Re: [PATCH][gdb/testsuite] Rewrite catch-follow-exec.exp

[Tom de Vries <tdevries@suse.de>]

[-- Attachment #1: Type: text/plain, Size: 2573 bytes --]

On 10/24/18 1:37 AM, Simon Marchi wrote:
> On 2018-10-23 6:38 p.m., Tom de Vries wrote:
>> On 10/23/18 11:05 PM, Tom de Vries wrote:
>>> On 10/23/18 11:04 PM, Simon Marchi wrote:
>>>> On 2018-10-15 3:54 p.m., Tom de Vries wrote:
>>>>>> Just wondering.  Would it make life easier if we fixed PR 23368, which
>>>>>> is the reason we have to do the test in an unnatural way?
>>>>>
>>>>> Yes.
>>>>
>>>> Hi Tom,
>>>>
>>>> PR 23368 should be fixed now.  Do you plan on updating catch-follow-exec.exp
>>>> to be written in a more standard way?
>>>
>>> Sure, will do.
>>
>> How does this look?
> 
> Hi Tom,
> 
> Thanks for looking into this so quickly.

And thanks for the quick review.

>  I have some superficial suggestions that
> can help shorten the test a bit and make it more readable (some of them can be personal
> preference though...).
> 
> When the test name is omitted, it defaults to the command.  So instead of
> 
>     gdb_test "catch exec" \
> 	{Catchpoint [0-9][0-9]* \(exec\)} \
> 	"catch exec"
> 
> You can write
> 
>     gdb_test "catch exec" {Catchpoint [0-9][0-9]* \(exec\)}
> 
> and the test name will be "catch exec".

Done.

>  Instead of [0-9][0-9]*, I am
> pretty sure you can use [0-9]+,

Done.

> or $decimal, which is provided by DejaGnu
> (/usr/share/dejagnu/runtest.exp):
> 
>   101:    set decimal "\[0-9\]+"
> 
> Except in the {} string, $decimal won't work, because it won't get
> substituted.

Indeed. I prefer the {} quoting over "" quoting if that means less
escaping, so I went with {} here.

> 
> For this:
> 
>     gdb_test "set follow-exec-mode new" \
> 	"" \
> 	"set follow-exec-mode new"
> 
> You can use
> 
>     gdb_test_no_output "set follow-exec-mode new"
> 

Done.

> (again, omitting the test name makes it default to the command)
> 
> I'd suggest replacing
> 
>     gdb_test_multiple "info prog" "info prog" {
> 	-i "$gdb_spawn_id" eof {
> 	    fail "info prog"
> 	}
> 	-i "$gdb_spawn_id" "No selected thread\."  {
> 	    pass "info prog"
> 	}
>     }
> 
> with the simpler
> 
>     gdb_test "info prog" "No selected thread."
> 
> If GDB crashes as it did before your fix, the test will be unresolved, which is
> treated the same as a FAIL.

Done.

> While at it, could you update the comment at the top of the file, which currently
> says:
> 
> # Check whether finish respects the print pretty user setting when printing the
> # function result.
> 

Done.

Also, I realized that by using runto_main at the start, I could replace
gdb_run_cmd/gdb_expect with a regular gdb_test continue.

Committed as attached.

Thanks,
- Tom

[-- Attachment #2: 0001-gdb-testsuite-Rewrite-catch-follow-exec.exp-using-gdb_test.patch --]
[-- Type: text/x-patch, Size: 3223 bytes --]

[gdb/testsuite]	Rewrite catch-follow-exec.exp using gdb_test

The testcase catch-follow-exec.exp is written use gdb -batch in order to avoid
a GDB SIGTTOU.  After the commit of "Avoid GDB SIGTTOU on catch exec + set
follow-exec-mode new (PR 23368)", that no longer is necessary.

Rewrite the test using regular gdb_test commands.

Tested with x86_64-linux.

2018-10-24  Tom de Vries  <tdevries@suse.de>

	* gdb.base/catch-follow-exec.exp: Rewrite using gdb_test.

---
 gdb/testsuite/gdb.base/catch-follow-exec.exp | 63 ++++++----------------------
 1 file changed, 13 insertions(+), 50 deletions(-)

diff --git a/gdb/testsuite/gdb.base/catch-follow-exec.exp b/gdb/testsuite/gdb.base/catch-follow-exec.exp
index c3c7c7ecdd..5f7db25265 100644
--- a/gdb/testsuite/gdb.base/catch-follow-exec.exp
+++ b/gdb/testsuite/gdb.base/catch-follow-exec.exp
@@ -13,72 +13,35 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-# Check whether finish respects the print pretty user setting when printing the
-# function result.
+# Test whether info prog crashes gdb at a catch point in follow-exec-mode new.
 
 standard_testfile
 
-if { [target_info gdb_protocol] != "" } {
-    # Even though the feature under features being tested are supported by
-    # gdbserver, the way this test is written doesn't make it easy with a
-    # remote target.
-    unsupported "not native"
-    return
-}
-
 if { ![remote_file target exists /bin/ls] } {
     unsupported "no ls"
     return
 }
 
-if { [build_executable "failed to prepare" $testfile $srcfile debug] == -1 } {
-    return -1
+if { [prepare_for_testing "failed to prepare" $testfile $srcfile debug] } {
+    return
 }
 
 proc catch_follow_exec { } {
-    global binfile
-    global gdb_spawn_id
-
-    set test "catch-follow-exec"
-
-    append FLAGS " \"$binfile\""
-    append FLAGS " -batch"
-    append FLAGS " -ex \"catch exec\""
-    append FLAGS " -ex \"set follow-exec-mode new\""
-    append FLAGS " -ex \"run\""
-    append FLAGS " -ex \"info prog\""
-
-    gdb_exit
-    if {[gdb_spawn_with_cmdline_opts "$FLAGS"] != 0} {
-	fail "spawn"
-	return
+    if { ![runto_main] } {
+	untested "could not run to main"
+	return -1
     }
 
-    gdb_test_multiple "" "run til exit" {
-	"runtime error:" {
-	    # Error in case of --enable-ubsan
-	    fail "no runtime error"
-	}
-	eof {
-	    set result [wait -i $gdb_spawn_id]
-	    verbose $result
+    gdb_test "catch exec" \
+	{Catchpoint [0-9]+ \(exec\)}
 
-	    gdb_assert { [lindex $result 2] == 0 }
+    gdb_test_no_output "set follow-exec-mode new"
 
-	    # We suspect this will be zero instead of one after fixing PR23368
-	    # - "gdb goes to into background when hitting exec catchpoint with
-	    # follow-exec-mode new"
-	    gdb_assert { [lindex $result 3] != 0 }
+    gdb_test "continue" \
+	".*hit Catchpoint.*"
 
-	    # Error in case of --disable-ubsan, we get
-	    # "CHILDKILLED SIGSEGV {segmentation violation}" as extra
-	    # argument(s).
-	    gdb_assert { [llength $result] == 4 }
-	}
-
-	remote_close host
-	clear_gdb_spawn_id
-    }
+    gdb_test "info prog" \
+	"No selected thread."
 }
 
 catch_follow_exec