gdb/testsuite/gdb.base/signull.exp

   1 # This testcase is part of GDB, the GNU debugger.
   2
   3 # Copyright 2004, 2005, 2007, 2008, 2009, 2010, 2011
   4 # Free Software Foundation, Inc.
   5
   6 # This program is free software; you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation; either version 3 of the License, or
   9 # (at your option) any later version.
  10 #
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU General Public License
  17 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18
  19 # Check that GDB can trigger and backtrace SIGSEGV signal stacks
  20 # caused by both accessing (data) and executing (code) at address
  21 # zero.
  22
  23 # On function descriptor architectures, a zero descriptor, instead of
  24 # a NULL pointer, is used.  That way the NULL code test always
  25 # contains a zero code reference.
  26
  27 # For recovery, sigjmp/longjmp are used.
  28
  29 # This also tests backtrace/gdb1476.
  30
  31 if [target_info exists gdb,nosignals] {
  32     verbose "Skipping signull.exp because of nosignals."
  33     continue
  34 }
  35
  36 if $tracelevel {
  37     strace $tracelevel
  38 }
  39
  40
  41 set testfile "signull"
  42 set srcfile ${testfile}.c
  43 set binfile ${objdir}/${subdir}/${testfile}
  44 if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
  45     untested signull.exp
  46     return -1
  47 }
  48
  49 gdb_exit
  50 gdb_start
  51 gdb_reinitialize_dir $srcdir/$subdir
  52 gdb_load ${binfile}
  53
  54 #
  55 # Run to `main' where we begin our tests.
  56 #
  57
  58 if ![runto_main] then {
  59     gdb_suppress_tests
  60 }
  61
  62 # If we can examine what's at memory address 0, it is possible that we
  63 # could also execute it.  This could probably make us run away,
  64 # executing random code, which could have all sorts of ill effects,
  65 # especially on targets without an MMU.  Don't run the tests in that
  66 # case.
  67
  68 gdb_test_multiple "x 0" "memory at address 0" {
  69     -re "0x0:.*Cannot access memory at address 0x0.*$gdb_prompt $" { }
  70     -re "0x0:.*Error accessing memory address 0x0.*$gdb_prompt $" { }
  71     -re ".*$gdb_prompt $" {
  72         untested "Memory at address 0 is possibly executable"
  73         return
  74     }
  75 }
  76
  77 # If an attempt to call a NULL pointer leaves the inferior in main,
  78 # then function pointers are descriptors, probe this and remember the
  79 # result.
  80
  81 gdb_test_no_output "set test = code_entry_point" \
  82     "set for function pointer probe"
  83 set test "probe function pointer"
  84 set function_pointer code_entry_point
  85 set signame "SIGSEGV"
  86 gdb_test_multiple "continue" "$test" {
  87     -re "Program received signal SIGSEGV.*bowler .*$gdb_prompt $" {
  88         set function_pointer code_descriptor
  89         pass "$test (function descriptor)"
  90     }
  91     -re "Program received signal SIGSEGV.*0.*$gdb_prompt $" {
  92         pass "$test (function entry-point)"
  93     }
  94     -re "Program received signal SIGBUS.*0.*$gdb_prompt $" {
  95         set signame SIGBUS
  96         pass "$test (function entry-point)"
  97     }
  98 }
  99
 100 # Re-start from scratch, breakpoint the bowler so that control is
 101 # regained after each test, and run up to that.
 102 rerun_to_main
 103 gdb_test "break bowler"
 104 gdb_test "break keeper"
 105 # By default Stop:Yes Print:Yes Pass:Yes
 106 gdb_test "handle SIGSEGV" "SIGSEGV.*Yes.*Yes.*Yes.*Segmentation fault"
 107 gdb_test "handle SIGBUS" "SIGBUS.*Yes.*Yes.*Yes.*Bus error"
 108
 109 # For the given signal type, check that: the SIGSEGV occures; a
 110 # backtrace from the SEGV works; the sigsegv is delivered; a backtrace
 111 # through the SEGV works.
 112
 113 proc test_segv { name tag bt_from_segv bt_from_keeper } {
 114     global signame
 115     gdb_test continue "Breakpoint.* bowler.*" "${name}; start with the bowler"
 116     # NB: Don't use $tag in the testname - changes across systems.
 117     gdb_test_no_output "set test = $tag" "${name}; select the pointer type"
 118     gdb_test continue "Program received signal ${signame}.*" \
 119         "${name}; take the ${signame}"
 120     gdb_test backtrace $bt_from_segv "${name}; backtrace from ${signame}"
 121     gdb_test continue "Breakpoint.* keeper.*" "${name}; continue to the keeper"
 122     gdb_test backtrace $bt_from_keeper "${name}; backtrace from keeper through ${signame}"
 123 }
 124
 125 test_segv "data read" data_read \
 126     {#0 .* bowler .*#1  .* main .*} \
 127     {#0 .* keeper .*#1  .* handler .*#2 .* bowler .*#3  .* main .*}
 128 test_segv "data write" data_write \
 129     {#0 .* bowler .*#1  .* main .*} \
 130     {#0 .* keeper .*#1  .* handler .*#2 .* bowler .*#3  .* main .*}
 131 test_segv code $function_pointer \
 132     {#0 .* 0x0+ .*#1 .* bowler .*#2  .* main .*} \
 133     {#0 .* keeper .*#1  .* handler .*#2 .* 0x0+ .*#3 .* bowler .*#4 .* main .*}