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.
9 * @(#)exf.c 10.49 (Berkeley) 10/10/96
10 * $FreeBSD: src/contrib/nvi/common/exf.c,v 1.3.2.2 2002/10/16 17:01:04 ru Exp $
11 * $DragonFly: src/contrib/nvi/common/exf.c,v 1.2 2003/06/17 04:24:04 dillon Exp $
16 #include <sys/param.h>
17 #include <sys/types.h> /* XXX: param.h may not have included types.h */
18 #include <sys/queue.h>
22 * We include <sys/file.h>, because the flock(2) and open(2) #defines
23 * were found there on historical systems. We also include <fcntl.h>
24 * because the open(2) #defines are found there on newer systems.
28 #include <bitstring.h>
40 static int file_backup __P((SCR *, char *, char *));
41 static void file_cinit __P((SCR *));
42 static void file_comment __P((SCR *));
43 static int file_spath __P((SCR *, FREF *, struct stat *, int *));
47 * Insert a file name into the FREF list, if it doesn't already
51 * The "if it doesn't already appear" changes vi's semantics slightly. If
52 * you do a "vi foo bar", and then execute "next bar baz", the edit of bar
53 * will reflect the line/column of the previous edit session. Historic nvi
54 * did not do this. The change is a logical extension of the change where
55 * vi now remembers the last location in any file that it has ever edited,
56 * not just the previously edited file.
58 * PUBLIC: FREF *file_add __P((SCR *, CHAR_T *));
69 * Return it if it already exists. Note that we test against the
70 * user's name, whatever that happens to be, including if it's a
73 * If the user added a file but was unable to initialize it, there
74 * can be file list entries where the name field is NULL. Discard
75 * them the next time we see them.
79 for (frp = gp->frefq.cqh_first;
80 frp != (FREF *)&gp->frefq; frp = frp->q.cqe_next) {
81 if (frp->name == NULL) {
82 tfrp = frp->q.cqe_next;
83 CIRCLEQ_REMOVE(&gp->frefq, frp, q);
84 if (frp->name != NULL)
90 if (!strcmp(frp->name, name))
94 /* Allocate and initialize the FREF structure. */
95 CALLOC(sp, frp, FREF *, 1, sizeof(FREF));
100 * If no file name specified, or if the file name is a request
101 * for something temporary, file_init() will allocate the file
102 * name. Temporary files are always ignored.
104 if (name != NULL && strcmp(name, TEMPORARY_FILE_STRING) &&
105 (frp->name = strdup(name)) == NULL) {
107 msgq(sp, M_SYSERR, NULL);
111 /* Append into the chain of file names. */
112 CIRCLEQ_INSERT_TAIL(&gp->frefq, frp, q);
119 * Start editing a file, based on the FREF structure. If successsful,
120 * let go of any previous file. Don't release the previous file until
121 * absolutely sure we have the new one.
123 * PUBLIC: int file_init __P((SCR *, FREF *, char *, int));
126 file_init(sp, frp, rcv_name, flags)
136 int fd, exists, open_err, readonly;
137 char *oname, tname[MAXPATHLEN];
139 open_err = readonly = 0;
142 * If the file is a recovery file, let the recovery code handle it.
143 * Clear the FR_RECOVER flag first -- the recovery code does set up,
144 * and then calls us! If the recovery call fails, it's probably
145 * because the named file doesn't exist. So, move boldly forward,
146 * presuming that there's an error message the user will get to see.
148 if (F_ISSET(frp, FR_RECOVER)) {
149 F_CLR(frp, FR_RECOVER);
150 return (rcv_read(sp, frp));
154 * Required FRP initialization; the only flag we keep is the
155 * cursor information.
157 F_CLR(frp, ~FR_CURSORSET);
160 * Required EXF initialization:
161 * Flush the line caches.
162 * Default recover mail file fd to -1.
163 * Set initial EXF flag bits.
165 CALLOC_RET(sp, ep, EXF *, 1, sizeof(EXF));
166 ep->c_lno = ep->c_nlines = OOBLNO;
167 ep->rcv_fd = ep->fcntl_fd = -1;
168 F_SET(ep, F_FIRSTMODIFY);
171 * Scan the user's path to find the file that we're going to
174 if (file_spath(sp, frp, &sb, &exists))
178 * If no name or backing file, for whatever reason, create a backing
179 * temporary file, saving the temp file name so we can later unlink
180 * it. If the user never named this file, copy the temporary file name
181 * to the real name (we display that until the user renames it).
