Fix most “set -x” problems (LP#1179287)

• “set -x” manually (cmdline too) snapshots fd#2 now
• “set -o inherit-xtrace” introduced; default still enabled
• reverted iodup printing to pre-R45 behaviour
• made Flag(FXTRACE) a proper state machine

Build.sh

@@ -1,5 +1,5 @@
 #!/bin/sh
-srcversion='$MirOS: src/bin/mksh/Build.sh,v 1.639 2013/07/08 10:12:45 tg Exp $'
+srcversion='$MirOS: src/bin/mksh/Build.sh,v 1.640 2013/07/21 18:47:14 tg Exp $'
 #-
 # Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
 #		2011, 2012, 2013
@@ -1544,7 +1544,7 @@ else
 		#define EXTERN
 		#define MKSH_INCLUDES_ONLY
 		#include "sh.h"
-		__RCSID("$MirOS: src/bin/mksh/Build.sh,v 1.639 2013/07/08 10:12:45 tg Exp $");
+		__RCSID("$MirOS: src/bin/mksh/Build.sh,v 1.640 2013/07/21 18:47:14 tg Exp $");
 		int main(void) { printf("Hello, World!\n"); return (0); }
 EOF
 	case $cm in
@@ -2059,7 +2059,7 @@ addsrcs USE_PRINTF_BUILTIN printf.c
 test 1 = "$USE_PRINTF_BUILTIN" && add_cppflags -DMKSH_PRINTF_BUILTIN
 test 1 = "$HAVE_CAN_VERB" && CFLAGS="$CFLAGS -verbose"
 test -n "$LDSTATIC" && add_cppflags -DMKSH_OPTSTATIC
-add_cppflags -DMKSH_BUILD_R=469
+add_cppflags -DMKSH_BUILD_R=471
 
 $e $bi$me: Finished configuration testing, now producing output.$ao
 

Makefile

@@ -1,4 +1,4 @@
-# $MirOS: src/bin/mksh/Makefile,v 1.122 2013/05/31 23:27:13 tg Exp $
+# $MirOS: src/bin/mksh/Makefile,v 1.123 2013/07/21 18:47:15 tg Exp $
 #-
 # Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
 #		2011, 2012, 2013
@@ -54,7 +54,7 @@ CPPFLAGS+=	-DMKSH_ASSUME_UTF8 -DMKSH_DISABLE_DEPRECATED \
 		-DHAVE_SETGROUPS=1 -DHAVE_STRERROR=0 -DHAVE_STRSIGNAL=0 \
 		-DHAVE_STRLCPY=1 -DHAVE_FLOCK_DECL=1 -DHAVE_REVOKE_DECL=1 \
 		-DHAVE_SYS_ERRLIST_DECL=1 -DHAVE_SYS_SIGLIST_DECL=1 \
-		-DHAVE_PERSISTENT_HISTORY=1 -DMKSH_BUILD_R=469
+		-DHAVE_PERSISTENT_HISTORY=1 -DMKSH_BUILD_R=471
 CPPFLAGS+=	-D${${PROG:L}_tf:C/(Mir${MAN:E}{0,1}){2}/4/:S/x/mksh_BUILD/:U}
 COPTS+=		-std=c99 -Wall
 .endif

check.t

@@ -1,4 +1,4 @@
-# $MirOS: src/bin/mksh/check.t,v 1.618 2013/07/21 18:38:53 tg Exp $
+# $MirOS: src/bin/mksh/check.t,v 1.619 2013/07/21 18:47:16 tg Exp $
 # $OpenBSD: bksl-nl.t,v 1.2 2001/01/28 23:04:56 niklas Exp $
 # $OpenBSD: history.t,v 1.5 2001/01/28 23:04:56 niklas Exp $
 # $OpenBSD: read.t,v 1.3 2003/03/10 03:48:16 david Exp $
@@ -31,7 +31,7 @@
 # http://www.freebsd.org/cgi/cvsweb.cgi/src/tools/regression/bin/test/regress.sh?rev=HEAD
 
