diff options
Diffstat (limited to 'src/nvim/undo.c')
| -rw-r--r-- | src/nvim/undo.c | 2880 |
1 files changed, 2880 insertions, 0 deletions
diff --git a/src/nvim/undo.c b/src/nvim/undo.c new file mode 100644 index 0000000000..47ce8ee8da --- /dev/null +++ b/src/nvim/undo.c @@ -0,0 +1,2880 @@ +/* + * 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 (end of the branch). + * + * For keeping alternate undo/redo branches the uh_alt field is used. Thus at + * each point in the list a branch may appear for an alternate to redo. The + * uh_seq field is numbered sequentially to be able to find a newer or older + * branch. + * + * +---------------+ +---------------+ + * b_u_oldhead --->| u_header | | u_header | + * | uh_alt_next ---->| uh_alt_next ----> NULL + * NULL <----- uh_alt_prev |<------ uh_alt_prev | + * | uh_prev | | uh_prev | + * +-----|---------+ +-----|---------+ + * | | + * V V + * +---------------+ +---------------+ + * | u_header | | u_header | + * | uh_alt_next | | uh_alt_next | + * b_u_newhead --->| uh_alt_prev | | uh_alt_prev | + * | uh_prev | | uh_prev | + * +-----|---------+ +-----|---------+ + * | | + * V V + * NULL +---------------+ +---------------+ + * | u_header | | u_header | + * | uh_alt_next ---->| uh_alt_next | + * | uh_alt_prev |<------ uh_alt_prev | + * | uh_prev | | uh_prev | + * +-----|---------+ +-----|---------+ + * | | + * etc. etc. + * + * + * All data is allocated and will all be freed when the buffer is unloaded. + */ + +/* Uncomment the next line for including the u_check() function. This warns + * for errors in the debug information. */ +/* #define U_DEBUG 1 */ +#define UH_MAGIC 0x18dade /* value for uh_magic when in use */ +#define UE_MAGIC 0xabc123 /* value for ue_magic when in use */ + +#include <string.h> + +#include "vim.h" +#include "undo.h" +#include "edit.h" +#include "eval.h" +#include "fileio.h" +#include "fold.h" +#include "mark.h" +#include "memline.h" +#include "message.h" +#include "misc1.h" +#include "misc2.h" +#include "memory.h" +#include "crypt.h" +#include "garray.h" +#include "option.h" +#include "os_unix.h" +#include "path.h" +#include "quickfix.h" +#include "screen.h" +#include "sha256.h" +#include "os/os.h" +#include "os/time.h" + +static long get_undolevel(void); +static void u_unch_branch(u_header_T *uhp); +static u_entry_T *u_get_headentry(void); +static void u_getbot(void); +static void u_doit(int count); +static void u_undoredo(int undo); +static void u_undo_end(int did_undo, int absolute); +static void u_add_time(char_u *buf, size_t buflen, time_t tt); +static void u_freeheader(buf_T *buf, u_header_T *uhp, u_header_T **uhpp); +static void u_freebranch(buf_T *buf, u_header_T *uhp, u_header_T **uhpp); +static void u_freeentries(buf_T *buf, u_header_T *uhp, + u_header_T **uhpp); +static void u_freeentry(u_entry_T *, long); +static void corruption_error(char *mesg, char_u *file_name); +static void u_free_uhp(u_header_T *uhp); +static size_t fwrite_crypt(buf_T *buf, char_u *ptr, size_t len, + FILE *fp); +static char_u *read_string_decrypt(buf_T *buf, FILE *fd, int len); +static int serialize_header(FILE *fp, buf_T *buf, char_u *hash); +static int serialize_uhp(FILE *fp, buf_T *buf, u_header_T *uhp); +static u_header_T *unserialize_uhp(FILE *fp, char_u *file_name); +static int serialize_uep(FILE *fp, buf_T *buf, u_entry_T *uep); +static u_entry_T *unserialize_uep(FILE *fp, int *error, + char_u *file_name); +static void serialize_pos(pos_T pos, FILE *fp); +static void unserialize_pos(pos_T *pos, FILE *fp); +static void serialize_visualinfo(visualinfo_T *info, FILE *fp); +static void unserialize_visualinfo(visualinfo_T *info, FILE *fp); +static void put_header_ptr(FILE *fp, u_header_T *uhp); + +static char_u *u_save_line(linenr_T); + +/* used in undo_end() to report number of added and deleted lines */ +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; + +static int lastmark = 0; + +#if defined(U_DEBUG) || defined(PROTO) +/* + * Check the undo structures for being valid. Print a warning when something + * looks wrong. + */ +static int seen_b_u_curhead; +static int seen_b_u_newhead; +static int header_count; + +static void u_check_tree(u_header_T *uhp, + u_header_T *exp_uh_next, + u_header_T *exp_uh_alt_prev) { + u_entry_T *uep; + + if (uhp == NULL) + return; + ++header_count; + if (uhp == curbuf->b_u_curhead && ++seen_b_u_curhead > 1) { + EMSG("b_u_curhead found twice (looping?)"); + return; + } + if (uhp == curbuf->b_u_newhead && ++seen_b_u_newhead > 1) { + EMSG("b_u_newhead found twice (looping?)"); + return; + } + + if (uhp->uh_magic != UH_MAGIC) + EMSG("uh_magic wrong (may be using freed memory)"); + else { + /* Check pointers back are correct. */ + if (uhp->uh_next.ptr != exp_uh_next) { + EMSG("uh_next wrong"); + smsg((char_u *)"expected: 0x%x, actual: 0x%x", + exp_uh_next, uhp->uh_next.ptr); + } + if (uhp->uh_alt_prev.ptr != exp_uh_alt_prev) { + EMSG("uh_alt_prev wrong"); + smsg((char_u *)"expected: 0x%x, actual: 0x%x", + exp_uh_alt_prev, uhp->uh_alt_prev.ptr); + } + + /* Check the undo tree at this header. */ + for (uep = uhp->uh_entry; uep != NULL; uep = uep->ue_next) { + if (uep->ue_magic != UE_MAGIC) { + EMSG("ue_magic wrong (may be using freed memory)"); + break; + } + } + + /* Check the next alt tree. */ + u_check_tree(uhp->uh_alt_next.ptr, uhp->uh_next.ptr, uhp); + + /* Check the next header in this branch. */ + u_check_tree(uhp->uh_prev.ptr, uhp, NULL); + } +} + +static void u_check(int newhead_may_be_NULL) { + seen_b_u_newhead = 0; + seen_b_u_curhead = 0; + header_count = 0; + + u_check_tree(curbuf->b_u_oldhead, NULL, NULL); + + if (seen_b_u_newhead == 0 && curbuf->b_u_oldhead != NULL + && !(newhead_may_be_NULL && curbuf->b_u_newhead == NULL)) + EMSGN("b_u_newhead invalid: 0x%x", curbuf->b_u_newhead); + if (curbuf->b_u_curhead != NULL && seen_b_u_curhead == 0) + EMSGN("b_u_curhead invalid: 0x%x", curbuf->b_u_curhead); + if (header_count != curbuf->b_u_numhead) { + EMSG("b_u_numhead invalid"); + smsg((char_u *)"expected: %" PRId64 ", actual: %" PRId64, + (int64_t)header_count, (int64_t)curbuf->b_u_numhead); + } +} + +#endif + +/* + * Save the current line for both the "u" and "U" command. + * Careful: may trigger autocommands that reload the buffer. + * Returns OK or FAIL. + */ +int u_save_cursor(void) +{ + 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. + * Careful: may trigger autocommands that reload the buffer. + * Returns FAIL when lines could not be saved, OK otherwise. + */ +int u_save(linenr_T top, linenr_T 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, FALSE); +} + +/* + * Save the line "lnum" (used by ":s" and "~" command). + * The line is replaced, so the new bottom line is lnum + 1. + * Careful: may trigger autocommands that reload the buffer. + * Returns FAIL when lines could not be saved, OK otherwise. + */ +int u_savesub(linenr_T lnum) +{ + if (undo_off) + return OK; + + return u_savecommon(lnum - 1, lnum + 1, lnum + 1, FALSE); +} + +/* + * A new line is inserted before line "lnum" (used by :s command). + * The line is inserted, so the new bottom line is lnum + 1. + * Careful: may trigger autocommands that reload the buffer. + * Returns FAIL when lines could not be saved, OK otherwise. + */ +int u_inssub(linenr_T lnum) +{ + if (undo_off) + return OK; + + return u_savecommon(lnum - 1, lnum, lnum + 1, FALSE); +} + +/* + * 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. + * Careful: may trigger autocommands that reload the buffer. + * Returns FAIL when lines could not be saved, OK otherwise. + */ +int u_savedel(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, FALSE); +} + +/* + * Return TRUE when undo is allowed. Otherwise give an error message and + * return FALSE. + */ +int undo_allowed(void) +{ + /* Don't allow changes when 'modifiable' is off. */ + if (!curbuf->b_p_ma) { + EMSG(_(e_modifiable)); + return FALSE; + } + +#ifdef HAVE_SANDBOX + /* In the sandbox it's not allowed to change the text. */ + if (sandbox != 0) { + EMSG(_(e_sandbox)); + return FALSE; + } +#endif + + /* Don't allow