src/keyboard.h

   1 /* Declarations useful when processing input.
   2    Copyright (C) 1985, 1986, 1987, 1993, 2001, 2002, 2003, 2004,
   3                  2005, 2006, 2007, 2008  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 3 of the License, or
  10 (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "systime.h"            /* for EMACS_TIME */
  21
  22 /* Length of echobuf field in each KBOARD.  */
  23
  24 /* Each KBOARD represents one logical input stream from which Emacs
  25    gets input.  If we are using ordinary terminals, it has one KBOARD
  26    object for each terminal device.
  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 other commands.  */
  82     Lisp_Object Vreal_last_command;
  83
  84     /* User-supplied table to translate input characters through.  */
  85     Lisp_Object Vkeyboard_translate_table;
  86
  87     /* Last command that may be repeated by `repeat'.  */
  88     Lisp_Object Vlast_repeatable_command;
  89
  90     /* The prefix argument for the next command, in raw form.  */
  91     Lisp_Object Vprefix_arg;
  92
  93     /* Saved prefix argument for the last command, in raw form.  */
  94     Lisp_Object Vlast_prefix_arg;
  95
  96     /* Unread events specific to this kboard.  */
  97     Lisp_Object kbd_queue;
  98
  99     /* Non-nil while a kbd macro is being defined.  */
 100     Lisp_Object defining_kbd_macro;
 101
 102     /* The start of storage for the current keyboard macro.  */
 103     Lisp_Object *kbd_macro_buffer;
 104
 105     /* Where to store the next keystroke of the macro.  */
 106     Lisp_Object *kbd_macro_ptr;
 107
 108     /* The finalized section of the macro starts at kbd_macro_buffer and
 109        ends before this.  This is not the same as kbd_macro_ptr, because
 110        we advance this to kbd_macro_ptr when a key's command is complete.
 111        This way, the keystrokes for "end-kbd-macro" are not included in the
 112        macro.  This also allows us to throw away the events added to the
 113        macro by the last command: all the events between kbd_macro_end and
 114        kbd_macro_ptr belong to the last command; see
 115        cancel-kbd-macro-events.  */
 116     Lisp_Object *kbd_macro_end;
 117
 118     /* Allocated size of kbd_macro_buffer.  */
 119     int kbd_macro_bufsize;
 120
 121     /* Last anonymous kbd macro defined.  */
 122     Lisp_Object Vlast_kbd_macro;
 123
 124     /* Alist of system-specific X windows key symbols.  */
 125     Lisp_Object Vsystem_key_alist;
 126
 127     /* Cache for modify_event_symbol.  */
 128     Lisp_Object system_key_syms;
 129
 130     /* The kind of display: x, w32, ...  */
 131     Lisp_Object Vwindow_system;
 132
 133     /* Keymap mapping keys to alternative preferred forms.
 134        See the DEFVAR for more documentation.  */
 135     Lisp_Object Vlocal_function_key_map;
 136
 137     /* Keymap mapping ASCII function key sequences onto their preferred
 138        forms.  Initialized by the terminal-specific lisp files.  See the
 139        DEFVAR for more documentation.  */
 140     Lisp_Object Vinput_decode_map;
 141
 142     /* Minibufferless frames on this display use this frame's minibuffer.  */
 143     Lisp_Object Vdefault_minibuffer_frame;
 144
 145     /* Number of displays using this KBOARD.  Normally 1, but can be
 146        larger when you have multiple screens on a single X display.  */
 147     int reference_count;
 148
 149     /* The text we're echoing in the modeline - partial key sequences,
 150        usually.  This is nil when not echoing.  */
 151     Lisp_Object echo_string;
 152
 153     /* This flag indicates that events were put into kbd_queue
 154        while Emacs was running for some other KBOARD.
 155        The flag means that, when Emacs goes into the any-kboard state again,
 156        it should check this KBOARD to see if there is a complete command
 157        waiting.
 158
 159        Note that the kbd_queue field can be non-nil even when
 160        kbd_queue_has_data is 0.  When we push back an incomplete
 161        command, then this flag is 0, meaning we don't want to try
 162        reading from this KBOARD again until more input arrives.  */
 163     char kbd_queue_has_data;
 164
 165     /* Nonzero means echo each character as typed.  */
 166     char immediate_echo;
 167
 168     /* If we have echoed a prompt string specified by the user,
 169        this is its length in characters.  Otherwise this is -1.  */
 170     char echo_after_prompt;
 171   };
 172
 173 #ifdef MULTI_KBOARD
 174 /* Temporarily used before a frame has been opened. */
 175 extern KBOARD *initial_kboard;
 176
 177 /* In the single-kboard state, this is the kboard
 178    from which input is accepted.
