posix: shell: introduce top level posix command

Added a top level `posix` shell command for other POSIX
commands. Currently only `uname` is supported.

New POSIX commands can be added by including the
`posix_shell.h` header and use the `POSIX_CMD_ADD` helper
macro.

Signed-off-by: Yong Cong Sin <[email protected]>

Author: ycsin

lib/posix/shell/CMakeLists.txt

@@ -1,4 +1,5 @@
 # Copyright (c) 2024 Meta
 # SPDX-License-Identifier: Apache-2.0
 
+zephyr_library_sources_ifdef(CONFIG_POSIX_SHELL posix_shell.c)
 zephyr_library_sources_ifdef(CONFIG_POSIX_UNAME_SHELL uname.c)

lib/posix/shell/Kconfig

@@ -3,6 +3,11 @@
 
 if SHELL
 
+config POSIX_SHELL
+	bool
+	help
+	  Compile the parent `posix` shell command.
+
 rsource "Kconfig.uname"
 
 endif # SHELL

lib/posix/shell/Kconfig.uname

@@ -6,6 +6,7 @@ if POSIX_UNAME
 config POSIX_UNAME_SHELL
 	bool "Support for `uname` command"
 	select SHELL_GETOPT
+	select POSIX_SHELL
 	help
 	  Support for `uname` command in the terminal.
 

lib/posix/shell/posix_shell.c

@@ -0,0 +1,10 @@
+/*
+ * Copyright (c) 2024 Meta
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/shell/shell.h>
+
+SHELL_SUBCMD_SET_CREATE(posix_cmds, (posix));
+SHELL_CMD_ARG_REGISTER(posix, &posix_cmds, "POSIX shell commands", NULL, 2, 0);

lib/posix/shell/posix_shell.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024 Meta
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef ZEPHYR_LIB_POSIX_SHELL_POSIX_SHELL_H_
+#define ZEPHYR_LIB_POSIX_SHELL_POSIX_SHELL_H_
+
+#include <zephyr/shell/shell.h>
+
+/* Add command to the set of POSIX subcommands, see `SHELL_SUBCMD_ADD` */
+#define POSIX_CMD_ADD(_syntax, _subcmd, _help, _handler, _mand, _opt)                              \
+	SHELL_SUBCMD_ADD((posix), _syntax, _subcmd, _help, _handler, _mand, _opt);
+
+#endif /* ZEPHYR_LIB_POSIX_SHELL_POSIX_SHELL_H_ */

lib/posix/shell/uname.c

@@ -6,6 +6,8 @@
 
 #include <unistd.h>
 
+#include "posix_shell.h"
+
 #include <zephyr/posix/sys/utsname.h>
 #include <zephyr/shell/shell.h>
 
@@ -168,4 +170,4 @@ static int uname_cmd_handler(const struct shell *sh, size_t argc, char **argv)
 	return 0;
 }
 
-SHELL_CMD_REGISTER(uname, NULL, NULL, uname_cmd_handler);
+POSIX_CMD_ADD(uname, NULL, "Print system information", uname_cmd_handler, 1, 1);