| 1 | /* Header file for the buffer manipulation primitives. |
| 2 | Copyright (C) 1985, 86, 93, 94, 95, 97, 1998, 1999, 2000, 2001 |
| 3 | 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., 59 Temple Place - Suite 330, |
| 20 | Boston, MA 02111-1307, USA. */ |
| 21 | |
| 22 | |
| 23 | /* Accessing the parameters of the current buffer. */ |
| 24 | |
| 25 | /* These macros come in pairs, one for the char position |
| 26 | and one for the byte position. */ |
| 27 | |
| 28 | /* Position of beginning of buffer. */ |
| 29 | #define BEG (1) |
| 30 | #define BEG_BYTE (1) |
| 31 | |
| 32 | /* Position of beginning of accessible range of buffer. */ |
| 33 | #define BEGV (current_buffer->begv) |
| 34 | #define BEGV_BYTE (current_buffer->begv_byte) |
| 35 | |
| 36 | /* Position of point in buffer. The "+ 0" makes this |
| 37 | not an l-value, so you can't assign to it. Use SET_PT instead. */ |
| 38 | #define PT (current_buffer->pt + 0) |
| 39 | #define PT_BYTE (current_buffer->pt_byte + 0) |
| 40 | |
| 41 | /* Position of gap in buffer. */ |
| 42 | #define GPT (current_buffer->text->gpt) |
| 43 | #define GPT_BYTE (current_buffer->text->gpt_byte) |
| 44 | |
| 45 | /* Position of end of accessible range of buffer. */ |
| 46 | #define ZV (current_buffer->zv) |
| 47 | #define ZV_BYTE (current_buffer->zv_byte) |
| 48 | |
| 49 | /* Position of end of buffer. */ |
| 50 | #define Z (current_buffer->text->z) |
| 51 | #define Z_BYTE (current_buffer->text->z_byte) |
| 52 | |
| 53 | /* Macros for the addresses of places in the buffer. */ |
| 54 | |
| 55 | /* Address of beginning of buffer. */ |
| 56 | #define BEG_ADDR (current_buffer->text->beg) |
| 57 | |
| 58 | /* Address of beginning of accessible range of buffer. */ |
| 59 | #define BEGV_ADDR (BYTE_POS_ADDR (current_buffer->begv_byte)) |
| 60 | |
| 61 | /* Address of point in buffer. */ |
| 62 | #define PT_ADDR (BYTE_POS_ADDR (current_buffer->pt_byte)) |
| 63 | |
| 64 | /* Address of beginning of gap in buffer. */ |
| 65 | #define GPT_ADDR (current_buffer->text->beg + current_buffer->text->gpt_byte - 1) |
| 66 | |
| 67 | /* Address of end of gap in buffer. */ |
| 68 | #define GAP_END_ADDR (current_buffer->text->beg + current_buffer->text->gpt_byte + current_buffer->text->gap_size - 1) |
| 69 | |
| 70 | /* Address of end of accessible range of buffer. */ |
| 71 | #define ZV_ADDR (BYTE_POS_ADDR (current_buffer->zv_byte)) |
| 72 | |
| 73 | /* Address of end of buffer. */ |
| 74 | #define Z_ADDR (current_buffer->text->beg + current_buffer->text->gap_size + current_buffer->text->z_byte - 1) |
| 75 | |
| 76 | /* Size of gap. */ |
| 77 | #define GAP_SIZE (current_buffer->text->gap_size) |
| 78 | |
| 79 | /* Is the current buffer narrowed? */ |
| 80 | #define NARROWED ((BEGV != BEG) || (ZV != Z)) |
| 81 | |
| 82 | /* Modification count. */ |
| 83 | #define MODIFF (current_buffer->text->modiff) |
| 84 | |
| 85 | /* Overlay modification count. */ |
| 86 | #define OVERLAY_MODIFF (current_buffer->text->overlay_modiff) |
| 87 | |
| 88 | /* Modification count as of last visit or save. */ |
| 89 | #define SAVE_MODIFF (current_buffer->text->save_modiff) |
| 90 | |
| 91 | /* BUFFER_CEILING_OF (resp. BUFFER_FLOOR_OF), when applied to n, return |
| 92 | the max (resp. min) p such that |
| 93 | |
| 94 | BYTE_POS_ADDR (p) - BYTE_POS_ADDR (n) == p - n */ |
| 95 | |
| 96 | #define BUFFER_CEILING_OF(BYTEPOS) \ |
| 97 | (((BYTEPOS) < GPT_BYTE && GPT < ZV ? GPT_BYTE : ZV_BYTE) - 1) |
| 98 | #define BUFFER_FLOOR_OF(BYTEPOS) \ |
| 99 | (BEGV <= GPT && GPT_BYTE <= (BYTEPOS) ? GPT_BYTE : BEGV_BYTE) |
| 100 | \f |
| 101 | /* Similar macros to operate on a specified buffer. |
| 102 | Note that many of these evaluate the buffer argument more than once. */ |
| 103 | |
| 104 | /* Position of beginning of buffer. */ |
| 105 | #define BUF_BEG(buf) (1) |
| 106 | #define BUF_BEG_BYTE(buf) (1) |
| 107 | |
| 108 | /* Position of beginning of accessible range of buffer. */ |
| 109 | #define BUF_BEGV(buf) ((buf)->begv) |
| 110 | #define BUF_BEGV_BYTE(buf) ((buf)->begv_byte) |
| 111 | |
| 112 | /* Position of point in buffer. */ |
| 113 | #define BUF_PT(buf) ((buf)->pt) |
| 114 | #define BUF_PT_BYTE(buf) ((buf)->pt_byte) |
| 115 | |
| 116 | /* Position of gap in buffer. */ |
| 117 | #define BUF_GPT(buf) ((buf)->text->gpt) |
| 118 | #define BUF_GPT_BYTE(buf) ((buf)->text->gpt_byte) |
| 119 | |
| 120 | /* Position of end of accessible range of buffer. */ |
| 121 | #define BUF_ZV(buf) ((buf)->zv) |
| 122 | #define BUF_ZV_BYTE(buf) ((buf)->zv_byte) |
| 123 | |
| 124 | /* Position of end of buffer. */ |
| 125 | #define BUF_Z(buf) ((buf)->text->z) |
| 126 | #define BUF_Z_BYTE(buf) ((buf)->text->z_byte) |
| 127 | |
| 128 | /* Address of beginning of buffer. */ |
| 129 | #define BUF_BEG_ADDR(buf) ((buf)->text->beg) |
| 130 | |
| 131 | /* Address of beginning of gap of buffer. */ |
| 132 | #define BUF_GPT_ADDR(buf) ((buf)->text->beg + (buf)->text->gpt_byte - 1) |
| 133 | |
| 134 | /* Address of end of buffer. */ |
