Backport upstream patch for rhbz#1258142

- makes dejagnu not to kill wrong process due to PID-reuse races

dejagnu-1.5.3-wrong-kill.patch

@@ -0,0 +1,117 @@
+Upstream patch: http://git.savannah.gnu.org/gitweb/?p=dejagnu.git;a=commitdiff;h=e7d7a3e0b0cda9194c192e979f4ecc8dcfb010b3
+
+rhbz#1258142
+
+diff --git a/lib/remote.exp b/lib/remote.exp
+--- a/lib/remote.exp
++++ b/lib/remote.exp
+@@ -56,6 +56,61 @@ proc remote_raw_open { args } {
+     return [eval call_remote raw open $args]
+ }
+ 
++# Close a spawn ID, and wait for the process to die.  If PID is not
++# -1, then if the process doesn't exit gracefully promptly, we kill
++# it.
++#
++proc close_wait_program { program_id pid {wres_varname ""} } {
++    if {$wres_varname != "" } {
++       upvar 1 $wres_varname wres
++    }
++
++    set exec_pid -1
++
++    if { $pid > 0 } {
++       # Tcl has no kill primitive, so we have to execute an external
++       # command in order to kill the process.
++       verbose "doing kill, pid is $pid"
++       # Prepend "-" to generate the "process group ID" needed by
++       # kill.
++       set pgid "-$pid"
++       # Send SIGINT to give the program a better chance to interrupt
++       # whatever it might be doing and react to stdin closing.
++       # E.g., in case of GDB, this should get it back to the prompt.
++       exec sh -c "exec > /dev/null 2>&1 && (kill -2 $pgid || kill -2 $pid)"
++
++       # If the program doesn't exit gracefully when stdin closes,
++       # we'll need to kill it.  But only do this after 'wait'ing a
++       # bit, to avoid killing the wrong process in case of a
++       # PID-reuse race.  The extra sleep at the end is there to give
++       # time to kill $exec_pid without having _that_ be subject to a
++       # PID reuse race.
++       set secs 5
++       set sh_cmd "exec > /dev/null 2>&1"
++       append sh_cmd " && sleep $secs && (kill -15 $pgid || kill -15 $pid)"
++       append sh_cmd " && sleep $secs && (kill -9 $pgid || kill -9 $pid)"
++       append sh_cmd " && sleep $secs"
++       set exec_pid [exec sh -c "$sh_cmd" &]
++    }
++    verbose "pid is $pid"
++
++    # This closes the program's stdin.  This should cause well behaved
++    # interactive programs to exit.  This will hang if the kill
++    # doesn't work.  Nothin' to do, and it's not OK.
++    catch "close -i $program_id"
++
++    # Reap it.
++    set res [catch "wait -i $program_id" wres]
++    if {$exec_pid != -1} {
++       # We reaped the process, so cancel the pending force-kills, as
++       # otherwise if the PID is reused for some other unrelated
++       # process, we'd kill the wrong process.
++       exec sh -c "exec > /dev/null 2>&1 && kill -9 $exec_pid"
++    }
++
++    return $res
++}
++
+ # Run the specified COMMANDLINE on the local machine, redirecting input
+ # to file INP (if non-empty), redirecting output to file OUTP (if non-empty),
+ # and waiting TIMEOUT seconds for the command to complete before killing
+@@ -174,18 +229,10 @@ proc local_exec { commandline inp outp timeout } {
+ 
+     # Uuuuuuugh. Now I'm getting really sick.
+     # If we didn't get an EOF, we have to kill the poor defenseless program.
+-    # However, Tcl has no kill primitive, so we have to execute an external
+-    # command in order to execute the execution. (English. Gotta love it.)
+-    if { ! $got_eof } {
+-	verbose "killing $pid $pgid"
+-	# This is very, very nasty. SH, instead of EXPECT, is used to
+-	# run this in the background since, on older CYGWINs, a
+-	# strange file I/O error occures.
+-	exec sh -c "exec > /dev/null 2>&1 && (kill -2 $pgid || kill -2 $pid) && sleep 5 && (kill -15 $pgid || kill $pid) && sleep 5 && (kill -9 $pgid || kill -9 $pid) &"
+-    }
+-    # This will hang if the kill doesn't work. Nothin' to do, and it's not ok.
+-    catch "close -i $spawn_id"
+-    set r2 [catch "wait -i $spawn_id" wres]
++    if { $got_eof } {
++       set pid -1
++    }
++    set r2 [close_wait_program $spawn_id $pid wres]
+     if { $id > 0 } {
+ 	set r2 [catch "close $id" res]
+     } else {
+@@ -312,20 +359,13 @@ proc standard_close { host } {
+ 		}
+ 	    }
+ 	}
+-	if { $pid > 0 } {
+-	    verbose "doing kill, pid is $pid"
+-	    # This is very, very nasty. SH, instead of EXPECT, is used
+-	    # to run this in the background since, on older CYGWINs, a
+-	    # strange file I/O error occures.
+-	    set pgid "-[join $pid { -}]"
+-	    exec sh -c "exec > /dev/null 2>&1 && (kill -2 $pgid || kill -2 $pid) && sleep 5 && (kill $pgid || kill $pid) && sleep 5 && (kill -9 $pgid || kill -9 $pid) &"
+-	}
+-	verbose "pid is $pid"
+-	catch "close -i $shell_id"
++
++       close_wait_program $shell_id $pid
++
+ 	if {[info exists oid]} {
+ 	    catch "close $oid"
+ 	}
+-	catch "wait -i $shell_id"
++
+ 	unset board_info(${host},fileid)
+ 	verbose "Shell closed."
+     }

dejagnu.spec

@@ -1,7 +1,7 @@
 Summary: A front end for testing other programs
 Name: dejagnu
 Version: 1.5.3
-Release: 2%{?dist}
+Release: 3%{?dist}
 Epoch: 1
 License: GPLv3+
 Source: ftp://ftp.gnu.org/gnu/dejagnu/dejagnu-%{version}.tar.gz
@@ -10,6 +10,7 @@ URL: http://www.gnu.org/software/dejagnu/
 Requires: expect
 BuildArch: noarch
 BuildRequires: expect screen texinfo
+Patch0:     dejagnu-1.5.3-wrong-kill.patch
 
 %description
 DejaGnu is an Expect/Tcl based framework for testing other programs.
@@ -21,6 +22,7 @@ into software development).
 
 %prep
 %setup -q
+%patch0 -p1 -b .wrong-kill
 
 %build
 %configure -v
@@ -68,10 +70,15 @@ rm -rf $RPM_BUILD_ROOT
 %{_infodir}/dejagnu*
 
 %changelog
+* Mon Aug 31 2015 Matej Muzila <mmuzila@redhat.com> 1:1.5.3-3
+- Backport upstream patch making dejagnu not to kill wrong process due to
+  PID-reuse races
+- Resolves rhbz#1258142
+
 * Wed Jun 17 2015 Fedora Release Engineering <rel-eng@lists.fedoraproject.org> - 1:1.5.3-2
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_23_Mass_Rebuild
 
-* Tue Mar 31 2015 Matej Muzila <mmuzila@redhat.com> 1:1.5.2-1
+* Tue Mar 31 2015 Matej Muzila <mmuzila@redhat.com> 1:1.5.3-1
 - Update to 1.5.3
 
 * Thu Feb 12 2015 Matej Muzila <mmuzila@redhat.com> 1:1.5.2-1