gnu/dist/texinfo/info/window.h

   1 /*      $NetBSD$        */
   2
   3 /* window.h -- Structure and flags used in manipulating Info windows.
   4    Id: window.h,v 1.3 2004/04/11 17:56:46 karl Exp
   5
   6    This file is part of GNU Info, a program for reading online documentation
   7    stored in Info format.
   8
   9    Copyright (C) 1993, 1997, 2004 Free Software Foundation, Inc.
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 2, or (at your option)
  14    any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program; if not, write to the Free Software
  23    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  24
  25    Written by Brian Fox (bfox@ai.mit.edu). */
  26
  27 #ifndef INFO_WINDOW_H
  28 #define INFO_WINDOW_H
  29
  30 #include "infomap.h"
  31 #include "nodes.h"
  32
  33 /* Smallest number of visible lines in a window.  The actual height is
  34    always one more than this number because each window has a modeline. */
  35 #define WINDOW_MIN_HEIGHT 2
  36
  37 /* Smallest number of screen lines that can be used to fully present a
  38    window.  This number includes the modeline of the window. */
  39 #define WINDOW_MIN_SIZE (WINDOW_MIN_HEIGHT + 1)
  40
  41 /* The exact same elements are used within the WINDOW_STATE structure and a
  42    subsection of the WINDOW structure.  We could define a structure which
  43    contains this elements, and include that structure in each of WINDOW_STATE
  44    and WINDOW.  But that would lead references in the code such as
  45    window->state->node which we would like to avoid.  Instead, we #define the
  46    elements here, and simply include the define in both data structures. Thus,
  47    if you need to change window state information, here is where you would
  48    do it.  NB> The last element does NOT end with a semi-colon. */
  49 #define WINDOW_STATE_DECL \
  50    NODE *node;          /* The node displayed in this window. */ \
  51    int pagetop;         /* LINE_STARTS[PAGETOP] is first line in WINDOW. */ \
  52    long point           /* Offset within NODE of the cursor position. */
  53
  54 /* Structure which defines a window.  Windows are doubly linked, next
  55    and prev. The list of windows is kept on WINDOWS.  The structure member
  56    window->height is the total height of the window.  The position location
  57    (0, window->height + window->first_row) is the first character of this
  58    windows modeline.  The number of lines that can be displayed in a window
  59    is equal to window->height - 1. */
  60 typedef struct window_struct
  61 {
  62   struct window_struct *next;      /* Next window in this chain. */
  63   struct window_struct *prev;      /* Previous window in this chain. */
  64   int width;            /* Width of this window. */
  65   int height;           /* Height of this window. */
  66   int first_row;        /* Offset of the first line in the_screen. */
  67   int goal_column;      /* The column we would like the cursor to appear in. */
  68   Keymap keymap;        /* Keymap used to read commands in this window. */
  69   WINDOW_STATE_DECL;    /* Node, pagetop and point. */
  70   char *modeline;       /* Calculated text of the modeline for this window. */
  71   char **line_starts;   /* Array of printed line starts for this node. */
  72   int line_count;       /* Number of lines appearing in LINE_STARTS. */
  73   int flags;            /* See below for details. */
  74 } WINDOW;
  75
  76 typedef struct {
  77   WINDOW_STATE_DECL;            /* What gets saved. */
  78 } WINDOW_STATE;
  79
  80 /* Structure defining the current state of an incremental search. */
  81 typedef struct {
  82   WINDOW_STATE_DECL;    /* The node, pagetop and point. */
  83   int search_index;     /* Offset of the last char in the search string. */
  84   int direction;        /* The direction that this search is heading in. */
  85   int failing;          /* Whether or not this search failed. */
  86 } SEARCH_STATE;
  87
  88 #define W_UpdateWindow  0x01    /* WINDOW needs updating. */
  89 #define W_WindowIsPerm  0x02    /* This WINDOW is a permanent object. */
  90 #define W_WindowVisible 0x04    /* This WINDOW is currently visible. */
  91 #define W_InhibitMode   0x08    /* This WINDOW has no modeline. */
  92 #define W_NoWrap        0x10    /* Lines do not wrap in this window. */
  93 #define W_InputWindow   0x20    /* Window accepts input. */
  94 #define W_TempWindow    0x40    /* Window is less important. */
  95
  96 extern WINDOW *windows;         /* List of visible Info windows. */
  97 extern WINDOW *active_window;   /* The currently active window. */
  98 extern WINDOW *the_screen;      /* The Info screen is just another window. */
  99 extern WINDOW *the_echo_area;   /* THE_ECHO_AREA is a window in THE_SCREEN. */
 100
 101 /* Global variable control redisplay of scrolled windows.  If non-zero, it
 102    is the desired number of lines to scroll the window in order to make
 103    point visible.  A user might set this to 1 for smooth scrolling.  If
 104    set to zero, the line containing point is centered within the window. */
 105 extern int window_scroll_step;
 106
 107  /* Make the modeline member for WINDOW. */
 108 extern void window_make_modeline (WINDOW *window);
 109
 110 /* Initalize the window system by creating THE_SCREEN and THE_ECHO_AREA.
 111    Create the first window ever, and make it permanent.
 112    You pass WIDTH and HEIGHT; the dimensions of the total screen size. */
 113 extern void window_initialize_windows (int width, int height);
 114
 115 /* Make a new window showing NODE, and return that window structure.
