1 /* vi:set ts=8 sts=4 sw=4: 2 * 3 * VIM - Vi IMproved by Bram Moolenaar 4 * 5 * Do ":help uganda" in Vim to read copying and usage conditions. 6 * Do ":help credits" in Vim to see a list of people who contributed. 7 * See README.txt for an overview of the Vim source code. 8 */ 9 10 /* 11 * undo.c: multi level undo facility 12 * 13 * The saved lines are stored in a list of lists (one for each buffer): 14 * 15 * b_u_oldhead------------------------------------------------+ 16 * | 17 * V 18 * +--------------+ +--------------+ +--------------+ 19 * b_u_newhead--->| u_header | | u_header | | u_header | 20 * | uh_next------>| uh_next------>| uh_next---->NULL 21 * NULL<--------uh_prev |<---------uh_prev |<---------uh_prev | 22 * | uh_entry | | uh_entry | | uh_entry | 23 * +--------|-----+ +--------|-----+ +--------|-----+ 24 * | | | 25 * V V V 26 * +--------------+ +--------------+ +--------------+ 27 * | u_entry | | u_entry | | u_entry | 28 * | ue_next | | ue_next | | ue_next | 29 * +--------|-----+ +--------|-----+ +--------|-----+ 30 * | | | 31 * V V V 32 * +--------------+ NULL NULL 33 * | u_entry | 34 * | ue_next | 35 * +--------|-----+ 36 * | 37 * V 38 * etc. 39 * 40 * Each u_entry list contains the information for one undo or redo. 41 * curbuf->b_u_curhead points to the header of the last undo (the next redo), 42 * or is NULL if nothing has been undone. 43 * 44 * All data is allocated with U_ALLOC_LINE(), it will be freed as soon as the 45 * buffer is unloaded. 46 */ 47 48 #include "vim.h" 49 50 /* See below: use malloc()/free() for memory management. */ 51 #define U_USE_MALLOC 1 52 53 static u_entry_T *u_get_headentry __ARGS((void)); 54 static void u_getbot __ARGS((void)); 55 static int u_savecommon __ARGS((linenr_T, linenr_T, linenr_T)); 56 static void u_doit __ARGS((int count)); 57 static void u_undoredo __ARGS((void)); 58 static void u_undo_end __ARGS((void)); 59 static void u_freelist __ARGS((buf_T *buf, struct u_header *)); 60 static void u_freeentry __ARGS((u_entry_T *, long)); 61 62 #ifdef U_USE_MALLOC 63 # define U_FREE_LINE(ptr) vim_free(ptr) 64 # define U_ALLOC_LINE(size) lalloc((long_u)((size) + 1), FALSE) 65 #else 66 static void u_free_line __ARGS((char_u *ptr, int keep)); 67 static char_u *u_alloc_line __ARGS((unsigned size)); 68 # define U_FREE_LINE(ptr) u_free_line((ptr), FALSE) 69 # define U_ALLOC_LINE(size) u_alloc_line(size) 70 #endif 71 static char_u *u_save_line __ARGS((linenr_T)); 72 73 static long u_newcount, u_oldcount; 74 75 /* 76 * When 'u' flag included in 'cpoptions', we behave like vi. Need to remember 77 * the action that "u" should do. 78 */ 79 static int undo_undoes = FALSE; 80 81 /* 82 * Save the current line for both the "u" and "U" command. 83 * Returns OK or FAIL. 84 */ 85 int 86 u_save_cursor() 87 { 88 return (u_save((linenr_T)(curwin->w_cursor.lnum - 1), 89 (linenr_T)(curwin->w_cursor.lnum + 1))); 90 } 91 92 /* 93 * Save the lines between "top" and "bot" for both the "u" and "U" command. 94 * "top" may be 0 and bot may be curbuf->b_ml.ml_line_count + 1. 95 * Returns FAIL when lines could not be saved, OK otherwise. 96 */ 97 int 98 u_save(top, bot) 99 linenr_T top, bot; 100 { 101 if (undo_off) 102 return OK; 103 104 if (top > curbuf->b_ml.ml_line_count || 105 top >= bot || bot > curbuf->b_ml.ml_line_count + 1) 106 return FALSE; /* rely on caller to do error messages */ 107 108 if (top + 2 == bot) 109 u_saveline((linenr_T)(top + 1)); 110 111 return (u_savecommon(top, bot, (linenr_T)0)); 112 } 113 114 /* 115 * save the line "lnum" (used by ":s" and "~" command) 116 * The line is replaced, so the new bottom line is lnum + 1. 117 */ 118 int 119 u_savesub(lnum) 120 linenr_T lnum; 121 { 122 if (undo_off) 123 return OK; 124 125 return (u_savecommon(lnum - 1, lnum + 1, lnum + 1)); 126 } 127 128 /* 129 * a new line is inserted before line "lnum" (used by :s command) 130 * The line is inserted, so the new bottom line is lnum + 1. 131 */ 132 int 133 u_inssub(lnum) 134 linenr_T lnum; 135 { 136 if (undo_off) 137 return OK; 138 139 return (u_savecommon(lnum - 1, lnum, lnum + 1)); 140 } 141 142 /* 143 * save the lines "lnum" - "lnum" + nlines (used by delete command) 144 * The lines are deleted, so the new bottom line is lnum, unless the buffer 145 * becomes empty. 146 */ 147 int 148 u_savedel(lnum, nlines) 149 linenr_T lnum; 150 long nlines; 151 { 152 if (undo_off) 153 return OK; 154 155 return (u_savecommon(lnum - 1, lnum + nlines, 156 nlines == curbuf->b_ml.ml_line_count ? 