PSARC/2008/094 ksh93 Update 1

PSARC/2008/344 ksh93 Integration Update 1 Amendments 1
PSARC/2008/589 Remove /usr/bin/printf from PSARC case 2008 094
6619428 *ksh93* RFE: Update ksh93 in Solaris to ast-ksh.2008-11-04
6788659 RFE: Update libpp in Solaris to ast-open.2008-07-25
6561901 RFE: Add "shcomp" (shell script compiler) + kernel module to exec binary sh code
6599668 RFE: Move consumers of alias.sh over to ksh93
6595183 *ksh93* RFE: Update ksh93-integration demo code
6775901 *ksh93* no C message catalogs are generated for ksh93
6451262 *sleep* RFE: /usr/bin/sleep should support floating-point values
6687139 *ksh93* command substitution, exec, and stdout redirection cause allocation loop
6703761 *ksh93* crashes in script containing uncommon output redirections
6715496 *ksh93* SEGVs on array reinitialization
6713682 *ksh93* Creating a compound variable in a subshell "bleeds through" to the calling subshell
6672350 *ksh93* causes parent shell to die when child shell is suspended
6745015 *ksh93* VARIABLE=`command substitution` assignment is not reliable on OpenSolaris
6710205 *ksh93* problem with command substitution (within back quotes) containing \$'
6737600 *ksh93* exits debugger when user presses ctrl-c
6748645 *ksh93* fc -l -e - is mis-parsed, outputs wrong error message "-e - requires single argument"
6754020 *ksh93* does weird '[' expansion
6753538 *ksh93* umask modification leaks out of a ksh93 subshell
6766246 *ksh93* bug in pattern matching
6763594 *ksh93* executes command after "command" builtin twice on failure
6762665 *ksh93* Difficult-to-reproduce SIGSEGV in ksh93

