2 * Copyright (c) 1992, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 * Copyright (c) 1992, 1993, 1994, 1995, 1996
5 * Keith Bostic. All rights reserved.
7 * See the LICENSE file for redistribution information.
12 #include <sys/types.h>
13 #include <sys/queue.h>
18 * We include <sys/file.h>, because the flock(2) and open(2) #defines
19 * were found there on historical systems. We also include <fcntl.h>
20 * because the open(2) #defines are found there on newer systems.
24 #include <bitstring.h>
36 static int file_backup(SCR *, char *, char *);
37 static void file_cinit(SCR *);
38 static void file_encinit(SCR *);
39 static void file_comment(SCR *);
40 static int file_spath(SCR *, FREF *, struct stat *, int *);
44 * Insert a file name into the FREF list, if it doesn't already
48 * The "if it doesn't already appear" changes vi's semantics slightly. If
49 * you do a "vi foo bar", and then execute "next bar baz", the edit of bar
50 * will reflect the line/column of the previous edit session. Historic nvi
51 * did not do this. The change is a logical extension of the change where
52 * vi now remembers the last location in any file that it has ever edited,
53 * not just the previously edited file.
55 * PUBLIC: FREF *file_add(SCR *, char *);
58 file_add(SCR *sp, char *name)
64 * Return it if it already exists. Note that we test against the
65 * user's name, whatever that happens to be, including if it's a
68 * If the user added a file but was unable to initialize it, there
69 * can be file list entries where the name field is NULL. Discard
70 * them the next time we see them.
74 TAILQ_FOREACH_SAFE(frp, gp->frefq, q, tfrp) {
75 if (frp->name == NULL) {
76 TAILQ_REMOVE(gp->frefq, frp, q);
81 if (!strcmp(frp->name, name))
85 /* Allocate and initialize the FREF structure. */
86 CALLOC(sp, frp, 1, sizeof(FREF));
91 * If no file name specified, or if the file name is a request
92 * for something temporary, file_init() will allocate the file
93 * name. Temporary files are always ignored.
95 if (name != NULL && strcmp(name, TEMPORARY_FILE_STRING) &&
96 (frp->name = strdup(name)) == NULL) {
98 msgq(sp, M_SYSERR, NULL);
102 /* Append into the chain of file names. */
103 TAILQ_INSERT_TAIL(gp->frefq, frp, q);
110 * Start editing a file, based on the FREF structure. If successsful,
111 * let go of any previous file. Don't release the previous file until
112 * absolutely sure we have the new one.
114 * PUBLIC: int file_init(SCR *, FREF *, char *, int);
117 file_init(SCR *sp, FREF *frp, char *rcv_name, int flags)
120 RECNOINFO oinfo = { 0 };
123 int fd, exists, open_err, readonly;
126 open_err = readonly = 0;
129 * If the file is a recovery file, let the recovery code handle it.
130 * Clear the FR_RECOVER flag first -- the recovery code does set up,
131 * and then calls us! If the recovery call fails, it's probably
132 * because the named file doesn't exist. So, move boldly forward,
133 * presuming that there's an error message the user will get to see.
135 if (F_ISSET(frp, FR_RECOVER)) {
136 F_CLR(frp, FR_RECOVER);
137 return (rcv_read(sp, frp));
141 * Required FRP initialization; the only flag we keep is the
142 * cursor information.
144 F_CLR(frp, ~FR_CURSORSET);
147 * Required EXF initialization:
148 * Flush the line caches.
149 * Default recover mail file fd to -1.
150 * Set initial EXF flag bits.
152 CALLOC_RET(sp, ep, 1, sizeof(EXF));
153 ep->c_lno = ep->c_nlines = OOBLNO;
155 F_SET(ep, F_FIRSTMODIFY);
158 * Scan the user's path to find the file that we're going to
161 if (file_spath(sp, frp, &sb, &exists))
165 * If no name or backing file, for whatever reason, create a backing
166 * temporary file, saving the temp file name so we can later unlink
167 * it. If the user never named this file, copy the temporary file name
168 * to the real name (we display that until the user renames it).
171 if (LF_ISSET(FS_OPENERR) || oname == NULL || !exists) {
174 if (opts_empty(sp, O_TMPDIR, 0))
177 join(O_STR(sp, O_TMPDIR), "vi.XXXXXXXXXX")) == NULL) {
178 msgq(sp, M_SYSERR, NULL);
181 if ((fd = mkstemp(tname)) == -1 || fstat(fd, &sb)) {
184 "237|Unable to create temporary file");
190 if (frp->name == NULL) {
191 F_SET(frp, FR_TMPFILE);
192 if ((frp->name = strdup(tname)) == NULL) {
193 msgq(sp, M_SYSERR, NULL);
199 if (!LF_ISSET(FS_OPENERR))
200 F_SET(frp, FR_NEWFILE);
202 ep->mtim = sb.st_mtim;
206 * A seat of the pants calculation: try to keep the file in
207 * 15 pages or less. Don't use a page size larger than 16K
208 * (vi should have good locality) or smaller than 1K.
