[cmdline] Generate command option help text automatically

Generate the command option help text automatically from the list of
defined options.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/arch/i386/hci/commands/pxe_cmd.c

 
 /** "stoppxe" command descriptor */
 static struct command_descriptor stoppxe_cmd =
-	COMMAND_DESC ( struct stoppxe_options, stoppxe_opts, 0, 0, "" );
+	COMMAND_DESC ( struct stoppxe_options, stoppxe_opts, 0, 0, NULL );
 
 /**
  * The "stoppxe" command

src/arch/x86/hci/commands/cpuid_cmd.c

 
 /** "cpuid" command descriptor */
 static struct command_descriptor cpuid_cmd =
-	COMMAND_DESC ( struct cpuid_options, cpuid_opts, 1, 1,
-		       "[--ext] [--ecx] <bit>" );
+	COMMAND_DESC ( struct cpuid_options, cpuid_opts, 1, 1, "<bit>" );
 
 /**
  * The "cpuid" command

src/core/exec.c

 /** "echo" command descriptor */
 static struct command_descriptor echo_cmd =
 	COMMAND_DESC ( struct echo_options, echo_opts, 0, MAX_ARGUMENTS,
-		       "[-n] [...]" );
+		       "[...]" );
 
 /**
  * "echo" command

src/core/parseopt.c

  * @v argv		Argument list
  */
 void print_usage ( struct command_descriptor *cmd, char **argv ) {
-	printf ( "Usage:\n\n  %s %s\n\nSee http://ipxe.org/cmd/%s for further "
-		 "information\n", argv[0], cmd->usage, argv[0] );
+	struct option_descriptor *option;
+	unsigned int i;
+	int is_optional;
+
+	printf ( "Usage:\n\n  %s", argv[0] );
+	for ( i = 0 ; i < cmd->num_options ; i++ ) {
+		option = &cmd->options[i];
+		printf ( " [-%c|--%s", option->shortopt, option->longopt );
+		if ( option->has_arg ) {
+			is_optional = ( option->has_arg == optional_argument );
+			printf ( " %s<%s>%s", ( is_optional ? "[" : "" ),
+				 option->longopt, ( is_optional ? "]" : "" ) );
+		}
+		printf ( "]" );
+	}
+	if ( cmd->usage )
+		printf ( " %s", cmd->usage );
+	printf ( "\n\nSee http://ipxe.org/cmd/%s for further information\n",
+		 argv[0] );
 }
 
 /**

src/hci/commands/fcmgmt_cmd.c

 
 /** "fcstat" command descriptor */
 static struct command_descriptor fcstat_cmd =
-	COMMAND_DESC ( struct fcstat_options, fcstat_opts, 0, 0, "" );
+	COMMAND_DESC ( struct fcstat_options, fcstat_opts, 0, 0, NULL );
 
 /**
  * The "fcstat" command
 
 /** "fcels" command descriptor */
 static struct command_descriptor fcels_cmd =
-	COMMAND_DESC ( struct fcels_options, fcels_opts, 1, 1,
-		       "[--port <port>] [--id <peer port id>] <request>" );
+	COMMAND_DESC ( struct fcels_options, fcels_opts, 1, 1, "<request>" );
 
 /**
  * The "fcels" command

src/hci/commands/ifmgmt_cmd.c

 /** "ifconf" command descriptor */
 static struct ifcommon_command_descriptor ifconf_cmd =
 	IFCOMMON_COMMAND_DESC ( struct ifconf_options, ifconf_opts,
-				0, MAX_ARGUMENTS,
-				"[--configurator <configurator>] "
-				"[<interface>...]",
+				0, MAX_ARGUMENTS, "[<interface>...]",
 				ifconf_payload, 1 );
 
 /**

src/hci/commands/image_cmd.c

 };
 
