Re: Pending breakpoints in MI

[Vladimir Prus <ghost at cs dot msu dot su>]

Joel Brobecker wrote:

> Volodya,
> 
> You forgot to provide a ChangeLog...

Oops, sorry. Attached now -- there are three ChangeLog
files affected, and I provide bits for each.

>>  gdb_breakpoint (char *address, char *condition,
>>  int hardwareflag, int tempflag,
>>  int thread, int ignore_count,
>> +                int pending,
>>  char **error_message)
> 
> I can't believe I'm saying this, since I absolutely hate tabs, but
> these are the coding rules: You need to use a tab instead of 8 spaces
> in the line above. Compare for instance how the "char **error_message"
> line is indented.

It appears I've failed to re-configure Emacs properly after 
rearranging my local environment. I've fixed all instances now
(and one function which got space indenting in the previous patch).

>> --- gdb/testsuite/gdb.mi/mi-pending.exp
>> (/patches/pending_mi_2_code_duplication)     (revision 45)
>> +++ gdb/testsuite/gdb.mi/mi-pending.exp
>> (/patches/pending_mi_3_breakpoints)  (revision 45) @@ -0,0 +1,75 @@
>> +# Copyright 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
> 
> Shouldn't the copyright year be only 2007?

Yes, right.

>> --- gdb/mi/mi-cmd-break.c    (/patches/pending_mi_2_code_duplication)
>> (revision 45)
>> +++ gdb/mi/mi-cmd-break.c    (/patches/pending_mi_3_breakpoints)     (revision
>> 45) @@ -63,7 +63,10 @@ enum bp_type
>>     breakpoint.  -break-insert -t -h <location> --> insert a temporary
>>     hw bp.
>>     -break-insert -r <regexp> --> insert a bp at functions matching
>> -   <regexp> */
>> +   <regexp>
>> +
>> +   The -f flag makes GDB create a pending breakpoint if no
>> +   locations for breakpoint are found now.  */
> 
> Actually, I think that the entire comment needs to be rewritten
> in a way that the syntax is not described there at all. Just say
> that this function implements the -break-insert command which, as
> its name suggests, inserts a breakpoint.  The syntax needs to be
> documented in the GDB manual. See
> http://www.sourceware.org/gdb/current/onlinedocs/gdb_25.html#SEC259
> for what is currently documented. Let's use this opportunity to
> make sure that every option (and only the supported options) are
> documented.

I've done so. Eli, does the manual changes in the attached patch look
good to you?

Thanks a lot for the review!
Revised patch attached, is it OK?

- Volodya

        gdb/
        Add support for pending breakpoints in MI.
        * gdb.h (gdb_breakpoint): Add parameter pending.
        * breakpoint.c (break_command_1): Fix formatting.
        (gdb_breakpoint): Add parameter pending.  Fix 
        formatting.
        * mi/mi-cmd-break.c (mi_break_insert): Change
        comment to refer to manual.  Add support for
        the -f flag, for pending breakpoint.
                
        gdb/doc
        * gdb.texinfo (GDB/MI Breakpoint Commands): Document
        the -f option for -break-insert, remove -r option,
        and clarify specification of location.

        gdb/testsuite
        * gdb.mi/mi-pending.exp: New.
        * gdb.mi/mi-pending.c: New.
        * gdb.mi/mi-pendshr.c: New.

--- gdb/doc/gdb.texinfo	(/patches/pending_mi_2_code_duplication)	(revision 49)
+++ gdb/doc/gdb.texinfo	(/patches/pending_mi_3_breakpoints)	(revision 49)
@@ -18055,13 +18055,13 @@ N.A.
 @subsubheading Synopsis
 
 @smallexample
- -break-insert [ -t ] [ -h ] [ -r ]
+ -break-insert [ -t ] [ -h ] [ -f ]
     [ -c @var{condition} ] [ -i @var{ignore-count} ]
-    [ -p @var{thread} ] [ @var{line} | @var{addr} ]
+    [ -p @var{thread} ] [ @var{location} ]
 @end smallexample
 
 @noindent
-If specified, @var{line}, can be one of:
+If specified, @var{location}, can be one of:
 