changes in the buffer while editing the cmdline. The + * caller of getcmdline() may get confused. */ + if (textlock != 0) { + EMSG(_(e_secure)); + return FALSE; + } + + return TRUE; +} + +/* + * Get the undolevle value for the current buffer. + */ +static long get_undolevel(void) +{ + if (curbuf->b_p_ul == NO_LOCAL_UNDOLEVEL) + return p_ul; + return curbuf->b_p_ul; +} + +/* + * Common code for various ways to save text before a change. + * "top" is the line above the first changed line. + * "bot" is the line below the last changed line. + * "newbot" is the new bottom line. Use zero when not known. + * "reload" is TRUE when saving for a buffer reload. + * Careful: may trigger autocommands that reload the buffer. + * Returns FAIL when lines could not be saved, OK otherwise. + */ +int u_savecommon(linenr_T top, linenr_T bot, linenr_T newbot, int reload) +{ + linenr_T lnum; + long i; + u_header_T *uhp; + u_header_T *old_curhead; + u_entry_T *uep; + u_entry_T *prev_uep; + long size; + + if (!reload) { + /* When making changes is not allowed return FAIL. It's a crude way + * to make all change commands fail. */ + if (!undo_allowed()) + return FAIL; + + + /* + * 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); + if (bot > curbuf->b_ml.ml_line_count + 1) { + /* This happens when the FileChangedRO autocommand changes the + * file in a way it becomes shorter. */ + EMSG(_("E881: Line count changed unexpectedly")); + return FAIL; + } + } + +#ifdef U_DEBUG + u_check(FALSE); +#endif + + size = bot - top - 1; + + /* + * If curbuf->b_u_synced == TRUE make a new header. + */ + if (curbuf->b_u_synced) { + /* Need to create new entry in b_changelist. */ + curbuf->b_new_change = TRUE; + + if (get_undolevel() >= 0) { + /* + * Make a new header entry. Do this first so that we don't mess + * up the undo info when out of memory. + */ + uhp = xmalloc(sizeof(u_header_T)); +#ifdef U_DEBUG + uhp->uh_magic = UH_MAGIC; +#endif + } else + uhp = NULL; + + /* + * If we undid more than we redid, move the entry lists before and + * including curbuf->b_u_curhead to an alternate branch. + */ + old_curhead = curbuf->b_u_curhead; + if (old_curhead != NULL) { + curbuf->b_u_newhead = old_curhead->uh_next.ptr; + curbuf->b_u_curhead = NULL; + } + + /* + * free headers to keep the size right + */ + while (curbuf->b_u_numhead > get_undolevel() + && curbuf->b_u_oldhead != NULL) { + u_header_T *uhfree = curbuf->b_u_oldhead; + + if (uhfree == old_curhead) + /* Can't reconnect the branch, delete all of it. */ + u_freebranch(curbuf, uhfree, &old_curhead); + else if (uhfree->uh_alt_next.ptr == NULL) + /* There is no branch, only free one header. */ + u_freeheader(curbuf, uhfree, &old_curhead); + else { + /* Free the oldest alternate branch as a whole. */ + while (uhfree->uh_alt_next.ptr != NULL) + uhfree = uhfree->uh_alt_next.ptr; + u_freebranch(curbuf, uhfree, &old_curhead); + } +#ifdef U_DEBUG + u_check(TRUE); +#endif + } + + if (uhp == NULL) { /* no undo at all */ + if (old_curhead != NULL) + u_freebranch(curbuf, old_curhead, NULL); + curbuf->b_u_synced = FALSE; + return OK; + } + + uhp->uh_prev.ptr = NULL; + uhp->uh_next.ptr = curbuf->b_u_newhead; + uhp->uh_alt_next.ptr = old_curhead; + if (old_curhead != NULL) { + uhp->uh_alt_prev.ptr = old_curhead->uh_alt_prev.ptr; + if (uhp->uh_alt_prev.ptr != NULL) + uhp->uh_alt_prev.ptr->uh_alt_next.ptr = uhp; + old_curhead->uh_alt_prev.ptr = uhp; + if (curbuf->b_u_oldhead == old_curhead) + curbuf->b_u_oldhead = uhp; + } else + uhp->uh_alt_prev.ptr = NULL; + if (curbuf->b_u_newhead != NULL) + curbuf->b_u_newhead->uh_prev.ptr = uhp; + + uhp->uh_seq = ++curbuf->b_u_seq_last; + curbuf->b_u_seq_cur = uhp->uh_seq; + uhp->uh_time = time(NULL); + uhp->uh_save_nr = 0; + curbuf->b_u_time_cur = uhp->uh_time + 1; + + uhp->uh_walk = 0; + uhp->uh_entry = NULL; + uhp->uh_getbot_entry = NULL; + uhp->uh_cursor = curwin->w_cursor; /* save cursor pos. for undo */ + if (virtual_active() && curwin->w_cursor.coladd > 0) + uhp->uh_cursor_vcol = getviscol(); + else + uhp->uh_cursor_vcol = -1; + + /* 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 and Visual marks for undo */ + memmove(uhp->uh_namedm, curbuf->b_namedm, sizeof(pos_T) * NMARKS); + uhp->uh_visual = curbuf->b_visual; + + curbuf->b_u_newhead = uhp; + if (curbuf->b_u_oldhead == NULL) + curbuf->b_u_oldhead = uhp; + ++curbuf->b_u_numhead; + } else { + if (get_undolevel() < 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(); + } + + /* + * add lines in front of entry list + */ + uep = xmalloc(sizeof(u_entry_T)); + memset(uep, 0, sizeof(u_entry_T)); +#ifdef U_DEBUG + uep->ue_magic = UE_MAGIC; +#endif + + 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) { + uep->ue_array = xmalloc(sizeof(char_u *) * size); + for (i = 0, lnum = top + 1; i < size; ++i) { + fast_breakcheck(); + if (got_int) { + u_freeentry(uep, i); + return FAIL; + } + 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; + +#ifdef U_DEBUG + u_check(FALSE); +#endif + 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; +} + + +# define UF_START_MAGIC "Vim\237UnDo\345" /* magic at start of undofile */ +# define UF_START_MAGIC_LEN 9 +# define UF_HEADER_MAGIC 0x5fd0 /* magic at start of header */ +# define UF_HEADER_END_MAGIC 0xe7aa /* magic after last header */ +# define UF_ENTRY_MAGIC 0xf518 /* magic at start of entry */ +# define UF_ENTRY_END_MAGIC 0x3581 /* magic after last entry */ +# define UF_VERSION 2 /* 2-byte undofile version number */ +# define UF_VERSION_CRYPT 0x8002 /* idem, encrypted */ + +/* extra fields for header */ +# define UF_LAST_SAVE_NR 1 + +/* extra fields for uhp */ +# define UHP_SAVE_NR 1 + +static char_u e_not_open[] = N_("E828: Cannot open undo file for writing: %s"); + +/* + * Compute the hash for the current buffer text into hash[UNDO_HASH_SIZE]. + */ +void u_compute_hash(char_u *hash) +{ + context_sha256_T ctx; + linenr_T lnum; + char_u *p; + + sha256_start(&ctx); + for (lnum = 1; lnum <= curbuf->b_ml.ml_line_count; ++lnum) { + p = ml_get(lnum); + sha256_update(&ctx, p, (uint32_t)(STRLEN(p) + 1)); + } + sha256_finish(&ctx, hash); +} + +/* + * Return an allocated string of the full path of the target undofile. + * When "reading" is TRUE find the file to read, go over all directories in + * 'undodir'. + * When "reading" is FALSE use the first name where the directory exists. + * Returns NULL when there is no place to write or no file to read. + */ +char_u *u_get_undo_file_name(char_u *buf_ffname, int reading) +{ + char_u *dirp; + char_u dir_name[IOSIZE + 1]; + char_u *munged_name = NULL; + char_u *undo_file_name = NULL; + int dir_len; + char_u *p; + char_u *ffname = buf_ffname; +#ifdef HAVE_READLINK + char_u fname_buf[MAXPATHL]; +#endif + + if (ffname == NULL) + return NULL; + +#ifdef HAVE_READLINK + /* Expand symlink in the file name, so that we put the undo file with the + * actual file instead of with the symlink. */ + if (resolve_symlink(ffname, fname_buf) == OK) + ffname = fname_buf; +#endif + + /* Loop over 'undodir'. When reading find the first file that exists. + * When not reading use the first directory that exists or ".". */ + dirp = p_udir; + while (*dirp != NUL) { + dir_len = copy_option_part(&dirp, dir_name, IOSIZE, ","); + if (dir_len == 1 && dir_name[0] == '.') { + /* Use same directory as the ffname, + * "dir/name" -> "dir/.name.un~" */ + undo_file_name = vim_strnsave(ffname, (int)(STRLEN(ffname) + 5)); + if (undo_file_name == NULL) + break; + p = path_tail(undo_file_name); + memmove(p + 1, p, STRLEN(p) + 1); + *p = '.'; + STRCAT(p, ".un~"); + } else { + dir_name[dir_len] = NUL; + if (os_isdir(dir_name)) { + if (munged_name == NULL) { + munged_name = vim_strsave(ffname); + if (munged_name == NULL) + return NULL; + for (p = munged_name; *p != NUL; mb_ptr_adv(p)) + if (vim_ispathsep(*p)) + *p = '%'; + } + undo_file_name = concat_fnames(dir_name, munged_name, TRUE); + } + } + + // When reading check if the file exists. + if (undo_file_name != NULL && + (!reading || os_file_exists(undo_file_name))) { + break; + } + free(undo_file_name); + undo_file_name = NULL; + } + + free(munged_name); + return undo_file_name; +} + +static void corruption_error(char *mesg, char_u *file_name) +{ + EMSG3(_("E825: Corrupted undo file (%s): %s"), mesg, file_name); +} + +static void u_free_uhp(u_header_T *uhp) +{ + u_entry_T *nuep; + u_entry_T *uep; + + uep = uhp->uh_entry; + while (uep != NULL) { + nuep = uep->ue_next; + u_freeentry(uep, uep->ue_size); + uep = nuep; + } + free(uhp); +} + +/* + * Like fwrite() but crypt the bytes when 'key' is set. + * Returns 1 if successful. + */ +static size_t fwrite_crypt(buf_T *buf, char_u *ptr, size_t len, FILE *fp) +{ + char_u *copy; + char_u small_buf[100]; + size_t i; + + if (*buf->b_p_key == NUL) + return fwrite(ptr, len, (size_t)1, fp); + if (len < 100) + copy = small_buf; /* no malloc()/free() for short strings */ + else { + copy = xmalloc(len); + } + crypt_encode(ptr, len, copy); + i = fwrite(copy, len, (size_t)1, fp); + if (copy != small_buf) + free(copy); + return i; +} + +/* + * Read a string of length "len" from "fd". + * When 'key' is set decrypt the bytes. + */ +static char_u *read_string_decrypt(buf_T *buf, FILE *fd, int len) +{ + char_u *ptr; + + ptr = read_string(fd, len); + if (ptr != NULL && *buf->b_p_key != NUL) + crypt_decode(ptr, len); + return ptr; +} + +static int serialize_header(FILE *fp, buf_T *buf, char_u *hash) +{ + int len; + + /* Start writing, first the magic marker and undo info version. */ + if (fwrite(UF_START_MAGIC, (size_t)UF_START_MAGIC_LEN, (size_t)1, fp) != 1) + return FAIL; + + /* If the buffer is encrypted then all text bytes following will be + * encrypted. Numbers and other info is not crypted. */ + if (*buf->b_p_key != NUL) { + char_u *header; + int header_len; + + put_bytes(fp, (long_u)UF_VERSION_CRYPT, 2); + header = prepare_crypt_write(buf, &header_len); + if (header == NULL) + return FAIL; + len = (int)fwrite(header, (size_t)header_len, (size_t)1, fp); + free(header); + if (len != 1) { + crypt_pop_state(); + return FAIL; + } + } else + put_bytes(fp, (long_u)UF_VERSION, 2); + + + /* Write a hash of the buffer text, so that we can verify it is still the + * same when reading the buffer text. */ + if (fwrite(hash, (size_t)UNDO_HASH_SIZE, (size_t)1, fp) != 1) + return FAIL; + + /* buffer-specific data */ + put_bytes(fp, (long_u)buf->b_ml.ml_line_count, 4); + len = buf->b_u_line_ptr != NULL ? (int)STRLEN(buf->b_u_line_ptr) : 0; + put_bytes(fp, (long_u)len, 4); + if (len > 0 && fwrite_crypt(buf, buf->b_u_line_ptr, (size_t)len, fp) != 1) + return FAIL; + put_bytes(fp, (long_u)buf->b_u_line_lnum, 4); + put_bytes(fp, (long_u)buf->b_u_line_colnr, 4); + + /* Undo structures header data */ + put_header_ptr(fp, buf->b_u_oldhead); + put_header_ptr(fp, buf->b_u_newhead); + put_header_ptr(fp, buf->b_u_curhead); + + put_bytes(fp, (long_u)buf->b_u_numhead, 4); + put_bytes(fp, (long_u)buf->b_u_seq_last, 4); + put_bytes(fp, (long_u)buf->b_u_seq_cur, 4); + put_time(fp, buf->b_u_time_cur); + + /* Optional fields. */ + putc(4, fp); + putc(UF_LAST_SAVE_NR, fp); + put_bytes(fp, (long_u)buf->b_u_save_nr_last, 4); + + putc(0, fp); /* end marker */ + + return OK; +} + +static int serialize_uhp(FILE *fp, buf_T *buf, u_header_T *uhp) +{ + int i; + u_entry_T *uep; + + if (put_bytes(fp, (long_u)UF_HEADER_MAGIC, 2) == FAIL) + return FAIL; + + put_header_ptr(fp, uhp->uh_next.ptr); + put_header_ptr(fp, uhp->uh_prev.ptr); + put_header_ptr(fp, uhp->uh_alt_next.ptr); + put_header_ptr(fp, uhp->uh_alt_prev.ptr); + put_bytes(fp, uhp->uh_seq, 4); + serialize_pos(uhp->uh_cursor, fp); + put_bytes(fp, (long_u)uhp->uh_cursor_vcol, 4); + put_bytes(fp, (long_u)uhp->uh_flags, 2); + /* Assume NMARKS will stay the same. */ + for (i = 0; i < NMARKS; ++i) + serialize_pos(uhp->uh_namedm[i], fp); + serialize_visualinfo(&uhp->uh_visual, fp); + put_time(fp, uhp->uh_time); + + /* Optional fields. */ + putc(4, fp); + putc(UHP_SAVE_NR, fp); + put_bytes(fp, (long_u)uhp->uh_save_nr, 4); + + putc(0, fp); /* end marker */ + + /* Write all the entries. */ + for (uep = uhp->uh_entry; uep != NULL; uep = uep->ue_next) { + put_bytes(fp, (long_u)UF_ENTRY_MAGIC, 2); + if (serialize_uep(fp, buf, uep) == FAIL) + return FAIL; + } + put_bytes(fp, (long_u)UF_ENTRY_END_MAGIC, 2); + return OK; +} + +static u_header_T *unserialize_uhp(FILE *fp, char_u *file_name) +{ + u_header_T *uhp; + int i; + u_entry_T *uep, *last_uep; + int c; + int error; + + uhp = xmalloc(sizeof(u_header_T)); + memset(uhp, 0, sizeof(u_header_T)); +#ifdef U_DEBUG + uhp->uh_magic = UH_MAGIC; +#endif + uhp->uh_next.seq = get4c(fp); + uhp->uh_prev.seq = get4c(fp); + uhp->uh_alt_next.seq = get4c(fp); + uhp->uh_alt_prev.seq = get4c(fp); + uhp->uh_seq = get4c(fp); + if (uhp->uh_seq <= 0) { + corruption_error("uh_seq", file_name); + free(uhp); + return NULL; + } + unserialize_pos(&uhp->uh_cursor, fp); + uhp->uh_cursor_vcol = get4c(fp); + uhp->uh_flags = get2c(fp); + for (i = 0; i < NMARKS; ++i) + unserialize_pos(&uhp->uh_namedm[i], fp); + unserialize_visualinfo(&uhp->uh_visual, fp); + uhp->uh_time = get8ctime(fp); + + /* Optional fields. */ + for (;; ) { + int len = getc(fp); + int what; + + if (len == 0) + break; + what = getc(fp); + switch (what) { + case UHP_SAVE_NR: + uhp->uh_save_nr = get4c(fp); + break; + default: + /* field not supported, skip */ + while (--len >= 0) + (void)getc(fp); + } + } + + /* Unserialize the uep list. */ + last_uep = NULL; + while ((c = get2c(fp)) == UF_ENTRY_MAGIC) { + error = FALSE; + uep = unserialize_uep(fp, &error, file_name); + if (last_uep == NULL) + uhp->uh_entry = uep; + else + last_uep->ue_next = uep; + last_uep = uep; + if (uep == NULL || error) { + u_free_uhp(uhp); + return NULL; + } + } + if (c != UF_ENTRY_END_MAGIC) { + corruption_error("entry end", file_name); + u_free_uhp(uhp); + return NULL; + } + + return uhp; +} + +/* + * Serialize "uep" to "fp". + */ +static int serialize_uep(FILE *fp, buf_T *buf, u_entry_T *uep) +{ + int i; + size_t len; + + put_bytes(fp, (long_u)uep->ue_top, 4); + put_bytes(fp, (long_u)uep->ue_bot, 4); + put_bytes(fp, (long_u)uep->ue_lcount, 4); + put_bytes(fp, (long_u)uep->ue_size, 4); + for (i = 0; i < uep->ue_size; ++i) { + len = STRLEN(uep->ue_array[i]); + if (put_bytes(fp, (long_u)len, 4) == FAIL) + return FAIL; + if (len > 0 && fwrite_crypt(buf, uep->ue_array[i], len, fp) != 1) + return FAIL; + } + return OK; +} + +static u_entry_T *unserialize_uep(FILE *fp, int *error, char_u *file_name) +{ + int i; + u_entry_T *uep; + char_u **array; + char_u *line; + int line_len; + + uep = xmalloc(sizeof(u_entry_T)); + memset(uep, 0, sizeof(u_entry_T)); +#ifdef U_DEBUG + uep->ue_magic = UE_MAGIC; +#endif + uep->ue_top = get4c(fp); + uep->ue_bot = get4c(fp); + uep->ue_lcount = get4c(fp); + uep->ue_size = get4c(fp); + if (uep->ue_size > 0) { + array = xmalloc(sizeof(char_u *) * uep->ue_size); + memset(array, 0, sizeof(char_u *) * uep->ue_size); + } else + array = NULL; + uep->ue_array = array; + + for (i = 0; i < uep->ue_size; ++i) { + line_len = get4c(fp); + if (line_len >= 0) + line = read_string_decrypt(curbuf, fp, line_len); + else { + line = NULL; + corruption_error("line length", file_name); + } + if (line == NULL) { + *error = TRUE; + return uep; + } + array[i] = line; + } + return uep; +} + +/* + * Serialize "pos" to "fp". + */ +static void serialize_pos(pos_T pos, FILE *fp) +{ + put_bytes(fp, (long_u)pos.lnum, 4); + put_bytes(fp, (long_u)pos.col, 4); + put_bytes(fp, (long_u)pos.coladd, 4); +} + +/* + * Unserialize the pos_T at the current position in fp. + */ +static void unserialize_pos(pos_T *pos, FILE *fp) +{ + pos->lnum = get4c(fp); + if (pos->lnum < 0) + pos->lnum = 0; + pos->col = get4c(fp); + if (pos->col < 0) + pos->col = 0; + pos->coladd = get4c(fp); + if (pos->coladd < 0) + pos->coladd = 0; +} + +/* + * Serialize "info" to "fp". + */ +static void serialize_visualinfo(visualinfo_T *info, FILE *fp) +{ + serialize_pos(info->vi_start, fp); + serialize_pos(info->vi_end, fp); + put_bytes(fp, (long_u)info->vi_mode, 4); + put_bytes(fp, (long_u)info->vi_curswant, 4); +} + +/* + * Unserialize the visualinfo_T at the