gdb/testsuite/gdb.base/sigstep.exp

   1 # Copyright 2004-2014 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
  17 # The program sigstep.c creates a very simple backtrace containing one
  18 # signal handler and signal trampoline.  A flag is set and then the
  19 # handler returns.  This is repeated at infinitum.
  20
  21 # This test runs the program up to the signal handler, and then
  22 # attempts to step/next out of the handler and back into main.
  23
  24 if [target_info exists gdb,nosignals] {
  25     verbose "Skipping sigstep.exp because of nosignals."
  26     continue
  27 }
  28
  29
  30 standard_testfile
  31
  32 if {[build_executable $testfile.exp $testfile $srcfile debug]} {
  33     untested $testfile.exp
  34     return -1
  35 }
  36
  37 set clear_done [gdb_get_line_number {done = 0}]
  38 set infinite_loop [gdb_get_line_number {while (!done)}]
  39
  40 # Restart GDB, set a display showing $PC, and run to main.
  41
  42 proc restart {} {
  43     global binfile
  44
  45     clean_restart $binfile
  46
  47     gdb_test "display/i \$pc"
  48
  49     runto_main
  50 }
  51
  52 # Pass all the alarms straight through (but verbosely)
  53 # gdb_test "handle SIGALRM print pass nostop"
  54 # gdb_test "handle SIGVTALRM print pass nostop"
  55 # gdb_test "handle SIGPROF print pass nostop"
  56
  57 # Run to the signal handler, validate the backtrace.
  58
  59 proc validate_backtrace {} {
  60     with_test_prefix "validate backtrace" {
  61         restart
  62
  63         gdb_test "break handler"
  64         gdb_test "continue" ".* handler .*" "continue to stepi handler"
  65         gdb_test_sequence "bt" "backtrace for nexti" {
  66             "\[\r\n\]+.0 \[^\r\n\]* handler "
  67             "\[\r\n\]+.1  .signal handler called."
  68             "\[\r\n\]+.2 \[^\r\n\]* main "
  69         }
  70     }
  71 }
  72
  73 validate_backtrace
  74
  75 proc advance { cmd } {
  76     global gdb_prompt inferior_exited_re
  77
  78     with_test_prefix "$cmd from handler" {
  79         restart
  80
  81         gdb_test "break handler"
  82
  83         # Get us into the handler
  84         gdb_test "continue" ".* handler .*" "continue to handler"
  85
  86         set test "leave handler"
  87         gdb_test_multiple "$cmd" "${test}" {
  88             -re "Could not insert single-step breakpoint.*$gdb_prompt $" {
  89                 setup_kfail gdb/8841 "sparc*-*-openbsd*"
  90                 fail "$test (could not insert single-step breakpoint)"
  91             }
  92             -re "done = 1;.*${gdb_prompt} $" {
  93                 send_gdb "$cmd\n"
  94                 exp_continue -continue_timer
  95             }
  96             -re "\} .. handler .*${gdb_prompt} $" {
  97                 send_gdb "$cmd\n"
  98                 exp_continue -continue_timer
  99             }
 100             -re "$inferior_exited_re normally.*${gdb_prompt} $" {
 101                 setup_kfail gdb/8744 powerpc-*-*bsd*
 102                 fail "$test (program exited)"
 103             }
 104             -re "(while ..done|done = 0).*${gdb_prompt} $" {
 105                 # After stepping out of a function /r signal-handler, GDB will
 106                 # advance the inferior until it is at the first instruction of
 107                 # a code-line.  While typically things return to the middle of
 108                 # the "while..." (and hence GDB advances the inferior to the
 109                 # "return..." line) it is also possible for the return to land
 110                 # on the first instruction of "while...".  Accept both cases.
 111                 pass "$test"
 112             }
 113         }
 114     }
 115 }
 116
 117 proc advancei { cmd } {
 118     global gdb_prompt inferior_exited_re
 119
 120     with_test_prefix "$cmd from handleri" {
 121         restart
 122
 123         # Get us into the handler.