210 psize = ((sb.st_size / 15) + 1023) / 1024;
215 psize = p2roundup(psize) << 10;
218 ep->mdev = sb.st_dev;
219 ep->minode = sb.st_ino;
221 ep->mtim = sb.st_mtim;
223 if (!S_ISREG(sb.st_mode))
224 msgq_str(sp, M_ERR, oname,
225 "238|Warning: %s is not a regular file");
228 /* Set up recovery. */
229 oinfo.bval = '\n'; /* Always set. */
231 oinfo.flags = F_ISSET(sp->gp, G_SNAPSHOT) ? R_SNAPSHOT : 0;
232 if (rcv_name == NULL) {
233 if (!rcv_tmp(sp, ep, frp->name))
234 oinfo.bfname = ep->rcv_path;
236 if ((ep->rcv_path = strdup(rcv_name)) == NULL) {
237 msgq(sp, M_SYSERR, NULL);
240 oinfo.bfname = ep->rcv_path;
241 F_SET(ep, F_MODIFIED);
244 /* Open a db structure. */
245 if ((ep->db = dbopen(rcv_name == NULL ? oname : NULL,
246 O_NONBLOCK | O_RDONLY,
247 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH,
248 DB_RECNO, &oinfo)) == NULL) {
250 M_SYSERR, rcv_name == NULL ? oname : rcv_name, "%s");
251 if (F_ISSET(frp, FR_NEWFILE))
255 * Historically, vi permitted users to edit files that couldn't
256 * be read. This isn't useful for single files from a command
257 * line, but it's quite useful for "vi *.c", since you can skip
258 * past files that you can't read.
265 * Do the remaining things that can cause failure of the new file,
266 * mark and logging initialization.
268 if (mark_init(sp, ep) || log_init(sp, ep))
272 * Set the alternate file name to be the file we're discarding.
275 * Temporary files can't become alternate files, so there's no file
276 * name. This matches historical practice, although it could only
277 * happen in historical vi as the result of the initial command, i.e.
278 * if vi was executed without a file name.
280 if (LF_ISSET(FS_SETALT))
281 set_alt_name(sp, sp->frp == NULL ||
282 F_ISSET(sp->frp, FR_TMPFILE) ? NULL : sp->frp->name);
285 * Close the previous file; if that fails, close the new one and run
289 * There's a nasty special case. If the user edits a temporary file,
290 * and then does an ":e! %", we need to re-initialize the backing
291 * file, but we can't change the name. (It's worse -- we're dealing
292 * with *names* here, we can't even detect that it happened.) Set a
293 * flag so that the file_end routine ignores the backing information
294 * of the old file if it happens to be the same as the new one.
297 * Side-effect: after the call to file_end(), sp->frp may be NULL.
299 if (sp->ep != NULL) {
300 F_SET(frp, FR_DONTDELETE);
301 if (file_end(sp, NULL, LF_ISSET(FS_FORCE))) {
302 (void)file_end(sp, ep, 1);
305 F_CLR(frp, FR_DONTDELETE);
309 * Lock the file; if it's a recovery file, it should already be
310 * locked. Note, we acquire the lock after the previous file
311 * has been ended, so that we don't get an "already locked" error
315 * While the user can't interrupt us between the open and here,
316 * there's a race between the dbopen() and the lock. Not much
317 * we can do about it.
320 * We don't make a big deal of not being able to lock the file. As
321 * locking rarely works over NFS, and often fails if the file was
322 * mmap(2)'d, it's far too common to do anything like print an error
323 * message, let alone make the file readonly. At some future time,
324 * when locking is a little more reliable, this should change to be
327 if (rcv_name == NULL)
328 switch (file_lock(sp, oname, ep->db->fd(ep->db), 0)) {
330 F_SET(frp, FR_UNLOCKED);
334 if (F_ISSET(sp, SC_READONLY))
336 msgq_str(sp, M_INFO, oname,
337 "239|%s already locked, session is read-only");
344 * Historically, the readonly edit option was set per edit buffer in
345 * vi, unless the -R command-line option was specified or the program
346 * was executed as "view". (Well, to be truthful, if the letter 'w'
347 * occurred anywhere in the program name, but let's not get into that.)
348 * So, the persistent readonly state has to be stored in the screen
349 * structure, and the edit option value toggles with the contents of
350 * the edit buffer. If the persistent readonly flag is set, set the
351 * readonly edit option.