2 : lnum)); 157 } 158 159 static int 160 u_savecommon(top, bot, newbot) 161 linenr_T top, bot; 162 linenr_T newbot; 163 { 164 linenr_T lnum; 165 long i; 166 struct u_header *uhp; 167 u_entry_T *uep; 168 u_entry_T *prev_uep; 169 long size; 170 171 /* 172 * Don't allow changes when 'modifiable' is off. Letting the 173 * undo fail is a crude way to make all change commands fail. 174 */ 175 if (!curbuf->b_p_ma) 176 { 177 EMSG(_(e_modifiable)); 178 return FAIL; 179 } 180 181 #ifdef HAVE_SANDBOX 182 /* 183 * In the sandbox it's not allowed to change the text. Letting the 184 * undo fail is a crude way to make all change commands fail. 185 */ 186 if (sandbox != 0) 187 { 188 EMSG(_(e_sandbox)); 189 return FAIL; 190 } 191 #endif 192 193 #ifdef FEAT_NETBEANS_INTG 194 /* 195 * Netbeans defines areas that cannot be modified. Bail out here when 196 * trying to change text in a guarded area. 197 */ 198 if (usingNetbeans) 199 { 200 if (netbeans_is_guarded(top, bot)) 201 { 202 EMSG(_(e_guarded)); 203 return FAIL; 204 } 205 if (curbuf->b_p_ro) 206 { 207 EMSG(_(e_nbreadonly)); 208 return FAIL; 209 } 210 } 211 #endif 212 213 #ifdef FEAT_AUTOCMD 214 /* 215 * Saving text for undo means we are going to make a change. Give a 216 * warning for a read-only file before making the change, so that the 217 * FileChangedRO event can replace the buffer with a read-write version 218 * (e.g., obtained from a source control system). 219 */ 220 change_warning(0); 221 #endif 222 223 size = bot - top - 1; 224 225 /* 226 * if curbuf->b_u_synced == TRUE make a new header 227 */ 228 if (curbuf->b_u_synced) 229 { 230 #ifdef FEAT_JUMPLIST 231 /* Need to create new entry in b_changelist. */ 232 curbuf->b_new_change = TRUE; 233 #endif 234 235 /* 236 * if we undid more than we redid, free the entry lists before and 237 * including curbuf->b_u_curhead 238 */ 239 while (curbuf->b_u_curhead != NULL) 240 u_freelist(curbuf, curbuf->b_u_newhead); 241 242 /* 243 * free headers to keep the size right 244 */ 245 while (curbuf->b_u_numhead > p_ul && curbuf->b_u_oldhead != NULL) 246 u_freelist(curbuf, curbuf->b_u_oldhead); 247 248 if (p_ul < 0) /* no undo at all */ 249 { 250 curbuf->b_u_synced = FALSE; 251 return OK; 252 } 253 254 /* 255 * make a new header entry 256 */ 257 uhp = (struct u_header *)U_ALLOC_LINE((unsigned) 258 sizeof(struct u_header)); 259 if (uhp == NULL) 260 goto nomem; 261 uhp->uh_prev = NULL; 262 uhp->uh_next = curbuf->b_u_newhead; 263 if (curbuf->b_u_newhead != NULL) 264 curbuf->b_u_newhead->uh_prev = uhp; 265 uhp->uh_entry = NULL; 266 uhp->uh_getbot_entry = NULL; 267 uhp->uh_cursor = curwin->w_cursor; /* save cursor pos. for undo */ 268 #ifdef FEAT_VIRTUALEDIT 269 if (virtual_active() && curwin->w_cursor.coladd > 0) 270 uhp->uh_cursor_vcol = getviscol(); 271 else 272 uhp->uh_cursor_vcol = -1; 273 #endif 274 275 /* save changed and buffer empty flag for undo */ 276 uhp->uh_flags = (curbuf->b_changed ? UH_CHANGED : 0) + 277 ((curbuf->b_ml.ml_flags & ML_EMPTY) ? UH_EMPTYBUF : 0); 278 279 /* save named marks for undo */ 280 mch_memmove(uhp->uh_namedm, curbuf->b_namedm, sizeof(pos_T) * NMARKS); 281 curbuf->b_u_newhead = uhp; 282 if (curbuf->b_u_oldhead == NULL) 283 curbuf->b_u_oldhead = uhp; 284 ++curbuf->b_u_numhead; 285 } 286 else 287 { 288 if (p_ul < 0) /* no undo at all */ 289 return OK; 290 291 /* 292 * When saving a single line, and it has been saved just before, it 293 * doesn't make sense saving it again. Saves a lot of memory when 294 * making lots of changes inside the same line. 295 * This is only possible if the previous change didn't increase or 296 * decrease the number of lines. 297 * Check the ten last changes. More doesn't make sense and takes too 298 * long. 299 */ 300 if (size == 1) 301 { 302 uep = u_get_headentry(); 303 prev_uep = NULL; 304 for (i = 0; i < 10; ++i) 305 { 306 if (uep == NULL) 307 break; 308 309 /* If lines have been inserted/deleted we give up. 310 * Also when the line was included in a multi-line save. */ 311 if ((curbuf->b_u_newhead->uh_getbot_entry != uep 312 ? (uep->ue_top + uep->ue_size + 1 313 != (uep->ue_bot == 0 314 ? curbuf->b_ml.ml_line_count + 1 315 : uep->ue_bot)) 316 : uep->ue_lcount != curbuf->b_ml.ml_line_count) 317 || (uep->ue_size > 1 318 && top >= uep->ue_top 319 && top + 2 <= uep->ue_top + uep->ue_size + 1)) 320 break; 321 322 /* If it's the same line we can skip saving it again. */ 323 if (uep->ue_size == 1 && uep->ue_top == top) 324 { 325 if (i > 0) 326 { 327 /* It's not the last entry: get ue_bot for the last 328 * entry now. Following deleted/inserted lines go to 329 * the re-used entry. */ 330 u_getbot(); 331 curbuf->b_u_synced = FALSE; 332 333 /* Move the found entry to become the last entry. The 334 * order of undo/redo doesn't matter for the entries 335 * we move it over, since they don't change the line 336 * count and don't include this line. It does matter 337 * for the found entry if the line count is changed by 338 * the executed command. */ 339 prev_uep->ue_next = uep->ue_next; 340 uep->ue_next = curbuf->b_u_newhead->uh_entry; 341 curbuf->b_u_newhead->uh_entry = uep; 342 } 343 344 /* The executed command may change the line count. */ 345 if (newbot != 0) 346 uep->ue_bot = newbot; 347 else if (bot > curbuf->b_ml.ml_line_count) 348 uep->ue_bot = 0; 349 else 350 { 351 uep->ue_lcount = curbuf->b_ml.ml_line_count; 352 curbuf->b_u_newhead->uh_getbot_entry = uep; 353 } 354 return OK; 355 } 356 prev_uep = uep; 357 uep = uep->ue_next; 358 } 359 } 360 361 /* find line number for ue_bot for previous u_save() */ 362 u_getbot(); 363 } 364 365 #if !defined(UNIX) && !defined(DJGPP) && !defined(WIN32) && !defined(__EMX__) 366 /* 367 * With Amiga and MSDOS 16 bit we can't handle big undo's, because 368 * then u_alloc_line would have to allocate a block larger than 32K 369 */ 370 if (size >= 8000) 371 goto nomem; 372 #endif 373 374 /* 375 * add lines in front of entry list 376 */ 377 uep = (u_entry_T *)U_ALLOC_LINE((unsigned)sizeof(u_entry_T)); 378 if (uep == NULL) 379 goto nomem; 380 381 uep->ue_size = size; 382 uep->ue_top = top; 383 if (newbot != 0) 384 uep->ue_bot = newbot; 385 /* 386 * Use 0 for ue_bot if bot is below last line. 387 * Otherwise we have to compute ue_bot later. 