rework system connection and farm storage

We now no longer write containers.conf, instead system connections and
farms are written to a new file called podman-connections.conf.

This is a major rework and I had to change a lot of things to get this
to compile again with my c/common changes.

It is a breaking change for users as connections/farms added before this
commit can now no longer be removed or modified directly. However because
the logic keeps reading from containers.conf the old connections can
still be used to connect to a remote host.

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

vendor/github.com/containers/common/pkg/manifests/manifests.go

@@ -19,6 +19,7 @@ type List interface {
 	Remove(instanceDigest digest.Digest) error
 	SetURLs(instanceDigest digest.Digest, urls []string) error
 	URLs(instanceDigest digest.Digest) ([]string, error)
+	ClearAnnotations(instanceDigest *digest.Digest) error
 	SetAnnotations(instanceDigest *digest.Digest, annotations map[string]string) error
 	Annotations(instanceDigest *digest.Digest) (map[string]string, error)
 	SetOS(instanceDigest digest.Digest, os string) error
@@ -100,18 +101,21 @@ func (l *list) AddInstance(manifestDigest digest.Digest, manifestSize int64, man
 		Platform: schema2platform,
 	})
 
-	ociv1platform := v1.Platform{
+	ociv1platform := &v1.Platform{
 		Architecture: architecture,
 		OS:           osName,
 		OSVersion:    osVersion,
 		OSFeatures:   osFeatures,
 		Variant:      variant,
 	}
+	if ociv1platform.Architecture == "" && ociv1platform.OS == "" && ociv1platform.OSVersion == "" && ociv1platform.Variant == "" && len(ociv1platform.OSFeatures) == 0 {
+		ociv1platform = nil
+	}
 	l.oci.Manifests = append(l.oci.Manifests, v1.Descriptor{
 		MediaType: manifestType,
 		Size:      manifestSize,
 		Digest:    manifestDigest,
-		Platform:  &ociv1platform,
+		Platform:  ociv1platform,
 	})
 
 	return nil
@@ -170,7 +174,13 @@ func (l *list) SetURLs(instanceDigest digest.Digest, urls []string) error {
 		return err
 	}
 	oci.URLs = append([]string{}, urls...)
+	if len(oci.URLs) == 0 {
+		oci.URLs = nil
+	}
 	docker.URLs = append([]string{}, urls...)
+	if len(docker.URLs) == 0 {
+		docker.URLs = nil
+	}
 	return nil
 }
 
@@ -183,7 +193,24 @@ func (l *list) URLs(instanceDigest digest.Digest) ([]string, error) {
 	return append([]string{}, oci.URLs...), nil
 }
 
-// SetAnnotations sets annotations on the image index, or on a specific manifest.
+// ClearAnnotations removes all annotations from the image index, or from a
+// specific manifest.
+// The field is specific to the OCI image index format, and is not present in Docker manifest lists.
+func (l *list) ClearAnnotations(instanceDigest *digest.Digest) error {
+	a := &l.oci.Annotations
+	if instanceDigest != nil {
+		oci, err := l.findOCIv1(*instanceDigest)
+		if err != nil {
+			return err
+		}
+		a = &oci.Annotations
+	}
+	*a = nil
+	return nil
+}
+
+// SetAnnotations sets annotations on the image index, or on a specific
+// manifest.
 // The field is specific to the OCI image index format, and is not present in Docker manifest lists.
 func (l *list) SetAnnotations(instanceDigest *digest.Digest, annotations map[string]string) error {
 	a := &l.oci.Annotations
@@ -194,10 +221,15 @@ func (l *list) SetAnnotations(instanceDigest *digest.Digest, annotations map[str
 		}
 		a = &oci.Annotations
 	}
-	(*a) = make(map[string]string)
+	if *a == nil {
+		(*a) = make(map[string]string)
+	}
 	for k, v := range annotations {
 		(*a)[k] = v
 	}
+	if len(*a) == 0 {
+		*a = nil
+	}
 	return nil
 }
 
@@ -230,7 +262,13 @@ func (l *list) SetOS(instanceDigest digest.Digest, os string) error {
 		return err
 	}
 	docker.Platform.OS = os
+	if oci.Platform == nil {
+		oci.Platform = &v1.Platform{}
+	}
 	oci.Platform.OS = os
+	if oci.Platform.Architecture == "" && oci.Platform.OS == "" && oci.Platform.OSVersion == "" && oci.Platform.Variant == "" && len(oci.Platform.OSFeatures) == 0 {
+		oci.Platform = nil
+	}
 	return nil
 }
 
@@ -240,7 +278,11 @@ func (l *list) OS(instanceDigest digest.Digest) (string, error) {
 	if err != nil {
 		return "", err
 	}
-	return oci.Platform.OS, nil
+	platform := oci.Platform
+	if platform == nil {
+		platform = &v1.Platform{}
+	}
+	return platform.OS, nil
 }
 