353 * Otherwise, try and figure out if a file is readonly. This is a
354 * dangerous thing to do. The kernel is the only arbiter of whether
355 * or not a file is writeable, and the best that a user program can
356 * do is guess. Obvious loopholes are files that are on a file system
357 * mounted readonly (access catches this one on a few systems), or
358 * alternate protection mechanisms, ACL's for example, that we can't
359 * portably check. Lots of fun, and only here because users whined.
362 * Historic vi displayed the readonly message if none of the file
363 * write bits were set, or if an an access(2) call on the path
364 * failed. This seems reasonable. If the file is mode 444, root
365 * users may want to know that the owner of the file did not expect
368 * Historic vi set the readonly bit if no write bits were set for
369 * a file, even if the access call would have succeeded. This makes
370 * the superuser force the write even when vi expects that it will
371 * succeed. I'm less supportive of this semantic, but it's historic
372 * practice and the conservative approach to vi'ing files as root.
374 * It would be nice if there was some way to update this when the user
375 * does a "^Z; chmod ...". The problem is that we'd first have to
376 * distinguish between readonly bits set because of file permissions
377 * and those set for other reasons. That's not too hard, but deciding
378 * when to reevaluate the permissions is trickier. An alternative
379 * might be to turn off the readonly bit if the user forces a write
383 * Access(2) doesn't consider the effective uid/gid values. This
384 * probably isn't a problem for vi when it's running standalone.
386 if (readonly || F_ISSET(sp, SC_READONLY) ||
387 (!F_ISSET(frp, FR_NEWFILE) &&
388 (!(sb.st_mode & (S_IWUSR | S_IWGRP | S_IWOTH)) ||
389 access(frp->name, W_OK))))
390 O_SET(sp, O_READONLY);
392 O_CLR(sp, O_READONLY);
399 /* Detect and set the file encoding */
402 /* Set the initial cursor position, queue initial command. */
405 /* Redraw the screen from scratch, schedule a welcome message. */
406 F_SET(sp, SC_SCR_REFORMAT | SC_STATUS);
410 err: free(frp->name);
412 if (frp->tname != NULL) {
413 (void)unlink(frp->tname);
418 oerr: if (F_ISSET(ep, F_RCV_ON))
419 (void)unlink(ep->rcv_path);
424 (void)ep->db->close(ep->db);
428 file_init(sp, frp, rcv_name, flags | FS_OPENERR) : 1);
433 * Scan the user's path to find the file that we're going to
437 file_spath(SCR *sp, FREF *frp, struct stat *sbp, int *existsp)
442 char *name, *p, *t, *path;
445 * If the name is NULL or an explicit reference (i.e., the first
446 * component is . or ..) ignore the O_PATH option.
453 if (name[0] == '/' || (name[0] == '.' &&
454 (name[1] == '/' || (name[1] == '.' && name[2] == '/')))) {
455 *existsp = !stat(name, sbp);
460 if (!stat(name, sbp)) {
465 /* Try the O_PATH option values. */
466 for (found = 0, p = t = O_STR(sp, O_PATH);; ++p)
467 if (*p == ':' || *p == '\0') {
469 * Ignore the empty strings and ".", since we've already
470 * tried the current directory.
472 if (t < p && (p - t != 1 || *t != '.')) {
475 if ((path = join(t, name)) == NULL) {
476 msgq(sp, M_SYSERR, NULL);
481 if (!stat(path, sbp)) {
492 /* If we found it, build a new pathname and discard the old one. */
503 * Set up the initial cursor position.
515 /* Set some basic defaults. */
520 * Historically, initial commands (the -c option) weren't executed
521 * until a file was loaded, e.g. "vi +10 nofile", followed by an
522 * :edit or :tag command, would execute the +10 on the file loaded
523 * by the subsequent command, (assuming that it existed). This
524 * applied as well to files loaded using the tag commands, and we
525 * follow that historic practice. Also, all initial commands were
526 * ex commands and were always executed on the last line of the file.
528 * Otherwise, if no initial command for this file:
529 * If in ex mode, move to the last line, first nonblank character.
530 * If the file has previously been edited, move to the last known
531 * position, and check it for validity.
532 * Otherwise, move to the first line, first nonblank.
534 * This gets called by the file init code, because we may be in a
535 * file of ex commands and we want to execute them from the right
536 * location in the file.
