getopt.c File Reference

Parse command-line options. More...

#include <stdint.h>
#include <string.h>
#include <stdio.h>
#include <getopt.h>

Go to the source code of this file.

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
static const char *	get_argv_argument (int argc, char *const argv[])
	Get option argument from argv[] array. More...
static int	match_long_option (int argc, char *const argv[], const char *opttext, const struct option *longopt, int *option)
	Match long option. More...
static int	match_short_option (int argc, char *const argv[], const char *opttext, int shortopt, enum getopt_argument_requirement has_arg, int *option)
	Match short option. More...
int	getopt_long (int argc, char *const argv[], const char *optstring, const struct option *longopts, int *longindex)
	Parse command-line options. More...

Variables
char *	optarg
	Option argument. More...
int	optind
	Current option index. More...
int	nextchar
	Current option character index. More...
int	optopt
	Unrecognised option. More...

Detailed Description

Parse command-line options.

Definition in file getopt.c.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

get_argv_argument()

static const char* get_argv_argument ( int  argc, char *const  argv[]  )

static

Get option argument from argv[] array.

Parameters

argc	Argument count
argv	Argument list

Return values

argument

Option argument, or NULL

Grab the next element of argv[], if it exists and is not an option.

Consume this argv element, and return it

Definition at line 77 of file getopt.c.

                                                                        {
        char *arg;

        /* Don't overrun argv[] */
        if ( optind >= argc )
                return NULL;
        arg = argv[optind];

        /* If next argv element is an option, then it's not usable as
         * an argument.
         */
        if ( *arg == '-' )
                return NULL;

        /** Consume this argv element, and return it */
        optind++;
        return arg;
}

References NULL, and optind.

Referenced by match_long_option(), and match_short_option().

match_long_option()

static int match_long_option ( int  argc, char *const  argv[], const char *  opttext, const struct option *  longopt, int *  option  )

static

Match long option.

Parameters

argc	Argument count
argv	Argument list
opttext	Option text within current argv[] element
longopt	Long option specification

Return values

option	Option to return from getopt()
matched	Found a match for this long option

Definition at line 106 of file getopt.c.

                                                                           {
        size_t optlen;
        const char *argument = NULL;

        /* Compare option name */
        optlen = strlen ( longopt->name );
        if ( strncmp ( opttext, longopt->name, optlen ) != 0 )
                return 0;

        /* Check for inline argument */
        if ( opttext[optlen] == '=' ) {
                argument = &opttext[ optlen + 1 ];
        } else if ( opttext[optlen] ) {
                /* Long option with trailing garbage - no match */
                return 0;
        }

        /* Consume this argv element */
        optind++;

        /* If we want an argument but don't have one yet, try to grab
         * the next argv element
         */
        if ( ( longopt->has_arg != no_argument ) && ( ! argument ) )
                argument = get_argv_argument ( argc, argv );

        /* If we need an argument but don't have one, sulk */
        if ( ( longopt->has_arg == required_argument ) && ( ! argument ) ) {
                printf ( "Option \"%s\" requires an argument\n",
                         longopt->name );
                *option = ':';
                return 1;
        }

        /* If we have an argument where we shouldn't have one, sulk */
        if ( ( longopt->has_arg == no_argument ) && argument ) {
                printf ( "Option \"%s\" takes no argument\n", longopt->name );
                *option = ':';
                return 1;
        }

        /* Store values and return success */
        optarg = ( char * ) argument;
        if ( longopt->flag ) {
                *(longopt->flag) = longopt->val;
                *option = 0;
        } else {
                *option = longopt->val;
        }
        return 1;
}

References option::flag, get_argv_argument(), option::has_arg, option::name, no_argument, NULL, optarg, optind, printf(), required_argument, strlen(), strncmp(), and option::val.

Referenced by getopt_long().

match_short_option()

static int match_short_option ( int  argc, char *const  argv[], const char *  opttext, int  shortopt, enum getopt_argument_requirement  has_arg, int *  option  )

static

Match short option.

Parameters

argc	Argument count
argv	Argument list
opttext	Option text within current argv[] element
shortopt	Option character from option specification

Return values

option	Option to return from getopt()
matched	Found a match for this short option

Definition at line 170 of file getopt.c.

