src/keyboard.h

   1 /* Declarations useful when processing input.
   2    Copyright (C) 1985, 1986, 1987, 1993, 2002, 2003, 2004,
   3                  2005, 2006 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 an ordinary terminal, it has one KBOARD object.
  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     /* Minibufferless frames on this display use this frame's minibuffer.  */
 125     Lisp_Object Vdefault_minibuffer_frame;
 126
 127     /* Number of displays using this KBOARD.  Normally 1, but can be
 128        larger when you have multiple screens on a single X display.  */
 129     int reference_count;
 130
 131     /* The text we're echoing in the modeline - partial key sequences,
 132        usually.  This is nil when not echoing.  */
 133     Lisp_Object echo_string;
 134
 135     /* This flag indicates that events were put into kbd_queue
 136        while Emacs was running for some other KBOARD.
 137        The flag means that, when Emacs goes into the any-kboard state again,
 138        it should check this KBOARD to see if there is a complete command
 139        waiting.
 140
 141        Note that the kbd_queue field can be non-nil even when
 142        kbd_queue_has_data is 0.  When we push back an incomplete
 143        command, then this flag is 0, meaning we don't want to try
 144        reading from this KBOARD again until more input arrives.  */
 145     char kbd_queue_has_data;
 146
 147     /* Nonzero means echo each character as typed.  */
 148     char immediate_echo;
 149
 150     /* If we have echoed a prompt string specified by the user,
 151        this is its length in characters.  Otherwise this is -1.  */
 152     char echo_after_prompt;
 153   };
 154
 155 #ifdef MULTI_KBOARD
 156 /* Temporarily used before a frame has been opened, and for termcap frames */
 157 extern KBOARD *initial_kboard;
 158
 159 /* In the single-kboard state, this is the kboard
 160    from which input is accepted.
 161
 162    In the any-kboard state, this is the kboard from which we are
 163    right now considering input.  We can consider input from another
 164    kboard, but doing so requires throwing to wrong_kboard_jmpbuf.  */
 165 extern KBOARD *current_kboard;
 166
 167 /* A list of all kboard objects, linked through next_kboard.  */
 168 extern KBOARD *all_kboards;
 169
 170 /* Nonzero in the single-kboard state, 0 in the any-kboard state.  */
 171 extern int single_kboard;
 172 #else
 173 extern KBOARD the_only_kboard;
 174 #define current_kboard (&the_only_kboard)
 175 #define all_kboards (&the_only_kboard)
 176 #define single_kboard 1
 177 #endif
 178 \f
 179 extern Lisp_Object Vlucid_menu_bar_dirty_flag;
 180 extern Lisp_Object Qrecompute_lucid_menubar, Qactivate_menubar_hook;
 181
 182 /* Total number of times read_char has returned.  */
 183 extern int num_input_events;
 184
 185 /* Total number of times read_char has returned, outside of macros.  */
 186 extern EMACS_INT num_nonmacro_input_events;
 187
 188 /* Nonzero means polling for input is temporarily suppressed.  */
 189 extern int poll_suppress_count;
 190
 191 /* Keymap mapping ASCII function key sequences onto their preferred forms.
 192    Initialized by the terminal-specific lisp files.  */
 193 extern Lisp_Object Vfunction_key_map;
 194
 195 /* Vector holding the key sequence that invoked the current command.
 196    It is reused for each command, and it may be longer than the current
 197    sequence; this_command_key_count indicates how many elements
 198    actually mean something.  */
 199 extern Lisp_Object this_command_keys;
 200 extern int this_command_key_count;
 201
 202 /* The frame in which the last input event occurred, or Qmacro if the
 203    last event came from a macro.  We use this to determine when to
 204    generate switch-frame events.  This may be cleared by functions
 205    like Fselect_frame, to make sure that a switch-frame event is
 206    generated by the next character.  */
 207 extern Lisp_Object internal_last_event_frame;
 208 \f
 209 /* This holds a Lisp vector that holds the properties of a single
 210    menu item while decoding it in parse_menu_item.
 211    Using a Lisp vector to hold this information while we decode it
 212    takes care of protecting all the data from GC.  */
 213 extern Lisp_Object item_properties;
 214
 215 /* This describes the elements of item_properties.
