gdb/testsuite/gdb.base/catch-fork-kill.exp

   1 # Copyright 2016-2023 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 # When we intercept a fork/vfork with a catchpoint, the child is left
  17 # stopped.  At that point, if we kill the parent, we should kill the
  18 # child as well.  This test makes sure that works.  See PR gdb/19494.
  19
  20 # The main idea of the test is make sure that when the program stops
  21 # for a fork catchpoint, and the user kills the parent, gdb also kills
  22 # the unfollowed fork child.  Since the child hasn't been added as an
  23 # inferior at that point, we need some other portable way to detect
  24 # that the child is gone.  The test uses a pipe for that.  The program
  25 # forks twice, so you have grandparent, child and grandchild.  The
  26 # grandchild inherits the write side of the pipe.  The grandparent
  27 # hangs reading from the pipe, since nothing ever writes to it.  If,
  28 # when GDB kills the child, it also kills the grandchild, then the
  29 # grandparent's pipe read returns 0/EOF and the test passes.
  30 # Otherwise, if GDB doesn't kill the grandchild, then the pipe read
  31 # never returns and the test times out.
  32
  33 standard_testfile
  34
  35 # Build two programs -- one for fork, and another for vfork.
  36 set testfile_fork "${testfile}-fork"
  37 set testfile_vfork "${testfile}-vfork"
  38
  39 foreach kind {"fork" "vfork"} {
  40     set compile_options "debug additional_flags=-DFORK=$kind"
  41     set testfile [set testfile_$kind]
  42     if {[build_executable $testfile.exp $testfile ${srcfile} \
  43              ${compile_options}] == -1} {
  44         untested "failed to compile"
  45         return -1
  46     }
  47 }
  48
  49 # The test proper.  FORK_KIND is either "fork" or "vfork".  EXIT_KIND
  50 # is either "exit" (run the parent to exit) or "kill" (kill parent).
  51
  52 proc do_test {fork_kind exit_kind} {
  53     global testfile testfile_$fork_kind
  54
  55     set testfile [set testfile_$fork_kind]
  56
  57     with_test_prefix "$fork_kind" {
  58         clean_restart $testfile
  59
  60         if ![runto_main] {
  61             return -1
  62         }
  63
  64         gdb_test_no_output "set follow-fork child"
  65         gdb_test_no_output "set detach-on-fork off"
  66
  67         gdb_test "catch $fork_kind" "Catchpoint .*($fork_kind).*"
  68
  69         gdb_test "continue" \
  70             "Catchpoint \[0-9\]* \\(${fork_kind}ed process \[0-9\]*\\),.*" \
  71             "continue to child ${fork_kind}"
  72
  73         gdb_test "continue" \
  74             "Catchpoint \[0-9\]* \\(${fork_kind}ed process \[0-9\]*\\),.*" \
  75             "continue to grandchild ${fork_kind}"
  76
  77         gdb_test "kill inferior 2" "" "kill child"
  78
  79         gdb_test "inferior 1" "Switching to inferior 1 .*" "switch to parent"
  80
  81         if {$exit_kind == "exit"} {
  82             gdb_test "break grandparent_done" "Breakpoint .*"
  83             gdb_test "continue" "hit Breakpoint .*, grandparent_done.*"
  84         } elseif {$exit_kind == "kill"} {
  85             gdb_test "kill" "" "kill parent" \
  86                 "Kill the program being debugged.*y or n. $" "y"
  87         } else {
  88             perror "unreachable"
  89         }
  90     }
  91 }
  92
  93 foreach_with_prefix fork-kind {"fork" "vfork"} {
  94     foreach_with_prefix exit-kind {"exit" "kill"} {
  95         do_test ${fork-kind} ${exit-kind}
  96     }
  97 }