Update more calls to add_prefix_cmd

I looked at all the calls to add_prefix_cmd, and replaced them with
calls to add_basic_prefix_cmd or add_show_prefix_cmd when appropriate.
This makes gdb's command language a bit more regular.  I don't think
there's a significant downside.

Note that this patch removes a couple of tests.  The removed ones are
completely redundant.

gdb/ChangeLog
2020-05-03  Tom Tromey  <tom@tromey.com>

	* breakpoint.c (catch_command, tcatch_command): Remove.
	(_initialize_breakpoint): Use add_basic_prefix_cmd,
	add_show_prefix_cmd.
	(set_breakpoint_cmd, show_breakpoint_cmd): Remove
	* utils.c (set_internal_problem_cmd, show_internal_problem_cmd):
	Remove.
	(add_internal_problem_command): Use add_basic_prefix_cmd,
	add_show_prefix_cmd.
	* mips-tdep.c (set_mipsfpu_command): Remove.
	(_initialize_mips_tdep): Use add_basic_prefix_cmd.
	* dwarf2/index-cache.c (set_index_cache_command): Remove.
	(_initialize_index_cache): Use add_basic_prefix_cmd.
	* memattr.c (dummy_cmd): Remove.
	(_initialize_mem): Use add_basic_prefix_cmd, add_show_prefix_cmd.
	* tui/tui-win.c (set_tui_cmd, show_tui_cmd): Remove.
	(_initialize_tui_win): Use add_basic_prefix_cmd,
	add_show_prefix_cmd.
	* cli/cli-logging.c (set_logging_command): Remove.
	(_initialize_cli_logging): Use add_basic_prefix_cmd,
	add_show_prefix_cmd.
	(show_logging_command): Remove.
	* target.c (target_command): Remove.
	(add_target): Use add_basic_prefix_cmd.

gdb/testsuite/ChangeLog
2020-05-03  Tom Tromey  <tom@tromey.com>

	* gdb.base/sepdebug.exp: Remove "catch" test.
	* gdb.base/break.exp: Remove "catch" test.
	* gdb.base/default.exp: Update expected output.

gdb/ChangeLog

@@ -1,3 +1,29 @@
+2020-05-03  Tom Tromey  <tom@tromey.com>
+
+	* breakpoint.c (catch_command, tcatch_command): Remove.
+	(_initialize_breakpoint): Use add_basic_prefix_cmd,
+	add_show_prefix_cmd.
+	(set_breakpoint_cmd, show_breakpoint_cmd): Remove
+	* utils.c (set_internal_problem_cmd, show_internal_problem_cmd):
+	Remove.
+	(add_internal_problem_command): Use add_basic_prefix_cmd,
+	add_show_prefix_cmd.
+	* mips-tdep.c (set_mipsfpu_command): Remove.
+	(_initialize_mips_tdep): Use add_basic_prefix_cmd.
+	* dwarf2/index-cache.c (set_index_cache_command): Remove.
+	(_initialize_index_cache): Use add_basic_prefix_cmd.
+	* memattr.c (dummy_cmd): Remove.
+	(_initialize_mem): Use add_basic_prefix_cmd, add_show_prefix_cmd.
+	* tui/tui-win.c (set_tui_cmd, show_tui_cmd): Remove.
+	(_initialize_tui_win): Use add_basic_prefix_cmd,
+	add_show_prefix_cmd.
+	* cli/cli-logging.c (set_logging_command): Remove.
+	(_initialize_cli_logging): Use add_basic_prefix_cmd,
+	add_show_prefix_cmd.
+	(show_logging_command): Remove.
+	* target.c (target_command): Remove.
+	(add_target): Use add_basic_prefix_cmd.
+
 2020-05-02  Hannes Domani  <ssbssa@yahoo.de>
 
 	* gdbtypes.h (enum dynamic_prop_node_kind): Fix typo.

gdb/breakpoint.c

@@ -11214,19 +11214,8 @@ init_ada_exception_breakpoint (struct breakpoint *b,
   b->language = language_ada;
 }
 
-static void
-catch_command (const char *arg, int from_tty)
-{
-  error (_("Catch requires an event name."));
-}
 
 
-static void
-tcatch_command (const char *arg, int from_tty)
-{
-  error (_("Catch requires an event name."));
-}
-
 /* Compare two breakpoints and return a strcmp-like result.  */
 
 static int
@@ -14335,16 +14324,6 @@ enable_delete_command (const char *args, int from_tty)
      });
 }
 