| 135 | #define BUF_Z_ADDR(buf) ((buf)->text->beg + (buf)->text->gap_size + (buf)->text->z_byte - 1) |
| 136 | |
| 137 | /* Address of end of gap in buffer. */ |
| 138 | #define BUF_GAP_END_ADDR(buf) ((buf)->text->beg + (buf)->text->gpt_byte + (buf)->text->gap_size - 1) |
| 139 | |
| 140 | /* Size of gap. */ |
| 141 | #define BUF_GAP_SIZE(buf) ((buf)->text->gap_size) |
| 142 | |
| 143 | /* Is this buffer narrowed? */ |
| 144 | #define BUF_NARROWED(buf) ((BUF_BEGV (buf) != BUF_BEG (buf)) \ |
| 145 | || (BUF_ZV (buf) != BUF_Z (buf))) |
| 146 | |
| 147 | /* Modification count. */ |
| 148 | #define BUF_MODIFF(buf) ((buf)->text->modiff) |
| 149 | |
| 150 | /* Modification count as of last visit or save. */ |
| 151 | #define BUF_SAVE_MODIFF(buf) ((buf)->text->save_modiff) |
| 152 | |
| 153 | /* Overlay modification count. */ |
| 154 | #define BUF_OVERLAY_MODIFF(buf) ((buf)->text->overlay_modiff) |
| 155 | |
| 156 | /* Interval tree of buffer. */ |
| 157 | #define BUF_INTERVALS(buf) ((buf)->text->intervals) |
| 158 | |
| 159 | /* Marker chain of buffer. */ |
| 160 | #define BUF_MARKERS(buf) ((buf)->text->markers) |
| 161 | |
| 162 | #define BUF_UNCHANGED_MODIFIED(buf) \ |
| 163 | ((buf)->text->unchanged_modified) |
| 164 | |
| 165 | #define BUF_OVERLAY_UNCHANGED_MODIFIED(buf) \ |
| 166 | ((buf)->text->overlay_unchanged_modified) |
| 167 | #define BUF_BEG_UNCHANGED(buf) ((buf)->text->beg_unchanged) |
| 168 | #define BUF_END_UNCHANGED(buf) ((buf)->text->end_unchanged) |
| 169 | |
| 170 | #define UNCHANGED_MODIFIED \ |
| 171 | BUF_UNCHANGED_MODIFIED (current_buffer) |
| 172 | #define OVERLAY_UNCHANGED_MODIFIED \ |
| 173 | BUF_OVERLAY_UNCHANGED_MODIFIED (current_buffer) |
| 174 | #define BEG_UNCHANGED BUF_BEG_UNCHANGED (current_buffer) |
| 175 | #define END_UNCHANGED BUF_END_UNCHANGED (current_buffer) |
| 176 | |
| 177 | /* Compute how many characters at the top and bottom of BUF are |
| 178 | unchanged when the range START..END is modified. This computation |
| 179 | must be done each time BUF is modified. */ |
| 180 | |
| 181 | #define BUF_COMPUTE_UNCHANGED(buf, start, end) \ |
| 182 | do \ |
| 183 | { \ |
| 184 | if (BUF_UNCHANGED_MODIFIED (buf) == BUF_MODIFF (buf) \ |
| 185 | && (BUF_OVERLAY_UNCHANGED_MODIFIED (buf) \ |
| 186 | == BUF_OVERLAY_MODIFF (buf))) \ |
| 187 | { \ |
| 188 | BUF_BEG_UNCHANGED (buf) = (start) - BUF_BEG (buf); \ |
| 189 | BUF_END_UNCHANGED (buf) = BUF_Z (buf) - (end); \ |
| 190 | } \ |
| 191 | else \ |
| 192 | { \ |
| 193 | if (BUF_Z (buf) - (end) < BUF_END_UNCHANGED (buf)) \ |
| 194 | BUF_END_UNCHANGED (buf) = BUF_Z (buf) - (end); \ |
| 195 | if ((start) - BUF_BEG (buf) < BUF_BEG_UNCHANGED (buf)) \ |
| 196 | BUF_BEG_UNCHANGED (buf) = (start) - BUF_BEG (buf); \ |
| 197 | } \ |
| 198 | } \ |
| 199 | while (0) |
| 200 | |
| 201 | \f |
| 202 | /* Macros to set PT in the current buffer, or another buffer. */ |
| 203 | |
| 204 | #define SET_PT(position) (set_point (current_buffer, (position))) |
| 205 | #define TEMP_SET_PT(position) (temp_set_point (current_buffer, (position))) |
| 206 | |
| 207 | #define SET_PT_BOTH(position, byte) \ |
| 208 | (set_point_both (current_buffer, (position), (byte))) |
| 209 | #define TEMP_SET_PT_BOTH(position, byte) \ |
| 210 | (temp_set_point_both (current_buffer, (position), (byte))) |
| 211 | |
| 212 | #define BUF_SET_PT(buffer, position) \ |
| 213 | (set_point ((buffer), (position))) |
| 214 | #define BUF_TEMP_SET_PT(buffer, position) \ |
| 215 | (temp_set_point ((buffer), (position))) |
| 216 | |
| 217 | extern void set_point P_ ((struct buffer *, int)); |
| 218 | extern INLINE void temp_set_point P_ ((struct buffer *, int)); |
| 219 | extern void set_point_both P_ ((struct buffer *, int, int)); |
| 220 | extern INLINE void temp_set_point_both P_ ((struct buffer *, int, int)); |
| 221 | extern void enlarge_buffer_text P_ ((struct buffer *, int)); |
| 222 | |
| 223 | \f |
| 224 | /* Macros for setting the BEGV, ZV or PT of a given buffer. |
| 225 | |
| 226 | SET_BUF_PT* seet to be redundant. Get rid of them? |
| 227 | |
| 228 | The ..._BOTH macros take both a charpos and a bytepos, |
| 229 | which must correspond to each other. |
| 230 | |
| 231 | The macros without ..._BOTH take just a charpos, |
| 232 | and compute the bytepos from it. */ |
| 233 | |
| 234 | #define SET_BUF_BEGV(buf, charpos) \ |
| 235 | ((buf)->begv_byte = buf_charpos_to_bytepos ((buf), (charpos)), \ |
| 236 | (buf)->begv = (charpos)) |
| 237 | |
| 238 | #define SET_BUF_ZV(buf, charpos) \ |
| 239 | ((buf)->zv_byte = buf_charpos_to_bytepos ((buf), (charpos)), \ |
| 240 | (buf)->zv = (charpos)) |
| 241 | |
| 242 | #define SET_BUF_BEGV_BOTH(buf, charpos, byte) \ |
| 243 | ((buf)->begv = (charpos), \ |
| 244 | (buf)->begv_byte = (byte)) |
| 245 | |
| 246 | #define SET_BUF_ZV_BOTH(buf, charpos, byte) \ |
| 247 | ((buf)->zv = (charpos), \ |
| 248 | (buf)->zv_byte = (byte)) |
| 249 | |
| 250 | #define SET_BUF_PT_BOTH(buf, charpos, byte) \ |
| 251 | ((buf)->pt = (charpos), \ |
| 252 | (buf)->pt_byte = (byte)) |
| 253 | \f |