540 if (gp->c_option != NULL && !F_ISSET(sp->frp, FR_NEWFILE)) {
541 if (db_last(sp, &sp->lno))
547 CHAR2INT(sp, gp->c_option, strlen(gp->c_option) + 1,
549 if (ex_run_str(sp, "-c option", wp, wlen - 1, 1, 0))
552 } else if (F_ISSET(sp, SC_EX)) {
553 if (db_last(sp, &sp->lno))
562 if (F_ISSET(sp->frp, FR_CURSORSET)) {
563 sp->lno = sp->frp->lno;
564 sp->cno = sp->frp->cno;
566 /* If returning to a file in vi, center the line. */
567 F_SET(sp, SC_SCR_CENTER);
569 if (O_ISSET(sp, O_COMMENT))
575 if (db_get(sp, sp->lno, 0, NULL, &len)) {
580 if (!nb && sp->cno > len)
585 (void)nonblank(sp, sp->lno, &sp->cno);
590 * The initial column is also the most attractive column.
596 * Historically, vi initialized the absolute mark, but ex did not.
597 * Which meant, that if the first command in ex mode was "visual",
598 * or if an ex command was executed first (e.g. vi +10 file) vi was
599 * entered without the mark being initialized. For consistency, if
600 * the file isn't empty, we initialize it for everyone, believing
601 * that it can't hurt, and is generally useful. Not initializing it
602 * if the file is empty is historic practice, although it has always
603 * been possible to set (and use) marks in empty vi files.
607 (void)mark_set(sp, ABSMARK1, &m, 0);
612 * Stop editing a file.
614 * PUBLIC: int file_end(SCR *, EXF *, int);
617 file_end(SCR *sp, EXF *ep, int force)
623 * ep MAY NOT BE THE SAME AS sp->ep, DON'T USE THE LATTER.
624 * (If argument ep is NULL, use sp->ep.)
626 * If multiply referenced, just decrement the count and return.
630 if (--ep->refcnt != 0)
635 * Clean up the FREF structure.
637 * Save the cursor location.
640 * It would be cleaner to do this somewhere else, but by the time
641 * ex or vi knows that we're changing files it's already happened.
646 F_SET(frp, FR_CURSORSET);
649 * We may no longer need the temporary backing file, so clean it
650 * up. We don't need the FREF structure either, if the file was
651 * never named, so lose it.
654 * Re: FR_DONTDELETE, see the comment above in file_init().
656 if (!F_ISSET(frp, FR_DONTDELETE) && frp->tname != NULL) {
657 if (unlink(frp->tname))
658 msgq_str(sp, M_SYSERR, frp->tname, "240|%s: remove");
661 if (F_ISSET(frp, FR_TMPFILE)) {
662 TAILQ_REMOVE(sp->gp->frefq, frp, q);
670 * Clean up the EXF structure.
672 * Close the db structure.
674 if (ep->db->close != NULL && ep->db->close(ep->db) && !force) {
675 msgq_str(sp, M_SYSERR, frp->name, "241|%s: close");
680 /* COMMITTED TO THE CLOSE. THERE'S NO GOING BACK... */
683 (void)log_end(sp, ep);
685 /* Free up any marks. */
686 (void)mark_end(sp, ep);
689 * Delete recovery files, close the open descriptor, free recovery
690 * memory. See recover.c for a description of the protocol.
693 * Unlink backup file first, we can detect that the recovery file
694 * doesn't reference anything when the user tries to recover it.
695 * There's a race, here, obviously, but it's fairly small.
697 if (!F_ISSET(ep, F_RCV_NORM)) {
698 if (ep->rcv_path != NULL && unlink(ep->rcv_path))
699 msgq_str(sp, M_SYSERR, ep->rcv_path, "242|%s: remove");
700 if (ep->rcv_mpath != NULL && unlink(ep->rcv_mpath))
701 msgq_str(sp, M_SYSERR, ep->rcv_mpath, "243|%s: remove");
703 if (ep->rcv_fd != -1)
704 (void)close(ep->rcv_fd);
716 * Write the file to disk. Historic vi had fairly convoluted
717 * semantics for whether or not writes would happen. That's
720 * PUBLIC: int file_write(SCR *, MARK *, MARK *, char *, int);
723 file_write(SCR *sp, MARK *fm, MARK *tm, char *name, int flags)
725 enum { NEWFILE, OLDFILE } mtype;
733 int fd, nf, noname, oflags, rval;
734 char *p, *s, *t, buf[1024];
741 * Writing '%', or naming the current file explicitly, has the
742 * same semantics as writing without a name.
744 if (name == NULL || !strcmp(name, frp->name)) {
750 /* Can't write files marked read-only, unless forced. */
751 if (!LF_ISSET(FS_FORCE) && noname && O_ISSET(sp, O_READONLY)) {
752 msgq(sp, M_ERR, LF_ISSET(FS_POSSIBLE) ?