                                              {
        const char *argument = NULL;

        /* Compare option character */
        if ( *opttext != shortopt )
                return 0;

        /* Consume option character */
        opttext++;
        nextchar++;
        if ( *opttext ) {
                if ( has_arg != no_argument ) {
                        /* Consume remainder of element as inline argument */
                        argument = opttext;
                        optind++;
                        nextchar = 0;
                }
        } else {
                /* Reached end of argv element */
                optind++;
                nextchar = 0;
        }

        /* If we want an argument but don't have one yet, try to grab
         * the next argv element
         */
        if ( ( has_arg != no_argument ) && ( ! argument ) )
                argument = get_argv_argument ( argc, argv );

        /* If we need an argument but don't have one, sulk */
        if ( ( has_arg == required_argument ) && ( ! argument ) ) {
                printf ( "Option \"%c\" requires an argument\n", shortopt );
                *option = ':';
                return 1;
        }

        /* Store values and return success */
        optarg = ( char * ) argument;
        *option = shortopt;
        return 1;
}

References get_argv_argument(), nextchar, no_argument, NULL, optarg, optind, printf(), and required_argument.

Referenced by getopt_long().

getopt_long()

int getopt_long	(	int	argc,
		char *const	argv[],
		const char *	optstring,
		const struct option *	longopts,
		int *	longindex
	)

Parse command-line options.

Parameters

argc	Argument count
argv	Argument list
optstring	Option specification string
longopts	Long option specification table

Return values

longindex	Index of long option (or NULL)
option	Option found, or -1 for no more options

Note that the caller must arrange for reset_getopt() to be called before each set of calls to getopt_long(). In Etherboot, this is done automatically by execv().

Definition at line 229 of file getopt.c.

                                                                  {
        const char *opttext = argv[optind];
        const struct option *longopt;
        int shortopt;
        enum getopt_argument_requirement has_arg;
        int option;

        /* Check for end of argv array */
        if ( optind >= argc )
                return -1;

        /* Check for end of options */
        if ( *(opttext++) != '-' )
                return -1;

        /* Check for long options */
        if ( *(opttext++) == '-' ) {
                /* "--" indicates end of options */
                if ( *opttext == '\0' ) {
                        optind++;
                        return -1;
                }
                for ( longopt = longopts ; longopt->name ; longopt++ ) {
                        if ( ! match_long_option ( argc, argv, opttext,
                                                   longopt, &option ) )
                                continue;
                        if ( longindex )
                                *longindex = ( longopt - longopts );
                        return option;
                }
                optopt = '?';
                printf ( "Unrecognised option \"--%s\"\n", opttext );
                return '?';
        }

        /* Check for short options */
        if ( nextchar < 1 )
                nextchar = 1;
        opttext = ( argv[optind] + nextchar );
        while ( ( shortopt = *(optstring++) ) ) {
                has_arg = no_argument;
                while ( *optstring == ':' ) {
                        has_arg++;
                        optstring++;
                }
                if ( match_short_option ( argc, argv, opttext, shortopt,
                                          has_arg, &option ) ) {
                        return option;
                }
        }
        optopt = *opttext;
        printf ( "Unrecognised option \"-%c\"\n", optopt );
        return '?';
}

References option::has_arg, match_long_option(), match_short_option(), option::name, nextchar, no_argument, optind, optopt, and printf().

Referenced by getopt(), linux_args_parse(), and reparse_options().

Variable Documentation

optarg

char* optarg

Option argument.

This will point to the argument for the most recently returned option, if applicable.

Definition at line 43 of file getopt.c.

Referenced by linux_args_parse(), match_long_option(), match_short_option(), and reparse_options().

optind

int optind

Current option index.

This is an index into the argv[] array. When getopt() returns -1, optind is the index to the first element that is not an option.

Definition at line 51 of file getopt.c.

Referenced by cert_exec(), choose_exec(), colour_exec(), config_exec(), cpair_exec(), cpuid_exec(), digest_exec(), echo_exec(), exit_exec(), fcels_exec(), gdbstub_exec(), get_argv_argument(), getopt_long(), goto_exec(), ifcommon_exec(), imgextract_exec(), imgmem_exec(), imgmulti_exec(), imgsingle_exec(), imgverify_exec(), inc_exec(), iseq_exec(), isset_exec(), item_exec(), lotest_exec(), match_long_option(), match_short_option(), menu_exec(), nslookup_exec(), ntp_exec(), param_exec(), pciscan_exec(), ping_exec(), prompt_exec(), pxebs_exec(), reparse_options(), reset_getopt(), sanboot_core_exec(), set_core_exec(), shim_exec(), show_exec(), sleep_exec(), vcreate_exec(), and vdestroy_exec().

nextchar

int nextchar

Current option character index.

This is an index into the current element of argv[].

Definition at line 58 of file getopt.c.

Referenced by getopt_long(), match_short_option(), and reset_getopt().

optopt

int optopt

Unrecognised option.

When an unrecognised option is encountered, the actual option character is stored in optopt.

Definition at line 66 of file getopt.c.

Referenced by getopt_long().