xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/testsuite/gdb.base/foll-fork.exp (revision 2718af68c3efc72c9769069b5c7f9ed36f6b9def)
1#   Copyright 1997-2019 Free Software Foundation, Inc.
2
3# This program is free software; you can redistribute it and/or modify
4# it under the terms of the GNU General Public License as published by
5# the Free Software Foundation; either version 3 of the License, or
6# (at your option) any later version.
7#
8# This program is distributed in the hope that it will be useful,
9# but WITHOUT ANY WARRANTY; without even the implied warranty of
10# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11# GNU General Public License for more details.
12#
13# You should have received a copy of the GNU General Public License
14# along with this program.  If not, see <http://www.gnu.org/licenses/>.
15
16# Until "set follow-fork-mode" and "catch fork" are implemented on
17# other targets...
18#
19if { ![istarget "*-*-linux*"] && ![istarget "*-*-openbsd*"] } then {
20    continue
21}
22
23standard_testfile
24
25if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} {
26    return -1
27}
28
29proc check_fork_catchpoints {} {
30  global gdb_prompt
31
32  # Verify that the system supports "catch fork".
33  gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" "insert first fork catchpoint"
34  set has_fork_catchpoints 0
35  gdb_test_multiple "continue" "continue to first fork catchpoint" {
36    -re ".*Your system does not support this type\r\nof catchpoint.*$gdb_prompt $" {
37      unsupported "continue to first fork catchpoint"
38    }
39    -re ".*Catchpoint.*$gdb_prompt $" {
40      set has_fork_catchpoints 1
41      pass "continue to first fork catchpoint"
42    }
43  }
44
45  if {$has_fork_catchpoints == 0} {
46    unsupported "fork catchpoints"
47    return -code return
48  }
49}
50
51# Test follow-fork to ensure that the correct process is followed, that
52# the followed process stops where it is expected to stop, that processes
53# are detached (or not) as expected, and that the inferior list has the
54# expected contents after following the fork.  WHO is the argument to
55# the 'set follow-fork-mode' command, DETACH is the argument to the
56# 'set detach-on-fork' command, and CMD is the GDB command used to
57# execute the program past the fork.  If the value of WHO or DETACH is
58# 'default', the corresponding GDB command is skipped for that test.
59# The value of CMD must be either 'next 2' or 'continue'.
60proc test_follow_fork { who detach cmd } {
61    global gdb_prompt
62    global srcfile
63    global testfile
64
65    with_test_prefix "follow $who, detach $detach, command \"$cmd\"" {
66
67	# Start a new debugger session each time so defaults are legitimate.
68	clean_restart $testfile
69
70	if ![runto_main] {
71	    untested "could not run to main"
72	    return -1
73	}
74
75	# The "Detaching..." and "Attaching..." messages may be hidden by
76	# default.
77	gdb_test_no_output "set verbose"
78
79	# Set follow-fork-mode if we aren't using the default.
80	if {$who == "default"} {
81	    set who "parent"
82	} else {
83	    gdb_test_no_output "set follow-fork $who"
84	}
85
86	gdb_test "show follow-fork" \
87	"Debugger response to a program call of fork or vfork is \"$who\"." \
88	"show follow-fork"
89
90	# Set detach-on-fork mode if we aren't using the default.
91	if {$detach == "default"} {
92	    set detach "on"
93	} else {
94	    gdb_test_no_output "set detach-on-fork $detach"
95	}
96
97	gdb_test "show detach-on-fork" \
98		 "Whether gdb will detach.* fork is $detach." \
99		 "show detach-on-fork"
100
101	# Set a breakpoint after the fork if we aren't single-stepping
102	# past the fork.
103	if {$cmd == "continue"} {
104	    set bp_after_fork [gdb_get_line_number "set breakpoint here"]
105	    gdb_test "break ${srcfile}:$bp_after_fork" \
106		     "Breakpoint.*, line $bp_after_fork.*" \
107		     "set breakpoint after fork"
108	}
109
110	# Set up the output we expect to see after we run.
111	set expected_re ""
112	if {$who == "child"} {
113	    set expected_re "\\\[Attaching after.* fork to.*"
114	    if {$detach == "on"} {
115		append expected_re "\\\[Detaching after fork from .*"
116	    }
117	    append expected_re "set breakpoint here.*"
118	} elseif {$who == "parent" && $detach == "on"} {
119	    set expected_re "\\\[Detaching after fork from .*set breakpoint here.*"
120	} else {
121	    set expected_re ".*set breakpoint here.*"
122	}
123
124	# Test running past and following the fork, using the parameters
125	# set above.
126	gdb_test $cmd $expected_re "$cmd past fork"
127
128	# Check that we have the inferiors arranged correctly after
129	# following the fork.
130	set resume_unfollowed 0
131	if {$who == "parent" && $detach == "on"} {
132
133	    # Follow parent / detach child: the only inferior is the parent.
