1 files changed, 206 insertions, 102 deletions

diff --git a/src/lib/libc/stdlib/getopt.3 b/src/lib/libc/stdlib/getopt.3
index f843881afd..ecdf42ab76 100644
--- a/src/lib/libc/stdlib/getopt.3
+++ b/src/lib/libc/stdlib/getopt.3
@@ -9,11 +9,7 @@
 .\" 2. Redistributions in binary form must reproduce the above copyright
 .\"    notice, this list of conditions and the following disclaimer in the
 .\"    documentation and/or other materials provided with the distribution.
-.\" 3. All advertising materials mentioning features or use of this software
-.\"    must display the following acknowledgement:
-.\"     This product includes software developed by the University of
-.\"     California, Berkeley and its contributors.
-.\" 4. Neither the name of the University nor the names of its contributors
+.\" 3. Neither the name of the University nor the names of its contributors
 .\"    may be used to endorse or promote products derived from this software
 .\"    without specific prior written permission.
 .\"
@@ -29,20 +25,20 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"     @(#)getopt.3    8.4 (Berkeley) 4/19/94
+.\"     $OpenBSD: getopt.3,v 1.42 2011/03/05 22:10:11 guenther Exp $
 .\"
-.Dd April 19, 1994
+.Dd $Mdocdate: March 5 2011 $
 .Dt GETOPT 3
-.Os BSD 4.3
+.Os
 .Sh NAME
 .Nm getopt
 .Nd get option character from command line argument list
 .Sh SYNOPSIS
 .Fd #include <unistd.h>
 .Vt extern char *optarg;
+.Vt extern int   opterr;
 .Vt extern int   optind;
 .Vt extern int   optopt;
-.Vt extern int   opterr;
 .Vt extern int   optreset;
 .Ft int
 .Fn getopt "int argc" "char * const *argv" "const char *optstring"
@@ -61,20 +57,25 @@ if it has been specified in the string of accepted option characters,
 .Pp
 The option string
 .Fa optstring
-may contain the following elements: individual characters, and
-characters followed by a colon to indicate an option argument
-is to follow.
+may contain the following elements: individual characters,
+characters followed by a colon, and characters followed by two colons.
+A character followed by a single colon indicates that an argument
+is to follow the option on the command line.
+Two colons indicates that the argument is optional \- this is an
+extension not covered by POSIX.
 For example, an option string
-.Li "\&""x""
+.Qq x
 recognizes an option
-.Dq Fl x ,
+.Fl x ,
 and an option string
-.Li "\&""x:""
+.Qq Li x:
 recognizes an option and argument
-.Dq Fl x Ar argument .
+.Fl x Ar argument .
 It does not matter to
 .Fn getopt
-if a following argument has leading white space.
+if a following argument has leading whitespace; except in the case where
+the argument is optional, denoted with two colons, no leading whitespace
+is permitted.
 .Pp
 On return from
 .Fn getopt ,
@@ -87,23 +88,23 @@ contains the index to the next
 argument for a subsequent call
 to
 .Fn getopt .
-The variable
-.Va optopt
-saves the last
-.Em known
-option character returned by
-.Fn getopt .
 .Pp
-The variable
+The variables
 .Va opterr
 and
 .Va optind
 are both initialized to 1.
 The
 .Va optind
-variable may be set to another value before a set of calls to
+variable may be set to another value larger than 0 before a set of calls to
 .Fn getopt
-in order to skip over more or less argv entries.
+in order to skip over more or less
+.Fa argv
+entries.
+An
+.Va optind
+value of 0 is reserved for compatibility with GNU
+.Fn getopt .
 .Pp
 In order to use
 .Fn getopt
@@ -119,101 +120,154 @@ must be reinitialized.
 .Pp
 The
 .Fn getopt
-function
-returns \-1
-when the argument list is exhausted, or a non-recognized
-option is encountered.
+function returns \-1 when the argument list is exhausted.