 @itemize @bullet
 @item function
@@ -18084,10 +18084,12 @@ Insert a hardware breakpoint.
 Make the breakpoint conditional on @var{condition}.
 @item -i @var{ignore-count}
 Initialize the @var{ignore-count}.
-@item -r
-Insert a regular breakpoint in all the functions whose names match the
-given regular expression.  Other flags are not applicable to regular
-expressions.
+@item -f
+If @var{location} cannot be parsed (for example if it
+refers to unknown files or functions), create a pending
+breakpoint. Without this flag, @value{GDBN} will report
+an error, and won't create a breakpoint, if @var{location}
+cannot be parsed.
 @end table
 
 @subsubheading Result
--- gdb/breakpoint.c	(/patches/pending_mi_2_code_duplication)	(revision 49)
+++ gdb/breakpoint.c	(/patches/pending_mi_3_breakpoints)	(revision 49)
@@ -5638,9 +5638,9 @@ break_command_1 (char *arg, int flag, in
   int tempflag = flag & BP_TEMPFLAG;
 
   return break_command_really (arg, 
-                               NULL, 0, 1 /* parse arg */,
-                               tempflag, hardwareflag,
-                               pending_break_support, from_tty);
+			       NULL, 0, 1 /* parse arg */,
+			       tempflag, hardwareflag,
+			       pending_break_support, from_tty);
 }
 
 
@@ -5648,13 +5648,15 @@ enum gdb_rc
 gdb_breakpoint (char *address, char *condition,
 		int hardwareflag, int tempflag,
 		int thread, int ignore_count,
+		int pending,
 		char **error_message)
 {
-    return break_command_really (address, condition, thread,
-                                 0 /* condition and thread are valid.  */,
-                                 tempflag, hardwareflag,
-                                 AUTO_BOOLEAN_FALSE /* no pending. */,
-                                 0);
+  return break_command_really (address, condition, thread,
+			       0 /* condition and thread are valid.  */,
+			       tempflag, hardwareflag,
+			       pending 
+			       ? AUTO_BOOLEAN_TRUE : AUTO_BOOLEAN_FALSE,
+			       0);
 }
 
 
--- gdb/gdb.h	(/patches/pending_mi_2_code_duplication)	(revision 49)
+++ gdb/gdb.h	(/patches/pending_mi_3_breakpoints)	(revision 49)
@@ -51,6 +51,7 @@ enum gdb_rc gdb_breakpoint_query (struct
 enum gdb_rc gdb_breakpoint (char *address, char *condition,
 			    int hardwareflag, int tempflag,
 			    int thread, int ignore_count,
+			    int pending,
 			    char **error_message);
 
 /* Switch thread and print notification. */
--- gdb/testsuite/gdb.mi/mi-pending.exp	(/patches/pending_mi_2_code_duplication)	(revision 49)
+++ gdb/testsuite/gdb.mi/mi-pending.exp	(/patches/pending_mi_3_breakpoints)	(revision 49)
@@ -0,0 +1,75 @@
+# Copyright 2007 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 mi-support.exp
+set MIFLAGS "-i=mi"
+
+if $tracelevel then {
+    strace $tracelevel
+}
+
+#
+# test running programs
+#
+set prms_id 0
+set bug_id 0
+
+if {[skip_shlib_tests]} {
+    return 0
+}
+
+set testfile "mi-pending"
+set libfile "mi-pendshr"
+set srcfile $testfile.c
+set libsrc  $srcdir/$subdir/$libfile.c
+set binfile $objdir/$subdir/$testfile
+set lib_sl  $objdir/$subdir/$libfile.sl
+
+set lib_opts  debug
+set exec_opts [list debug shlib=$lib_sl]
+
+if [get_compiler_info ${binfile}] {
+    return -1
+}
+
+if { [gdb_compile_shlib $libsrc $lib_sl $lib_opts] != ""
+     || [gdb_compile $srcdir/$subdir/$srcfile $binfile executable $exec_opts] != ""} {
+    untested "Could not compile either $libsrc or $srcdir/$subdir/$srcfile."
+    return -1
+}
+
+# Start with a fresh gdb.
+
+gdb_exit
+mi_gdb_start
+mi_gdb_reinitialize_dir $srcdir/$subdir
+mi_gdb_load ${binfile}
+gdb_load_shlibs $lib_sl
+
+if [target_info exists gdb_stub] {
+    gdb_step_for_stub;
+}
+
+# Set pending breakpoint via MI
+mi_gdb_test "-break-insert -f pendfunc1" \
+    ".*\\^done,bkpt=\{number=\"1\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\\(p\\)\",addr=\"<PENDING>\",pending=\"pendfunc1\",times=\"0\"\}"\
+    "MI pending breakpoint on pendfunc1"
+
+mi_run_cmd
+
+# Make sure we hit breakpoint.
+mi_gdb_test "" \
+    ".*\\*stopped,reason=\"breakpoint-hit\",bkptno=\"1\".*func=\"pendfunc1\".*" \
+    "Run till MI pending breakpoint on pendfunc1"
\ No newline at end of file
--- gdb/testsuite/gdb.mi/mi-pending.c	(/patches/pending_mi_2_code_duplication)	(revision 49)
+++ gdb/testsuite/gdb.mi/mi-pending.c	(/patches/pending_mi_3_breakpoints)	(revision 49)
@@ -0,0 +1,34 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2007 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/>.
+
+   Please email any bugs, comments, and/or additions to this file to:
+   bug-gdb@prep.ai.mit.edu  */
+
+#include <stdio.h>
+
+int k = 0;
+
+extern void pendfunc (int x);
+
+int main()
+{
+  pendfunc (3); /* break main here */
+  pendfunc (4);
+  k = 1;
+  pendfunc (3);
+  return 0;
+}
--- gdb/testsuite/gdb.mi/mi-pendshr.c	(/patches/pending_mi_2_code_duplication)	(revision 49)
+++ gdb/testsuite/gdb.mi/mi-pendshr.c	(/patches/pending_mi_3_breakpoints)	(revision 49)
@@ -0,0 +1,32 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2007 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/>.
+
+   Please email any bugs, comments, and/or additions to this file to:
+   bug-gdb@prep.ai.mit.edu  */
+
+#include <stdio.h>
+
+void pendfunc1 (int x)
+{
+  int y = x + 4;
+  printf ("in pendfunc1, x is %d\n", x);
+}
+
+void pendfunc (int x)
+{
+  pendfunc1 (x);
+}
--- gdb/mi/mi-cmd-break.c	(/patches/pending_mi_2_code_duplication)	(revision 49)
+++ gdb/mi/mi-cmd-break.c	(/patches/pending_mi_3_breakpoints)	(revision 49)
@@ -56,14 +56,8 @@ enum bp_type
     REGEXP_BP
   };
 