 expected-stdout:
-	@(#)MIRBSD KSH R46 2013/06/03
+	@(#)MIRBSD KSH R47 2013/07/21
 description:
 	Check version of shell.
 stdin:
@@ -40,7 +40,7 @@ name: KSH_VERSION
 category: shell:legacy-no
 ---
 expected-stdout:
-	@(#)LEGACY KSH R46 2013/06/03
+	@(#)LEGACY KSH R47 2013/07/21
 description:
 	Check version of legacy shell.
 stdin:
@@ -11107,3 +11107,19 @@ stdin:
 	done
 	Lb64decode $s >/dev/null
 ---
+name: xtrace-1
+description:
+	Check that "set -x" doesn't redirect too quickly
+stdin:
+	print '#!'"$__progname" >bash
+	cat >>bash <<'EOF'
+	echo 'GNU bash, version 2.05b.0(1)-release (i386-ecce-mirbsd10)
+	Copyright (C) 2002 Free Software Foundation, Inc.'
+	EOF
+	chmod +x bash
+	"$__progname" -xc 'foo=$(./bash --version 2>&1 | head -1); echo "=$foo="'
+expected-stdout:
+	=GNU bash, version 2.05b.0(1)-release (i386-ecce-mirbsd10)=
+expected-stderr-pattern:
+	/.*/
+---

exec.c

@@ -23,7 +23,7 @@
 
 #include "sh.h"
 
-__RCSID("$MirOS: src/bin/mksh/exec.c,v 1.123 2013/07/21 18:36:00 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/exec.c,v 1.124 2013/07/21 18:47:18 tg Exp $");
 
 #ifndef MKSH_DEFAULT_EXECSHELL
 #define MKSH_DEFAULT_EXECSHELL	"/bin/sh"
@@ -138,11 +138,6 @@ execute(struct op * volatile t,
 			/* Allow option parsing (bizarre, but POSIX) */
 			timex_hook(t, &up);
 		ap = (const char **)up;
-		if (Flag(FXTRACE)) {
-			shf_puts(substitute(str_val(global("PS4")), 0),
-			    shl_out);
-			Flag(FXTRACE) = 2;
-		}
 		if (ap[0])
 			tp = findcom(ap[0], FC_BI|FC_FUNC);
 	}
@@ -639,6 +634,8 @@ comexec(struct op *t, struct tbl * volatile tp, const char **ap,
 	l_assign = e->loc;
 	if (Flag(FEXPORT))
 		type_flags |= EXPORT;
+	if (Flag(FXTRACE))
+		change_xtrace(2, false);
 	for (i = 0; t->vars[i]; i++) {
 		/* do NOT lookup in the new var/fn block just created */
 		e->loc = l_expand;
@@ -652,9 +649,9 @@ comexec(struct op *t, struct tbl * volatile tp, const char **ap,
 				++ccp;
 			if (*ccp == '=')
 				++ccp;
-			shf_write(cp, ccp - cp, shl_out);
+			shf_write(cp, ccp - cp, shl_xtrace);
-			print_value_quoted(shl_out, ccp);
+			print_value_quoted(shl_xtrace, ccp);
-			shf_putc(' ', shl_out);
+			shf_putc(' ', shl_xtrace);
 		}
 		/* but assign in there as usual */
 		typeset(cp, type_flags, 0, 0, 0);
@@ -663,17 +660,16 @@ comexec(struct op *t, struct tbl * volatile tp, const char **ap,
 	}
 
 	if (Flag(FXTRACE)) {
+		change_xtrace(2, false);
 		if (ap[rv = 0]) {
  xtrace_ap_loop:
-			print_value_quoted(shl_out, ap[rv]);
+			print_value_quoted(shl_xtrace, ap[rv]);
 			if (ap[++rv]) {
-				shf_putc(' ', shl_out);
+				shf_putc(' ', shl_xtrace);
 				goto xtrace_ap_loop;
 			}
 		}
-		shf_putc('\n', shl_out);
+		change_xtrace(1, false);
-		Flag(FXTRACE) = 1;
-		shf_flush(shl_out);
 	}
 
 	if ((cp = *ap) == NULL) {
@@ -756,9 +752,9 @@ comexec(struct op *t, struct tbl * volatile tp, const char **ap,
 			getopts_reset(1);
 		}
 
-		old_xflag = Flag(FXTRACE);
+		old_xflag = Flag(FXTRACE) ? 1 : 0;
-		Flag(FXTRACE) |= tp->flag & TRACE ? 1 : 0;
+		change_xtrace((Flag(FXTRACEREC) ? old_xflag : 0) |
-
+		    ((tp->flag & TRACE) ? 1 : 0), false);
 		old_inuse = tp->flag & FINUSE;
 		tp->flag |= FINUSE;
 
