Rework pruning to report reclaimed space

This change adds code to report the reclaimed space after a prune.
Reclaimed space from volumes, images, and containers is recorded
during the prune call in a PruneReport struct. These structs are
collected into a slice during a system prune and processed afterwards
to calculate the total reclaimed space.

Closes #8658

Signed-off-by: Baron Lenardson <lenardson.baron@gmail.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/libpod/volume.go b/libpod/volume.go
index 0535bf4db..ed08d375f 100644
--- a/libpod/volume.go
+++ b/libpod/volume.go
@@ -1,6 +1,8 @@
 package libpod
 
 import (
+	"os"
+	"path/filepath"
 	"time"
 
 	"github.com/containers/podman/v2/libpod/define"
@@ -79,6 +81,18 @@ func (v *Volume) Name() string {
 	return v.config.Name
 }
 
+// Returns the size on disk of volume
+func (v *Volume) Size() (uint64, error) {
+	var size uint64
+	err := filepath.Walk(v.config.MountPoint, func(path string, info os.FileInfo, err error) error {
+		if err == nil && !info.IsDir() {
+			size += (uint64)(info.Size())
+		}
+		return err
+	})
+	return size, err
+}
+
 // Driver retrieves the volume's driver.
 func (v *Volume) Driver() string {
 	return v.config.Driver