1 # This testcase is part of GDB, the GNU debugger.
3 # Copyright 2017-2023 Free Software Foundation, Inc.
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6 # it under the terms of the GNU General Public License as published by
7 # the Free Software Foundation; either version 3 of the License, or
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10 # This program is distributed in the hope that it will be useful,
11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 # GNU General Public License for more details.
15 # You should have received a copy of the GNU General Public License
16 # along with this program. If not, see <http://www.gnu.org/licenses/>.
18 # This testcase exercises GDB's terminal ownership management
19 # (terminal_ours/terminal_inferior, etc.) when debugging multiple
20 # inferiors. It tests debugging multiple inferiors started with
21 # different combinations of 'run'/'run+tty'/'attach', and ensures that
22 # the process that is sharing GDB's terminal/session is properly made
23 # the GDB terminal's foregound process group (i.e., "given the
28 if ![can_spawn_for_attach] {
32 if [build_executable "failed to prepare" $testfile $srcfile {debug}] {
36 # Start the programs running and then wait for a bit, to be sure that
37 # they can be attached to. We start these processes upfront in order
38 # to reuse them for the different iterations. This makes the testcase
39 # faster, compared to calling spawn_wait_for_attach for each iteration
40 # in the testing matrix.
42 set spawn_id_list [spawn_wait_for_attach [list $binfile $binfile]]
43 set attach_spawn_id1 [lindex $spawn_id_list 0]
44 set attach_spawn_id2 [lindex $spawn_id_list 1]
45 set attach_pid1 [spawn_id_get_pid $attach_spawn_id1]
46 set attach_pid2 [spawn_id_get_pid $attach_spawn_id2]
48 # Create inferior WHICH_INF. INF_HOW is how to create it. This can
51 # - "run" - for "run" command.
52 # - "tty" - for "run" + "tty TTY".
53 # - "attach" - for attaching to an existing process.
54 proc create_inferior {which_inf inf_how} {
57 # Run to main and delete breakpoints.
58 proc my_runto_main {} {
62 # Delete breakpoints otherwise GDB would try to step over
63 # the breakpoint at 'main' without resuming the other
64 # inferior, possibly masking the issue we're trying to
71 if {$inf_how == "run"} {
73 global inferior_spawn_id
74 return $inferior_spawn_id
76 } elseif {$inf_how == "tty"} {
77 # Create the new PTY for the inferior.
79 set inf_spawn_id $spawn_id
80 set inf_tty_name $spawn_out(slave,name)
81 gdb_test_no_output "tty $inf_tty_name" "tty TTY"
86 } elseif {$inf_how == "attach"} {
88 # Reuse the inferiors spawned at the start of the testcase (to
89 # avoid having to wait the delay imposed by
90 # spawn_wait_for_attach).
91 global attach_spawn_id$which_inf
92 set test_spawn_id [set attach_spawn_id$which_inf]
93 set testpid [spawn_id_get_pid $test_spawn_id]
94 if {[gdb_test "attach $testpid" \
95 "Attaching to program: .*, process $testpid.*(in|at).*" \
98 # The program is now stopped, but if testing against
99 # gdbserver, then the inferior's output emmitted before it
100 # stopped isn't flushed unless we explicitly do so,
101 # because it is on a different spawn_id. Do it now, to
102 # avoid confusing tests further below.
103 gdb_test_multiple "" "flush inferior output" {
105 -i $test_spawn_id -re "pid=" {
113 return $test_spawn_id
116 error "unhandled inf_how: $inf_how"
122 # Print debug output.
124 proc send_debug {str} {
125 # Uncomment for debugging.
129 # The core of the testcase. See intro. Creates two inferiors that
130 # both loop changing their terminal's settings and printing output,
131 # and checks whether they receive SIGTTOU. INF1_HOW and INF2_HOW
132 # indicate how inferiors 1 and 2 should be created, respectively. See
133 # 'create_inferior' above for what arguments these parameters accept.
135 proc coretest {inf1_how inf2_how} {
137 global inferior_spawn_id
141 clean_restart $binfile
143 with_test_prefix "inf1" {
144 set inf1_spawn_id [create_inferior 1 $inf1_how]
148 gdb_test "add-inferior" "Added inferior $num.*" \
149 "add empty inferior $num"
150 gdb_test "inferior $num" "Switching to inferior $num.*" \
151 "switch to inferior $num"
152 gdb_file_cmd ${binfile}
154 with_test_prefix "inf2" {
155 set inf2_spawn_id [create_inferior 2 $inf2_how]
158 gdb_test_no_output "set schedule-multiple on"
160 # "run" makes each inferior be a process group leader. When we
161 # run both inferiors in GDB's terminal/session, only one can end
162 # up as the terminal's foreground process group, so it's expected
163 # that the other receives a SIGTTOU.
164 set expect_ttou [expr {$inf1_how == "run" && $inf2_how == "run"}]
173 set test "info inferiors"
174 gdb_test_multiple $test $test {
175 -re "1${any}process ($decimal)${any}\r\n" {
176 set pid1 $expect_out(1,string)
177 send_debug "pid1=$pid1\n"
180 -re "2${any}process ($decimal)${any}\r\n" {
181 set pid2 $expect_out(1,string)
182 send_debug "pid2=$pid2\n"
185 -re "$gdb_prompt $" {
190 # Helper for the gdb_test_multiple call below. Issues a PASS if
191 # we've seen each inferior print at least 3 times, otherwise
192 # continues waiting for inferior output.
193 proc pass_or_exp_continue {} {
195 if {$count1 >= 3 && $count2 >= 3} {
197 fail "$gdb_test_name (expected SIGTTOU)"
207 set infs_spawn_ids [list $inf1_spawn_id $inf2_spawn_id]
208 send_debug "infs_spawn_ids=$infs_spawn_ids\n"
213 # We're going to interrupt with Ctrl-C. For this to work we must
214 # be sure to consume the "Continuing." message first, or GDB may
215 # still own the terminal. Also, note that in the attach case, we
216 # flushed inferior output right after attaching, so that we're
217 # sure that the "pid=" lines we see are emitted by the inferior
218 # after it is continued, instead of having been emitted before it
220 gdb_test_multiple "continue" "continue, hand over terminal" {
226 gdb_test_multiple "" "continue" {
227 -i $infs_spawn_ids -re "pid=$pid1, count=" {
231 -i $infs_spawn_ids -re "pid=$pid2, count=" {
235 -i $gdb_spawn_id -re "received signal SIGTTOU.*$gdb_prompt " {
237 pass "$gdb_test_name (expected SIGTTOU)"
239 fail "$gdb_test_name (SIGTTOU)"
246 gdb_test "" "Quit" "stop with control-c (Quit)"
248 gdb_test "" "received signal SIGINT.*" "stop with control-c (SIGINT)"
251 # Useful for debugging in case the Ctrl-C above fails.
252 with_test_prefix "final" {
253 gdb_test "info inferiors"
254 gdb_test "info threads"
258 set how_modes {"run" "attach" "tty"}
260 foreach_with_prefix inf1_how $how_modes {
261 foreach_with_prefix inf2_how $how_modes {
262 if {($inf1_how == "tty" || $inf2_how == "tty")
263 && [target_info gdb_protocol] == "extended-remote"} {
264 # No way to specify the inferior's tty in the remote
266 unsupported "no support for \"tty\" in the RSP"
270 coretest $inf1_how $inf2_how
274 kill_wait_spawned_process $attach_spawn_id1
275 kill_wait_spawned_process $attach_spawn_id2