[4/4] (Ada) Add gdb-mi support for stopping at start of exception handler.

  Following my previous commit which add support for stopping at start of
exception handler, this commit adds required gdb-mi support for this
feature.

gdb/ChangeLog:

    * mi/mi-cmd-catch.c (mi_cmd_catch_handlers): New function.
    * mi/mi-cmds.c (struct mi_cmds): Add catch-handlers command.
    * mi/mi-cmds.h (mi_cmd_catch_handlers): Add external declaration.
    * NEWS: Document "-catch-handlers" command.

gdb/doc/ChangeLog:

    * gdb.texinfo (Ada Exception gdb/mi Catchpoints): Add
    documentation for new "-catch-handlers" command.

gdb/testsuite/ChangeLog:

    * gdb.ada/mi_catch_ex_hand.exp: New testcase.
    * gdb.ada/mi_catch_ex_hand/foo.adb: New file.

Tested on x86_64-linux.
---
 gdb/NEWS                                       |   4 +
 gdb/doc/gdb.texinfo                            |  44 ++++++++
 gdb/mi/mi-cmd-catch.c                          |  73 ++++++++++++-
 gdb/mi/mi-cmds.c                               |   2 +
 gdb/mi/mi-cmds.h                               |   1 +
 gdb/testsuite/gdb.ada/mi_catch_ex_hand.exp     | 137 +++++++++++++++++++++++++
 gdb/testsuite/gdb.ada/mi_catch_ex_hand/foo.adb |  33 ++++++
 7 files changed, 292 insertions(+), 2 deletions(-)
 create mode 100644 gdb/testsuite/gdb.ada/mi_catch_ex_hand.exp
 create mode 100644 gdb/testsuite/gdb.ada/mi_catch_ex_hand/foo.adb
  

> From: Xavier Roirand <roirand@adacore.com>
> Cc: Xavier Roirand <roirand@adacore.com>,	brobecker@adacore.com
> Date: Mon, 29 Jan 2018 13:47:06 +0100
> 
> Following my previous commit which add support for stopping at start of
> exception handler, this commit adds required gdb-mi support for this
> feature.
> 
> gdb/ChangeLog:
> 
>     * mi/mi-cmd-catch.c (mi_cmd_catch_handlers): New function.
>     * mi/mi-cmds.c (struct mi_cmds): Add catch-handlers command.
>     * mi/mi-cmds.h (mi_cmd_catch_handlers): Add external declaration.
>     * NEWS: Document "-catch-handlers" command.
> 
> gdb/doc/ChangeLog:
> 
>     * gdb.texinfo (Ada Exception gdb/mi Catchpoints): Add
>     documentation for new "-catch-handlers" command.
> 
> gdb/testsuite/ChangeLog:
> 
>     * gdb.ada/mi_catch_ex_hand.exp: New testcase.
>     * gdb.ada/mi_catch_ex_hand/foo.adb: New file.

OK for the documentation parts.

Thanks.
  

Hi Xavier,

On Mon, Jan 29, 2018 at 01:47:06PM +0100, Xavier Roirand wrote:
> Following my previous commit which add support for stopping at start of
> exception handler, this commit adds required gdb-mi support for this
> feature.
> 
> gdb/ChangeLog:
> 
>     * mi/mi-cmd-catch.c (mi_cmd_catch_handlers): New function.
>     * mi/mi-cmds.c (struct mi_cmds): Add catch-handlers command.

"struct mi_cmds" -> "mi_cmds".

Rationale: You changed the variable called "mi_cmds", not "struct
mi_cmds". If you had changed the definition of the struct (ie,
the definition of the type), then you would have said "struct mi_cmd"
(note the lack of 's' as the variable and the type have a slightly
different name in this case).

>     * mi/mi-cmds.h (mi_cmd_catch_handlers): Add external declaration.
>     * NEWS: Document "-catch-handlers" command.
> 
> gdb/doc/ChangeLog:
> 
>     * gdb.texinfo (Ada Exception gdb/mi Catchpoints): Add
>     documentation for new "-catch-handlers" command.
> 
> gdb/testsuite/ChangeLog:
> 
>     * gdb.ada/mi_catch_ex_hand.exp: New testcase.
>     * gdb.ada/mi_catch_ex_hand/foo.adb: New file.
> 
> Tested on x86_64-linux.

Only a few minor nits. See below.