 The interpretation of options in the argument list may be cancelled
 by the option
 .Ql --
 (double dash) which causes
 .Fn getopt
-to signal the end of argument processing and returns \-1.
+to signal the end of argument processing and return \-1.
 When all options have been processed (i.e., up to the first non-option
 argument),
 .Fn getopt
 returns \-1.
-.Sh DIAGNOSTICS
-If the
+.Sh RETURN VALUES
+The
 .Fn getopt
-function encounters a character not found in the string
-.Va optarg
-or detects
-a missing option argument it writes an error message and returns
-.Ql ?
-to the
-.Em stderr .
-Setting
-.Va opterr
-to a zero will disable these error messages.
+function returns the next known option character in
+.Fa optstring .
 If
-.Va optstring 
-has a leading 
-.Ql \&:
-then a missing option argument causes a
-.Ql \&:
-to be returned in addition to suppressing any error messages.
-.Pp
-Option arguments are allowed to begin with
-.Dq Li \- ;
-this is reasonable but
-reduces the amount of error checking possible.
-.Sh EXTENSIONS
+.Fn getopt
+encounters a character not found in
+.Fa optstring
+or if it detects a missing option argument,
+it returns
+.Sq \&?
+(question mark).
+If
+.Fa optstring
+has a leading
+.Sq \&:
+then a missing option argument causes
+.Sq \&:
+to be returned instead of
+.Sq \&? .
+In either case, the variable
+.Va optopt
+is set to the character that caused the error.
 The
-.Va optreset
-variable was added to make it possible to call the
 .Fn getopt
-function multiple times.
-This is an extension to the
-.St -p1003.2
-specification.
-.Sh EXAMPLE
-.Bd -literal -compact
-extern char *optarg;
-extern int optind;
+function returns \-1 when the argument list is exhausted.
+.Sh EXAMPLES
+The following code accepts the options
+.Fl b
+and
+.Fl f Ar argument
+and adjusts
+.Va argc
+and
+.Va argv
+after option argument processing has completed.
+.Bd -literal -offset indent
 int bflag, ch, fd;
 
 bflag = 0;
-while ((ch = getopt(argc, argv, "bf:")) != -1)
-        switch(ch) {
+while ((ch = getopt(argc, argv, "bf:")) != -1) {
+        switch (ch) {
         case 'b':
                 bflag = 1;
                 break;
         case 'f':
-                if ((fd = open(optarg, O_RDONLY, 0)) < 0) {
-                        (void)fprintf(stderr,
-                            "myname: %s: %s\en", optarg, strerror(errno));
-                        exit(1);
-                }
+                if ((fd = open(optarg, O_RDONLY, 0)) == -1)
+                        err(1, "%s", optarg);
                 break;
-        case '?':
         default:
                 usage();
+                /* NOTREACHED */
+        }
 }
 argc -= optind;
 argv += optind;
 .Ed
-.Sh HISTORY
+.Sh DIAGNOSTICS
+If the
+.Fn getopt
+function encounters a character not found in the string
+.Fa optstring
+or detects
+a missing option argument, it writes an error message to
+.Em stderr
+and returns
+.Ql \&? .
+Setting
+.Va opterr
+to a zero will disable these error messages.
+If
+.Fa optstring
+has a leading
+.Ql \&:
+then a missing option argument causes a
+.Ql \&:
+to be returned in addition to suppressing any error messages.
+.Pp
+Option arguments are allowed to begin with
+.Ql - ;
+this is reasonable but reduces the amount of error checking possible.
+.Sh SEE ALSO
+.Xr getopt 1 ,
+.Xr getopt_long 3 ,
+.Xr getsubopt 3
+.Sh STANDARDS
 The
 .Fn getopt
-function appeared
-.Bx 4.3 .
-.Sh BUGS
+function implements a superset of the functionality specified by
+.St -p1003.1 .
+.Pp
+The following extensions are supported:
+.Bl -tag -width "xxx"
+.It Li o
 The
+.Va optreset
+variable was added to make it possible to call the
 .Fn getopt
-function was once specified to return
-.Dv EOF 
-instead of \-1.
