parse-options.hon commit Teach rebase the --no-ff option. (b499549)
   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        OPTION_NUMBER,
  10        /* options with no arguments */
  11        OPTION_BIT,
  12        OPTION_NEGBIT,
  13        OPTION_BOOLEAN, /* _INCR would have been a better name */
  14        OPTION_SET_INT,
  15        OPTION_SET_PTR,
  16        /* options with arguments (usually) */
  17        OPTION_STRING,
  18        OPTION_INTEGER,
  19        OPTION_CALLBACK,
  20        OPTION_FILENAME
  21};
  22
  23enum parse_opt_flags {
  24        PARSE_OPT_KEEP_DASHDASH = 1,
  25        PARSE_OPT_STOP_AT_NON_OPTION = 2,
  26        PARSE_OPT_KEEP_ARGV0 = 4,
  27        PARSE_OPT_KEEP_UNKNOWN = 8,
  28        PARSE_OPT_NO_INTERNAL_HELP = 16,
  29};
  30
  31enum parse_opt_option_flags {
  32        PARSE_OPT_OPTARG  = 1,
  33        PARSE_OPT_NOARG   = 2,
  34        PARSE_OPT_NONEG   = 4,
  35        PARSE_OPT_HIDDEN  = 8,
  36        PARSE_OPT_LASTARG_DEFAULT = 16,
  37        PARSE_OPT_NODASH = 32,
  38        PARSE_OPT_LITERAL_ARGHELP = 64,
  39        PARSE_OPT_NEGHELP = 128,
  40};
  41
  42struct option;
  43typedef int parse_opt_cb(const struct option *, const char *arg, int unset);
  44
  45/*
  46 * `type`::
  47 *   holds the type of the option, you must have an OPTION_END last in your
  48 *   array.
  49 *
  50 * `short_name`::
  51 *   the character to use as a short option name, '\0' if none.
  52 *
  53 * `long_name`::
  54 *   the long option name, without the leading dashes, NULL if none.
  55 *
  56 * `value`::
  57 *   stores pointers to the values to be filled.
  58 *
  59 * `argh`::
  60 *   token to explain the kind of argument this option wants. Keep it
  61 *   homogeneous across the repository.
  62 *
  63 * `help`::
  64 *   the short help associated to what the option does.
  65 *   Must never be NULL (except for OPTION_END).
  66 *   OPTION_GROUP uses this pointer to store the group header.
  67 *
  68 * `flags`::
  69 *   mask of parse_opt_option_flags.
  70 *   PARSE_OPT_OPTARG: says that the argument is optional (not for BOOLEANs)
  71 *   PARSE_OPT_NOARG: says that this option takes no argument
  72 *   PARSE_OPT_NONEG: says that this option cannot be negated
  73 *   PARSE_OPT_HIDDEN: this option is skipped in the default usage, and
  74 *                     shown only in the full usage.
  75 *   PARSE_OPT_LASTARG_DEFAULT: says that this option will take the default
  76 *                              value if no argument is given when the option
  77 *                              is last on the command line. If the option is
  78 *                              not last it will require an argument.
  79 *                              Should not be used with PARSE_OPT_OPTARG.
  80 *   PARSE_OPT_NODASH: this option doesn't start with a dash.
  81 *   PARSE_OPT_LITERAL_ARGHELP: says that argh shouldn't be enclosed in brackets
  82 *                              (i.e. '<argh>') in the help message.
  83 *                              Useful for options with multiple parameters.
  84 *   PARSE_OPT_NEGHELP: says that the long option should always be shown with
  85 *                              the --no prefix in the usage message. Sometimes
  86 *                              useful for users of OPTION_NEGBIT.
  87 *
  88 * `callback`::
  89 *   pointer to the callback to use for OPTION_CALLBACK.
  90 *
  91 * `defval`::
  92 *   default value to fill (*->value) with for PARSE_OPT_OPTARG.
  93 *   OPTION_{BIT,SET_INT,SET_PTR} store the {mask,integer,pointer} to put in
  94 *   the value when met.
  95 *   CALLBACKS can use it like they want.