753 "244|Read-only file, not written; use ! to override" :
754 "245|Read-only file, not written");
758 /* If not forced, not appending, and "writeany" not set ... */
759 if (!LF_ISSET(FS_FORCE | FS_APPEND) && !O_ISSET(sp, O_WRITEANY)) {
760 /* Don't overwrite anything but the original file. */
761 if ((!noname || F_ISSET(frp, FR_NAMECHANGE)) &&
763 msgq_str(sp, M_ERR, name,
764 LF_ISSET(FS_POSSIBLE) ?
765 "246|%s exists, not written; use ! to override" :
766 "247|%s exists, not written");
771 * Don't write part of any existing file. Only test for the
772 * original file, the previous test catches anything else.
774 if (!LF_ISSET(FS_ALL) && noname && !stat(name, &sb)) {
775 msgq(sp, M_ERR, LF_ISSET(FS_POSSIBLE) ?
776 "248|Partial file, not written; use ! to override" :
777 "249|Partial file, not written");
783 * Figure out if the file already exists -- if it doesn't, we display
784 * the "new file" message. The stat might not be necessary, but we
785 * just repeat it because it's easier than hacking the previous tests.
786 * The information is only used for the user message and modification
787 * time test, so we can ignore the obvious race condition.
789 * One final test. If we're not forcing or appending the current file,
790 * and we have a saved modification time, object if the file changed
791 * since we last edited or wrote it, and make them force it.
796 if (noname && !LF_ISSET(FS_FORCE | FS_APPEND) &&
797 ((F_ISSET(ep, F_DEVSET) &&
798 (sb.st_dev != ep->mdev || sb.st_ino != ep->minode)) ||
799 timespeccmp(&sb.st_mtim, &ep->mtim, !=))) {
800 msgq_str(sp, M_ERR, name, LF_ISSET(FS_POSSIBLE) ?
801 "250|%s: file modified more recently than this copy; use ! to override" :
802 "251|%s: file modified more recently than this copy");
809 /* Set flags to create, write, and either append or truncate. */
810 oflags = O_CREAT | O_WRONLY |
811 (LF_ISSET(FS_APPEND) ? O_APPEND : O_TRUNC);
813 /* Backup the file if requested. */
814 if (!opts_empty(sp, O_BACKUP, 1) &&
815 file_backup(sp, name, O_STR(sp, O_BACKUP)) && !LF_ISSET(FS_FORCE))
819 if ((fd = open(name, oflags,
820 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)) < 0) {
821 if (errno == EACCES && LF_ISSET(FS_FORCE)) {
823 * If the user owns the file but does not
824 * have write permission on it, grant it
825 * automatically for the duration of the
826 * opening of the file, if possible.
831 if (stat(name, &sb) != 0)
834 if (!(sb.st_mode & S_IWUSR) && sb.st_uid == getuid())
838 if (chmod(name, fmode) != 0)
840 fd = open(name, oflags, S_IRUSR | S_IWUSR |
841 S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
844 (void)fchmod(fd, sb.st_mode);
849 msgq_str(sp, M_SYSERR, name, "%s");
854 /* Try and get a lock. */
855 if (!noname && file_lock(sp, NULL, fd, 0) == LOCK_UNAVAIL)
856 msgq_str(sp, M_ERR, name,
857 "252|%s: write lock was unavailable");
860 * Use stdio for buffering.
863 * SVR4.2 requires the fdopen mode exactly match the original open
864 * mode, i.e. you have to open with "a" if appending.
866 if ((fp = fdopen(fd, LF_ISSET(FS_APPEND) ? "a" : "w")) == NULL) {
867 msgq_str(sp, M_SYSERR, name, "%s");
872 /* Build fake addresses, if necessary. */
877 if (db_last(sp, &to.lno))
883 rval = ex_writefp(sp, name, fp, fm, tm, &nlno, &nch, 0);
886 * Save the new last modification time -- even if the write fails
887 * we re-init the time. That way the user can clean up the disk
888 * and rewrite without having to force it.
892 timepoint_system(&ep->mtim);
895 ep->mdev = sb.st_dev;
896 ep->minode = sb.st_ino;
898 ep->mtim = sb.st_mtim;
903 * If the write failed, complain loudly. ex_writefp() has already
904 * complained about the actual error, reinforce it if data was lost.
907 if (!LF_ISSET(FS_APPEND))
908 msgq_str(sp, M_ERR, name,
909 "254|%s: WARNING: FILE TRUNCATED");
914 * Once we've actually written the file, it doesn't matter that the
915 * file name was changed -- if it was, we've already whacked it.
