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>
94 lines
2.4 KiB
C
94 lines
2.4 KiB
C
/*
|
|
* Copyright (C) 2012 Jan Luebbe <j.luebbe@pengutronix.de>
|
|
*
|
|
* Partially based on code from BusyBox.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <command.h>
|
|
#include <environment.h>
|
|
#include <errno.h>
|
|
#include <init.h>
|
|
#include <malloc.h>
|
|
#include <xfuncs.h>
|
|
#include <math.h>
|
|
|
|
static void setvar(const char *name, const char *val)
|
|
{
|
|
setenv(name, val); /* return value is always 0 */
|
|
}
|
|
|
|
static arith_t run_arith(const char *s)
|
|
{
|
|
arith_state_t math_state;
|
|
arith_t result;
|
|
|
|
math_state.lookupvar = getenv;
|
|
math_state.setvar = setvar;
|
|
math_state.endofname = arith_endofname;
|
|
|
|
result = arith(&math_state, s);
|
|
if (math_state.errmsg)
|
|
printf("let: %s\n", math_state.errmsg);
|
|
|
|
return result;
|
|
}
|
|
|
|
static int do_let(int argc, char *argv[])
|
|
{
|
|
arith_t i;
|
|
|
|
argv++;
|
|
if (!*argv) {
|
|
printf("let: expression expected\n");
|
|
return COMMAND_ERROR_USAGE;
|
|
}
|
|
|
|
do {
|
|
i = run_arith(*argv);
|
|
} while (*++argv);
|
|
|
|
return !i;
|
|
}
|
|
|
|
BAREBOX_CMD_HELP_START(let)
|
|
BAREBOX_CMD_HELP_TEXT ("Supported operations are in order of decreasing precedence:")
|
|
BAREBOX_CMD_HELP_TEXT (" X++, X--")
|
|
BAREBOX_CMD_HELP_TEXT (" ++X, --X")
|
|
BAREBOX_CMD_HELP_TEXT (" +X, -X")
|
|
BAREBOX_CMD_HELP_TEXT (" !X, ~X")
|
|
BAREBOX_CMD_HELP_TEXT (" X**Y")
|
|
BAREBOX_CMD_HELP_TEXT (" X*Y, X/Y, X%Y")
|
|
BAREBOX_CMD_HELP_TEXT (" X+Y, X-Y")
|
|
BAREBOX_CMD_HELP_TEXT (" X<<Y, X>>Y")
|
|
BAREBOX_CMD_HELP_TEXT (" X<Y, X<=Y, X>=Y, X>Y")
|
|
BAREBOX_CMD_HELP_TEXT (" X==Y, X!=Y")
|
|
BAREBOX_CMD_HELP_TEXT (" X&Y")
|
|
BAREBOX_CMD_HELP_TEXT (" X^Y")
|
|
BAREBOX_CMD_HELP_TEXT (" X|Y")
|
|
BAREBOX_CMD_HELP_TEXT (" X&&Y")
|
|
BAREBOX_CMD_HELP_TEXT (" X||Y")
|
|
BAREBOX_CMD_HELP_TEXT (" X?Y:Z")
|
|
BAREBOX_CMD_HELP_TEXT (" X*=Y, X/=Y, X%=Y")
|
|
BAREBOX_CMD_HELP_TEXT (" X=Y, X&=Y, X|=Y, X^=Y, X+=Y, X-=Y, X<<=Y, X>>=Y")
|
|
BAREBOX_CMD_HELP_END
|
|
|
|
BAREBOX_CMD_START(let)
|
|
.cmd = do_let,
|
|
BAREBOX_CMD_DESC("evaluate arithmetic expressions")
|
|
BAREBOX_CMD_OPTS("EXPR [EXPR ...]")
|
|
BAREBOX_CMD_GROUP(CMD_GRP_SCRIPT)
|
|
BAREBOX_CMD_HELP(cmd_let_help)
|
|
BAREBOX_CMD_END
|