Add ability to prune containers and images

Allow user to prune unused/unnamed images, the layer images from building,
via podman rmi --prune.

Allow user to prune stopped/exiuted containers via podman rm --prune.

This should resolve #1910

Signed-off-by: baude <bbaude@redhat.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/libpod/image/prune.go b/libpod/image/prune.go
new file mode 100644
index 000000000..6a1f160d5
--- /dev/null
+++ b/libpod/image/prune.go
@@ -0,0 +1,26 @@
+package image
+
+// GetPruneImages returns a slice of images that have no names/unused
+func (ir *Runtime) GetPruneImages() ([]*Image, error) {
+	var (
+		unamedImages []*Image
+	)
+	allImages, err := ir.GetImages()
+	if err != nil {
+		return nil, err
+	}
+	for _, i := range allImages {
+		if len(i.Names()) == 0 {
+			unamedImages = append(unamedImages, i)
+			continue
+		}
+		containers, err := i.Containers()
+		if err != nil {
+			return nil, err
+		}
+		if len(containers) < 1 {
+			unamedImages = append(unamedImages, i)
+		}
+	}
+	return unamedImages, nil
+}