[parseopt] Refer to online documentation for command help

The online documentation (e.g. http://ipxe.org/cmd/ifopen), though not
yet complete, is far more comprehensive than could be provided within
the iPXE binary.  Save around 200 bytes (compressed) by removing the
command descriptions from the interactive help, and instead referring
users directly to the web page describing the relevant command.

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

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

@@ -33,7 +33,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 /** "startpxe" command descriptor */
 static struct command_descriptor startpxe_cmd =
 	COMMAND_DESC ( struct ifcommon_options, ifcommon_opts, 0, MAX_ARGUMENTS,
-		       "[<interface>]", "" );
+		       "[<interface>]" );
 
 /**
  * "startpxe" payload
@@ -68,8 +68,7 @@ static struct option_descriptor stoppxe_opts[] = {};
 
 /** "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, "" );
 
 /**
  * The "stoppxe" command

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

@@ -36,7 +36,7 @@ static struct option_descriptor reboot_opts[] = {};
 
 /** "reboot" command descriptor */
 static struct command_descriptor reboot_cmd =
-	COMMAND_DESC ( struct reboot_options, reboot_opts, 0, 0, "", "" );
+	COMMAND_DESC ( struct reboot_options, reboot_opts, 0, 0, "" );
 
 /**
  * The "reboot" command

src/core/exec.c

@@ -298,8 +298,7 @@ static struct option_descriptor exit_opts[] = {};
 
 /** "exit" command descriptor */
 static struct command_descriptor exit_cmd =
-	COMMAND_DESC ( struct exit_options, exit_opts, 0, 1,
-		       "[<status>]", "" );
+	COMMAND_DESC ( struct exit_options, exit_opts, 0, 1, "[<status>]" );
 
 /**
  * "exit" command
@@ -344,7 +343,7 @@ static struct option_descriptor isset_opts[] = {};
 /** "isset" command descriptor */
 static struct command_descriptor isset_cmd =
 	COMMAND_DESC ( struct isset_options, isset_opts, 0, MAX_ARGUMENTS,
-		       "[...]", "" );
+		       "[...]" );
 
 /**
  * "isset" command

src/core/parseopt.c

@@ -132,7 +132,8 @@ int parse_image ( const char *text, struct image **image ) {
  * @v argv		Argument list
  */
 void print_usage ( struct command_descriptor *cmd, char **argv ) {
-	printf ( "Usage:\n\n  %s %s\n", argv[0], cmd->usage_description );
+	printf ( "Usage:\n\n  %s %s\n\nSee http://ipxe.org/cmd/%s for further "
+		 "information\n", argv[0], cmd->usage, argv[0] );
 }
 
 /**

src/hci/commands/autoboot_cmd.c

@@ -35,7 +35,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 /** "autoboot" command descriptor */
 static struct command_descriptor autoboot_cmd =
 	COMMAND_DESC ( struct ifcommon_options, ifcommon_opts, 0, MAX_ARGUMENTS,
-		       "[<interface>...]", "Attempt to boot the system" );
+		       "[<interface>...]" );
 
 /**
  * "autoboot" command

src/hci/commands/config_cmd.c

@@ -41,9 +41,7 @@ static struct option_descriptor config_opts[] = {};
 
 /** "config" command descriptor */
 static struct command_descriptor config_cmd =
-	COMMAND_DESC ( struct config_options, config_opts, 0, 1,
-		       "[<scope>]",
-		       "Open the option configuration console" );
+	COMMAND_DESC ( struct config_options, config_opts, 0, 1, "[<scope>]" );
 
 /**
  * Parse settings scope name

src/hci/commands/dhcp_cmd.c

@@ -43,8 +43,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 /** "dhcp" command descriptor */
 static struct command_descriptor dhcp_cmd =
 	COMMAND_DESC ( struct ifcommon_options, ifcommon_opts, 0, MAX_ARGUMENTS,
-		       "[<interface>] [<interface>...]",
-		       "Configure network interface(s) using DHCP" );
+		       "[<interface>...]" );
 