-static void
-set_breakpoint_cmd (const char *args, int from_tty)
-{
-}
-
-static void
-show_breakpoint_cmd (const char *args, int from_tty)
-{
-}
-
 /* Invalidate last known value of any hardware watchpoint if
    the memory which that value represents has been written to by
    GDB itself.  */
@@ -15614,12 +15593,12 @@ Convenience variable \"$bpnum\" contains the number of the last\n\
 breakpoint set."),
 	   &maintenanceinfolist);
 
-  add_prefix_cmd ("catch", class_breakpoint, catch_command, _("\
+  add_basic_prefix_cmd ("catch", class_breakpoint, _("\
 Set catchpoints to catch events."),
 			&catch_cmdlist, "catch ",
 			0/*allow-unknown*/, &cmdlist);
 
-  add_prefix_cmd ("tcatch", class_breakpoint, tcatch_command, _("\
+  add_basic_prefix_cmd ("tcatch", class_breakpoint, _("\
 Set temporary catchpoints to catch events."),
 			&tcatch_cmdlist, "tcatch ",
 			0/*allow-unknown*/, &cmdlist);
@@ -15799,13 +15778,13 @@ Use the 'source' command in another debug session to restore them."),
   c = add_com_alias ("save-tracepoints", "save tracepoints", class_trace, 0);
   deprecate_cmd (c, "save tracepoints");
 
-  add_prefix_cmd ("breakpoint", class_maintenance, set_breakpoint_cmd, _("\
+  add_basic_prefix_cmd ("breakpoint", class_maintenance, _("\
 Breakpoint specific settings.\n\
 Configure various breakpoint-specific variables such as\n\
 pending breakpoint behavior."),
 			&breakpoint_set_cmdlist, "set breakpoint ",
 			0/*allow-unknown*/, &setlist);
-  add_prefix_cmd ("breakpoint", class_maintenance, show_breakpoint_cmd, _("\
+  add_show_prefix_cmd ("breakpoint", class_maintenance, _("\
 Breakpoint specific settings.\n\
 Configure various breakpoint-specific variables such as\n\
 pending breakpoint behavior."),

gdb/cli/cli-logging.c

@@ -165,53 +165,16 @@ set_logging_off (const char *args, int from_tty)
   saved_filename = NULL;
 }
 
-static void
-set_logging_command (const char *args, int from_tty)
-{
-  printf_unfiltered (_("\"set logging\" lets you log output to a file.\n"
-		       "Usage: set logging on [FILENAME]\n"
-		       "       set logging off\n"
-		       "       set logging file FILENAME\n"
-		       "       set logging overwrite [on|off]\n"
-		       "       set logging redirect [on|off]\n"));
-}
-
-static void
-show_logging_command (const char *args, int from_tty)
-{
-  if (saved_filename)
-    printf_unfiltered (_("Currently logging to \"%s\".\n"), saved_filename);
-  if (saved_filename == NULL
-      || strcmp (logging_filename, saved_filename) != 0)
-    printf_unfiltered (_("Future logs will be written to %s.\n"),
-		       logging_filename);
-
-  if (logging_overwrite)
-    printf_unfiltered (_("Logs will overwrite the log file.\n"));
-  else
-    printf_unfiltered (_("Logs will be appended to the log file.\n"));
-
-  if (logging_redirect)
-    printf_unfiltered (_("Output will be sent only to the log file.\n"));
-  else
-    printf_unfiltered (_("Output will be logged and displayed.\n"));
-
-  if (debug_redirect)
-    printf_unfiltered (_("Debug output will be sent only to the log file.\n"));
-  else
-    printf_unfiltered (_("Debug output will be logged and displayed.\n"));
-}
-
 void _initialize_cli_logging ();
 void
 _initialize_cli_logging ()
 {
   static struct cmd_list_element *set_logging_cmdlist, *show_logging_cmdlist;
 
-  add_prefix_cmd ("logging", class_support, set_logging_command,
+  add_basic_prefix_cmd ("logging", class_support,
 			_("Set logging options."), &set_logging_cmdlist,
 			"set logging ", 0, &setlist);
-  add_prefix_cmd ("logging", class_support, show_logging_command,
+  add_show_prefix_cmd ("logging", class_support,
 		       _("Show logging options."), &show_logging_cmdlist,
 		       "show logging ", 0, &showlist);
   add_setshow_boolean_cmd ("overwrite", class_support, &logging_overwrite, _("\

gdb/dwarf2/index-cache.c

@@ -246,15 +246,6 @@ index_cache::make_index_filename (const bfd_build_id *build_id,
   return m_dir + SLASH_STRING + build_id_str + suffix;
 }
 
