hush/libbb/getopt_ulflags.c

289 lines
9.5 KiB
C

/* vi: set sw=4 ts=4: */
/*
* universal getopt_ulflags implementation for busybox
*
* Copyright (C) 2003 Vladimir Oleynik <dzo@simtreas.ru>
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <getopt.h>
#include <string.h>
#include <assert.h>
#include <stdlib.h>
#include "libbb.h"
/* Documentation !
unsigned long
bb_getopt_ulflags (int argc, char **argv, const char *applet_opts, ...)
The command line options must be declared in const char
*applet_opts as a string of chars, for example:
flags = bb_getopt_ulflags(argc, argv, "rnug");
If one of the given options is found, a flag value is added to
the return value (an unsigned long).
The flag value is determined by the position of the char in
applet_opts string. For example, in the above case:
flags = bb_getopt_ulflags(argc, argv, "rnug");
"r" will add 1 (bit 1 : 0x01)
"n" will add 2 (bit 2 : 0x02)
"u will add 4 (bit 3 : 0x03)
"g" will add 8 (bit 4 : 0x04)
and so on. You can also look at the return value as a bit
field and each option sets one of bits.
":" If one of the options requires an argument, then add a ":"
after the char in applet_opts and provide a pointer to store
the argument. For example:
char *pointer_to_arg_for_a;
char *pointer_to_arg_for_b;
char *pointer_to_arg_for_c;
char *pointer_to_arg_for_d;
flags = bb_getopt_ulflags(argc, argv, "a:b:c:d:",
&pointer_to_arg_for_a, &pointer_to_arg_for_b,
&pointer_to_arg_for_c, &pointer_to_arg_for_d);
The type of the pointer (char* or llist_t *) may be controlled
by the "*" special character that is set in the external string
bb_opt_complementaly (see below for more info).
static const struct option bb_default_long_options[]
This struct allows you to define long options. The syntax for
declaring the array is just like that of getopt's longopts.
static const struct option applet_long_options[] = {
{ "verbose", 0, 0, "v" },
{ 0, 0, 0, 0 }
};
bb_applet_long_options = applet_long_options;
The first parameter is the long option that you would pass to
the applet (--verbose) in place of the short option (-v). The
second field determines whether the option has an argument.
You can set this to 0, 1, or 2, or you can use the long named
defines of no_argument, required_argument, and optional_argument.
Just set the third argument to '0' or 'NULL'. The last argument
is simply the short option without the dash of course.
Note: a good applet will make long options configurable via the
config process and not a required feature. The current standard
is to name the config option CONFIG_FEATURE_<applet>_LONG_OPTIONS.
const char *bb_opt_complementaly
":" The colon (":") is used to separate groups of two or more chars
and/or groups of chars and special characters (stating some
conditions to be checked).
"abc" If groups of two or more chars are specified, the first char
is the main option and the other chars are secondary options.
Their flags will be turned on if the main option is found even
if they are not specifed on the command line. For example:
bb_opt_complementaly = "abc";
flags = bb_getopt_ulflags(argc, argv, "abcd")
If getopt() finds "-a" on the command line, then
bb_getopt_ulflags's return value will be as if "-a -b -c" were
found.
Special characters:
"-" A dash between two options causes the second of the two
to be unset (and ignored) if it is given on the command line.
For example:
The du applet has the options "-s" and "-d depth". If
bb_getopt_ulflags finds -s, then -d is unset or if it finds -d
then -s is unset. (Note: busybox implements the GNU
"--max-depth" option as "-d".) To obtain this behavior, you
set bb_opt_complementaly = "s-d:d-s". Only one flag value is
added to bb_getopt_ulflags's return value depending on the
position of the options on the command line. If one of the
two options requires an argument pointer (":" in applet_opts
as in "d:") optarg is set accordingly.
char *smax_print_depth;
bb_opt_complementaly = "s-d:d-s";
opt = bb_getopt_ulflags(argc, argv, "sd:", &smax_print_depth);
if (opt & 2) {
max_print_depth = bb_xgetularg10_bnd(smax_print_depth,
0, INT_MAX);
}
"~" A tilde between two options, or between an option and a group
of options, means that they are mutually exclusive. Unlike
the "-" case above, an error will be forced if the options
are used together.