current position in fp. + */ +static void unserialize_visualinfo(visualinfo_T *info, FILE *fp) +{ + unserialize_pos(&info->vi_start, fp); + unserialize_pos(&info->vi_end, fp); + info->vi_mode = get4c(fp); + info->vi_curswant = get4c(fp); +} + +/* + * Write the pointer to an undo header. Instead of writing the pointer itself + * we use the sequence number of the header. This is converted back to + * pointers when reading. */ +static void put_header_ptr(FILE *fp, u_header_T *uhp) +{ + put_bytes(fp, (long_u)(uhp != NULL ? uhp->uh_seq : 0), 4); +} + +/* + * Write the undo tree in an undo file. + * When "name" is not NULL, use it as the name of the undo file. + * Otherwise use buf->b_ffname to generate the undo file name. + * "buf" must never be null, buf->b_ffname is used to obtain the original file + * permissions. + * "forceit" is TRUE for ":wundo!", FALSE otherwise. + * "hash[UNDO_HASH_SIZE]" must be the hash value of the buffer text. + */ +void u_write_undo(char_u *name, int forceit, buf_T *buf, char_u *hash) +{ + u_header_T *uhp; + char_u *file_name; + int mark; +#ifdef U_DEBUG + int headers_written = 0; +#endif + int fd; + FILE *fp = NULL; + int perm; + int write_ok = FALSE; + int do_crypt = FALSE; + + if (name == NULL) { + file_name = u_get_undo_file_name(buf->b_ffname, FALSE); + if (file_name == NULL) { + if (p_verbose > 0) { + verbose_enter(); + smsg((char_u *) + _("Cannot write undo file in any directory in 'undodir'")); + verbose_leave(); + } + return; + } + } else + file_name = name; + + /* + * Decide about the permission to use for the undo file. If the buffer + * has a name use the permission of the original file. Otherwise only + * allow the user to access the undo file. + */ + perm = 0600; + if (buf->b_ffname != NULL) { + perm = os_getperm(buf->b_ffname); + if (perm < 0) { + perm = 0600; + } + } + + /* strip any s-bit */ + perm = perm & 0777; + + /* If the undo file already exists, verify that it actually is an undo + * file, and delete it. */ + if (os_file_exists(file_name)) { + if (name == NULL || !forceit) { + /* Check we can read it and it's an undo file. */ + fd = mch_open((char *)file_name, O_RDONLY, 0); + if (fd < 0) { + if (name != NULL || p_verbose > 0) { + if (name == NULL) + verbose_enter(); + smsg((char_u *) + _("Will not overwrite with undo file, cannot read: %s"), + file_name); + if (name == NULL) + verbose_leave(); + } + goto theend; + } else { + char_u mbuf[UF_START_MAGIC_LEN]; + int len; + + len = read_eintr(fd, mbuf, UF_START_MAGIC_LEN); + close(fd); + if (len < UF_START_MAGIC_LEN + || memcmp(mbuf, UF_START_MAGIC, UF_START_MAGIC_LEN) != 0) { + if (name != NULL || p_verbose > 0) { + if (name == NULL) + verbose_enter(); + smsg((char_u *) + _("Will not overwrite, this is not an undo file: %s"), + file_name); + if (name == NULL) + verbose_leave(); + } + goto theend; + } + } + } + os_remove((char *)file_name); + } + + /* If there is no undo information at all, quit here after deleting any + * existing undo file. */ + if (buf->b_u_numhead == 0 && buf->b_u_line_ptr == NULL) { + if (p_verbose > 0) + verb_msg((char_u *)_("Skipping undo file write, nothing to undo")); + goto theend; + } + + fd = mch_open((char *)file_name, + O_CREAT|O_WRONLY|O_EXCL|O_NOFOLLOW, perm); + if (fd < 0) { + EMSG2(_(e_not_open), file_name); + goto theend; + } + (void)os_setperm(file_name, perm); + if (p_verbose > 0) { + verbose_enter(); + smsg((char_u *)_("Writing undo file: %s"), file_name); + verbose_leave(); + } + +#ifdef U_DEBUG + /* Check there is no problem in undo info before writing. */ + u_check(FALSE); +#endif + +#ifdef UNIX + /* + * Try to set the group of the undo file same as the original file. If + * this fails, set the protection bits for the group same as the + * protection bits for others. + */ + FileInfo file_info_old; + FileInfo file_info_new; + if (os_get_file_info((char *)buf->b_ffname, &file_info_old) + && os_get_file_info((char *)file_name, &file_info_new) + && file_info_old.stat.st_gid != file_info_new.stat.st_gid +# ifdef HAVE_FCHOWN /* sequent-ptx lacks fchown() */ + && fchown(fd, (uid_t)-1, file_info_old.stat.st_gid) != 0 +# endif + ) { + os_setperm(file_name, (perm & 0707) | ((perm & 07) << 3)); + } +# ifdef HAVE_SELINUX + if (buf->b_ffname != NULL) + mch_copy_sec(buf->b_ffname, file_name); +# endif +#endif + + fp = fdopen(fd, "w"); + if (fp == NULL) { + EMSG2(_(e_not_open), file_name); + close(fd); + os_remove((char *)file_name); + goto theend; + } + + /* Undo must be synced. */ + u_sync(TRUE); + + /* + * Write the header. + */ + if (serialize_header(fp, buf, hash) == FAIL) + goto write_error; + if (*buf->b_p_key != NUL) + do_crypt = TRUE; + + /* + * Iteratively serialize UHPs and their UEPs from the top down. + */ + mark = ++lastmark; + uhp = buf->b_u_oldhead; + while (uhp != NULL) { + /* Serialize current UHP if we haven't seen it */ + if (uhp->uh_walk != mark) { + uhp->uh_walk = mark; +#ifdef U_DEBUG + ++headers_written; +#endif + if (serialize_uhp(fp, buf, uhp) == FAIL) + goto write_error; + } + + /* Now walk through the tree - algorithm from undo_time(). */ + if (uhp->uh_prev.ptr != NULL && uhp->uh_prev.ptr->uh_walk != mark) + uhp = uhp->uh_prev.ptr; + else if (uhp->uh_alt_next.ptr != NULL + && uhp->uh_alt_next.ptr->uh_walk != mark) + uhp = uhp->uh_alt_next.ptr; + else if (uhp->uh_next.ptr != NULL && uhp->uh_alt_prev.ptr == NULL + && uhp->uh_next.ptr->uh_walk != mark) + uhp = uhp->uh_next.ptr; + else if (uhp->uh_alt_prev.ptr != NULL) + uhp = uhp->uh_alt_prev.ptr; + else + uhp = uhp->uh_next.ptr; + } + + if (put_bytes(fp, (long_u)UF_HEADER_END_MAGIC, 2) == OK) + write_ok = TRUE; +#ifdef U_DEBUG + if (headers_written != buf->b_u_numhead) { + EMSGN("Written %" PRId64 " headers, ...", headers_written); + EMSGN("... but numhead is %" PRId64, buf->b_u_numhead); + } +#endif + +write_error: + fclose(fp); + if (!write_ok) + EMSG2(_("E829: write error in undo file: %s"), file_name); + +#ifdef HAVE_ACL + if (buf->b_ffname != NULL) { + vim_acl_T acl; + + /* For systems that support ACL: get the ACL from the original file. */ + acl = mch_get_acl(buf->b_ffname); + mch_set_acl(file_name, acl); + mch_free_acl(acl); + } +#endif + +theend: + if (do_crypt) + crypt_pop_state(); + if (file_name != name) + free(file_name); +} + +/* + * Load the undo tree from an undo file. + * If "name" is not NULL use it as the undo file name. This also means being + * a bit more verbose. + * Otherwise use curbuf->b_ffname to generate the undo file name. + * "hash[UNDO_HASH_SIZE]" must be the hash value of the buffer text. + */ +void u_read_undo(char_u *name, char_u *hash, char_u *orig_name) +{ + char_u *file_name; + FILE *fp; + long version, str_len; + char_u *line_ptr = NULL; + linenr_T line_lnum; + colnr_T line_colnr; + linenr_T line_count; + int num_head = 0; + long old_header_seq, new_header_seq, cur_header_seq; + long seq_last, seq_cur; + long last_save_nr = 0; + short old_idx = -1, new_idx = -1, cur_idx = -1; + long num_read_uhps = 0; + time_t seq_time; + int i, j; + int c; + u_header_T *uhp; + u_header_T **uhp_table = NULL; + char_u read_hash[UNDO_HASH_SIZE]; + char_u magic_buf[UF_START_MAGIC_LEN]; +#ifdef U_DEBUG + int *uhp_table_used; +#endif + int do_decrypt = FALSE; + + if (name == NULL) { + file_name = u_get_undo_file_name(curbuf->b_ffname, TRUE); + if (file_name == NULL) + return; + +#ifdef UNIX + /* For safety we only read an undo file if the owner is equal to the + * owner of the text file or equal to the current user. */ + FileInfo file_info_orig; + FileInfo file_info_undo; + if (os_get_file_info((char *)orig_name, &file_info_orig) + && os_get_file_info((char *)file_name, &file_info_undo) + && file_info_orig.stat.st_uid != file_info_undo.stat.st_uid + && file_info_undo.stat.st_uid != getuid()) { + if (p_verbose > 0) { + verbose_enter(); + smsg((char_u *)_("Not reading undo file, owner differs: %s"), + file_name); + verbose_leave(); + } + return; + } +#endif + } else + file_name = name; + + if (p_verbose > 0) { + verbose_enter(); + smsg((char_u *)_("Reading undo file: %s"), file_name); + verbose_leave(); + } + + fp = mch_fopen((char *)file_name, "r"); + if (fp == NULL) { + if (name != NULL || p_verbose > 0) + EMSG2(_("E822: Cannot open undo file for reading: %s"), file_name); + goto error; + } + + /* + * Read the undo file header. + */ + if (fread(magic_buf, UF_START_MAGIC_LEN, 1, fp) != 1 + || memcmp(magic_buf, UF_START_MAGIC, UF_START_MAGIC_LEN) != 0) { + EMSG2(_("E823: Not an undo file: %s"), file_name); + goto error; + } + version = get2c(fp); + if (version == UF_VERSION_CRYPT) { + if (*curbuf->b_p_key == NUL) { + EMSG2(_("E832: Non-encrypted file has encrypted undo file: %s"), + file_name); + goto error; + } + if (prepare_crypt_read(fp) == FAIL) { + EMSG2(_("E826: Undo file decryption failed: %s"), file_name); + goto error; + } + do_decrypt = TRUE; + } else if (version != UF_VERSION) { + EMSG2(_("E824: Incompatible undo file: %s"), file_name); + goto error; + } + + if (fread(read_hash, UNDO_HASH_SIZE, 1, fp) != 1) { + corruption_error("hash", file_name); + goto error; + } + line_count = (linenr_T)get4c(fp); + if (memcmp(hash, read_hash, UNDO_HASH_SIZE) != 0 + || line_count != curbuf->b_ml.ml_line_count) { + if (p_verbose > 0 || name != NULL) { + if (name == NULL) + verbose_enter(); + give_warning((char_u *) + _("File contents changed, cannot use undo info"), TRUE); + if (name == NULL) + verbose_leave(); + } + goto error; + } + + /* Read undo data for "U" command. */ + str_len = get4c(fp); + if (str_len < 0) + goto error; + if (str_len > 0) + line_ptr = read_string_decrypt(curbuf, fp, str_len); + line_lnum = (linenr_T)get4c(fp); + line_colnr = (colnr_T)get4c(fp); + if (line_lnum < 0 || line_colnr < 0) { + corruption_error("line lnum/col", file_name); + goto error; + } + + /* Begin general undo data */ + old_header_seq = get4c(fp); + new_header_seq = get4c(fp); + cur_header_seq = get4c(fp); + num_head = get4c(fp); + seq_last = get4c(fp); + seq_cur = get4c(fp); + seq_time = get8ctime(fp); + + /* Optional header fields. */ + for (;; ) { + int len = getc(fp); + int what; + + if (len == 0 || len == EOF) + break; + what = getc(fp); + switch (what) { + case UF_LAST_SAVE_NR: + last_save_nr = get4c(fp); + break; + default: + /* field not supported, skip */ + while (--len >= 0) + (void)getc(fp); + } + } + + /* uhp_table will store the freshly created undo headers we allocate + * until we insert them into curbuf. The table remains sorted by the + * sequence numbers of the headers. + * When there are no headers uhp_table is NULL. */ + if (num_head > 0) { + uhp_table = xmalloc(num_head * sizeof(u_header_T *)); + } + + while ((c = get2c(fp)) == UF_HEADER_MAGIC) { + if (num_read_uhps >= num_head) { + corruption_error("num_head too small", file_name); + goto error; + } + + uhp = unserialize_uhp(fp, file_name); + if (uhp == NULL) + goto error; + uhp_table[num_read_uhps++] = uhp; + } + + if (num_read_uhps != num_head) { + corruption_error("num_head", file_name); + goto error; + } + if (c != UF_HEADER_END_MAGIC) { + corruption_error("end marker", file_name); + goto error; + } + +#ifdef U_DEBUG + size_t amount = num_head * sizeof(int) + 1; + uhp_table_used = xmalloc(amount); + memset(uhp_table_used, 0, amount); +# define SET_FLAG(j) ++ uhp_table_used[j] +#else +# define SET_FLAG(j) +#endif + + /* We have put all of the headers into a table. Now we iterate through the + * table and swizzle each sequence number we have stored in uh_*_seq into + * a pointer corresponding to the header with that sequence number. */ + for (i = 0; i < num_head; i++) { + uhp = uhp_table[i]; + if (uhp == NULL) + continue; + for (j = 0; j < num_head; j++) + if (uhp_table[j] != NULL && i != j + && uhp_table[i]->uh_seq == uhp_table[j]->uh_seq) { + corruption_error("duplicate uh_seq", file_name); + goto error; + } + for (j = 0; j < num_head; j++) + if (uhp_table[j] != NULL + && uhp_table[j]->uh_seq == uhp->uh_next.seq) { + uhp->uh_next.ptr = uhp_table[j]; + SET_FLAG(j); + break; + } + for (j = 0; j < num_head; j++) + if (uhp_table[j] != NULL + && uhp_table[j]->uh_seq == uhp->uh_prev.seq) { + uhp->uh_prev.ptr = uhp_table[j]; + SET_FLAG(j); + break; + } + for (j = 0; j < num_head; j++) + if (uhp_table[j] != NULL + && uhp_table[j]->uh_seq == uhp->uh_alt_next.seq) { + uhp->uh_alt_next.ptr = uhp_table[j]; + SET_FLAG(j); + break; + } + for (j = 0; j < num_head; j++) + if (uhp_table[j] != NULL + && uhp_table[j]->uh_seq == uhp->uh_alt_prev.seq) { + uhp->uh_alt_prev.ptr = uhp_table[j]; + SET_FLAG(j); + break; + } + if (old_header_seq > 0 && old_idx < 0 && uhp->uh_seq == old_header_seq) { + old_idx = i; + SET_FLAG(i); + } + if (new_header_seq > 0 && new_idx < 0 && uhp->uh_seq == new_header_seq) { + new_idx = i; + SET_FLAG(i); + } + if (cur_header_seq > 0 && cur_idx < 0 && uhp->uh_seq == cur_header_seq) { + cur_idx = i; + SET_FLAG(i); + } + } + + /* Now that we have read the undo info successfully, free the current undo + * info and use the info from the file. */ + u_blockfree(curbuf); + curbuf->b_u_oldhead = old_idx < 0 ? NULL : uhp_table[old_idx]; + curbuf->b_u_newhead = new_idx < 0 ? NULL : uhp_table[new_idx]; + curbuf->b_u_curhead = cur_idx < 0 ? NULL : uhp_table[cur_idx]; + curbuf->b_u_line_ptr = line_ptr; + curbuf->b_u_line_lnum = line_lnum; + curbuf->b_u_line_colnr = line_colnr; + curbuf->b_u_numhead = num_head; + curbuf->b_u_seq_last = seq_last; + curbuf->b_u_seq_cur = seq_cur; + curbuf->b_u_time_cur = seq_time; + curbuf->b_u_save_nr_last = last_save_nr; + curbuf->b_u_save_nr_cur = last_save_nr; + + curbuf->b_u_synced = TRUE; + free(uhp_table); + +#ifdef U_DEBUG + for (i = 0; i < num_head; ++i) + if (uhp_table_used[i] == 0) + EMSGN("uhp_table entry %" PRId64 " not used, leaking memory", i); + free(uhp_table_used); + u_check(TRUE); +#endif + + if (name != NULL) + smsg((char_u *)_("Finished reading undo file %s"), file_name); + goto theend; + +error: + free(line_ptr); + if (uhp_table != NULL) { + for (i = 0; i < num_read_uhps; i++) + if (uhp_table[i] != NULL) + u_free_uhp(uhp_table[i]); + free(uhp_table); + } + +theend: + if (do_decrypt) + crypt_pop_state(); + if (fp != NULL) + fclose(fp); + if (file_name != name) + free(file_name); + return; +} + + + +/* + * If 'cpoptions' contains 'u': Undo the previous undo or redo (vi compatible). + * If 'cpoptions' does not contain 'u': Always undo. + */ +void u_undo(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(TRUE); + 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(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(int startcount) +{ + int count = startcount; + + if (!undo_allowed()) + return; + + u_newcount = 0; + u_oldcount = 0; + if (curbuf->b_ml.ml_flags & ML_EMPTY) + u_oldcount = -1; + while (count--) { + /* Do the change warning now, so that it triggers FileChangedRO when + * needed. This may cause the file to be reloaded, that must happen + * before we do anything, because it may change curbuf->b_u_curhead + * and more. */ + change_warning(0); + + if (undo_undoes) { + if (curbuf->b_u_curhead == NULL) /* first undo */ + curbuf->b_u_curhead = curbuf->b_u_newhead; + else if (get_undolevel() > 0) /* multi level undo */ + /* get next undo */ + curbuf->b_u_curhead = curbuf->b_u_curhead->uh_next.ptr; + /* 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(); + if (count == startcount - 1) { + MSG(_("Already at oldest change")); + return; + } + break; + } + + u_undoredo(TRUE); + } else { + if (curbuf->b_u_curhead == NULL || get_undolevel() <= 0) { + beep_flush(); /* nothing to redo */ + if (count == startcount - 1) { + MSG(_("Already at newest change")); + return; + } + break; + } + + u_undoredo(FALSE); + + /* Advance for next redo. Set "newhead" when at the end of the + * redoable changes. */ + if (curbuf->b_u_curhead->uh_prev.ptr == NULL) + curbuf->b_u_newhead = curbuf->b_u_curhead; + curbuf->b_u_curhead = curbuf->b_u_curhead->uh_prev.ptr; + } + } + u_undo_end(undo_undoes, FALSE); +} + +/* + * Undo or redo over the timeline. + * When "step" is negative go back in time, otherwise goes forward in time. + * When "sec" is FALSE make "step" steps, when "sec" is TRUE use "step" as + * seconds. + * When "file" is TRUE use "step" as a number of file writes. + * When "absolute" is TRUE use "step" as the sequence number to jump to. + * "sec" must be FALSE then. + */ +void undo_time(long step, int sec, int file, int absolute) +{ + long target; + long closest; + long closest_start; + long closest_seq = 0; + long val; + u_header_T *uhp; + u_header_T *last; + int mark; + int nomark; + int round; + int dosec = sec; + int dofile = file; + int above = FALSE; + int did_undo = TRUE; + + /* First make sure the current undoable change is synced. */ + if (curbuf->b_u_synced == FALSE) + u_sync(TRUE); + + u_newcount = 0; + u_oldcount = 0; + if (curbuf->b_ml.ml_flags & ML_EMPTY) + u_oldcount = -1; + + /* "target" is the node below which we want to be. + * Init "closest" to a value we can't reach. */ + if (absolute) { + target = step; + closest = -1; + } else { + /* When doing computations with time_t subtract starttime, because + * time_t converted to a long may result in a wrong number. */ + if (dosec) + target = (long)(curbuf->b_u_time_cur - starttime) + step; + else if (dofile) { + if (step < 0) { + /* Going back to a previous write. If there were changes after + * the last write, count that as moving one file-write, so + * that ":earlier 1f" undoes all changes since the last save. */ + uhp = curbuf->b_u_curhead; + if (uhp != NULL) + uhp = uhp->uh_next.ptr; + else + uhp = curbuf->b_u_newhead; + if (uhp != NULL && uhp->uh_save_nr != 0) + /* "uh_save_nr" was set in the last block, that means + * there were no changes since the last write */ + target = curbuf->b_u_save_nr_cur + step; + else + /* count the changes since the last write as one step */ + target = curbuf->b_u_save_nr_cur + step + 1; + if (target <= 0) + /* Go to before first write: before the oldest change. Use + * the sequence number for that. */ + dofile = FALSE; + } else { + /* Moving forward to a newer write. */ + target = curbuf->b_u_save_nr_cur + step; + if (target > curbuf->b_u_save_nr_last) { + /* Go to after last write: after the latest change. Use + * the sequence number for that. */ + target = curbuf->b_u_seq_last + 1; + dofile = FALSE; + } + } + } else + target = curbuf->b_u_seq_cur + step; + if (step < 0) { + if (target < 0) + target = 0; + closest = -1; + } else { + if (dosec) + closest = (long)(time(NULL) - starttime + 1); + else if (dofile) + closest = curbuf->b_u_save_nr_last + 2; + else + closest = curbuf->b_u_seq_last + 2; + if (target >= closest) + target = closest - 1; + } + } + closest_start = closest; + closest_seq = curbuf->b_u_seq_cur; + + /* + * May do this twice: + * 1. Search for "target", update "closest" to the best match found. + * 2. If "target" not found search for "closest". + * + * When using the closest time we use the sequence number in the second + * round, because there may be several entries with the same time. + */ + for (round = 1; round <= 2; ++round) { + /* Find the path from the current state to where we want to go. The + * desired state can be anywhere in the undo tree, need to go all over + * it. We put "nomark" in uh_walk where we have been without success, + * "mark" where it could possibly be. */ + mark = ++lastmark; + nomark = ++lastmark; + + if (curbuf->b_u_curhead == NULL) /* at leaf of the tree */ + uhp = curbuf->b_u_newhead; + else + uhp = curbuf->b_u_curhead; + + while (uhp != NULL) { + uhp->uh_walk = mark; + if (dosec) + val = (long)(uhp->uh_time - starttime); + else if (dofile) + val = uhp->uh_save_nr; + else + val = uhp->uh_seq; + + if (round == 1 && !(dofile && val == 0)) { + /* Remember the header that is closest to the target. + * It must be at least in the right direction (checked with + * "b_u_seq_cur"). When the timestamp is equal find the + * highest/lowest sequence number. */ + if ((step < 0 ? uhp->uh_seq <= curbuf->b_u_seq_cur + : uhp->uh_seq > curbuf->b_u_seq_cur) + && ((dosec && val == closest) + ? (step < 0 + ? uhp->uh_seq < closest_seq + : uhp->uh_seq > closest_seq) + : closest == closest_start + || (val > target + ? (closest > target + ? val - target <= closest - target + : val - target <= target - closest) + : (closest > target + ? target - val <= closest - target + : target - val <= target - closest)))) { + closest = val; + closest_seq = uhp->uh_seq; + } + } + + /* Quit searching when we found a match. But when searching for a + * time we need to continue looking for the best uh_seq. */ + if (target == val && !dosec) { + target = uhp->uh_seq; + break; + } + + /* go down in the tree if we haven't been there */ + if (uhp->uh_prev.ptr != NULL && uhp->uh_prev.ptr->uh_walk != nomark + && uhp->uh_prev.ptr->uh_walk != mark) + uhp = uhp->uh_prev.ptr; + + /* go to alternate branch if we haven't been there */ + else if (uhp->uh_alt_next.ptr != NULL + && uhp->uh_alt_next.ptr->uh_walk != nomark + && uhp->uh_alt_next.ptr->uh_walk != mark) + uhp = uhp->uh_alt_next.ptr; + + /* go up in the tree if we haven't been there and we are at the + * start of alternate branches */ + else if (uhp->uh_next.ptr != NULL && uhp->uh_alt_prev.ptr == NULL + && uhp->uh_next.ptr->uh_walk != nomark + && uhp->uh_next.ptr->uh_walk != mark) { + /* If still at the start we don't go through this change. */ + if (uhp == curbuf->b_u_curhead) + uhp->uh_walk = nomark; + uhp = uhp->uh_next.ptr; + } else { + /* need to backtrack; mark this node as useless */ + uhp->uh_walk = nomark; + if (uhp->uh_alt_prev.ptr != NULL) + uhp = uhp->uh_alt_prev.ptr; + else + uhp = uhp->uh_next.ptr; + } + } + + if (uhp != NULL) /* found it */ + break; + + if (absolute) { + EMSGN(_("E830: Undo number %" PRId64 " not found"), step); + return; + } + + if (closest == closest_start) { + if (step < 0) + MSG(_("Already at oldest change")); + else + MSG(_("Already at newest change")); + return; + } + + target = closest_seq; + dosec = FALSE; + dofile = FALSE; + if (step < 0) + above = TRUE; /* stop above the header */ + } + + /* If we found it: Follow the path to go to where we want to be. */ + if (uhp != NULL) { + /* + * First go up the tree as much as needed. + */ + while (!got_int) { + /* Do the change warning now, for the same reason as above. */ + change_warning(0); + + uhp = curbuf->b_u_curhead; + if (uhp == NULL) + uhp = curbuf->b_u_newhead; + else + uhp = uhp->uh_next.ptr; + if (uhp == NULL || uhp->uh_walk != mark + || (uhp->uh_seq == target && !above)) + break; + curbuf->b_u_curhead = uhp; + u_undoredo(TRUE); + uhp->uh_walk = nomark; /* don't go back down here */ + } + + /* + * And now go down the tree (redo), branching off where needed. + */ + while (!got_int) { + /* Do the change warning now, for the same reason as above. */ + change_warning(0); + + uhp = curbuf->b_u_curhead; + if (uhp == NULL) + break; + + /* Go back to the first branch with a mark. */ + while (uhp->uh_alt_prev.ptr != NULL + && uhp->uh_alt_prev.ptr->uh_walk == mark) + uhp = uhp->uh_alt_prev.ptr; + + /* Find the last branch with a mark, that's the one. */ + last = uhp; + while (last->uh_alt_next.ptr != NULL + && last->uh_alt_next.ptr->uh_walk == mark) + last = last->uh_alt_next.ptr; + if (last != uhp) { + /* Make the used branch the first entry in the list of + * alternatives to make "u" and CTRL-R take this branch. */ + while (uhp->uh_alt_prev.ptr != NULL) + uhp = uhp->uh_alt_prev.ptr; + if (last->uh_alt_next.ptr != NULL) + last->uh_alt_next.ptr->uh_alt_prev.ptr = + last->uh_alt_prev.ptr; + last->uh_alt_prev.ptr->uh_alt_next.ptr = last->uh_alt_next.ptr; + last->uh_alt_prev.ptr = NULL; + last->uh_alt_next.ptr = uhp; + uhp->uh_alt_prev.ptr = last; + + if (curbuf->b_u_oldhead == uhp) + curbuf->b_u_oldhead = last; + uhp = last; + if (uhp->uh_next.ptr != NULL) + uhp->uh_next.ptr->uh_prev.ptr = uhp; + } + curbuf->b_u_curhead = uhp; + + if (uhp->uh_walk != mark) + break; /* must have reached the target */ + + /* Stop when going backwards in time and didn't find the exact + * header we were looking for. */ + if (uhp->uh_seq == target && above) { + curbuf->b_u_seq_cur = target - 1; + break; + } + + u_undoredo(FALSE); + + /* Advance "curhead" to below the header