 // SetArchitecture sets the Architecture field in the platform information associated with the instance with the specified digest.
@@ -254,7 +296,13 @@ func (l *list) SetArchitecture(instanceDigest digest.Digest, arch string) error
 		return err
 	}
 	docker.Platform.Architecture = arch
+	if oci.Platform == nil {
+		oci.Platform = &v1.Platform{}
+	}
 	oci.Platform.Architecture = arch
+	if oci.Platform.Architecture == "" && oci.Platform.OS == "" && oci.Platform.OSVersion == "" && oci.Platform.Variant == "" && len(oci.Platform.OSFeatures) == 0 {
+		oci.Platform = nil
+	}
 	return nil
 }
 
@@ -264,7 +312,11 @@ func (l *list) Architecture(instanceDigest digest.Digest) (string, error) {
 	if err != nil {
 		return "", err
 	}
-	return oci.Platform.Architecture, nil
+	platform := oci.Platform
+	if platform == nil {
+		platform = &v1.Platform{}
+	}
+	return platform.Architecture, nil
 }
 
 // SetOSVersion sets the OSVersion field in the platform information associated with the instance with the specified digest.
@@ -278,7 +330,13 @@ func (l *list) SetOSVersion(instanceDigest digest.Digest, osVersion string) erro
 		return err
 	}
 	docker.Platform.OSVersion = osVersion
+	if oci.Platform == nil {
+		oci.Platform = &v1.Platform{}
+	}
 	oci.Platform.OSVersion = osVersion
+	if oci.Platform.Architecture == "" && oci.Platform.OS == "" && oci.Platform.OSVersion == "" && oci.Platform.Variant == "" && len(oci.Platform.OSFeatures) == 0 {
+		oci.Platform = nil
+	}
 	return nil
 }
 
@@ -288,7 +346,11 @@ func (l *list) OSVersion(instanceDigest digest.Digest) (string, error) {
 	if err != nil {
 		return "", err
 	}
-	return oci.Platform.OSVersion, nil
+	platform := oci.Platform
+	if platform == nil {
+		platform = &v1.Platform{}
+	}
+	return platform.OSVersion, nil
 }
 
 // SetVariant sets the Variant field in the platform information associated with the instance with the specified digest.
@@ -302,7 +364,13 @@ func (l *list) SetVariant(instanceDigest digest.Digest, variant string) error {
 		return err
 	}
 	docker.Platform.Variant = variant
+	if oci.Platform == nil {
+		oci.Platform = &v1.Platform{}
+	}
 	oci.Platform.Variant = variant
+	if oci.Platform.Architecture == "" && oci.Platform.OS == "" && oci.Platform.OSVersion == "" && oci.Platform.Variant == "" && len(oci.Platform.OSFeatures) == 0 {
+		oci.Platform = nil
+	}
 	return nil
 }
 
@@ -312,7 +380,11 @@ func (l *list) Variant(instanceDigest digest.Digest) (string, error) {
 	if err != nil {
 		return "", err
 	}
-	return oci.Platform.Variant, nil
+	platform := oci.Platform
+	if platform == nil {
+		platform = &v1.Platform{}
+	}
+	return platform.Variant, nil
 }
 
 // SetFeatures sets the features list in the platform information associated with the instance with the specified digest.
@@ -323,6 +395,9 @@ func (l *list) SetFeatures(instanceDigest digest.Digest, features []string) erro
 		return err
 	}
 	docker.Platform.Features = append([]string{}, features...)
+	if len(docker.Platform.Features) == 0 {
+		docker.Platform.Features = nil
+	}
 	// no OCI equivalent
 	return nil
 }
@@ -348,7 +423,16 @@ func (l *list) SetOSFeatures(instanceDigest digest.Digest, osFeatures []string)
 		return err
 	}
 	docker.Platform.OSFeatures = append([]string{}, osFeatures...)
+	if oci.Platform == nil {
+		oci.Platform = &v1.Platform{}
+	}
 	oci.Platform.OSFeatures = append([]string{}, osFeatures...)
+	if len(oci.Platform.OSFeatures) == 0 {
+		oci.Platform.OSFeatures = nil
+	}
+	if oci.Platform.Architecture == "" && oci.Platform.OS == "" && oci.Platform.OSVersion == "" && oci.Platform.Variant == "" && len(oci.Platform.OSFeatures) == 0 {
+		oci.Platform = nil
+	}
 	return nil
 }
 
@@ -358,7 +442,11 @@ func (l *list) OSFeatures(instanceDigest digest.Digest) ([]string, error) {
 	if err != nil {
 		return nil, err
 	}
-	return append([]string{}, oci.Platform.OSFeatures...), nil
+	platform := oci.Platform
+	if platform == nil {
+		platform = &v1.Platform{}
+	}
+	return append([]string{}, platform.OSFeatures...), nil
 }
 
 // SetMediaType sets the MediaType field in the instance with the specified digest.