src/keyboard.h

   1 /* Declarations useful when processing input.
   2    Copyright (C) 1985, 1986, 1987, 1993 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 /* Length of echobuf field in each KBOARD.  */
  22
  23 #define ECHOBUFSIZE 300
  24
  25 /* Each KBOARD represents one logical input stream from which Emacs gets input.
  26    If we are using an ordinary terminal, it has one KBOARD object.
  27    Usually each X display screen has its own KBOARD,
  28    but when two of them are on the same X server,
  29    we assume they share a keyboard and give them one KBOARD in common.
  30
  31    Some Lisp variables are per-kboard; they are stored in the KBOARD structure
  32    and accessed indirectly via a Lisp_Misc_Kboard_Objfwd object.
  33
  34    So that definition of keyboard macros, and reading of prefix arguments,
  35    can happen in parallel on various KBOARDs at once,
  36    the state information for those activities is stored in the KBOARD.
  37
  38    Emacs has two states for reading input:
  39
  40    ** Any kboard.  Emacs can accept input from any KBOARD,
  41    and as soon as any of them provides a complete command, Emacs can run it.
  42
  43    ** Single kboard.  Then Emacs is running a command for one KBOARD
  44    and can only read input from that KBOARD.
  45
  46    All input, from all KBOARDs, goes together in a single event queue
  47    at interrupt level.  read_char sees the events sequentially,
  48    but deals with them in accord with the current input state.
  49
  50    In the any-kboard state, read_key_sequence processes input from any KBOARD
  51    immediately.  When a new event comes in from a particular KBOARD,
  52    read_key_sequence switches to that KBOARD.  As a result,
  53    as soon as a complete key arrives from some KBOARD or other,
  54    Emacs starts executing that key's binding.  It switches to the
  55    single-kboard state for the execution of that command,
  56    so that that command can get input only from its own KBOARD.
  57
  58    While in the single-kboard state, read_char can consider input only
  59    from the current KBOARD.  If events come from other KBOARDs, they
  60    are put aside for later in the KBOARDs' kbd_queue lists.
  61    The flag kbd_queue_has_data in a KBOARD is 1 if this has happened.
  62    When Emacs goes back to the any-kboard state, it looks at all the KBOARDs
  63    to find those; and it tries processing their input right away.  */
  64
  65 typedef struct kboard KBOARD;
  66 struct kboard
  67   {
  68     KBOARD *next_kboard;
  69
  70     /* If non-nil, a keymap that overrides all others but applies only to
  71        this KBOARD.  Lisp code that uses this instead of calling read-char
  72        can effectively wait for input in the any-kboard state, and hence
  73        avoid blocking out the other KBOARDs.  See universal-argument in
  74        lisp/simple.el for an example.  */
  75     Lisp_Object Voverriding_terminal_local_map;
  76
  77     /* Last command executed by the editor command loop, not counting
  78        commands that set the prefix argument.  */
  79     Lisp_Object Vlast_command;
  80
  81     /* Normally same as last-command, but never modified by
  82        other commands.  */
  83     Lisp_Object Vreal_last_command;
  84
  85     /* The prefix argument for the next command, in raw form.  */
  86     Lisp_Object Vprefix_arg;
  87
  88     /* Saved prefix argument for the last command, in raw form.  */
  89     Lisp_Object Vlast_prefix_arg;
  90
  91     /* Unread events specific to this kboard.  */
  92     Lisp_Object kbd_queue;
  93
  94     /* Non-nil while a kbd macro is being defined.  */
  95     Lisp_Object defining_kbd_macro;
  96
  97     /* The start of storage for the current keyboard macro.  */
  98     Lisp_Object *kbd_macro_buffer;
  99
 100     /* Where to store the next keystroke of the macro.  */
 101     Lisp_Object *kbd_macro_ptr;
 102
 103     /* The finalized section of the macro starts at kbd_macro_buffer and
 104        ends before this.  This is not the same as kbd_macro_ptr, because
 105        we advance this to kbd_macro_ptr when a key's command is complete.
