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 #include "systime.h"            /* for EMACS_TIME */
  23
  24 /* Length of echobuf field in each KBOARD.  */
  25
  26 /* Each KBOARD represents one logical input stream from which Emacs gets input.
  27    If we are using an ordinary terminal, it has one KBOARD object.
  28    Usually each X display screen has its own KBOARD,
  29    but when two of them are on the same X server,
  30    we assume they share a keyboard and give them one KBOARD in common.
  31
  32    Some Lisp variables are per-kboard; they are stored in the KBOARD structure
  33    and accessed indirectly via a Lisp_Misc_Kboard_Objfwd object.
  34
  35    So that definition of keyboard macros, and reading of prefix arguments,
  36    can happen in parallel on various KBOARDs at once,
  37    the state information for those activities is stored in the KBOARD.
  38
  39    Emacs has two states for reading input:
  40
  41    ** Any kboard.  Emacs can accept input from any KBOARD,
  42    and as soon as any of them provides a complete command, Emacs can run it.
  43
  44    ** Single kboard.  Then Emacs is running a command for one KBOARD
  45    and can only read input from that KBOARD.
  46
  47    All input, from all KBOARDs, goes together in a single event queue
  48    at interrupt level.  read_char sees the events sequentially,
  49    but deals with them in accord with the current input state.
  50
  51    In the any-kboard state, read_key_sequence processes input from any KBOARD
  52    immediately.  When a new event comes in from a particular KBOARD,
  53    read_key_sequence switches to that KBOARD.  As a result,
  54    as soon as a complete key arrives from some KBOARD or other,
  55    Emacs starts executing that key's binding.  It switches to the
  56    single-kboard state for the execution of that command,
  57    so that that command can get input only from its own KBOARD.
  58
  59    While in the single-kboard state, read_char can consider input only
  60    from the current KBOARD.  If events come from other KBOARDs, they
  61    are put aside for later in the KBOARDs' kbd_queue lists.
  62    The flag kbd_queue_has_data in a KBOARD is 1 if this has happened.
  63    When Emacs goes back to the any-kboard state, it looks at all the KBOARDs
  64    to find those; and it tries processing their input right away.  */
  65
  66 typedef struct kboard KBOARD;
  67 struct kboard
  68   {
  69     KBOARD *next_kboard;
  70
  71     /* If non-nil, a keymap that overrides all others but applies only to
  72        this KBOARD.  Lisp code that uses this instead of calling read-char
  73        can effectively wait for input in the any-kboard state, and hence
  74        avoid blocking out the other KBOARDs.  See universal-argument in
  75        lisp/simple.el for an example.  */
  76     Lisp_Object Voverriding_terminal_local_map;
  77
  78     /* Last command executed by the editor command loop, not counting
  79        commands that set the prefix argument.  */
  80     Lisp_Object Vlast_command;
  81
  82     /* Normally same as last-command, but never modified by
  83        other commands.  */
  84     Lisp_Object Vreal_last_command;
  85
  86     /* The prefix argument for the next command, in raw form.  */
  87     Lisp_Object Vprefix_arg;
  88
  89     /* Saved prefix argument for the last command, in raw form.  */
  90     Lisp_Object Vlast_prefix_arg;
  91
  92     /* Unread events specific to this kboard.  */
  93     Lisp_Object kbd_queue;
  94
  95     /* Non-nil while a kbd macro is being defined.  */
  96     Lisp_Object defining_kbd_macro;
  97
  98     /* The start of storage for the current keyboard macro.  */
  99     Lisp_Object *kbd_macro_buffer;
 100
 101     /* Where to store the next keystroke of the macro.  */
 102     Lisp_Object *kbd_macro_ptr;
 103
 104     /* The finalized section of the macro starts at kbd_macro_buffer and
 105        ends before this.  This is not the same as kbd_macro_ptr, because
 106        we advance this to kbd_macro_ptr when a key's command is complete.