 /**
  * Execute "dhcp" command for a network device
@@ -88,8 +87,7 @@ static struct option_descriptor pxebs_opts[] = {};
 /** "pxebs" command descriptor */
 static struct command_descriptor pxebs_cmd =
 	COMMAND_DESC ( struct pxebs_options, pxebs_opts, 2, 2,
-		       "<interface> <server_type>",
-		       "Perform PXE Boot Server discovery" );
+		       "<interface> <server type>" );
 
 /**
  * The "pxebs" command

src/hci/commands/digest_cmd.c

@@ -44,8 +44,7 @@ static struct option_descriptor digest_opts[] = {};
 /** "digest" command descriptor */
 static struct command_descriptor digest_cmd =
 	COMMAND_DESC ( struct digest_options, digest_opts, 1, MAX_ARGUMENTS,
-		       "<image> [<image>...]",
-		       "Calculate the digest of an image" );
+		       "<image> [<image>...]" );
 
 /**
  * The "digest" command

src/hci/commands/fcmgmt_cmd.c

@@ -106,8 +106,7 @@ static struct option_descriptor fcstat_opts[] = {};
 
 /** "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, "" );
 
 /**
  * The "fcstat" command
@@ -153,7 +152,7 @@ static struct option_descriptor fcels_opts[] = {
 /** "fcels" command descriptor */
 static struct command_descriptor fcels_cmd =
 	COMMAND_DESC ( struct fcels_options, fcels_opts, 1, 1,
-		       "[--port <port>] [--id <peer_port_id>] <command>", "" );
+		       "[--port <port>] [--id <peer port id>] <request>" );
 
 /**
  * The "fcels" command

src/hci/commands/gdbstub_cmd.c

@@ -65,12 +65,7 @@ static struct option_descriptor gdbstub_opts[] = {};
 /** "gdbstub" command descriptor */
 static struct command_descriptor gdbstub_cmd =
 	COMMAND_DESC ( struct gdbstub_options, gdbstub_opts, 1, MAX_ARGUMENTS,
-		       "<transport> [<options>...]",
-		       "Start remote debugging using one of the following "
-		       "transports:\n"
-		       "  serial           use serial port (if compiled in)\n"
-		       "  udp <interface>  use UDP over network interface "
-		       "(if compiled in)" );
+		       "<transport> [<options>...]" );
 
 /**
  * The "gdbstub" command

src/hci/commands/ifmgmt_cmd.c

@@ -87,8 +87,7 @@ int ifcommon_exec ( int argc, char **argv,
 /** "ifopen" command descriptor */
 static struct command_descriptor ifopen_cmd =
 	COMMAND_DESC ( struct ifcommon_options, ifcommon_opts, 0, MAX_ARGUMENTS,
-		       "[<interface>...]",
-		       "Open network interface(s)" );
+		       "[<interface>...]" );
 
 /**
  * "ifopen" payload
@@ -114,8 +113,7 @@ static int ifopen_exec ( int argc, char **argv ) {
 /** "ifclose" command descriptor */
 static struct command_descriptor ifclose_cmd =
 	COMMAND_DESC ( struct ifcommon_options, ifcommon_opts, 0, MAX_ARGUMENTS,
-		       "[<interface>...]",
-		       "Close network interface(s)" );
+		       "[<interface>...]" );
 
 /**
  * "ifclose" payload
@@ -142,8 +140,7 @@ static int ifclose_exec ( int argc, char **argv ) {
 /** "ifstat" command descriptor */
 static struct command_descriptor ifstat_cmd =
 	COMMAND_DESC ( struct ifcommon_options, ifcommon_opts, 0, MAX_ARGUMENTS,
-		       "[<interface>...]",
-		       "Show network interface(s)" );
+		       "[<interface>...]" );
 