 179
 180    In the any-kboard state, this is the kboard from which we are
 181    right now considering input.  We can consider input from another
 182    kboard, but doing so requires throwing to wrong_kboard_jmpbuf.  */
 183 extern KBOARD *current_kboard;
 184
 185 /* A list of all kboard objects, linked through next_kboard.  */
 186 extern KBOARD *all_kboards;
 187
 188 /* Nonzero in the single-kboard state, 0 in the any-kboard state.  */
 189 extern int single_kboard;
 190 #else
 191 extern KBOARD the_only_kboard;
 192 #define current_kboard (&the_only_kboard)
 193 #define all_kboards (&the_only_kboard)
 194 #define single_kboard 1
 195 #endif
 196 \f
 197 extern Lisp_Object Vlucid_menu_bar_dirty_flag;
 198 extern Lisp_Object Qrecompute_lucid_menubar, Qactivate_menubar_hook;
 199
 200 /* Total number of times read_char has returned.  */
 201 extern int num_input_events;
 202
 203 /* Total number of times read_char has returned, outside of macros.  */
 204 extern EMACS_INT num_nonmacro_input_events;
 205
 206 /* Nonzero means polling for input is temporarily suppressed.  */
 207 extern int poll_suppress_count;
 208
 209 /* Vector holding the key sequence that invoked the current command.
 210    It is reused for each command, and it may be longer than the current
 211    sequence; this_command_key_count indicates how many elements
 212    actually mean something.  */
 213 extern Lisp_Object this_command_keys;
 214 extern int this_command_key_count;
 215
 216 /* The frame in which the last input event occurred, or Qmacro if the
 217    last event came from a macro.  We use this to determine when to
 218    generate switch-frame events.  This may be cleared by functions
 219    like Fselect_frame, to make sure that a switch-frame event is
 220    generated by the next character.  */
 221 extern Lisp_Object internal_last_event_frame;
 222 \f
 223 /* This holds a Lisp vector that holds the properties of a single
 224    menu item while decoding it in parse_menu_item.
 225    Using a Lisp vector to hold this information while we decode it
 226    takes care of protecting all the data from GC.  */
 227 extern Lisp_Object item_properties;
 228
 229 /* This describes the elements of item_properties.
 230    The first element is not a property, it is a pointer to the item properties
 231    that is saved for GC protection. */
 232 #define ITEM_PROPERTY_ITEM 0
 233 /* The item string.  */
 234 #define ITEM_PROPERTY_NAME 1
 235 /* Start of initialize to nil */
 236 /* The binding: nil, a command or a keymap.  */
 237 #define ITEM_PROPERTY_DEF 2
 238 /* The keymap if the binding is a keymap, otherwise nil.  */
 239 #define ITEM_PROPERTY_MAP 3
 240 /* Nil, :radio or :toggle.  */
 241 #define ITEM_PROPERTY_TYPE 4
 242 /* Nil or a string describing an equivalent key binding.  */
 243 #define ITEM_PROPERTY_KEYEQ 5
 244 /* Not nil if a selected toggle box or radio button, otherwise nil.  */
 245 #define ITEM_PROPERTY_SELECTED 6
 246 /* Place for a help string. Not yet used.  */
 247 #define ITEM_PROPERTY_HELP 7
 248 /* Start of initialize to t */
 249 /* Last property. */
 250 /* Not nil if item is enabled.  */
 251 #define ITEM_PROPERTY_ENABLE 8
 252 \f
 253 /* Macros for dealing with lispy events.  */
 254
 255 /* True if EVENT has data fields describing it (i.e. a mouse click).  */
 256 #define EVENT_HAS_PARAMETERS(event) (CONSP (event))
 257
 258 /* Extract the head from an event.
 259    This works on composite and simple events.  */
 260 #define EVENT_HEAD(event) \
 261   (EVENT_HAS_PARAMETERS (event) ? XCAR (event) : (event))
 262
 263 /* Extract the starting and ending positions from a composite event.  */
 264 #define EVENT_START(event) (XCAR (XCDR (event)))
 265 #define EVENT_END(event) (XCAR (XCDR (XCDR (event))))
 266
 267 /* Extract the click count from a multi-click event.  */
 268 #define EVENT_CLICK_COUNT(event) (Fnth (make_number (2), (event)))
 269
 270 /* Extract the fields of a position.  */
 271 #define POSN_WINDOW(posn) (XCAR (posn))
 272 #define POSN_POSN(posn) (XCAR (XCDR (posn)))
 273 #define POSN_SET_POSN(posn,x) (XSETCAR (XCDR (posn), (x)))
 274 #define POSN_WINDOW_POSN(posn) (XCAR (XCDR (XCDR (posn))))
 275 #define POSN_TIMESTAMP(posn) (XCAR (XCDR (XCDR (XCDR (posn)))))
 276 #define POSN_SCROLLBAR_PART(posn)       (Fnth (make_number (4), (posn)))
 277
 278 /* A cons (STRING . STRING-CHARPOS), or nil in mouse-click events.
