busybox/libbb/getopt_ulflags.c
"Vladimir N. Oleynik" 064f04e7e2 - use complementally '!' to '?' - 'ask' is best 'free' char for this.
- more long opt compatibility, can set flag for long opt struct now
- more logic: check opt-depend requires and global requires, special for 'id' and 'start-stop-daemon' applets.
2005-10-11 14:38:01 +00:00

438 lines
13 KiB
C

/* vi: set sw=4 ts=4: */
/*
* universal getopt_ulflags implementation for busybox
*
* Copyright (C) 2003-2005 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_complementally (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.
(see getopt(3))
static const struct option applet_long_options[] = {
{ "verbose", 0, 0, v },
{ 0, 0, 0, 0 }
};
bb_applet_long_options = applet_long_options;
The last argument (val) can undefined from applet_opts.
If you use this, then:
- return bit have next position after short options
- if has_arg is not "no_argument", use ptr for arg also
- bb_opt_complementally have effects for this too
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_complementally
":" 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_complementally = "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.
"ww" Adjacent double options have a counter associated which indicates
the number of occurances of the option.
For example the ps applet needs:
if w is given once, GNU ps sets the width to 132,
if w is given more than once, it is "unlimited"
int w_counter = 0;
bb_opt_complementally = "ww";
bb_getopt_ulflags(argc, argv, "w", &w_counter);
if(w_counter)
width = (w_counter == 1) ? 132 : INT_MAX;
else
get_terminal_width(...&width...);
w_counter is a pointer to an integer. It has to be passed to
bb_getopt_ulflags() after all other option argument sinks.
For example: accept multiple -v to indicate the level of verbosity and
for each -b optarg, add optarg to my_b. Finally, if b is given, turn off
c and vice versa:
llist_t *my_b = NULL;
int verbose_level = 0;
bb_opt_complementally = "vv:b*:b-c:c-b";
f = bb_getopt_ulflags(argc, argv, "vb:c", &my_b, &verbose_level);
if((f & 2)) // -c after -b unset this -b flag
while (my_b) { dosomething_with(my_b->data) ; my_b = my_b->link; }
if(my_b) // but llist stored always if -b found
free_llist(my_b);
if (verbose_level) bb_printf("verbose level is %d\n", verbose_level);
Special characters:
"-" A dash between two options causes the second of the two
to be unset (and ignored or triggered) 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_complementally = "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_complementally = "s-d:d-s:x-x";
opt = bb_getopt_ulflags(argc, argv, "sd:x", &smax_print_depth);
if (opt & 2) {
max_print_depth = bb_xgetularg10_bnd(smax_print_depth,
0, INT_MAX);
}
if(opt & 4)
printf("Detected odd -x usaging\n");
"-" A minus as the first char in a bb_opt_complementally group means to
convert the arguments as option.
For example:
bb_opt_complementally = "-:w-x:x-w";
bb_getopt_ulflags(argc, argv, "wx");
Allows any arguments to be given without a dash (./program w x)
as well as with a dash (./program -x). Why unset -w see above.
"~" 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_complementally = "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 (BB_GETOPT_ERROR) so
that we can check for it:
if (flags & BB_GETOPT_ERROR)
bb_show_usage();
"?" A "ask" as the first char in a bb_opt_complementally group give:
if previous point set BB_GETOPT_ERROR, don`t return and
call previous example internally
"*" A star after a char in bb_opt_complementally 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_complementally = "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
"?" A "ask" between main and group options causes the second of the two
to be depending required if first is given on the command line.
