release/src/router/transmission/libtransmission/tr-getopt.c

   1 /*
   2  * This file Copyright (C) 2008-2014 Mnemosyne LLC
   3  *
   4  * It may be used under the GNU GPL versions 2 or 3
   5  * or any future license endorsed by Mnemosyne LLC.
   6  *
   7  * $Id: tr-getopt.c 14241 2014-01-21 03:10:30Z jordan $
   8  */
   9
  10 #include <ctype.h> /* isspace () */
  11 #include <stdio.h>
  12 #include <stdlib.h> /* exit () */
  13 #include <string.h>
  14
  15 #include "tr-getopt.h"
  16
  17 #ifndef MAX
  18  #define MAX(a, b)(((a) > (b)) ? (a) : (b))
  19 #endif
  20
  21 int tr_optind = 1;
  22
  23 static const char*
  24 getArgName (const tr_option * opt)
  25 {
  26     const char * arg;
  27
  28     if (!opt->has_arg)
  29         arg = "";
  30     else if (opt->argName)
  31         arg = opt->argName;
  32     else
  33         arg = "<args>";
  34
  35     return arg;
  36 }
  37
  38 static int
  39 get_next_line_len (const char * description, int maxlen)
  40 {
  41     int end;
  42     int len = strlen (description);
  43
  44     if (len < maxlen)
  45         return len;
  46
  47     end = maxlen < len ? maxlen : len;
  48     while ((end > 0) && !isspace (description[end]))
  49         --end;
  50
  51     return end ? end : len;
  52 }
  53
  54 static void
  55 getopts_usage_line (const tr_option * opt,
  56                     int               longWidth,
  57                     int               shortWidth,
  58                     int               argWidth)
  59 {
  60     int len;
  61     const char * longName   = opt->longName ? opt->longName : "";
  62     const char * shortName  = opt->shortName ? opt->shortName : "";
  63     const char * arg        = getArgName (opt);
  64
  65     const int d_indent = shortWidth + longWidth + argWidth + 7;
  66     const int d_width = 80 - d_indent;
  67     const char * d = opt->description;
  68
  69     printf (" %s%-*s %s%-*s %-*s ",
  70           (shortName && *shortName ? "-" : " "), shortWidth, shortName,
  71           (longName && *longName ? "--" : "  "), longWidth, longName,
  72             argWidth, arg);
  73     len = get_next_line_len (d, d_width);
  74     printf ("%*.*s\n", len, len, d);
  75
  76     d += len;
  77     while (isspace (*d)) ++d;
  78
  79     while ((len = get_next_line_len (d, d_width))) {
  80         printf ("%*.*s%*.*s\n", d_indent, d_indent, "", len, len, d);
  81         d += len;
  82         while (isspace (*d)) ++d;
  83     }
  84 }
  85
  86 static void
  87 maxWidth (const struct tr_option * o,
  88           int *                    longWidth,
  89           int *                    shortWidth,
  90           int *                    argWidth)
  91 {
  92     const char * arg;
  93
  94     if (o->longName)
  95         *longWidth = MAX (*longWidth, (int)strlen (o->longName));
  96
  97     if (o->shortName)
  98         *shortWidth = MAX (*shortWidth, (int)strlen (o->shortName));
  99
 100     if ((arg = getArgName (o)))
 101         *argWidth = MAX (*argWidth, (int)strlen (arg));
 102 }
 103
 104 void
 105 tr_getopt_usage (const char *           progName,
 106                  const char *           description,
 107                  const struct tr_option opts[])
 108 {
 109     int                      longWidth = 0;
 110     int                      shortWidth = 0;
 111     int                      argWidth = 0;
 112     struct tr_option         help;
 113     const struct tr_option * o;
 114
 115     for (o = opts; o->val; ++o)
 116         maxWidth (o, &longWidth, &shortWidth, &argWidth);
 117
 118     help.val = -1;
 119     help.longName = "help";
 120     help.description = "Display this help page and exit";
 121     help.shortName = "h";
 122     help.has_arg = 0;
 123     maxWidth (&help, &longWidth, &shortWidth, &argWidth);
 124