134	    gdb_test "info inferiors" "\\* 1 .* process.*" \
135		     "info inferiors"
136
137	} elseif {$who == "parent" && $detach == "off"} {
138
139	    # Follow parent / keep child: two inferiors under debug, the
140	    # parent is the current inferior.
141	    gdb_test "info inferiors" "\\* 1 .*process.* 2 .*process.*" \
142		     "info inferiors"
143
144	    gdb_test "inferior 2" "Switching to inferior 2 .*"
145	    set resume_unfollowed 1
146
147	} elseif {$who == "child" && $detach == "on"} {
148
149	    # Follow child / detach parent: the child is under debug and is
150	    # the current inferior.  The parent is listed but is not under
151	    # debug.
152	    gdb_test "info inferiors" " 1 .*<null>.*\\* 2 .*process.*" \
153		     "info inferiors"
154
155	} elseif {$who == "child" && $detach == "off"} {
156
157	    # Follow child / keep parent: two inferiors under debug, the
158	    # child is the current inferior.
159	    gdb_test "info inferiors" " 1 .*process.*\\* 2 .*process.*" \
160		     "info inferiors"
161
162	    gdb_test "inferior 1" "Switching to inferior 1 .*"
163	    set resume_unfollowed 1
164	}
165
166	if {$resume_unfollowed == 1} {
167	    if {$cmd == "next 2"} {
168
169		gdb_continue_to_end "continue unfollowed inferior to end"
170
171	    } elseif {$cmd == "continue"} {
172
173		gdb_continue_to_breakpoint \
174		    "continue unfollowed inferior to bp" \
175		    ".* set breakpoint here.*"
176	    }
177	}
178    }
179}
180
181proc catch_fork_child_follow {} {
182    global gdb_prompt
183    global srcfile
184
185    set bp_after_fork [gdb_get_line_number "set breakpoint here"]
186
187    gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" \
188	"explicit child follow, set catch fork"
189
190    # Verify that the catchpoint is mentioned in an "info breakpoints",
191    # and further that the catchpoint mentions no process id.
192    #
193    set test_name "info shows catchpoint without pid"
194    gdb_test_multiple "info breakpoints" "$test_name" {
195	-re ".*catchpoint.*keep y.*fork\[\r\n\]+$gdb_prompt $" {
196	    pass "$test_name"
197	}
198    }
199
200    gdb_test "continue" \
201	"Catchpoint \[0-9\]* \\(forked process \[0-9\]*\\),.*" \
202	"explicit child follow, catch fork"
203
204    # Verify that the catchpoint is mentioned in an "info breakpoints",
205    # and further that the catchpoint managed to capture a process id.
206    #
207    set test_name "info shows catchpoint without pid"
208    gdb_test_multiple "info breakpoints" "$test_name" {
209	-re ".*catchpoint.*keep y.*fork, process.*$gdb_prompt $" {
210	    pass "$test_name"
211	}
212    }
213
214    gdb_test_no_output "set follow-fork child"
215
216    gdb_test "tbreak ${srcfile}:$bp_after_fork" \
217	"Temporary breakpoint.*, line $bp_after_fork.*" \
218	"set follow-fork child, tbreak"
219
220    set expected_re "\\\[Attaching after.* fork to.*\\\[Detaching after fork from"
221    append expected_re ".* at .*$bp_after_fork.*"
222    gdb_test "continue" $expected_re "set follow-fork child, hit tbreak"
223
224    # The parent has been detached; allow time for any output it might
225    # generate to arrive, so that output doesn't get confused with
226    # any expected debugger output from a subsequent testpoint.
227    #
228    exec sleep 1
229
230    gdb_test "delete breakpoints" \
231	"" \
232	"set follow-fork child, cleanup" \
233	"Delete all breakpoints. \\(y or n\\) $" \
234	"y"
235}
236
237proc catch_fork_unpatch_child {} {
238    global gdb_prompt
239    global srcfile
240
241    set bp_exit [gdb_get_line_number "at exit"]
242
243    gdb_test "break callee" "file .*$srcfile, line .*" \
244	"unpatch child, break at callee"
245    gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" \
246	"unpatch child, set catch fork"
247
248    gdb_test "continue" \
249	"Catchpoint \[0-9\]* \\(forked process \[0-9\]*\\),.*" \
250	"unpatch child, catch fork"
251
252    # Delete all breakpoints and catchpoints.
253    delete_breakpoints
254
255    # Force $srcfile as the current GDB source can be in glibc sourcetree.
256    gdb_test "break $srcfile:$bp_exit" \
257	"Breakpoint .*file .*$srcfile, line .*" \
258	"unpatch child, breakpoint at exit call"
259
260    gdb_test_no_output "set follow-fork child" \
261	"unpatch child, set follow-fork child"
262
263    set test "unpatch child, unpatched parent breakpoints from child"
264    gdb_test_multiple "continue" $test {
265	-re "at exit.*$gdb_prompt $" {
266	    pass "$test"
267	}
268	-re "SIGTRAP.*$gdb_prompt $" {
269	    fail "$test"
270
271	    # Explicitly kill this child, so we can continue gracefully
272	    # with further testing...