we last used. If it + * becomes NULL then we need to set "newhead" to this leaf. */ + if (uhp->uh_prev.ptr == NULL) + curbuf->b_u_newhead = uhp; + curbuf->b_u_curhead = uhp->uh_prev.ptr; + did_undo = FALSE; + + if (uhp->uh_seq == target) /* found it! */ + break; + + uhp = uhp->uh_prev.ptr; + if (uhp == NULL || uhp->uh_walk != mark) { + /* Need to redo more but can't find it... */ + EMSG2(_(e_intern2), "undo_time()"); + break; + } + } + } + u_undo_end(did_undo, absolute); +} + +/* + * 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. + * + * When "undo" is TRUE we go up in the tree, when FALSE we go down. + */ +static void u_undoredo(int undo) +{ + 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]; + visualinfo_T visualinfo; + int empty_buffer; /* buffer became empty */ + u_header_T *curhead = curbuf->b_u_curhead; + + /* Don't want autocommands using the undo structures here, they are + * invalid till the end. */ + block_autocmds(); + +#ifdef U_DEBUG + u_check(FALSE); +#endif + old_flags = 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 + */ + memmove(namedm, curbuf->b_namedm, sizeof(pos_T) * NMARKS); + visualinfo = curbuf->b_visual; + 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 = 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) { + unblock_autocmds(); + 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 = curhead->uh_cursor.lnum; + if (lnum >= top && lnum <= top + newsize + 1) { + curwin->w_cursor = 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) { + newarray = xmalloc(sizeof(char_u *) * oldsize); + /* 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); + free(uep->ue_array[i]); + } + free((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; + } + + curhead->uh_entry = newlist; + 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 + unchanged(curbuf, FALSE); + + /* + * restore marks from before undo/redo + */ + for (i = 0; i < NMARKS; ++i) + if (curhead->uh_namedm[i].lnum != 0) { + curbuf->b_namedm[i] = curhead->uh_namedm[i]; + curhead->uh_namedm[i] = namedm[i]; + } + if (curhead->uh_visual.vi_start.lnum != 0) { + curbuf->b_visual = curhead->uh_visual; + curhead->uh_visual = visualinfo; + } + + /* + * 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 (curhead->uh_cursor.lnum + 1 == curwin->w_cursor.lnum + && curwin->w_cursor.lnum > 1) + --curwin->w_cursor.lnum; + if (curwin->w_cursor.lnum <= curbuf->b_ml.ml_line_count) { + if (curhead->uh_cursor.lnum == curwin->w_cursor.lnum) { + curwin->w_cursor.col = curhead->uh_cursor.col; + if (virtual_active() && curhead->uh_cursor_vcol >= 0) + coladvance((colnr_T)curhead->uh_cursor_vcol); + else + curwin->w_cursor.coladd = 0; + } else + 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; + curwin->w_cursor.coladd = 0; + } + + /* Make sure the cursor is on an existing line and column. */ + check_cursor(); + + /* Remember where we are for "g-" and ":earlier 10s". */ + curbuf->b_u_seq_cur = curhead->uh_seq; + if (undo) + /* We are below the previous undo. However, to make ":earlier 1s" + * work we compute this as being just above the just undone change. */ + --curbuf->b_u_seq_cur; + + /* Remember where we are for ":earlier 1f" and ":later 1f". */ + if (curhead->uh_save_nr != 0) { + if (undo) + curbuf->b_u_save_nr_cur = curhead->uh_save_nr - 1; + else + curbuf->b_u_save_nr_cur = curhead->uh_save_nr; + } + + /* The timestamp can be the same for multiple changes, just use the one of + * the undone/redone change. */ + curbuf->b_u_time_cur = curhead->uh_time; + + unblock_autocmds(); +#ifdef U_DEBUG + u_check(FALSE); +#endif +} + +/* + * 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 ( + int did_undo, /* just did an undo */ + int absolute /* used ":undo N" */ +) +{ + char *msgstr; + u_header_T *uhp; + char_u msgbuf[80]; + + if ((fdo_flags & FDO_UNDO) && KeyTyped) + foldOpenCursor(); + + if (global_busy /* no messages now, wait until global is finished */ + || !messaging()) /* 'lazyredraw' set, don't do messages now */ + return; + + if (curbuf->b_ml.ml_flags & ML_EMPTY) + --u_newcount; + + u_oldcount -= u_newcount; + if (u_oldcount == -1) + msgstr = N_("more line"); + else if (u_oldcount < 0) + msgstr = N_("more lines"); + else if (u_oldcount == 1) + msgstr = N_("line less"); + else if (u_oldcount > 1) + msgstr = N_("fewer lines"); + else { + u_oldcount = u_newcount; + if (u_newcount == 1) + msgstr = N_("change"); + else + msgstr = N_("changes"); + } + + if (curbuf->b_u_curhead != NULL) { + /* For ":undo N" we prefer a "after #N" message. */ + if (absolute && curbuf->b_u_curhead->uh_next.ptr != NULL) { + uhp = curbuf->b_u_curhead->uh_next.ptr; + did_undo = FALSE; + } else if (did_undo) + uhp = curbuf->b_u_curhead; + else + uhp = curbuf->b_u_curhead->uh_next.ptr; + } else + uhp = curbuf->b_u_newhead; + + if (uhp == NULL) + *msgbuf = NUL; + else + u_add_time(msgbuf, sizeof(msgbuf), uhp->uh_time); + + { + win_T *wp; + + FOR_ALL_WINDOWS(wp) + { + if (wp->w_buffer == curbuf && wp->w_p_cole > 0) + redraw_win_later(wp, NOT_VALID); + } + } + + smsg((char_u *)_("%" PRId64 " %s; %s #%" PRId64 " %s"), + u_oldcount < 0 ? (int64_t)-u_oldcount : (int64_t)u_oldcount, + _(msgstr), + did_undo ? _("before") : _("after"), + uhp == NULL ? (int64_t)0L : (int64_t)uhp->uh_seq, + msgbuf); +} + +/* + * u_sync: stop adding to the current entry list + */ +void +u_sync ( + int force /* Also sync when no_u_sync is set. */ +) +{ + /* Skip it when already synced or syncing is disabled. */ + if (curbuf->b_u_synced || (!force && no_u_sync > 0)) + return; + if (get_undolevel() < 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; + } +} + +/* + * ":undolist": List the leafs of the undo tree + */ +void ex_undolist(exarg_T *eap) +{ + garray_T ga; + u_header_T *uhp; + int mark; + int nomark; + int changes = 1; + int i; + + /* + * 1: walk the tree to find all leafs, put the info in "ga". + * 2: sort the lines + * 3: display the list + */ + mark = ++lastmark; + nomark = ++lastmark; + ga_init(&ga, (int)sizeof(char *), 20); + + uhp = curbuf->b_u_oldhead; + while (uhp != NULL) { + if (uhp->uh_prev.ptr == NULL && uhp->uh_walk != nomark + && uhp->uh_walk != mark) { + ga_grow(&ga, 1); + vim_snprintf((char *)IObuff, IOSIZE, "%6ld %7ld ", + uhp->uh_seq, changes); + u_add_time(IObuff + STRLEN(IObuff), IOSIZE - STRLEN(IObuff), + uhp->uh_time); + if (uhp->uh_save_nr > 0) { + while (STRLEN(IObuff) < 33) + STRCAT(IObuff, " "); + vim_snprintf_add((char *)IObuff, IOSIZE, + " %3ld", uhp->uh_save_nr); + } + ((char_u **)(ga.ga_data))[ga.ga_len++] = vim_strsave(IObuff); + } + + uhp->uh_walk = mark; + + /* go down in the tree if we haven't been there */ + if (uhp->uh_prev.ptr != NULL && uhp->uh_prev.ptr->uh_walk != nomark + && uhp->uh_prev.ptr->uh_walk != mark) { + uhp = uhp->uh_prev.ptr; + ++changes; + } + /* go to alternate branch if we haven't been there */ + else if (uhp->uh_alt_next.ptr != NULL + && uhp->uh_alt_next.ptr->uh_walk != nomark + && uhp->uh_alt_next.ptr->uh_walk != mark) + uhp = uhp->uh_alt_next.ptr; + + /* go up in the tree if we haven't been there and we are at the + * start of alternate branches */ + else if (uhp->uh_next.ptr != NULL && uhp->uh_alt_prev.ptr == NULL + && uhp->uh_next.ptr->uh_walk != nomark + && uhp->uh_next.ptr->uh_walk != mark) { + uhp = uhp->uh_next.ptr; + --changes; + } else { + /* need to backtrack; mark this node as done */ + uhp->uh_walk = nomark; + if (uhp->uh_alt_prev.ptr != NULL) + uhp = uhp->uh_alt_prev.ptr; + else { + uhp = uhp->uh_next.ptr; + --changes; + } + } + } + + if (ga.ga_len == 0) + MSG(_("Nothing to undo")); + else { + sort_strings((char_u **)ga.ga_data, ga.ga_len); + + msg_start(); + msg_puts_attr((char_u *)_("number changes when saved"), + hl_attr(HLF_T)); + for (i = 0; i < ga.ga_len && !got_int; ++i) { + msg_putchar('\n'); + if (got_int) + break; + msg_puts(((char_u **)ga.ga_data)[i]); + } + msg_end(); + + ga_clear_strings(&ga); + } +} + +/* + * Put the timestamp of an undo header in "buf[buflen]" in a nice format. + */ +static void u_add_time(char_u *buf, size_t buflen, time_t tt) +{ + struct tm