|
|
1.1 root 1: /* Header file for the buffer manipulation primitives.
2: Copyright (C) 1985, 1986, 1990 Free Software Foundation, Inc.
3:
4: This file is part of GNU Emacs.
5:
6: GNU Emacs is free software; you can redistribute it and/or modify
7: it under the terms of the GNU General Public License as published by
8: the Free Software Foundation; either version 1, or (at your option)
9: any later version.
10:
11: GNU Emacs is distributed in the hope that it will be useful,
12: but WITHOUT ANY WARRANTY; without even the implied warranty of
13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14: GNU General Public License for more details.
15:
16: You should have received a copy of the GNU General Public License
17: along with GNU Emacs; see the file COPYING. If not, write to
18: the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
19:
20:
21: #define SET_PT PT =
22:
23: /* Just for laughs, use the same names as in ITS TECO, around 1973. */
24:
25: /* Character position of beginning of buffer. */
26: #define BEG (1)
27: /* Character position of beginning of accessible range of buffer. */
28: #define BEGV (current_buffer->text.begv)
29: /* Character position of point in buffer. */
30: #define PT (current_buffer->text.pt)
31: /* Character position of gap in buffer. */
32: #define GPT (current_buffer->text.gpt)
33: /* Character position of end of accessible range of buffer. */
34: #define ZV (current_buffer->text.zv)
35: /* Character position of end of buffer. */
36: #define Z (current_buffer->text.z)
37: /* Modification count. */
38: #define MODIFF (current_buffer->text.modiff)
39:
40: /* Address of beginning of buffer. */
41: #define BEG_ADDR (current_buffer->text.beg)
42: /* Address of beginning of accessible range of buffer. */
43: #define BEGV_ADDR (&FETCH_CHAR (current_buffer->text.begv))
44: /* Address of point in buffer. */
45: #define PT_ADDR (&FETCH_CHAR (current_buffer->text.pt))
46: /* Address of beginning of gap in buffer. */
47: #define GPT_ADDR (current_buffer->text.beg + current_buffer->text.gpt - 1)
48: /* Address of end of gap in buffer. */
49: #define GAP_END_ADDR (current_buffer->text.beg + current_buffer->text.gpt + current_buffer->text.gap_size - 1)
50: /* Address of end of accessible range of buffer. */
51: #define ZV_ADDR (&FETCH_CHAR (current_buffer->text.zv))
52:
53: /* Size of gap. */
54: #define GAP_SIZE (current_buffer->text.gap_size)
55:
56: /* Now similar macros for a specified buffer.
57: Note that many of these evaluate the buffer argument more than once. */
58:
59: /* Character position of beginning of buffer. */
60: #define BUF_BEG(buf) (1)
61: /* Character position of beginning of accessible range of buffer. */
62: #define BUF_BEGV(buf) ((buf)->text.begv)
63: /* Character position of point in buffer. */
64: #define BUF_PT(buf) ((buf)->text.pt)
65: /* Character position of gap in buffer. */
66: #define BUF_GPT(buf) ((buf)->text.gpt)
67: /* Character position of end of accessible range of buffer. */
68: #define BUF_ZV(buf) ((buf)->text.zv)
69: /* Character position of end of buffer. */
70: #define BUF_Z(buf) ((buf)->text.z)
71: /* Modification count. */
72: #define BUF_MODIFF(buf) ((buf)->text.modiff)
73:
74: /* Address of beginning of buffer. */
75: #define BUF_BEG_ADDR(buf) ((buf)->text.beg)
76:
77: /* Macro for setting the value of BUF_ZV (BUF) to VALUE,
78: by varying the end of the accessible region. */
79: #define SET_BUF_ZV(buf, value) ((buf)->text.zv = (value))
80: #define SET_BUF_PT(buf, value) ((buf)->text.pt = (value))
81:
82: /* Size of gap. */
83: #define BUF_GAP_SIZE(buf) ((buf)->text.gap_size)
84:
85: /* Return the address of character at position POS in buffer BUF.
86: Note that both arguments can be computed more than once. */
87: #define BUF_CHAR_ADDRESS(buf, pos) \
88: ((buf)->text.beg + (pos) - 1 \
89: + ((pos) >= (buf)->text.gpt ? (buf)->text.gap_size : 0))
90:
91: /* Convert the address of a char in the buffer into a character position. */
92: #define PTR_CHAR_POS(ptr) \
93: ((ptr) - (current_buffer)->text.beg \
94: - (ptr - (current_buffer)->text.beg < (unsigned) GPT ? 0 : GAP_SIZE))
95:
96: struct buffer_text
97: {
98: /* Actual address of buffer contents. */
99: unsigned char *beg;
100: /* Values of BEGV ... Z in this buffer. */
101: int begv;
102: int pt;
103: int gpt;
104: int zv;
105: int z;
106: /* Value of GAP_SIZE in this buffer. */
107: int gap_size;
108: /* This counts buffer-modification events for this buffer.
109: It is incremented for each such event, and never otherwise changed. */
110: int modiff;
111: };
112:
113: struct buffer
114: {
115: /* Everything before the `name' slot must be of a non-Lisp_Object type,
116: and every slot after `name' must be a Lisp_Object
117: This is known about by both mark_buffer (alloc.c) and
118: Flist_buffer_local_variables (buffer.c)
119: */
120: /* This structure holds the coordinates of the buffer contents. */
121: struct buffer_text text;
122: /* Next buffer, in chain of all buffers including killed buffers.
123: This chain is used only for garbage collection, in order to
124: collect killed buffers properly. */
125: struct buffer *next;
126: /* Flags saying which DEFVAR_PER_BUFFER variables
127: are local to this buffer. */
128: int local_var_flags;
129: /* Value of text.modified as of when visited file was read or written. */
130: int save_modified;
131: /* the value of text.modified at the last auto-save. */
132: int auto_save_modified;
133: /* Set to the modtime of the visited file when read or written.