273	    send_gdb "kill\n"
274	    gdb_expect {
275		-re ".*Kill the program being debugged.*y or n. $" {
276		    send_gdb "y\n"
277		    gdb_expect -re "$gdb_prompt $" {}
278		}
279	    }
280	}
281    }
282}
283
284proc tcatch_fork_parent_follow {} {
285    global gdb_prompt
286    global srcfile
287
288    set bp_after_fork [gdb_get_line_number "set breakpoint here"]
289
290    gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" \
291	"explicit parent follow, set tcatch fork"
292
293# ??rehrauer: I don't yet know how to get the id of the tcatch
294# via this script, so that I can add a -do list to it.  For now,
295# do the follow stuff after the catch happens.
296
297    gdb_test "continue" \
298	"Catchpoint \[0-9\]* \\(forked process \[0-9\]*\\),.*" \
299	"explicit parent follow, tcatch fork"
300
301    gdb_test_no_output "set follow-fork parent"
302
303    gdb_test "tbreak ${srcfile}:$bp_after_fork" \
304	"Temporary breakpoint.*, line $bp_after_fork.*" \
305	"set follow-fork parent, tbreak"
306
307    gdb_test "continue" \
308	"\\\[Detaching after fork from.* at .*$bp_after_fork.*" \
309	"set follow-fork parent, hit tbreak"
310
311    # The child has been detached; allow time for any output it might
312    # generate to arrive, so that output doesn't get confused with
313    # any expected debugger output from a subsequent testpoint.
314    #
315    exec sleep 1
316
317    gdb_test "delete breakpoints" \
318	"" \
319	"set follow-fork parent, cleanup" \
320	"Delete all breakpoints. \\(y or n\\) $" \
321	"y"
322}
323
324proc do_fork_tests {} {
325    global gdb_prompt
326    global testfile
327
328    # Verify that help is available for "set follow-fork-mode".
329    #
330    gdb_test "help set follow-fork-mode" \
331	"Set debugger response to a program call of fork or vfork..*
332A fork or vfork creates a new process.  follow-fork-mode can be:.*
333.*parent  - the original process is debugged after a fork.*
334.*child   - the new process is debugged after a fork.*
335The unfollowed process will continue to run..*
336By default, the debugger will follow the parent process..*" \
337	"help set follow-fork"
338
339    # Verify that we can set follow-fork-mode, using an abbreviation
340    # for both the flag and its value.
341    #
342    gdb_test_no_output "set follow-fork ch"
343
344    gdb_test "show follow-fork" \
345	"Debugger response to a program call of fork or vfork is \"child\".*" \
346	"set follow-fork, using abbreviations"
347
348    # Verify that we cannot set follow-fork-mode to nonsense.
349    #
350    gdb_test "set follow-fork chork" "Undefined item: \"chork\".*" \
351	"set follow-fork to nonsense is prohibited"
352
353    gdb_test_no_output "set follow-fork parent" "reset parent"
354
355    # Check that fork catchpoints are supported, as an indicator for whether
356    # fork-following is supported.
357    if [runto_main] then { check_fork_catchpoints }
358
359    # Test the basic follow-fork functionality using all combinations of
360    # values for follow-fork-mode and detach-on-fork, using either a
361    # breakpoint or single-step to execute past the fork.
362    #
363    # The first loop should be sufficient to test the defaults.  There
364    # is no need to test using the defaults in other permutations (e.g.
365    # "default" "on", "parent" "default", etc.).
366    foreach cmd {"next 2" "continue"} {
367        test_follow_fork "default" "default" $cmd
368    }
369
370    # Now test all explicit permutations.
371    foreach who {"parent" "child"} {
372	foreach detach {"on" "off"} {
373	    foreach cmd {"next 2" "continue"} {
374		test_follow_fork $who $detach $cmd
375	    }
376	}
377    }
378
379    # Catchpoint tests.
380
381    # Restart to eliminate any effects of the follow-fork tests.
382    clean_restart $testfile
383    gdb_test_no_output "set verbose"
384
385    # Test the ability to catch a fork, specify that the child be
386    # followed, and continue.  Make the catchpoint permanent.
387    #
388    if [runto_main] then { catch_fork_child_follow }
389
390    # Test that parent breakpoints are successfully detached from the
391    # child at fork time, even if the user removes them from the
392    # breakpoints list after stopping at a fork catchpoint.
393    if [runto_main] then { catch_fork_unpatch_child }
394
395    # Test the ability to catch a fork, specify via a -do clause that
396    # the parent be followed, and continue.  Make the catchpoint temporary.
397    #
398    if [runto_main] then { tcatch_fork_parent_follow }
399}
400
401# This is a test of gdb's ability to follow the parent, child or both
402# parent and child of a Unix fork() system call.
403#
404do_fork_tests
405
406return 0
407