| 254 | /* Macros to access a character or byte in the current buffer, |
| 255 | or convert between a byte position and an address. |
| 256 | These macros do not check that the position is in range. */ |
| 257 | |
| 258 | /* Access a Lisp position value in POS, |
| 259 | and store the charpos in CHARPOS and the bytepos in BYTEPOS. */ |
| 260 | |
| 261 | #define DECODE_POSITION(charpos, bytepos, pos) \ |
| 262 | if (1) \ |
| 263 | { \ |
| 264 | Lisp_Object __pos = (pos); \ |
| 265 | if (NUMBERP (__pos)) \ |
| 266 | { \ |
| 267 | charpos = __pos; \ |
| 268 | bytepos = buf_charpos_to_bytepos (current_buffer, __pos); \ |
| 269 | } \ |
| 270 | else if (MARKERP (__pos)) \ |
| 271 | { \ |
| 272 | charpos = marker_position (__pos); \ |
| 273 | bytepos = marker_byte_position (__pos); \ |
| 274 | } \ |
| 275 | else \ |
| 276 | wrong_type_argument (Qinteger_or_marker_p, __pos); \ |
| 277 | } \ |
| 278 | else |
| 279 | |
| 280 | /* Return the address of byte position N in current buffer. */ |
| 281 | |
| 282 | #define BYTE_POS_ADDR(n) \ |
| 283 | (((n) >= GPT_BYTE ? GAP_SIZE : 0) + (n) + BEG_ADDR - 1) |
| 284 | |
| 285 | /* Return the address of char position N. */ |
| 286 | |
| 287 | #define CHAR_POS_ADDR(n) \ |
| 288 | (((n) >= GPT ? GAP_SIZE : 0) \ |
| 289 | + buf_charpos_to_bytepos (current_buffer, n) \ |
| 290 | + BEG_ADDR - 1) |
| 291 | |
| 292 | /* Convert a character position to a byte position. */ |
| 293 | |
| 294 | #define CHAR_TO_BYTE(charpos) \ |
| 295 | (buf_charpos_to_bytepos (current_buffer, charpos)) |
| 296 | |
| 297 | /* Convert a byte position to a character position. */ |
| 298 | |
| 299 | #define BYTE_TO_CHAR(bytepos) \ |
| 300 | (buf_bytepos_to_charpos (current_buffer, bytepos)) |
| 301 | |
| 302 | /* Convert PTR, the address of a byte in the buffer, into a byte position. */ |
| 303 | |
| 304 | #define PTR_BYTE_POS(ptr) \ |
| 305 | ((ptr) - (current_buffer)->text->beg \ |
| 306 | - (ptr - (current_buffer)->text->beg < (unsigned) GPT_BYTE ? 0 : GAP_SIZE) \ |
| 307 | + 1) |
| 308 | |
| 309 | /* Return character at position POS. */ |
| 310 | |
| 311 | #define FETCH_CHAR(pos) \ |
| 312 | (!NILP (current_buffer->enable_multibyte_characters) \ |
| 313 | ? FETCH_MULTIBYTE_CHAR ((pos)) \ |
| 314 | : FETCH_BYTE ((pos))) |
| 315 | |
| 316 | /* Return the byte at byte position N. */ |
| 317 | |
| 318 | #define FETCH_BYTE(n) *(BYTE_POS_ADDR ((n))) |
| 319 | |
| 320 | /* Variables used locally in FETCH_MULTIBYTE_CHAR. */ |
| 321 | extern unsigned char *_fetch_multibyte_char_p; |
| 322 | extern int _fetch_multibyte_char_len; |
| 323 | |
| 324 | /* Return character code of multi-byte form at position POS. If POS |
| 325 | doesn't point the head of valid multi-byte form, only the byte at |
| 326 | POS is returned. No range checking. */ |
| 327 | |
| 328 | #define FETCH_MULTIBYTE_CHAR(pos) \ |
| 329 | (_fetch_multibyte_char_p = (((pos) >= GPT_BYTE ? GAP_SIZE : 0) \ |
| 330 | + (pos) + BEG_ADDR - 1), \ |
| 331 | _fetch_multibyte_char_len \ |
| 332 | = ((pos) >= GPT_BYTE ? ZV_BYTE : GPT_BYTE) - (pos), \ |
| 333 | STRING_CHAR (_fetch_multibyte_char_p, _fetch_multibyte_char_len)) |
| 334 | \f |
| 335 | /* Macros for accessing a character or byte, |
| 336 | or converting between byte positions and addresses, |
| 337 | in a specified buffer. */ |
| 338 | |
| 339 | /* Return the address of character at byte position POS in buffer BUF. |
| 340 | Note that both arguments can be computed more than once. */ |
| 341 | |
| 342 | #define BUF_BYTE_ADDRESS(buf, pos) \ |
| 343 | ((buf)->text->beg + (pos) - 1 \ |
| 344 | + ((pos) >= (buf)->text->gpt_byte ? (buf)->text->gap_size : 0)) |
| 345 | |
| 346 | /* Return the address of character at char position POS in buffer BUF. |
| 347 | Note that both arguments can be computed more than once. */ |
| 348 | |
| 349 | #define BUF_CHAR_ADDRESS(buf, pos) \ |
| 350 | ((buf)->text->beg + buf_charpos_to_bytepos ((buf), (pos)) - 1 \ |
| 351 | + ((pos) >= (buf)->text->gpt ? (buf)->text->gap_size : 0)) |
| 352 | |
| 353 | /* Convert PTR, the address of a char in buffer BUF, |
| 354 | into a character position. */ |
| 355 | |
| 356 | #define BUF_PTR_BYTE_POS(buf, ptr) \ |
| 357 | ((ptr) - (buf)->text->beg \ |
| 358 | - (ptr - (buf)->text->beg < (unsigned) BUF_GPT_BYTE ((buf)) \ |
| 359 | ? 0 : BUF_GAP_SIZE ((buf))) \ |
| 360 | + 1) |
| 361 | |
| 362 | /* Return the character at byte position POS in buffer BUF. */ |
| 363 | |
| 364 | #define BUF_FETCH_CHAR(buf, pos) \ |
| 365 | (!NILP (buf->enable_multibyte_characters) \ |
| 366 | ? BUF_FETCH_MULTIBYTE_CHAR ((buf), (pos)) \ |
| 367 | : BUF_FETCH_BYTE ((buf), (pos))) |
| 368 | |
| 369 | /* Return the byte at byte position N in buffer BUF. */ |
| 370 | |
| 371 | #define BUF_FETCH_BYTE(buf, n) \ |
| 372 | *(BUF_BYTE_ADDRESS ((buf), (n))) |
| 373 | |
| 374 | /* Return character code of multi-byte form at byte position POS in BUF. |
| 375 | If POS doesn't point the head of valid multi-byte form, only the byte at |
| 376 | POS is returned. No range checking. */ |
| 377 | |