 /** "img{single}" option list */
-static struct option_descriptor imgsingle_opts[] = {
-	OPTION_DESC ( "name", 'n', required_argument,
-		      struct imgsingle_options, name, parse_string ),
-	OPTION_DESC ( "replace", 'r', no_argument,
-		      struct imgsingle_options, replace, parse_flag ),
-	OPTION_DESC ( "autofree", 'a', no_argument,
-		      struct imgsingle_options, autofree, parse_flag ),
+static union {
+	/* "imgexec" takes all three options */
+	struct option_descriptor imgexec[3];
+	/* Other "img{single}" commands take only --name and --autofree */
+	struct option_descriptor imgsingle[2];
+} opts = {
+	.imgexec = {
+		OPTION_DESC ( "name", 'n', required_argument,
+			      struct imgsingle_options, name, parse_string ),
+		OPTION_DESC ( "autofree", 'a', no_argument,
+			      struct imgsingle_options, autofree, parse_flag ),
+		OPTION_DESC ( "replace", 'r', no_argument,
+			      struct imgsingle_options, replace, parse_flag ),
+	},
 };
 
-/** "img{single}" command descriptor */
-static struct command_descriptor imgsingle_cmd =
-	COMMAND_DESC ( struct imgsingle_options, imgsingle_opts,
-		       1, MAX_ARGUMENTS,
-		       "[--name <name>] [--autofree] "
-		       "<uri|image> [<arguments>...]" );
-
 /** An "img{single}" family command descriptor */
 struct imgsingle_descriptor {
 	/** Command descriptor */
 
 /** "imgfetch" command descriptor */
 static struct command_descriptor imgfetch_cmd =
-	COMMAND_DESC ( struct imgsingle_options, imgsingle_opts,
-		       1, MAX_ARGUMENTS,
-		       "[--name <name>] [--autofree] <uri> [<arguments>...]" );
+	COMMAND_DESC ( struct imgsingle_options, opts.imgsingle,
+		       1, MAX_ARGUMENTS, "<uri> [<arguments>...]" );
 
 /** "imgfetch" family command descriptor */
 struct imgsingle_descriptor imgfetch_desc = {
 	return image_select ( image );
 }
 
+/** "imgselect" command descriptor */
+static struct command_descriptor imgselect_cmd =
+	COMMAND_DESC ( struct imgsingle_options, opts.imgsingle,
+		       1, MAX_ARGUMENTS, "<uri|image> [<arguments>...]" );
+
 /** "imgselect" family command descriptor */
 struct imgsingle_descriptor imgselect_desc = {
-	.cmd = &imgsingle_cmd,
+	.cmd = &imgselect_cmd,
 	.acquire = imgacquire,
 	.action = imgselect,
 	.verb = "select",
 
 /** "imgexec" command descriptor */
 static struct command_descriptor imgexec_cmd =
-	COMMAND_DESC ( struct imgsingle_options, imgsingle_opts,
-		       0, MAX_ARGUMENTS,
-		       "[--autofree] [--replace] "
-		       "[<uri|image> [<arguments>...]]" );
+	COMMAND_DESC ( struct imgsingle_options, opts.imgexec,
+		       0, MAX_ARGUMENTS, "[<uri|image> [<arguments>...]]" );
 
 /**
  * "imgexec" command action
 	return imgsingle_exec ( argc, argv, &imgexec_desc );
 }
 
+/** "imgargs" command descriptor */
+static struct command_descriptor imgargs_cmd =
+	COMMAND_DESC ( struct imgsingle_options, opts.imgsingle,
+		       1, MAX_ARGUMENTS, "<uri|image> [<arguments>...]" );
+
 /** "imgargs" family command descriptor */
 struct imgsingle_descriptor imgargs_desc = {
-	.cmd = &imgsingle_cmd,
+	.cmd = &imgargs_cmd,
 	.acquire = imgacquire,
 	.preaction = image_clear_cmdline,
 };

src/hci/commands/image_trust_cmd.c

 
 /** "imgtrust" command descriptor */
 static struct command_descriptor imgtrust_cmd =
-	COMMAND_DESC ( struct imgtrust_options, imgtrust_opts, 0, 0,
-		       "[--allow] [--permanent]" );
+	COMMAND_DESC ( struct imgtrust_options, imgtrust_opts, 0, 0, NULL );
 
 /**
  * The "imgtrust" command
 /** "imgverify" command descriptor */
 static struct command_descriptor imgverify_cmd =
 	COMMAND_DESC ( struct imgverify_options, imgverify_opts, 2, 2,
-		       "[--signer <signer>] [--keep] <uri|image> "
-		       "<signature uri|image>" );
+		       "<uri|image> <signature uri|image>" );
 