-/* "set index-cache" handler.  */
-
-static void
-set_index_cache_command (const char *arg, int from_tty)
-{
-  printf_unfiltered (_("\
-Missing arguments.  See \"help set index-cache\" for help.\n"));
-}
-
 /* True when we are executing "show index-cache".  This is used to improve the
    printout a little bit.  */
 static bool in_show_index_cache_command = false;
@@ -341,8 +332,9 @@ _initialize_index_cache ()
     warning (_("Couldn't determine a path for the index cache directory."));
 
   /* set index-cache */
-  add_prefix_cmd ("index-cache", class_files, set_index_cache_command,
+  add_basic_prefix_cmd ("index-cache", class_files,
-		  _("Set index-cache options."), &set_index_cache_prefix_list,
+			_("Set index-cache options."),
+			&set_index_cache_prefix_list,
 			"set index-cache ", false, &setlist);
 
   /* show index-cache */

gdb/memattr.c

@@ -586,11 +586,6 @@ delete_mem_command (const char *args, int from_tty)
   dont_repeat ();
 }
 
-static void
-dummy_cmd (const char *args, int from_tty)
-{
-}
-
 static struct cmd_list_element *mem_set_cmdlist;
 static struct cmd_list_element *mem_show_cmdlist;
 
@@ -628,11 +623,11 @@ Do \"info mem\" to see current list of IDs."), &deletelist);
   add_info ("mem", info_mem_command,
 	    _("Memory region attributes."));
 
-  add_prefix_cmd ("mem", class_vars, dummy_cmd, _("\
+  add_basic_prefix_cmd ("mem", class_vars, _("\
 Memory regions settings."),
 			&mem_set_cmdlist, "set mem ",
 			0/* allow-unknown */, &setlist);
-  add_prefix_cmd ("mem", class_vars, dummy_cmd, _("\
+  add_show_prefix_cmd ("mem", class_vars, _("\
 Memory regions settings."),
 		       &mem_show_cmdlist, "show mem  ",
 		       0/* allow-unknown */, &showlist);

gdb/mips-tdep.c

@@ -6916,14 +6916,6 @@ show_mipsfpu_command (const char *args, int from_tty)
 }
 
 
-static void
-set_mipsfpu_command (const char *args, int from_tty)
-{
-  printf_unfiltered ("\"set mipsfpu\" must be followed by \"double\", "
-		     "\"single\",\"none\" or \"auto\".\n");
-  show_mipsfpu_command (args, from_tty);
-}
-
 static void
 set_mipsfpu_single_command (const char *args, int from_tty)
 {
@@ -9018,7 +9010,7 @@ and is updated automatically from ELF file flags if available."),
   /* Let the user turn off floating point and set the fence post for
      heuristic_proc_start.  */
 
-  add_prefix_cmd ("mipsfpu", class_support, set_mipsfpu_command,
+  add_basic_prefix_cmd ("mipsfpu", class_support,
 			_("Set use of MIPS floating-point coprocessor."),
 			&mipsfpulist, "set mipsfpu ", 0, &setlist);
   add_cmd ("single", class_support, set_mipsfpu_single_command,

gdb/target.c

@@ -168,15 +168,6 @@ show_targetdebug (struct ui_file *file, int from_tty,
   fprintf_filtered (file, _("Target debugging is %s.\n"), value);
 }
 
-/* The user just typed 'target' without the name of a target.  */
-
-static void
-target_command (const char *arg, int from_tty)
-{
-  fputs_filtered ("Argument required (target name).  Try `help target'\n",
-		  gdb_stdout);
-}
-
 int
 target_has_all_memory_1 (void)
 {
@@ -269,7 +260,7 @@ add_target (const target_info &t, target_open_ftype *func,
   func_slot = func;
 
   if (targetlist == NULL)
-    add_prefix_cmd ("target", class_run, target_command, _("\
+    add_basic_prefix_cmd ("target", class_run, _("\
 Connect to a target machine or process.\n\
 The first argument is the type or protocol of the target machine.\n\
 Remaining arguments are interpreted by the target protocol.  For more\n\

gdb/testsuite/ChangeLog

@@ -1,3 +1,9 @@
+2020-05-03  Tom Tromey  <tom@tromey.com>
+
+	* gdb.base/sepdebug.exp: Remove "catch" test.
+	* gdb.base/break.exp: Remove "catch" test.
+	* gdb.base/default.exp: Update expected output.
+
 2020-05-02  Tom de Vries  <tdevries@suse.de>
 
 	* lib/gdb.exp (supports_mpx_check_pointer_bounds): New proc.