| 378 | #define BUF_FETCH_MULTIBYTE_CHAR(buf, pos) \ |
| 379 | (_fetch_multibyte_char_p \ |
| 380 | = (((pos) >= BUF_GPT_BYTE (buf) ? BUF_GAP_SIZE (buf) : 0) \ |
| 381 | + (pos) + BUF_BEG_ADDR (buf) - 1), \ |
| 382 | _fetch_multibyte_char_len \ |
| 383 | = (((pos) >= BUF_GPT_BYTE (buf) ? BUF_ZV_BYTE (buf) : BUF_GPT_BYTE (buf)) \ |
| 384 | - (pos)), \ |
| 385 | STRING_CHAR (_fetch_multibyte_char_p, _fetch_multibyte_char_len)) |
| 386 | \f |
| 387 | /* Define the actual buffer data structures. */ |
| 388 | |
| 389 | /* This data structure describes the actual text contents of a buffer. |
| 390 | It is shared between indirect buffers and their base buffer. */ |
| 391 | |
| 392 | struct buffer_text |
| 393 | { |
| 394 | /* Actual address of buffer contents. If REL_ALLOC is defined, |
| 395 | this address might change when blocks are relocated which can |
| 396 | e.g. happen when malloc is called. So, don't pass a pointer |
| 397 | into a buffer's text to functions that malloc. */ |
| 398 | unsigned char *beg; |
| 399 | |
| 400 | int gpt; /* Char pos of gap in buffer. */ |
| 401 | int z; /* Char pos of end of buffer. */ |
| 402 | int gpt_byte; /* Byte pos of gap in buffer. */ |
| 403 | int z_byte; /* Byte pos of end of buffer. */ |
| 404 | int gap_size; /* Size of buffer's gap. */ |
| 405 | int modiff; /* This counts buffer-modification events |
| 406 | for this buffer. It is incremented for |
| 407 | each such event, and never otherwise |
| 408 | changed. */ |
| 409 | int save_modiff; /* Previous value of modiff, as of last |
| 410 | time buffer visited or saved a file. */ |
| 411 | |
| 412 | int overlay_modiff; /* Counts modifications to overlays. */ |
| 413 | |
| 414 | /* Minimum value of GPT - BEG since last redisplay that finished. */ |
| 415 | int beg_unchanged; |
| 416 | |
| 417 | /* Minimum value of Z - GPT since last redisplay that finished. */ |
| 418 | int end_unchanged; |
| 419 | |
| 420 | /* MODIFF as of last redisplay that finished; if it matches MODIFF, |
| 421 | beg_unchanged and end_unchanged contain no useful information. */ |
| 422 | int unchanged_modified; |
| 423 | |
| 424 | /* BUF_OVERLAY_MODIFF of current buffer, as of last redisplay that |
| 425 | finished; if it matches BUF_OVERLAY_MODIFF, beg_unchanged and |
| 426 | end_unchanged contain no useful information. */ |
| 427 | int overlay_unchanged_modified; |
| 428 | |
| 429 | /* Properties of this buffer's text. */ |
| 430 | INTERVAL intervals; |
| 431 | |
| 432 | /* The markers that refer to this buffer. |
| 433 | This is actually a single marker --- |
| 434 | successive elements in its marker `chain' |
| 435 | are the other markers referring to this buffer. */ |
| 436 | Lisp_Object markers; |
| 437 | }; |
| 438 | |
| 439 | /* This is the structure that the buffer Lisp object points to. */ |
| 440 | |
| 441 | struct buffer |
| 442 | { |
| 443 | /* Everything before the `name' slot must be of a non-Lisp_Object type, |
| 444 | and every slot after `name' must be a Lisp_Object. |
| 445 | |
| 446 | Check out mark_buffer (alloc.c) to see why. */ |
| 447 | |
| 448 | EMACS_INT size; |
| 449 | |
| 450 | /* Next buffer, in chain of all buffers including killed buffers. |
| 451 | This chain is used only for garbage collection, in order to |
| 452 | collect killed buffers properly. |
| 453 | Note that vectors and most pseudovectors are all on one chain, |
| 454 | but buffers are on a separate chain of their own. */ |
| 455 | struct buffer *next; |
| 456 | |
| 457 | /* This structure holds the coordinates of the buffer contents |
| 458 | in ordinary buffers. In indirect buffers, this is not used. */ |
| 459 | struct buffer_text own_text; |
| 460 | |
| 461 | /* This points to the `struct buffer_text' that used for this buffer. |
| 462 | In an ordinary buffer, this is the own_text field above. |
| 463 | In an indirect buffer, this is the own_text field of another buffer. */ |
| 464 | struct buffer_text *text; |
| 465 | |
| 466 | /* Char position of point in buffer. */ |
| 467 | int pt; |
| 468 | /* Byte position of point in buffer. */ |
| 469 | int pt_byte; |
| 470 | /* Char position of beginning of accessible range. */ |
| 471 | int begv; |
| 472 | /* Byte position of beginning of accessible range. */ |
| 473 | int begv_byte; |
| 474 | /* Char position of end of accessible range. */ |
| 475 | int zv; |
| 476 | /* Byte position of end of accessible range. */ |
| 477 | int zv_byte; |
| 478 | |
| 479 | /* In an indirect buffer, this points to the base buffer. |
| 480 | In an ordinary buffer, it is 0. */ |
| 481 | struct buffer *base_buffer; |
| 482 | |
| 483 | /* A non-zero value in slot IDX means that per-buffer variable |
| 484 | with index IDX has a local value in this buffer. The index IDX |
| 485 | for a buffer-local variable is stored in that variable's slot |
| 486 | in buffer_local_flags as a Lisp integer. If the index is -1, |
| 487 | this means the variable is always local in all buffers. */ |
| 488 | #define MAX_PER_BUFFER_VARS 50 |
| 489 | char local_flags[MAX_PER_BUFFER_VARS]; |
