/* vi:set ts=8 sts=4 sw=4: * * VIM - Vi IMproved by Bram Moolenaar * * Do ":help uganda" in Vim to read copying and usage conditions. * Do ":help credits" in Vim to see a list of people who contributed. * See README.txt for an overview of the Vim source code. */ /* * undo.c: multi level undo facility * * The saved lines are stored in a list of lists (one for each buffer): * * b_u_oldhead------------------------------------------------+ * | * V * +--------------+ +--------------+ +--------------+ * b_u_newhead--->| u_header | | u_header | | u_header | * | uh_next------>| uh_next------>| uh_next---->NULL * NULL<--------uh_prev |<---------uh_prev |<---------uh_prev | * | uh_entry | | uh_entry | | uh_entry | * +--------|-----+ +--------|-----+ +--------|-----+ * | | | * V V V * +--------------+ +--------------+ +--------------+ * | u_entry | | u_entry | | u_entry | * | ue_next | | ue_next | | ue_next | * +--------|-----+ +--------|-----+ +--------|-----+ * | | | * V V V * +--------------+ NULL NULL * | u_entry | * | ue_next | * +--------|-----+ * | * V * etc. * * Each u_entry list contains the information for one undo or redo. * curbuf->b_u_curhead points to the header of the last undo (the next redo), * or is NULL if nothing has been undone. * * All data is allocated with U_ALLOC_LINE(), it will be freed as soon as the * buffer is unloaded. */ #include "vim.h" /* See below: use malloc()/free() for memory management. */ #define U_USE_MALLOC 1 static u_entry_T *u_get_headentry __ARGS((void)); static void u_getbot __ARGS((void)); static int u_savecommon __ARGS((linenr_T, linenr_T, linenr_T)); static void u_doit __ARGS((int count)); static void u_undoredo __ARGS((void)); static void u_undo_end __ARGS((void)); static void u_freelist __ARGS((buf_T *buf, struct u_header *)); static void u_freeentry __ARGS((u_entry_T *, long)); #ifdef U_USE_MALLOC # define U_FREE_LINE(ptr) vim_free(ptr) # define U_ALLOC_LINE(size) lalloc((long_u)((size) + 1), FALSE) #else static void u_free_line __ARGS((char_u *ptr, int keep)); static char_u *u_alloc_line __ARGS((unsigned size)); # define U_FREE_LINE(ptr) u_free_line((ptr), FALSE) # define U_ALLOC_LINE(size) u_alloc_line(size) #endif static char_u *u_save_line __ARGS((linenr_T)); static long u_newcount, u_oldcount; /* * When 'u' flag included in 'cpoptions', we behave like vi. Need to remember * the action that "u" should do. */ static int undo_undoes = FALSE; /* * Save the current line for both the "u" and "U" command. * Returns OK or FAIL. */ int u_save_cursor() { return (u_save((linenr_T)(curwin->w_cursor.lnum - 1), (linenr_T)(curwin->w_cursor.lnum + 1))); } /* * Save the lines between "top" and "bot" for both the "u" and "U" command. * "top" may be 0 and bot may be curbuf->b_ml.ml_line_count + 1. * Returns FAIL when lines could not be saved, OK otherwise. */ int u_save(top, bot) linenr_T top, bot; { if (undo_off) return OK; if (top > curbuf->b_ml.ml_line_count || top >= bot || bot > curbuf->b_ml.ml_line_count + 1) return FALSE; /* rely on caller to do error messages */ if (top + 2 == bot) u_saveline((linenr_T)(top + 1)); return (u_savecommon(top, bot, (linenr_T)0)); } /* * save the line "lnum" (used by ":s" and "~" command) * The line is replaced, so the new bottom line is lnum + 1. */ int u_savesub(lnum) linenr_T lnum; { if (undo_off) return OK; return (u_savecommon(lnum - 1, lnum + 1, lnum + 1)); } /* * a new line is inserted before line "lnum" (used by :s command) * The line is inserted, so the new bottom line is lnum + 1. */ int u_inssub(lnum) linenr_T lnum; { if (undo_off) return OK; return (u_savecommon(lnum - 1, lnum, lnum + 1)); } /* * save the lines "lnum" - "lnum" + nlines (used by delete command) * The lines are deleted, so the new bottom line is lnum, unless the buffer * becomes empty. */ int u_savedel(lnum, nlines) linenr_T lnum; long nlines; { if (undo_off) return OK; return (u_savecommon(lnum - 1, lnum + nlines, nlines == curbuf->b_ml.ml_line_count ? 