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