| 490 | |
| 491 | /* Set to the modtime of the visited file when read or written. |
| 492 | -1 means visited file was nonexistent. |
| 493 | 0 means visited file modtime unknown; in no case complain |
| 494 | about any mismatch on next save attempt. */ |
| 495 | int modtime; |
| 496 | /* The value of text->modiff at the last auto-save. */ |
| 497 | int auto_save_modified; |
| 498 | /* The value of text->modiff at the last display error. |
| 499 | Redisplay of this buffer is inhibited until it changes again. */ |
| 500 | int display_error_modiff; |
| 501 | /* The time at which we detected a failure to auto-save, |
| 502 | Or -1 if we didn't have a failure. */ |
| 503 | int auto_save_failure_time; |
| 504 | /* Position in buffer at which display started |
| 505 | the last time this buffer was displayed. */ |
| 506 | int last_window_start; |
| 507 | |
| 508 | /* Set nonzero whenever the narrowing is changed in this buffer. */ |
| 509 | int clip_changed; |
| 510 | |
| 511 | /* If the long line scan cache is enabled (i.e. the buffer-local |
| 512 | variable cache-long-line-scans is non-nil), newline_cache |
| 513 | points to the newline cache, and width_run_cache points to the |
| 514 | width run cache. |
| 515 | |
| 516 | The newline cache records which stretches of the buffer are |
| 517 | known *not* to contain newlines, so that they can be skipped |
| 518 | quickly when we search for newlines. |
| 519 | |
| 520 | The width run cache records which stretches of the buffer are |
| 521 | known to contain characters whose widths are all the same. If |
| 522 | the width run cache maps a character to a value > 0, that value is |
| 523 | the character's width; if it maps a character to zero, we don't |
| 524 | know what its width is. This allows compute_motion to process |
| 525 | such regions very quickly, using algebra instead of inspecting |
| 526 | each character. See also width_table, below. */ |
| 527 | struct region_cache *newline_cache; |
| 528 | struct region_cache *width_run_cache; |
| 529 | |
| 530 | /* Non-zero means don't use redisplay optimizations for |
| 531 | displaying this buffer. */ |
| 532 | unsigned prevent_redisplay_optimizations_p : 1; |
| 533 | |
| 534 | /* Changes in the buffer are recorded here for undo. |
| 535 | t means don't record anything. |
| 536 | This information belongs to the base buffer of an indirect buffer, |
| 537 | But we can't store it in the struct buffer_text |
| 538 | because local variables have to be right in the struct buffer. |
| 539 | So we copy it around in set_buffer_internal. |
| 540 | This comes before `name' because it is marked in a special way. */ |
| 541 | Lisp_Object undo_list; |
| 542 | |
| 543 | /* Everything from here down must be a Lisp_Object. */ |
| 544 | |
| 545 | /* The name of this buffer. */ |
| 546 | Lisp_Object name; |
| 547 | |
| 548 | /* The name of the file visited in this buffer, or nil. */ |
| 549 | Lisp_Object filename; |
| 550 | /* Dir for expanding relative file names. */ |
| 551 | Lisp_Object directory; |
| 552 | /* True iff this buffer has been backed up (if you write to the |
| 553 | visited file and it hasn't been backed up, then a backup will |
| 554 | be made). */ |
| 555 | /* This isn't really used by the C code, so could be deleted. */ |
| 556 | Lisp_Object backed_up; |
| 557 | /* Length of file when last read or saved. |
| 558 | This is not in the struct buffer_text |
| 559 | because it's not used in indirect buffers at all. */ |
| 560 | Lisp_Object save_length; |
| 561 | /* File name used for auto-saving this buffer. |
| 562 | This is not in the struct buffer_text |
| 563 | because it's not used in indirect buffers at all. */ |
| 564 | Lisp_Object auto_save_file_name; |
| 565 | |
| 566 | /* Non-nil if buffer read-only. */ |
| 567 | Lisp_Object read_only; |
| 568 | /* "The mark". This is a marker which may |
| 569 | point into this buffer or may point nowhere. */ |
| 570 | Lisp_Object mark; |
| 571 | |
| 572 | /* Alist of elements (SYMBOL . VALUE-IN-THIS-BUFFER) |
| 573 | for all per-buffer variables of this buffer. */ |
| 574 | Lisp_Object local_var_alist; |
| 575 | |
| 576 | /* Symbol naming major mode (eg, lisp-mode). */ |
| 577 | Lisp_Object major_mode; |
| 578 | /* Pretty name of major mode (eg, "Lisp"). */ |
| 579 | Lisp_Object mode_name; |
| 580 | /* Mode line element that controls format of mode line. */ |
| 581 | Lisp_Object mode_line_format; |
| 582 | |
| 583 | /* Analogous to mode_line_format for the line displayed at the top |
| 584 | of windows. Nil means don't display that line. */ |
| 585 | Lisp_Object header_line_format; |
| 586 | |
| 587 | /* Keys that are bound local to this buffer. */ |
| 588 | Lisp_Object keymap; |
| 589 | /* This buffer's local abbrev table. */ |
| 590 | Lisp_Object abbrev_table; |
| 591 | /* This buffer's syntax table. */ |
| 592 | Lisp_Object syntax_table; |
| 593 | /* This buffer's category table. */ |
| 594 | Lisp_Object category_table; |
| 595 | |
| 596 | /* Values of several buffer-local variables. */ |