 /**
  * The "imgverify" command

src/hci/commands/login_cmd.c

 
 /** "login" command descriptor */
 static struct command_descriptor login_cmd =
-	COMMAND_DESC ( struct login_options, login_opts, 0, 0, "" );
+	COMMAND_DESC ( struct login_options, login_opts, 0, 0, NULL );
 
 /**
  * "login" command

src/hci/commands/lotest_cmd.c

 /** "lotest" command descriptor */
 static struct command_descriptor lotest_cmd =
 	COMMAND_DESC ( struct lotest_options, lotest_opts, 2, 2,
-		       "[--mtu <mtu>] <sending interface> "
-		       "<receiving interface>" );
+		       "<sending interface> <receiving interface>" );
 
 /**
  * "lotest" command

src/hci/commands/menu_cmd.c

 /** "menu" command descriptor */
 static struct command_descriptor menu_cmd =
 	COMMAND_DESC ( struct menu_options, menu_opts, 0, MAX_ARGUMENTS,
-		       "[--name <name>] [--delete] [<title>]" );
+		       "[<title>]" );
 
 /**
  * The "menu" command
 /** "item" command descriptor */
 static struct command_descriptor item_cmd =
 	COMMAND_DESC ( struct item_options, item_opts, 0, MAX_ARGUMENTS,
-		       "[--menu <menu>] [--key <key>] [--default] "
-		       "[<label>|--gap [<text>]]" );
+		       "[<label> [<text>]]" );
 
 /**
  * The "item" command
 
 /** "choose" command descriptor */
 static struct command_descriptor choose_cmd =
-	COMMAND_DESC ( struct choose_options, choose_opts, 1, 1,
-		       "[--menu <menu>] [--default <label>] "
-		       "[--timeout <timeout>] [--keep] <setting>" );
+	COMMAND_DESC ( struct choose_options, choose_opts, 1, 1, "<setting>" );
 
 /**
  * The "choose" command

src/hci/commands/neighbour_cmd.c

 
 /** "nstat" command descriptor */
 static struct command_descriptor nstat_cmd =
-	COMMAND_DESC ( struct nstat_options, nstat_opts, 0, 0, "" );
+	COMMAND_DESC ( struct nstat_options, nstat_opts, 0, 0, NULL );
 
 /**
  * The "nstat" command

src/hci/commands/param_cmd.c

 
 /** "params" command descriptor */
 static struct command_descriptor params_cmd =
-	COMMAND_DESC ( struct params_options, params_opts, 0, 0,
-		       "[--name <name>] [--delete]" );
+	COMMAND_DESC ( struct params_options, params_opts, 0, 0, NULL );
 
 /**
  * The "params" command
 /** "param" command descriptor */
 static struct command_descriptor param_cmd =
 	COMMAND_DESC ( struct param_options, param_opts, 1, MAX_ARGUMENTS,
-		       "[--params <params>] <key> [<value>]" );
+		       "<key> [<value>]" );
 
 /**
  * The "param" command

src/hci/commands/ping_cmd.c

 
 /** "ping" command descriptor */
 static struct command_descriptor ping_cmd =
-	COMMAND_DESC ( struct ping_options, ping_opts, 1, 1,
-		       "[--size <size>] [--timeout <timeout>] <host>" );
+	COMMAND_DESC ( struct ping_options, ping_opts, 1, 1, "<host>" );
 
 /**
  * The "ping" command

src/hci/commands/poweroff_cmd.c

 
 /** "poweroff" command descriptor */
 static struct command_descriptor poweroff_cmd =
-	COMMAND_DESC ( struct poweroff_options, poweroff_opts, 0, 0, "" );
+	COMMAND_DESC ( struct poweroff_options, poweroff_opts, 0, 0, NULL );
 
 /**
  * The "poweroff" command

src/hci/commands/reboot_cmd.c

 
 /** "reboot" command descriptor */
 static struct command_descriptor reboot_cmd =
-	COMMAND_DESC ( struct reboot_options, reboot_opts, 0, 0, "[--warm]" );
+	COMMAND_DESC ( struct reboot_options, reboot_opts, 0, 0, NULL );
 
