src/keyboard.h

   1 /* Declarations useful when processing input.
   2    Copyright (C) 1985, 1986, 1987, 1993, 2002, 2003, 2004,
   3                  2005 Free Software Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs 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, or (at your option)
  10 any later version.
  11
  12 GNU Emacs 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 GNU Emacs; see the file COPYING.  If not, write to
  19 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 /* Length of echobuf field in each KBOARD.  */
  23
  24 /* Each KBOARD represents one logical input stream from which Emacs gets input.
  25    If we are using ordinary terminals, it has one KBOARD object for each terminal device.
  26    Usually each X display screen has its own KBOARD,
  27    but when two of them are on the same X server,
  28    we assume they share a keyboard and give them one KBOARD in common.
  29
  30    Some Lisp variables are per-kboard; they are stored in the KBOARD structure
  31    and accessed indirectly via a Lisp_Misc_Kboard_Objfwd object.
  32
  33    So that definition of keyboard macros, and reading of prefix arguments,
  34    can happen in parallel on various KBOARDs at once,
  35    the state information for those activities is stored in the KBOARD.
  36
  37    Emacs has two states for reading input:
  38
  39    ** Any kboard.  Emacs can accept input from any KBOARD,
  40    and as soon as any of them provides a complete command, Emacs can run it.
  41
  42    ** Single kboard.  Then Emacs is running a command for one KBOARD
  43    and can only read input from that KBOARD.
  44
  45    All input, from all KBOARDs, goes together in a single event queue
  46    at interrupt level.  read_char sees the events sequentially,
  47    but deals with them in accord with the current input state.
  48
  49    In the any-kboard state, read_key_sequence processes input from any KBOARD
  50    immediately.  When a new event comes in from a particular KBOARD,
  51    read_key_sequence switches to that KBOARD.  As a result,
  52    as soon as a complete key arrives from some KBOARD or other,
  53    Emacs starts executing that key's binding.  It switches to the
  54    single-kboard state for the execution of that command,
  55    so that that command can get input only from its own KBOARD.
  56
  57    While in the single-kboard state, read_char can consider input only
  58    from the current KBOARD.  If events come from other KBOARDs, they
  59    are put aside for later in the KBOARDs' kbd_queue lists.
  60    The flag kbd_queue_has_data in a KBOARD is 1 if this has happened.
  61    When Emacs goes back to the any-kboard state, it looks at all the KBOARDs
  62    to find those; and it tries processing their input right away.  */
  63
  64 typedef struct kboard KBOARD;
  65 struct kboard
  66   {
  67     KBOARD *next_kboard;
  68
  69     /* If non-nil, a keymap that overrides all others but applies only to
  70        this KBOARD.  Lisp code that uses this instead of calling read-char
  71        can effectively wait for input in the any-kboard state, and hence
  72        avoid blocking out the other KBOARDs.  See universal-argument in
  73        lisp/simple.el for an example.  */
  74     Lisp_Object Voverriding_terminal_local_map;
  75
  76     /* Last command executed by the editor command loop, not counting
  77        commands that set the prefix argument.  */
  78     Lisp_Object Vlast_command;
  79
  80     /* Normally same as last-command, but never modified by
  81        other commands.  */
  82     Lisp_Object Vreal_last_command;
  83
  84     /* The prefix argument for the next command, in raw form.  */
  85     Lisp_Object Vprefix_arg;
  86
  87     /* Saved prefix argument for the last command, in raw form.  */
  88     Lisp_Object Vlast_prefix_arg;
  89
  90     /* Unread events specific to this kboard.  */
  91     Lisp_Object kbd_queue;
  92
  93     /* Non-nil while a kbd macro is being defined.  */
  94     Lisp_Object defining_kbd_macro;
  95
  96     /* The start of storage for the current keyboard macro.  */
  97     Lisp_Object *kbd_macro_buffer;
  98
  99     /* Where to store the next keystroke of the macro.  */
 100     Lisp_Object *kbd_macro_ptr;
 101
 102     /* The finalized section of the macro starts at kbd_macro_buffer and
 103        ends before this.  This is not the same as kbd_macro_ptr, because
 104        we advance this to kbd_macro_ptr when a key's command is complete.