-This was changed by
-.St -p1003.2-92
-to decouple 
+function multiple times.
+.It Li o
+If the
+.Va optind
+variable is set to 0,
 .Fn getopt
-from 
-.Pa <stdio.h> .
-.Pp
+will behave as if the
+.Va optreset
+variable has been set.
+This is for compatibility with
+.Tn GNU
+.Fn getopt .
+New code should use
+.Va optreset
+instead.
+.It Li o
+If the first character of
+.Fa optstring
+is a plus sign
+.Pq Ql + ,
+it will be ignored.
+This is for compatibility with
+.Tn GNU
+.Fn getopt .
+.It Li o
+If the first character of
+.Fa optstring
+is a dash
+.Pq Ql - ,
+non-options will be returned as arguments to the option character
+.Ql \e1 .
+This is for compatibility with
+.Tn GNU
+.Fn getopt .
+.It Li o
 A single dash
-.Dq Li -
-may be specified as an character in
+.Pq Ql -
+may be specified as a character in
 .Fa optstring ,
 however it should
 .Em never
@@ -221,40 +275,90 @@ have an argument associated with it.
 This allows
 .Fn getopt
 to be used with programs that expect
-.Dq Li -
+.Ql -
 as an option flag.
 This practice is wrong, and should not be used in any current development.
 It is provided for backward compatibility
 .Em only .
+Care should be taken not to use
+.Ql -
+as the first character in
+.Fa optstring
+to avoid a semantic conflict with
+.Tn GNU
+.Fn getopt
+semantics (see above).
 By default, a single dash causes
 .Fn getopt
 to return \-1.
-This is, we believe, compatible with System V.
+.El
+.Pp
+Historic
+.Bx
+versions of
+.Fn getopt
+set
+.Fa optopt
+to the last option character processed.
+However, this conflicts with
+.St -p1003.1
+which stipulates that
+.Fa optopt
+be set to the last character that caused an error.
+.Sh HISTORY
+The
+.Fn getopt
+function appeared in
+.Bx 4.3 .
+.Sh BUGS
+The
+.Fn getopt
+function was once specified to return
+.Dv EOF
+instead of \-1.
+This was changed by
+.St -p1003.2-92
+to decouple
+.Fn getopt
+from
+.Aq Pa stdio.h .
 .Pp
-It is also possible to handle digits as option letters.
+It is possible to handle digits as option letters.
 This allows
 .Fn getopt
 to be used with programs that expect a number
-.Pq Dq Li \&-\&3
+.Pq Dq Li \-3
 as an option.
 This practice is wrong, and should not be used in any current development.
 It is provided for backward compatibility
 .Em only .
-The following code fragment works in most cases.
+The following code fragment works in most cases and can handle mixed
+number and letter arguments.
 .Bd -literal -offset indent
-int length;
-char *p;
+int aflag = 0, bflag = 0, ch, lastch = '\e0';
+int length = -1, newarg = 1, prevoptind = 1;
 
-while ((c = getopt(argc, argv, "0123456789")) != -1)
-        switch (c) {
+while ((ch = getopt(argc, argv, "0123456789ab")) != -1) {
+        switch (ch) {
         case '0': case '1': case '2': case '3': case '4':
         case '5': case '6': case '7': case '8': case '9':
-                p = argv[optind - 1];
-                if (p[0] == '-' && p[1] == ch && !p[2])
-                        length = atoi(++p);
-                else
-                        length = atoi(argv[optind] + 1);
+                if (newarg || !isdigit(lastch))
+                        length = 0;
+                else if (length > INT_MAX / 10)
+                        usage();
+                length = (length * 10) + (ch - '0');
                 break;
+        case 'a':
+                aflag = 1;
+                break;
+        case 'b':
+                bflag = 1;
+                break;
+        default:
+                usage();
         }
+        lastch = ch;
+        newarg = optind != prevoptind;
+        prevoptind = optind;
 }
 .Ed