kiss: Added package conflicts.

kiss

@@ -134,15 +134,41 @@ pkg_tar() {
     log "Use '$kiss install $name' to install the package."
 }
 
+pkg_conflicts() {
+    log "Checking for package conflicts."
+
+    # Extract manifest from tarball and strip directories.
+    tar xf "$bin_dir/$pkg" "./var/db/$kiss/$name/manifest" -O |
+        while read -r line; do
+            [ -f "$line" ] && printf '%s\n' "$line" >> "$cac_dir/manifest"
+        done
+
+    # Compare extracted manifest to all installed manifests.
+    # If there are matching lines (files) there's a package
+    # conflict.
+    for db in "$sys_db"/*; do
+        [ "$name" = "${db##*/}" ] && continue
+
+        grep -Fxf "$cac_dir/manifest" "$db/manifest" &&
+            die "Package '$name' conflicts with '${db##*/}'."
+    done
+
+    rm "$cac_dir/manifest"
+}
+
 pkg_install() {
     [ -f "$bin_dir/$pkg" ] || args b "$name"
 
+    pkg_conflicts
+
     # Create a backup of 'tar' so it isn't removed during
     # package installation.
     cp "$(command -v tar)" "$cac_dir"
 
+    log "Removing previous version of package if it exists."
     pkg_remove "$name"
-    "$cac_dir/tar" kpxvf "$bin_dir/$pkg" -C "$sys_dir/"
+
+    "$cac_dir/tar" kpxf "$bin_dir/$pkg" -C "$sys_dir/"
     rm "$cac_dir/tar"
 
     "$sys_db/$name/post-install" 2>/dev/null