 124         gdb_test "break handler"
 125         gdb_test "continue" ".* handler .*" "continue to handler"
 126
 127         set program_exited 0
 128         set test "leave handler"
 129         gdb_test_multiple "$cmd" "${test}" {
 130             -re "Cannot insert breakpoint 0.*${gdb_prompt} $" {
 131                 # Some platforms use a special read-only page for signal
 132                 # trampolines.  We can't set a breakpoint there, and we
 133                 # don't gracefully fall back to single-stepping.
 134                 setup_kfail gdb/8841 "i?86-*-linux*"
 135                 setup_kfail gdb/8841 "*-*-openbsd*"
 136                 fail "$test (could not set breakpoint)"
 137                 return
 138             }
 139             -re "Could not insert single-step breakpoint.*$gdb_prompt $" {
 140                 setup_kfail gdb/8841 "sparc*-*-openbsd*"
 141                 fail "$test (could not insert single-step breakpoint)"
 142             }
 143             -re "Breakpoint \[0-9\]*, handler .*${gdb_prompt} $" {
 144                 fail "$test (hit breakpoint again)"
 145             }
 146             -re "done = 1;.*${gdb_prompt} $" {
 147                 send_gdb "$cmd\n"
 148                 exp_continue -continue_timer
 149             }
 150             -re "\} .. handler .*${gdb_prompt} $" {
 151                 send_gdb "$cmd\n"
 152                 exp_continue -continue_timer
 153             }
 154             -re "signal handler called.*${gdb_prompt} $" {
 155                 pass "$test"
 156             }
 157             -re "main .*${gdb_prompt} $" {
 158                 fail "$test (in main)"
 159             }
 160             -re "$inferior_exited_re normally.*${gdb_prompt} $" {
 161                 fail "$test (program exited)"
 162                 set program_exited 1
 163             }
 164             -re "Make handler return now.*y or n. $" {
 165                 send_gdb "y\n"
 166                 exp_continue -continue_timer
 167             }
 168         }
 169
 170         set test "leave signal trampoline"
 171         gdb_test_multiple "$cmd" "${test}" {
 172             -re "while .*${gdb_prompt} $" {
 173                 pass "$test (in main)"
 174             }
 175             -re "signal handler called.*${gdb_prompt} $" {
 176                 send_gdb "$cmd\n"
 177                 exp_continue -continue_timer
 178             }
 179             -re "return .*${gdb_prompt} $" {
 180                 fail "$test (stepped)"
 181             }
 182             -re "Make .*frame return now.*y or n. $" {
 183                 send_gdb "y\n"
 184                 exp_continue -continue_timer
 185             }
 186             -re "$inferior_exited_re normally.*${gdb_prompt} $" {
 187                 kfail gdb/8744 "$test (program exited)"
 188                 set program_exited 1
 189             }
 190             -re "The program is not being run.*${gdb_prompt} $" {
 191                 if { $program_exited } {
 192                     # Previously kfailed with an exit
 193                     pass "$test (the program is not being run)"
 194                 } else {
 195                     fail "$test (the program is not being run)"
 196                 }
 197             }
 198         }
 199     }
 200 }
 201
 202 # Check that we can step/next our way out of a signal handler.
 203
 204 foreach cmd {"step" "next"} {
 205     advance $cmd
 206 }
 207
 208 foreach cmd {"stepi" "nexti" "finish" "return"} {
 209     advancei $cmd
 210 }
 211
 212 # Check that we can step/next our way into / over a signal handler.
 213
 214 # There are at least the following cases: breakpoint @pc VS breakpoint
 215 # in handler VS step / next / continue.
 216
 217
 218 # Try stepping when there's a signal pending, and a breakpoint at the
 219 # handler.  Should step into the signal handler.
 220
 221 proc skip_to_handler { cmd } {
 222     global infinite_loop
 223
 224     with_test_prefix "$cmd to handler" {
 225         restart
 226         # Use the real-time itimer, as otherwize the process never gets
 227         # enough time to expire the timer.