388 */ 389 else if (bot > curbuf->b_ml.ml_line_count) 390 uep->ue_bot = 0; 391 else 392 { 393 uep->ue_lcount = curbuf->b_ml.ml_line_count; 394 curbuf->b_u_newhead->uh_getbot_entry = uep; 395 } 396 397 if (size > 0) 398 { 399 if ((uep->ue_array = (char_u **)U_ALLOC_LINE( 400 (unsigned)(sizeof(char_u *) * size))) == NULL) 401 { 402 u_freeentry(uep, 0L); 403 goto nomem; 404 } 405 for (i = 0, lnum = top + 1; i < size; ++i) 406 { 407 fast_breakcheck(); 408 if (got_int) 409 { 410 u_freeentry(uep, i); 411 return FAIL; 412 } 413 if ((uep->ue_array[i] = u_save_line(lnum++)) == NULL) 414 { 415 u_freeentry(uep, i); 416 goto nomem; 417 } 418 } 419 } 420 else 421 uep->ue_array = NULL; 422 uep->ue_next = curbuf->b_u_newhead->uh_entry; 423 curbuf->b_u_newhead->uh_entry = uep; 424 curbuf->b_u_synced = FALSE; 425 undo_undoes = FALSE; 426 427 return OK; 428 429 nomem: 430 msg_silent = 0; /* must display the prompt */ 431 if (ask_yesno((char_u *)_("No undo possible; continue anyway"), TRUE) 432 == 'y') 433 { 434 undo_off = TRUE; /* will be reset when character typed */ 435 return OK; 436 } 437 do_outofmem_msg((long_u)0); 438 return FAIL; 439 } 440 441 /* 442 * If 'cpoptions' contains 'u': Undo the previous undo or redo (vi compatible). 443 * If 'cpoptions' does not contain 'u': Always undo. 444 */ 445 void 446 u_undo(count) 447 int count; 448 { 449 /* 450 * If we get an undo command while executing a macro, we behave like the 451 * original vi. If this happens twice in one macro the result will not 452 * be compatible. 453 */ 454 if (curbuf->b_u_synced == FALSE) 455 { 456 u_sync(); 457 count = 1; 458 } 459 460 if (vim_strchr(p_cpo, CPO_UNDO) == NULL) 461 undo_undoes = TRUE; 462 else 463 undo_undoes = !undo_undoes; 464 u_doit(count); 465 } 466 467 /* 468 * If 'cpoptions' contains 'u': Repeat the previous undo or redo. 469 * If 'cpoptions' does not contain 'u': Always redo. 470 */ 471 void 472 u_redo(count) 473 int count; 474 { 475 if (vim_strchr(p_cpo, CPO_UNDO) == NULL) 476 undo_undoes = FALSE; 477 u_doit(count); 478 } 479 480 /* 481 * Undo or redo, depending on 'undo_undoes', 'count' times. 482 */ 483 static void 484 u_doit(count) 485 int count; 486 { 487 /* Don't allow changes when 'modifiable' is off. */ 488 if (!curbuf->b_p_ma) 489 { 490 EMSG(_(e_modifiable)); 491 return; 492 } 493 #ifdef HAVE_SANDBOX 494 /* In the sandbox it's not allowed to change the text. */ 495 if (sandbox != 0) 496 { 497 EMSG(_(e_sandbox)); 498 return; 499 } 500 #endif 501 502 u_newcount = 0; 503 u_oldcount = 0; 504 if (curbuf->b_ml.ml_flags & ML_EMPTY) 505 u_oldcount = -1; 506 while (count--) 507 { 508 if (undo_undoes) 509 { 510 if (curbuf->b_u_curhead == NULL) /* first undo */ 511 curbuf->b_u_curhead = curbuf->b_u_newhead; 512 else if (p_ul > 0) /* multi level undo */ 513 /* get next undo */ 514 curbuf->b_u_curhead = curbuf->b_u_curhead->uh_next; 515 /* nothing to undo */ 516 if (curbuf->b_u_numhead == 0 || curbuf->b_u_curhead == NULL) 517 { 518 /* stick curbuf->b_u_curhead at end */ 519 curbuf->b_u_curhead = curbuf->b_u_oldhead; 520 beep_flush(); 521 break; 522 } 523 524 u_undoredo(); 525 } 526 else 527 { 528 if (curbuf->b_u_curhead == NULL || p_ul <= 0) 529 { 530 beep_flush(); /* nothing to redo */ 531 break; 532 } 533 534 u_undoredo(); 535 /* advance for next redo */ 536 curbuf->b_u_curhead = curbuf->b_u_curhead->uh_prev; 537 } 538 } 539 if (curbuf->b_ml.ml_flags & ML_EMPTY) 540 --u_newcount; 541 u_undo_end(); 542 } 543 544 /* 545 * u_undoredo: common code for undo and redo 546 * 547 * The lines in the file are replaced by the lines in the entry list at 548 * curbuf->b_u_curhead. The replaced lines in the file are saved in the entry 549 * list for the next undo/redo. 550 */ 551 static void 552 u_undoredo() 553 { 554 char_u **newarray = NULL; 555 linenr_T oldsize; 556 linenr_T newsize; 557 linenr_T top, bot; 558 linenr_T lnum; 559 linenr_T newlnum = MAXLNUM; 560 long i; 561 u_entry_T *uep, *nuep; 562 u_entry_T *newlist = NULL; 563 int old_flags; 564 int new_flags; 565 pos_T namedm[NMARKS]; 566 int empty_buffer; /* buffer became empty */ 567 568 old_flags = curbuf->b_u_curhead->uh_flags; 569 new_flags = (curbuf->b_changed ? UH_CHANGED : 0) + 570 ((curbuf->b_ml.ml_flags & ML_EMPTY) ? UH_EMPTYBUF : 0); 571 setpcmark(); 572 573 /* 574 * save marks before undo/redo 575 */ 576 mch_memmove(namedm, curbuf->b_namedm, sizeof(pos_T) * NMARKS); 577 curbuf->b_op_start.lnum = curbuf->b_ml.ml_line_count; 578 curbuf->b_op_start.col = 0; 579 curbuf->b_op_end.lnum = 0; 580 curbuf->b_op_end.col = 0; 581 582 for (uep = curbuf->b_u_curhead->uh_entry; uep != NULL; uep = nuep) 583 { 584 top = uep->ue_top; 585 bot = uep->ue_bot; 586 if (bot == 0) 587 bot = curbuf->b_ml.ml_line_count + 1; 588 if (top > curbuf->b_ml.ml_line_count || top >= bot 589 || bot > curbuf->b_ml.ml_line_count + 1) 590 { 591 EMSG(_("E438: u_undo: line numbers wrong")); 592 changed(); /* don't want UNCHANGED now */ 593 return; 594 } 595 596 oldsize = bot - top - 1; /* number of lines before undo */ 597 newsize = uep->ue_size; /* number of lines after undo */ 598 599 if (top < newlnum) 600 { 601 /* If the saved cursor is somewhere in this undo block, move it to 602 * the remembered position. Makes "gwap" put the cursor back 603 * where it was. */ 604 lnum = curbuf->b_u_curhead->uh_cursor.lnum; 605 if (lnum >= top && lnum <= top + newsize + 1) 606 { 607 curwin->w_cursor = curbuf->b_u_curhead->uh_cursor; 608 newlnum = curwin->w_cursor.lnum - 1; 609 } 610 else 611 { 612 /* Use the first line that actually changed. Avoids that 613 * undoing auto-formatting puts the cursor in the previous 614 * line. */ 615 for (i = 0; i < newsize && i < oldsize; ++i) 616 if (STRCMP(uep->ue_array[i], ml_get(top + 1 + i)) != 0) 617 break; 618 if (i == newsize && newlnum == MAXLNUM && uep->ue_next == NULL) 619 { 620 newlnum = top; 621 curwin->w_cursor.lnum = newlnum + 1; 622 } 623 else if (i < newsize) 624 { 625 newlnum = top + i; 626 curwin->w_cursor.lnum = newlnum + 1; 627 } 628 } 629 } 630 631 empty_buffer = FALSE; 632 633 /* delete the lines between top and bot and save them in newarray */ 634 if (oldsize > 0) 635 { 636 if ((newarray = (char_u **)U_ALLOC_LINE( 637 (unsigned)(sizeof(char_u *) * oldsize))) == NULL) 638 { 639 do_outofmem_msg((long_u)(sizeof(char_u *) * oldsize)); 640 /* 641 * We have messed up the entry list, repair is impossible. 642 * we have to free the rest of the list. 643 */ 644 while (uep != NULL) 645 { 646 nuep = uep->ue_next; 647 u_freeentry(uep, uep->ue_size); 648 uep = nuep; 649 } 650 break; 651 } 652 /* delete backwards, it goes faster in most cases */ 653 for (lnum = bot - 1, i = oldsize; --i >= 0; --lnum) 654 { 655 /* what can we do when we run out of memory? */ 656 if ((newarray[i] = u_save_line(lnum)) == NULL) 657 do_outofmem_msg((long_u)0); 658 /* remember we deleted the last line in the buffer, and a 659 * dummy empty line will be inserted */ 660 if (curbuf->b_ml.ml_line_count == 1) 661 empty_buffer = TRUE; 662 ml_delete(lnum, FALSE); 663 } 664 } 665 else 666 newarray = NULL; 667 668 /* insert the lines in u_array between top and bot */ 669 if (newsize) 670 { 671 for (lnum = top, i = 0; i < newsize; ++i, ++lnum) 672 { 673 /* 674 * If the file is empty, there is an empty line 1 that we 675 * should get rid of, by replacing it with the new line 676 */ 677 if (empty_buffer && lnum == 0) 678 ml_replace((linenr_T)1, uep->ue_array[i], TRUE); 679 else 680 ml_append(lnum, uep->ue_array[i], (colnr_T)0, FALSE); 681 U_FREE_LINE(uep->ue_array[i]); 682 } 683 U_FREE_LINE((char_u *)uep->ue_array); 684 } 685 686 /* adjust marks */ 687 if (oldsize != newsize) 688 { 689 mark_adjust(top + 1, top + oldsize, (long)MAXLNUM, 690 (long)newsize - (long)oldsize); 691 if (curbuf->b_op_start.lnum > top + oldsize) 692 curbuf->b_op_start.lnum += newsize - oldsize; 693 if (curbuf->b_op_end.lnum > top + oldsize) 694 curbuf->b_op_end.lnum += newsize - oldsize; 695 } 696 697 changed_lines(top + 1, 0, bot, newsize - oldsize); 698 699 /* set '[ and '] mark */ 700 if (top + 1 < curbuf->b_op_start.lnum) 701 curbuf->b_op_start.lnum = top + 1; 702 if (newsize == 0 && top + 1 > curbuf->b_op_end.lnum) 703 curbuf->b_op_end.lnum = top + 1; 704 else if (top + newsize > curbuf->b_op_end.lnum) 705 curbuf->b_op_end.lnum = top + newsize; 706 707 u_newcount += newsize; 708 u_oldcount += oldsize; 709 uep->ue_size = oldsize; 710 uep->ue_array = newarray; 711 uep->ue_bot = top + newsize + 1; 712 713 /* 714 * insert this entry in front of the new entry list 715 */ 716 nuep = uep->ue_next; 717 uep->ue_next = newlist; 718 newlist = uep; 719 } 720 721 curbuf->b_u_curhead->uh_entry = newlist; 722 curbuf->b_u_curhead->uh_flags = new_flags; 723 if ((old_flags & UH_EMPTYBUF) && bufempty()) 724 curbuf->b_ml.ml_flags |= ML_EMPTY; 725 if (old_flags & UH_CHANGED) 726 changed(); 727 else 728 #ifdef FEAT_NETBEANS_INTG 729 /* per netbeans undo rules, keep it as modified */ 730 if (!isNetbeansModified(curbuf)) 731 #endif 732 unchanged(curbuf, FALSE); 733 734 /* 735 * restore marks from before undo/redo 736 */ 737 for (i = 0; i < NMARKS; ++i) 738 if (curbuf->b_u_curhead->uh_namedm[i].lnum) 739 { 740 curbuf->b_namedm[i] = curbuf->b_u_curhead->uh_namedm[i]; 741 curbuf->b_u_curhead->uh_namedm[i] = namedm[i]; 742 } 743 744 /* 745 * If the cursor is only off by one line, put it at the same position as 746 * before starting the change (for the "o" command). 