[PATCH 1/2] testsuite: refactor spawn and wait for attach (was: Re: Regression: GDB stopped on run with attached process)

Pedro Alves
2014-09-08T16:19:28Z

On 09/07/2014 08:28 PM, Jan Kratochvil wrote:
>> > --- a/gdb/testsuite/gdb.base/attach.exp
>> > +++ b/gdb/testsuite/gdb.base/attach.exp
>> > @@ -58,6 +58,37 @@ if [get_compiler_info] {
>> > return -1
>> > }
>> >
>> > +# Start the program running and then wait for a bit, to be sure that
>> > +# it can be attached to. Return the process's PID.
>> > +
>> > +proc spawn_test_prog { executable } {
>> > + set testpid [eval exec $executable &]
>> > + exec sleep 2
> Unrelated to this patch - this patch only moved the code. Also the code move
> could be a separate patch:

Indeed it could. I've done that now. See below. There were actually more
places around the testsuite that have that same code. Let me know how it looks
to you.

> I do not see why the testsuite commonly uses "exec sleep" while it also uses
> "sleep" itself which also works fine.

No idea, though I'd guess that there's really no good reason.

------ 8< -------
[PATCH 1/2] testsuite: refactor spawn and wait for attach

Several places in the testsuite have a copy of a snippet of code that
spawns a test program, waits a bit, and then does some PID munging for
Cygwin. This is in order to have GDB attach to the spawned program.

This refactors all that to a common procedure.

(multi-attach.exp wants to spawn multiple processes, so this makes the
new procedure's interface work with lists.)

Tested on x86_64 Fedora 20.

gdb/testsuite/ChangeLog:
2014-09-08 Pedro Alves <palves@redhat.com>

* lib/gdb.exp (spawn_wait_for_attach): New procedure.
* gdb.base/attach.exp (do_attach_tests, do_call_attach_tests)
(do_command_attach_tests): Use spawn_wait_for_attach.
* gdb.base/solib-overlap.exp: Likewise.
* gdb.multi/multi-attach.exp: Likewise.
* gdb.python/py-prompt.exp: Likewise.
* gdb.python/py-sync-interp.exp: Likewise.
* gdb.server/ext-attach.exp: Likewise.
---
gdb/testsuite/gdb.base/attach.exp | 41 +++--------------------------
gdb/testsuite/gdb.base/solib-overlap.exp | 11 +-------
gdb/testsuite/gdb.multi/multi-attach.exp | 13 +++------
gdb/testsuite/gdb.python/py-prompt.exp | 10 +------
gdb/testsuite/gdb.python/py-sync-interp.exp | 10 +------
gdb/testsuite/gdb.server/ext-attach.exp | 10 +------
gdb/testsuite/lib/gdb.exp | 25 ++++++++++++++++++
7 files changed, 37 insertions(+), 83 deletions(-)

diff --git a/gdb/testsuite/gdb.base/attach.exp b/gdb/testsuite/gdb.base/attach.exp
index 9714c29..a20c51a 100644
--- a/gdb/testsuite/gdb.base/attach.exp
+++ b/gdb/testsuite/gdb.base/attach.exp
@@ -70,13 +70,7 @@ proc do_attach_tests {} {
# Start the program running and then wait for a bit, to be sure
# that it can be attached to.

- set testpid [eval exec $binfile &]
- exec sleep 2
- if { [istarget "*-*-cygwin*"] } {
- # testpid is the Cygwin PID, GDB uses the Windows PID, which might be
- # different due to the way fork/exec works.
- set testpid [ exec ps -e | gawk "{ if (\$1 == $testpid) print \$4; }" ]
- }
+ set testpid [spawn_wait_for_attach $binfile]

# Verify that we cannot attach to nonsense.

@@ -279,16 +273,7 @@ proc do_attach_tests {} {

remote_exec build "kill -9 ${testpid}"

- # Start the program running and then wait for a bit, to be sure
- # that it can be attached to.
-
- set testpid [eval exec $binfile &]
- exec sleep 2
- if { [istarget "*-*-cygwin*"] } {
- # testpid is the Cygwin PID, GDB uses the Windows PID, which might be
- # different due to the way fork/exec works.
- set testpid [ exec ps -e | gawk "{ if (\$1 == $testpid) print \$4; }" ]
- }
+ set testpid [spawn_wait_for_attach $binfile]

