parse-options.h

   1 #ifndef PARSE_OPTIONS_H
   2 #define PARSE_OPTIONS_H
   3
   4 enum parse_opt_type {
   5         /* special types */
   6         OPTION_END,
   7         OPTION_GROUP,
   8         /* options with no arguments */
   9         OPTION_BIT,
  10         OPTION_BOOLEAN, /* _INCR would have been a better name */
  11         OPTION_SET_INT,
  12         OPTION_SET_PTR,
  13         /* options with arguments (usually) */
  14         OPTION_STRING,
  15         OPTION_INTEGER,
  16         OPTION_CALLBACK,
  17 };
  18
  19 enum parse_opt_flags {
  20         PARSE_OPT_KEEP_DASHDASH = 1,
  21 };
  22
  23 enum parse_opt_option_flags {
  24         PARSE_OPT_OPTARG  = 1,
  25         PARSE_OPT_NOARG   = 2,
  26         PARSE_OPT_NONEG   = 4,
  27         PARSE_OPT_HIDDEN  = 8,
  28 };
  29
  30 struct option;
  31 typedef int parse_opt_cb(const struct option *, const char *arg, int unset);
  32
  33 /*
  34  * `type`::
  35  *   holds the type of the option, you must have an OPTION_END last in your
  36  *   array.
  37  *
  38  * `short_name`::
  39  *   the character to use as a short option name, '\0' if none.
  40  *
  41  * `long_name`::
  42  *   the long option name, without the leading dashes, NULL if none.
  43  *
  44  * `value`::
  45  *   stores pointers to the values to be filled.
  46  *
  47  * `argh`::
  48  *   token to explain the kind of argument this option wants. Keep it
  49  *   homogenous across the repository.
  50  *
  51  * `help`::
  52  *   the short help associated to what the option does.
  53  *   Must never be NULL (except for OPTION_END).
  54  *   OPTION_GROUP uses this pointer to store the group header.
  55  *
  56  * `flags`::
  57  *   mask of parse_opt_option_flags.
  58  *   PARSE_OPT_OPTARG: says that the argument is optionnal (not for BOOLEANs)
  59  *   PARSE_OPT_NOARG: says that this option takes no argument, for CALLBACKs
  60  *   PARSE_OPT_NONEG: says that this option cannot be negated
  61  *   PARSE_OPT_HIDDEN this option is skipped in the default usage, showed in
  62  *                    the long one.
  63  *
  64  * `callback`::
  65  *   pointer to the callback to use for OPTION_CALLBACK.
  66  *
  67  * `defval`::
  68  *   default value to fill (*->value) with for PARSE_OPT_OPTARG.
  69  *   OPTION_{BIT,SET_INT,SET_PTR} store the {mask,integer,pointer} to put in
  70  *   the value when met.
  71  *   CALLBACKS can use it like they want.
  72  */
  73 struct option {
  74         enum parse_opt_type type;
  75         int short_name;
  76         const char *long_name;
  77         void *value;
  78         const char *argh;
  79         const char *help;
  80
  81         int flags;
  82         parse_opt_cb *callback;
  83         intptr_t defval;
  84 };
  85
  86 #define OPT_END()                   { OPTION_END }
  87 #define OPT_GROUP(h)                { OPTION_GROUP, 0, NULL, NULL, NULL, (h) }
  88 #define OPT_BIT(s, l, v, h, b)      { OPTION_BIT, (s), (l), (v), NULL, (h), 0, NULL, (b) }
  89 #define OPT_BOOLEAN(s, l, v, h)     { OPTION_BOOLEAN, (s), (l), (v), NULL, (h) }
  90 #define OPT_SET_INT(s, l, v, h, i)  { OPTION_SET_INT, (s), (l), (v), NULL, (h), 0, NULL, (i) }
  91 #define OPT_SET_PTR(s, l, v, h, p)  { OPTION_SET_PTR, (s), (l), (v), NULL, (h), 0, NULL, (p) }
  92 #define OPT_INTEGER(s, l, v, h)     { OPTION_INTEGER, (s), (l), (v), NULL, (h) }
  93 #define OPT_STRING(s, l, v, a, h)   { OPTION_STRING,  (s), (l), (v), (a), (h) }
  94 #define OPT_CALLBACK(s, l, v, a, h, f) \
  95         { OPTION_CALLBACK, (s), (l), (v), (a), (h), 0, (f) }
  96
  97 /* parse_options() will filter out the processed options and leave the
  98  * non-option argments in argv[].
  99  * Returns the number of arguments left in argv[].
 100  */
 101 extern int parse_options(int argc, const char **argv,
 102                          const struct option *options,
 103                          const char * const usagestr[], int flags);
 104
 105 extern NORETURN void usage_with_options(const char * const *usagestr,
 106                                         const struct option *options);
 107
 108 /*----- some often used options -----*/
 109 extern int parse_opt_abbrev_cb(const struct option *, const char *, int);
 110
 111 #define OPT__VERBOSE(var)  OPT_BOOLEAN('v', "verbose", (var), "be verbose")
 112 #define OPT__QUIET(var)    OPT_BOOLEAN('q', "quiet",   (var), "be quiet")
 113 #define OPT__DRY_RUN(var)  OPT_BOOLEAN('n', "dry-run", (var), "dry run")
 114 #define OPT__ABBREV(var)  \
 115         { OPTION_CALLBACK, 0, "abbrev", (var), "n", \
 116           "use <n> digits to display SHA-1s", \
 117           PARSE_OPT_OPTARG, &parse_opt_abbrev_cb, 0 }
 118
 119 #endif