gdb/testsuite/gdb.base/break.exp

@@ -469,10 +469,6 @@ gdb_test "info break" "Num     Type.*Disp Enb Address.*What.*\[\r\n\]
 #
 if ![runto_main] then { fail "break tests suppressed" }
 
-gdb_test "catch" \
-    "Catch requires an event name." \
-    "catch requires an event name"
-
 gdb_test "catch fork" "Catchpoint \[0-9\]+ \\(fork\\)" \
     "set catch fork, never expected to trigger"
 

gdb/testsuite/gdb.base/default.exp

@@ -78,7 +78,7 @@ gdb_test "call" "The history is empty..*"
 
 
 #test catch
-gdb_test "catch" "Catch requires an event name..*"
+gdb_test "catch" "List of catch subcommands:(\[^\r\n\]*\[\r\n\])+Type \"help catch\" followed by catch subcommand name for full documentation.(\[^\r\n\]*\[\r\n\])+Command name abbreviations are allowed if unambiguous."
 
 #test cd
 gdb_test "cd" "Working directory \[^\r\n\]*\(\r\n \\(canonically \[^\r\n\]*\\)\)?\\."
@@ -794,7 +794,7 @@ gdb_expect {
 }
 
 #test target
-gdb_test "target" "Argument required .target name.*"
+gdb_test "target" "List of target subcommands:(\[^\r\n\]*\[\r\n\])+Type \"help target\" followed by target subcommand name for full documentation.(\[^\r\n\]*\[\r\n\])+Command name abbreviations are allowed if unambiguous."
 #test tbreak
 gdb_test "tbreak" "No default breakpoint address now."
 #test thread

gdb/testsuite/gdb.base/sepdebug.exp

@@ -280,9 +280,6 @@ gdb_test "info break" "Num     Type.*Disp Enb Address.*What.*\[\r\n\]
 #
 if ![runto_main] then { fail "sepdebug tests suppressed" }
 
-gdb_test "catch" "Catch requires an event name.*" \
-    "catch requires an event name"
-
 gdb_test "catch fork" "Catchpoint \[0-9\]+ \\(fork\\)" \
     "set catch fork, never expected to trigger"
 

gdb/tui/tui-win.c

@@ -298,16 +298,6 @@ tui_update_variables ()
   return need_redraw;
 }
 
-static void
-set_tui_cmd (const char *args, int from_tty)
-{
-}
-
-static void
-show_tui_cmd (const char *args, int from_tty)
-{
-}
-
 static struct cmd_list_element *tuilist;
 
 struct cmd_list_element **
@@ -1004,11 +994,11 @@ _initialize_tui_win ()
 
   /* Define the classes of commands.
      They will appear in the help list in the reverse of this order.  */
-  add_prefix_cmd ("tui", class_tui, set_tui_cmd,
+  add_basic_prefix_cmd ("tui", class_tui,
 			_("TUI configuration variables."),
 			&tui_setlist, "set tui ",
 			0 /* allow-unknown */, &setlist);
-  add_prefix_cmd ("tui", class_tui, show_tui_cmd,
+  add_show_prefix_cmd ("tui", class_tui,
 		       _("TUI configuration variables."),
 		       &tui_showlist, "show tui ",
 		       0 /* allow-unknown */, &showlist);

gdb/utils.c

@@ -469,18 +469,6 @@ demangler_warning (const char *file, int line, const char *string, ...)
   va_end (ap);
 }
 
-/* Dummy functions to keep add_prefix_cmd happy.  */
-
-static void
-set_internal_problem_cmd (const char *args, int from_tty)
-{
-}
-
-static void
-show_internal_problem_cmd (const char *args, int from_tty)
-{
-}
-
 /* When GDB reports an internal problem (error or warning) it gives
    the user the opportunity to quit GDB and/or create a core file of
    the current debug session.  This function registers a few commands
@@ -515,15 +503,13 @@ add_internal_problem_command (struct internal_problem *problem)
   show_doc = xstrprintf (_("Show what GDB does when %s is detected."),
 			 problem->name);
 
-  add_prefix_cmd (problem->name,
+  add_basic_prefix_cmd (problem->name, class_maintenance, set_doc,
-		  class_maintenance, set_internal_problem_cmd, set_doc,
 			set_cmd_list,
 			concat ("maintenance set ", problem->name, " ",
 				(char *) NULL),
 			0/*allow-unknown*/, &maintenance_set_cmdlist);
 
-  add_prefix_cmd (problem->name,
+  add_show_prefix_cmd (problem->name, class_maintenance, show_doc,
-		  class_maintenance, show_internal_problem_cmd, show_doc,
 		       show_cmd_list,
 		       concat ("maintenance show ", problem->name, " ",
 			       (char *) NULL),