--- /dev/null
+# This testcase is part of GDB, the GNU debugger.
+
+# Copyright 2004 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+# Check that GDB can and only executes single instructions when
+# stepping through a sequence of breakpoints interleaved by a signal
+# handler.
+
+# This test is known to tickle the following problems: kernel letting
+# the inferior execute both the system call, and the instruction
+# following, when single-stepping a system call; kernel failing to
+# propogate the single-step state when single-stepping the sigreturn
+# system call, instead resuming the inferior at full speed; GDB
+# doesn't know how to software single-step across a sigreturn
+# instruction. Since the kernel problems can be "fixed" using
+# software single-step this is KFAILed rather than XFAILed.
+
+if $tracelevel {
+ strace $tracelevel
+}
+
+set prms_id 0
+set bug_id 0
+
+set testfile "sigbpt"
+set srcfile ${testfile}.c
+set binfile ${objdir}/${subdir}/${testfile}
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
+ gdb_suppress_entire_file "Testcase compile failed, so all tests in this file will automatically fail."
+}
+
+gdb_exit
+gdb_start
+gdb_reinitialize_dir $srcdir/$subdir
+gdb_load ${binfile}
+
+#
+# Run to `main' where we begin our tests.
+#
+
+if ![runto_main] then {
+ gdb_suppress_tests
+}
+
+# If we can examine what's at memory address 0, it is possible that we
+# could also execute it. This could probably make us run away,
+# executing random code, which could have all sorts of ill effects,
+# especially on targets without an MMU. Don't run the tests in that
+# case.
+
+send_gdb "x 0\n"
+gdb_expect {
+ -re "0x0:.*Cannot access memory at address 0x0.*$gdb_prompt $" { }
+ -re "0x0:.*Error accessing memory address 0x0.*$gdb_prompt $" { }
+ -re ".*$gdb_prompt $" {
+ untested "Memory at address 0 is possibly executable"
+ return
+ }
+}
+
+gdb_test "break keeper"
+
+# Run to bowler, and then single step until there's a SIGSEGV. Record
+# the address of each single-step instruction (up to and including the
+# instruction that causes the SIGSEGV) in bowler_addrs, and the address
+# of the actual SIGSEGV in segv_addr.
+
+set bowler_addrs bowler
+gdb_test {display/i $pc}
+gdb_test "advance *bowler" "bowler.*" "advance to the bowler"
+set test "stepping to SIGSEGV"
+gdb_test_multiple "stepi" "$test" {
+ -re "Program received signal SIGSEGV.*pc *(0x\[0-9a-f\]*).*$gdb_prompt $" {
+ set segv_addr $expect_out(1,string)
+ pass "$test"
+ }
+ -re " .*pc *(0x\[0-9a-f\]*).*bowler.*$gdb_prompt $" {
+ set bowler_addrs [concat $expect_out(1,string) $bowler_addrs]
+ send_gdb "stepi\n"
+ exp_continue
+ }
+}
+
+# Now record the address of the instruction following the faulting
+# instruction in bowler_addrs.
+
+set test "get insn after fault"
+gdb_test_multiple {x/2i $pc} "$test" {
+ -re "(0x\[0-9a-f\]*).*bowler.*(0x\[0-9a-f\]*).*bowler.*$gdb_prompt $" {
+ set bowler_addrs [concat $expect_out(2,string) $bowler_addrs]
+ pass "$test"
+ }
+}
+
+# Procedures for returning the address of the instruction before, at
+# and after, the faulting instruction.
+
+proc before_segv { } {
+ global bowler_addrs
+ return [lindex $bowler_addrs 2]
+}
+
+proc at_segv { } {
+ global bowler_addrs
+ return [lindex $bowler_addrs 1]
+}
+
+proc after_segv { } {
+ global bowler_addrs
+ return [lindex $bowler_addrs 0]
+}
+
+# Check that the address table and SIGSEGV correspond.
+
+set test "Verify that SIGSEGV occurs at the last STEPI insn"
+if {[string compare $segv_addr [at_segv]] == 0} {
+ pass "$test"
+} else {
+ fail "$test ($segv_addr [at_segv])"
+}
+
+# Check that the inferior is correctly single stepped all the way back
+# to a faulting instruction.
+
+proc stepi_out { name args } {
+ global gdb_prompt
+
+ # Set SIGSEGV to pass+nostop and then run the inferior all the way
+ # through to the signal handler. With the handler is reached,
+ # disable SIGSEGV, ensuring that further signals stop the
+ # inferior. Stops a SIGSEGV infinite loop when a broke system
+ # keeps re-executing the faulting instruction.
+ rerun_to_main
+ gdb_test "handle SIGSEGV nostop print pass" "" "pass SIGSEGV; $name"
+ gdb_test "continue" "keeper.*" "continue to keeper; $name"
+ gdb_test "handle SIGSEGV stop print nopass" "" "nopass SIGSEGV; $name"
+
+ # Insert all the breakpoints. To avoid the need to step over
+ # these instructions, this is delayed until after the keeper has
+ # been reached.
