glibc/manual/examples/argp-ex4.c

145 lines
4.0 KiB
C

/* Argp example #4 -- a program with somewhat more complicated options */
#include <stdlib.h>
#include <error.h>
#include <argp.h>
const char *argp_program_version =
"argp-ex4 1.0";
const char *argp_program_bug_address =
"<bug-gnu-utils@@prep.ai.mit.edu>";
/* Program documentation. */
static char doc[] =
"Argp example #4 -- a program with somewhat more complicated\
options\
\vThis part of the documentation comes *after* the options;\
note that the text is automatically filled, but it's possible\
to force a line-break, e.g.\n<-- here.";
/* A description of the arguments we accept. */
static char args_doc[] = "ARG1 [STRING...]";
/* Keys for options without short-options. */
#define OPT_ABORT 1 /* --abort */
/* The options we understand. */
static struct argp_option options[] = {
{"verbose", 'v', 0, 0, "Produce verbose output" },
{"quiet", 'q', 0, 0, "Don't produce any output" },
{"silent", 's', 0, OPTION_ALIAS },
{"output", 'o', "FILE", 0,
"Output to FILE instead of standard output" },
{0,0,0,0, "The following options should be grouped together:" },
{"repeat", 'r', "COUNT", OPTION_ARG_OPTIONAL,
"Repeat the output COUNT (default 10) times"},
{"abort", OPT_ABORT, 0, 0, "Abort before showing any output"},
{ 0 }
};
/* Used by @code{main} to communicate with @code{parse_opt}. */
struct arguments
{
char *arg1; /* @var{arg1} */
char **strings; /* [@var{string}@dots{}] */
int silent, verbose, abort; /* @samp{-s}, @samp{-v}, @samp{--abort} */
char *output_file; /* @var{file} arg to @samp{--output} */
int repeat_count; /* @var{count} arg to @samp{--repeat} */
};
/* Parse a single option. */
static error_t
parse_opt (int key, char *arg, struct argp_state *state)
{
/* Get the @code{input} argument from @code{argp_parse}, which we
know is a pointer to our arguments structure. */
struct arguments *arguments = state->input;
switch (key)
{
case 'q': case 's':
arguments->silent = 1;
break;
case 'v':
arguments->verbose = 1;
break;
case 'o':
arguments->output_file = arg;
break;
case 'r':
arguments->repeat_count = arg ? atoi (arg) : 10;
break;
case OPT_ABORT:
arguments->abort = 1;
break;
case ARGP_KEY_NO_ARGS:
argp_usage (state);
case ARGP_KEY_ARG:
/* Here we know that @code{state->arg_num == 0}, since we
force argument parsing to end before any more arguments can
get here. */
arguments->arg1 = arg;
/* Now we consume all the rest of the arguments.
@code{state->next} is the index in @code{state->argv} of the
next argument to be parsed, which is the first @var{string}
we're interested in, so we can just use
@code{&state->argv[state->next]} as the value for
arguments->strings.
@emph{In addition}, by setting @code{state->next} to the end
of the arguments, we can force argp to stop parsing here and
return. */
arguments->strings = &state->argv[state->next];
state->next = state->argc;
break;
default:
return ARGP_ERR_UNKNOWN;
}
return 0;
}
/* Our argp parser. */
static struct argp argp = { options, parse_opt, args_doc, doc };
int main (int argc, char **argv)
{
int i, j;
struct arguments arguments;
/* Default values. */
arguments.silent = 0;
arguments.verbose = 0;
arguments.output_file = "-";
arguments.repeat_count = 1;
arguments.abort = 0;
/* Parse our arguments; every option seen by @code{parse_opt} will be
reflected in @code{arguments}. */
argp_parse (&argp, argc, argv, 0, 0, &arguments);
if (arguments.abort)
error (10, 0, "ABORTED");
for (i = 0; i < arguments.repeat_count; i++)
{
printf ("ARG1 = %s\n", arguments.arg1);
printf ("STRINGS = ");
for (j = 0; arguments.strings[j]; j++)
printf (j == 0 ? "%s" : ", %s", arguments.strings[j]);
printf ("\n");
printf ("OUTPUT_FILE = %s\nVERBOSE = %s\nSILENT = %s\n",
arguments.output_file,
arguments.verbose ? "yes" : "no",
arguments.silent ? "yes" : "no");
}
exit (0);
}