> ---
>  gdb/NEWS                                       |   4 +
>  gdb/doc/gdb.texinfo                            |  44 ++++++++
>  gdb/mi/mi-cmd-catch.c                          |  73 ++++++++++++-
>  gdb/mi/mi-cmds.c                               |   2 +
>  gdb/mi/mi-cmds.h                               |   1 +
>  gdb/testsuite/gdb.ada/mi_catch_ex_hand.exp     | 137 +++++++++++++++++++++++++
>  gdb/testsuite/gdb.ada/mi_catch_ex_hand/foo.adb |  33 ++++++
>  7 files changed, 292 insertions(+), 2 deletions(-)
>  create mode 100644 gdb/testsuite/gdb.ada/mi_catch_ex_hand.exp
>  create mode 100644 gdb/testsuite/gdb.ada/mi_catch_ex_hand/foo.adb
> 
> diff --git a/gdb/NEWS b/gdb/NEWS
> index f69173a..9cd38f3 100644
> --- a/gdb/NEWS
> +++ b/gdb/NEWS
> @@ -377,6 +377,10 @@ show disassembler-options
>    List the shared libraries in the program.  This is
>    equivalent to the CLI command "info shared".
>  
> +-catch-handlers
> +  Catchpoints stopping the program when Ada exceptions are
> +  handled.  This is equivalent to the CLI command "catch handlers".
> +
>  *** Changes in GDB 7.12
>  
>  * GDB and GDBserver now build with a C++ compiler by default.
> diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
> index 9ddfba5..4ed5f6b 100644
> --- a/gdb/doc/gdb.texinfo
> +++ b/gdb/doc/gdb.texinfo
> @@ -28537,6 +28537,50 @@ times="0",original-location="__gnat_debug_raise_exception"@}
>  (gdb)
>  @end smallexample
>  
> +@subheading The @code{-catch-handlers} Command
> +@findex -catch-handlers
> +
> +@subsubheading Synopsis
> +
> +@smallexample
> + -catch-handlers [ -c @var{condition}] [ -d ] [ -e @var{exception-name} ]
> +    [ -t ]
> +@end smallexample
> +
> +Add a catchpoint stopping when Ada exceptions are handled.
> +By default, the command stops the program when any Ada exception
> +gets handled.  But it is also possible, by using some of the
> +optional parameters described below, to create more selective
> +catchpoints.
> +
> +The possible optional parameters for this command are:
> +
> +@table @samp
> +@item -c @var{condition}
> +Make the catchpoint conditional on @var{condition}.
> +@item -d
> +Create a disabled catchpoint.
> +@item -e @var{exception-name}
> +Only stop when @var{exception-name} is handled.
> +@item -t
> +Create a temporary catchpoint.
> +@end table
> +
> +@subsubheading @value{GDBN} Command
> +
> +The corresponding @value{GDBN} command is @samp{catch handlers}.
> +
> +@subsubheading Example
> +
> +@smallexample
> +-catch-handlers -e Constraint_Error
> +^done,bkptno="4",bkpt=@{number="4",type="breakpoint",disp="keep",
> +enabled="y",addr="0x0000000000402f68",
> +what="`Constraint_Error' Ada exception handlers",thread-groups=["i1"],
> +times="0",original-location="__gnat_begin_handler"@}
> +(gdb)
> +@end smallexample
> +
>  @c %%%%%%%%%%%%%%%%%%%%%%%%%%%% SECTION %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
>  @node GDB/MI Program Context
>  @section @sc{gdb/mi}  Program Context
> diff --git a/gdb/mi/mi-cmd-catch.c b/gdb/mi/mi-cmd-catch.c
> index a0f311a..f124f56 100644
> --- a/gdb/mi/mi-cmd-catch.c
> +++ b/gdb/mi/mi-cmd-catch.c
> @@ -157,8 +157,77 @@ mi_cmd_catch_exception (const char *cmd, char *argv[], int argc)
>    if (exception_name != NULL)
>      exception_name = xstrdup (exception_name);
>    create_ada_exception_catchpoint (gdbarch, ex_kind,
> -				   exception_name, condition,
> -				   temp, enabled, 0);
> +				   exception_name,
> +				   condition, temp, enabled, 0);
> +}
> +
> +/* Handler for the -catch-handlers command.  */
> +
> +void
> +mi_cmd_catch_handlers (const char *cmd, char *argv[], int argc)
> +{
> +  struct gdbarch *gdbarch = get_current_arch ();
> +  std::string condition;
> +  int enabled = 1;
> +  char *exception_name = NULL;
> +  int temp = 0;
> +  enum ada_exception_catchpoint_kind ex_kind = ada_catch_handlers;

This is not a variable, so why not use ada_catch_handlers
directly?

