[patch 2/2] [+doc] New -iex and -ix: -ex and -x before inferior load

[Jan Kratochvil <jan dot kratochvil at redhat dot com>]

Hi,

I also wanted to write this patch for years and for auto-load patch being
prepared it gets handy a lot.

# mv /usr/lib/debug /usr/lib/debug-x

# oops
$ ./gdb -q /usr/bin/gdb gdb.core
Reading symbols from /usr/bin/gdb...(no debugging symbols found)...done.

# naively - not working
$ ./gdb -q -ex 'set debug-file-directory /usr/lib/debug-x' /usr/bin/gdb gdb.core
Reading symbols from /usr/bin/gdb...(no debugging symbols found)...done.

# old way
$ ./gdb -q -ex 'set debug-file-directory /usr/lib/debug-x' -ex 'file /usr/bin/gdb' -ex 'core-file gdb.core'
Reading symbols from /usr/bin/gdb...Reading symbols from /usr/lib/debug-x/usr/bin/gdb.debug...done.done.

->
# new way
$ ./gdb -q -iex 'set debug-file-directory /usr/lib/debug-x' /usr/bin/gdb gdb.core
Reading symbols from /usr/bin/gdb...Reading symbols from /usr/lib/debug-x/usr/bin/gdb.debug...done.done.

I have always difficult time explaining people how to adjust the commandline
to apply 'set debug-file-directory', morevoer if you also load a core file or
attach to an executable.

Another use case is to apply 'set complaints' for the inferior loading.

No regressions on {x86_64,x86_64-m32,i686}-fedora17-linux-gnu.


Thanks,
Jan


gdb/
2012-02-25  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* NEWS: Describe new options --init-command=FILE, -ix and
	--init-eval-command=COMMAND, -iex.
	* main.c (struct cmdarg): New enum items CMDARG_INIT_FILE and
	CMDARG_INIT_COMMAND.
	(captured_main): New enum items OPT_IX and OPT_IEX.  Add
	"init-command", "init-eval-command", "ix" and "iex" to the variable
	long_options.  Handle OPT_IX and OPT_IEX.  Process them from CMDARG_VEC.
	New comment for CMDARG_FILE and CMDARG_COMMAND processing.
	(print_gdb_help): Describe --init-command=FILE, -ix and
	--init-eval-command=COMMAND, -iex.

gdb/doc/
2012-02-25  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.texinfo (File Options): Describe --init-command=FILE, -ix and
	--init-eval-command=COMMAND, -iex.
	(Startup): Describe -iex and -ix.  Simplify the example
	for "set auto-load-scripts off".

gdb/testsuite/
2012-02-25  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.gdb/selftest.exp (do_steps_and_nexts): New entry
	for cmdarg_vec = NULL.  Remove entries for cmdsize = 1, cmdarg = and
	ncmd = 0.  New entry for VEC_cleanup cmdarg_s.

--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -78,6 +78,13 @@ show breakpoint condition-evaluation
   condition evaluation mode.  The use of this extension can be controlled
   via the "set remote conditional-breakpoints-packet" command.
 
+* New command line options
+
+--init-command=FILE, -ix          Like --init-command, -x but execute it
+                                  before loading inferior.
+--init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
+                                  execute it before loading inferior.
+
 *** Changes in GDB 7.4
 
 * GDB now handles ambiguous linespecs more consistently; the existing
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -989,6 +989,20 @@ also be interleaved with @samp{-command} as required.
    -x setbreakpoints -ex 'run' a.out
 @end smallexample
 
+@item -init-command @var{file}
+@itemx -ix @var{file}
+@cindex @code{--init-command}
+@cindex @code{-ix}
+Execute commands from file @var{file} before gdbinit files or inferior loading.
+@xref{Startup}.
+
+@item -init-eval-command @var{command}
+@itemx -iex @var{command}
+@cindex @code{--init-eval-command}
+@cindex @code{-iex}
+Execute a single @value{GDBN} command before gdbinit files or inferior loading.
+@xref{Startup}.
+
 @item -directory @var{directory}
 @itemx -d @var{directory}
 @cindex @code{--directory}
@@ -1234,6 +1248,13 @@ Sets up the command interpreter as specified by the command line
 (@pxref{Mode Options, interpreter}).
 
 @item
+Execute commands and command files specified by the @samp{-iex} and
+@samp{-ix} options in their specified order.  Usually you should use the
+@samp{-ex} and @samp{-x} options instead but this way you can apply
+settings before @value{GDBN} init files get executed and before inferior
+gets loaded.
+
+@item
 @cindex init file
 Reads the system-wide @dfn{init file} (if @option{--with-system-gdbinit} was
 used when building @value{GDBN}; @pxref{System-wide configuration,
@@ -1267,14 +1288,11 @@ If you wish to disable the auto-loading during startup,
 you must do something like the following:
 
 @smallexample
-$ gdb -ex "set auto-load-scripts off" -ex "file myprogram"
+$ gdb -iex "set auto-load-scripts off" myprogram
 @end smallexample
 
-The following does not work because the auto-loading is turned off too late:
-
-@smallexample
-$ gdb -ex "set auto-load-scripts off" myprogram
-@end smallexample
+Option @samp{-ex} does not work because the auto-loading is then turned
+off too late:
 
 @item
 Reads command files specified by the @samp{-x} option.  @xref{Command
--- a/gdb/main.c
+++ b/gdb/main.c
@@ -247,7 +247,13 @@ typedef struct cmdarg {
     CMDARG_FILE,
 