 125     if (description == NULL)
 126         description = "Usage: %s [options]";
 127     printf (description, progName);
 128     printf ("\n\nOptions:\n");
 129     getopts_usage_line (&help, longWidth, shortWidth, argWidth);
 130     for (o = opts; o->val; ++o)
 131         getopts_usage_line (o, longWidth, shortWidth, argWidth);
 132 }
 133
 134 static const tr_option *
 135 findOption (const tr_option * opts,
 136             const char *      str,
 137             const char **     setme_arg)
 138 {
 139     size_t            matchlen = 0;
 140     const char *      arg = NULL;
 141     const tr_option * o;
 142     const tr_option * match = NULL;
 143
 144     /* find the longest matching option */
 145     for (o = opts; o->val; ++o)
 146     {
 147         size_t len = o->longName ? strlen (o->longName) : 0;
 148
 149         if ((matchlen < len)
 150           && (str[0] == '-')
 151           && (str[1] == '-')
 152           && !strncmp (str+2, o->longName, len)
 153           && (str[len + 2] == '\0' || (o->has_arg && str[len + 2] == '=')))
 154         {
 155             matchlen = len;
 156             match = o;
 157             arg = str[len + 2] == '=' ? str + len + 3 : NULL;
 158         }
 159
 160         len = o->shortName ? strlen (o->shortName) : 0;
 161
 162         if ((matchlen < len)
 163           && (str[0] == '-')
 164           && !strncmp (str+1, o->shortName, len)
 165           && (str[len + 1] == '\0' || o->has_arg))
 166         {
 167             matchlen = len;
 168             match = o;
 169             switch (str[len + 1])
 170             {
 171                 case '\0':
 172                     arg = NULL;          break;
 173
 174                 case '=':
 175                     arg = str + len + 2; break;
 176
 177                 default:
 178                     arg = str + len + 1; break;
 179             }
 180         }
 181     }
 182
 183     if (setme_arg)
 184         *setme_arg = arg;
 185
 186     return match;
 187 }
 188
 189 int
 190 tr_getopt (const char *      usage,
 191            int               argc,
 192            const char **     argv,
 193            const tr_option * opts,
 194            const char **     setme_optarg)
 195 {
 196     int               i;
 197     const char *      arg = NULL;
 198     const tr_option * o = NULL;
 199
 200     *setme_optarg = NULL;
 201
 202     /* handle the builtin 'help' option */
 203     for (i = 1; i < argc; ++i)
 204     {
 205         if (!strcmp (argv[i], "-h") || !strcmp (argv[i], "--help"))
 206         {
 207             tr_getopt_usage (argv[0], usage, opts);
 208             exit (0);
 209         }
 210     }
 211
 212     /* out of options? */
 213     if (argc == 1 || tr_optind >= argc)
 214         return TR_OPT_DONE;
 215
 216     o = findOption (opts, argv[tr_optind], &arg);
 217     if (!o)
 218     {
 219         /* let the user know we got an unknown option... */
 220         *setme_optarg = argv[tr_optind++];
 221         return TR_OPT_UNK;
 222     }
 223
 224     if (!o->has_arg)
 225     {
 226         /* no argument needed for this option, so we're done */
 227         if (arg)
 228             return TR_OPT_ERR;
 229         *setme_optarg = NULL;
 230         ++tr_optind;
 231         return o->val;
 232     }
 233
 234     /* option needed an argument, and it was embedded in this string */
 235     if (arg)
 236     {
 237         *setme_optarg = arg;
 238         ++tr_optind;
 239         return o->val;
 240     }
 241
 242     /* throw an error if the option needed an argument but didn't get one */
 243     if (++tr_optind >= argc)
 244         return TR_OPT_ERR;
 245     if (findOption (opts, argv[tr_optind], NULL))
 246         return TR_OPT_ERR;
 247
 248     *setme_optarg = argv[tr_optind++];
 249     return o->val;
 250 }