 /**
  * "ifstat" payload

src/hci/commands/image_cmd.c

@@ -84,20 +84,17 @@ static struct option_descriptor imgfetch_opts[] = {
 /** "imgfetch" command descriptor */
 static struct command_descriptor imgfetch_cmd =
 	COMMAND_DESC ( struct imgfetch_options, imgfetch_opts, 1, MAX_ARGUMENTS,
-		       "[--name <name>] <image_url> [<arguments>...]",
-		       "Fetch image" );
+		       "[--name <name>] <uri> [<arguments>...]" );
 
 /** "kernel" command descriptor */
 static struct command_descriptor kernel_cmd =
 	COMMAND_DESC ( struct imgfetch_options, imgfetch_opts, 1, MAX_ARGUMENTS,
-		       "[--name <name>] <image_url> [<arguments>...]",
-		       "Fetch and load image" );
+		       "[--name <name>] <uri> [<arguments>...]" );
 
 /** "chain" command descriptor */
 static struct command_descriptor chain_cmd =
 	COMMAND_DESC ( struct imgfetch_options, imgfetch_opts, 1, MAX_ARGUMENTS,
-		       "[--name <name>] <image_url> [<arguments>...]",
-		       "Fetch and execute image" );
+		       "[--name <name>] <uri> [<arguments>...]" );
 
 /**
  * The "imgfetch" and friends command body
@@ -200,8 +197,7 @@ static struct option_descriptor imgload_opts[] = {};
 
 /** "imgload" command descriptor */
 static struct command_descriptor imgload_cmd =
-	COMMAND_DESC ( struct imgload_options, imgload_opts, 1, 1,
-		       "<image>", "Load image" );
+	COMMAND_DESC ( struct imgload_options, imgload_opts, 1, 1, "<image>" );
 
 /**
  * The "imgload" command
@@ -242,8 +238,7 @@ static struct option_descriptor imgargs_opts[] = {};
 /** "imgargs" command descriptor */
 static struct command_descriptor imgargs_cmd =
 	COMMAND_DESC ( struct imgargs_options, imgargs_opts, 1, MAX_ARGUMENTS,
-		       "<image> [<arguments>...]",
-		       "Set arguments for image" );
+		       "<image> [<arguments>...]" );
 
 /**
  * The "imgargs" command body
@@ -282,7 +277,7 @@ static struct option_descriptor imgexec_opts[] = {};
 /** "imgexec" command descriptor */
 static struct command_descriptor imgexec_cmd =
 	COMMAND_DESC ( struct imgexec_options, imgexec_opts, 0, 1,
-		       "[<image>]", "Execute image" );
+		       "[<image>]" );
 
 /**
  * The "imgexec" command
@@ -330,8 +325,7 @@ static struct option_descriptor imgstat_opts[] = {};
 
 /** "imgstat" command descriptor */
 static struct command_descriptor imgstat_cmd =
-	COMMAND_DESC ( struct imgstat_options, imgstat_opts, 0, 0,
-		       "", "List images" );
+	COMMAND_DESC ( struct imgstat_options, imgstat_opts, 0, 0, "" );
 
 /**
  * The "imgstat" command
@@ -366,7 +360,7 @@ static struct option_descriptor imgfree_opts[] = {};
 /** "imgfree" command descriptor */
 static struct command_descriptor imgfree_cmd =
 	COMMAND_DESC ( struct imgfree_options, imgfree_opts, 0, 1,
-		       "[<image>]", "Free image(s)" );
+		       "[<image>]" );
 
 /**
  * The "imgfree" command

src/hci/commands/iwmgmt_cmd.c

@@ -34,8 +34,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 /** "iwstat" command descriptor */
 static struct command_descriptor iwstat_cmd =
 	COMMAND_DESC ( struct ifcommon_options, ifcommon_opts, 0, MAX_ARGUMENTS,
-		       "[<interface>...]",
-		       "Show wireless interface(s)" );
+		       "[<interface>...]" );
 