-/* Insert a breakpoint. The type of breakpoint is specified by the
-   first argument: -break-insert <location> --> insert a regular
-   breakpoint.  -break-insert -t <location> --> insert a temporary
-   breakpoint.  -break-insert -h <location> --> insert an hardware
-   breakpoint.  -break-insert -t -h <location> --> insert a temporary
-   hw bp.  
-   -break-insert -r <regexp> --> insert a bp at functions matching
-   <regexp> */
+/* Implements the -break-insert command.
+   See the MI manual for the list of possible options.  */
 
 enum mi_cmd_result
 mi_cmd_break_insert (char *command, char **argv, int argc)
@@ -74,12 +68,13 @@ mi_cmd_break_insert (char *command, char
   int thread = -1;
   int ignore_count = 0;
   char *condition = NULL;
+  int pending = 0;
   enum gdb_rc rc;
   struct gdb_events *old_hooks;
   enum opt
     {
       HARDWARE_OPT, TEMP_OPT /*, REGEXP_OPT */ , CONDITION_OPT,
-      IGNORE_COUNT_OPT, THREAD_OPT
+      IGNORE_COUNT_OPT, THREAD_OPT, PENDING_OPT
     };
   static struct mi_opt opts[] =
   {
@@ -88,6 +83,7 @@ mi_cmd_break_insert (char *command, char
     {"c", CONDITION_OPT, 1},
     {"i", IGNORE_COUNT_OPT, 1},
     {"p", THREAD_OPT, 1},
+    {"f", PENDING_OPT, 0},
     { 0, 0, 0 }
   };
 
@@ -122,6 +118,9 @@ mi_cmd_break_insert (char *command, char
 	case THREAD_OPT:
 	  thread = atol (optarg);
 	  break;
+	case PENDING_OPT:
+	  pending = 1;
+	  break;
 	}
     }
 
@@ -139,12 +138,14 @@ mi_cmd_break_insert (char *command, char
       rc = gdb_breakpoint (address, condition,
 			   0 /*hardwareflag */ , temp_p,
 			   thread, ignore_count,
+			   pending,
 			   &mi_error_message);
       break;
     case HW_BP:
       rc = gdb_breakpoint (address, condition,
 			   1 /*hardwareflag */ , temp_p,
 			   thread, ignore_count,
+			   pending,
 			   &mi_error_message);
       break;
 #if 0