 106        This way, the keystrokes for "end-kbd-macro" are not included in the
 107        macro.  This also allows us to throw away the events added to the
 108        macro by the last command: all the events between kbd_macro_end and
 109        kbd_macro_ptr belong to the last command; see
 110        cancel-kbd-macro-events.  */
 111     Lisp_Object *kbd_macro_end;
 112
 113     /* Allocated size of kbd_macro_buffer.  */
 114     int kbd_macro_bufsize;
 115
 116     /* Last anonymous kbd macro defined.  */
 117     Lisp_Object Vlast_kbd_macro;
 118
 119     /* Alist of system-specific X windows key symbols.  */
 120     Lisp_Object Vsystem_key_alist;
 121
 122     /* Cache for modify_event_symbol.  */
 123     Lisp_Object system_key_syms;
 124
 125     /* Minibufferless frames on this display use this frame's minibuffer.  */
 126     Lisp_Object Vdefault_minibuffer_frame;
 127
 128     /* Number of displays using this KBOARD.  Normally 1, but can be
 129        larger when you have multiple screens on a single X display.  */
 130     int reference_count;
 131
 132     /* Where to append more text to echobuf if we want to.  */
 133     char *echoptr;
 134
 135     /* The text we're echoing in the modeline - partial key sequences,
 136        usually.  '\0'-terminated.  This really shouldn't have a fixed size.  */
 137     char echobuf[ECHOBUFSIZE];
 138
 139     /* This flag indicates that events were put into kbd_queue
 140        while Emacs was running for some other KBOARD.
 141        The flag means that, when Emacs goes into the any-kboard state again,
 142        it should check this KBOARD to see if there is a complete command
 143        waiting.
 144
 145        Note that the kbd_queue field can be non-nil even when
 146        kbd_queue_has_data is 0.  When we push back an incomplete
 147        command, then this flag is 0, meaning we don't want to try
 148        reading from this KBOARD again until more input arrives.  */
 149     char kbd_queue_has_data;
 150
 151     /* Nonzero means echo each character as typed.  */
 152     char immediate_echo;
 153
 154     /* If we have echoed a prompt string specified by the user,
 155        this is its length.  Otherwise this is -1.  */
 156     char echo_after_prompt;
 157   };
 158
 159 #ifdef MULTI_KBOARD
 160 /* Temporarily used before a frame has been opened, and for termcap frames */
 161 extern KBOARD *initial_kboard;
 162
 163 /* In the single-kboard state, this is the kboard
 164    from which input is accepted.
 165
 166    In the any-kboard state, this is the kboard from which we are
 167    right now considering input.  We can consider input from another
 168    kboard, but doing so requires throwing to wrong_kboard_jmpbuf.  */
 169 extern KBOARD *current_kboard;
 170
 171 /* A list of all kboard objects, linked through next_kboard.  */
 172 extern KBOARD *all_kboards;
 173
 174 /* Nonzero in the single-kboard state, 0 in the any-kboard state.  */
 175 extern int single_kboard;
 176 #else
 177 extern KBOARD the_only_kboard;
 178 #define current_kboard (&the_only_kboard)
 179 #define all_kboards (&the_only_kboard)
 180 #define single_kboard 1
 181 #endif
 182 \f
 183 extern Lisp_Object Vlucid_menu_bar_dirty_flag;
 184 extern Lisp_Object Qrecompute_lucid_menubar, Qactivate_menubar_hook;
 185
 186 /* Total number of times read_char has returned.  */
 187 extern int num_input_events;
 188
 189 /* Total number of times read_char has returned, outside of macros.  */
 190 extern int num_nonmacro_input_events;
 191
 192 /* Nonzero means polling for input is temporarily suppressed.  */
 193 extern int poll_suppress_count;
 194
 195 /* Keymap mapping ASCII function key sequences onto their preferred forms.