917 F_CLR(frp, FR_NAMECHANGE);
920 * If wrote the entire file, and it wasn't by appending it to a file,
921 * clear the modified bit. If the file was written to the original
922 * file name and the file is a temporary, set the "no exit" bit. This
923 * permits the user to write the file and use it in the context of the
924 * filesystem, but still keeps them from discarding their changes by
927 if (LF_ISSET(FS_ALL) && !LF_ISSET(FS_APPEND)) {
928 F_CLR(ep, F_MODIFIED);
929 if (F_ISSET(frp, FR_TMPFILE)) {
931 F_SET(frp, FR_TMPEXIT);
933 F_CLR(frp, FR_TMPEXIT);
937 p = msg_print(sp, name, &nf);
941 "256|%s: new file: %lu lines, %lu characters", NULL);
942 len = snprintf(buf, sizeof(buf), msgstr, p, nlno, nch);
945 msgstr = msg_cat(sp, LF_ISSET(FS_APPEND) ?
946 "315|%s: appended: %lu lines, %lu characters" :
947 "257|%s: %lu lines, %lu characters", NULL);
948 len = snprintf(buf, sizeof(buf), msgstr, p, nlno, nch);
955 * There's a nasty problem with long path names. Cscope and tags files
956 * can result in long paths and vi will request a continuation key from
957 * the user. Unfortunately, the user has typed ahead, and chaos will
958 * result. If we assume that the characters in the filenames only take
959 * a single screen column each, we can trim the filename.
962 if (len >= sp->cols) {
963 for (s = buf, t = buf + strlen(p); s < t &&
964 (*s != '/' || len >= sp->cols - 3); ++s, --len);
968 *--s = '.'; /* Leading ellipses. */
973 msgq(sp, M_INFO, "%s", s);
975 FREE_SPACE(sp, p, 0);
981 * Backup the about-to-be-written file.
984 * We do the backup by copying the entire file. It would be nice to do
985 * a rename instead, but: (1) both files may not fit and we want to fail
986 * before doing the rename; (2) the backup file may not be on the same
987 * disk partition as the file being written; (3) there may be optional
988 * file information (MACs, DACs, whatever) that we won't get right if we
989 * recreate the file. So, let's not risk it.
992 file_backup(SCR *sp, char *name, char *bname)
1000 int flags, maxnum, nr, num, nw, rfd, wfd, version;
1001 char *bp, *estr, *p, *pct, *slash, *t, *wfname, buf[8192];
1008 bp = estr = wfname = NULL;
1011 * Open the current file for reading. Do this first, so that
1012 * we don't exec a shell before the most likely failure point.
1013 * If it doesn't exist, it's okay, there's just nothing to back
1017 if ((rfd = open(name, O_RDONLY, 0)) < 0) {
1018 if (errno == ENOENT)
1025 * If the name starts with an 'N' character, add a version number
1026 * to the name. Strip the leading N from the string passed to the
1027 * expansion routines, for no particular reason. It would be nice
1028 * to permit users to put the version number anywhere in the backup
1029 * name, but there isn't a special character that we can use in the
1030 * name, and giving a new character a special meaning leads to ugly
1031 * hacks both here and in the supporting ex routines.
1033 * Shell and file name expand the option's value.
1035 ex_cinit(sp, &cmd, 0, 0, 0, 0, 0);
1036 if (bname[0] == 'N') {
1041 CHAR2INT(sp, bname, strlen(bname), wp, wlen);
1042 if ((wp = v_wstrdup(sp, wp, wlen)) == NULL)
1044 if (argv_exp2(sp, &cmd, wp, wlen)) {
1051 * 0 args: impossible.
1053 * >1 args: object, too many args.