747 * Otherwise the cursor should go to the first undone line. 748 */ 749 if (curbuf->b_u_curhead->uh_cursor.lnum + 1 == curwin->w_cursor.lnum 750 && curwin->w_cursor.lnum > 1) 751 --curwin->w_cursor.lnum; 752 if (curbuf->b_u_curhead->uh_cursor.lnum == curwin->w_cursor.lnum) 753 { 754 curwin->w_cursor.col = curbuf->b_u_curhead->uh_cursor.col; 755 #ifdef FEAT_VIRTUALEDIT 756 if (virtual_active() && curbuf->b_u_curhead->uh_cursor_vcol >= 0) 757 coladvance((colnr_T)curbuf->b_u_curhead->uh_cursor_vcol); 758 else 759 curwin->w_cursor.coladd = 0; 760 #endif 761 } 762 else if (curwin->w_cursor.lnum <= curbuf->b_ml.ml_line_count) 763 beginline(BL_SOL | BL_FIX); 764 else 765 { 766 /* We get here with the current cursor line being past the end (eg 767 * after adding lines at the end of the file, and then undoing it). 768 * check_cursor() will move the cursor to the last line. Move it to 769 * the first column here. */ 770 curwin->w_cursor.col = 0; 771 #ifdef FEAT_VIRTUALEDIT 772 curwin->w_cursor.coladd = 0; 773 #endif 774 } 775 776 /* Make sure the cursor is on an existing line and column. */ 777 check_cursor(); 778 } 779 780 /* 781 * If we deleted or added lines, report the number of less/more lines. 782 * Otherwise, report the number of changes (this may be incorrect 783 * in some cases, but it's better than nothing). 784 */ 785 static void 786 u_undo_end() 787 { 788 if ((u_oldcount -= u_newcount) != 0) 789 msgmore(-u_oldcount); 790 else if (u_newcount > p_report) 791 { 792 if (u_newcount == 1) 793 MSG(_("1 change")); 794 else 795 smsg((char_u *)_("%ld changes"), u_newcount); 796 } 797 #ifdef FEAT_FOLDING 798 if ((fdo_flags & FDO_UNDO) && KeyTyped) 799 foldOpenCursor(); 800 #endif 801 } 802 803 /* 804 * u_sync: stop adding to the current entry list 805 */ 806 void 807 u_sync() 808 { 809 if (curbuf->b_u_synced) 810 return; /* already synced */ 811 #if defined(FEAT_XIM) && defined(FEAT_GUI_GTK) 812 if (im_is_preediting()) 813 return; /* XIM is busy, don't break an undo sequence */ 814 #endif 815 if (p_ul < 0) 816 curbuf->b_u_synced = TRUE; /* no entries, nothing to do */ 817 else 818 { 819 u_getbot(); /* compute ue_bot of previous u_save */ 820 curbuf->b_u_curhead = NULL; 821 } 822 } 823 824 /* 825 * Called after writing the file and setting b_changed to FALSE. 826 * Now an undo means that the buffer is modified. 827 */ 828 void 829 u_unchanged(buf) 830 buf_T *buf; 831 { 832 struct u_header *uh; 833 834 for (uh = buf->b_u_newhead; uh; uh = uh->uh_next) 835 uh->uh_flags |= UH_CHANGED; 836 buf->b_did_warn = FALSE; 837 } 838 839 /* 840 * Get pointer to last added entry. 841 * If it's not valid, give an error message and return NULL. 842 */ 843 static u_entry_T * 844 u_get_headentry() 845 { 846 if (curbuf->b_u_newhead == NULL || curbuf->b_u_newhead->uh_entry == NULL) 847 { 848 EMSG(_("E439: undo list corrupt")); 849 return NULL; 850 } 851 return curbuf->b_u_newhead->uh_entry; 852 } 853 854 /* 855 * u_getbot(): compute the line number of the previous u_save 856 * It is called only when b_u_synced is FALSE. 857 */ 858 static void 859 u_getbot() 860 { 861 u_entry_T *uep; 862 linenr_T extra; 863 864 uep = u_get_headentry(); /* check for corrupt undo list */ 865 if (uep == NULL) 866 return; 867 868 uep = curbuf->b_u_newhead->uh_getbot_entry; 869 if (uep != NULL) 870 { 871 /* 872 * the new ue_bot is computed from the number of lines that has been 873 * inserted (0 - deleted) since calling u_save. This is equal to the 874 * old line count subtracted from the current line count. 875 */ 876 extra = curbuf->b_ml.ml_line_count - uep->ue_lcount; 877 uep->ue_bot = uep->ue_top + uep->ue_size + 1 + extra; 878 if (uep->ue_bot < 1 || uep->ue_bot > curbuf->b_ml.ml_line_count) 879 { 880 EMSG(_("E440: undo line missing")); 881 uep->ue_bot = uep->ue_top + 1; /* assume all lines deleted, will 882 * get all the old lines back 883 * without deleting the current 884 * ones */ 885 } 886 887 curbuf->b_u_newhead->uh_getbot_entry = NULL; 888 } 889 890 curbuf->b_u_synced = TRUE; 891 } 892 893 /* 894 * u_freelist: free one entry list and adjust the pointers 895 */ 896 static void 897 u_freelist(buf, uhp) 898 buf_T *buf; 899 struct u_header *uhp; 900 { 901 u_entry_T *uep, *nuep; 902 903 for (uep = uhp->uh_entry; uep != NULL; uep = nuep) 904 { 905 nuep = uep->ue_next; 906 u_freeentry(uep, uep->ue_size); 907 } 908 909 if (buf->b_u_curhead == uhp) 910 buf->b_u_curhead = NULL; 911 912 if (uhp->uh_next == NULL) 913 buf->b_u_oldhead = uhp->uh_prev; 914 else 915 uhp->uh_next->uh_prev = uhp->uh_prev; 916 917 if (uhp->uh_prev == NULL) 918 buf->b_u_newhead = uhp->uh_next; 919 else 920 uhp->uh_prev->uh_next = uhp->uh_next; 921 922 U_FREE_LINE((char_u *)uhp); 923 --buf->b_u_numhead; 924 } 925 926 /* 927 * free entry 'uep' and 'n' lines in uep->ue_array[] 928 */ 929 static void 930 u_freeentry(uep, n) 931 u_entry_T *uep; 932 long n; 933 { 934 while (n > 0) 935 U_FREE_LINE(uep->ue_array[--n]); 936 U_FREE_LINE((char_u *)uep->ue_array); 937 U_FREE_LINE((char_u *)uep); 938 } 939 940 /* 941 * invalidate the undo buffer; called when storage has already been released 942 */ 943 void 944 u_clearall(buf) 945 buf_T *buf; 946 { 947 buf->b_u_newhead = buf->b_u_oldhead = buf->b_u_curhead = NULL; 948 buf->b_u_synced = TRUE; 949 buf->b_u_numhead = 0; 950 buf->b_u_line_ptr = NULL; 951 buf->b_u_line_lnum = 0; 952 } 953 954 /* 955 * save the line "lnum" for the "U" command 956 */ 957 void 958 u_saveline(lnum) 959 linenr_T lnum; 960 { 961 if (lnum == curbuf->b_u_line_lnum) /* line is already saved */ 962 return; 963 if (lnum < 1 || lnum > curbuf->b_ml.ml_line_count) /* should never happen */ 964 return; 965 u_clearline(); 966 curbuf->b_u_line_lnum = lnum; 967 if (curwin->w_cursor.lnum == lnum) 968 curbuf->b_u_line_colnr = curwin->w_cursor.col; 969 else 970 curbuf->b_u_line_colnr = 0; 971 if ((curbuf->b_u_line_ptr = u_save_line(lnum)) == NULL) 972 do_outofmem_msg((long_u)0); 973 } 974 975 /* 976 * clear the line saved for the "U" command 977 * (this is used externally for crossing a line while in insert mode) 978 */ 979 void 980 u_clearline() 981 { 982 if (curbuf->b_u_line_ptr != NULL) 983 { 984 U_FREE_LINE(curbuf->b_u_line_ptr); 985 curbuf->b_u_line_ptr = NULL; 986 curbuf->b_u_line_lnum = 0; 987 } 988 } 989 990 /* 991 * Implementation of the "U" command. 992 * Differentiation from vi: "U" can be undone with the next "U". 993 * We also allow the cursor to be in another line. 994 */ 995 void 996 u_undoline() 997 { 998 colnr_T t; 999 char_u *oldp; 1000 1001 if (undo_off) 1002 return; 1003 1004 if (curbuf->b_u_line_ptr == NULL || 1005 curbuf->b_u_line_lnum > curbuf->b_ml.ml_line_count) 1006 { 1007 beep_flush(); 1008 return; 1009 } 1010 /* first save the line for the 'u' command */ 1011 if (u_savecommon(curbuf->b_u_line_lnum - 1, 1012 curbuf->b_u_line_lnum + 1, (linenr_T)0) == FAIL) 1013 return; 1014 oldp = u_save_line(curbuf->b_u_line_lnum); 1015 if (oldp == NULL) 1016 { 1017 do_outofmem_msg((long_u)0); 1018 return; 1019 } 1020 ml_replace(curbuf->b_u_line_lnum, curbuf->b_u_line_ptr, TRUE); 1021 changed_bytes(curbuf->b_u_line_lnum, 0); 1022 U_FREE_LINE(curbuf->b_u_line_ptr); 1023 curbuf->b_u_line_ptr = oldp; 1024 1025 t = curbuf->b_u_line_colnr; 1026 if (curwin->w_cursor.lnum == curbuf->b_u_line_lnum) 1027 curbuf->b_u_line_colnr = curwin->w_cursor.col; 1028 curwin->w_cursor.col = t; 1029 curwin->w_cursor.lnum = curbuf->b_u_line_lnum; 1030 } 1031 1032 /* 1033 * There are two implementations of the memory management for undo: 1034 * 1. Use the standard malloc()/free() functions. 1035 * This should be fast for allocating memory, but when a buffer is 1036 * abandoned every single allocated chunk must be freed, which may be slow. 1037 * 2. Allocate larger blocks of memory and keep track of chunks ourselves. 1038 * This is fast for abandoning, but the use of linked lists is slow for 1039 * finding a free chunk. Esp. when a lot of lines are changed or deleted. 1040 * A bit of profiling showed that the first method is faster, especially when 1041 * making a large number of changes, under the condition that malloc()/free() 1042 * is implemented efficiently. 1043 */ 1044 #ifdef U_USE_MALLOC 1045 /* 1046 * Version of undo memory allocation using malloc()/free() 1047 * 1048 * U_FREE_LINE() and U_ALLOC_LINE() are macros that invoke vim_free() and 1049 * lalloc() directly. 1050 */ 1051 1052 /* 1053 * Free all allocated memory blocks for the buffer 'buf'. 1054 */ 1055 void 1056 u_blockfree(buf) 1057 buf_T *buf; 1058 { 1059 while (buf->b_u_newhead != NULL) 1060 u_freelist(buf, buf->b_u_newhead); 1061 U_FREE_LINE(buf->b_u_line_ptr); 1062 } 1063 1064 #else 1065 /* 1066 * Storage allocation for the undo lines and blocks of the current file. 1067 * Version where Vim keeps track of the available memory. 1068 */ 1069 1070 /* 1071 * Memory is allocated in relatively large blocks. These blocks are linked 1072 * in the allocated block list, headed by curbuf->b_block_head. They are all 1073 * freed when abandoning a file, so we don't have to free every single line. 1074 * The list is kept sorted on memory address. 1075 * block_alloc() allocates a block. 1076 * m_blockfree() frees all blocks. 1077 * 1078 * The available chunks of memory are kept in free chunk lists. There is 1079 * one free list for each block of allocated memory. The list is kept sorted 1080 * on memory address. 1081 * u_alloc_line() gets a chunk from the free lists. 1082 * u_free_line() returns a chunk to the free lists. 1083 * curbuf->b_m_search points to the chunk before the chunk that was 1084 * freed/allocated the last time. 1085 * curbuf->b_mb_current points to the b_head where curbuf->b_m_search 1086 * points into the free list. 1087 * 1088 * 1089 * b_block_head /---> block #1 /---> block #2 1090 * mb_next ---/ mb_next ---/ mb_next ---> NULL 1091 * mb_info mb_info mb_info 1092 * | | | 1093 * V V V 1094 * NULL free chunk #1.1 free chunk #2.1 1095 * | | 1096 * V V 1097 * free chunk #1.2 NULL 1098 * | 1099 * V 1100 * NULL 1101 * 1102 * When a single free chunk list would have been used, it could take a lot 1103 * of time in u_free_line() to find the correct place to insert a chunk in the 1104 * free list. The single free list would become very long when many lines are 1105 * changed (e.g. with :%s/^M$//). 