For example:
The cut applet must have only one type of list specified, so
-b, -c and -f are mutally exclusive and should raise an error
if specified together. In this case you must set
bb_opt_complementaly = "b~cf:c~bf:f~bc". If two of the
mutually exclusive options are found, bb_getopt_ulflags's
return value will have the error flag set (0x80000000UL) so
that we can check for it:
if (flags & 0x80000000UL)
bb_show_usage();
"*" A star after a char in bb_opt_complementaly means that the
option can occur multiple times:
For example:
The grep applet can have one or more "-e pattern" arguments.
In this case you should use bb_getopt_ulflags() as follows:
llist_t *patterns = NULL;
(this pointer must be initializated to NULL if the list is empty
as required by *llist_add_to(llist_t *old_head, char *new_item).)
bb_opt_complementaly = "e*";
bb_getopt_ulflags(argc, argv, "e:", &patterns);
$ grep -e user -e root /etc/passwd
root:x:0:0:root:/root:/bin/bash
user:x:500:500::/home/user:/bin/bash
*/
const char *bb_opt_complementaly;
typedef struct {
unsigned char opt;
char list_flg;
unsigned long switch_on;
unsigned long switch_off;
unsigned long incongruously;
void **optarg; /* char **optarg or llist_t **optarg */
} t_complementaly;
/* You can set bb_applet_long_options for parse called long options */
static const struct option bb_default_long_options[] = {
/* { "help", 0, NULL, '?' }, */
{ 0, 0, 0, 0 }
};
const struct option *bb_applet_long_options = bb_default_long_options;
unsigned long
bb_getopt_ulflags (int argc, char **argv, const char *applet_opts, ...)
{
unsigned long flags = 0;
t_complementaly complementaly[sizeof(flags) * 8 + 1];
int c;
const unsigned char *s;
t_complementaly *on_off;
va_list p;
va_start (p, applet_opts);
/* skip GNU extension */
s = applet_opts;
if(*s == '+' || *s == '-')
s++;
c = 0;
on_off = complementaly;
for (; *s; s++) {
if(c >= (sizeof(flags)*8))
break;
on_off->opt = *s;
on_off->switch_on = (1 << c);
on_off->list_flg = 0;
on_off->switch_off = 0;
on_off->incongruously = 0;
on_off->optarg = NULL;
if (s[1] == ':') {
on_off->optarg = va_arg (p, void **);
do
s++;
while (s[1] == ':');
}
on_off++;
c++;
}
on_off->opt = 0;
c = 0;
for (s = bb_opt_complementaly; s && *s; s++) {
t_complementaly *pair;
if (*s == ':') {
c = 0;
continue;
}
if (c)
continue;
for (on_off = complementaly; on_off->opt; on_off++)
if (on_off->opt == *s)
break;
pair = on_off;
for(s++; *s && *s != ':'; s++) {
if (*s == '-' || *s == '~') {
c = *s;
} else if(*s == '*') {
pair->list_flg++;
} else {
unsigned long *pair_switch = &(pair->switch_on);
if(c)
pair_switch = c == '-' ? &(pair->switch_off) : &(pair->incongruously);
for (on_off = complementaly; on_off->opt; on_off++)
if (on_off->opt == *s) {
*pair_switch |= on_off->switch_on;
break;
}
}
}
s--;
}
while ((c = getopt_long (argc, argv, applet_opts,
bb_applet_long_options, NULL)) > 0) {
for (on_off = complementaly; on_off->opt != c; on_off++) {
if(!on_off->opt)
bb_show_usage ();
}
if(flags & on_off->incongruously)
flags |= 0x80000000UL;
flags &= ~on_off->switch_off;
flags |= on_off->switch_on;
if(on_off->list_flg) {
*(llist_t **)(on_off->optarg) =
llist_add_to(*(llist_t **)(on_off->optarg), optarg);
} else if (on_off->optarg) {
*(char **)(on_off->optarg) = optarg;
}
}
return flags;
}