@@ -767,9 +763,11 @@ comexec(struct op *t, struct tbl * volatile tp, const char **ap,
 			execute(tp->val.t, flags & XERROK, NULL);
 			i = LRETURN;
 		}
+
 		kshname = old_kshname;
-		Flag(FXTRACE) = old_xflag;
+		change_xtrace(old_xflag, false);
 		tp->flag = (tp->flag & ~FINUSE) | old_inuse;
+
 		/*
 		 * Were we deleted while executing? If so, free the
 		 * execution tree. TODO: Unfortunately, the table entry
@@ -1310,8 +1308,11 @@ iosetup(struct ioword *iop, struct tbl *tp)
 	iotmp.name = (iotype == IOHERE) ? NULL : cp;
 	iotmp.flag |= IONAMEXP;
 
-	if (Flag(FXTRACE) == 2)
+	if (Flag(FXTRACE)) {
-		fptreef(shl_out, 0, "%R", &iotmp);
+		change_xtrace(2, false);
+		fptreef(shl_xtrace, 0, "%R", &iotmp);
+		change_xtrace(1, false);
+	}
 
 	switch (iotype) {
 	case IOREAD:

main.c

@@ -34,7 +34,7 @@
 #include <locale.h>
 #endif
 
-__RCSID("$MirOS: src/bin/mksh/main.c,v 1.267 2013/07/21 18:36:01 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/main.c,v 1.268 2013/07/21 18:47:19 tg Exp $");
 
 extern char **environ;
 
@@ -343,6 +343,11 @@ main_init(int argc, const char *argv[], Source **sp, struct block **lp)
 	 */
 	Flag(FBRACEEXPAND) = 1;
 
+	/*
+	 * Turn on "set -x" inheritance by default.
+	 */
+	Flag(FXTRACEREC) = 1;
+
 #ifndef MKSH_NO_CMDLINE_EDITING
 	/*
 	 * Set edit mode to emacs by default, may be overridden
@@ -1388,7 +1393,7 @@ initio(void)
 	/* force buffer allocation */
 	shf_fdopen(1, SHF_WR, shl_stdout);
 	shf_fdopen(2, SHF_WR, shl_out);
-	shf_fdopen(2, SHF_WR, shl_spare);
+	shf_fdopen(2, SHF_WR, shl_xtrace);
 #ifdef DF
 	if ((lfp = getenv("SDMKSH_PATH")) == NULL) {
 		if ((lfp = getenv("HOME")) == NULL || *lfp != '/')

misc.c

@@ -30,7 +30,7 @@
 #include <grp.h>
 #endif
 
-__RCSID("$MirOS: src/bin/mksh/misc.c,v 1.212 2013/06/03 22:28:05 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/misc.c,v 1.213 2013/07/21 18:47:20 tg Exp $");
 
 #define KSH_CHVT_FLAG
 #ifdef MKSH_SMALL
@@ -229,8 +229,12 @@ void
 change_flag(enum sh_flag f, int what, bool newset)
 {
 	unsigned char oldval;
-	unsigned char newval;
+	unsigned char newval = (newset ? 1 : 0);
 
+	if (f == FXTRACE) {
+		change_xtrace(newval, true);
+		return;
+	}
 	oldval = Flag(f);
 	Flag(f) = newval = (newset ? 1 : 0);
 #ifndef MKSH_UNEMPLOYED
@@ -286,6 +290,37 @@ change_flag(enum sh_flag f, int what, bool newset)
 	}
 }
 
+void
+change_xtrace(unsigned char newval, bool dosnapshot)
+{
+	if (!dosnapshot && newval == Flag(FXTRACE))
+		return;
+
+	if (Flag(FXTRACE) == 2) {
+		shf_putc('\n', shl_xtrace);
+		Flag(FXTRACE) = 1;
+		shf_flush(shl_xtrace);
+	}
+
+	if (!dosnapshot && Flag(FXTRACE) == 1)
+		switch (newval) {
+		case 1:
+			return;
+		case 2:
+			goto changed_xtrace;
+		}
+
+	shf_flush(shl_xtrace);
+	if (shl_xtrace->fd != 2)
+		close(shl_xtrace->fd);
+	if (!newval || (shl_xtrace->fd = savefd(2)) == -1)
+		shl_xtrace->fd = 2;
+
+ changed_xtrace:
+	if ((Flag(FXTRACE) = newval) == 2)
+		shf_puts(substitute(str_val(global("PS4")), 0), shl_xtrace);
+}
+
 /*
  * Parse command line and set command arguments. Returns the index of
  * non-option arguments, -1 if there is an error.
@@ -444,8 +479,10 @@ parse_args(const char **argv,
 	    (argv[go.optind][0] == '-' || argv[go.optind][0] == '+') &&
 	    argv[go.optind][1] == '\0') {
 		/* lone - clears -v and -x flags */
-		if (argv[go.optind][0] == '-')
+		if (argv[go.optind][0] == '-') {
-			Flag(FVERBOSE) = Flag(FXTRACE) = 0;
+			Flag(FVERBOSE) = 0;
+			change_xtrace(0, false);
+		}
 		/* set skips lone - or + option */
 		go.optind++;
 	}

