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