hst/config: handle filesystem entry targeting root

This allows any fstype supported by hst to be directly mounted on sysroot. A special case in internal/app applies the matching entry early and excludes it from path hiding.

Closes #5.

Signed-off-by: Ophestra <cat@gensokyo.uk>

hst/config.go

@@ -93,17 +93,12 @@ type (
 
 		// pass through all devices
 		Device bool `json:"device,omitempty"`
-		// container mount points
+		// container mount points;
+		// if the first element targets /, it is inserted early and excluded from path hiding
 		Filesystem []FilesystemConfigJSON `json:"filesystem"`
 		// create symlinks inside container filesystem
 		Link []LinkConfig `json:"symlink"`
 
-		// automatically bind mount top-level directories to container root;
-		// the zero value disables this behaviour
-		AutoRoot *container.Absolute `json:"auto_root,omitempty"`
-		// extra flags for AutoRoot
-		RootFlags int `json:"root_flags,omitempty"`
-
 		// read-only /etc directory
 		Etc *container.Absolute `json:"etc,omitempty"`
 		// automatically set up /etc symlinks

hst/hst.go

@@ -97,6 +97,7 @@ func Template() *Config {
 				"GOOGLE_DEFAULT_CLIENT_SECRET": "OTJgUOQcT7lO7GsGZq2G4IlT",
 			},
 			Filesystem: []FilesystemConfigJSON{
+				{&FSBind{container.AbsFHSRoot, container.AbsFHSVarLib.Append("hakurei/base/org.debian"), true, false, false, true}},
 				{&FSEphemeral{Target: container.AbsFHSTmp, Write: true, Perm: 0755}},
 				{&FSOverlay{
 					Target: container.MustAbs("/nix/store"),
@@ -111,11 +112,9 @@ func Template() *Config {
 					Target: container.MustAbs("/data/data/org.chromium.Chromium"), Write: true}},
 				{&FSBind{Source: container.AbsFHSDev.Append("dri"), Device: true, Optional: true}},
 			},
-			Link:      []LinkConfig{{container.AbsFHSRunUser.Append("65534"), container.FHSRunUser + "150"}},
-			AutoRoot:  container.AbsFHSVarLib.Append("hakurei/base/org.debian"),
-			RootFlags: container.BindWritable,
-			Etc:       container.AbsFHSEtc,
-			AutoEtc:   true,
+			Link:    []LinkConfig{{container.AbsFHSRunUser.Append("65534"), container.FHSRunUser + "150"}},
+			Etc:     container.AbsFHSEtc,
+			AutoEtc: true,
 		},
 	}
 }

hst/hst_test.go

@@ -102,6 +102,13 @@ func TestTemplate(t *testing.T) {
 		"map_real_uid": true,
 		"device": true,
 		"filesystem": [
+			{
+				"type": "bind",
+				"dst": "/",
+				"src": "/var/lib/hakurei/base/org.debian",
+				"write": true,
+				"autoroot": true
+			},
 			{
 				"type": "ephemeral",
 				"dst": "/tmp/",
@@ -148,8 +155,6 @@ func TestTemplate(t *testing.T) {
 				"linkname": "/run/user/150"
 			}
 		],
-		"auto_root": "/var/lib/hakurei/base/org.debian",
-		"root_flags": 2,
 		"etc": "/etc/",
 		"auto_etc": true
 	}