1055 if (cmd.argc != 1) {
1056 msgq_str(sp, M_ERR, bname,
1057 "258|%s expanded into too many file names");
1063 * If appending a version number, read through the directory, looking
1064 * for file names that match the name followed by a number. Make all
1065 * of the other % characters in name literal, so the user doesn't get
1066 * surprised and sscanf doesn't drop core indirecting through pointers
1067 * that don't exist. If any such files are found, increment its number
1071 GET_SPACE_GOTOC(sp, bp, blen, cmd.argv[0]->len * 2 + 50);
1072 INT2CHAR(sp, cmd.argv[0]->bp, cmd.argv[0]->len + 1,
1076 for (t = bp, slash = NULL;
1077 p[0] != '\0'; *t++ = *p++)
1081 } else if (p[0] == '/')
1088 if (slash == NULL) {
1089 dirp = opendir(".");
1098 INT2CHAR(sp, cmd.argv[0]->bp, cmd.argv[0]->len + 1,
1103 for (maxnum = 0; (dp = readdir(dirp)) != NULL;)
1104 if (sscanf(dp->d_name, p, &num) == 1 && num > maxnum)
1106 (void)closedir(dirp);
1108 /* Format the backup file name. */
1109 (void)snprintf(pct, blen - (pct - bp), "%d", maxnum + 1);
1113 INT2CHAR(sp, cmd.argv[0]->bp, cmd.argv[0]->len + 1,
1117 /* Open the backup file, avoiding lurkers. */
1118 if (stat(wfname, &sb) == 0) {
1119 if (!S_ISREG(sb.st_mode)) {
1120 msgq_str(sp, M_ERR, bname,
1121 "259|%s: not a regular file");
1124 if (sb.st_uid != getuid()) {
1125 msgq_str(sp, M_ERR, bname, "260|%s: not owned by you");
1128 if (sb.st_mode & (S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)) {
1129 msgq_str(sp, M_ERR, bname,
1130 "261|%s: accessible by a user other than the owner");
1135 flags = O_CREAT | O_EXCL;
1136 if ((wfd = open(wfname, flags | O_WRONLY, S_IRUSR | S_IWUSR)) < 0) {
1141 /* Copy the file's current contents to its backup value. */
1142 while ((nr = read(rfd, buf, sizeof(buf))) > 0)
1143 for (off = 0; nr != 0; nr -= nw, off += nw)
1144 if ((nw = write(wfd, buf + off, nr)) < 0) {
1163 FREE_SPACE(sp, bp, blen);
1170 (void)unlink(wfname);
1174 msgq_str(sp, M_SYSERR, estr, "%s");
1177 FREE_SPACE(sp, bp, blen);
1183 * Read the first line and set the O_FILEENCODING.
1186 file_encinit(SCR *sp)
1188 #if defined(USE_WIDECHAR) && defined(USE_ICONV)
1192 char buf[4096]; /* not need to be '\0'-terminated */
1198 while (!db_rget(sp, ln++, &p, &len)) {
1199 if (blen + len > sizeof(buf))
1200 len = sizeof(buf) - blen;
1201 memcpy(buf + blen, p, len);
1203 if (blen == sizeof(buf))
1210 * Detect UTF-8 and fallback to the locale/preset encoding.
1213 * A manually set O_FILEENCODING indicates the "fallback
1214 * encoding", but UTF-8, which can be safely detected, is not
1215 * inherited from the old screen.
1217 if (looks_utf8(buf, blen) > 1)
1218 o_set(sp, O_FILEENCODING, OS_STRDUP, "utf-8", 0);
1219 else if (!O_ISSET(sp, O_FILEENCODING) ||
1220 !strcasecmp(O_STR(sp, O_FILEENCODING), "utf-8"))
1221 o_set(sp, O_FILEENCODING, OS_STRDUP, codeset(), 0);
1223 conv_enc(sp, O_FILEENCODING, 0);
1229 * Skip the first comment.
1232 file_comment(SCR *sp)
1238 for (lno = 1; !db_get(sp, lno, 0, &p, &len) && len == 0; ++lno);
1242 F_SET(sp, SC_SCR_TOP);
1243 while (!db_get(sp, ++lno, 0, &p, &len))
1244 if (len < 1 || p[0] != '#') {
1248 } else if (len > 1 && p[0] == '/' && p[1] == '*') {
1249 F_SET(sp, SC_SCR_TOP);
1251 for (; len > 1; --len, ++p)
1252 if (p[0] == '*' && p[1] == '/') {
1256 } while (!db_get(sp, ++lno, 0, &p, &len));
1257 } else if (len > 1 && p[0] == '/' && p[1] == '/') {
1258 F_SET(sp, SC_SCR_TOP);
1262 for (; len > 1; --len, ++p)
1263 if (p[0] == '/' && p[1] == '/') {
1267 } while (!db_get(sp, ++lno, 0, &p, &len));
1273 * First modification check routine. The :next, :prev, :rewind, :tag,
1274 * :tagpush, :tagpop, ^^ modifications check.
1276 * PUBLIC: int file_m1(SCR *, int, int);
1279 file_m1(SCR *sp, int force, int flags)
1285 /* If no file loaded, return no modifications. */
1290 * If the file has been modified, we'll want to write it back or
1291 * fail. If autowrite is set, we'll write it back automatically,
1292 * unless force is also set. Otherwise, we fail unless forced or
1293 * there's another open screen on this file.
1295 if (F_ISSET(ep, F_MODIFIED)) {
1296 if (O_ISSET(sp, O_AUTOWRITE)) {
1297 if (!force && file_aw(sp, flags))
1299 } else if (ep->refcnt <= 1 && !force) {
1300 msgq(sp, M_ERR, LF_ISSET(FS_POSSIBLE) ?
1301 "262|File modified since last complete write; write or use ! to override" :
1302 "263|File modified since last complete write; write or use :edit! to override");
1307 return (file_m3(sp, force));
1312 * Second modification check routine. The :edit, :quit, :recover
1313 * modifications check.