| 597 | /* tab-width is buffer-local so that redisplay can find it |
| 598 | in buffers that are not current. */ |
| 599 | Lisp_Object case_fold_search; |
| 600 | Lisp_Object tab_width; |
| 601 | Lisp_Object fill_column; |
| 602 | Lisp_Object left_margin; |
| 603 | /* Function to call when insert space past fill column. */ |
| 604 | Lisp_Object auto_fill_function; |
| 605 | /* nil: text, t: binary. |
| 606 | This value is meaningful only on certain operating systems. */ |
| 607 | /* Actually, we don't need this flag any more because end-of-line |
| 608 | is handled correctly according to the buffer-file-coding-system |
| 609 | of the buffer. Just keeping it for backward compatibility. */ |
| 610 | Lisp_Object buffer_file_type; |
| 611 | |
| 612 | /* Case table for case-conversion in this buffer. |
| 613 | This char-table maps each char into its lower-case version. */ |
| 614 | Lisp_Object downcase_table; |
| 615 | /* Char-table mapping each char to its upper-case version. */ |
| 616 | Lisp_Object upcase_table; |
| 617 | /* Char-table for conversion for case-folding search. */ |
| 618 | Lisp_Object case_canon_table; |
| 619 | /* Char-table of equivalences for case-folding search. */ |
| 620 | Lisp_Object case_eqv_table; |
| 621 | |
| 622 | /* Non-nil means do not display continuation lines. */ |
| 623 | Lisp_Object truncate_lines; |
| 624 | /* Non-nil means display ctl chars with uparrow. */ |
| 625 | Lisp_Object ctl_arrow; |
| 626 | /* Non-nil means display text from right to left. */ |
| 627 | Lisp_Object direction_reversed; |
| 628 | /* Non-nil means do selective display; |
| 629 | see doc string in syms_of_buffer (buffer.c) for details. */ |
| 630 | Lisp_Object selective_display; |
| 631 | #ifndef old |
| 632 | /* Non-nil means show ... at end of line followed by invisible lines. */ |
| 633 | Lisp_Object selective_display_ellipses; |
| 634 | #endif |
| 635 | /* Alist of (FUNCTION . STRING) for each minor mode enabled in buffer. */ |
| 636 | Lisp_Object minor_modes; |
| 637 | /* t if "self-insertion" should overwrite; `binary' if it should also |
| 638 | overwrite newlines and tabs - for editing executables and the like. */ |
| 639 | Lisp_Object overwrite_mode; |
| 640 | /* non-nil means abbrev mode is on. Expand abbrevs automatically. */ |
| 641 | Lisp_Object abbrev_mode; |
| 642 | /* Display table to use for text in this buffer. */ |
| 643 | Lisp_Object display_table; |
| 644 | /* t means the mark and region are currently active. */ |
| 645 | Lisp_Object mark_active; |
| 646 | |
| 647 | /* List of overlays that end at or before the current center, |
| 648 | in order of end-position. */ |
| 649 | Lisp_Object overlays_before; |
| 650 | |
| 651 | /* List of overlays that end after the current center, |
| 652 | in order of start-position. */ |
| 653 | Lisp_Object overlays_after; |
| 654 | |
| 655 | /* Position where the overlay lists are centered. */ |
| 656 | Lisp_Object overlay_center; |
| 657 | |
| 658 | /* Non-nil means the buffer contents are regarded as multi-byte |
| 659 | form of characters, not a binary code. */ |
| 660 | Lisp_Object enable_multibyte_characters; |
| 661 | |
| 662 | /* Coding system to be used for encoding the buffer contents on |
| 663 | saving. */ |
| 664 | Lisp_Object buffer_file_coding_system; |
| 665 | |
| 666 | /* List of symbols naming the file format used for visited file. */ |
| 667 | Lisp_Object file_format; |
| 668 | |
| 669 | /* True if the newline position cache and width run cache are |
| 670 | enabled. See search.c and indent.c. */ |
| 671 | Lisp_Object cache_long_line_scans; |
| 672 | |
| 673 | /* If the width run cache is enabled, this table contains the |
| 674 | character widths width_run_cache (see above) assumes. When we |
| 675 | do a thorough redisplay, we compare this against the buffer's |
| 676 | current display table to see whether the display table has |
| 677 | affected the widths of any characters. If it has, we |
| 678 | invalidate the width run cache, and re-initialize width_table. */ |
| 679 | Lisp_Object width_table; |
| 680 | |
| 681 | /* In an indirect buffer, or a buffer that is the base of an |
| 682 | indirect buffer, this holds a marker that records |
| 683 | PT for this buffer when the buffer is not current. */ |
| 684 | Lisp_Object pt_marker; |
| 685 | |
| 686 | /* In an indirect buffer, or a buffer that is the base of an |
| 687 | indirect buffer, this holds a marker that records |
| 688 | BEGV for this buffer when the buffer is not current. */ |
| 689 | Lisp_Object begv_marker; |
| 690 | |
| 691 | /* In an indirect buffer, or a buffer that is the base of an |
| 692 | indirect buffer, this holds a marker that records |
| 693 | ZV for this buffer when the buffer is not current. */ |
| 694 | Lisp_Object zv_marker; |
| 695 | |
| 696 | /* This holds the point value before the last scroll operation. |
| 697 | Explicitly setting point sets this to nil. */ |
| 698 | Lisp_Object point_before_scroll; |
| 699 | |
| 700 | /* Truename of the visited file, or nil. */ |
