podman-remote.conf enablement

add the ability for the podman remote client to use a configuration file
which describes its connections. users can now define a connection the
configuration and then call it by name like:

podman-remote -c connection1

and the destination and user will be derived from the configuration
file.  if no -c is provided, we look for a connection in the
configuration file designated as 'default'.  If the configuration file
has only one connection, it will be deemed the 'default'.

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

vendor/github.com/BurntSushi/toml/encode.go

@@ -16,17 +16,17 @@ type tomlEncodeError struct{ error }
 
 var (
 	errArrayMixedElementTypes = errors.New(
-		"can't encode array with mixed element types")
+		"toml: cannot encode array with mixed element types")
 	errArrayNilElement = errors.New(
-		"can't encode array with nil element")
+		"toml: cannot encode array with nil element")
 	errNonString = errors.New(
-		"can't encode a map with non-string key type")
+		"toml: cannot encode a map with non-string key type")
 	errAnonNonStruct = errors.New(
-		"can't encode an anonymous field that is not a struct")
+		"toml: cannot encode an anonymous field that is not a struct")
 	errArrayNoTable = errors.New(
-		"TOML array element can't contain a table")
+		"toml: TOML array element cannot contain a table")
 	errNoKey = errors.New(
-		"top-level values must be a Go map or struct")
+		"toml: top-level values must be Go maps or structs")
 	errAnything = errors.New("") // used in testing
 )
 
@@ -148,7 +148,7 @@ func (enc *Encoder) encode(key Key, rv reflect.Value) {
 	case reflect.Struct:
 		enc.eTable(key, rv)
 	default:
-		panic(e("Unsupported type for key '%s': %s", key, k))
+		panic(e("unsupported type for key '%s': %s", key, k))
 	}
 }
 
@@ -160,7 +160,7 @@ func (enc *Encoder) eElement(rv reflect.Value) {
 		// Special case time.Time as a primitive. Has to come before
 		// TextMarshaler below because time.Time implements
 		// encoding.TextMarshaler, but we need to always use UTC.
-		enc.wf(v.In(time.FixedZone("UTC", 0)).Format("2006-01-02T15:04:05Z"))
+		enc.wf(v.UTC().Format("2006-01-02T15:04:05Z"))
 		return
 	case TextMarshaler:
 		// Special case. Use text marshaler if it's available for this value.
@@ -191,7 +191,7 @@ func (enc *Encoder) eElement(rv reflect.Value) {
 	case reflect.String:
 		enc.writeQuoted(rv.String())
 	default:
-		panic(e("Unexpected primitive type: %s", rv.Kind()))
+		panic(e("unexpected primitive type: %s", rv.Kind()))
 	}
 }
 
@@ -241,7 +241,7 @@ func (enc *Encoder) eArrayOfTables(key Key, rv reflect.Value) {
 func (enc *Encoder) eTable(key Key, rv reflect.Value) {
 	panicIfInvalidKey(key)
 	if len(key) == 1 {
-		// Output an extra new line between top-level tables.
+		// Output an extra newline between top-level tables.
 		// (The newline isn't written if nothing else has been written though.)
 		enc.newline()
 	}
@@ -315,10 +315,16 @@ func (enc *Encoder) eStruct(key Key, rv reflect.Value) {
 				t := f.Type
 				switch t.Kind() {
 				case reflect.Struct:
-					addFields(t, frv, f.Index)
-					continue
+					// Treat anonymous struct fields with
+					// tag names as though they are not
+					// anonymous, like encoding/json does.
+					if getOptions(f.Tag).name == "" {
+						addFields(t, frv, f.Index)
+						continue
+					}
 				case reflect.Ptr:
-					if t.Elem().Kind() == reflect.Struct {
+					if t.Elem().Kind() == reflect.Struct &&
+						getOptions(f.Tag).name == "" {
 						if !frv.IsNil() {
 							addFields(t.Elem(), frv.Elem(), f.Index)
 						}
@@ -347,17 +353,18 @@ func (enc *Encoder) eStruct(key Key, rv reflect.Value) {
 				continue
 			}
 
-			tag := sft.Tag.Get("toml")
-			if tag == "-" {
+			opts := getOptions(sft.Tag)
+			if opts.skip {
 				continue
 			}
-			keyName, opts := getOptions(tag)
-			if keyName == "" {
-				keyName = sft.Name
+			keyName := sft.Name
+			if opts.name != "" {
+				keyName = opts.name
 			}
-			if _, ok := opts["omitempty"]; ok && isEmpty(sf) {
+			if opts.omitempty && isEmpty(sf) {
 				continue
-			} else if _, ok := opts["omitzero"]; ok && isZero(sf) {
+			}
+			if opts.omitzero && isZero(sf) {
 				continue
 			}
 
@@ -392,9 +399,8 @@ func tomlTypeOfGo(rv reflect.Value) tomlType {
 	case reflect.Array, reflect.Slice:
 		if typeEqual(tomlHash, tomlArrayType(rv)) {
 			return tomlArrayHash
-		} else {
-			return tomlArray
 		}
+		return tomlArray
 	case reflect.Ptr, reflect.Interface:
 		return tomlTypeOfGo(rv.Elem())
 	case reflect.String:
@@ -451,17 +457,30 @@ func tomlArrayType(rv reflect.Value) tomlType {
 	return firstType
 }
 
-func getOptions(keyName string) (string, map[string]struct{}) {
-	opts := make(map[string]struct{})
-	ss := strings.Split(keyName, ",")
-	name := ss[0]
-	if len(ss) > 1 {
-		for _, opt := range ss {
-			opts[opt] = struct{}{}
+type tagOptions struct {
+	skip      bool // "-"
+	name      string
+	omitempty bool
+	omitzero  bool
+}
+
+func getOptions(tag reflect.StructTag) tagOptions {
+	t := tag.Get("toml")
+	if t == "-" {
+		return tagOptions{skip: true}
+	}
+	var opts tagOptions
+	parts := strings.Split(t, ",")
+	opts.name = parts[0]
+	for _, s := range parts[1:] {
+		switch s {
+		case "omitempty":
+			opts.omitempty = true
+		case "omitzero":
+			opts.omitzero = true
 		}
 	}
-
-	return name, opts
+	return opts
 }
 
 func isZero(rv reflect.Value) bool {