_available = -1;
- char *root_dir;
-
- if (!conf->force_space && pkg->installed_size != NULL) {
- root_dir = pkg->dest ? pkg->dest->root_dir : conf->default_dest->root_dir;
-- blocks_available = get_available_blocks(root_dir);
-+ if (conf->overlay_root != NULL)
-+ blocks_available = get_available_blocks(conf->overlay_root);
-+ if (blocks_available < 0)
-+ blocks_available = get_available_blocks(root_dir);
+@@ -21,6 +21,7 @@
+ #include <time.h>
+ #include <signal.h>
+ #include <unistd.h>
++#include <sys/stat.h>
- comp_size = strtoul(pkg->installed_size, NULL, 0);
- /* round up a blocks count without doing fancy-but-slow casting jazz */
---- a/libopkg/opkg_utils.c
-+++ b/libopkg/opkg_utils.c
-@@ -31,10 +31,8 @@
+ #include "pkg.h"
+ #include "pkg_hash.h"
+@@ -189,13 +190,24 @@ static int
+ verify_pkg_installable(pkg_t *pkg)
{
- struct statfs sfs;
+ unsigned long kbs_available, pkg_size_kbs;
+- char *root_dir;
++ char *root_dir = NULL;
++ struct stat s;
-- if(statfs(filesystem, &sfs)){
-- fprintf(stderr, "bad statfs\n");
-- return 0;
-- }
-+ if(statfs(filesystem, &sfs))
-+ return -1;
- /* fprintf(stderr, "reported fs type %x\n", sfs.f_type); */
+ if (conf->force_space || pkg->installed_size == 0)
+ return 0;
- // Actually ((sfs.f_bavail * sfs.f_bsize) / 1024)
+- root_dir = pkg->dest ? pkg->dest->root_dir :
+- conf->default_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;
++
+ kbs_available = get_available_kbytes(root_dir);
+
+ pkg_size_kbs = (pkg->installed_size + 1023)/1024;