 196    Initialized by the terminal-specific lisp files.  */
 197 extern Lisp_Object Vfunction_key_map;
 198
 199 /* Vector holding the key sequence that invoked the current command.
 200    It is reused for each command, and it may be longer than the current
 201    sequence; this_command_key_count indicates how many elements
 202    actually mean something.  */
 203 extern Lisp_Object this_command_keys;
 204 extern int this_command_key_count;
 205
 206 /* The frame in which the last input event occurred, or Qmacro if the
 207    last event came from a macro.  We use this to determine when to
 208    generate switch-frame events.  This may be cleared by functions
 209    like Fselect_frame, to make sure that a switch-frame event is
 210    generated by the next character.  */
 211 extern Lisp_Object internal_last_event_frame;
 212 \f
 213 /* This holds a Lisp vector that holds the properties of a single
 214    menu item while decoding it in parse_menu_item.
 215    Using a Lisp vector to hold this information while we decode it
 216    takes care of protecting all the data from GC.  */
 217 extern Lisp_Object item_properties;
 218
 219 /* This describes the elements of item_properties.
 220    The first element is not a property, it is a pointer to the item properties
 221    that is saved for GC protection. */
 222 #define ITEM_PROPERTY_ITEM 0
 223 /* The item string.  */
 224 #define ITEM_PROPERTY_NAME 1
 225 /* Start of initialize to nil */
 226 /* The binding: nil, a command or a keymap.  */
 227 #define ITEM_PROPERTY_DEF 2
 228 /* The keymap if the binding is a keymap, otherwise nil.  */
 229 #define ITEM_PROPERTY_MAP 3
 230 /* Nil, :radio or :toggle.  */
 231 #define ITEM_PROPERTY_TYPE 4
 232 /* Nil or a string describing an equivalent key binding.  */
 233 #define ITEM_PROPERTY_KEYEQ 5
 234 /* Not nil if a selected toggle box or radio button, otherwise nil.  */
 235 #define ITEM_PROPERTY_SELECTED 6
 236 /* Place for a help string. Not yet used.  */
 237 #define ITEM_PROPERTY_HELP 7
 238 /* Start of initialize to t */
 239 /* Last property. */
 240 /* Not nil if item is enabled.  */
 241 #define ITEM_PROPERTY_ENABLE 8
 242 \f
 243 /* Macros for dealing with lispy events.  */
 244
 245 /* True iff EVENT has data fields describing it (i.e. a mouse click).  */
 246 #define EVENT_HAS_PARAMETERS(event) (CONSP (event))
 247
 248 /* Extract the head from an event.
 249    This works on composite and simple events.  */
 250 #define EVENT_HEAD(event) \
 251   (EVENT_HAS_PARAMETERS (event) ? XCAR (event) : (event))
 252
 253 /* Extract the starting and ending positions from a composite event.  */
 254 #define EVENT_START(event) (XCAR (XCDR (event)))
 255 #define EVENT_END(event) (XCAR (XCDR (XCDR (event))))
 256
 257 /* Extract the click count from a multi-click event.  */
 258 #define EVENT_CLICK_COUNT(event) (Fnth ((event), make_number (2)))
 259
 260 /* Extract the fields of a position.  */
 261 #define POSN_WINDOW(posn) (XCAR (posn))
 262 #define POSN_BUFFER_POSN(posn) (XCAR (XCDR (posn)))
 263 #define POSN_BUFFER_SET_POSN(posn,x) (XSETCAR (XCDR (posn), (x)))
 264 #define POSN_WINDOW_POSN(posn) (XCAR (XCDR (XCDR (posn))))
 265 #define POSN_TIMESTAMP(posn) \
 266   (XCAR (XCDR (XCDR (XCDR (posn)))))
 267 #define POSN_SCROLLBAR_PART(posn)       (Fnth ((posn), make_number (4)))
 268
 269 /* A cons (STRING . STRING-CHARPOS), or nil in mouse-click events.