  96 */
  97struct option {
  98        enum parse_opt_type type;
  99        int short_name;
 100        const char *long_name;
 101        void *value;
 102        const char *argh;
 103        const char *help;
 104
 105        int flags;
 106        parse_opt_cb *callback;
 107        intptr_t defval;
 108};
 109
 110#define OPT_END()                   { OPTION_END }
 111#define OPT_ARGUMENT(l, h)          { OPTION_ARGUMENT, 0, (l), NULL, NULL, \
 112                                      (h), PARSE_OPT_NOARG}
 113#define OPT_GROUP(h)                { OPTION_GROUP, 0, NULL, NULL, NULL, (h) }
 114#define OPT_BIT(s, l, v, h, b)      { OPTION_BIT, (s), (l), (v), NULL, (h), \
 115                                      PARSE_OPT_NOARG, NULL, (b) }
 116#define OPT_NEGBIT(s, l, v, h, b)   { OPTION_NEGBIT, (s), (l), (v), NULL, \
 117                                      (h), PARSE_OPT_NOARG, NULL, (b) }
 118#define OPT_BOOLEAN(s, l, v, h)     { OPTION_BOOLEAN, (s), (l), (v), NULL, \
 119                                      (h), PARSE_OPT_NOARG }
 120#define OPT_SET_INT(s, l, v, h, i)  { OPTION_SET_INT, (s), (l), (v), NULL, \
 121                                      (h), PARSE_OPT_NOARG, NULL, (i) }
 122#define OPT_SET_PTR(s, l, v, h, p)  { OPTION_SET_PTR, (s), (l), (v), NULL, \
 123                                      (h), PARSE_OPT_NOARG, NULL, (p) }
 124#define OPT_INTEGER(s, l, v, h)     { OPTION_INTEGER, (s), (l), (v), "n", (h) }
 125#define OPT_STRING(s, l, v, a, h)   { OPTION_STRING,  (s), (l), (v), (a), (h) }
 126#define OPT_UYN(s, l, v, h)         { OPTION_CALLBACK, (s), (l), (v), NULL, \
 127                                      (h), PARSE_OPT_NOARG, &parse_opt_tertiary }
 128#define OPT_DATE(s, l, v, h) \
 129        { OPTION_CALLBACK, (s), (l), (v), "time",(h), 0, \
 130          parse_opt_approxidate_cb }
 131#define OPT_CALLBACK(s, l, v, a, h, f) \
 132        { OPTION_CALLBACK, (s), (l), (v), (a), (h), 0, (f) }
 133#define OPT_NUMBER_CALLBACK(v, h, f) \
 134        { OPTION_NUMBER, 0, NULL, (v), NULL, (h), \
 135          PARSE_OPT_NOARG | PARSE_OPT_NONEG, (f) }
 136#define OPT_FILENAME(s, l, v, h)    { OPTION_FILENAME, (s), (l), (v), \
 137                                       "FILE", (h) }
 138#define OPT_COLOR_FLAG(s, l, v, h) \
 139        { OPTION_CALLBACK, (s), (l), (v), "when", (h), PARSE_OPT_OPTARG, \
 140                parse_opt_color_flag_cb, (intptr_t)"always" }
 141
 142
 143/* parse_options() will filter out the processed options and leave the
 144 * non-option arguments in argv[].
 145 * Returns the number of arguments left in argv[].
 146 */
 147extern int parse_options(int argc, const char **argv, const char *prefix,
 148                         const struct option *options,
 149                         const char * const usagestr[], int flags);
 150
 151extern NORETURN void usage_with_options(const char * const *usagestr,
 152                                        const struct option *options);
 153
 154extern NORETURN void usage_msg_opt(const char *msg,
 155                                   const char * const *usagestr,
 156                                   const struct option *options);
 157
 158/*----- incremental advanced APIs -----*/
 159
 160enum {
 161        PARSE_OPT_HELP = -1,
 162        PARSE_OPT_DONE,
 163        PARSE_OPT_UNKNOWN,
 164};
 165
 166/*
 167 * It's okay for the caller to consume argv/argc in the usual way.
 168 * Other fields of that structure are private to parse-options and should not
 169 * be modified in any way.
 170 */
 171struct parse_opt_ctx_t {
 172        const char **argv;
 173        const char **out;
 174        int argc, cpidx;
 175        const char *opt;
 176        int flags;
 177        const char *prefix;
 178};
 179
 180extern void parse_options_start(struct parse_opt_ctx_t *ctx,
 181                                int argc, const char **argv, const char *prefix,
 182                                int flags);
 183
 184extern int parse_options_step(struct parse_opt_ctx_t *ctx,
 185                              const struct option *options,
 186                              const char * const usagestr[]);
 187
 188extern int parse_options_end(struct parse_opt_ctx_t *ctx);
 189
 190
 191/*----- some often used options -----*/
 192extern int parse_opt_abbrev_cb(const struct option *, const char *, int);
 193extern int parse_opt_approxidate_cb(const struct option *, const char *, int);
 194extern int parse_opt_color_flag_cb(const struct option *, const char *, int);
 195extern int parse_opt_verbosity_cb(const struct option *, const char *, int);
 196extern int parse_opt_with_commit(const struct option *, const char *, int);
 197extern int parse_opt_tertiary(const struct option *, const char *, int);
 198
 199#define OPT__VERBOSE(var)  OPT_BOOLEAN('v', "verbose", (var), "be verbose")
 200#define OPT__QUIET(var)    OPT_BOOLEAN('q', "quiet",   (var), "be quiet")
 201#define OPT__VERBOSITY(var) \
 202        { OPTION_CALLBACK, 'v', "verbose", (var), NULL, "be more verbose", \
 203          PARSE_OPT_NOARG, &parse_opt_verbosity_cb, 0 }, \
 204        { OPTION_CALLBACK, 'q', "quiet", (var), NULL, "be more quiet", \
 205          PARSE_OPT_NOARG, &parse_opt_verbosity_cb, 0 }
 206#define OPT__DRY_RUN(var)  OPT_BOOLEAN('n', "dry-run", (var), "dry run")
 207#define OPT__ABBREV(var)  \
 208        { OPTION_CALLBACK, 0, "abbrev", (var), "n", \
 209          "use <n> digits to display SHA-1s", \
 210          PARSE_OPT_OPTARG, &parse_opt_abbrev_cb, 0 }
 211#define OPT__COLOR(var, h) \
 212        OPT_COLOR_FLAG(0, "color", (var), (h))
 213
 214#endif