gdb/event-top.h

   1 /* Definitions used by GDB event-top.c.
   2    Copyright 1999 Free Software Foundation, Inc.
   3    Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 /* Stack for prompts. Each prompt is composed as a prefix, a prompt
  23    and a suffix. The prompt to be displayed at any given time is the
  24    one on top of the stack.  A stack is necessary because of cases in
  25    which the execution of a gdb command requires further input from
  26    the user, like for instance 'commands' for breakpoints and
  27    'actions' for tracepoints. In these cases, the prompt is '>' and
  28    gdb should process input using the asynchronous readline interface
  29    and the event loop.  In order to achieve this, we need to save
  30    somewhere the state of GDB, i.e. that it is processing user input
  31    as part of a command and not as part of the top level command loop.
  32    The prompt stack represents part of the saved state. Another part
  33    would be the function that readline would invoke after a whole line
  34    of input has ben entered. This second piece would be something
  35    like, for instance, where to return within the code for the actions
  36    commands after a line has been read.  This latter portion has not
  37    beeen implemented yet.  The need for a 3-part prompt arises from
  38    the annotation level. When this is set to 2, the prompt is actually
  39    composed of a prefix, the prompt itself and a suffix. */
  40
  41 /* At any particular time there will be always at least one prompt on
  42    the stack, the one being currently displayed by gdb. If gdb is
  43    using annotation level equal 2, there will be 2 prompts on the
  44    stack: the usual one, w/o prefix and suffix (at top - 1), and the
  45    'composite' one with prefix and suffix added (at top). At this
  46    time, this is the only use of the prompt stack. Resetting annotate
  47    to 0 or 1, pops the top of the stack, resetting its size to one
  48    element. The MAXPROMPTS limit is safe, for now. Once other cases
  49    are dealt with (like the different prompts used for 'commands' or
  50    'actions') this array implementation of the prompt stack may have
  51    to change. */
  52
  53 #define MAXPROMPTS 10
  54 struct prompts
  55   {
  56     struct
  57       {
  58         char *prefix;
  59         char *prompt;
  60         char *suffix;
  61       }
  62     prompt_stack[MAXPROMPTS];
  63     int top;
  64   };
  65
  66 #define PROMPT(X) the_prompts.prompt_stack[the_prompts.top + X].prompt
  67 #define PREFIX(X) the_prompts.prompt_stack[the_prompts.top + X].prefix
  68 #define SUFFIX(X) the_prompts.prompt_stack[the_prompts.top + X].suffix
  69
  70 /* Exported functions from event-top.c.
  71    FIXME: these should really go into top.h. */
  72
  73 extern void display_gdb_prompt (char *new_prompt);
  74 extern void async_init_signals (void);
  75 extern void set_async_editing_command (char *args, int from_tty, struct cmd_list_element *c);
  76 extern void set_async_annotation_level (char *args, int from_tty, struct cmd_list_element *c);
  77 extern void set_async_prompt (char *args, int from_tty, struct cmd_list_element *c);
  78
  79 /* Signal to catch ^Z typed while reading a command: SIGTSTP or SIGCONT.  */
  80 #ifndef STOP_SIGNAL
  81 #ifdef SIGTSTP
  82 #define STOP_SIGNAL SIGTSTP
  83 extern void handle_stop_sig (int sig);
  84 #endif
  85 #endif
  86 extern void handle_sigint (int sig);
  87 extern void pop_prompt (void);
  88 extern void push_prompt (char *prefix, char *prompt, char *suffix);
  89 extern void gdb_readline2 (void *client_data);
  90 extern void mark_async_signal_handler_wrapper (void *token);
  91 extern void async_request_quit (void *arg);
  92 extern void stdin_event_handler (int error, void *client_data);
  93 extern void async_disable_stdin (void);
  94 extern void async_enable_stdin (void *dummy);
  95
  96 /* Exported variables from event-top.c.
  97    FIXME: these should really go into top.h. */
  98
  99 extern int async_command_editing_p;
 100 extern int exec_done_display_p;
 101 extern char *async_annotation_suffix;
 102 extern char *new_async_prompt;
 103 extern struct prompts the_prompts;
 104 extern void (*call_readline) (void *);
 105 extern void (*input_handler) (char *);
 106 extern int input_fd;