 /**
  * The "reboot" command

src/hci/commands/route_cmd.c

 
 /** "route" command descriptor */
 static struct command_descriptor route_cmd =
-	COMMAND_DESC ( struct route_options, route_opts, 0, 0, "" );
+	COMMAND_DESC ( struct route_options, route_opts, 0, 0, NULL );
 
 /**
  * The "route" command

src/hci/commands/sanboot_cmd.c

 };
 
 /** "sanboot" option list */
-static struct option_descriptor sanboot_opts[] = {
-	OPTION_DESC ( "drive", 'd', required_argument,
-		      struct sanboot_options, drive, parse_integer ),
-	OPTION_DESC ( "no-describe", 'n', no_argument,
-		      struct sanboot_options, no_describe, parse_flag ),
-	OPTION_DESC ( "keep", 'k', no_argument,
-		      struct sanboot_options, keep, parse_flag ),
+static union {
+	/* "sanboot" takes all three options */
+	struct option_descriptor sanboot[3];
+	/* "sanhook" takes only --drive and --no-describe */
+	struct option_descriptor sanhook[2];
+	/* "sanunhook" takes only --drive */
+	struct option_descriptor sanunhook[1];
+} opts = {
+	.sanboot = {
+		OPTION_DESC ( "drive", 'd', required_argument,
+			      struct sanboot_options, drive, parse_integer ),
+		OPTION_DESC ( "no-describe", 'n', no_argument,
+			      struct sanboot_options, no_describe, parse_flag ),
+		OPTION_DESC ( "keep", 'k', no_argument,
+			      struct sanboot_options, keep, parse_flag ),
+	},
 };
 
+
 /** "sanhook" command descriptor */
 static struct command_descriptor sanhook_cmd =
-	COMMAND_DESC ( struct sanboot_options, sanboot_opts, 1, 1,
-		       "[--drive <drive>] [--no-describe] <root-path>" );
+	COMMAND_DESC ( struct sanboot_options, opts.sanhook, 1, 1,
+		       "<root-path>" );
 
 /** "sanboot" command descriptor */
 static struct command_descriptor sanboot_cmd =
-	COMMAND_DESC ( struct sanboot_options, sanboot_opts, 0, 1,
-		       "[--drive <drive>] [--no-describe] [--keep] "
+	COMMAND_DESC ( struct sanboot_options, opts.sanboot, 0, 1,
 		       "[<root-path>]" );
 
 /** "sanunhook" command descriptor */
 static struct command_descriptor sanunhook_cmd =
-	COMMAND_DESC ( struct sanboot_options, sanboot_opts, 0, 0,
-		       "[--drive <drive>]" );
+	COMMAND_DESC ( struct sanboot_options, opts.sanunhook, 0, 0, NULL );
 
 /**
  * The "sanboot", "sanhook" and "sanunhook" commands

src/hci/commands/sync_cmd.c

 
 /** "sync" command descriptor */
 static struct command_descriptor sync_cmd =
-	COMMAND_DESC ( struct sync_options, sync_opts, 0, 0,
-		       "[--timeout <timeout>]" );
+	COMMAND_DESC ( struct sync_options, sync_opts, 0, 0, NULL );
 
 /**
  * "sync" command

src/hci/commands/vlan_cmd.c

 /** "vcreate" command descriptor */
 static struct command_descriptor vcreate_cmd =
 	COMMAND_DESC ( struct vcreate_options, vcreate_opts, 1, 1,
-		       "--tag <tag> [--priority <priority>] "
 		       "<trunk interface>" );
 
 /**

src/hci/shell.c

 
 /** "shell" command descriptor */
 static struct command_descriptor shell_cmd =
-	COMMAND_DESC ( struct shell_options, shell_opts, 0, 0, "" );
+	COMMAND_DESC ( struct shell_options, shell_opts, 0, 0, NULL );
 
 /**
  * "shell" command

src/image/script.c

 /** "prompt" command descriptor */
 static struct command_descriptor prompt_cmd =
 	COMMAND_DESC ( struct prompt_options, prompt_opts, 0, MAX_ARGUMENTS,
-		       "[--key <key>] [--timeout <timeout>] [<text>]" );
+		       "[<text>]" );
 
 /**
  * "prompt" command