134: -1 means visited file was nonexistent.
135: 0 means visited file modtime unknown; in no case complain
136: about any mismatch on next save attempt. */
137: int modtime;
138: /* Position in buffer at which display started
139: the last time this buffer was displayed */
140: int last_window_start;
141:
142: /* This is a special exception -- as this slot should not be
143: marked by gc_sweep, and as it is not lisp-accessible as
144: a local variable -- so re regard it as not really being of type
145: Lisp_Object */
146: /* the markers that refer to this buffer.
147: This is actually a single marker ---
148: successive elements in its marker `chain'
149: are the other markers referring to this
150: buffer */
151: Lisp_Object markers;
152:
153:
154: /* Everything from here down must be a Lisp_Object */
155:
156:
157: /* the name of this buffer */
158: Lisp_Object name;
159: /* the name of the file associated with this buffer */
160: Lisp_Object filename;
161: /* Dir for expanding relative pathnames */
162: Lisp_Object directory;
163: /* True iff this buffer has been been backed
164: up (if you write to its associated file
165: and it hasn't been backed up, then a
166: backup will be made) */
167: /* This isn't really used by the C code, so could be deleted. */
168: Lisp_Object backed_up;
169: /* Length of file when last read or saved. */
170: Lisp_Object save_length;
171: /* file name used for auto-saving this buffer */
172: Lisp_Object auto_save_file_name;
173: /* Non-nil if buffer read-only */
174: Lisp_Object read_only;
175: /* "The mark"; no longer allowed to be nil */
176: Lisp_Object mark;
177:
178: /* Alist of elements (SYMBOL . VALUE-IN-THIS-BUFFER)
179: for all per-buffer variables of this buffer. */
180: Lisp_Object local_var_alist;
181:
182:
183: /* Symbol naming major mode (eg lisp-mode) */
184: Lisp_Object major_mode;
185: /* Pretty name of major mode (eg "Lisp") */
186: Lisp_Object mode_name;
187: /* Format description for mode line */
188: Lisp_Object mode_line_format;
189:
190: /* Keys that are bound local to this buffer */
191: Lisp_Object keymap;
192: /* This buffer's local abbrev table */
193: Lisp_Object abbrev_table;
194: /* This buffer's syntax table. */
195: Lisp_Object syntax_table;
196:
197: /* Values of several buffer-local variables */
198: /* tab-width is buffer-local so that redisplay can find it
199: in buffers that are not current */
200: Lisp_Object case_fold_search;
201: Lisp_Object tab_width;
202: Lisp_Object fill_column;
203: Lisp_Object left_margin;
204: /* Function to call when insert space past fiull column */
205: Lisp_Object auto_fill_hook;
206:
207: /* Non-nil means do not display continuation lines */
208: Lisp_Object truncate_lines;
209: /* Non-nil means display ctl chars with uparrow */
210: Lisp_Object ctl_arrow;
211: /* Non-nil means do selective display;
212: See doc string in syms_of_buffer (buffer.c) for details. */
213: Lisp_Object selective_display;
214: /* Non-nil means show ... at end of line followed by invisible lines. */
215: Lisp_Object selective_display_ellipses;
216: /* t if "self-insertion" should overwrite */
217: Lisp_Object overwrite_mode;
218: /* non-nil means abbrev mode is on. Expand abbrevs automatically. */
219: Lisp_Object abbrev_mode;
220: /* Changes in the buffer are recorded here for undo.
221: t means don't record anything. */
222: Lisp_Object undo_list;
223: };
224:
225: extern struct buffer *current_buffer; /* points to the current buffer */
226:
227: /* This structure holds the default values of the buffer-local variables
228: defined with DefBufferLispVar, that have special slots in each buffer.
229: The default value occupies the same slot in this structure
230: as an individual buffer's value occupies in that buffer.
231: Setting the default value also goes through the alist of buffers
232: and stores into each buffer that does not say it has a local value. */
233:
234: extern struct buffer buffer_defaults;
235:
236: /* This structure marks which slots in a buffer have corresponding
237: default values in buffer_defaults.
238: Each such slot has a nonzero value in this structure.
239: The value has only one nonzero bit.
240:
241: When a buffer has its own local value for a slot,
242: the bit for that slot (found in the same slot in this structure)
243: is turned on in the buffer's local_var_flags slot.
244:
245: If a slot in this structure is zero, then even though there may
246: be a DefBufferLispVar for the slot, there is no default valuefeor it;
247: and the corresponding slot in buffer_defaults is not used. */
248:
249: extern struct buffer buffer_local_flags;
250:
251: /* For each buffer slot, this points to the Lisp symbol name
252: for that slot in the current buffer. It is 0 for slots
253: that don't have such names. */
254:
255: extern struct buffer buffer_local_symbols;
256:
257: /* Some aliases for info about the current buffer. */
258:
259: #define point current_buffer->text.pt
260:
261: /* Return character at position n. No range checking */
262: #define FETCH_CHAR(n) *(((n)>= GPT ? GAP_SIZE : 0) + (n) + BEG_ADDR - 1)
263:
264: /* BufferSafeCeiling (resp. BufferSafeFloor), when applied to n, return */
265: /* the max (resp. min) p such that &FETCH_CHAR (p) - &FETCH_CHAR (n) == p - n */
266: #define BufferSafeCeiling(n) (((n) < GPT && GPT < ZV ? GPT : ZV) - 1)
267:
268: #define BufferSafeFloor(n) (BEGV <= GPT && GPT <= (n) ? GPT : BEGV)
269:
270: extern void reset_buffer ();
This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.