transmission/libtransmission/tr-getopt.c

251 lines
6.2 KiB
C

/*
* This file Copyright (C) 2008-2014 Mnemosyne LLC
*
* It may be used under the GNU GPL versions 2 or 3
* or any future license endorsed by Mnemosyne LLC.
*
* $Id$
*/
#include <ctype.h> /* isspace () */
#include <stdio.h>
#include <stdlib.h> /* exit () */
#include <string.h>
#include "tr-getopt.h"
#ifndef MAX
#define MAX(a, b)(((a) > (b)) ? (a) : (b))
#endif
int tr_optind = 1;
static const char*
getArgName (const tr_option * opt)
{
const char * arg;
if (!opt->has_arg)
arg = "";
else if (opt->argName)
arg = opt->argName;
else
arg = "<args>";
return arg;
}
static int
get_next_line_len (const char * description, int maxlen)
{
int end;
int len = strlen (description);
if (len < maxlen)
return len;
end = maxlen < len ? maxlen : len;
while ((end > 0) && !isspace (description[end]))
--end;
return end ? end : len;
}
static void
getopts_usage_line (const tr_option * opt,
int longWidth,
int shortWidth,
int argWidth)
{
int len;
const char * longName = opt->longName ? opt->longName : "";
const char * shortName = opt->shortName ? opt->shortName : "";
const char * arg = getArgName (opt);
const int d_indent = shortWidth + longWidth + argWidth + 7;
const int d_width = 80 - d_indent;
const char * d = opt->description;
printf (" %s%-*s %s%-*s %-*s ",
(shortName && *shortName ? "-" : " "), shortWidth, shortName,
(longName && *longName ? "--" : " "), longWidth, longName,
argWidth, arg);
len = get_next_line_len (d, d_width);
printf ("%*.*s\n", len, len, d);
d += len;
while (isspace (*d)) ++d;
while ((len = get_next_line_len (d, d_width))) {
printf ("%*.*s%*.*s\n", d_indent, d_indent, "", len, len, d);
d += len;
while (isspace (*d)) ++d;
}
}
static void
maxWidth (const struct tr_option * o,
int * longWidth,
int * shortWidth,
int * argWidth)
{
const char * arg;
if (o->longName)
*longWidth = MAX (*longWidth, (int)strlen (o->longName));
if (o->shortName)
*shortWidth = MAX (*shortWidth, (int)strlen (o->shortName));
if ((arg = getArgName (o)))
*argWidth = MAX (*argWidth, (int)strlen (arg));
}
void
tr_getopt_usage (const char * progName,
const char * description,
const struct tr_option opts[])
{
int longWidth = 0;
int shortWidth = 0;
int argWidth = 0;
struct tr_option help;
const struct tr_option * o;
for (o = opts; o->val; ++o)
maxWidth (o, &longWidth, &shortWidth, &argWidth);
help.val = -1;
help.longName = "help";
help.description = "Display this help page and exit";
help.shortName = "h";
help.has_arg = 0;
maxWidth (&help, &longWidth, &shortWidth, &argWidth);
if (description == NULL)
description = "Usage: %s [options]";
printf (description, progName);
printf ("\n\nOptions:\n");
getopts_usage_line (&help, longWidth, shortWidth, argWidth);
for (o = opts; o->val; ++o)
getopts_usage_line (o, longWidth, shortWidth, argWidth);
}
static const tr_option *
findOption (const tr_option * opts,
const char * str,
const char ** setme_arg)
{
size_t matchlen = 0;
const char * arg = NULL;
const tr_option * o;
const tr_option * match = NULL;
/* find the longest matching option */
for (o = opts; o->val; ++o)
{
size_t len = o->longName ? strlen (o->longName) : 0;
if ((matchlen < len)
&& (str[0] == '-')
&& (str[1] == '-')
&& !strncmp (str+2, o->longName, len)
&& (str[len + 2] == '\0' || (o->has_arg && str[len + 2] == '=')))
{
matchlen = len;
match = o;
arg = str[len + 2] == '=' ? str + len + 3 : NULL;
}
len = o->shortName ? strlen (o->shortName) : 0;
if ((matchlen < len)
&& (str[0] == '-')
&& !strncmp (str+1, o->shortName, len)
&& (str[len + 1] == '\0' || o->has_arg))
{
matchlen = len;
match = o;
switch (str[len + 1])
{
case '\0':
arg = NULL; break;
case '=':
arg = str + len + 2; break;
default:
arg = str + len + 1; break;
}
}
}
if (setme_arg)
*setme_arg = arg;
return match;
}
int
tr_getopt (const char * usage,
int argc,
const char ** argv,
const tr_option * opts,
const char ** setme_optarg)
{
int i;
const char * arg = NULL;
const tr_option * o = NULL;
*setme_optarg = NULL;
/* handle the builtin 'help' option */
for (i = 1; i < argc; ++i)
{
if (!strcmp (argv[i], "-h") || !strcmp (argv[i], "--help"))
{
tr_getopt_usage (argv[0], usage, opts);
exit (0);
}
}
/* out of options? */
if (argc == 1 || tr_optind >= argc)
return TR_OPT_DONE;
o = findOption (opts, argv[tr_optind], &arg);
if (!o)
{
/* let the user know we got an unknown option... */
*setme_optarg = argv[tr_optind++];
return TR_OPT_UNK;
}
if (!o->has_arg)
{
/* no argument needed for this option, so we're done */
if (arg)
return TR_OPT_ERR;
*setme_optarg = NULL;
++tr_optind;
return o->val;
}
/* option needed an argument, and it was embedded in this string */
if (arg)
{
*setme_optarg = arg;
++tr_optind;
return o->val;
}
/* throw an error if the option needed an argument but didn't get one */
if (++tr_optind >= argc)
return TR_OPT_ERR;
if (findOption (opts, argv[tr_optind], NULL))
return TR_OPT_ERR;
*setme_optarg = argv[tr_optind++];
return o->val;
}