# Verify that we can attach to the process, and find its a.out
# when we're cd'd to some directory that doesn't contain the
@@ -335,16 +320,7 @@ proc do_call_attach_tests {} {
global gdb_prompt
global binfile2

- # Start the program running and then wait for a bit, to be sure
- # that it can be attached to.
-
- set testpid [eval exec $binfile2 &]
- exec sleep 2
- if { [istarget "*-*-cygwin*"] } {
- # testpid is the Cygwin PID, GDB uses the Windows PID, which might be
- # different due to the way fork/exec works.
- set testpid [ exec ps -e | gawk "{ if (\$1 == $testpid) print \$4; }" ]
- }
+ set testpid [spawn_wait_for_attach $binfile2]

# Attach

@@ -397,16 +373,7 @@ proc do_command_attach_tests {} {
return 0
}

- # Start the program running and then wait for a bit, to be sure
- # that it can be attached to.
-
- set testpid [eval exec $binfile &]
- exec sleep 2
- if { [istarget "*-*-cygwin*"] } {
- # testpid is the Cygwin PID, GDB uses the Windows PID, which might be
- # different due to the way fork/exec works.
- set testpid [ exec ps -e | gawk "{ if (\$1 == $testpid) print \$4; }" ]
- }
+ set testpid [spawn_wait_for_attach $binfile]

gdb_exit
if $verbose>1 then {
diff --git a/gdb/testsuite/gdb.base/solib-overlap.exp b/gdb/testsuite/gdb.base/solib-overlap.exp
index 68731be..7486b07 100644
--- a/gdb/testsuite/gdb.base/solib-overlap.exp
+++ b/gdb/testsuite/gdb.base/solib-overlap.exp
@@ -82,16 +82,7 @@ foreach prelink_lib1 {0x40000000 0x50000000} { with_test_prefix "$prelink_lib1"
return -1
}

- # Start the program running and then wait for a bit, to be sure
- # that it can be attached to.
-
- set testpid [eval exec $binfile &]
- sleep 2
- if { [istarget "*-*-cygwin*"] } {
- # testpid is the Cygwin PID, GDB uses the Windows PID, which might be
- # different due to the way fork/exec works.
- set testpid [ exec ps -e | gawk "{ if (\$1 == $testpid) print \$4; }" ]
- }
+ set testpid [spawn_wait_for_attach $binfile]

remote_exec build "mv -f ${binfile_lib1} ${binfile_lib1}-running"
remote_exec build "mv -f ${binfile_lib2} ${binfile_lib2}-running"
diff --git a/gdb/testsuite/gdb.multi/multi-attach.exp b/gdb/testsuite/gdb.multi/multi-attach.exp
index e933520..eaff2c9 100644
--- a/gdb/testsuite/gdb.multi/multi-attach.exp
+++ b/gdb/testsuite/gdb.multi/multi-attach.exp
@@ -30,15 +30,10 @@ if {[prepare_for_testing "failed to prepare" $testfile $srcfile {debug additiona

# Start the programs running and then wait for a bit, to be sure that
# they can be attached to.
-set testpid1 [eval exec $binfile &]
-set testpid2 [eval exec $binfile &]
-exec sleep 2
-if { [istarget "*-*-cygwin*"] } {
- # testpid{1,2} are the Cygwin PID, GDB uses the Windows PID, which might be
- # different due to the way fork/exec works.
- set testpid1 [ exec ps -e | gawk "{ if (\$1 == $testpid1) print \$4; }" ]
- set testpid2 [ exec ps -e | gawk "{ if (\$1 == $testpid2) print \$4; }" ]
-}
+
+set pid_list [spawn_wait_for_attach [list $binfile $binfile]]
+set testpid1 [lindex $pid_list 0]
+set testpid2 [lindex $pid_list 1]

gdb_test "attach $testpid1" \
"Attaching to program: .*, process $testpid1.*(in|at).*" \
diff --git a/gdb/testsuite/gdb.python/py-prompt.exp b/gdb/testsuite/gdb.python/py-prompt.exp
index ebe4cb6..1c53c03 100644
--- a/gdb/testsuite/gdb.python/py-prompt.exp
+++ b/gdb/testsuite/gdb.python/py-prompt.exp
@@ -80,15 +80,7 @@ gdb_test "python print (\"'\" + str(p\[0\]) + \"'\")" "'$gdb_prompt_fail '" \
"prompt_hook argument is default prompt. 2"
gdb_exit

