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Diffstat (limited to 'src/window.h')
| -rw-r--r-- | src/window.h | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/src/window.h b/src/window.h new file mode 100644 index 00000000000..18cc318ad2c --- /dev/null +++ b/src/window.h @@ -0,0 +1,204 @@ +/* Window definitions for GNU Emacs. + Copyright (C) 1985, 1986 Free Software Foundation, Inc. + +This file is part of GNU Emacs. + +GNU Emacs is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 1, or (at your option) +any later version. + +GNU Emacs is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Emacs; see the file COPYING. If not, write to +the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + + +/* Windows are allocated as if they were vectors, but then the +Lisp data type is changed to Lisp_Window. They are garbage +collected along with the vectors. + +All windows in use are arranged into a tree, with pointers up and down. + +Windows that are leaves of the tree are actually displayed +and show the contents of buffers. Windows that are not leaves +are used for representing the way groups of leaf windows are +arranged on the screen. Leaf windows never become non-leaves. +They are deleted only by calling delete-window on them (but +this can be done implicitly). Combination windows can be created +and deleted at any time. + +A leaf window has a non-nil buffer field, and also + has markers in its start and pointm fields. Non-leaf windows + have nil in these fields. + +Non-leaf windows are either vertical or horizontal combinations. + +A vertical combination window has children that are arranged +one above the next. Its vchild field points to the uppermost child. +The parent field of each of the children points to the vertical +combination window. The next field of each child points to the +child below it, or is nil for the lowest child. The prev field +or each child points to the child above it, or is nil for the highest child. + +A horizontal combination window has children that are side by side. +Its hchild field points to the leftmost child. In each child +the next field points to the child to the right and the prev field +points to the child to the left. + +The children of a vertical combination window may be leaf windows +or horizontal combination windows. The children of a horizontal +combination window may be leaf windows or vertical combination windows. + +At the top of the tree are two windows which have nil as parent. +The second of these is minibuf_window. The first one manages all +the screen area that is not minibuffer, and is called the root window. +Different windows can be the root at different times; +initially the root window is a leaf window, but if more windows +are created then that leaf window ceases to be root and a newly +made combination window becomes root instead. + +In any case, prev of the minibuf window is the root window and +next of the root window is the minibuf window. To find the +root window at any time, do XWINDOW (minibuf_window)->prev. + +*/ + +struct window + { + /* The first two fields are really the header of a vector */ + /* The window code does not refer to them. */ + int size; + struct Lisp_Vector *vec_next; + /* Following child (to right or down) at same level of tree */ + Lisp_Object next; + /* Preceding child (to left or up) at same level of tree */ + Lisp_Object prev; + /* First child of this window. */ + /* vchild is used if this is a vertical combination, + hchild if this is a horizontal combination. */ + Lisp_Object hchild, vchild; + /* The window this one is a child of. */ + Lisp_Object parent; + /* The upper left corner coordinates of this window, + as integers relative to upper left corner of screen = 0, 0 */ + Lisp_Object left; + Lisp_Object top; + /* The size of the window */ + Lisp_Object height; + Lisp_Object width; + /* The buffer displayed in this window */ + /* Of the fields vchild, hchild and buffer, only one is non-nil. */ + Lisp_Object buffer; + /* A marker pointing to where in the text to start displaying */ + Lisp_Object start; + /* A marker pointing to where in the text point is in this window, + used only when the window is not selected. + This exists so that when multiple windows show one buffer + each one can have its own value of point. */ + Lisp_Object pointm; + /* Non-nil means next redisplay must use the value of start + set up for it in advance. Set by scrolling commands. */ + Lisp_Object force_start; + /* Number of columns display within the window is scrolled to the left. */ + Lisp_Object hscroll; + /* Number saying how recently window was selected */ + Lisp_Object use_time; + /* Unique number of window assigned when it was created */ + Lisp_Object sequence_number; + /* No permanent meaning; used by save-window-excursion's bookkeeping */ + Lisp_Object temslot; + /* text.modified of displayed buffer as of last time display completed */ + Lisp_Object last_modified; + /* Value of point at that time */ + Lisp_Object last_point; +/* The rest are currently not used or only half used */ + /* Screen coords of point at that time */ + Lisp_Object last_point_x; + Lisp_Object last_point_y; + /* Screen coords of mark as of last time display completed */ + /* May be nil if mark does not exist or was not on screen */ + Lisp_Object last_mark_x; + Lisp_Object last_mark_y; + /* Number of characters in buffer past bottom of window, + as of last redisplay that finished. */ + Lisp_Object window_end_pos; + /* t if window_end_pos is truly valid. + This is nil if nontrivial redisplay is preempted + since in that case the screen image that window_end_pos + did not get onto the screen. */ + Lisp_Object window_end_valid; + /* Vertical position (relative to window top) of that buffer position + of the first of those characters */ + Lisp_Object window_end_vpos; + /* Non-nil means must regenerate mode line of this window */ + Lisp_Object update_mode_line; + /* Non-nil means current value of `start' + was the beginning of a line when it was chosen. */ + Lisp_Object start_at_line_beg; + }; + +/* This is the window which displays the minibuffer. + It is always the same window. */ + +extern Lisp_Object minibuf_window; + +/* This is the window in which the terminal's cursor should + be left when nothing is being done with it. This must + always be a leaf window, and its buffer is selected by + the top level editing loop at the end of each command. */ + +extern Lisp_Object selected_window; + +/* Non-nil => window to for C-M-v to scroll + when the minibuffer is selected. */ +extern Lisp_Object Vminibuf_scroll_window; + +extern Lisp_Object Fnext_window (); +extern Lisp_Object Fselect_window (); +extern Lisp_Object Fdisplay_buffer (); +extern Lisp_Object Fset_window_buffer (); + +/* Prompt to display in front of the minibuffer contents. */ +extern char *minibuf_prompt; + +/* Message to display instead of minibuffer contents. */ +extern char *echo_area_contents; + +/* Last message that was displayed in the echo area. */ +extern char *prev_echo_area_contents; + +/* Depth in minibuffer invocations. */ +extern int minibuf_level; + +/* Nonzero means redisplay all mode lines. */ +extern int update_mode_lines; + +/* Minimum value of GPT since last redisplay that finished. */ + +extern int beg_unchanged; + +/* Minimum value of Z-GPT since last redisplay that finished. */ + +extern int end_unchanged; + +/* MODIFF as of last redisplay that finished; + if it matches MODIFF, beg_unchanged and end_unchanged + contain no useful information */ +extern int unchanged_modified; + +/* Nonzero if BEGV-BEG or Z-ZV of current buffer has changed + since last redisplay that finished */ +extern int clip_changed; + +/* Nonzero if window sizes or contents have changed + since last redisplay that finished */ +extern int windows_or_buffers_changed; + +/* Number of windows displaying the selected buffer. + Normally this is 1, but it can be more. */ +extern int buffer_shared; |