2 : lnum)); } static int u_savecommon(top, bot, newbot) linenr_T top, bot; linenr_T newbot; { linenr_T lnum; long i; struct u_header *uhp; u_entry_T *uep; u_entry_T *prev_uep; long size; /* * Don't allow changes when 'modifiable' is off. Letting the * undo fail is a crude way to make all change commands fail. */ if (!curbuf->b_p_ma) { EMSG(_(e_modifiable)); return FAIL; } #ifdef HAVE_SANDBOX /* * In the sandbox it's not allowed to change the text. Letting the * undo fail is a crude way to make all change commands fail. */ if (sandbox != 0) { EMSG(_(e_sandbox)); return FAIL; } #endif #ifdef FEAT_NETBEANS_INTG /* * Netbeans defines areas that cannot be modified. Bail out here when * trying to change text in a guarded area. */ if (usingNetbeans) { if (netbeans_is_guarded(top, bot)) { EMSG(_(e_guarded)); return FAIL; } if (curbuf->b_p_ro) { EMSG(_(e_nbreadonly)); return FAIL; } } #endif #ifdef FEAT_AUTOCMD /* * Saving text for undo means we are going to make a change. Give a * warning for a read-only file before making the change, so that the * FileChangedRO event can replace the buffer with a read-write version * (e.g., obtained from a source control system). */ change_warning(0); #endif size = bot - top - 1; /* * if curbuf->b_u_synced == TRUE make a new header */ if (curbuf->b_u_synced) { #ifdef FEAT_JUMPLIST /* Need to create new entry in b_changelist. */ curbuf->b_new_change = TRUE; #endif /* * if we undid more than we redid, free the entry lists before and * including curbuf->b_u_curhead */ while (curbuf->b_u_curhead != NULL) u_freelist(curbuf, curbuf->b_u_newhead); /* * free headers to keep the size right */ while (curbuf->b_u_numhead > p_ul && curbuf->b_u_oldhead != NULL) u_freelist(curbuf, curbuf->b_u_oldhead); if (p_ul < 0) /* no undo at all */ { curbuf->b_u_synced = FALSE; return OK; } /* * make a new header entry */ uhp = (struct u_header *)U_ALLOC_LINE((unsigned) sizeof(struct u_header)); if (uhp == NULL) goto nomem; uhp->uh_prev = NULL; uhp->uh_next = curbuf->b_u_newhead; if (curbuf->b_u_newhead != NULL) curbuf->b_u_newhead->uh_prev = uhp; uhp->uh_entry = NULL; uhp->uh_getbot_entry = NULL; uhp->uh_cursor = curwin->w_cursor; /* save cursor pos. for undo */ #ifdef FEAT_VIRTUALEDIT if (virtual_active() && curwin->w_cursor.coladd > 0) uhp->uh_cursor_vcol = getviscol(); else uhp->uh_cursor_vcol = -1; #endif /* save changed and buffer empty flag for undo */ uhp->uh_flags = (curbuf->b_changed ? UH_CHANGED : 0) + ((curbuf->b_ml.ml_flags & ML_EMPTY) ? UH_EMPTYBUF : 0); /* save named marks for undo */ mch_memmove(uhp->uh_namedm, curbuf->b_namedm, sizeof(pos_T) * NMARKS); curbuf->b_u_newhead = uhp; if (curbuf->b_u_oldhead == NULL) curbuf->b_u_oldhead = uhp; ++curbuf->b_u_numhead; } else { if (p_ul < 0) /* no undo at all */ return OK; /* * When saving a single line, and it has been saved just before, it * doesn't make sense saving it again. Saves a lot of memory when * making lots of changes inside the same line. * This is only possible if the previous change didn't increase or * decrease the number of lines. * Check the ten last changes. More doesn't make sense and takes too * long. */ if (size == 1) { uep = u_get_headentry(); prev_uep = NULL; for (i = 0; i < 10; ++i) { if (uep == NULL) break; /* If lines have been inserted/deleted we give up. * Also when the line was included in a multi-line save. */ if ((curbuf->b_u_newhead->uh_getbot_entry != uep ? (uep->ue_top + uep->ue_size + 1 != (uep->ue_bot == 0 ? curbuf->b_ml.ml_line_count + 1 : uep->ue_bot)) : uep->ue_lcount != curbuf->b_ml.ml_line_count) || (uep->ue_size > 1 && top >= uep->ue_top && top + 2 <= uep->ue_top + uep->ue_size + 1)) break; /* If it's the same line we can skip saving it again. */ if (uep->ue_size == 1 && uep->ue_top == top) { if (i > 0) { /* It's not the last entry: get ue_bot for the last * entry now. Following deleted/inserted lines go to * the re-used entry. */ u_getbot(); curbuf->b_u_synced = FALSE; /* Move the found entry to become the last entry. The * order of undo/redo doesn't matter for the entries * we move it over, since they don't change the line * count and don't include this line. It does matter * for the found entry if the line count is changed by * the executed command. */ prev_uep->ue_next = uep->ue_next; uep->ue_next = curbuf->b_u_newhead->uh_entry; curbuf->b_u_newhead->uh_entry = uep; } /* The executed command may change the line count. */ if (newbot != 0) uep->ue_bot = newbot; else if (bot > curbuf->b_ml.ml_line_count) uep->ue_bot = 0; else { uep->ue_lcount = curbuf->b_ml.ml_line_count; curbuf->b_u_newhead->uh_getbot_entry = uep; } return OK; } prev_uep = uep; uep = uep->ue_next; } } /* find line number for ue_bot for previous u_save() */ u_getbot(); } #if !defined(UNIX) && !defined(DJGPP) && !defined(WIN32) && !defined(__EMX__) /* * With Amiga and MSDOS 16 bit we can't handle big undo's, because * then u_alloc_line would have to allocate a block larger than 32K */ if (size >= 8000) goto nomem; #endif /* * add lines in front of entry list */ uep = (u_entry_T *)U_ALLOC_LINE((unsigned)sizeof(u_entry_T)); if (uep == NULL) goto nomem; uep->ue_size = size; uep->ue_top = top; if (newbot != 0) uep->ue_bot = newbot; /* * Use 0 for ue_bot if bot is below last line. * Otherwise we have to compute ue_bot later. */ else if (bot > curbuf->b_ml.ml_line_count) uep->ue_bot = 0; else { uep->ue_lcount = curbuf->b_ml.ml_line_count; curbuf->b_u_newhead->uh_getbot_entry = uep; } if (size > 0) { if ((uep->ue_array = (char_u **)U_ALLOC_LINE( (unsigned)(sizeof(char_u *) * size))) == NULL) { u_freeentry(uep, 0L); goto nomem; } for (i = 0, lnum = top + 1; i < size; ++i) { if ((uep->ue_array[i] = u_save_line(lnum++)) == NULL) { u_freeentry(uep, i); goto nomem; } } } else uep->ue_array = NULL; uep->ue_next = curbuf->b_u_newhead->uh_entry; curbuf->b_u_newhead->uh_entry = uep; curbuf->b_u_synced = FALSE; undo_undoes = FALSE; return OK; nomem: msg_silent = 0; /* must display the prompt */ if (ask_yesno((char_u *)_("No undo possible; continue anyway"), TRUE) == 'y') { undo_off = TRUE; /* will be reset when character typed */ return OK; } do_outofmem_msg((long_u)0); return FAIL; } /* * If 'cpoptions' contains 'u': Undo the previous undo or redo (vi compatible). * If 'cpoptions' does not contain 'u': Always undo. */ void u_undo(count) int count; { /* * If we get an undo command while executing a macro, we behave like the * original vi. If this happens twice in one macro the result will not * be compatible. */ if (curbuf->b_u_synced == FALSE) { u_sync(); count = 1; } if (vim_strchr(p_cpo, CPO_UNDO) == NULL) undo_undoes = TRUE; else undo_undoes = !undo_undoes; u_doit(count); } /* * If 'cpoptions' contains 'u': Repeat the previous undo or redo. * If 'cpoptions' does not contain 'u': Always redo. */ void u_redo(count) int count; { if (vim_strchr(p_cpo, CPO_UNDO) == NULL) undo_undoes = FALSE; u_doit(count); } /* * Undo or redo, depending on 'undo_undoes', 'count' times. */ static void u_doit(count) int count; { /* Don't allow changes when 'modifiable' is off. */ if (!curbuf->b_p_ma) { EMSG(_(e_modifiable)); return; } #ifdef HAVE_SANDBOX /* In the sandbox it's not allowed to change the text. */ if (sandbox != 0) { EMSG(_(e_sandbox)); return; } #endif u_newcount = 0; u_oldcount = 0; if (curbuf->b_ml.ml_flags & ML_EMPTY) u_oldcount = -1; while (count--) { if (undo_undoes) { if (curbuf->b_u_curhead == NULL) /* first undo */ curbuf->b_u_curhead = curbuf->b_u_newhead; else if (p_ul > 0) /* multi level undo */ /* get next undo */ curbuf->b_u_curhead = curbuf->b_u_curhead->uh_next; /* nothing to undo */ if (curbuf->b_u_numhead == 0 || curbuf->b_u_curhead == NULL) { /* stick curbuf->b_u_curhead at end */ curbuf->b_u_curhead = curbuf->b_u_oldhead; beep_flush(); break; } u_undoredo(); } else { if (curbuf->b_u_curhead == NULL || p_ul <= 0) { beep_flush(); /* nothing to redo */ break; } u_undoredo(); /* advance for next redo */ curbuf->b_u_curhead = curbuf->b_u_curhead->uh_prev; } } if (curbuf->b_ml.ml_flags & ML_EMPTY) --u_newcount; u_undo_end(); } /* * u_undoredo: common code for undo and redo * * The lines in the file are replaced by the lines in the entry list at * curbuf->b_u_curhead. The replaced lines in the file are saved in the entry * list for the next undo/redo. */ static void u_undoredo() { char_u **newarray = NULL; linenr_T oldsize; linenr_T newsize; linenr_T top, bot; linenr_T lnum; linenr_T newlnum = MAXLNUM; long i; u_entry_T *uep, *nuep; u_entry_T *newlist = NULL; int old_flags; int new_flags; pos_T namedm[NMARKS]; int empty_buffer; /* buffer became empty */ old_flags = curbuf->b_u_curhead->uh_flags; new_flags = (curbuf->b_changed ? UH_CHANGED : 0) + ((curbuf->b_ml.ml_flags & ML_EMPTY) ? UH_EMPTYBUF : 0); setpcmark(); /* * save marks before undo/redo */ mch_memmove(namedm, curbuf->b_namedm, sizeof(pos_T) * NMARKS); curbuf->b_op_start.lnum = curbuf->b_ml.ml_line_count; curbuf->b_op_start.col = 0; curbuf->b_op_end.lnum = 0; curbuf->b_op_end.col = 0; for (uep = curbuf->b_u_curhead->uh_entry; uep != NULL; uep = nuep) { top = uep->ue_top; bot = uep->ue_bot; if (bot == 0) bot = curbuf->b_ml.ml_line_count + 1; if (top > curbuf->b_ml.ml_line_count || top >= bot || bot > curbuf->b_ml.ml_line_count + 1) { EMSG(_("E438: u_undo: line numbers wrong")); changed(); /* don't want UNCHANGED now */ return; } oldsize = bot - top - 1; /* number of lines before undo */ newsize = uep->ue_size; /* number of lines after undo */ if (top < newlnum) { /* If the saved cursor is somewhere in this undo block, move it to * the remembered position. Makes "gwap" put the cursor back * where it was. */ lnum = curbuf->b_u_curhead->uh_cursor.lnum; if (lnum >= top && lnum <= top + newsize + 1) { curwin->w_cursor = curbuf->b_u_curhead->uh_cursor; newlnum = curwin->w_cursor.lnum - 1; } else { /* Use the first line that actually changed. Avoids that * undoing auto-formatting puts the cursor in the previous * line. */ for (i = 0; i < newsize && i < oldsize; ++i) if (STRCMP(uep->ue_array[i], ml_get(top + 1 + i)) != 0) break; if (i == newsize && newlnum == MAXLNUM && uep->ue_next == NULL) { newlnum = top; curwin->w_cursor.lnum = newlnum + 1; } else if (i < newsize) { newlnum = top + i; curwin->w_cursor.lnum = newlnum + 1; } } } empty_buffer = FALSE; /* delete the lines between top and bot and save them in newarray */ if (oldsize > 0) { if ((newarray = (char_u **)U_ALLOC_LINE( (unsigned)(sizeof(char_u *) * oldsize))) == NULL) { do_outofmem_msg((long_u)(sizeof(char_u *) * oldsize)); /* * We have messed up the entry list, repair is impossible. * we have to free the rest of the list. */ while (uep != NULL) { nuep = uep->ue_next; u_freeentry(uep, uep->ue_size); uep = nuep; } break; } /* delete backwards, it goes faster in most cases */ for (lnum = bot - 1, i = oldsize; --i >= 0; --lnum) { /* what can we do when we run out of memory? */ if ((newarray[i] = u_save_line(lnum)) == NULL) do_outofmem_msg((long_u)0); /* remember we deleted the last line in the buffer, and a * dummy empty line will be inserted */ if (curbuf->b_ml.ml_line_count == 1) empty_buffer = TRUE; ml_delete(lnum, FALSE); } } else newarray = NULL; /* insert the lines in u_array between top and bot */ if (newsize) { for (lnum = top, i = 0; i < newsize; ++i, ++lnum) { /* * If the file is empty, there is an empty line 1 that we * should get rid of, by replacing it with the new line */ if (empty_buffer && lnum == 0) ml_replace((linenr_T)1, uep->ue_array[i], TRUE); else ml_append(lnum, uep->ue_array[i], (colnr_T)0, FALSE); U_FREE_LINE(uep->ue_array[i]); } U_FREE_LINE((char_u *)uep->ue_array); } /* adjust marks */ if (oldsize != newsize) { mark_adjust(top + 1, top + oldsize, (long)MAXLNUM, (long)newsize - (long)oldsize); if (curbuf->b_op_start.lnum > top + oldsize) curbuf->b_op_start.lnum += newsize - oldsize; if (curbuf->b_op_end.lnum > top + oldsize) curbuf->b_op_end.lnum += newsize - oldsize; } changed_lines(top + 1, 0, bot, newsize - oldsize); /* set '[ and '] mark */ if (top + 1 < curbuf->b_op_start.lnum) curbuf->b_op_start.lnum = top + 1; if (newsize == 0 && top + 1 > curbuf->b_op_end.lnum) curbuf->b_op_end.lnum = top + 1; else if (top + newsize > curbuf->b_op_end.lnum) curbuf->b_op_end.lnum = top + newsize; u_newcount += newsize; u_oldcount += oldsize; uep->ue_size = oldsize; uep->ue_array = newarray; uep->ue_bot = top + newsize + 1; /* * insert this entry in front of the new entry list */ nuep = uep->ue_next; uep->ue_next = newlist; newlist = uep; } curbuf->b_u_curhead->uh_entry = newlist; curbuf->b_u_curhead->uh_flags = new_flags; if ((old_flags & UH_EMPTYBUF) && bufempty()) curbuf->b_ml.ml_flags |= ML_EMPTY; if (old_flags & UH_CHANGED) changed(); else #ifdef FEAT_NETBEANS_INTG /* per netbeans undo rules, keep it as modified */ if (!isNetbeansModified(curbuf)) #endif unchanged(curbuf, FALSE); /* * restore marks from before undo/redo */ for (i = 0; i < NMARKS; ++i) if (curbuf->b_u_curhead->uh_namedm[i].lnum) { curbuf->b_namedm[i] = curbuf->b_u_curhead->uh_namedm[i]; curbuf->b_u_curhead->uh_namedm[i] = namedm[i]; } /* * If the cursor is only off by one line, put it at the same position as * before starting the change (for the "o" command). * Otherwise the cursor should go to the first undone line. */ if (curbuf->b_u_curhead->uh_cursor.lnum + 1 == curwin->w_cursor.lnum && curwin->w_cursor.lnum > 1) --curwin->w_cursor.lnum; if (curbuf->b_u_curhead->uh_cursor.lnum == curwin->w_cursor.lnum) { curwin->w_cursor.col = curbuf->b_u_curhead->uh_cursor.col; #ifdef FEAT_VIRTUALEDIT if (virtual_active() && curbuf->b_u_curhead->uh_cursor_vcol >= 0) coladvance((colnr_T)curbuf->b_u_curhead->uh_cursor_vcol); else curwin->w_cursor.coladd = 0; #endif } else if (curwin->w_cursor.lnum <= curbuf->b_ml.ml_line_count) beginline(BL_SOL | BL_FIX); else { /* We get here with the current cursor line being past the end (eg * after adding lines at the end of the file, and then undoing it). * check_cursor() will move the cursor to the last line. Move it to * the first column here. */ curwin->w_cursor.col = 0; #ifdef FEAT_VIRTUALEDIT curwin->w_cursor.coladd = 0; #endif } /* Make sure the cursor is on an existing line and column. */ check_cursor(); } /* * If we deleted or added lines, report the number of less/more lines. * Otherwise, report the number of changes (this may be incorrect * in some cases, but it's better than nothing). */ static void u_undo_end() { if ((u_oldcount -= u_newcount) != 0) msgmore(-u_oldcount); else if (u_newcount > p_report) { if (u_newcount == 1) MSG(_("1 change")); else smsg((char_u *)_("%ld changes"), u_newcount); } #ifdef FEAT_FOLDING if ((fdo_flags & FDO_UNDO) && KeyTyped) foldOpenCursor(); #endif } /* * u_sync: stop adding to the current entry list */ void u_sync() { if (curbuf->b_u_synced) return; /* already synced */ #if defined(FEAT_XIM) && defined(FEAT_GUI_GTK) if (im_is_preediting()) return; /* XIM is busy, don't break an undo sequence */ #endif if (p_ul < 0) curbuf->b_u_synced = TRUE; /* no entries, nothing to do */ else { u_getbot(); /* compute ue_bot of previous u_save */ curbuf->b_u_curhead = NULL; } } /* * Called after writing the file and setting b_changed to FALSE. * Now an undo means that the buffer is modified. */ void u_unchanged(buf) buf_T *buf; { struct u_header *uh; for (uh = buf->b_u_newhead; uh; uh = uh->uh_next) uh->uh_flags |= UH_CHANGED; buf->b_did_warn = FALSE; } /* * Get pointer to last added entry. * If it's not valid, give an error message and return NULL. */ static u_entry_T * u_get_headentry() { if (curbuf->b_u_newhead == NULL || curbuf->b_u_newhead->uh_entry == NULL) { EMSG(_("E439: undo list corrupt")); return NULL; } return curbuf->b_u_newhead->uh_entry; } /* * u_getbot(): compute the line number of the previous u_save * It is called only when b_u_synced is FALSE. */ static void u_getbot() { u_entry_T *uep; linenr_T extra; uep = u_get_headentry(); /* check for corrupt undo list */ if (uep == NULL) return; uep = curbuf->b_u_newhead->uh_getbot_entry; if (uep != NULL) { /* * the new ue_bot is computed from the number of lines that has been * inserted (0 - deleted) since calling u_save. This is equal to the * old line count subtracted from the current line count. */ extra = curbuf->b_ml.ml_line_count - uep->ue_lcount; uep->ue_bot = uep->ue_top + uep->ue_size + 1 + extra; if (uep->ue_bot < 1 || uep->ue_bot > curbuf->b_ml.ml_line_count) { EMSG(_("E440: undo line missing")); uep->ue_bot = uep->ue_top + 1; /* assume all lines deleted, will * get all the old lines back * without deleting the current * ones */ } curbuf->b_u_newhead->uh_getbot_entry = NULL; } curbuf->b_u_synced = TRUE; } /* * u_freelist: free one entry list and adjust the pointers */ static void u_freelist(buf, uhp) buf_T *buf; struct u_header *uhp; { u_entry_T *uep, *nuep; for (uep = uhp->uh_entry; uep != NULL; uep = nuep) { nuep = uep->ue_next; u_freeentry(uep, uep->ue_size); } if (buf->b_u_curhead == uhp) buf->b_u_curhead = NULL; if (uhp->uh_next == NULL) buf->b_u_oldhead = uhp->uh_prev; else uhp->uh_next->uh_prev = uhp->uh_prev; if (uhp->uh_prev == NULL) buf->b_u_newhead = uhp->uh_next; else uhp->uh_prev->uh_next = uhp->uh_next; U_FREE_LINE((char_u *)uhp); --buf->b_u_numhead; } /* * free entry 'uep' and 'n' lines in uep->ue_array[] */ static void u_freeentry(uep, n) u_entry_T *uep; long n; { while (n > 0) U_FREE_LINE(uep->ue_array[--n]); U_FREE_LINE((char_u *)uep->ue_array); U_FREE_LINE((char_u *)uep); } /* * invalidate