getopt: simple code shrink; expand help text

[platform/upstream/busybox.git] / util-linux / getopt.c

diff --git a/util-linux/getopt.c b/util-linux/getopt.c
index c45edf8..6bad3ef 100644 (file)
--- a/util-linux/getopt.c
+++ b/util-linux/getopt.c
@@ -32,30 +32,48 @@
  */
 
 //usage:#define getopt_trivial_usage
-//usage:       "[OPTIONS]"
+//usage:       "[OPTIONS] [--] OPTSTRING PARAMS"
 //usage:#define getopt_full_usage "\n\n"
 //usage:       IF_LONG_OPTS(
 //usage:       "       -a,--alternative                Allow long options starting with single -"
-//usage:     "\n       -l,--longoptions=longopts       Long options to be recognized"
-//usage:     "\n       -n,--name=progname              The name under which errors are reported"
-//usage:     "\n       -o,--options=optstring          Short options to be recognized"
+//usage:     "\n       -l,--longoptions=LOPT[,...]     Long options to be recognized"
+//usage:     "\n       -n,--name=PROGNAME              The name under which errors are reported"
+//usage:     "\n       -o,--options=OPTSTRING          Short options to be recognized"
 //usage:     "\n       -q,--quiet                      Disable error reporting by getopt(3)"
 //usage:     "\n       -Q,--quiet-output               No normal output"
-//usage:     "\n       -s,--shell=shell                Set shell quoting conventions"
+//usage:     "\n       -s,--shell=SHELL                Set shell quoting conventions"
 //usage:     "\n       -T,--test                       Test for getopt(1) version"
 //usage:     "\n       -u,--unquoted                   Don't quote the output"
 //usage:       )
 //usage:       IF_NOT_LONG_OPTS(
 //usage:       "       -a              Allow long options starting with single -"
-//usage:     "\n       -l longopts     Long options to be recognized"
-//usage:     "\n       -n progname     The name under which errors are reported"
-//usage:     "\n       -o optstring    Short options to be recognized"
+//usage:     "\n       -l LOPT[,...]   Long options to be recognized"
+//usage:     "\n       -n PROGNAME     The name under which errors are reported"
+//usage:     "\n       -o OPTSTRING    Short options to be recognized"
 //usage:     "\n       -q              Disable error reporting by getopt(3)"
 //usage:     "\n       -Q              No normal output"
-//usage:     "\n       -s shell        Set shell quoting conventions"
+//usage:     "\n       -s SHELL        Set shell quoting conventions"
 //usage:     "\n       -T              Test for getopt(1) version"
 //usage:     "\n       -u              Don't quote the output"
 //usage:       )
+//usage:     "\n"
+//usage:     "\nExample:"
+//usage:     "\n"
+//usage:     "\nO=`getopt -l bb: -- ab:c:: \"$@\"`"
+//usage:     "\n[ $? = 0 ] || exit 1"
+//usage:     "\neval set -- \"$O\""
+//usage:     "\nwhile true; do"
+//usage:     "\n       case \"$1\" in"
+//usage:     "\n       -a)     echo A; shift;;"
+//usage:     "\n       -b|--bb) echo \"B:'$2'\"; shift 2;;"
+//usage:     "\n       -c)     case \"$2\" in"
+//usage:     "\n               \"\")   echo C; shift 2;;"
+//usage:     "\n               *)      echo \"C:'$2'\"; shift 2;;"
+//usage:     "\n               esac;;"
+//usage:     "\n       --)     shift; break;;"
+//usage:     "\n       *)      echo Error; exit 1;;"
+//usage:     "\n       esac"
+//usage:     "\ndone"
 //usage:
 //usage:#define getopt_example_usage
 //usage:       "$ cat getopt.test\n"
@@ -339,6 +357,7 @@ static const char getopt_longopts[] ALIGN1 =
 int getopt_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int getopt_main(int argc, char **argv)
 {
+       int n;
        char *optstr = NULL;
        char *name = NULL;
        unsigned opt;
@@ -351,7 +370,7 @@ int getopt_main(int argc, char **argv)
 
        compatible = getenv("GETOPT_COMPATIBLE"); /* used as yes/no flag */
 
-       if (argc == 1) {
+       if (!argv[1]) {
                if (compatible) {
                        /* For some reason, the original getopt gave no error
                           when there were no arguments. */
@@ -362,10 +381,10 @@ int getopt_main(int argc, char **argv)
        }
 
        if (argv[1][0] != '-' || compatible) {
-               char *s;
+               char *s = argv[1];
 
                option_mask32 |= OPT_u; /* quoting off */
-               s = xstrdup(argv[1] + strspn(argv[1], "-+"));
+               s = xstrdup(s + strspn(s, "-+"));
                argv[1] = argv[0];
                return generate_output(argv+1, argc-1, s, long_options);
        }
@@ -392,12 +411,13 @@ int getopt_main(int argc, char **argv)
        }
 
        /* All options controlling the applet have now been parsed */
+       n = optind - 1;
        if (!optstr) {
-               if (optind >= argc)
+               optstr = argv[++n];
+               if (!optstr)
                        bb_error_msg_and_die("missing optstring argument");
-               optstr = argv[optind++];
        }
 
-       argv[optind-1] = name ? name : argv[0];
-       return generate_output(argv+optind-1, argc-optind+1, optstr, long_options);
+       argv[n] = name ? name : argv[0];
+       return generate_output(argv + n, argc - n, optstr, long_options);
 }