     /* Option type -ex.  */
-    CMDARG_COMMAND
+    CMDARG_COMMAND,
+
+    /* Option type -ix.  */
+    CMDARG_INIT_FILE,
+    
+    /* Option type -iex.  */
+    CMDARG_INIT_COMMAND
   } type;
 
   /* Value of this option - filename or the GDB command itself.  String memory
@@ -394,7 +400,9 @@ captured_main (void *data)
       OPT_STATISTICS,
       OPT_TUI,
       OPT_NOWINDOWS,
-      OPT_WINDOWS
+      OPT_WINDOWS,
+      OPT_IX,
+      OPT_IEX
     };
     static struct option long_options[] =
     {
@@ -434,6 +442,10 @@ captured_main (void *data)
       {"version", no_argument, &print_version, 1},
       {"x", required_argument, 0, 'x'},
       {"ex", required_argument, 0, 'X'},
+      {"init-command", required_argument, 0, OPT_IX},
+      {"init-eval-command", required_argument, 0, OPT_IEX},
+      {"ix", required_argument, 0, OPT_IX},
+      {"iex", required_argument, 0, OPT_IEX},
 #ifdef GDBTK
       {"tclcommand", required_argument, 0, 'z'},
       {"enable-external-editor", no_argument, 0, 'y'},
@@ -555,6 +567,19 @@ captured_main (void *data)
 	      VEC_safe_push (cmdarg_s, cmdarg_vec, &cmdarg);
 	    }
 	    break;
+	  case OPT_IX:
+	    {
+	      struct cmdarg cmdarg = { CMDARG_INIT_FILE, optarg };
+
+	      VEC_safe_push (cmdarg_s, cmdarg_vec, &cmdarg);
+	    }
+	    break;
+	  case OPT_IEX:
+	    {
+	      struct cmdarg cmdarg = { CMDARG_INIT_COMMAND, optarg };
+
+	      VEC_safe_push (cmdarg_s, cmdarg_vec, &cmdarg);
+	    }
 	    break;
 	  case 'B':
 	    batch_flag = batch_silent = 1;
@@ -807,6 +832,20 @@ captured_main (void *data)
   quit_pre_print = error_pre_print;
   warning_pre_print = _("\nwarning: ");
 
+  /* Process '-ix' and '-iex' options early.  */
+  for (i = 0; VEC_iterate (cmdarg_s, cmdarg_vec, i, cmdarg_p); i++)
+    switch (cmdarg_p->type)
+    {
+      case CMDARG_INIT_FILE:
+        catch_command_errors (source_script, cmdarg_p->string,
+			      !batch_flag, RETURN_MASK_ALL);
+	break;
+      case CMDARG_INIT_COMMAND:
+        catch_command_errors (execute_command, cmdarg_p->string,
+			      !batch_flag, RETURN_MASK_ALL);
+	break;
+    }
+
   /* Read and execute the system-wide gdbinit file, if it exists.
      This is done *before* all the command line arguments are
      processed; it sets global parameters, which are independent of
@@ -909,6 +948,7 @@ captured_main (void *data)
   ALL_OBJFILES (objfile)
     load_auto_scripts_for_objfile (objfile);
 
+  /* Process '-x' and '-ex' options.  */
   for (i = 0; VEC_iterate (cmdarg_s, cmdarg_vec, i, cmdarg_p); i++)
     switch (cmdarg_p->type)
     {
@@ -991,6 +1031,8 @@ Options:\n\n\
                      Execute a single GDB command.\n\
                      May be used multiple times and in conjunction\n\
                      with --command.\n\
+  --init-command=FILE, -ix Like -x but execute it before loading inferior.\n\
+  --init-eval-command=COMMAND, -iex Like -ex but before loading inferior.\n\
   --core=COREFILE    Analyze the core dump COREFILE.\n\
   --pid=PID          Attach to running process PID.\n\
 "), stream);
--- a/gdb/testsuite/gdb.gdb/selftest.exp
+++ b/gdb/testsuite/gdb.gdb/selftest.exp
@@ -88,6 +88,10 @@ proc do_steps_and_nexts {} {
 		set description "step over ttyarg initialization"
 		set command "step"
 	    }
+	    -re ".*cmdarg_vec = NULL.*$gdb_prompt $" {
+		set description "step over cmdarg_vec initialization"
+		set command "step"
+	    }
 	    -re ".*pre_stat_chain = make_command_stats_cleanup.*$gdb_prompt $" {
 		set description "next over make_command_stats_cleanup and everything it calls"
 		set command "next"
@@ -124,18 +128,6 @@ proc do_steps_and_nexts {} {
 		set description "next over conditional stack alignment alloca"
 		set command "next"
 	    }
-	    -re ".*cmdsize = 1.*$gdb_prompt $" {
-		set description "step over cmdsize initialization"
-		set command "next"
-	    }
-	    -re ".*cmdarg = .* xmalloc.*$gdb_prompt $" {
-		set description "next over cmdarg initialization via xmalloc"
-		set command "next"
-	    }
-	    -re ".*ncmd = 0.*$gdb_prompt $" {
-		set description "next over ncmd initialization"
-		set command "next"
-	    }
 	    -re ".*dirsize = 1.*$gdb_prompt $" {
 		set description "next over dirsize initialization"
 		set command "next"
@@ -159,6 +151,10 @@ proc do_steps_and_nexts {} {
 		set description "next over textdomain PACKAGE"
 		set command "next"
 	    }
+	    -re ".*VEC_cleanup .cmdarg_s.*$gdb_prompt $" {
+		set description "next over cmdarg_s VEC_cleanup"
+		set command "next"
+	    }
 	    -re "\[0-9\]+\[\t \]+\{\r\n$gdb_prompt $" {
 		set description "step over initial brace"
 		set command "step"