mksh.1

@@ -1,4 +1,4 @@
-.\" $MirOS: src/bin/mksh/mksh.1,v 1.317 2013/07/21 18:36:02 tg Exp $
+.\" $MirOS: src/bin/mksh/mksh.1,v 1.318 2013/07/21 18:47:21 tg Exp $
 .\" $OpenBSD: ksh.1,v 1.147 2013/06/13 19:43:09 millert Exp $
 .\"-
 .\" Copyright © 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
@@ -4165,6 +4165,11 @@ must be used.
 To avoid infinite loops, the shell will exit if
 .Dv EOF
 is read 13 times in a row.
+.It Fl o Ic inherit\-xtrace
+Do not reset
+.Fl o Ic xtrace
+upon entering functions.
+This is enabled by default.
 .It Fl o Ic nohup
 Do not kill running jobs with a
 .Dv SIGHUP

sh.h

@@ -164,9 +164,9 @@
 #endif
 
 #ifdef EXTERN
-__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.659 2013/06/03 22:28:33 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.660 2013/07/21 18:47:22 tg Exp $");
 #endif
-#define MKSH_VERSION "R46 2013/06/03"
+#define MKSH_VERSION "R47 2013/07/21"
 
 /* arithmetic types: C implementation */
 #if !HAVE_CAN_INTTYPES
@@ -520,7 +520,7 @@ char *ucstrstr(char *, const char *);
 #define mkssert(e)	do { } while (/* CONSTCOND */ 0)
 #endif
 
-#if (!defined(MKSH_BUILDMAKEFILE4BSD) && !defined(MKSH_BUILDSH)) || (MKSH_BUILD_R != 469)
+#if (!defined(MKSH_BUILDMAKEFILE4BSD) && !defined(MKSH_BUILDSH)) || (MKSH_BUILD_R != 471)
 #error Must run Build.sh to compile this.
 extern void thiswillneverbedefinedIhope(void);
 int
@@ -838,7 +838,7 @@ struct temp {
  * stdio and our IO routines
  */
 
-#define shl_spare	(&shf_iob[0])	/* for c_read()/c_print() */
+#define shl_xtrace	(&shf_iob[0])	/* for set -x */
 #define shl_stdout	(&shf_iob[1])
 #define shl_out		(&shf_iob[2])
 #ifdef DF
@@ -1906,6 +1906,7 @@ void initctypes(void);
 size_t option(const char *);
 char *getoptions(void);
 void change_flag(enum sh_flag, int, bool);
+void change_xtrace(unsigned char, bool);
 int parse_args(const char **, int, bool *);
 int getn(const char *, int *);
 int gmatchx(const char *, const char *, bool);

sh_flags.h

@@ -1,5 +1,5 @@
 #if defined(SHFLAGS_DEFNS)
-__RCSID("$MirOS: src/bin/mksh/sh_flags.h,v 1.14 2013/05/02 20:28:15 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/sh_flags.h,v 1.15 2013/07/21 18:47:24 tg Exp $");
 #define FN(sname,cname,ochar,flags)	/* nothing */
 #elif defined(SHFLAGS_ENUMS)
 #define FN(sname,cname,ochar,flags)	cname,
@@ -45,6 +45,9 @@ FN("gmacs", FGMACS, 0, OF_ANY)
 /* ./.	reading EOF does not exit */
 FN("ignoreeof", FIGNOREEOF, 0, OF_ANY)
 
+/* ./.	inherit -x flag */
+FN("inherit-xtrace", FXTRACEREC, 0, OF_ANY)
+
 /* -i	interactive shell */
 FN("interactive", FTALKING, 'i', OF_CMDLINE)