 228         gdb_test_no_output "set itimer = itimer_real"
 229
 230         # Advance to the infinite loop.
 231         gdb_test "advance $infinite_loop" ".*" "advance to infinite loop"
 232
 233         # Make the signal pending.
 234         sleep 1
 235
 236         # Insert the handler breakpoint.
 237         gdb_test "break handler" ".*" "break handler"
 238
 239         # Step into the handler.
 240         gdb_test "$cmd" " handler .*" "performing $cmd"
 241     }
 242 }
 243
 244 foreach cmd {"step" "next" "continue"} {
 245     skip_to_handler $cmd
 246 }
 247
 248 # Try stepping when there's a signal pending, and a breakpoint at the
 249 # handler's entry-point.  Should step into the signal handler stopping
 250 # at the entry-point.
 251
 252 # Some systems (e.x., GNU/Linux as of 2004-08-30), when delivering a
 253 # signal, resume the process at the first instruction of the signal
 254 # handler and not the first instruction of the signal trampoline.  The
 255 # stack is constructed such that the signal handler still appears to
 256 # have been called by the trampoline code.  This test checks that it
 257 # is possible to stop the inferior, even at that first instruction.
 258
 259 proc skip_to_handler_entry { cmd } {
 260     global infinite_loop
 261
 262     with_test_prefix "$cmd to handler entry" {
 263         restart
 264         # Use the real-time itimer, as otherwize the process never gets
 265         # enough time to expire the timer.
 266         gdb_test_no_output "set itimer = itimer_real"
 267
 268         # Advance to the infinite loop.
 269         gdb_test "advance $infinite_loop" ".*" "advance to infinite loop"
 270
 271         # Make the signal pending.
 272         sleep 1
 273
 274         # Insert / remove the handler breakpoint.
 275         gdb_test "break *handler" ".*" "break handler"
 276         gdb_test "$cmd" " handler .*" "performing $cmd"
 277     }
 278 }
 279
 280 foreach cmd {"stepi" "nexti" "step" "next" "continue"} {
 281     skip_to_handler_entry $cmd
 282 }
 283
 284 # Get the address of where a single-step should land.
 285
 286 proc get_next_pc {test} {
 287     global gdb_prompt
 288     global hex
 289
 290     set next ""
 291     gdb_test_multiple "x/2i \$pc" $test {
 292         -re "$hex .*:\[^\r\n\]+\r\n\[ \]+($hex).*\.\r\n$gdb_prompt $" {
 293             set next $expect_out(1,string)
 294             pass $test
 295         }
 296     }
 297
 298     return $next
 299 }
 300
 301 # Test that the command skipped over the handler.
 302
 303 proc test_skip_handler {cmd} {
 304     if {$cmd == "stepi" || $cmd == "nexti"} {
 305         set next_pc [get_next_pc "get next PC"]
 306         gdb_test "$cmd" "dummy = 0.*" "performing $cmd"
 307         gdb_test "p /x \$pc" " = $next_pc" "advanced"
 308     } else {
 309         gdb_test "$cmd" "done = 0.*" "performing $cmd"
 310     }
 311 }
 312
 313 # Try stepping when there's a signal pending but no breakpoints.
 314 # Should skip the handler advancing to the next line.
 315
 316 proc skip_over_handler { cmd } {
 317     global infinite_loop
 318     global clear_done
 319
 320     with_test_prefix "$cmd over handler" {
 321         restart
 322         # Use the real-time itimer, as otherwize the process never gets
 323         # enough time to expire the timer.
 324         gdb_test_no_output "set itimer = itimer_real"
 325
 326         gdb_test "break $clear_done" ".*" "break clear done"
 327
 328         # Advance to the infinite loop.
 329         gdb_test "advance $infinite_loop" ".*" "advance to infinite loop"
 330
 331         # Make the signal pending.
