added shell command input to commands prepending shell

pkg/commands/cmd.go

@@ -35,8 +35,13 @@ func (c *CmdCommand) ExecuteCommand(config *v1.Config) error {
 	var newCommand []string
 	if c.cmd.PrependShell {
 		// This is the default shell on Linux
-		// TODO: Support shell command here
-		shell := []string{"/bin/sh", "-c"}
+		var shell []string
+		if len(config.Shell) > 0 {
+			shell = config.Shell
+		} else {
+			shell = append(shell, "/bin/sh", "-c")
+		}
+
 		newCommand = append(shell, strings.Join(c.cmd.CmdLine, " "))
 	} else {
 		newCommand = c.cmd.CmdLine

pkg/commands/entrypoint.go

@@ -34,8 +34,13 @@ func (e *EntrypointCommand) ExecuteCommand(config *v1.Config) error {
 	var newCommand []string
 	if e.cmd.PrependShell {
 		// This is the default shell on Linux
-		// TODO: Support shell command here
-		shell := []string{"/bin/sh", "-c"}
+		var shell []string
+		if len(config.Shell) > 0 {
+			shell = config.Shell
+		} else {
+			shell = append(shell, "/bin/sh", "-c")
+		}
+
 		newCommand = append(shell, strings.Join(e.cmd.CmdLine, " "))
 	} else {
 		newCommand = e.cmd.CmdLine

pkg/commands/run.go

@@ -36,8 +36,13 @@ func (r *RunCommand) ExecuteCommand(config *v1.Config) error {
 	var newCommand []string
 	if r.cmd.PrependShell {
 		// This is the default shell on Linux
-		// TODO: Support shell command here
-		shell := []string{"/bin/sh", "-c"}
+		var shell []string
+		if len(config.Shell) > 0 {
+			shell = config.Shell
+		} else {
+			shell = append(shell, "/bin/sh", "-c")
+		}
+
 		newCommand = append(shell, strings.Join(r.cmd.CmdLine, " "))
 	} else {
 		newCommand = r.cmd.CmdLine