 116    The new window is made to be the active window.  If NODE is passed
 117    as NULL, then show the node showing in the active window.  If the
 118    window could not be made return a NULL pointer.  The active window
 119    is not changed.*/
 120 extern WINDOW *window_make_window (NODE *node);
 121
 122 /* Delete WINDOW from the list of known windows.  If this window was the
 123    active window, make the next window in the chain be the active window,
 124    or the previous window in the chain if there is no next window. */
 125 extern void window_delete_window (WINDOW *window);
 126
 127 /* A function to call when the screen changes size, and some windows have
 128    to get deleted.  The function is called with the window to be deleted
 129    as an argument, and it can't do anything about the window getting deleted;
 130    it can only clean up dangling references to that window. */
 131 extern VFunction *window_deletion_notifier;
 132
 133 /* Set WINDOW to display NODE. */
 134 extern void window_set_node_of_window (WINDOW *window, NODE *node);
 135
 136 /* Tell the window system that the size of the screen has changed.  This
 137    causes lots of interesting things to happen.  The permanent windows
 138    are resized, as well as every visible window.  You pass WIDTH and HEIGHT;
 139    the dimensions of the total screen size. */
 140 extern void window_new_screen_size (int width, int height);
 141
 142 /* Change the height of WINDOW by AMOUNT.  This also automagically adjusts
 143    the previous and next windows in the chain.  If there is only one user
 144    window, then no change takes place. */
 145 extern void window_change_window_height (WINDOW *window, int amount);
 146
 147 /* Adjust the pagetop of WINDOW such that the cursor point will be visible. */
 148 extern void window_adjust_pagetop (WINDOW *window);
 149
 150 /* Tile all of the windows currently displayed in the global variable
 151    WINDOWS.  If argument DO_INTERNALS is non-zero, tile windows displaying
 152    internal nodes as well. */
 153 #define DONT_TILE_INTERNALS 0
 154 #define TILE_INTERNALS      1
 155 extern void window_tile_windows (int style);
 156
 157 /* Toggle the state of line wrapping in WINDOW.  This can do a bit of fancy
 158    redisplay. */
 159 extern void window_toggle_wrap (WINDOW *window);
 160
 161 /* For every window in CHAIN, set the flags member to have FLAG set. */
 162 extern void window_mark_chain (WINDOW *chain, int flag);
 163
 164 /* For every window in CHAIN, clear the flags member of FLAG. */
 165 extern void window_unmark_chain (WINDOW *chain, int flag);
 166
 167 /* Make WINDOW start displaying at PERCENT percentage of its node. */
 168 extern void window_goto_percentage (WINDOW *window, int percent);
 169
 170 /* Build a new node which has FORMAT printed with ARG1 and ARG2 as the
 171    contents. */
 172 extern NODE *build_message_node (char *format, void *arg1, void *arg2);
 173
 174 /* Useful functions can be called from outside of window.c. */
 175 extern void initialize_message_buffer (void);
 176
 177 /* Print FORMAT with ARG1,2 to the end of the current message buffer. */
 178 extern void printf_to_message_buffer (char *format, void *arg1, void *arg2,
 179     void *arg3);
 180
 181 /* Convert the contents of the message buffer to a node. */
 182 extern NODE *message_buffer_to_node (void);
 183
 184 /* Return the length of the most recently printed line in message buffer. */
 185 extern int message_buffer_length_this_line (void);
 186
 187 /* Pad STRING to COUNT characters by inserting blanks. */
 188 extern int pad_to (int count, char *string);
 189
 190 /* Make a message appear in the echo area, built from FORMAT, ARG1 and ARG2.
 191    The arguments are treated similar to printf () arguments, but not all of
 192    printf () hair is present.  The message appears immediately.  If there was
 193    already a message appearing in the echo area, it is removed. */
 194 extern void window_message_in_echo_area (char *format, void *arg1, void *arg2);
 195
 196 /* Place a temporary message in the echo area built from FORMAT, ARG1
 197    and ARG2.  The message appears immediately, but does not destroy
 198    any existing message.  A future call to unmessage_in_echo_area ()
 199    restores the old contents. */
 200 extern void message_in_echo_area (char *format, void *arg1, void *arg2);
 201 extern void unmessage_in_echo_area (void);
 202
 203 /* Clear the echo area, removing any message that is already present.
 204    The echo area is cleared immediately. */
 205 extern void window_clear_echo_area (void);
 206
 207 /* Quickly guess the approximate number of lines to that NODE would
 208    take to display.  This really only counts carriage returns. */
 209 extern int window_physical_lines (NODE *node);
 210
 211 /* Calculate a list of line starts for the node belonging to WINDOW.  The line
 212    starts are pointers to the actual text within WINDOW->NODE. */
 213 extern void calculate_line_starts (WINDOW *window);
 214
 215 /* Given WINDOW, recalculate the line starts for the node it displays. */
 216 extern void recalculate_line_starts (WINDOW *window);
 217
 218 /* Return the number of characters it takes to display CHARACTER on the
 219    screen at HPOS. */
 220 extern int character_width (int character, int hpos);
 221
 222 /* Return the number of characters it takes to display STRING on the
 223    screen at HPOS. */
 224 extern int string_width (char *string, int hpos);
 225
 226 /* Return the index of the line containing point. */
 227 extern int window_line_of_point (WINDOW *window);
 228
 229 /* Get and return the goal column for this window. */
 230 extern int window_get_goal_column (WINDOW *window);
 231
 232 /* Get and return the printed column offset of the cursor in this window. */
 233 extern int window_get_cursor_column (WINDOW *window);
 234
 235 /* Get and Set the node, pagetop, and point of WINDOW. */
 236 extern void window_get_state (WINDOW *window, SEARCH_STATE *state);
 237 extern void window_set_state (WINDOW *window, SEARCH_STATE *state);
 238
 239 /* Count the number of characters in LINE that precede the printed column
 240    offset of GOAL. */
 241 extern int window_chars_to_goal (char *line, int goal);
 242
 243 #endif /* not INFO_WINDOW_H */