From 675605958e27abb48f9fb925a91376d61a3f7637 Mon Sep 17 00:00:00 2001
From: Peter Avalos <pavalos@dragonflybsd.org>
Date: Sun, 14 Jan 2007 04:41:32 +0000
Subject: [PATCH] Include disabled options in the output of 'set +o'.  POSIX
 says the output of set +o can be used to reload previous settings, for this
 to work disabled options must be printed as well or otherwise options that
 were set in the mean time won't be turned off.

Change /bin/sh so *it* implements the processing needed for scripts to
work as expected when they have a "shebang line" of:

     #!/bin/sh -- # -*- perl -*- -p

Obtained-from:  FreeBSD
---
 bin/sh/options.c | 96 ++++++++++++++++++++++++++++++++++++------------
 1 file changed, 72 insertions(+), 24 deletions(-)

diff --git a/bin/sh/options.c b/bin/sh/options.c
index 9b88b4a8ae..82d3c19aa3 100644
--- a/bin/sh/options.c
+++ b/bin/sh/options.c
@@ -34,8 +34,8 @@
  * SUCH DAMAGE.
  *
  * @(#)options.c	8.2 (Berkeley) 5/4/95
- * $FreeBSD: src/bin/sh/options.c,v 1.15.2.2 2002/07/19 04:38:52 tjr Exp $
- * $DragonFly: src/bin/sh/options.c,v 1.6 2007/01/07 01:14:53 pavalos Exp $
+ * $FreeBSD: src/bin/sh/options.c,v 1.25 2006/04/09 12:20:42 stefanf Exp $
+ * $DragonFly: src/bin/sh/options.c,v 1.7 2007/01/14 04:41:32 pavalos Exp $
  */
 
 #include <signal.h>
@@ -138,7 +138,7 @@ optschanged(void)
 STATIC void
 options(int cmdline)
 {
-	char *p;
+	char *kp, *p;
 	int val;
 	int c;
 
@@ -148,16 +148,29 @@ options(int cmdline)
 		argptr++;
 		if ((c = *p++) == '-') {
 			val = 1;
-                        if (p[0] == '\0' || (p[0] == '-' && p[1] == '\0')) {
-                                if (!cmdline) {
-                                        /* "-" means turn off -x and -v */
-                                        if (p[0] == '\0')
-                                                xflag = vflag = 0;
-                                        /* "--" means reset params */
-                                        else if (*argptr == NULL)
-						setparam(argptr);
-                                }
-				break;	  /* "-" or  "--" terminates options */
+			/* A "-" or  "--" terminates options */
+			if (p[0] == '\0')
+				goto end_options1;
+			if (p[0] == '-' && p[1] == '\0')
+				goto end_options2;
+			/**
+			 * For the benefit of `#!' lines in shell scripts,
+			 * treat a string of '-- *#.*' the same as '--'.
+			 * This is needed so that a script starting with:
+			 *	#!/bin/sh -- # -*- perl -*-
+			 * will continue to work after a change is made to
+			 * kern/imgact_shell.c to NOT token-ize the options
+			 * specified on a '#!' line.  A bit of a kludge,
+			 * but that trick is recommended in documentation
+			 * for some scripting languages, and we might as
+			 * well continue to support it.
+			 */
+			if (p[0] == '-') {
+				kp = p + 1;
+				while (*kp == ' ' || *kp == '\t')
+					kp++;
+				if (*kp == '#' || *kp == '\0')
+					goto end_options2;
 			}
 		} else if (c == '+') {
 			val = 0;
@@ -191,12 +204,50 @@ options(int cmdline)
 			}
 		}
 	}
+	return;
+
+	/* When processing `set', a single "-" means turn off -x and -v */
+end_options1:
+	if (!cmdline) {
+		xflag = vflag = 0;
+		return;
+	}
+
+	/*
+	 * When processing `set', a "--" means the remaining arguments
+	 * replace the positional parameters in the active shell.  If
+	 * there are no remaining options, then all the positional
+	 * parameters are cleared (equivalent to doing ``shift $#'').
+	 */
+end_options2:
+	if (!cmdline) {
+		if (*argptr == NULL)
+			setparam(argptr);
+		return;
+	}
+
+	/*
+	 * At this point we are processing options given to 'sh' on a command
+	 * line.  If an end-of-options marker ("-" or "--") is followed by an
+	 * arg of "#", then skip over all remaining arguments.  Some scripting
+	 * languages (e.g.: perl) document that /bin/sh will implement this
+	 * behavior, and they recommend that users take advantage of it to
+	 * solve certain issues that can come up when writing a perl script.
+	 * Yes, this feature is in /bin/sh to help users write perl scripts.
+	 */
+	p = *argptr;
+	if (p != NULL && p[0] == '#' && p[1] == '\0') {
+		while (*argptr != NULL)
+			argptr++;
+		/* We need to keep the final argument */
+		argptr--;
+	}
 }
 
 STATIC void
 minus_o(char *name, int val)
 {
-	int doneset, i;
+	int i;
 
 	if (name == NULL) {
 		if (val) {
@@ -207,16 +258,13 @@ minus_o(char *name, int val)
 					optlist[i].val ? "on" : "off");
 		} else {
 			/* Output suitable for re-input to shell. */
-			for (doneset = i = 0; i < NOPTS; i++)
-				if (optlist[i].val) {
-					if (!doneset) {
-						out1str("set");
-						doneset = 1;
-					}
-					out1fmt(" -o %s", optlist[i].name);
-				}
-			if (doneset)
-				out1c('\n');
+			for (i = 0; i < NOPTS; i++) {
+				if (i % 6 == 0)
+					out1str(i == 0 ? "set" : "\nset");
+				out1fmt(" %co %s", optlist[i].val ? '-' : '+',
+					optlist[i].name);
+			}
+			out1c('\n');
 		}
 	} else {
 		for (i = 0; i < NOPTS; i++)
-- 
2.41.0