Switch to github.com/golang/dep for vendoring

Signed-off-by: Mrunal Patel <mrunalp@gmail.com>

vendor/github.com/containers/storage/pkg/plugins/discovery.go

@@ -0,0 +1,132 @@
+package plugins
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"net/url"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+)
+
+var (
+	// ErrNotFound plugin not found
+	ErrNotFound = errors.New("plugin not found")
+	socketsPath = "/run/oci-storage/plugins"
+	specsPaths  = []string{"/etc/oci-storage/plugins", "/usr/lib/oci-storage/plugins"}
+)
+
+// localRegistry defines a registry that is local (using unix socket).
+type localRegistry struct{}
+
+func newLocalRegistry() localRegistry {
+	return localRegistry{}
+}
+
+// Scan scans all the plugin paths and returns all the names it found
+func Scan() ([]string, error) {
+	var names []string
+	if err := filepath.Walk(socketsPath, func(path string, fi os.FileInfo, err error) error {
+		if err != nil {
+			return nil
+		}
+
+		if fi.Mode()&os.ModeSocket != 0 {
+			name := strings.TrimSuffix(fi.Name(), filepath.Ext(fi.Name()))
+			names = append(names, name)
+		}
+		return nil
+	}); err != nil {
+		return nil, err
+	}
+
+	for _, path := range specsPaths {
+		if err := filepath.Walk(path, func(p string, fi os.FileInfo, err error) error {
+			if err != nil || fi.IsDir() {
+				return nil
+			}
+			name := strings.TrimSuffix(fi.Name(), filepath.Ext(fi.Name()))
+			names = append(names, name)
+			return nil
+		}); err != nil {
+			return nil, err
+		}
+	}
+	return names, nil
+}
+
+// Plugin returns the plugin registered with the given name (or returns an error).
+func (l *localRegistry) Plugin(name string) (*Plugin, error) {
+	socketpaths := pluginPaths(socketsPath, name, ".sock")
+
+	for _, p := range socketpaths {
+		if fi, err := os.Stat(p); err == nil && fi.Mode()&os.ModeSocket != 0 {
+			return NewLocalPlugin(name, "unix://"+p), nil
+		}
+	}
+
+	var txtspecpaths []string
+	for _, p := range specsPaths {
+		txtspecpaths = append(txtspecpaths, pluginPaths(p, name, ".spec")...)
+		txtspecpaths = append(txtspecpaths, pluginPaths(p, name, ".json")...)
+	}
+
+	for _, p := range txtspecpaths {
+		if _, err := os.Stat(p); err == nil {
+			if strings.HasSuffix(p, ".json") {
+				return readPluginJSONInfo(name, p)
+			}
+			return readPluginInfo(name, p)
+		}
+	}
+	return nil, ErrNotFound
+}
+
+func readPluginInfo(name, path string) (*Plugin, error) {
+	content, err := ioutil.ReadFile(path)
+	if err != nil {
+		return nil, err
+	}
+	addr := strings.TrimSpace(string(content))
+
+	u, err := url.Parse(addr)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(u.Scheme) == 0 {
+		return nil, fmt.Errorf("Unknown protocol")
+	}
+
+	return NewLocalPlugin(name, addr), nil
+}
+
+func readPluginJSONInfo(name, path string) (*Plugin, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	var p Plugin
+	if err := json.NewDecoder(f).Decode(&p); err != nil {
+		return nil, err
+	}
+	p.name = name
+	if len(p.TLSConfig.CAFile) == 0 {
+		p.TLSConfig.InsecureSkipVerify = true
+	}
+	p.activateWait = sync.NewCond(&sync.Mutex{})
+
+	return &p, nil
+}
+
+func pluginPaths(base, name, ext string) []string {
+	return []string{
+		filepath.Join(base, name+ext),
+		filepath.Join(base, name, name+ext),
+	}
+}