184 if (LF_ISSET(FS_OPENERR) || oname == NULL || !exists) {
185 if (opts_empty(sp, O_DIRECTORY, 0))
187 (void)snprintf(tname, sizeof(tname),
188 "%s/vi.XXXXXXXXXX", O_STR(sp, O_DIRECTORY));
189 if ((fd = mkstemp(tname)) == -1) {
191 "237|Unable to create temporary file");
196 if (frp->name == NULL)
197 F_SET(frp, FR_TMPFILE);
198 if ((frp->tname = strdup(tname)) == NULL ||
199 frp->name == NULL && (frp->name = strdup(tname)) == NULL) {
200 if (frp->tname != NULL)
202 msgq(sp, M_SYSERR, NULL);
208 if (!LF_ISSET(FS_OPENERR))
209 F_SET(frp, FR_NEWFILE);
215 * A seat of the pants calculation: try to keep the file in
216 * 15 pages or less. Don't use a page size larger than 10K
217 * (vi should have good locality) or smaller than 1K.
219 psize = ((sb.st_size / 15) + 1023) / 1024;
227 ep->mdev = sb.st_dev;
228 ep->minode = sb.st_ino;
230 ep->mtime = sb.st_mtime;
232 if (!S_ISREG(sb.st_mode))
233 msgq_str(sp, M_ERR, oname,
234 "238|Warning: %s is not a regular file");
237 /* Set up recovery. */
238 memset(&oinfo, 0, sizeof(RECNOINFO));
239 oinfo.bval = '\n'; /* Always set. */
241 oinfo.flags = F_ISSET(sp->gp, G_SNAPSHOT) ? R_SNAPSHOT : 0;
242 if (rcv_name == NULL) {
243 if (!rcv_tmp(sp, ep, frp->name))
244 oinfo.bfname = ep->rcv_path;
246 if ((ep->rcv_path = strdup(rcv_name)) == NULL) {
247 msgq(sp, M_SYSERR, NULL);
250 oinfo.bfname = ep->rcv_path;
251 F_SET(ep, F_MODIFIED);
254 /* Open a db structure. */
255 if ((ep->db = dbopen(rcv_name == NULL ? oname : NULL,
256 O_NONBLOCK | O_RDONLY,
257 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH,
258 DB_RECNO, &oinfo)) == NULL) {
260 M_SYSERR, rcv_name == NULL ? oname : rcv_name, "%s");
263 * Historically, vi permitted users to edit files that couldn't
264 * be read. This isn't useful for single files from a command
265 * line, but it's quite useful for "vi *.c", since you can skip
266 * past files that you can't read.
273 * Do the remaining things that can cause failure of the new file,
274 * mark and logging initialization.
276 if (mark_init(sp, ep) || log_init(sp, ep))
280 * Set the alternate file name to be the file we're discarding.
283 * Temporary files can't become alternate files, so there's no file
284 * name. This matches historical practice, although it could only
285 * happen in historical vi as the result of the initial command, i.e.
286 * if vi was executed without a file name.
288 if (LF_ISSET(FS_SETALT))
289 set_alt_name(sp, sp->frp == NULL ||
290 F_ISSET(sp->frp, FR_TMPFILE) ? NULL : sp->frp->name);
293 * Close the previous file; if that fails, close the new one and run
297 * There's a nasty special case. If the user edits a temporary file,
298 * and then does an ":e! %", we need to re-initialize the backing
299 * file, but we can't change the name. (It's worse -- we're dealing
300 * with *names* here, we can't even detect that it happened.) Set a
301 * flag so that the file_end routine ignores the backing information
302 * of the old file if it happens to be the same as the new one.
305 * Side-effect: after the call to file_end(), sp->frp may be NULL.
307 if (sp->ep != NULL) {
308 F_SET(frp, FR_DONTDELETE);
309 if (file_end(sp, NULL, LF_ISSET(FS_FORCE))) {
310 (void)file_end(sp, ep, 1);
313 F_CLR(frp, FR_DONTDELETE);
317 * Lock the file; if it's a recovery file, it should already be
318 * locked. Note, we acquire the lock after the previous file
319 * has been ended, so that we don't get an "already locked" error
323 * While the user can't interrupt us between the open and here,
324 * there's a race between the dbopen() and the lock. Not much
325 * we can do about it.
328 * We don't make a big deal of not being able to lock the file. As
329 * locking rarely works over NFS, and often fails if the file was
330 * mmap(2)'d, it's far too common to do anything like print an error
331 * message, let alone make the file readonly. At some future time,
332 * when locking is a little more reliable, this should change to be
335 if (rcv_name == NULL)
336 switch (file_lock(sp, oname,
337 &ep->fcntl_fd, ep->db->fd(ep->db), 0)) {
339 F_SET(frp, FR_UNLOCKED);
343 msgq_str(sp, M_INFO, oname,
344 "239|%s already locked, session is read-only");
351 * Historically, the readonly edit option was set per edit buffer in
352 * vi, unless the -R command-line option was specified or the program
353 * was executed as "view". (Well, to be truthful, if the letter 'w'
354 * occurred anywhere in the program name, but let's not get into that.)
355 * So, the persistant readonly state has to be stored in the screen
356 * structure, and the edit option value toggles with the contents of
357 * the edit buffer. If the persistant readonly flag is set, set the
358 * readonly edit option.