 270    It's a cons if the click is over a string in the mode line.  */
 271
 272 #define POSN_STRING(POSN) Fnth (make_number (4), (POSN))
 273
 274 /* Some of the event heads.  */
 275 extern Lisp_Object Qswitch_frame;
 276
 277 /* Properties on event heads.  */
 278 extern Lisp_Object Qevent_kind, Qevent_symbol_elements;
 279
 280 /* Getting an unmodified version of an event head.  */
 281 #define EVENT_HEAD_UNMODIFIED(event_head) \
 282   (Fcar (Fget ((event_head), Qevent_symbol_elements)))
 283
 284 /* The values of Qevent_kind properties.  */
 285 extern Lisp_Object Qfunction_key, Qmouse_click, Qmouse_movement;
 286 extern Lisp_Object Qscroll_bar_movement;
 287
 288 /* Getting the kind of an event head.  */
 289 #define EVENT_HEAD_KIND(event_head) \
 290   (Fget ((event_head), Qevent_kind))
 291
 292 /* Symbols to use for non-text mouse positions.  */
 293 extern Lisp_Object Qmode_line, Qvertical_line, Qheader_line;
 294
 295 /* Forward declaration for prototypes.  */
 296 struct input_event;
 297
 298 extern Lisp_Object parse_modifiers P_ ((Lisp_Object));
 299 extern Lisp_Object reorder_modifiers P_ ((Lisp_Object));
 300 extern Lisp_Object read_char P_ ((int, int, Lisp_Object *, Lisp_Object, int *));
 301 /* User-supplied string to translate input characters through.  */
 302 extern Lisp_Object Vkeyboard_translate_table;
 303
 304
 305 extern int parse_menu_item P_ ((Lisp_Object, int, int));
 306
 307 extern void echo_now P_ ((void));
 308 extern void init_kboard P_ ((KBOARD *));
 309 extern void delete_kboard P_ ((KBOARD *));
 310 extern void single_kboard_state P_ ((void));
 311 extern void push_frame_kboard P_ ((struct frame *));
 312 extern void pop_frame_kboard P_ ((void));
 313 extern void record_asynch_buffer_change P_ ((void));
 314 extern SIGTYPE input_poll_signal P_ ((int));
 315 extern void start_polling P_ ((void));
 316 extern void stop_polling P_ ((void));
 317 extern void set_poll_suppress_count P_ ((int));
 318 extern void gobble_input P_ ((int));
 319 extern int input_polling_used P_ ((void));
 320 extern void clear_input_pending P_ ((void));
 321 extern int requeued_events_pending_p P_ ((void));
 322 extern void bind_polling_period P_ ((int));
 323 extern void stuff_buffered_input P_ ((Lisp_Object));
 324 extern void clear_waiting_for_input P_ ((void));
 325 extern void swallow_events P_ ((int));
 326 extern int help_char_p P_ ((Lisp_Object));
 327 extern void quit_throw_to_read_char P_ ((void)) NO_RETURN;
 328 extern void cmd_error_internal P_ ((Lisp_Object, char *));
 329 extern void timer_start_idle P_ ((void));
 330 extern void timer_stop_idle P_ ((void));
 331 extern int lucid_event_type_list_p P_ ((Lisp_Object));
 332 extern void kbd_buffer_store_event P_ ((struct input_event *));
 333 #ifdef POLL_FOR_INPUT
 334 extern void poll_for_input_1 P_ ((void));
 335 #endif
 336 extern void show_help_echo P_ ((Lisp_Object, Lisp_Object, Lisp_Object,
 337                                 Lisp_Object, int));
 338 extern int gen_help_event P_ ((struct input_event *, int, Lisp_Object,
 339                                Lisp_Object, Lisp_Object, Lisp_Object, int));
 340 extern void kbd_buffer_store_help_event P_ ((Lisp_Object, Lisp_Object));
 341 extern Lisp_Object menu_item_eval_property P_ ((Lisp_Object));
 342 extern int  kbd_buffer_events_waiting P_ ((int));