the undo buffer; called when storage has already been released */ void u_clearall(buf) buf_T *buf; { buf->b_u_newhead = buf->b_u_oldhead = buf->b_u_curhead = NULL; buf->b_u_synced = TRUE; buf->b_u_numhead = 0; buf->b_u_line_ptr = NULL; buf->b_u_line_lnum = 0; } /* * save the line "lnum" for the "U" command */ void u_saveline(lnum) linenr_T lnum; { if (lnum == curbuf->b_u_line_lnum) /* line is already saved */ return; if (lnum < 1 || lnum > curbuf->b_ml.ml_line_count) /* should never happen */ return; u_clearline(); curbuf->b_u_line_lnum = lnum; if (curwin->w_cursor.lnum == lnum) curbuf->b_u_line_colnr = curwin->w_cursor.col; else curbuf->b_u_line_colnr = 0; if ((curbuf->b_u_line_ptr = u_save_line(lnum)) == NULL) do_outofmem_msg((long_u)0); } /* * clear the line saved for the "U" command * (this is used externally for crossing a line while in insert mode) */ void u_clearline() { if (curbuf->b_u_line_ptr != NULL) { U_FREE_LINE(curbuf->b_u_line_ptr); curbuf->b_u_line_ptr = NULL; curbuf->b_u_line_lnum = 0; } } /* * Implementation of the "U" command. * Differentiation from vi: "U" can be undone with the next "U". * We also allow the cursor to be in another line. */ void u_undoline() { colnr_T t; char_u *oldp; if (undo_off) return; if (curbuf->b_u_line_ptr == NULL || curbuf->b_u_line_lnum > curbuf->b_ml.ml_line_count) { beep_flush(); return; } /* first save the line for the 'u' command */ if (u_savecommon(curbuf->b_u_line_lnum - 1, curbuf->b_u_line_lnum + 1, (linenr_T)0) == FAIL) return; oldp = u_save_line(curbuf->b_u_line_lnum); if (oldp == NULL) { do_outofmem_msg((long_u)0); return; } ml_replace(curbuf->b_u_line_lnum, curbuf->b_u_line_ptr, TRUE); changed_bytes(curbuf->b_u_line_lnum, 0); U_FREE_LINE(curbuf->b_u_line_ptr); curbuf->b_u_line_ptr = oldp; t = curbuf->b_u_line_colnr; if (curwin->w_cursor.lnum == curbuf->b_u_line_lnum) curbuf->b_u_line_colnr = curwin->w_cursor.col; curwin->w_cursor.col = t; curwin->w_cursor.lnum = curbuf->b_u_line_lnum; } /* * There are two implementations of the memory management for undo: * 1. Use the standard malloc()/free() functions. * This should be fast for allocating memory, but when a buffer is * abandoned every single allocated chunk must be freed, which may be slow. * 2. Allocate larger blocks of memory and keep track of chunks ourselves. * This is fast for abandoning, but the use of linked lists is slow for * finding a free chunk. Esp. when a lot of lines are changed or deleted. * A bit of profiling showed that the first method is faster, especially when * making a large number of changes, under the condition that malloc()/free() * is implemented efficiently. */ #ifdef U_USE_MALLOC /* * Version of undo memory allocation using malloc()/free() * * U_FREE_LINE() and U_ALLOC_LINE() are macros that invoke vim_free() and * lalloc() directly. */ /* * Free all allocated memory blocks for the buffer 'buf'. */ void u_blockfree(buf) buf_T *buf; { while (buf->b_u_newhead != NULL) u_freelist(buf, buf->b_u_newhead); U_FREE_LINE(buf->b_u_line_ptr); } #else /* * Storage allocation for the undo lines and blocks of the current file. * Version where Vim keeps track of the available memory. */ /* * Memory is allocated in relatively large blocks. These blocks are linked * in the allocated block list, headed by curbuf->b_block_head. They are all * freed when abandoning a file, so we don't have to free every single line. * The list is kept sorted on memory address. * block_alloc() allocates a block. * m_blockfree() frees all blocks. * * The available chunks of memory are kept in free chunk lists. There is * one free list for each block of allocated memory. The list is kept sorted * on memory address. * u_alloc_line() gets a chunk from the free lists. * u_free_line() returns a chunk to the free lists. * curbuf->b_m_search points to the chunk before the chunk that was * freed/allocated the last time. * curbuf->b_mb_current points to the b_head where curbuf->b_m_search * points into the free list. * * * b_block_head /---> block #1 /---> block #2 * mb_next ---/ mb_next ---/ mb_next ---> NULL * mb_info mb_info mb_info * | | | * V V V * NULL free chunk #1.1 free chunk #2.1 * | | * V V * free chunk #1.2 NULL * | * V * NULL * * When a single free chunk list would have been used, it could