parseopt.h

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#ifndef _IPXE_PARSEOPT_H
#define _IPXE_PARSEOPT_H

/** @file
 *
 * Command line option parsing
 *
 */

FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );

#include <stdint.h>
#include <stddef.h>
#include <ipxe/uuid.h>
#include <ipxe/settings.h>

struct net_device;
struct net_device_configurator;
struct menu;
struct parameters;

/** A command-line option descriptor */
struct option_descriptor {
        /** Long option name, if any */
        const char *longopt;
        /** Short option name */
        char shortopt;
        /** Argument requirement (as for @c struct @c option) */
        uint8_t has_arg;
        /** Offset of field within options structure */
        uint16_t offset;
        /** Parse option
         *
         * @v text              Option text
         * @v value             Option value to fill in
         * @ret rc              Return status code
         */
        int ( * parse ) ( char *text, void *value );
};

/**
 * Construct option parser
 *
 * @v _struct           Options structure type
 * @v _field            Field within options structure
 * @v _parse            Field type-specific option parser
 * @ret _parse          Generic option parser
 */
#define OPTION_PARSER( _struct, _field, _parse )                              \
        ( ( int ( * ) ( char *text, void *value ) )                           \
          ( ( ( ( typeof ( _parse ) * ) NULL ) ==                             \
              ( ( int ( * ) ( char *text,                                     \
                              typeof ( ( ( _struct * ) NULL )->_field ) * ) ) \
                NULL ) ) ? _parse : _parse ) )

/**
 * Construct option descriptor
 *
 * @v _longopt          Long option name, if any
 * @v _shortopt         Short option name, if any
 * @v _has_arg          Argument requirement
 * @v _struct           Options structure type
 * @v _field            Field within options structure
 * @v _parse            Field type-specific option parser
 * @ret _option         Option descriptor
 */
#define OPTION_DESC( _longopt, _shortopt, _has_arg, _struct, _field, _parse ) \
        {                                                                     \
                .longopt = _longopt,                                          \
                .shortopt = _shortopt,                                        \
                .has_arg = _has_arg,                                          \
                .offset = offsetof ( _struct, _field ),                       \
                .parse = OPTION_PARSER ( _struct, _field, _parse ),           \
        }

/** A command descriptor */
struct command_descriptor {
        /** Option descriptors */
        struct option_descriptor *options;
        /** Number of option descriptors */
        uint8_t num_options;
        /** Length of option structure */
        uint8_t len;
        /** Minimum number of non-option arguments */
        uint8_t min_args;
        /** Maximum number of non-option arguments */
        uint8_t max_args;
        /** Command usage
         *
         * This excludes the literal "Usage:" and the command name,
         * which will be prepended automatically.
         */
        const char *usage;
};

/** No maximum number of arguments */
#define MAX_ARGUMENTS 0xff

/**
 * Construct command descriptor
 *
 * @v _struct           Options structure type
 * @v _options          Option descriptor array
 * @v _check_args       Remaining argument checker
 * @v _usage            Command usage
 * @ret _command        Command descriptor
 */
#define COMMAND_DESC( _struct, _options, _min_args, _max_args, _usage )       \
        {                                                                     \
                .options = ( ( ( ( typeof ( _options[0] ) * ) NULL ) ==       \
                               ( ( struct option_descriptor * ) NULL ) ) ?    \
                             _options : _options ),                           \
                .num_options = ( sizeof ( _options ) /                        \
                                 sizeof ( _options[0] ) ),                    \
                .len = sizeof ( _struct ),                                    \
                .min_args = _min_args,                                        \
                .max_args = _max_args,                                        \
                .usage = _usage,                                              \
         }

/** A parsed named setting */
struct named_setting {
        /** Settings block */
        struct settings *settings;
        /** Setting */
        struct setting setting;
};

/** A UUID command-line option */
struct uuid_option {
        /** UUID */
        union uuid *value;
        /** Storage buffer */
        union uuid buf;
};

extern int parse_string ( char *text, char **value );
extern int parse_integer ( char *text, unsigned int *value );
extern int parse_timeout ( char *text, unsigned long *value );
extern int parse_uuid ( char *text, struct uuid_option *uuid );
extern int parse_netdev ( char *text, struct net_device **netdev );
extern int
parse_netdev_configurator ( char *text,
                            struct net_device_configurator **configurator );
extern int parse_menu ( char *text, struct menu **menu );
extern int parse_flag ( char *text __unused, int *flag );
extern int parse_key ( char *text, unsigned int *key );
extern int parse_settings ( char *text, struct settings **settings );
extern int parse_setting ( char *text, struct named_setting *setting,
                           get_child_settings_t get_child );
extern int parse_existing_setting ( char *text, struct named_setting *setting );
extern int parse_autovivified_setting ( char *text,
                                        struct named_setting *setting );
extern int parse_parameters ( char *text, struct parameters **params );
extern void print_usage ( struct command_descriptor *cmd, char **argv );
extern int reparse_options ( int argc, char **argv,
                             struct command_descriptor *cmd, void *opts );
extern int parse_options ( int argc, char **argv,
                           struct command_descriptor *cmd, void *opts );

#endif /* _IPXE_PARSEOPT_H */