 105        This way, the keystrokes for "end-kbd-macro" are not included in the
 106        macro.  This also allows us to throw away the events added to the
 107        macro by the last command: all the events between kbd_macro_end and
 108        kbd_macro_ptr belong to the last command; see
 109        cancel-kbd-macro-events.  */
 110     Lisp_Object *kbd_macro_end;
 111
 112     /* Allocated size of kbd_macro_buffer.  */
 113     int kbd_macro_bufsize;
 114
 115     /* Last anonymous kbd macro defined.  */
 116     Lisp_Object Vlast_kbd_macro;
 117
 118     /* Alist of system-specific X windows key symbols.  */
 119     Lisp_Object Vsystem_key_alist;
 120
 121     /* Cache for modify_event_symbol.  */
 122     Lisp_Object system_key_syms;
 123
 124     /* Keymap mapping ASCII function key sequences onto their
 125        preferred forms.  Initialized by the terminal-specific lisp
 126        files.  See the DEFVAR for more documentation.  */
 127     Lisp_Object Vlocal_function_key_map;
 128
 129     /* Keymap of key translations that can override keymaps.  */
 130     Lisp_Object Vlocal_key_translation_map;
 131
 132     /* Minibufferless frames on this display use this frame's minibuffer.  */
 133     Lisp_Object Vdefault_minibuffer_frame;
 134
 135     /* Number of displays using this KBOARD.  Normally 1, but can be
 136        larger when you have multiple screens on a single X display.  */
 137     int reference_count;
 138
 139     /* The text we're echoing in the modeline - partial key sequences,
 140        usually.  This is nil when not echoing.  */
 141     Lisp_Object echo_string;
 142
 143     /* This flag indicates that events were put into kbd_queue
 144        while Emacs was running for some other KBOARD.
 145        The flag means that, when Emacs goes into the any-kboard state again,
 146        it should check this KBOARD to see if there is a complete command
 147        waiting.
 148
 149        Note that the kbd_queue field can be non-nil even when
 150        kbd_queue_has_data is 0.  When we push back an incomplete
 151        command, then this flag is 0, meaning we don't want to try
 152        reading from this KBOARD again until more input arrives.  */
 153     char kbd_queue_has_data;
 154
 155     /* Nonzero means echo each character as typed.  */
 156     char immediate_echo;
 157
 158     /* If we have echoed a prompt string specified by the user,
 159        this is its length in characters.  Otherwise this is -1.  */
 160     char echo_after_prompt;
 161   };
 162
 163 #ifdef MULTI_KBOARD
 164 /* Temporarily used before a frame has been opened. */
 165 extern KBOARD *initial_kboard;
 166
 167 /* In the single-kboard state, this is the kboard
 168    from which input is accepted.
 169
 170    In the any-kboard state, this is the kboard from which we are
 171    right now considering input.  We can consider input from another
 172    kboard, but doing so requires throwing to wrong_kboard_jmpbuf.  */
 173 extern KBOARD *current_kboard;
 174
 175 /* A list of all kboard objects, linked through next_kboard.  */
 176 extern KBOARD *all_kboards;
 177
 178 /* Nonzero in the single-kboard state, 0 in the any-kboard state.  */
 179 extern int single_kboard;
 180 #else
 181 extern KBOARD the_only_kboard;
 182 #define current_kboard (&the_only_kboard)
 183 #define all_kboards (&the_only_kboard)
 184 #define single_kboard 1
 185 #endif
 186 \f
 187 extern Lisp_Object Vlucid_menu_bar_dirty_flag;
 188 extern Lisp_Object Qrecompute_lucid_menubar, Qactivate_menubar_hook;
 189
 190 /* Total number of times read_char has returned.  */
 191 extern int num_input_events;
 192
 193 /* Total number of times read_char has returned, outside of macros.  */
 194 extern EMACS_INT num_nonmacro_input_events;
 195
 196 /* Nonzero means polling for input is temporarily suppressed.  */
 197 extern int poll_suppress_count;
 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 (make_number (2), (event)))
 259
 260 /* Extract the fields of a position.  */
 261 #define POSN_WINDOW(posn) (XCAR (posn))
 262 #define POSN_POSN(posn) (XCAR (XCDR (posn)))
 263 #define POSN_SET_POSN(posn,x) (XSETCAR (XCDR (posn), (x)))
 264 #define POSN_WINDOW_POSN(posn) (XCAR (XCDR (XCDR (posn))))
 265 #define POSN_TIMESTAMP(posn) (XCAR (XCDR (XCDR (XCDR (posn)))))
 266 #define POSN_SCROLLBAR_PART(posn)       (Fnth (make_number (4), (posn)))
 267
 268 /* A cons (STRING . STRING-CHARPOS), or nil in mouse-click events.