| 701 | Lisp_Object file_truename; |
| 702 | |
| 703 | /* Invisibility spec of this buffer. |
| 704 | t => any non-nil `invisible' property means invisible. |
| 705 | A list => `invisible' property means invisible |
| 706 | if it is memq in that list. */ |
| 707 | Lisp_Object invisibility_spec; |
| 708 | |
| 709 | /* This is the last window that was selected with this buffer in it, |
| 710 | or nil if that window no longer displays this buffer. */ |
| 711 | Lisp_Object last_selected_window; |
| 712 | |
| 713 | /* Incremented each time the buffer is displayed in a window. */ |
| 714 | Lisp_Object display_count; |
| 715 | |
| 716 | /* Widths of left and right marginal areas for windows displaying |
| 717 | this buffer. */ |
| 718 | Lisp_Object left_margin_width, right_margin_width; |
| 719 | |
| 720 | /* Non-nil means indicate lines not displaying text (in a style |
| 721 | like vi). */ |
| 722 | Lisp_Object indicate_empty_lines; |
| 723 | |
| 724 | /* Time stamp updated each time this buffer is displayed in a window. */ |
| 725 | Lisp_Object display_time; |
| 726 | |
| 727 | /* If scrolling the display because point is below the bottom of a |
| 728 | window showing this buffer, try to choose a window start so |
| 729 | that point ends up this number of lines from the top of the |
| 730 | window. Nil means that scrolling method isn't used. */ |
| 731 | Lisp_Object scroll_up_aggressively; |
| 732 | |
| 733 | /* If scrolling the display because point is above the top of a |
| 734 | window showing this buffer, try to choose a window start so |
| 735 | that point ends up this number of lines from the bottom of the |
| 736 | window. Nil means that scrolling method isn't used. */ |
| 737 | Lisp_Object scroll_down_aggressively; |
| 738 | |
| 739 | /* Desired cursor type in this buffer. See the doc string of |
| 740 | per-buffer variable `cursor-type'. */ |
| 741 | Lisp_Object cursor_type; |
| 742 | |
| 743 | /* An integer > 0 means put that number of pixels below text lines |
| 744 | in the display of this buffer. */ |
| 745 | Lisp_Object extra_line_spacing; |
| 746 | }; |
| 747 | |
| 748 | \f |
| 749 | /* This points to the current buffer. */ |
| 750 | |
| 751 | extern struct buffer *current_buffer; |
| 752 | |
| 753 | /* This structure holds the default values of the buffer-local variables |
| 754 | that have special slots in each buffer. |
| 755 | The default value occupies the same slot in this structure |
| 756 | as an individual buffer's value occupies in that buffer. |
| 757 | Setting the default value also goes through the alist of buffers |
| 758 | and stores into each buffer that does not say it has a local value. */ |
| 759 | |
| 760 | extern struct buffer buffer_defaults; |
| 761 | |
| 762 | /* This structure marks which slots in a buffer have corresponding |
| 763 | default values in buffer_defaults. |
| 764 | Each such slot has a nonzero value in this structure. |
| 765 | The value has only one nonzero bit. |
| 766 | |
| 767 | When a buffer has its own local value for a slot, |
| 768 | the entry for that slot (found in the same slot in this structure) |
| 769 | is turned on in the buffer's local_flags array. |
| 770 | |
| 771 | If a slot in this structure is zero, then even though there may |
| 772 | be a Lisp-level local variable for the slot, it has no default value, |
| 773 | and the corresponding slot in buffer_defaults is not used. */ |
| 774 | |
| 775 | extern struct buffer buffer_local_flags; |
| 776 | |
| 777 | /* For each buffer slot, this points to the Lisp symbol name |
| 778 | for that slot in the current buffer. It is 0 for slots |
| 779 | that don't have such names. */ |
| 780 | |
| 781 | extern struct buffer buffer_local_symbols; |
| 782 | |
| 783 | /* This structure holds the required types for the values in the |
| 784 | buffer-local slots. If a slot contains Qnil, then the |
| 785 | corresponding buffer slot may contain a value of any type. If a |
| 786 | slot contains an integer, then prospective values' tags must be |
| 787 | equal to that integer (except nil is always allowed). |
| 788 | When a tag does not match, the function |
| 789 | buffer_slot_type_mismatch will signal an error. |
| 790 | |
| 791 | If a slot here contains -1, the corresponding variable is read-only. */ |
| 792 | |
| 793 | extern struct buffer buffer_local_types; |
| 794 | \f |
| 795 | extern void reset_buffer P_ ((struct buffer *)); |
| 796 | extern void evaporate_overlays P_ ((int)); |
| 797 | extern int overlays_at P_ ((int, int, Lisp_Object **, int *, int *, int *, int)); |
| 798 | extern int sort_overlays P_ ((Lisp_Object *, int, struct window *)); |
| 799 | extern void recenter_overlay_lists P_ ((struct buffer *, int)); |
| 800 | extern int overlay_strings P_ ((int, struct window *, unsigned char **)); |
| 801 | extern void validate_region P_ ((Lisp_Object *, Lisp_Object *)); |
| 802 | extern void set_buffer_internal P_ ((struct buffer *)); |
| 803 | extern void set_buffer_internal_1 P_ ((struct buffer *)); |
