parse-options.hon commit Documentation/hooks: add pre-auto-gc hook (0b85d92)
   1#ifndef PARSE_OPTIONS_H
   2#define PARSE_OPTIONS_H
   3
   4enum parse_opt_type {
   5        /* special types */
   6        OPTION_END,
   7        OPTION_ARGUMENT,
   8        OPTION_GROUP,
   9        /* options with no arguments */
  10        OPTION_BIT,
  11        OPTION_BOOLEAN, /* _INCR would have been a better name */
  12        OPTION_SET_INT,
  13        OPTION_SET_PTR,
  14        /* options with arguments (usually) */
  15        OPTION_STRING,
  16        OPTION_INTEGER,
  17        OPTION_CALLBACK,
  18};
  19
  20enum parse_opt_flags {
  21        PARSE_OPT_KEEP_DASHDASH = 1,
  22        PARSE_OPT_STOP_AT_NON_OPTION = 2,
  23};
  24
  25enum parse_opt_option_flags {
  26        PARSE_OPT_OPTARG  = 1,
  27        PARSE_OPT_NOARG   = 2,
  28        PARSE_OPT_NONEG   = 4,
  29        PARSE_OPT_HIDDEN  = 8,
  30};
  31
  32struct option;
  33typedef int parse_opt_cb(const struct option *, const char *arg, int unset);
  34
  35/*
  36 * `type`::
  37 *   holds the type of the option, you must have an OPTION_END last in your
  38 *   array.
  39 *
  40 * `short_name`::
  41 *   the character to use as a short option name, '\0' if none.
  42 *
  43 * `long_name`::
  44 *   the long option name, without the leading dashes, NULL if none.
  45 *
  46 * `value`::
  47 *   stores pointers to the values to be filled.
  48 *
  49 * `argh`::
  50 *   token to explain the kind of argument this option wants. Keep it
  51 *   homogenous across the repository.
  52 *
  53 * `help`::
  54 *   the short help associated to what the option does.
  55 *   Must never be NULL (except for OPTION_END).
  56 *   OPTION_GROUP uses this pointer to store the group header.
  57 *
  58 * `flags`::
  59 *   mask of parse_opt_option_flags.
  60 *   PARSE_OPT_OPTARG: says that the argument is optionnal (not for BOOLEANs)
  61 *   PARSE_OPT_NOARG: says that this option takes no argument, for CALLBACKs
  62 *   PARSE_OPT_NONEG: says that this option cannot be negated
  63 *   PARSE_OPT_HIDDEN this option is skipped in the default usage, showed in
  64 *                    the long one.
  65 *
  66 * `callback`::
  67 *   pointer to the callback to use for OPTION_CALLBACK.
  68 *
  69 * `defval`::
  70 *   default value to fill (*->value) with for PARSE_OPT_OPTARG.
  71 *   OPTION_{BIT,SET_INT,SET_PTR} store the {mask,integer,pointer} to put in
  72 *   the value when met.
  73 *   CALLBACKS can use it like they want.
  74 */
  75struct option {
  76        enum parse_opt_type type;
  77        int short_name;
  78        const char *long_name;
  79        void *value;
  80        const char *argh;
  81        const char *help;
  82
  83        int flags;
  84        parse_opt_cb *callback;
  85        intptr_t defval;
  86};
  87
  88#define OPT_END()                   { OPTION_END }
  89#define OPT_ARGUMENT(l, h)          { OPTION_ARGUMENT, 0, (l), NULL, NULL, (h) }
  90#define OPT_GROUP(h)                { OPTION_GROUP, 0, NULL, NULL, NULL, (h) }
  91#define OPT_BIT(s, l, v, h, b)      { OPTION_BIT, (s), (l), (v), NULL, (h), 0, NULL, (b) }
  92#define OPT_BOOLEAN(s, l, v, h)     { OPTION_BOOLEAN, (s), (l), (v), NULL, (h) }
  93#define OPT_SET_INT(s, l, v, h, i)  { OPTION_SET_INT, (s), (l), (v), NULL, (h), 0, NULL, (i) }
  94#define OPT_SET_PTR(s, l, v, h, p)  { OPTION_SET_PTR, (s), (l), (v), NULL, (h), 0, NULL, (p) }
  95#define OPT_INTEGER(s, l, v, h)     { OPTION_INTEGER, (s), (l), (v), NULL, (h) }
  96#define OPT_STRING(s, l, v, a, h)   { OPTION_STRING,  (s), (l), (v), (a), (h) }
  97#define OPT_DATE(s, l, v, h) \
  98        { OPTION_CALLBACK, (s), (l), (v), "time",(h), 0, \
  99          parse_opt_approxidate_cb }
 100#define OPT_CALLBACK(s, l, v, a, h, f) \
 101        { OPTION_CALLBACK, (s), (l), (v), (a), (h), 0, (f) }
 102
 103/* parse_options() will filter out the processed options and leave the
 104 * non-option argments in argv[].
 105 * Returns the number of arguments left in argv[].
 106 */
 107extern int parse_options(int argc, const char **argv,
 108                         const struct option *options,
 109                         const char * const usagestr[], int flags);
 110
 111extern NORETURN void usage_with_options(const char * const *usagestr,
 112                                        const struct option *options);
 113
 114/*----- some often used options -----*/
 115extern int parse_opt_abbrev_cb(const struct option *, const char *, int);
 116extern int parse_opt_approxidate_cb(const struct option *, const char *, int);
 117
 118#define OPT__VERBOSE(var)  OPT_BOOLEAN('v', "verbose", (var), "be verbose")
 119#define OPT__QUIET(var)    OPT_BOOLEAN('q', "quiet",   (var), "be quiet")
 120#define OPT__DRY_RUN(var)  OPT_BOOLEAN('n', "dry-run", (var), "dry run")
 121#define OPT__ABBREV(var)  \
 122        { OPTION_CALLBACK, 0, "abbrev", (var), "n", \
 123          "use <n> digits to display SHA-1s", \
 124          PARSE_OPT_OPTARG, &parse_opt_abbrev_cb, 0 }
 125
 126#endif