 269    It's a cons if the click is over a string in the mode line.  */
 270
 271 #define POSN_STRING(posn) (Fnth (make_number (4), (posn)))
 272
 273 /* If POSN_STRING is nil, event refers to buffer location.  */
 274
 275 #define POSN_INBUFFER_P(posn) (NILP (POSN_STRING (posn)))
 276 #define POSN_BUFFER_POSN(posn) (Fnth (make_number (5), (posn)))
 277
 278 /* Some of the event heads.  */
 279 extern Lisp_Object Qswitch_frame;
 280
 281 /* Properties on event heads.  */
 282 extern Lisp_Object Qevent_kind, Qevent_symbol_elements;
 283
 284 /* Getting an unmodified version of an event head.  */
 285 #define EVENT_HEAD_UNMODIFIED(event_head) \
 286   (Fcar (Fget ((event_head), Qevent_symbol_elements)))
 287
 288 /* The values of Qevent_kind properties.  */
 289 extern Lisp_Object Qfunction_key, Qmouse_click, Qmouse_movement;
 290 extern Lisp_Object Qscroll_bar_movement;
 291
 292 /* Getting the kind of an event head.  */
 293 #define EVENT_HEAD_KIND(event_head) \
 294   (Fget ((event_head), Qevent_kind))
 295
 296 /* Symbols to use for non-text mouse positions.  */
 297 extern Lisp_Object Qmode_line, Qvertical_line, Qheader_line;
 298
 299 /* Forward declaration for prototypes.  */
 300 struct input_event;
 301
 302 extern Lisp_Object parse_modifiers P_ ((Lisp_Object));
 303 extern Lisp_Object reorder_modifiers P_ ((Lisp_Object));
 304 extern Lisp_Object read_char P_ ((int, int, Lisp_Object *, Lisp_Object, int *));
 305 /* User-supplied string to translate input characters through.  */
 306 extern Lisp_Object Vkeyboard_translate_table;
 307
 308 /* Parent keymap of terminal-local function-key-map instances.  */
 309 extern Lisp_Object Vfunction_key_map;
 310
 311 /* Parent keymap of terminal-local key-translation-map instances.  */
 312 extern Lisp_Object Vkey_translation_map;
 313
 314
 315 extern int parse_menu_item P_ ((Lisp_Object, int, int));
 316
 317 extern void echo_now P_ ((void));
 318 extern void init_kboard P_ ((KBOARD *));
 319 extern void delete_kboard P_ ((KBOARD *));
 320 extern void single_kboard_state P_ ((void));
 321 extern void not_single_kboard_state P_ ((KBOARD *));
 322 extern void push_device_kboard P_ ((struct device *));
 323 extern void push_frame_kboard P_ ((struct frame *));
 324 extern void pop_frame_kboard P_ ((void));
 325 extern void record_asynch_buffer_change P_ ((void));
 326 extern SIGTYPE input_poll_signal P_ ((int));
 327 extern void start_polling P_ ((void));
 328 extern void stop_polling P_ ((void));
 329 extern void set_poll_suppress_count P_ ((int));
 330 extern void gobble_input P_ ((int));
 331 extern int input_polling_used P_ ((void));
 332 extern void clear_input_pending P_ ((void));
 333 extern int requeued_events_pending_p P_ ((void));
 334 extern void bind_polling_period P_ ((int));
 335 extern void stuff_buffered_input P_ ((Lisp_Object));
 336 extern void clear_waiting_for_input P_ ((void));
 337 extern void swallow_events P_ ((int));
 338 extern int help_char_p P_ ((Lisp_Object));
 339 extern void quit_throw_to_read_char P_ ((void)) NO_RETURN;
 340 extern void cmd_error_internal P_ ((Lisp_Object, char *));
 341 extern int lucid_event_type_list_p P_ ((Lisp_Object));
 342 extern void kbd_buffer_store_event P_ ((struct input_event *));
 343 extern void kbd_buffer_store_event_hold P_ ((struct input_event *,
 344                                              struct input_event *));
 345 extern void kbd_buffer_unget_event P_ ((struct input_event *));
 346 #ifdef POLL_FOR_INPUT
 347 extern void poll_for_input_1 P_ ((void));
 348 #endif
 349 extern void show_help_echo P_ ((Lisp_Object, Lisp_Object, Lisp_Object,
 350                                 Lisp_Object, int));
 351 extern void gen_help_event P_ ((Lisp_Object, Lisp_Object, Lisp_Object,
 352                                Lisp_Object, int));
 353 extern void kbd_buffer_store_help_event P_ ((Lisp_Object, Lisp_Object));
 354 extern Lisp_Object menu_item_eval_property P_ ((Lisp_Object));
 355 extern int  kbd_buffer_events_waiting P_ ((int));
 356
 357 extern int tty_read_avail_input P_ ((struct device *, int,
 358                                      struct input_event *));
 359
 360 /* arch-tag: 769cbade-1ba9-4950-b886-db265b061aa3
 361    (do not change this comment) */