-# Start the program running and then wait for a bit, to be sure
-# that it can be attached to.
-set testpid [eval exec $binfile &]
-exec sleep 2
-if { [istarget "*-*-cygwin*"] } {
- # testpid is the Cygwin PID, GDB uses the Windows PID, which might be
- # different due to the way fork/exec works.
- set testpid [ exec ps -e | gawk "{ if (\$1 == $testpid) print \$4; }" ]
-}
+set testpid [spawn_wait_for_attach $binfile]

set GDBFLAGS [concat $tmp_gdbflags " -ex \"set pagination off\""]
set GDBFLAGS [concat $GDBFLAGS " -ex \"set editing on\""]
diff --git a/gdb/testsuite/gdb.python/py-sync-interp.exp b/gdb/testsuite/gdb.python/py-sync-interp.exp
index b9b86bc..d62f966 100644
--- a/gdb/testsuite/gdb.python/py-sync-interp.exp
+++ b/gdb/testsuite/gdb.python/py-sync-interp.exp
@@ -41,15 +41,7 @@ if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile}] } {
return -1
}

-# Start the program running and then wait for a bit, to be sure
-# that it can be attached to.
-set testpid [eval exec $binfile &]
-exec sleep 2
-if { [istarget "*-*-cygwin*"] } {
- # testpid is the Cygwin PID, GDB uses the Windows PID, which might be
- # different due to the way fork/exec works.
- set testpid [ exec ps -e | gawk "{ if (\$1 == $testpid) print \$4; }" ]
-}
+set testpid [spawn_wait_for_attach $binfile]

# Test command 'where' is executed when command 'attach' is done, otherwise
# function 'sleep' may not show up in backtrace.
diff --git a/gdb/testsuite/gdb.server/ext-attach.exp b/gdb/testsuite/gdb.server/ext-attach.exp
index 5f7bac4..9baeeb7 100644
--- a/gdb/testsuite/gdb.server/ext-attach.exp
+++ b/gdb/testsuite/gdb.server/ext-attach.exp
@@ -44,15 +44,7 @@ gdbserver_start_extended

gdb_test_no_output "set remote exec-file $target_exec" "set remote exec-file"

-# Start the program running and then wait for a bit, to be sure
-# that it can be attached to.
-set testpid [eval exec $binfile &]
-exec sleep 2
-if { [istarget "*-*-cygwin*"] } {
- # testpid is the Cygwin PID, GDB uses the Windows PID, which might be
- # different due to the way fork/exec works.
- set testpid [ exec ps -e | gawk "{ if (\$1 == $testpid) print \$4; }" ]
-}
+set testpid [spawn_wait_for_attach $binfile]

gdb_test "attach $testpid" \
"Attaching to program: .*, process $testpid.*(in|at).*" \
diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
index 1019ecd..ecf942e 100644
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -3347,6 +3347,31 @@ proc gdb_exit { } {
catch default_gdb_exit
}

+# Start a set of programs running and then wait for a bit, to be sure
+# that they can be attached to. Return a list of the processes' PIDs.
+
+proc spawn_wait_for_attach { executable_list } {
+ set pid_list {}
+
+ foreach {executable} $executable_list {
+ lappend pid_list [eval exec $executable &]
+ }
+
+ sleep 2
+
+ if { [istarget "*-*-cygwin*"] } {
+ for {set i 0} {$i < [llength $pid_list]} {incr i} {
+ # testpid is the Cygwin PID, GDB uses the Windows PID,
+ # which might be different due to the way fork/exec works.
+ set testpid [lindex $pid_list $i]
+ set testpid [ exec ps -e | gawk "{ if (\$1 == $testpid) print \$4; }" ]
+ lreplace $i $i $testpid
+ }
+ }
+
+ return $pid_list
+}
+
#
# gdb_load_cmd -- load a file into the debugger.
# ARGS - additional args to load command.
--
1.9.3