| 804 | extern void set_buffer_temp P_ ((struct buffer *)); |
| 805 | extern void record_buffer P_ ((Lisp_Object)); |
| 806 | extern void buffer_slot_type_mismatch P_ ((int)); |
| 807 | extern void fix_overlays_before P_ ((struct buffer *, int, int)); |
| 808 | extern void mmap_set_vars P_ ((int)); |
| 809 | |
| 810 | EXFUN (Fbuffer_live_p, 1); |
| 811 | EXFUN (Fbuffer_name, 1); |
| 812 | EXFUN (Fget_file_buffer, 1); |
| 813 | EXFUN (Fnext_overlay_change, 1); |
| 814 | EXFUN (Fdelete_overlay, 1); |
| 815 | EXFUN (Fbuffer_local_value, 2); |
| 816 | |
| 817 | /* Functions to call before and after each text change. */ |
| 818 | extern Lisp_Object Vbefore_change_functions; |
| 819 | extern Lisp_Object Vafter_change_functions; |
| 820 | extern Lisp_Object Vfirst_change_hook; |
| 821 | extern Lisp_Object Qbefore_change_functions; |
| 822 | extern Lisp_Object Qafter_change_functions; |
| 823 | extern Lisp_Object Qfirst_change_hook; |
| 824 | |
| 825 | /* If nonzero, all modification hooks are suppressed. */ |
| 826 | extern int inhibit_modification_hooks; |
| 827 | |
| 828 | extern Lisp_Object Vdeactivate_mark; |
| 829 | extern Lisp_Object Vtransient_mark_mode; |
| 830 | \f |
| 831 | /* Overlays */ |
| 832 | |
| 833 | /* 1 if the OV is an overlay object. */ |
| 834 | |
| 835 | #define OVERLAY_VALID(OV) (OVERLAYP (OV)) |
| 836 | |
| 837 | /* Return the marker that stands for where OV starts in the buffer. */ |
| 838 | |
| 839 | #define OVERLAY_START(OV) (XOVERLAY (OV)->start) |
| 840 | |
| 841 | /* Return the marker that stands for where OV ends in the buffer. */ |
| 842 | |
| 843 | #define OVERLAY_END(OV) (XOVERLAY (OV)->end) |
| 844 | |
| 845 | /* Return the plist of overlay OV. */ |
| 846 | |
| 847 | #define OVERLAY_PLIST(OV) XOVERLAY ((OV))->plist |
| 848 | |
| 849 | /* Return the actual buffer position for the marker P. |
| 850 | We assume you know which buffer it's pointing into. */ |
| 851 | |
| 852 | #define OVERLAY_POSITION(P) \ |
| 853 | (GC_MARKERP (P) ? marker_position (P) : (abort (), 0)) |
| 854 | |
| 855 | \f |
| 856 | /*********************************************************************** |
| 857 | Buffer-local Variables |
| 858 | ***********************************************************************/ |
| 859 | |
| 860 | /* Number of per-buffer variables used. */ |
| 861 | |
| 862 | extern int last_per_buffer_idx; |
| 863 | |
| 864 | /* Return the offset in bytes of member VAR of struct buffer |
| 865 | from the start of a buffer structure. */ |
| 866 | |
| 867 | #define PER_BUFFER_VAR_OFFSET(VAR) \ |
| 868 | ((char *) &buffer_local_flags.VAR - (char *) &buffer_local_flags) |
| 869 | |
| 870 | /* Return the index of buffer-local variable VAR. Each per-buffer |
| 871 | variable has an index > 0 associated with it, except when it always |
| 872 | has buffer-local values, in which case the index is -1. If this is |
| 873 | 0, this is a bug and means that the slot of VAR in |
| 874 | buffer_local_flags wasn't intiialized. */ |
| 875 | |
| 876 | #define PER_BUFFER_VAR_IDX(VAR) \ |
| 877 | PER_BUFFER_IDX (PER_BUFFER_VAR_OFFSET (VAR)) |
| 878 | |
| 879 | /* Value is non-zero if the variable with index IDX has a local value |
| 880 | in buffer B. */ |
| 881 | |
| 882 | #define PER_BUFFER_VALUE_P(B, IDX) \ |
| 883 | (((IDX) < 0 || IDX >= last_per_buffer_idx) \ |
| 884 | ? (abort (), 0) \ |
| 885 | : ((B)->local_flags[IDX] != 0)) |
| 886 | |
| 887 | /* Set whether per-buffer variable with index IDX has a buffer-local |
| 888 | value in buffer B. VAL zero means it hasn't. */ |
| 889 | |
| 890 | #define SET_PER_BUFFER_VALUE_P(B, IDX, VAL) \ |
| 891 | do { \ |
| 892 | if ((IDX) < 0 || (IDX) >= last_per_buffer_idx) \ |
| 893 | abort (); \ |
| 894 | (B)->local_flags[IDX] = (VAL); \ |
| 895 | } while (0) |
| 896 | |
| 897 | /* Return the index of the per-buffer variable at offset OFFSET in the |
| 898 | buffer structure. */ |
| 899 | |
| 900 | #define PER_BUFFER_IDX(OFFSET) \ |
| 901 | XINT (*(Lisp_Object *)((OFFSET) + (char *) &buffer_local_flags)) |
| 902 | |
| 903 | /* Return the default value of the per-buffer variable at offset |
| 904 | OFFSET in the buffer structure. */ |
| 905 | |
| 906 | #define PER_BUFFER_DEFAULT(OFFSET) \ |
| 907 | (*(Lisp_Object *)((OFFSET) + (char *) &buffer_defaults)) |
| 908 | |
| 909 | /* Return the buffer-local value of the per-buffer variable at offset |
| 910 | OFFSET in the buffer structure. */ |
| 911 | |
| 912 | #define PER_BUFFER_VALUE(BUFFER, OFFSET) \ |
| 913 | (*(Lisp_Object *)((OFFSET) + (char *) (BUFFER))) |
| 914 | |
| 915 | /* Return the symbol of the per-buffer variable at offset OFFSET in |
| 916 | the buffer structure. */ |
| 917 | |
| 918 | #define PER_BUFFER_SYMBOL(OFFSET) \ |
| 919 | (*(Lisp_Object *)((OFFSET) + (char *) &buffer_local_symbols)) |
| 920 | |
| 921 | /* Return the type of the per-buffer variable at offset OFFSET in the |
| 922 | buffer structure. */ |
| 923 | |
| 924 | #define PER_BUFFER_TYPE(OFFSET) \ |
| 925 | (*(Lisp_Object *)((OFFSET) + (char *) &buffer_local_types)) |