 107        This way, the keystrokes for "end-kbd-macro" are not included in the
 108        macro.  This also allows us to throw away the events added to the
 109        macro by the last command: all the events between kbd_macro_end and
 110        kbd_macro_ptr belong to the last command; see
 111        cancel-kbd-macro-events.  */
 112     Lisp_Object *kbd_macro_end;
 113
 114     /* Allocated size of kbd_macro_buffer.  */
 115     int kbd_macro_bufsize;
 116
 117     /* Last anonymous kbd macro defined.  */
 118     Lisp_Object Vlast_kbd_macro;
 119
 120     /* Alist of system-specific X windows key symbols.  */
 121     Lisp_Object Vsystem_key_alist;
 122
 123     /* Cache for modify_event_symbol.  */
 124     Lisp_Object system_key_syms;
 125
 126     /* Minibufferless frames on this display use this frame's minibuffer.  */
 127     Lisp_Object Vdefault_minibuffer_frame;
 128
 129     /* Number of displays using this KBOARD.  Normally 1, but can be
 130        larger when you have multiple screens on a single X display.  */
 131     int reference_count;
 132
 133     /* The text we're echoing in the modeline - partial key sequences,
 134        usually.  This is nil when not echoing.  */
 135     Lisp_Object echo_string;
 136
 137     /* This flag indicates that events were put into kbd_queue
 138        while Emacs was running for some other KBOARD.
 139        The flag means that, when Emacs goes into the any-kboard state again,
 140        it should check this KBOARD to see if there is a complete command
 141        waiting.
 142
 143        Note that the kbd_queue field can be non-nil even when
 144        kbd_queue_has_data is 0.  When we push back an incomplete
 145        command, then this flag is 0, meaning we don't want to try
 146        reading from this KBOARD again until more input arrives.  */
 147     char kbd_queue_has_data;
 148
 149     /* Nonzero means echo each character as typed.  */
 150     char immediate_echo;
 151
 152     /* If we have echoed a prompt string specified by the user,
 153        this is its length in characters.  Otherwise this is -1.  */
 154     char echo_after_prompt;
 155   };
 156
 157 #ifdef MULTI_KBOARD
 158 /* Temporarily used before a frame has been opened, and for termcap frames */
 159 extern KBOARD *initial_kboard;
 160
 161 /* In the single-kboard state, this is the kboard
 162    from which input is accepted.
 163
 164    In the any-kboard state, this is the kboard from which we are
 165    right now considering input.  We can consider input from another
 166    kboard, but doing so requires throwing to wrong_kboard_jmpbuf.  */
 167 extern KBOARD *current_kboard;
 168
 169 /* A list of all kboard objects, linked through next_kboard.  */
 170 extern KBOARD *all_kboards;
 171
 172 /* Nonzero in the single-kboard state, 0 in the any-kboard state.  */
 173 extern int single_kboard;
 174 #else
 175 extern KBOARD the_only_kboard;
 176 #define current_kboard (&the_only_kboard)
 177 #define all_kboards (&the_only_kboard)
 178 #define single_kboard 1
 179 #endif
 180 \f
 181 extern Lisp_Object Vlucid_menu_bar_dirty_flag;
 182 extern Lisp_Object Qrecompute_lucid_menubar, Qactivate_menubar_hook;
 183
 184 /* Total number of times read_char has returned.  */
 185 extern int num_input_events;
 186
 187 /* Total number of times read_char has returned, outside of macros.  */
 188 extern EMACS_INT num_nonmacro_input_events;
 189
 190 /* Nonzero means polling for input is temporarily suppressed.  */
 191 extern int poll_suppress_count;
 192
 193 /* Keymap mapping ASCII function key sequences onto their preferred forms.
 194    Initialized by the terminal-specific lisp files.  */
 195 extern Lisp_Object Vfunction_key_map;
 196
 197 /* Vector holding the key sequence that invoked the current command.
