commands: harmonize in-barebox documentation

This patch does probably too much, but it's hard (and very
cumbersome/time consuming) to break it out. What is does is this:

* each command has one short description, e.g. "list MUX configuration"
* made sure the short descriptions start lowercase
* each command has one usage. That string contains just the
  options, e.g. "[-npn]". It's not part of the long help text.
* that is, it doesn't say "[OPTIONS]" anymore, every usable option
  is listed by character in this (short) option string (the long
  description is in the long help text, as before)
* help texts have been reworked, to make them
  - sometimes smaller
  - sometimes describe the options better
  - more often present themselves in a nicer format
* all long help texts are now created with BUSYBOX_CMD_HELP_
  macros, no more 'static const __maybe_unused char cmd_foobar_help[]'
* made sure the long help texts starts uppercase
* because cmdtp->name and cmdtp->opts together provide the new usage,
  all "Usage: foobar" texts have been removed from the long help texts
* BUSYBOX_CMD_HELP_TEXT() provides the trailing newline by itself, this
  is nicer in the source code
* BUSYBOX_CMD_HELP_OPT() provides the trailing newline by itself
* made sure no line gets longer than 77 characters
* delibertely renamed cmdtp->usage, so that we can get compile-time
  errors (e.g. in out-of-tree modules that use register_command()
* the 'help' command can now always emit the usage, even without
  compiled long help texts
* 'help -v' gives a list of commands with their short description, this
  is similar like the old "help" command before my patchset
* 'help -a' gives out help of all commands

Signed-off-by: Holger Schurig <holgerschurig@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

2 files changed, 36 insertions, 53 deletions

diff --git a/common/command.c b/common/command.c
index 7f2b777939..61191c2d62 100644
--- a/common/command.c
+++ b/common/command.c
@@ -36,22 +36,18 @@ EXPORT_SYMBOL(command_list);
 
 void barebox_cmd_usage(struct command *cmdtp)
 {
-#ifdef	CONFIG_LONGHELP
-		/* found - print (long) help info */
-		if (cmdtp->help) {
-			puts (cmdtp->help);
-		} else {
-			puts (cmdtp->name);
-			putchar (' ');
-			puts ("- No help available.\n");
-		}
-		putchar ('\n');
-#else	/* no long help available */
-		if (cmdtp->usage) {
-			puts (cmdtp->usage);
-			puts("\n");
-		}
-#endif	/* CONFIG_LONGHELP */
+	putchar('\n');
+	if (cmdtp->desc)
+		printf("%s - %s\n\n", cmdtp->name, cmdtp->desc);
+	if (cmdtp->opts)
+		printf("Usage: %s %s\n\n", cmdtp->name, cmdtp->opts);
+#ifdef CONFIG_LONGHELP
+	/* found - print (long) help info */
+	if (cmdtp->help) {
+		puts(cmdtp->help);
+		putchar('\n');
+	}
+#endif
 }
 EXPORT_SYMBOL(barebox_cmd_usage);
 
@@ -108,14 +104,13 @@ int register_command(struct command *cmd)
 	if (cmd->aliases) {
 		char **aliases = (char**)cmd->aliases;
 		while(*aliases) {
-			char *usage = "alias for ";
 			struct command *c = xzalloc(sizeof(struct command));
 
 			memcpy(c, cmd, sizeof(struct command));
 
 			c->name = *aliases;
-			c->usage = xmalloc(strlen(usage) + strlen(cmd->name) + 1);
-			sprintf((char*)c->usage, "%s%s", usage, cmd->name);
+			c->desc = cmd->desc;
+			c->opts = cmd->opts;
 
 			c->aliases = NULL;
 
@@ -163,4 +158,3 @@ static int init_command_list(void)
 }
 
 late_initcall(init_command_list);
-
diff --git a/common/hush.c b/common/hush.c
index 5893c5129b..92f95766a7 100644
--- a/common/hush.c
+++ b/common/hush.c
@@ -1932,16 +1932,11 @@ static int do_sh(int argc, char *argv[])
 	return execute_script(argv[1], argc - 1, argv + 1);
 }
 