1106 */ 1107 1108 /* 1109 * this blocksize is used when allocating new lines 1110 */ 1111 #define MEMBLOCKSIZE 2044 1112 1113 /* 1114 * The size field contains the size of the chunk, including the size field 1115 * itself. 1116 * 1117 * When the chunk is not in-use it is preceded with the m_info structure. 1118 * The m_next field links it in one of the free chunk lists. 1119 * 1120 * On most unix systems structures have to be longword (32 or 64 bit) aligned. 1121 * On most other systems they are short (16 bit) aligned. 1122 */ 1123 1124 /* the structure definitions are now in structs.h */ 1125 1126 #ifdef ALIGN_LONG 1127 /* size of m_size */ 1128 # define M_OFFSET (sizeof(long_u)) 1129 #else 1130 /* size of m_size */ 1131 # define M_OFFSET (sizeof(short_u)) 1132 #endif 1133 1134 static char_u *u_blockalloc __ARGS((long_u)); 1135 1136 /* 1137 * Allocate a block of memory and link it in the allocated block list. 1138 */ 1139 static char_u * 1140 u_blockalloc(size) 1141 long_u size; 1142 { 1143 mblock_T *p; 1144 mblock_T *mp, *next; 1145 1146 p = (mblock_T *)lalloc(size + sizeof(mblock_T), FALSE); 1147 if (p != NULL) 1148 { 1149 /* Insert the block into the allocated block list, keeping it 1150 sorted on address. */ 1151 for (mp = &curbuf->b_block_head; 1152 (next = mp->mb_next) != NULL && next < p; 1153 mp = next) 1154 ; 1155 p->mb_next = next; /* link in block list */ 1156 p->mb_size = size; 1157 p->mb_maxsize = 0; /* nothing free yet */ 1158 mp->mb_next = p; 1159 p->mb_info.m_next = NULL; /* clear free list */ 1160 p->mb_info.m_size = 0; 1161 curbuf->b_mb_current = p; /* remember current block */ 1162 curbuf->b_m_search = NULL; 1163 p++; /* return usable memory */ 1164 } 1165 return (char_u *)p; 1166 } 1167 1168 /* 1169 * free all allocated memory blocks for the buffer 'buf' 1170 */ 1171 void 1172 u_blockfree(buf) 1173 buf_T *buf; 1174 { 1175 mblock_T *p, *np; 1176 1177 for (p = buf->b_block_head.mb_next; p != NULL; p = np) 1178 { 1179 np = p->mb_next; 1180 vim_free(p); 1181 } 1182 buf->b_block_head.mb_next = NULL; 1183 buf->b_m_search = NULL; 1184 buf->b_mb_current = NULL; 1185 } 1186 1187 /* 1188 * Free a chunk of memory for the current buffer. 1189 * Insert the chunk into the correct free list, keeping it sorted on address. 1190 */ 1191 static void 1192 u_free_line(ptr, keep) 1193 char_u *ptr; 1194 int keep; /* don't free the block when it's empty */ 1195 { 1196 minfo_T *next; 1197 minfo_T *prev, *curr; 1198 minfo_T *mp; 1199 mblock_T *nextb; 1200 mblock_T *prevb; 1201 long_u maxsize; 1202 1203 if (ptr == NULL || ptr == IObuff) 1204 return; /* illegal address can happen in out-of-memory situations */ 1205 1206 mp = (minfo_T *)(ptr - M_OFFSET); 1207 1208 /* find block where chunk could be a part off */ 1209 /* if we change curbuf->b_mb_current, curbuf->b_m_search is set to NULL */ 1210 if (curbuf->b_mb_current == NULL || mp < (minfo_T *)curbuf->b_mb_current) 1211 { 1212 curbuf->b_mb_current = curbuf->b_block_head.mb_next; 1213 curbuf->b_m_search = NULL; 1214 } 1215 if ((nextb = curbuf->b_mb_current->mb_next) != NULL 1216 && (minfo_T *)nextb < mp) 1217 { 1218 curbuf->b_mb_current = nextb; 1219 curbuf->b_m_search = NULL; 1220 } 1221 while ((nextb = curbuf->b_mb_current->mb_next) != NULL 1222 && (minfo_T *)nextb < mp) 1223 curbuf->b_mb_current = nextb; 1224 1225 curr = NULL; 1226 /* 1227 * If mp is smaller than curbuf->b_m_search->m_next go to the start of 1228 * the free list 1229 */ 1230 if (curbuf->b_m_search == NULL || mp < (curbuf->b_m_search->m_next)) 1231 next = &(curbuf->b_mb_current->mb_info); 1232 else 1233 next = curbuf->b_m_search; 1234 /* 1235 * The following loop is executed very often. 1236 * Therefore it has been optimized at the cost of readability. 1237 * Keep it fast! 1238 */ 1239 #ifdef SLOW_BUT_EASY_TO_READ 1240 do 1241 { 1242 prev = curr; 1243 curr = next; 1244 next = next->m_next; 1245 } 1246 while (mp > next && next != NULL); 1247 #else 1248 do /* first, middle, last */ 1249 { 1250 prev = next->m_next; /* curr, next, prev */ 1251 if (prev == NULL || mp <= prev) 1252 { 1253 prev = curr; 1254 curr = next; 1255 next = next->m_next; 1256 break; 1257 } 1258 curr = prev->m_next; /* next, prev, curr */ 1259 if (curr == NULL || mp <= curr) 1260 { 1261 prev = next; 1262 curr = prev->m_next; 1263 next = curr->m_next; 1264 break; 1265 } 1266 next = curr->m_next; /* prev, curr, next */ 1267 } 1268 while (mp > next && next != NULL); 1269 #endif 1270 1271 /* if *mp and *next are concatenated, join them into one chunk */ 1272 if ((char_u *)mp + mp->m_size == (char_u *)next) 1273 { 1274 mp->m_size += next->m_size; 1275 mp->m_next = next->m_next; 1276 } 1277 else 1278 mp->m_next = next; 1279 maxsize = mp->m_size; 1280 1281 /* if *curr and *mp are concatenated, join them */ 1282 if (prev != NULL && (char_u *)curr + curr->m_size == (char_u *)mp) 1283 { 1284 curr->m_size += mp->m_size; 1285 maxsize = curr->m_size; 1286 curr->m_next = mp->m_next; 1287 curbuf->b_m_search = prev; 1288 } 1289 else 1290 { 1291 curr->m_next = mp; 1292 curbuf->b_m_search = curr; /* put curbuf->b_m_search before freed 1293 chunk */ 1294 } 1295 1296 /* 1297 * If