 198    It is reused for each command, and it may be longer than the current
 199    sequence; this_command_key_count indicates how many elements
 200    actually mean something.  */
 201 extern Lisp_Object this_command_keys;
 202 extern int this_command_key_count;
 203
 204 /* The frame in which the last input event occurred, or Qmacro if the
 205    last event came from a macro.  We use this to determine when to
 206    generate switch-frame events.  This may be cleared by functions
 207    like Fselect_frame, to make sure that a switch-frame event is
 208    generated by the next character.  */
 209 extern Lisp_Object internal_last_event_frame;
 210 \f
 211 /* This holds a Lisp vector that holds the properties of a single
 212    menu item while decoding it in parse_menu_item.
 213    Using a Lisp vector to hold this information while we decode it
 214    takes care of protecting all the data from GC.  */
 215 extern Lisp_Object item_properties;
 216
 217 /* This describes the elements of item_properties.
 218    The first element is not a property, it is a pointer to the item properties
 219    that is saved for GC protection. */
 220 #define ITEM_PROPERTY_ITEM 0
 221 /* The item string.  */
 222 #define ITEM_PROPERTY_NAME 1
 223 /* Start of initialize to nil */
 224 /* The binding: nil, a command or a keymap.  */
 225 #define ITEM_PROPERTY_DEF 2
 226 /* The keymap if the binding is a keymap, otherwise nil.  */
 227 #define ITEM_PROPERTY_MAP 3
 228 /* Nil, :radio or :toggle.  */
 229 #define ITEM_PROPERTY_TYPE 4
 230 /* Nil or a string describing an equivalent key binding.  */
 231 #define ITEM_PROPERTY_KEYEQ 5
 232 /* Not nil if a selected toggle box or radio button, otherwise nil.  */
 233 #define ITEM_PROPERTY_SELECTED 6
 234 /* Place for a help string. Not yet used.  */
 235 #define ITEM_PROPERTY_HELP 7
 236 /* Start of initialize to t */
 237 /* Last property. */
 238 /* Not nil if item is enabled.  */
 239 #define ITEM_PROPERTY_ENABLE 8
 240 \f
 241 /* Macros for dealing with lispy events.  */
 242
 243 /* True iff EVENT has data fields describing it (i.e. a mouse click).  */
 244 #define EVENT_HAS_PARAMETERS(event) (CONSP (event))
 245
 246 /* Extract the head from an event.
 247    This works on composite and simple events.  */
 248 #define EVENT_HEAD(event) \
 249   (EVENT_HAS_PARAMETERS (event) ? XCAR (event) : (event))
 250
 251 /* Extract the starting and ending positions from a composite event.  */
 252 #define EVENT_START(event) (XCAR (XCDR (event)))
 253 #define EVENT_END(event) (XCAR (XCDR (XCDR (event))))
 254
 255 /* Extract the click count from a multi-click event.  */
 256 #define EVENT_CLICK_COUNT(event) (Fnth (make_number (2), (event)))
 257
 258 /* Extract the fields of a position.  */
 259 #define POSN_WINDOW(posn) (XCAR (posn))
 260 #define POSN_POSN(posn) (XCAR (XCDR (posn)))
 261 #define POSN_SET_POSN(posn,x) (XSETCAR (XCDR (posn), (x)))
 262 #define POSN_WINDOW_POSN(posn) (XCAR (XCDR (XCDR (posn))))
 263 #define POSN_TIMESTAMP(posn) (XCAR (XCDR (XCDR (XCDR (posn)))))
 264 #define POSN_SCROLLBAR_PART(posn)       (Fnth (make_number (4), (posn)))
 265
 266 /* A cons (STRING . STRING-CHARPOS), or nil in mouse-click events.