For example from "id" applet:
// Don't allow -n -r -rn -ug -rug -nug -rnug
bb_opt_complementally = "?u~g:g~u:r?ug:n?ug";
flags = bb_getopt_ulflags(argc, argv, "rnug");
This example allowed only:
$ id; id -u; id -g; id -ru; id -nu; id -rg; id -ng; id -rnu; id -rng
"?" A "ask" between equivalent options in bb_opt_complementally means
requires this option always, checked after switch off from
complementally logic
For example from "start-stop-daemon" applet:
// Don't allow -KS -SK, but -S or -K required
bb_opt_complementally = "?:K?K:S?S:K~S:S~K";
flags = bb_getopt_ulflags(argc, argv, "KS...);
*/
const char *bb_opt_complementally;
typedef struct {
int opt;
int list_flg;
unsigned long switch_on;
unsigned long switch_off;
unsigned long incongruously;
unsigned long requires;
void **optarg; /* char **optarg or llist_t **optarg */
int *counter;
} t_complementally;
/* 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;
unsigned long requires = 0;
t_complementally complementally[sizeof(flags) * 8 + 1];
int c;
const unsigned char *s;
t_complementally *on_off;
va_list p;
const struct option *l_o;
unsigned long trigger;
char **pargv = NULL;
#define SHOW_USAGE_IF_ERROR 1
#define ARGV_IS_OPTS 2
int spec_flgs = 0;
va_start (p, applet_opts);
/* skip GNU extension */
s = applet_opts;
if(*s == '+' || *s == '-')
s++;
c = 0;
on_off = complementally;
memset(on_off, 0, sizeof(complementally));
for (; *s; s++) {
if(c >= (int)(sizeof(flags)*8))
break;
on_off->opt = *s;
on_off->switch_on = (1 << c);
if (s[1] == ':') {
on_off->optarg = va_arg (p, void **);
do
s++;
while (s[1] == ':');
}
on_off++;
c++;
}
for(l_o = bb_applet_long_options; l_o->name; l_o++) {
if(l_o->flag)
continue;
for(on_off = complementally; on_off->opt != 0; on_off++)
if(on_off->opt == l_o->val)
break;
if(on_off->opt == 0) {
if(c >= (int)(sizeof(flags)*8))
break;
on_off->opt = l_o->val;
on_off->switch_on = (1 << c);
if(l_o->has_arg != no_argument)
on_off->optarg = va_arg (p, void **);
c++;
}
}
c = 0;
for (s = bb_opt_complementally; s && *s; s++) {
t_complementally *pair;
if (*s == ':') {
c = 0;
continue;
}
if (c)
continue;
if(*s == '?') {
spec_flgs |= SHOW_USAGE_IF_ERROR;
continue;
}
if(*s == '-') {
spec_flgs |= ARGV_IS_OPTS;
continue;
}
for (on_off = complementally; on_off->opt; on_off++)
if (on_off->opt == *s)
break;
pair = on_off;
for(s++; *s && *s != ':'; s++) {
if (*s == '-' || *s == '~' || *s == '?') {
c = *s;
} else if(*s == '*') {
pair->list_flg++;
} else {
unsigned long *pair_switch;
switch(c) {
case '-':
pair_switch = &(pair->switch_off);
break;
case '~':
pair_switch = &(pair->incongruously);
break;
case '?':
pair_switch = &(pair->requires);
break;
default:
pair_switch = &(pair->switch_on);
}
for (on_off = complementally; on_off->opt; on_off++)
if (on_off->opt == *s) {
if(pair_switch == &(on_off->switch_on))
on_off->counter = va_arg (p, int *);
else if(pair_switch == &(on_off->requires))
requires |= on_off->switch_on;
else
*pair_switch |= on_off->switch_on;
break;
}
}
}
s--;
}
while ((c = getopt_long (argc, argv, applet_opts,
bb_applet_long_options, NULL)) >= 0) {
loop_arg_is_opt:
for (on_off = complementally; on_off->opt != c; on_off++) {
/* c==0 if long opt have non NULL flag */
if(on_off->opt == 0 && c != 0)
bb_show_usage ();
}
if(flags & on_off->incongruously) {
if((spec_flgs & SHOW_USAGE_IF_ERROR))
bb_show_usage ();
flags |= BB_GETOPT_ERROR;
}
trigger = on_off->switch_on & on_off->switch_off;
flags &= ~(on_off->switch_off ^ trigger);
flags |= on_off->switch_on ^ trigger;
flags ^= trigger;
if(on_off->counter)
(*(on_off->counter))++;
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;
}
if(pargv != NULL)
break;
}
if((spec_flgs & ARGV_IS_OPTS)) {
/* process argv is option, for example "ps" applet */
if(pargv == NULL)
pargv = argv + optind;
while(*pargv) {
c = **pargv;
if(c == '\0') {
pargv++;
} else {
(*pargv)++;
goto loop_arg_is_opt;
}
}
}
/* check depending requires for given options */
for (on_off = complementally; on_off->opt; on_off++) {
if(on_off->requires && (flags & on_off->switch_on) &&
(flags & on_off->requires) == 0)
bb_show_usage ();
}
if(requires && (flags & requires) == 0)
bb_show_usage ();
return flags;
}