curtime; + + if (time(NULL) - tt >= 100) { + os_localtime_r(&tt, &curtime); + if (time(NULL) - tt < (60L * 60L * 12L)) + /* within 12 hours */ + (void)strftime((char *)buf, buflen, "%H:%M:%S", &curtime); + else + /* longer ago */ + (void)strftime((char *)buf, buflen, "%Y/%m/%d %H:%M:%S", &curtime); + } else + vim_snprintf((char *)buf, buflen, _("%" PRId64 " seconds ago"), + (int64_t)(time(NULL) - tt)); +} + +/* + * ":undojoin": continue adding to the last entry list + */ +void ex_undojoin(exarg_T *eap) +{ + if (curbuf->b_u_newhead == NULL) + return; /* nothing changed before */ + if (curbuf->b_u_curhead != NULL) { + EMSG(_("E790: undojoin is not allowed after undo")); + return; + } + if (!curbuf->b_u_synced) + return; /* already unsynced */ + if (get_undolevel() < 0) + return; /* no entries, nothing to do */ + else { + /* Go back to the last entry */ + curbuf->b_u_curhead = curbuf->b_u_newhead; + curbuf->b_u_synced = FALSE; /* no entries, nothing to do */ + } +} + +/* + * Called after writing or reloading the file and setting b_changed to FALSE. + * Now an undo means that the buffer is modified. + */ +void u_unchanged(buf_T *buf) +{ + u_unch_branch(buf->b_u_oldhead); + buf->b_did_warn = FALSE; +} + +/* + * After reloading a buffer which was saved for 'undoreload': Find the first + * line that was changed and set the cursor there. + */ +void u_find_first_changed(void) +{ + u_header_T *uhp = curbuf->b_u_newhead; + u_entry_T *uep; + linenr_T lnum; + + if (curbuf->b_u_curhead != NULL || uhp == NULL) + return; /* undid something in an autocmd? */ + + /* Check that the last undo block was for the whole file. */ + uep = uhp->uh_entry; + if (uep->ue_top != 0 || uep->ue_bot != 0) + return; + + for (lnum = 1; lnum < curbuf->b_ml.ml_line_count + && lnum <= uep->ue_size; ++lnum) + if (STRCMP(ml_get_buf(curbuf, lnum, FALSE), + uep->ue_array[lnum - 1]) != 0) { + clearpos(&(uhp->uh_cursor)); + uhp->uh_cursor.lnum = lnum; + return; + } + if (curbuf->b_ml.ml_line_count != uep->ue_size) { + /* lines added or deleted at the end, put the cursor there */ + clearpos(&(uhp->uh_cursor)); + uhp->uh_cursor.lnum = lnum; + } +} + +/* + * Increase the write count, store it in the last undo header, what would be + * used for "u". + */ +void u_update_save_nr(buf_T *buf) +{ + u_header_T *uhp; + + ++buf->b_u_save_nr_last; + buf->b_u_save_nr_cur = buf->b_u_save_nr_last; + uhp = buf->b_u_curhead; + if (uhp != NULL) + uhp = uhp->uh_next.ptr; + else + uhp = buf->b_u_newhead; + if (uhp != NULL) + uhp->uh_save_nr = buf->b_u_save_nr_last; +} + +static void u_unch_branch(u_header_T *uhp) +{ + u_header_T *uh; + + for (uh = uhp; uh != NULL; uh = uh->uh_prev.ptr) { + uh->uh_flags |= UH_CHANGED; + if (uh->uh_alt_next.ptr != NULL) + u_unch_branch(uh->uh_alt_next.ptr); /* recursive */ + } +} + +/* + * 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(void) +{ + 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(void) +{ + 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; +} + +/* + * Free one header "uhp" and its entry list and adjust the pointers. + */ +static void +u_freeheader ( + buf_T *buf, + u_header_T *uhp, + u_header_T **uhpp /* if not NULL reset when freeing this header */ +) +{ + u_header_T *uhap; + + /* When there is an alternate redo list free that branch completely, + * because we can never go there. */ + if (uhp->uh_alt_next.ptr != NULL) + u_freebranch(buf, uhp->uh_alt_next.ptr, uhpp); + + if (uhp->uh_alt_prev.ptr != NULL) + uhp->uh_alt_prev.ptr->uh_alt_next.ptr = NULL; + + /* Update the links in the list to remove the header. */ + if (uhp->uh_next.ptr == NULL) + buf->b_u_oldhead = uhp->uh_prev.ptr; + else + uhp->uh_next.ptr->uh_prev.ptr = uhp->uh_prev.ptr; + + if (uhp->uh_prev.ptr == NULL) + buf->b_u_newhead = uhp->uh_next.ptr; + else + for (uhap = uhp->uh_prev.ptr; uhap != NULL; + uhap = uhap->uh_alt_next.ptr) + uhap->uh_next.ptr = uhp->uh_next.ptr; + + u_freeentries(buf, uhp, uhpp); +} + +/* + * Free an alternate branch and any following alternate branches. + */ +static void +u_freebranch ( + buf_T *buf, + u_header_T *uhp, + u_header_T **uhpp /* if not NULL reset when freeing this header */ +) +{ + u_header_T *tofree, *next; + + /* If this is the top branch we may need to use u_freeheader() to update + * all the pointers. */ + if (uhp == buf->b_u_oldhead) { + while (buf->b_u_oldhead != NULL) + u_freeheader(buf, buf->b_u_oldhead, uhpp); + return; + } + + if (uhp->uh_alt_prev.ptr != NULL) + uhp->uh_alt_prev.ptr->uh_alt_next.ptr = NULL; + + next = uhp; + while (next != NULL) { + tofree = next; + if (tofree->uh_alt_next.ptr != NULL) + u_freebranch(buf, tofree->uh_alt_next.ptr, uhpp); /* recursive */ + next = tofree->uh_prev.ptr; + u_freeentries(buf, tofree, uhpp); + } +} + +/* + * Free all the undo entries for one header and the header itself. + * This means that "uhp" is invalid when returning. + */ +static void +u_freeentries ( + buf_T *buf, + u_header_T *uhp, + u_header_T **uhpp /* if not NULL reset when freeing this header */ +) +{ + u_entry_T *uep, *nuep; + + /* Check for pointers to the header that become invalid now. */ + if (buf->b_u_curhead == uhp) + buf->b_u_curhead = NULL; + if (buf->b_u_newhead == uhp) + buf->b_u_newhead = NULL; /* freeing the newest entry */ + if (uhpp != NULL && uhp == *uhpp) + *uhpp = NULL; + + for (uep = uhp->uh_entry; uep != NULL; uep = nuep) { + nuep = uep->ue_next; + u_freeentry(uep, uep->ue_size); + } + +#ifdef U_DEBUG + uhp->uh_magic = 0; +#endif + free((char_u *)uhp); + --buf->b_u_numhead; +} + +/* + * free entry 'uep' and 'n' lines in uep->ue_array[] + */ +static void u_freeentry(u_entry_T *uep, long n) +{ + while (n > 0) + free(uep->ue_array[--n]); + free((char_u *)uep->ue_array); +#ifdef U_DEBUG + uep->ue_magic = 0; +#endif + free((char_u *)uep); +} + +/* + * invalidate the undo buffer; called when storage has already been released + */ +void u_clearall(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(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(void) +{ + if (curbuf->b_u_line_ptr != NULL) { + free(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. + * Careful: may trigger autocommands that reload the buffer. + */ +void u_undoline(void) +{ + 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, FALSE) == 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); + free(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; + check_cursor_col(); +} + +/* + * Free all allocated memory blocks for the buffer 'buf'. + */ +void u_blockfree(buf_T *buf) +{ + while (buf->b_u_oldhead != NULL) + u_freeheader(buf, buf->b_u_oldhead, NULL); + free(buf->b_u_line_ptr); +} + +/* + * u_save_line(): allocate memory and copy line 'lnum' into it. + * Returns NULL when out of memory. + */ +static char_u *u_save_line(linenr_T lnum) +{ + return vim_strsave(ml_get(lnum)); +} + +/* + * 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_T *buf) +{ + return + !bt_dontwrite(buf) && + (buf->b_changed || file_ff_differs(buf, TRUE)); +} + +int curbufIsChanged(void) +{ + return + !bt_dontwrite(curbuf) && + (curbuf->b_changed || file_ff_differs(curbuf, TRUE)); +} + +/* + * For undotree(): Append the list of undo blocks at "first_uhp" to "list". + * Recursive. + */ +void u_eval_tree(u_header_T *first_uhp, list_T *list) +{ + u_header_T *uhp = first_uhp; + dict_T *dict; + + while (uhp != NULL) { + dict = dict_alloc(); + if (dict == NULL) + return; + dict_add_nr_str(dict, "seq", uhp->uh_seq, NULL); + dict_add_nr_str(dict, "time", (long)uhp->uh_time, NULL); + if (uhp == curbuf->b_u_newhead) + dict_add_nr_str(dict, "newhead", 1, NULL); + if (uhp == curbuf->b_u_curhead) + dict_add_nr_str(dict, "curhead", 1, NULL); + if (uhp->uh_save_nr > 0) + dict_add_nr_str(dict, "save", uhp->uh_save_nr, NULL); + + if (uhp->uh_alt_next.ptr != NULL) { + list_T *alt_list = list_alloc(); + + if (alt_list != NULL) { + /* Recursive call to add alternate undo tree. */ + u_eval_tree(uhp->uh_alt_next.ptr, alt_list); + dict_add_list(dict, "alt", alt_list); + } + } + + list_append_dict(list, dict); + uhp = uhp->uh_prev.ptr; + } +} |