 267    It's a cons if the click is over a string in the mode line.  */
 268
 269 #define POSN_STRING(posn) (Fnth (make_number (4), (posn)))
 270
 271 /* If POSN_STRING is nil, event refers to buffer location.  */
 272
 273 #define POSN_INBUFFER_P(posn) (NILP (POSN_STRING (posn)))
 274 #define POSN_BUFFER_POSN(posn) (Fnth (make_number (5), (posn)))
 275
 276 /* Some of the event heads.  */
 277 extern Lisp_Object Qswitch_frame;
 278
 279 /* Properties on event heads.  */
 280 extern Lisp_Object Qevent_kind, Qevent_symbol_elements;
 281
 282 /* Getting an unmodified version of an event head.  */
 283 #define EVENT_HEAD_UNMODIFIED(event_head) \
 284   (Fcar (Fget ((event_head), Qevent_symbol_elements)))
 285
 286 /* The values of Qevent_kind properties.  */
 287 extern Lisp_Object Qfunction_key, Qmouse_click, Qmouse_movement;
 288 extern Lisp_Object Qscroll_bar_movement;
 289
 290 /* Getting the kind of an event head.  */
 291 #define EVENT_HEAD_KIND(event_head) \
 292   (Fget ((event_head), Qevent_kind))
 293
 294 /* Symbols to use for non-text mouse positions.  */
 295 extern Lisp_Object Qmode_line, Qvertical_line, Qheader_line;
 296
 297 /* Forward declaration for prototypes.  */
 298 struct input_event;
 299
 300 extern Lisp_Object parse_modifiers P_ ((Lisp_Object));
 301 extern Lisp_Object reorder_modifiers P_ ((Lisp_Object));
 302 extern Lisp_Object read_char P_ ((int, int, Lisp_Object *, Lisp_Object,
 303                                   int *, EMACS_TIME *));
 304 /* User-supplied string to translate input characters through.  */
 305 extern Lisp_Object Vkeyboard_translate_table;
 306
 307 extern int parse_menu_item P_ ((Lisp_Object, int, int));
 308
 309 extern void echo_now P_ ((void));
 310 extern void init_kboard P_ ((KBOARD *));
 311 extern void delete_kboard P_ ((KBOARD *));
 312 extern void single_kboard_state P_ ((void));
 313 extern void not_single_kboard_state P_ ((KBOARD *));
 314 extern void push_frame_kboard P_ ((struct frame *));
 315 extern void pop_frame_kboard P_ ((void));
 316 extern void record_asynch_buffer_change P_ ((void));
 317 extern SIGTYPE input_poll_signal P_ ((int));
 318 extern void start_polling P_ ((void));
 319 extern void stop_polling P_ ((void));
 320 extern void set_poll_suppress_count P_ ((int));
 321 extern void gobble_input P_ ((int));
 322 extern int input_polling_used P_ ((void));
 323 extern void clear_input_pending P_ ((void));
 324 extern int requeued_events_pending_p P_ ((void));
 325 extern void bind_polling_period P_ ((int));
 326 extern void stuff_buffered_input P_ ((Lisp_Object));
 327 extern void clear_waiting_for_input P_ ((void));
 328 extern void swallow_events P_ ((int));
 329 extern int help_char_p P_ ((Lisp_Object));
 330 extern void quit_throw_to_read_char P_ ((void)) NO_RETURN;
 331 extern void cmd_error_internal P_ ((Lisp_Object, char *));
 332 extern int lucid_event_type_list_p P_ ((Lisp_Object));
 333 extern void kbd_buffer_store_event P_ ((struct input_event *));
 334 extern void kbd_buffer_store_event_hold P_ ((struct input_event *,
 335                                              struct input_event *));
 336 extern void kbd_buffer_unget_event P_ ((struct input_event *));
 337 #ifdef POLL_FOR_INPUT
 338 extern void poll_for_input_1 P_ ((void));
 339 #endif
 340 extern void show_help_echo P_ ((Lisp_Object, Lisp_Object, Lisp_Object,
 341                                 Lisp_Object, int));
 342 extern void gen_help_event P_ ((Lisp_Object, Lisp_Object, Lisp_Object,
 343                                Lisp_Object, int));
 344 extern void kbd_buffer_store_help_event P_ ((Lisp_Object, Lisp_Object));
 345 extern Lisp_Object menu_item_eval_property P_ ((Lisp_Object));
 346 extern int  kbd_buffer_events_waiting P_ ((int));
 347 extern void add_user_signals P_ ((int, const char *));
 348
 349 /* arch-tag: 769cbade-1ba9-4950-b886-db265b061aa3
 350    (do not change this comment) */