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_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
  23 enum 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
  31 enum 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
  42 struct option;
  43 typedef 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  */
  97 struct 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  */
 147 extern int parse_options(int argc, const char **argv, const char *prefix,
 148                          const struct option *options,
 149                          const char * const usagestr[], int flags);
 150
 151 extern NORETURN void usage_with_options(const char * const *usagestr,
 152                                         const struct option *options);
 153
 154 extern NORETURN void usage_msg_opt(const char *msg,
 155                                    const char * const *usagestr,
 156                                    const struct option *options);
 157
 158 /*----- incremental advanced APIs -----*/
 159
 160 enum {
 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  */
 171 struct 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
 180 extern void parse_options_start(struct parse_opt_ctx_t *ctx,
 181                                 int argc, const char **argv, const char *prefix,
 182                                 int flags);
 183
 184 extern int parse_options_step(struct parse_opt_ctx_t *ctx,
 185                               const struct option *options,
 186                               const char * const usagestr[]);
 187
 188 extern int parse_options_end(struct parse_opt_ctx_t *ctx);
 189
 190
 191 /*----- some often used options -----*/
 192 extern int parse_opt_abbrev_cb(const struct option *, const char *, int);
 193 extern int parse_opt_approxidate_cb(const struct option *, const char *, int);
 194 extern int parse_opt_color_flag_cb(const struct option *, const char *, int);
 195 extern int parse_opt_verbosity_cb(const struct option *, const char *, int);
 196 extern int parse_opt_with_commit(const struct option *, const char *, int);
 197 extern 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