 332         sleep 1
 333
 334         test_skip_handler $cmd
 335     }
 336 }
 337
 338 foreach cmd {"stepi" "nexti" "step" "next" "continue"} {
 339     skip_over_handler $cmd
 340 }
 341
 342 # Try stepping when there's a signal pending, a pre-existing
 343 # breakpoint at the current instruction, and a breakpoint in the
 344 # handler.  Should advance to the signal handler.
 345
 346 proc breakpoint_to_handler { cmd } {
 347     global infinite_loop
 348
 349     with_test_prefix "$cmd on breakpoint, to handler" {
 350         restart
 351         # Use the real-time itimer, as otherwize the process never gets
 352         # enough time to expire the timer.
 353         gdb_test_no_output "set itimer = itimer_real"
 354
 355         gdb_test "break $infinite_loop" ".*" "break infinite loop"
 356         gdb_test "break handler" ".*" "break handler"
 357
 358         # Continue to the infinite loop.
 359         gdb_test "continue" "while ..done.*" "continue to infinite loop"
 360
 361         # Make the signal pending.
 362         sleep 1
 363
 364         gdb_test "$cmd" " handler .*" "performing $cmd"
 365     }
 366 }
 367
 368 foreach cmd {"step" "next" "continue"} {
 369     breakpoint_to_handler $cmd
 370 }
 371
 372 # Try stepping when there's a signal pending, and a breakpoint at the
 373 # handler's entry instruction and a breakpoint at the current
 374 # instruction.  Should step into the signal handler and breakpoint at
 375 # that entry instruction.
 376
 377 # Some systems (e.x., GNU/Linux as of 2004-08-30), when delivering a
 378 # signal, resume the process at the first instruction of the signal
 379 # handler and not the first instruction of the signal trampoline.  The
 380 # stack is constructed such that the signal handler still appears to
 381 # have been called by the trampoline code.  This test checks that it
 382 # is possible to stop the inferior, even at that first instruction.
 383
 384 proc breakpoint_to_handler_entry { cmd } {
 385     global infinite_loop
 386
 387     with_test_prefix "$cmd on breakpoint, to handler entry" {
 388         restart
 389         # Use the real-time itimer, as otherwize the process never gets
 390         # enough time to expire the timer.
 391         gdb_test_no_output "set itimer = itimer_real"
 392
 393         gdb_test "break $infinite_loop" ".*" "break infinite loop"
 394         gdb_test "break *handler" ".*" "break handler"
 395
 396         # Continue to the infinite loop.
 397         gdb_test "continue" "while ..done.*" "continue to infinite loop"
 398
 399         # Make the signal pending.
 400         sleep 1
 401
 402         gdb_test "$cmd" " handler .*" "performing $cmd"
 403     }
 404 }
 405
 406 foreach cmd {"step" "next" "continue"} {
 407     breakpoint_to_handler_entry $cmd
 408 }
 409
 410 # Try stepping when there's a signal pending, and a pre-existing
 411 # breakpoint at the current instruction, and no breakpoint in the
 412 # handler.  Should advance to the next line/instruction.
 413
 414 proc breakpoint_over_handler { cmd } {
 415     global infinite_loop
 416     global clear_done
 417
 418     with_test_prefix "$cmd on breakpoint, skip handler" {
 419         restart
 420         # Use the real-time itimer, as otherwize the process never gets
 421         # enough time to expire the timer.
 422         gdb_test_no_output "set itimer = itimer_real"
 423
 424         gdb_test "break $infinite_loop" ".*" "break infinite loop"
 425
 426         gdb_test "break $clear_done" ".*" "break clear done"
 427
 428         # Continue to the infinite loop
 429         gdb_test "continue" "while ..done.*" "continue to infinite loop"
 430
 431         # Make the signal pending
 432         sleep 1
 433
 434         test_skip_handler $cmd
 435     }
 436 }
 437
 438 foreach cmd {"stepi" "nexti" "step" "next" "continue"} {
 439     breakpoint_over_handler $cmd
 440 }