1315 * PUBLIC: int file_m2(SCR *, int);
1318 file_m2(SCR *sp, int force)
1324 /* If no file loaded, return no modifications. */
1329 * If the file has been modified, we'll want to fail, unless forced
1330 * or there's another open screen on this file.
1332 if (F_ISSET(ep, F_MODIFIED) && ep->refcnt <= 1 && !force) {
1334 "264|File modified since last complete write; write or use ! to override");
1338 return (file_m3(sp, force));
1343 * Third modification check routine.
1345 * PUBLIC: int file_m3(SCR *, int);
1348 file_m3(SCR *sp, int force)
1354 /* If no file loaded, return no modifications. */
1359 * Don't exit while in a temporary files if the file was ever modified.
1360 * The problem is that if the user does a ":wq", we write and quit,
1361 * unlinking the temporary file. Not what the user had in mind at all.
1362 * We permit writing to temporary files, so that user maps using file
1363 * system names work with temporary files.
1365 if (F_ISSET(sp->frp, FR_TMPEXIT) && ep->refcnt <= 1 && !force) {
1367 "265|File is a temporary; exit will discard modifications");
1375 * Autowrite routine. If modified, autowrite is set and the readonly bit
1376 * is not set, write the file. A routine so there's a place to put the
1379 * PUBLIC: int file_aw(SCR *, int);
1382 file_aw(SCR *sp, int flags)
1384 if (!F_ISSET(sp->ep, F_MODIFIED))
1386 if (!O_ISSET(sp, O_AUTOWRITE))
1391 * Historic 4BSD vi attempted to write the file if autowrite was set,
1392 * regardless of the writeability of the file (as defined by the file
1393 * readonly flag). System V changed this as some point, not attempting
1394 * autowrite if the file was readonly. This feels like a bug fix to
1395 * me (e.g. the principle of least surprise is violated if readonly is
1396 * set and vi writes the file), so I'm compatible with System V.
1398 if (O_ISSET(sp, O_READONLY)) {
1400 "266|File readonly, modifications not auto-written");
1403 return (file_write(sp, NULL, NULL, NULL, flags));
1408 * Set the alternate pathname.
1410 * Set the alternate pathname. It's a routine because I wanted some place
1411 * to hang this comment. The alternate pathname (normally referenced using
1412 * the special character '#' during file expansion and in the vi ^^ command)
1413 * is set by almost all ex commands that take file names as arguments. The
1414 * rules go something like this:
1416 * 1: If any ex command takes a file name as an argument (except for the
1417 * :next command), the alternate pathname is set to that file name.
1418 * This excludes the command ":e" and ":w !command" as no file name
1419 * was specified. Note, historically, the :source command did not set
1420 * the alternate pathname. It does in nvi, for consistency.
1422 * 2: However, if any ex command sets the current pathname, e.g. the
1423 * ":e file" or ":rew" commands succeed, then the alternate pathname
1424 * is set to the previous file's current pathname, if it had one.
1425 * This includes the ":file" command and excludes the ":e" command.
1426 * So, by rule #1 and rule #2, if ":edit foo" fails, the alternate
1427 * pathname will be "foo", if it succeeds, the alternate pathname will
1428 * be the previous current pathname. The ":e" command will not set
1429 * the alternate or current pathnames regardless.
1431 * 3: However, if it's a read or write command with a file argument and
1432 * the current pathname has not yet been set, the file name becomes
1433 * the current pathname, and the alternate pathname is unchanged.
1435 * If the user edits a temporary file, there may be times when there is no
1436 * alternative file name. A name argument of NULL turns it off.
1438 * PUBLIC: void set_alt_name(SCR *, char *);
1441 set_alt_name(SCR *sp, char *name)
1445 sp->alt_name = NULL;
1446 else if ((sp->alt_name = strdup(name)) == NULL)
1447 msgq(sp, M_SYSERR, NULL);
1452 * Get an exclusive lock on a file.
1454 * PUBLIC: lockr_t file_lock(SCR *, char *, int, int);
1457 file_lock(SCR *sp, char *name, int fd, int iswrite)
1459 if (!O_ISSET(sp, O_LOCKFILES))
1460 return (LOCK_SUCCESS);
1464 * We need to distinguish a lock not being available for the file
1465 * from the file system not supporting locking. Flock is documented
1466 * as returning EWOULDBLOCK; add EAGAIN for good measure, and assume
1467 * they are the former. There's no portable way to do this.
1470 if (!flock(fd, LOCK_EX | LOCK_NB)) {
1471 fcntl(fd, F_SETFD, 1);
1472 return (LOCK_SUCCESS);
1474 return (errno == EAGAIN
1476 || errno == EWOULDBLOCK
1478 ? LOCK_UNAVAIL : LOCK_FAILED);