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