+ for {set i 0} {$i < [llength $args]} {incr i} {
+ gdb_test "break [lindex $args $i]" "Breakpoint.*" \
+ "set breakpoint $i of [llength $args]; $name"
+ }
+
+ # Single step our way out of the keeper, through the signal
+ # trampoline, and back to the instruction that faulted.
+ set test "stepi out of handler; $name"
+ gdb_test_multiple "stepi" "$test" {
+ -re "keeper.*$gdb_prompt $" {
+ send_gdb "stepi\n"
+ exp_continue
+ }
+ -re "signal handler.*$gdb_prompt $" {
+ send_gdb "stepi\n"
+ exp_continue
+ }
+ -re "Program received signal SIGSEGV.*$gdb_prompt $" {
+ kfail gdb/1702 "$test (executed fault insn)"
+ }
+ -re "Breakpoint.*pc *[at_segv] .*bowler.*$gdb_prompt $" {
+ pass "$test (at breakpoint)"
+ }
+ -re "Breakpoint.*pc *[after_segv] .*bowler.*$gdb_prompt $" {
+ kfail gdb/1702 "$test (executed breakpoint)"
+ }
+ -re "pc *[at_segv] .*bowler.*$gdb_prompt $" {
+ pass "$test"
+ }
+ -re "pc *[after_segv] .*bowler.*$gdb_prompt $" {
+ kfail gdb/1702 "$test (skipped fault insn)"
+ }
+ }
+
+ # Clear any breakpoints
+ for {set i 0} {$i < [llength $args]} {incr i} {
+ gdb_test "clear [lindex $args $i]" "Deleted .*" \
+ "clear breakpoint $i of [llength $args]; $name"
+ }
+}
+
+# Let a signal handler exit, returning to a breakpoint instruction
+# inserted at the original fault instruction. Check that the
+# breakpoint is hit, and that single stepping off that breakpoint
+# executes the underlying fault instruction causing a SIGSEGV.
+
+proc cont_out { name args } {
+ global gdb_prompt
+
+ # Set SIGSEGV to pass+nostop and then run the inferior all the way
+ # through to the signal handler. With the handler is reached,
+ # disable SIGSEGV, ensuring that further signals stop the
+ # inferior. Stops a SIGSEGV infinite loop when a broke system
+ # keeps re-executing the faulting instruction.
+ rerun_to_main
+ gdb_test "handle SIGSEGV nostop print pass" "" "pass SIGSEGV; $name"
+ gdb_test "continue" "keeper.*" "continue to keeper; $name"
+ gdb_test "handle SIGSEGV stop print nopass" "" "nopass SIGSEGV; $name"
+
+ # Insert all the breakpoints. To avoid the need to step over
+ # these instructions, this is delayed until after the keeper has
+ # been reached. Always set a breakpoint at the signal trampoline
+ # instruction.
+ set args [concat $args "*[at_segv]"]
+ for {set i 0} {$i < [llength $args]} {incr i} {
+ gdb_test "break [lindex $args $i]" "Breakpoint.*" \
+ "set breakpoint $i of [llength $args]; $name"
+ }
+
+ # Let the handler return, it should "appear to hit" the breakpoint
+ # inserted at the faulting instruction. Note that the breakpoint
+ # instruction wasn't executed, rather the inferior was SIGTRAPed
+ # with the PC at the breakpoint.
+ gdb_test "continue" "Breakpoint.*pc *[at_segv] .*" \
+ "continue to breakpoint at fault; $name"
+
+ # Now single step the faulted instrction at that breakpoint.
+ gdb_test "stepi" \
+ "Program received signal SIGSEGV.*pc *[at_segv] .*" \
+ "stepi fault; $name"
+
+ # Clear any breakpoints
+ for {set i 0} {$i < [llength $args]} {incr i} {
+ gdb_test "clear [lindex $args $i]" "Deleted .*" \
+ "clear breakpoint $i of [llength $args]; $name"
+ }
+
+}
+
+
+
+# Try to confuse DECR_PC_AFTER_BREAK architectures by scattering
+# breakpoints around the faulting address. In all cases the inferior
+# should single-step out of the signal trampoline halting (but not
+# executing) the fault instruction.
+
+stepi_out "stepi"
+stepi_out "stepi bp before segv" "*[before_segv]"
+stepi_out "stepi bp at segv" "*[at_segv]"
+stepi_out "stepi bp before and at segv" "*[at_segv]" "*[before_segv]"
+
+
+# Try to confuse DECR_PC_AFTER_BREAK architectures by scattering
+# breakpoints around the faulting address. In all cases the inferior
+# should exit the signal trampoline halting at the breakpoint that
+# replaced the fault instruction.
+cont_out "cont"
+cont_out "cont bp after segv" "*[before_segv]"
+cont_out "cont bp before and after segv" "*[before_segv]" "*[after_segv]"
projects / external / binutils.git / commitdiff