1 files changed, 267 insertions, 0 deletions

diff --git a/usr/src/lib/libshell/common/scripts/filemutexdemo1.sh b/usr/src/lib/libshell/common/scripts/filemutexdemo1.sh
new file mode 100644
index 0000000000..1de54a92fc
--- /dev/null
+++ b/usr/src/lib/libshell/common/scripts/filemutexdemo1.sh
@@ -0,0 +1,267 @@
+#!/usr/bin/ksh93
+
+#
+# CDDL HEADER START
+#
+# The contents of this file are subject to the terms of the
+# Common Development and Distribution License (the "License").
+# You may not use this file except in compliance with the License.
+#
+# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+# or http://www.opensolaris.org/os/licensing.
+# See the License for the specific language governing permissions
+# and limitations under the License.
+#
+# When distributing Covered Code, include this CDDL HEADER in each
+# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+# If applicable, add the following below this CDDL HEADER, with the
+# fields enclosed by brackets "[]" replaced with your own identifying
+# information: Portions Copyright [yyyy] [name of copyright owner]
+#
+# CDDL HEADER END
+#
+
+#
+# Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
+# Use is subject to license terms.
+#
+
+#
+# filemutexdemo1 - a simple locking demo which supports read/write
+# locks and critical sections (like JAVA's "syncronized" keyword)
+#
+
+# Solaris needs /usr/xpg6/bin:/usr/xpg4/bin because the tools in /usr/bin are not POSIX-conformant
+export PATH=/usr/xpg6/bin:/usr/xpg4/bin:/bin:/usr/bin
+
+# Make sure all math stuff runs in the "C" locale to avoid problems
+# with alternative # radix point representations (e.g. ',' instead of
+# '.' in de_DE.*-locales). This needs to be set _before_ any
+# floating-point constants are defined in this script).
+if [[ "${LC_ALL}" != "" ]] ; then
+    export \
+        LC_MONETARY="${LC_ALL}" \
+        LC_MESSAGES="${LC_ALL}" \
+        LC_COLLATE="${LC_ALL}" \
+        LC_CTYPE="${LC_ALL}"
+        unset LC_ALL
+fi
+export LC_NUMERIC=C
+
+# Definition for a mutex which uses the filesystem for locking
+typeset -T filemutex_t=(
+	typeset name
+	
+	typeset lock_dirname
+	
+	typeset locked_exclusive="false"
+	typeset locked_shared="false"
+	
+	# keep track of subshell level. The problem is that we do not know a
+	# way to figure out whether someone calls "unlock" in a subshell and then
+	# leaves the subshell and calls "unlock" again
+	integer subshell=-1
+	
+	typeset lock_dirname
+	
+	# create a filemutex instance (including lock directory)
+	function create
+	{
+		# make sure we return an error if the init didn't work
+		set -o errexit
+
+		[[ "$1" == "" ]] && return 1
+		
+		_.name="$1"
+		_.lock_dirname="/tmp/filemutex_t_${_.name}.lock"
+		
+		mkdir "${_.lock_dirname}"
+		
+		# last entry, used to mark the mutex as initalised+valid
+		(( _.subshell=.sh.subshell ))
+		return 0
+	}
+
+	# use a filemutex instance (same as "create" but without creating 
+	# the lock directory)
+	function create_child
+	{
+		# make sure we return an error if the init didn't work
+		set -o errexit
+
+		[[ "$1" == "" ]] && return 1
+		
+		_.name="$1"
+		_.lock_dirname="/tmp/filemutex_t_${_.name}.lock"
+		
+		# last entry, used to mark the mutex as initalised+valid
+		(( _.subshell=.sh.subshell ))
+		return 0
+	}
+	
+	function check_subshell
+	{
+		(( _.subshell == .sh.subshell )) && return 0
+		print -u2 -f "filemutex_t.%s(%s): Wrong subshell level\n" "$1" "${_.name}"
+		return 1
+	}
+
+	function try_lock_shared
+	{
+		_.check_subshell "try_lock_shared" || return 1
+		
+		mkdir "${_.lock_dirname}/shared_${PPID}_$$" 2>/dev/null || return 1
+		_.locked_shared="true"
+		return 0
+	}
+	
+	function lock_shared
+	{
+		float interval=0.2
+
+		_.check_subshell "lock_shared" || return 1
+		
+		while ! _.try_lock_shared ; do sleep ${interval} ; (( interval+=interval/10. )) ; done
+		return 0
+	}
+
+	function try_lock_exclusive
+	{
+		_.check_subshell "try_lock_exclusive" || return 1
+		
+		rmdir "${_.lock_dirname}" 2>/dev/null || return 1
+		_.locked_exclusive="true"
+		return 0
+	}
+			
+	function lock_exclusive
+	{
+		float interval=0.2
+		
+		_.check_subshell "lock_exclusive" || return 1
+		
+		while ! _.try_lock_exclusive ; do sleep ${interval} ; (( interval+=interval/10. )) ; done
+		return 0
+	}
+	
+	# critical section support (like java's "synchronized" keyword)
+	function synchronized
+	{
+		integer retcode
+
+		_.check_subshell "synchronized" || return 1
+		
+		_.lock_exclusive
+		
+		"$@"
+		(( retcode=$? ))
+
+		_.unlock
+		
+		return ${retcode}
+	}
+
+	# critical section support with shared lock
+	function synchronized_shared
+	{
+		integer retcode
+
+		_.check_subshell "synchronized_shared" || return 1
+		
+		_.lock_shared
+		
+		"$@"
+		(( retcode=$? ))
+
+		_.unlock
+		
+		return ${retcode}
+	}
+		
+	function unlock
+	{
+		# return an error if rmdir/mkdir/check_subshell fail...
+		set -o errexit
+		
+		_.check_subshell "unlock"
+
+		if ${_.locked_shared} ; then
+			rmdir "${_.lock_dirname}/shared_${PPID}_$$"
+			_.locked_shared="false"
+			return 0
+		elif ${_.locked_exclusive} ; then
+			mkdir "${_.lock_dirname}"
+			_.locked_exclusive="false"
+			return 0
+		fi
+
+		print -u2 -f "filemutex_t.unlock(%s): mutex '%s' not locked." "$1" "${_.name}"
+		return 1
+	}
+	
+	# destroy mutex if noone is using it anymore (not the same as "unset" !!))
+	function destroy
+	{
+		_.check_subshell "destroy" || return 1
+
+		(${_.locked_exclusive} || ${_.locked_shared}) && _.unlock
+		rmdir "${_.lock_dirname}"
+		return 0
+	}
+)
+
+# main
+builtin mkdir
+builtin rmdir
+
+print "## Start."
+
+typeset -r mymutexname="hello_world"
+
+filemutex_t fs
+
+fs.create "${mymutexname}" || print -u2 "Mutex init failed."
+
+print "# Starting child which keeps an exclusive lock for 10 seconds..."
+(
+	filemutex_t child_fs
+	
+	child_fs.create_child "${mymutexname}"
+
+	child_fs.lock_exclusive
+	sleep 10
+	child_fs.unlock
+) &
+
+sleep 1
+
+printf "%T: # Waiting to obtain a shared lock...\n"
+fs.lock_shared
+printf "%T: # Obtained shared lock\n"
+
+printf "fs.locked_exclusive=%s, fs.locked_shared=%s\n" "${fs.locked_exclusive}" "${fs.locked_shared}"
+
+ls -lad /tmp/filemutex*/*
+
+printf "%T: # Executing child which runs printf '|%%s|\\\n' 'hello' 'world' inside a synchronized section\n"
+(
+	filemutex_t child_fs
+	
+	child_fs.create_child "${mymutexname}"
+
+	child_fs.synchronized printf '|%s|\n' 'hello' 'world'
+) &
+
+printf "%T: # Sleeping 5 secs while holding the shared lock...\n"
+sleep 5.
+
+printf "%T: # Releasing shared lock...\n"
+fs.unlock
+
+sleep 5.
+print "# Destroying lock..."
+fs.destroy
+
+print "## Done."
+
+exit 0