take a lot * of time in u_free_line() to find the correct place to insert a chunk in the * free list. The single free list would become very long when many lines are * changed (e.g. with :%s/^M$//). */ /* * this blocksize is used when allocating new lines */ #define MEMBLOCKSIZE 2044 /* * The size field contains the size of the chunk, including the size field * itself. * * When the chunk is not in-use it is preceded with the m_info structure. * The m_next field links it in one of the free chunk lists. * * On most unix systems structures have to be longword (32 or 64 bit) aligned. * On most other systems they are short (16 bit) aligned. */ /* the structure definitions are now in structs.h */ #ifdef ALIGN_LONG /* size of m_size */ # define M_OFFSET (sizeof(long_u)) #else /* size of m_size */ # define M_OFFSET (sizeof(short_u)) #endif static char_u *u_blockalloc __ARGS((long_u)); /* * Allocate a block of memory and link it in the allocated block list. */ static char_u * u_blockalloc(size) long_u size; { mblock_T *p; mblock_T *mp, *next; p = (mblock_T *)lalloc(size + sizeof(mblock_T), FALSE); if (p != NULL) { /* Insert the block into the allocated block list, keeping it sorted on address. */ for (mp = &curbuf->b_block_head; (next = mp->mb_next) != NULL && next < p; mp = next) ; p->mb_next = next; /* link in block list */ p->mb_size = size; p->mb_maxsize = 0; /* nothing free yet */ mp->mb_next = p; p->mb_info.m_next = NULL; /* clear free list */ p->mb_info.m_size = 0; curbuf->b_mb_current = p; /* remember current block */ curbuf->b_m_search = NULL; p++; /* return usable memory */ } return (char_u *)p; } /* * free all allocated memory blocks for the buffer 'buf' */ void u_blockfree(buf) buf_T *buf; { mblock_T *p, *np; for (p = buf->b_block_head.mb_next; p != NULL; p = np) { np = p->mb_next; vim_free(p); } buf->b_block_head.mb_next = NULL; buf->b_m_search = NULL; buf->b_mb_current = NULL; } /* * Free a chunk of memory for the current buffer. * Insert the chunk into the correct free list, keeping it sorted on address. */ static void u_free_line(ptr, keep) char_u *ptr; int keep; /* don't free the block when it's empty */ { minfo_T *next; minfo_T *prev, *curr; minfo_T *mp; mblock_T *nextb; mblock_T *prevb; long_u maxsize; if (ptr == NULL || ptr == IObuff) return; /* illegal address can happen in out-of-memory situations */ mp = (minfo_T *)(ptr - M_OFFSET); /* find block where chunk could be a part off */ /* if we change curbuf->b_mb_current, curbuf->b_m_search is set to NULL */ if (curbuf->b_mb_current == NULL || mp < (minfo_T *)curbuf->b_mb_current) { curbuf->b_mb_current = curbuf->b_block_head.mb_next; curbuf->b_m_search = NULL; } if ((nextb = curbuf->b_mb_current->mb_next) != NULL && (minfo_T *)nextb < mp) { curbuf->b_mb_current = nextb; curbuf->b_m_search = NULL; } while ((nextb = curbuf->b_mb_current->mb_next) != NULL && (minfo_T *)nextb < mp) curbuf->b_mb_current = nextb; curr = NULL; /* * If mp is smaller than curbuf->b_m_search->m_next go to the start of * the free list */ if (curbuf->b_m_search == NULL || mp < (curbuf->b_m_search->m_next)) next = &(curbuf->b_mb_current->mb_info); else next = curbuf->b_m_search; /* * The following loop is executed very often. * Therefore it has been optimized at the cost of readability. * Keep it fast! */ #ifdef SLOW_BUT_EASY_TO_READ do { prev = curr; curr = next; next = next->m_next; } while (mp > next && next != NULL); #else do /* first, middle, last */ { prev = next->m_next; /* curr, next, prev */ if (prev == NULL || mp <= prev) { prev = curr; curr = next; next = next->m_next; break; } curr = prev->m_next; /* next, prev, curr */ if (curr == NULL || mp <= curr) { prev = next; curr = prev->m_next; next = curr->m_next; break; } next = curr->m_next; /* prev, curr, next */ } while (mp > next && next != NULL); #endif /* if *mp and *next are concatenated, join them into one chunk */ if ((char_u *)mp + mp->m_size == (char_u *)next) { mp->m_size += next->m_size; mp->m_next = next->m_next; } else mp->m_next = next; maxsize = mp->m_size; /* if *curr and *mp are concatenated, join them */ if (prev != NULL && (char_u *)curr + curr->m_size == (char_u *)mp) { curr->m_size += mp->m_size; maxsize = curr->m_size; curr->m_next = mp->m_next; curbuf->b_m_search = prev; } else { curr->m_next = mp; curbuf->b_m_search = curr; /* put curbuf->b_m_search before freed chunk */ } /* * If the block only containes free memory now, release it. */ if (!keep && curbuf->b_mb_current->mb_size == curbuf->b_mb_current->mb_info.m_next->m_size) { /* Find the block before the current one to be able to unlink it from * the list of blocks. */ prevb = &curbuf->b_block_head; for (nextb = prevb->mb_next; nextb != curbuf->b_mb_current; nextb = nextb->mb_next) prevb = nextb; prevb->mb_next = nextb->mb_next; vim_free(nextb); curbuf->b_mb_current = NULL; curbuf->b_m_search = NULL; } else if (curbuf->b_mb_current->mb_maxsize < maxsize) curbuf->b_mb_current->mb_maxsize = maxsize; } /* * Allocate and initialize a new line structure with room for at least * 'size' characters plus a terminating NUL. */ static char_u * u_alloc_line(size) unsigned size; { minfo_T *mp, *mprev, *mp2; mblock_T *mbp; int size_align; /* * Add room for size field and trailing NUL byte. * Adjust for minimal size (must be able to store minfo_T * plus a trailing NUL, so the chunk can be released again) */ size += M_OFFSET + 1; if (size < sizeof(minfo_T) + 1) size = sizeof(minfo_T) + 1; /* * round size up for alignment */ size_align = (size + ALIGN_MASK) & ~ALIGN_MASK; /* * If curbuf->b_m_search is NULL (uninitialized free list) start at * curbuf->b_block_head */ if (curbuf->b_mb_current == NULL || curbuf->b_m_search == NULL) { curbuf->b_mb_current = &curbuf->b_block_head; curbuf->b_m_search = &(curbuf->b_block_head.mb_info); } /* Search for a block with enough space. */ mbp = curbuf->b_mb_current; while (mbp->mb_maxsize < size_align) { if (mbp->mb_next != NULL) mbp = mbp->mb_next; else mbp = &curbuf->b_block_head; if (mbp == curbuf->b_mb_current) { int n = (size_align > (MEMBLOCKSIZE / 4) ? size_align : MEMBLOCKSIZE); /* Back where we started in block list: need to add a new block * with enough space. */ mp = (minfo_T *)u_blockalloc((long_u)n); if (mp == NULL) return (NULL); mp->m_size = n; u_free_line((char_u *)mp + M_OFFSET, TRUE); mbp = curbuf->b_mb_current; break; } } if (mbp != curbuf->b_mb_current) curbuf->b_m_search = &(mbp->mb_info); /* In this block find a chunk with enough space. */ mprev = curbuf->b_m_search; mp = curbuf->b_m_search->m_next; for (;;) { if (mp == NULL) /* at end of the list */ mp = &(mbp->mb_info); /* wrap around to begin */ if (mp->m_size >= size) break; if (mp == curbuf->b_m_search) { /* back where we started in free chunk list: "cannot happen" */ EMSG2(_(e_intern2), "u_alloc_line()"); return NULL; } mprev = mp; mp = mp->m_next; } /* when using the largest chunk adjust mb_maxsize */ if (mp->m_size >= mbp->mb_maxsize) mbp->mb_maxsize = 0; /* if the chunk we found is large enough, split it up in two */ if ((long)mp->m_size - size_align >= (long)(sizeof(minfo_T) + 1)) { mp2 = (minfo_T *)((char_u *)mp + size_align); mp2->m_size = mp->m_size - size_align; mp2->m_next = mp->m_next; mprev->m_next = mp2; mp->m_size = size_align; } else /* remove *mp from the free list */ { mprev->m_next = mp->m_next; } curbuf->b_m_search = mprev; curbuf->b_mb_current = mbp; /* If using the largest chunk need to find the new largest chunk */ if (mbp->mb_maxsize == 0) for (mp2 = &(mbp->mb_info); mp2 != NULL; mp2 = mp2->m_next) if (mbp->mb_maxsize < mp2->m_size) mbp->mb_maxsize = mp2->m_size; mp = (minfo_T *)((char_u *)mp + M_OFFSET); *(char_u *)mp = NUL; /* set the first byte to NUL */ return ((char_u *)mp); } #endif /* * u_save_line(): allocate memory with u_alloc_line() and copy line 'lnum' * into it. */ static char_u * u_save_line(lnum) linenr_T lnum; { char_u *src; char_u *dst; unsigned len; src = ml_get(lnum); len = (unsigned)STRLEN(src); if ((dst = U_ALLOC_LINE(len)) != NULL) mch_memmove(dst, src, (size_t)(len + 1)); return (dst); } /* * Check if the 'modified' flag is set, or 'ff' has changed (only need to * check the first character, because it can only be "dos", "unix" or "mac"). * "nofile" and "scratch" type buffers are considered to always be unchanged. */ int bufIsChanged(buf) buf_T *buf; { return #ifdef FEAT_QUICKFIX !bt_dontwrite(buf) && #endif (buf->b_changed || file_ff_differs(buf)); } int curbufIsChanged() { return #ifdef FEAT_QUICKFIX !bt_dontwrite(curbuf) && #endif (curbuf->b_changed || file_ff_differs(curbuf)); }