 /**
  * "iwstat" payload
@@ -66,8 +65,7 @@ static int iwstat_exec ( int argc, char **argv ) {
 /** "iwlist" command descriptor */
 static struct command_descriptor iwlist_cmd =
 	COMMAND_DESC ( struct ifcommon_options, ifcommon_opts, 0, MAX_ARGUMENTS,
-		       "[<interface>...]",
-		       "List wireless networks" );
+		       "[<interface>...]" );
 
 /**
  * "iwlist" payload

src/hci/commands/login_cmd.c

@@ -38,8 +38,7 @@ static struct option_descriptor login_opts[] = {};
 
 /** "login" command descriptor */
 static struct command_descriptor login_cmd =
-	COMMAND_DESC ( struct login_options, login_opts, 0, 0,
-		       "", "Prompt for login credentials" );
+	COMMAND_DESC ( struct login_options, login_opts, 0, 0, "" );
 
 /**
  * "login" command

src/hci/commands/lotest_cmd.c

@@ -49,8 +49,8 @@ static struct option_descriptor lotest_opts[] = {
 /** "lotest" command descriptor */
 static struct command_descriptor lotest_cmd =
 	COMMAND_DESC ( struct lotest_options, lotest_opts, 2, 2,
-		       "[--mtu <mtu>] <sending_interface> "
-		       "<receiving_interface>", "" );
+		       "[--mtu <mtu>] <sending interface> "
+		       "<receiving interface>" );
 
 /**
  * "lotest" command

src/hci/commands/nvo_cmd.c

@@ -42,8 +42,7 @@ static struct option_descriptor show_opts[] = {};
 
 /** "show" command descriptor */
 static struct command_descriptor show_cmd =
-	COMMAND_DESC ( struct show_options, show_opts, 1, 1,
-		       "<setting>", "" );
+	COMMAND_DESC ( struct show_options, show_opts, 1, 1, "<setting>" );
 
 /**
  * "show" command
@@ -88,7 +87,7 @@ static struct option_descriptor set_opts[] = {};
 /** "set" command descriptor */
 static struct command_descriptor set_cmd =
 	COMMAND_DESC ( struct set_options, set_opts, 1, MAX_ARGUMENTS,
-		       "<setting> <value>", "" );
+		       "<setting> <value>" );
 
 /**
  * "set" command
@@ -146,8 +145,7 @@ static struct option_descriptor clear_opts[] = {};
 
 /** "clear" command descriptor */
 static struct command_descriptor clear_cmd =
-	COMMAND_DESC ( struct clear_options, clear_opts, 1, 1,
-		       "<setting>", "" );
+	COMMAND_DESC ( struct clear_options, clear_opts, 1, 1, "<setting>" );
 
 /**
  * "clear" command

src/hci/commands/route_cmd.c

@@ -38,8 +38,7 @@ static struct option_descriptor route_opts[] = {};
 
 /** "route" command descriptor */
 static struct command_descriptor route_cmd =
-	COMMAND_DESC ( struct route_options, route_opts, 0, 0,
-		       "", "Display the routing table" );
+	COMMAND_DESC ( struct route_options, route_opts, 0, 0, "" );
 
 /**
  * The "route" command

src/hci/commands/sanboot_cmd.c

@@ -42,7 +42,7 @@ static struct option_descriptor sanboot_opts[] = {};
 /** "sanboot" command descriptor */
 static struct command_descriptor sanboot_cmd =
 	COMMAND_DESC ( struct sanboot_options, sanboot_opts, 1, 1,
-		       "<root-path>", "Boot from SAN target" );
+		       "<root-path>" );
 
