include/optutils.h

   1 #ifndef UTIL_LINUX_OPTUTILS_H
   2 #define UTIL_LINUX_OPTUTILS_H
   3
   4 #include <assert.h>
   5
   6 #include "c.h"
   7 #include "nls.h"
   8 #include "cctype.h"
   9
  10 static inline const char *option_to_longopt(int c, const struct option *opts)
  11 {
  12         const struct option *o;
  13
  14         assert(!(opts == NULL));
  15         for (o = opts; o->name; o++)
  16                 if (o->val == c)
  17                         return o->name;
  18         return NULL;
  19 }
  20
  21 #ifndef OPTUTILS_EXIT_CODE
  22 # define OPTUTILS_EXIT_CODE EXIT_FAILURE
  23 #endif
  24
  25 /*
  26  * Check collisions between options.
  27  *
  28  * The conflicts between options are described in ul_excl_t array. The
  29  * array contains groups of mutually exclusive options. For example
  30  *
  31  *      static const ul_excl_t excl[] = {
  32  *              { 'Z','b','c' },                // first group
  33  *              { 'b','x' },                    // second group
  34  *              { 0 }
  35  *      };
  36  *
  37  *      int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT;
  38  *
  39  *      while ((c = getopt_long(argc, argv, "Zbcx", longopts, NULL)) != -1) {
  40  *
  41  *              err_exclusive_options(c, longopts, excl, excl_st);
  42  *
  43  *              switch (c) {
  44  *              case 'Z':
  45  *                 ....
  46  *              }
  47  *      }
  48  *
  49  * The array excl[] defines two groups of the mutually exclusive options. The
  50  * option '-b' is in the both groups.
  51  *
  52  * Note that the options in the group have to be in ASCII order (ABC..abc..) and
  53  * groups have to be also in ASCII order.
  54  *
  55  * The maximal number of the options in the group is 15 (size of the array is
  56  * 16, last is zero).
  57  *
  58  * The current status of options is stored in excl_st array. The size of the array
  59  * must be the same as number of the groups in the ul_excl_t array.
  60  *
  61  * If you're unsure then see sys-utils/mount.c or misc-utils/findmnt.c.
  62  */
  63 #define UL_EXCL_STATUS_INIT     { 0 }
  64 typedef int ul_excl_t[16];
  65
  66 static inline void err_exclusive_options(
  67                         int c,
  68                         const struct option *opts,
  69                         const ul_excl_t *excl,
  70                         int *status)
  71 {
  72         int e;
  73
  74         for (e = 0; excl[e][0] && excl[e][0] <= c; e++) {
  75                 const int *op = excl[e];
  76
  77                 for (; *op && *op <= c; op++) {
  78                         if (*op != c)
  79                                 continue;
  80                         if (status[e] == 0)
  81                                 status[e] = c;
  82                         else if (status[e] != c) {
  83                                 size_t ct = 0;
  84
  85                                 fprintf(stderr, _("%s: mutually exclusive "
  86                                                   "arguments:"),
  87                                                 program_invocation_short_name);
  88
  89                                 for (op = excl[e];
  90                                      ct + 1 < ARRAY_SIZE(excl[0]) && *op;
  91                                      op++, ct++) {
  92                                         const char *n = option_to_longopt(*op, opts);
  93                                         if (n)
  94                                                 fprintf(stderr, " --%s", n);
  95                                         else if (c_isgraph(*op))
  96                                                 fprintf(stderr, " -%c", *op);
  97                                 }
  98                                 fputc('\n', stderr);
  99                                 exit(OPTUTILS_EXIT_CODE);
 100                         }
 101                         break;
 102                 }
 103         }
 104 }
 105
 106 #endif
 107