> +  int oind = 0;
> +  char *oarg;
> +
> +  enum opt
> +    {
> +      OPT_CONDITION, OPT_DISABLED, OPT_EXCEPTION_NAME, OPT_TEMP
> +    };
> +  static const struct mi_opt opts[] =
> +    {
> +      { "c", OPT_CONDITION, 1},
> +      { "d", OPT_DISABLED, 0 },
> +      { "e", OPT_EXCEPTION_NAME, 1 },
> +      { "t", OPT_TEMP, 0 },
> +      { 0, 0, 0 }
> +    };
> +
> +  for (;;)
> +    {
> +      int opt = mi_getopt ("-catch-handlers", argc, argv, opts,
> +			   &oind, &oarg);
> +
> +      if (opt < 0)
> +        break;
> +
> +      switch ((enum opt) opt)
> +        {
> +	case OPT_CONDITION:
> +	  condition.assign (oarg);
> +	  break;
> +	case OPT_DISABLED:
> +	  enabled = 0;
> +	  break;
> +	case OPT_EXCEPTION_NAME:
> +	  exception_name = oarg;
> +	  break;
> +	case OPT_TEMP:
> +	  temp = 1;
> +	  break;
> +        }
> +    }
> +
> +  /* This command does not accept any argument.  Make sure the user
> +     did not provide any.  */
> +  if (oind != argc)
> +    error (_("Invalid argument: %s"), argv[oind]);
> +
> +  scoped_restore restore_breakpoint_reporting
> +    = setup_breakpoint_reporting ();
> +  /* create_ada_exception_catchpoint needs EXCEPTION_NAME to be
> +     xstrdup'ed, and will assume control of its lifetime.  */
> +  if (exception_name != NULL)
> +    exception_name = xstrdup (exception_name);
> +  create_ada_exception_catchpoint (gdbarch, ex_kind,
> +				   exception_name,
> +				   condition, temp, enabled, 0);
>  }
>  
>  /* Common path for the -catch-load and -catch-unload.  */
> diff --git a/gdb/mi/mi-cmds.c b/gdb/mi/mi-cmds.c
> index c9ffda1..51014ed 100644
> --- a/gdb/mi/mi-cmds.c
> +++ b/gdb/mi/mi-cmds.c
> @@ -69,6 +69,8 @@ static struct mi_cmd mi_cmds[] =
>                     &mi_suppress_notification.breakpoint),
>    DEF_MI_CMD_MI_1 ("catch-exception", mi_cmd_catch_exception,
>                     &mi_suppress_notification.breakpoint),
> +  DEF_MI_CMD_MI_1 ("catch-handlers", mi_cmd_catch_handlers,
> +                   &mi_suppress_notification.breakpoint),
>    DEF_MI_CMD_MI_1 ("catch-load", mi_cmd_catch_load,
>                     &mi_suppress_notification.breakpoint),
>    DEF_MI_CMD_MI_1 ("catch-unload", mi_cmd_catch_unload,
> diff --git a/gdb/mi/mi-cmds.h b/gdb/mi/mi-cmds.h
> index c27f3ba..af96585 100644
> --- a/gdb/mi/mi-cmds.h
> +++ b/gdb/mi/mi-cmds.h
> @@ -41,6 +41,7 @@ extern mi_cmd_argv_ftype mi_cmd_break_passcount;
>  extern mi_cmd_argv_ftype mi_cmd_break_watch;
>  extern mi_cmd_argv_ftype mi_cmd_catch_assert;
>  extern mi_cmd_argv_ftype mi_cmd_catch_exception;
> +extern mi_cmd_argv_ftype mi_cmd_catch_handlers;
>  extern mi_cmd_argv_ftype mi_cmd_catch_load;
>  extern mi_cmd_argv_ftype mi_cmd_catch_unload;
>  extern mi_cmd_argv_ftype mi_cmd_disassemble;
> diff --git a/gdb/testsuite/gdb.ada/mi_catch_ex_hand.exp b/gdb/testsuite/gdb.ada/mi_catch_ex_hand.exp
> new file mode 100644
> index 0000000..0137add
> --- /dev/null
> +++ b/gdb/testsuite/gdb.ada/mi_catch_ex_hand.exp
> @@ -0,0 +1,137 @@
> +# Copyright 2011-2018 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 3 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, see <http://www.gnu.org/licenses/>.
> +
> +load_lib "ada.exp"
> +
> +standard_ada_testfile foo
> +
> +if {[gdb_compile_ada "${srcfile}" "${binfile}" executable [list debug additional_flags=-gnata ]] != "" } {
> +  return -1
> +}
> +
> +# A global variable used to simplify the maintenance of some of
> +# the regular expressions below.
> +set eol "\[\r\n\]+"
> +
> +# Before going any further, verify that we can insert exception
> +# handlers catchpoints...  That way, we won't have to do this while
> +# doing the actual GDB/MI testing.
> +
> +clean_restart ${testfile}
> +
> +if ![runto_main] then {
> +   fail "cannot run to main, testcase aborted"
> +   return 0
> +}
> +
> +set msg "insert catchpoint on all Ada exceptions handlers"
> +gdb_test_multiple "catch handlers" $msg {
> +    -re "Catchpoint $decimal: all Ada exceptions handlers$eol$gdb_prompt $" {
> +	pass $msg
> +    }
> +    -re "Your Ada runtime appears to be missing some debugging information.*\[\r\n\]+$gdb_prompt $" {
> +	# If the runtime was not built with enough debug information,
> +	# or if it was stripped, we can not test exception
> +	# catchpoints.
> +	unsupported $msg
> +	return -1
> +    }
> +}
> +
> +# Now, we can start the GDB/MI testing itself...
> +
> +load_lib mi-support.exp
> +set MIFLAGS "-i=mi"
> +
> +gdb_exit
> +if [mi_gdb_start] {
> +    continue
> +}
> +
> +#############################################
> +# 1. Try catching all exceptions handlers.  #
> +#############################################
> +
> +if ![mi_run_to_main] then {
> +   fail "cannot run to main, testcase aborted"
> +   return 0
> +}
> +
> +mi_gdb_test "-catch-handlers" \
> +            "\\^done,bkptno=\"$decimal\",bkpt={.*disp=\"keep\",enabled=\"y\",addr=\"$hex\",what=\"all Ada exceptions handlers\",.*}" \
> +            "catch all exceptions handlers"
> +
> +# Continue to exception handler.
> +
> +proc continue_to_exception_handler { test line } {
> +
> +    global decimal
> +
> +    mi_send_resuming_command "exec-continue" "$test"
> +
> +    # Now MI stream output.
> +    mi_expect_stop \
> +	"breakpoint-hit\",disp=\"keep\",bkptno=\"$decimal\",exception-name=\"exception\"?" \
> +	"foo" "" ".*" "$line" \
> +	".*" \
> +        $test
> +}
> +
> +# We don't have the exception name info when stopping at the exception handlers
> +# breakpoint so we use source line to check if the inferior stops at the