 279    It's a cons if the click is over a string in the mode line.  */
 280
 281 #define POSN_STRING(posn) (Fnth (make_number (4), (posn)))
 282
 283 /* If POSN_STRING is nil, event refers to buffer location.  */
 284
 285 #define POSN_INBUFFER_P(posn) (NILP (POSN_STRING (posn)))
 286 #define POSN_BUFFER_POSN(posn) (Fnth (make_number (5), (posn)))
 287
 288 /* Some of the event heads.  */
 289 extern Lisp_Object Qswitch_frame;
 290
 291 /* Properties on event heads.  */
 292 extern Lisp_Object Qevent_kind, Qevent_symbol_elements;
 293
 294 /* Getting an unmodified version of an event head.  */
 295 #define EVENT_HEAD_UNMODIFIED(event_head) \
 296   (Fcar (Fget ((event_head), Qevent_symbol_elements)))
 297
 298 /* The values of Qevent_kind properties.  */
 299 extern Lisp_Object Qfunction_key, Qmouse_click, Qmouse_movement;
 300 extern Lisp_Object Qscroll_bar_movement;
 301
 302 /* Getting the kind of an event head.  */
 303 #define EVENT_HEAD_KIND(event_head) \
 304   (Fget ((event_head), Qevent_kind))
 305
 306 /* Symbols to use for non-text mouse positions.  */
 307 extern Lisp_Object Qmode_line, Qvertical_line, Qheader_line;
 308
 309 /* Forward declaration for prototypes.  */
 310 struct input_event;
 311
 312 extern Lisp_Object parse_modifiers P_ ((Lisp_Object));
 313 extern Lisp_Object reorder_modifiers P_ ((Lisp_Object));
 314 extern Lisp_Object read_char P_ ((int, int, Lisp_Object *, Lisp_Object,
 315                                   int *, EMACS_TIME *));
 316
 317
 318 /* Parent keymap of terminal-local function-key-map instances.  */
 319 extern Lisp_Object Vfunction_key_map;
 320
 321 /* Keymap of key translations that can override keymaps.  */
 322 extern Lisp_Object Vkey_translation_map;
 323
 324 extern int parse_menu_item P_ ((Lisp_Object, int, int));
 325
 326 extern void echo_now P_ ((void));
 327 extern void init_kboard P_ ((KBOARD *));
 328 extern void delete_kboard P_ ((KBOARD *));
 329 extern void not_single_kboard_state P_ ((KBOARD *));
 330 extern void push_kboard P_ ((struct kboard *));
 331 extern void push_frame_kboard P_ ((struct frame *));
 332 extern void pop_kboard P_ ((void));
 333 extern void temporarily_switch_to_single_kboard P_ ((struct frame *));
 334 extern void record_asynch_buffer_change P_ ((void));
 335 extern SIGTYPE input_poll_signal P_ ((int));
 336 extern void start_polling P_ ((void));
 337 extern void stop_polling P_ ((void));
 338 extern void set_poll_suppress_count P_ ((int));
 339 extern void gobble_input P_ ((int));
 340 extern int input_polling_used P_ ((void));
 341 extern void clear_input_pending P_ ((void));
 342 extern int requeued_events_pending_p P_ ((void));
 343 extern void bind_polling_period P_ ((int));
 344 extern void stuff_buffered_input P_ ((Lisp_Object));
 345 extern void clear_waiting_for_input P_ ((void));
 346 extern void swallow_events P_ ((int));
 347 extern int help_char_p P_ ((Lisp_Object));
 348 extern void quit_throw_to_read_char P_ ((void)) NO_RETURN;
 349 extern void cmd_error_internal P_ ((Lisp_Object, char *));
 350 extern int lucid_event_type_list_p P_ ((Lisp_Object));
 351 extern void kbd_buffer_store_event P_ ((struct input_event *));
 352 extern void kbd_buffer_store_event_hold P_ ((struct input_event *,
 353                                              struct input_event *));
 354 extern void kbd_buffer_unget_event P_ ((struct input_event *));
 355 #ifdef POLL_FOR_INPUT
 356 extern void poll_for_input_1 P_ ((void));
 357 #endif
 358 extern void show_help_echo P_ ((Lisp_Object, Lisp_Object, Lisp_Object,
 359                                 Lisp_Object, int));
 360 extern void gen_help_event P_ ((Lisp_Object, Lisp_Object, Lisp_Object,
 361                                Lisp_Object, int));
 362 extern void kbd_buffer_store_help_event P_ ((Lisp_Object, Lisp_Object));
 363 extern Lisp_Object menu_item_eval_property P_ ((Lisp_Object));
 364 extern int  kbd_buffer_events_waiting P_ ((int));
 365 extern void add_user_signals P_ ((int, const char *));
 366
 367 extern int tty_read_avail_input P_ ((struct terminal *, int,
 368                                      struct input_event *));
 369
 370 /* arch-tag: 769cbade-1ba9-4950-b886-db265b061aa3
 371    (do not change this comment) */