 /**
  * The "sanboot" command

src/hci/commands/time_cmd.c

@@ -45,7 +45,7 @@ static struct option_descriptor time_opts[] = {};
 /** "time" command descriptor */
 static struct command_descriptor time_cmd =
 	COMMAND_DESC ( struct time_options, time_opts, 1, MAX_ARGUMENTS,
-		       "<command>", "Time a command" );
+		       "<command>" );
 
 /**
  * "time" command
@@ -87,8 +87,7 @@ static struct option_descriptor sleep_opts[] = {};
 
 /** "sleep" command descriptor */
 static struct command_descriptor sleep_cmd =
-	COMMAND_DESC ( struct sleep_options, sleep_opts, 1, 1,
-		       "<seconds>", "Sleep for <seconds> seconds" );
+	COMMAND_DESC ( struct sleep_options, sleep_opts, 1, 1, "<seconds>" );
 
 /**
  * "sleep" command

src/hci/commands/vlan_cmd.c

@@ -53,8 +53,7 @@ static struct option_descriptor vcreate_opts[] = {
 static struct command_descriptor vcreate_cmd =
 	COMMAND_DESC ( struct vcreate_options, vcreate_opts, 1, 1,
 		       "--tag <tag> [--priority <priority>] "
-		       "<trunk interface>",
-		       "Create a VLAN interface" );
+		       "<trunk interface>" );
 
 /**
  * "vcreate" command
@@ -95,8 +94,7 @@ static struct option_descriptor vdestroy_opts[] = {};
 /** "vdestroy" command descriptor */
 static struct command_descriptor vdestroy_cmd =
 	COMMAND_DESC ( struct vdestroy_options, vdestroy_opts, 1, 1,
-		       "<VLAN interface>",
-		       "Destroy a VLAN interface" );
+		       "<VLAN interface>" );
 
 /**
  * "vdestroy" command

src/hci/shell.c

@@ -97,8 +97,7 @@ static struct option_descriptor shell_opts[] = {};
 
 /** "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, "" );
 
 /**
  * "shell" command

src/image/script.c

@@ -218,8 +218,7 @@ static struct option_descriptor goto_opts[] = {};
 
 /** "goto" command descriptor */
 static struct command_descriptor goto_cmd =
-	COMMAND_DESC ( struct goto_options, goto_opts, 1, 1,
-		       "<label>", "" );
+	COMMAND_DESC ( struct goto_options, goto_opts, 1, 1, "<label>" );
 
 /**
  * Current "goto" label

src/include/ipxe/parseopt.h

@@ -81,12 +81,12 @@ struct command_descriptor {
 	uint8_t min_args;
 	/** Maximum number of non-option arguments */
 	uint8_t max_args;
-	/** Command usage and description
+	/** Command usage
 	 *
 	 * This excludes the literal "Usage:" and the command name,
 	 * which will be prepended automatically.
 	 */
-	const char *usage_description;
+	const char *usage;
 };
 
 /** No maximum number of arguments */
@@ -99,11 +99,9 @@ struct command_descriptor {
  * @v _options		Option descriptor array
  * @v _check_args	Remaining argument checker
  * @v _usage		Command usage
- * @v _description	Command description
  * @ret _command	Command descriptor
  */
-#define COMMAND_DESC( _struct, _options, _min_args, _max_args, _usage,	      \
-		      _description )					      \
+#define COMMAND_DESC( _struct, _options, _min_args, _max_args, _usage )	      \
 	{								      \
 		.options = ( ( ( ( typeof ( _options[0] ) * ) NULL ) ==	      \
 			       ( ( struct option_descriptor * ) NULL ) ) ?    \
@@ -113,7 +111,7 @@ struct command_descriptor {
 		.len = sizeof ( _struct ),				      \
 		.min_args = _min_args,					      \
 		.max_args = _max_args,					      \
-		.usage_description = _usage "\n\n" _description,	      \
+		.usage = _usage,					      \
 	 }
 
 extern int parse_string ( const char *text, const char **value );