remote controller: Fix entrypoint interaction bugs

Signed-off-by: Kohei Tokunaga <ktokunaga.mail@gmail.com>

build/result.go

@@ -388,7 +388,7 @@ func populateProcessConfigFromResult(req *gateway.StartRequest, res *gateway.Res
 	} else if img != nil {
 		args = append(args, img.Config.Entrypoint...)
 	}
-	if cfg.Cmd != nil {
+	if !cfg.NoCmd {
 		args = append(args, cfg.Cmd...)
 	} else if img != nil {
 		args = append(args, img.Config.Cmd...)

commands/build.go

@@ -698,6 +698,7 @@ func (cfg *invokeConfig) needsMonitor(retErr error) bool {
 func parseInvokeConfig(invoke string) (cfg invokeConfig, err error) {
 	cfg.invokeFlag = invoke
 	cfg.Tty = true
+	cfg.NoCmd = true
 	switch invoke {
 	case "default", "debug-shell":
 		return cfg, nil
@@ -706,6 +707,7 @@ func parseInvokeConfig(invoke string) (cfg invokeConfig, err error) {
 		// TODO: make this configurable via flags or restorable from LLB.
 		// Discussion: https://github.com/docker/buildx/pull/1640#discussion_r1113295900
 		cfg.Cmd = []string{"/bin/sh"}
+		cfg.NoCmd = false
 		return cfg, nil
 	}
 
@@ -731,10 +733,12 @@ func parseInvokeConfig(invoke string) (cfg invokeConfig, err error) {
 		switch key {
 		case "args":
 			cfg.Cmd = append(cfg.Cmd, maybeJSONArray(value)...)
+			cfg.NoCmd = false
 		case "entrypoint":
 			cfg.Entrypoint = append(cfg.Entrypoint, maybeJSONArray(value)...)
 			if cfg.Cmd == nil {
 				cfg.Cmd = []string{}
+				cfg.NoCmd = false
 			}
 		case "env":
 			cfg.Env = append(cfg.Env, maybeJSONArray(value)...)

controller/pb/controller.proto

@@ -200,6 +200,7 @@ message InvokeConfig {
   bool Tty = 8;
   bool Rollback = 9; // Kill all process in the container and recreate it.
   bool Initial = 10; // Run container from the initial state of that stage (supported only on the failed step)
+  bool NoCmd = 11; // Do not set cmd but use the image's default
 }
 
 message FdMessage {

monitor/commands/exec.go

@@ -41,6 +41,7 @@ func (cm *ExecCmd) Exec(ctx context.Context, args []string) error {
 	cfg := controllerapi.InvokeConfig{
 		Entrypoint: []string{args[1]},
 		Cmd:        args[2:],
+		NoCmd:      false,
 		// TODO: support other options as well via flags
 		Env:  cm.invokeConfig.Env,
 		User: cm.invokeConfig.User,

monitor/commands/rollback.go

@@ -47,6 +47,7 @@ func (cm *RollbackCmd) Exec(ctx context.Context, args []string) error {
 		if len(cmds) > 0 {
 			cfg.Entrypoint = []string{cmds[0]}
 			cfg.Cmd = cmds[1:]
+			cfg.NoCmd = false
 		}
 	}
 	id := cm.m.Rollback(ctx, cfg)

monitor/monitor.go

@@ -283,6 +283,7 @@ func (m *monitor) startInvoke(ctx context.Context, pid string, cfg controllerapi
 	if len(cfg.Entrypoint) == 0 && len(cfg.Cmd) == 0 {
 		cfg.Entrypoint = []string{"sh"} // launch shell by default
 		cfg.Cmd = []string{}
+		cfg.NoCmd = false
 	}
 	go func() {
 		// Start a new invoke