-static const __maybe_unused char cmd_sh_help[] =
-"Usage: sh filename [arguments]\n"
-"\n"
-"Execute a shell script\n";
-
 BAREBOX_CMD_START(sh)
 	.cmd		= do_sh,
-	.usage		= "run shell script",
+	BAREBOX_CMD_DESC("execute a shell script")
+	BAREBOX_CMD_OPTS("FILE [ARGUMENT...]")
 	BAREBOX_CMD_GROUP(CMD_GRP_SCRIPT)
-	BAREBOX_CMD_HELP(cmd_sh_help)
 BAREBOX_CMD_END
 
 static int do_source(int argc, char *argv[])
@@ -1969,21 +1964,16 @@ static int do_source(int argc, char *argv[])
 
 static const char *source_aliases[] = { ".", NULL};
 
-static const __maybe_unused char cmd_source_help[] =
-"Usage: .  filename [arguments]\n"
-"or     source filename [arguments]\n"
-"\n"
-"Read  and  execute  commands  from filename in the current shell\n"
-"environment and return the exit status of the last command  exe-\n"
-"cuted from filename\n";
-
-static const __maybe_unused char cmd_source_usage[] =
-"execute shell script in current shell environment";
+BAREBOX_CMD_HELP_START(source)
+BAREBOX_CMD_HELP_TEXT("Read and execute commands from FILE in the current shell environment.")
+BAREBOX_CMD_HELP_TEXT("and return the exit status of the last command executed.")
+BAREBOX_CMD_HELP_END
 
 BAREBOX_CMD_START(source)
 	.aliases	= source_aliases,
 	.cmd		= do_source,
-	.usage		= cmd_source_usage,
+	BAREBOX_CMD_DESC("execute shell script in current shell environment")
+	BAREBOX_CMD_OPTS("FILE [ARGUMENT...]")
 	BAREBOX_CMD_GROUP(CMD_GRP_SCRIPT)
 	BAREBOX_CMD_HELP(cmd_source_help)
 BAREBOX_CMD_END
@@ -1997,32 +1987,31 @@ static int do_dummy_command(int argc, char *argv[])
 	return 0;
 }
 
-static const __maybe_unused char cmd_exit_help[] =
-"Usage: exit [n]\n"
-"\n"
-"exit script with a status of n. If n is omitted, the exit status is that\n"
-"of the last command executed\n";
+BAREBOX_CMD_HELP_START(exit)
+BAREBOX_CMD_HELP_TEXT("Exit script with status ERRLVL n. If ERRLVL is omitted, the exit status is")
+BAREBOX_CMD_HELP_TEXT("of the last command executed")
+BAREBOX_CMD_HELP_END
 
 BAREBOX_CMD_START(exit)
 	.cmd		= do_dummy_command,
-	.usage		= "exit script",
+	BAREBOX_CMD_DESC("exit script")
+	BAREBOX_CMD_OPTS("[ERRLVL]")
 	BAREBOX_CMD_GROUP(CMD_GRP_SCRIPT)
 	BAREBOX_CMD_HELP(cmd_exit_help)
 BAREBOX_CMD_END
 
 #ifdef CONFIG_HUSH_GETOPT
-static const __maybe_unused char cmd_getopt_help[] =
-"Usage: getopt <optstring> <var>\n"
-"\n"
-"hush option parser. <optstring> is a string with valid options. Add\n"
-"a colon to an options if this option has a required argument or two\n"
-"colons for an optional argument. The current option is saved in <var>,\n"
-"arguments are saved in OPTARG. After this command additional nonopts\n"
-"can be accessed starting from $1\n";
+BAREBOX_CMD_HELP_START(getopt)
+BAREBOX_CMD_HELP_TEXT("OPTSTRING contains the option letters. Add a colon to an options if this")
+BAREBOX_CMD_HELP_TEXT("option has a required argument or two colons for an optional argument. The")
+BAREBOX_CMD_HELP_TEXT("current option is saved in VAR, arguments are saved in $OPTARG. Any")
+BAREBOX_CMD_HELP_TEXT("non-option arguments can be accessed starting from $1.")
+BAREBOX_CMD_HELP_END
 
 BAREBOX_CMD_START(getopt)
 	.cmd		= do_dummy_command,
-	.usage		= "getopt <optstring> <var>",
+	BAREBOX_CMD_DESC("parse option arguments")
+	BAREBOX_CMD_OPTS("OPTSTRING VAR")
 	BAREBOX_CMD_GROUP(CMD_GRP_SCRIPT)
 	BAREBOX_CMD_HELP(cmd_getopt_help)
 BAREBOX_CMD_END