transmission/libtransmission/tr-getopt.c

268 lines
6.0 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.
*
*/
#include <ctype.h> /* isspace() */
#include <stdio.h>
#include <stdlib.h> /* exit() */
#include <string.h>
#include "transmission.h"
#include "tr-getopt.h"
#include "tr-macros.h"
#include "utils.h"
int tr_optind = 1;
static char const* getArgName(tr_option const* opt)
{
char const* arg;
if (!opt->has_arg)
{
arg = "";
}
else if (opt->argName != NULL)
{
arg = opt->argName;
}
else
{
arg = "<args>";
}
return arg;
}
static int get_next_line_len(char const* 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 != 0 ? end : len;
}
static void getopts_usage_line(tr_option const* opt, int longWidth, int shortWidth, int argWidth)
{
int len;
char const* longName = opt->longName != NULL ? opt->longName : "";
char const* shortName = opt->shortName != NULL ? opt->shortName : "";
char const* arg = getArgName(opt);
int const d_indent = shortWidth + longWidth + argWidth + 7;
int const d_width = 80 - d_indent;
char const* d = opt->description;
printf(" %s%-*s %s%-*s %-*s ", tr_str_is_empty(shortName) ? " " : "-", shortWidth, shortName,
tr_str_is_empty(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)) != 0)
{
printf("%*.*s%*.*s\n", d_indent, d_indent, "", len, len, d);
d += len;
while (isspace(*d))
{
++d;
}
}
}
static void maxWidth(struct tr_option const* o, int* longWidth, int* shortWidth, int* argWidth)
{
char const* arg;
if (o->longName != NULL)
{
*longWidth = MAX(*longWidth, (int)strlen(o->longName));
}
if (o->shortName != NULL)
{
*shortWidth = MAX(*shortWidth, (int)strlen(o->shortName));
}
if ((arg = getArgName(o)) != NULL)
{
*argWidth = MAX(*argWidth, (int)strlen(arg));
}
}
void tr_getopt_usage(char const* progName, char const* description, struct tr_option const opts[])
{
int longWidth = 0;
int shortWidth = 0;
int argWidth = 0;
struct tr_option help;
for (tr_option const* o = opts; o->val != 0; ++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 = false;
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 (tr_option const* o = opts; o->val != 0; ++o)
{
getopts_usage_line(o, longWidth, shortWidth, argWidth);
}
}
static tr_option const* findOption(tr_option const* opts, char const* str, char const** setme_arg)
{
size_t matchlen = 0;
char const* arg = NULL;
tr_option const* match = NULL;
/* find the longest matching option */
for (tr_option const* o = opts; o->val != 0; ++o)
{
size_t len = o->longName != NULL ? strlen(o->longName) : 0;
if (matchlen < len && str[0] == '-' && str[1] == '-' && strncmp(str + 2, o->longName, len) == 0 &&
(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 != NULL ? strlen(o->shortName) : 0;
if (matchlen < len && str[0] == '-' && strncmp(str + 1, o->shortName, len) == 0 && (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 != NULL)
{
*setme_arg = arg;
}
return match;
}
int tr_getopt(char const* usage, int argc, char const* const* argv, tr_option const* opts, char const** setme_optarg)
{
char const* arg = NULL;
tr_option const* o = NULL;
*setme_optarg = NULL;
/* handle the builtin 'help' option */
for (int i = 1; i < argc; ++i)
{
if (strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "--help") == 0)
{
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 == NULL)
{
/* 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 != NULL)
{
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 != NULL)
{
*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) != NULL)
{
return TR_OPT_ERR;
}
*setme_optarg = argv[tr_optind++];
return o->val;
}