the block only containes free memory now, release it. 1298 */ 1299 if (!keep && curbuf->b_mb_current->mb_size 1300 == curbuf->b_mb_current->mb_info.m_next->m_size) 1301 { 1302 /* Find the block before the current one to be able to unlink it from 1303 * the list of blocks. */ 1304 prevb = &curbuf->b_block_head; 1305 for (nextb = prevb->mb_next; nextb != curbuf->b_mb_current; 1306 nextb = nextb->mb_next) 1307 prevb = nextb; 1308 prevb->mb_next = nextb->mb_next; 1309 vim_free(nextb); 1310 curbuf->b_mb_current = NULL; 1311 curbuf->b_m_search = NULL; 1312 } 1313 else if (curbuf->b_mb_current->mb_maxsize < maxsize) 1314 curbuf->b_mb_current->mb_maxsize = maxsize; 1315 } 1316 1317 /* 1318 * Allocate and initialize a new line structure with room for at least 1319 * 'size' characters plus a terminating NUL. 1320 */ 1321 static char_u * 1322 u_alloc_line(size) 1323 unsigned size; 1324 { 1325 minfo_T *mp, *mprev, *mp2; 1326 mblock_T *mbp; 1327 int size_align; 1328 1329 /* 1330 * Add room for size field and trailing NUL byte. 1331 * Adjust for minimal size (must be able to store minfo_T 1332 * plus a trailing NUL, so the chunk can be released again) 1333 */ 1334 size += M_OFFSET + 1; 1335 if (size < sizeof(minfo_T) + 1) 1336 size = sizeof(minfo_T) + 1; 1337 1338 /* 1339 * round size up for alignment 1340 */ 1341 size_align = (size + ALIGN_MASK) & ~ALIGN_MASK; 1342 1343 /* 1344 * If curbuf->b_m_search is NULL (uninitialized free list) start at 1345 * curbuf->b_block_head 1346 */ 1347 if (curbuf->b_mb_current == NULL || curbuf->b_m_search == NULL) 1348 { 1349 curbuf->b_mb_current = &curbuf->b_block_head; 1350 curbuf->b_m_search = &(curbuf->b_block_head.mb_info); 1351 } 1352 1353 /* Search for a block with enough space. */ 1354 mbp = curbuf->b_mb_current; 1355 while (mbp->mb_maxsize < size_align) 1356 { 1357 if (mbp->mb_next != NULL) 1358 mbp = mbp->mb_next; 1359 else 1360 mbp = &curbuf->b_block_head; 1361 if (mbp == curbuf->b_mb_current) 1362 { 1363 int n = (size_align > (MEMBLOCKSIZE / 4) 1364 ? size_align : MEMBLOCKSIZE); 1365 1366 /* Back where we started in block list: need to add a new block 1367 * with enough space. */ 1368 mp = (minfo_T *)u_blockalloc((long_u)n); 1369 if (mp == NULL) 1370 return (NULL); 1371 mp->m_size = n; 1372 u_free_line((char_u *)mp + M_OFFSET, TRUE); 1373 mbp = curbuf->b_mb_current; 1374 break; 1375 } 1376 } 1377 if (mbp != curbuf->b_mb_current) 1378 curbuf->b_m_search = &(mbp->mb_info); 1379 1380 /* In this block find a chunk with enough space. */ 1381 mprev = curbuf->b_m_search; 1382 mp = curbuf->b_m_search->m_next; 1383 for (;;) 1384 { 1385 if (mp == NULL) /* at end of the list */ 1386 mp = &(mbp->mb_info); /* wrap around to begin */ 1387 if (mp->m_size >= size) 1388 break; 1389 if (mp == curbuf->b_m_search) 1390 { 1391 /* back where we started in free chunk list: "cannot happen" */ 1392 EMSG2(_(e_intern2), "u_alloc_line()"); 1393 return NULL; 1394 } 1395 mprev = mp; 1396 mp = mp->m_next; 1397 } 1398 1399 /* when using the largest chunk adjust mb_maxsize */ 1400 if (mp->m_size >= mbp->mb_maxsize) 1401 mbp->mb_maxsize = 0; 1402 1403 /* if the chunk we found is large enough, split it up in two */ 1404 if ((long)mp->m_size - size_align >= (long)(sizeof(minfo_T) + 1)) 1405 { 1406 mp2 = (minfo_T *)((char_u *)mp + size_align); 1407 mp2->m_size = mp->m_size - size_align; 1408 mp2->m_next = mp->m_next; 1409 mprev->m_next = mp2; 1410 mp->m_size = size_align; 1411 } 1412 else /* remove *mp from the free list */ 1413 { 1414 mprev->m_next = mp->m_next; 1415 } 1416 curbuf->b_m_search = mprev; 1417 curbuf->b_mb_current = mbp; 1418 1419 /* If using the largest chunk need to find the new largest chunk */ 1420 if (mbp->mb_maxsize == 0) 1421 for (mp2 = &(mbp->mb_info); mp2 != NULL; mp2 = mp2->m_next) 1422 if (mbp->mb_maxsize < mp2->m_size) 1423 mbp->mb_maxsize = mp2->m_size; 1424 1425 mp = (minfo_T *)((char_u *)mp + M_OFFSET); 1426 *(char_u *)mp = NUL; /* set the first byte to NUL */ 1427 1428 return ((char_u *)mp); 1429 } 1430 #endif 1431 1432 /* 1433 * u_save_line(): allocate memory with u_alloc_line() and copy line 'lnum' 1434 * into it. 1435 */ 1436 static char_u * 1437 u_save_line(lnum) 1438 linenr_T lnum; 1439 { 1440 char_u *src; 1441 char_u *dst; 1442 unsigned len; 1443 1444 src = ml_get(lnum); 1445 len = (unsigned)STRLEN(src); 1446 if ((dst = U_ALLOC_LINE(len)) != NULL) 1447 mch_memmove(dst, src, (size_t)(len + 1)); 1448 return (dst); 1449 } 1450 1451 /* 1452 * Check if the 'modified' flag is set, or 'ff' has changed (only need to 1453 * check the first character, because it can only be "dos", "unix" or "mac"). 1454 * "nofile" and "scratch" type buffers are considered to always be unchanged. 1455 */ 1456 int 1457 bufIsChanged(buf) 1458 buf_T *buf; 1459 { 1460 return 1461 #ifdef FEAT_QUICKFIX 1462 !bt_dontwrite(buf) && 1463 #endif 1464 (buf->b_changed || file_ff_differs(buf)); 1465 } 1466 1467 int 1468 curbufIsChanged() 1469 { 1470 return 1471 #ifdef FEAT_QUICKFIX 1472 !bt_dontwrite(curbuf) && 1473 #endif 1474 (curbuf->b_changed || file_ff_differs(curbuf)); 1475 } 1476