 216    The first element is not a property, it is a pointer to the item properties
 217    that is saved for GC protection. */
 218 #define ITEM_PROPERTY_ITEM 0
 219 /* The item string.  */
 220 #define ITEM_PROPERTY_NAME 1
 221 /* Start of initialize to nil */
 222 /* The binding: nil, a command or a keymap.  */
 223 #define ITEM_PROPERTY_DEF 2
 224 /* The keymap if the binding is a keymap, otherwise nil.  */
 225 #define ITEM_PROPERTY_MAP 3
 226 /* Nil, :radio or :toggle.  */
 227 #define ITEM_PROPERTY_TYPE 4
 228 /* Nil or a string describing an equivalent key binding.  */
 229 #define ITEM_PROPERTY_KEYEQ 5
 230 /* Not nil if a selected toggle box or radio button, otherwise nil.  */
 231 #define ITEM_PROPERTY_SELECTED 6
 232 /* Place for a help string. Not yet used.  */
 233 #define ITEM_PROPERTY_HELP 7
 234 /* Start of initialize to t */
 235 /* Last property. */
 236 /* Not nil if item is enabled.  */
 237 #define ITEM_PROPERTY_ENABLE 8
 238 \f
 239 /* Macros for dealing with lispy events.  */
 240
 241 /* True iff EVENT has data fields describing it (i.e. a mouse click).  */
 242 #define EVENT_HAS_PARAMETERS(event) (CONSP (event))
 243
 244 /* Extract the head from an event.
 245    This works on composite and simple events.  */
 246 #define EVENT_HEAD(event) \
 247   (EVENT_HAS_PARAMETERS (event) ? XCAR (event) : (event))
 248
 249 /* Extract the starting and ending positions from a composite event.  */
 250 #define EVENT_START(event) (XCAR (XCDR (event)))
 251 #define EVENT_END(event) (XCAR (XCDR (XCDR (event))))
 252
 253 /* Extract the click count from a multi-click event.  */
 254 #define EVENT_CLICK_COUNT(event) (Fnth (make_number (2), (event)))
 255
 256 /* Extract the fields of a position.  */
 257 #define POSN_WINDOW(posn) (XCAR (posn))
 258 #define POSN_POSN(posn) (XCAR (XCDR (posn)))
 259 #define POSN_SET_POSN(posn,x) (XSETCAR (XCDR (posn), (x)))
 260 #define POSN_WINDOW_POSN(posn) (XCAR (XCDR (XCDR (posn))))
 261 #define POSN_TIMESTAMP(posn) (XCAR (XCDR (XCDR (XCDR (posn)))))
 262 #define POSN_SCROLLBAR_PART(posn)       (Fnth (make_number (4), (posn)))
 263
 264 /* A cons (STRING . STRING-CHARPOS), or nil in mouse-click events.
 265    It's a cons if the click is over a string in the mode line.  */
 266
 267 #define POSN_STRING(posn) (Fnth (make_number (4), (posn)))
 268
 269 /* If POSN_STRING is nil, event refers to buffer location.  */
 270
 271 #define POSN_INBUFFER_P(posn) (NILP (POSN_STRING (posn)))
 272 #define POSN_BUFFER_POSN(posn) (Fnth (make_number (5), (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 extern int parse_menu_item P_ ((Lisp_Object, int, int));
 305
 306 extern void echo_now P_ ((void));
 307 extern void init_kboard P_ ((KBOARD *));
 308 extern void delete_kboard P_ ((KBOARD *));
 309 extern void single_kboard_state P_ ((void));
 310 extern void not_single_kboard_state P_ ((KBOARD *));
 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 int lucid_event_type_list_p P_ ((Lisp_Object));
 330 extern void kbd_buffer_store_event P_ ((struct input_event *));
 331 extern void kbd_buffer_store_event_hold P_ ((struct input_event *,
 332                                              struct input_event *));
 333 extern void kbd_buffer_unget_event P_ ((struct input_event *));
 334 #ifdef POLL_FOR_INPUT
 335 extern void poll_for_input_1 P_ ((void));
 336 #endif
 337 extern void show_help_echo P_ ((Lisp_Object, Lisp_Object, Lisp_Object,
 338                                 Lisp_Object, int));
 339 extern void gen_help_event P_ ((Lisp_Object, Lisp_Object, Lisp_Object,
 340                                Lisp_Object, int));
 341 extern void kbd_buffer_store_help_event P_ ((Lisp_Object, Lisp_Object));
 342 extern Lisp_Object menu_item_eval_property P_ ((Lisp_Object));
 343 extern int  kbd_buffer_events_waiting P_ ((int));
 344
 345 /* arch-tag: 769cbade-1ba9-4950-b886-db265b061aa3
 346    (do not change this comment) */