breakpoint -> catchpoint.

No other comments past this point.

> +# right location.
> +
> +set bp_ce_location [gdb_get_line_number "BREAK1" ${testdir}/foo.adb]
> +continue_to_exception_handler \
> +    "continue until CE handling caught by all-exceptions handlers catchpoint" \
> +    "$bp_ce_location"
> +
> +set bp_pe_location [gdb_get_line_number "BREAK2" ${testdir}/foo.adb]
> +continue_to_exception_handler \
> +    "continue until PE handling caught by all-exceptions handlers catchpoint" \
> +    "$bp_pe_location"
> +
> +##########################################################
> +# 2. Try catching only some of the exceptions handlers.  #
> +##########################################################
> +
> +# Here is the scenario:
> +#  - Restart the debugger from scratch, runto_main
> +#  - We'll catch only "Constraint_Error handlers"
> +#  - continue, we should stop at the Constraint_Error exception handler
> +#  - continue, we should not stop at the Program_Error exception handler
> +#    but exit instead.
> +
> +if ![mi_run_to_main] then {
> +   fail "cannot run to main, testcase aborted"
> +   return 0
> +}
> +
> +mi_gdb_test "-catch-handlers -e Constraint_Error" \
> +            "\\^done,bkptno=\"$decimal\",bkpt={.*disp=\"keep\",enabled=\"y\",addr=\"$hex\",what=\"`Constraint_Error' Ada exception handlers\",.*}" \
> +            "catch Constraint_Error"
> +
> +mi_execute_to "exec-continue" \
> +              "breakpoint-hit\",disp=\"keep\",bkptno=\"$decimal\",exception-name=\"exception\"?" \
> +              "foo" "" ".*" "$bp_ce_location" \
> +              ".*" \
> +              "continue to exception catchpoint hit"
> +
> +# Exit the inferior.
> +mi_send_resuming_command "exec-continue" "continuing to inferior exit"
> +mi_expect_stop "exited-normally" "" "" "" "" "" "exit normally"
> +
> +mi_gdb_exit
> +return 0
> diff --git a/gdb/testsuite/gdb.ada/mi_catch_ex_hand/foo.adb b/gdb/testsuite/gdb.ada/mi_catch_ex_hand/foo.adb
> new file mode 100644
> index 0000000..da701a3
> --- /dev/null
> +++ b/gdb/testsuite/gdb.ada/mi_catch_ex_hand/foo.adb
> @@ -0,0 +1,33 @@
> +--  Copyright 2007-2018 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 3 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, see <http://www.gnu.org/licenses/>.
> +
> +procedure Foo is
> +begin
> +
> +   begin
> +      raise Constraint_Error;
> +   exception
> +      when Constraint_Error => -- BREAK1
> +         null;
> +   end;
> +
> +   begin
> +      raise Program_Error;
> +   exception
> +      when Program_Error => -- BREAK2
> +         null;
> +   end;
> +
> +end Foo;
> -- 
> 2.7.4