360 * Otherwise, try and figure out if a file is readonly. This is a
361 * dangerous thing to do. The kernel is the only arbiter of whether
362 * or not a file is writeable, and the best that a user program can
363 * do is guess. Obvious loopholes are files that are on a file system
364 * mounted readonly (access catches this one on a few systems), or
365 * alternate protection mechanisms, ACL's for example, that we can't
366 * portably check. Lots of fun, and only here because users whined.
369 * Historic vi displayed the readonly message if none of the file
370 * write bits were set, or if an an access(2) call on the path
371 * failed. This seems reasonable. If the file is mode 444, root
372 * users may want to know that the owner of the file did not expect
375 * Historic vi set the readonly bit if no write bits were set for
376 * a file, even if the access call would have succeeded. This makes
377 * the superuser force the write even when vi expects that it will
378 * succeed. I'm less supportive of this semantic, but it's historic
379 * practice and the conservative approach to vi'ing files as root.
381 * It would be nice if there was some way to update this when the user
382 * does a "^Z; chmod ...". The problem is that we'd first have to
383 * distinguish between readonly bits set because of file permissions
384 * and those set for other reasons. That's not too hard, but deciding
385 * when to reevaluate the permissions is trickier. An alternative
386 * might be to turn off the readonly bit if the user forces a write
390 * Access(2) doesn't consider the effective uid/gid values. This
391 * probably isn't a problem for vi when it's running standalone.
393 if (readonly || F_ISSET(sp, SC_READONLY) ||
394 !F_ISSET(frp, FR_NEWFILE) &&
395 (!(sb.st_mode & (S_IWUSR | S_IWGRP | S_IWOTH)) ||
396 access(frp->name, W_OK)))
397 O_SET(sp, O_READONLY);
399 O_CLR(sp, O_READONLY);
406 /* Set the initial cursor position, queue initial command. */
409 /* Redraw the screen from scratch, schedule a welcome message. */
410 F_SET(sp, SC_SCR_REFORMAT | SC_STATUS);
414 err: if (frp->name != NULL) {
418 if (frp->tname != NULL) {
419 (void)unlink(frp->tname);
424 oerr: if (F_ISSET(ep, F_RCV_ON))
425 (void)unlink(ep->rcv_path);
426 if (ep->rcv_path != NULL) {
431 (void)ep->db->close(ep->db);
435 file_init(sp, frp, rcv_name, flags | FS_OPENERR) : 1);
440 * Scan the user's path to find the file that we're going to
444 file_spath(sp, frp, sbp, existsp)
453 char *name, *p, *t, path[MAXPATHLEN];
456 * If the name is NULL or an explicit reference (i.e., the first
457 * component is . or ..) ignore the O_PATH option.
464 if (name[0] == '/' || name[0] == '.' &&
465 (name[1] == '/' || name[1] == '.' && name[2] == '/')) {
466 *existsp = !stat(name, sbp);
471 if (!stat(name, sbp)) {
476 /* Try the O_PATH option values. */
477 for (found = 0, p = t = O_STR(sp, O_PATH);; ++p)
478 if (*p == ':' || *p == '\0') {
483 sizeof(path), "%s/%s", t, name);
485 if (!stat(path, sbp)) {
495 /* If we found it, build a new pathname and discard the old one. */
497 MALLOC_RET(sp, p, char *, len + 1);
498 memcpy(p, path, len + 1);
508 * Set up the initial cursor position.
519 /* Set some basic defaults. */
524 * Historically, initial commands (the -c option) weren't executed
525 * until a file was loaded, e.g. "vi +10 nofile", followed by an
526 * :edit or :tag command, would execute the +10 on the file loaded
527 * by the subsequent command, (assuming that it existed). This
528 * applied as well to files loaded using the tag commands, and we
529 * follow that historic practice. Also, all initial commands were
530 * ex commands and were always executed on the last line of the file.
532 * Otherwise, if no initial command for this file:
533 * If in ex mode, move to the last line, first nonblank character.
534 * If the file has previously been edited, move to the last known
535 * position, and check it for validity.
536 * Otherwise, move to the first line, first nonblank.
538 * This gets called by the file init code, because we may be in a
539 * file of ex commands and we want to execute them from the right
540 * location in the file.
544 if (gp->c_option != NULL && !F_ISSET(sp->frp, FR_NEWFILE)) {
545 if (db_last(sp, &sp->lno))
552 "-c option", gp->c_option, strlen(gp->c_option), 1, 1))
555 } else if (F_ISSET(sp, SC_EX)) {
556 if (db_last(sp, &sp->lno))
565 if (F_ISSET(sp->frp, FR_CURSORSET)) {
566 sp->lno = sp->frp->lno;
567 sp->cno = sp->frp->cno;
569 /* If returning to a file in vi, center the line. */
570 F_SET(sp, SC_SCR_CENTER);
572 if (O_ISSET(sp, O_COMMENT))
578 if (db_get(sp, sp->lno, 0, NULL, &len)) {
583 if (!nb && sp->cno > len)
588 (void)nonblank(sp, sp->lno, &sp->cno);
593 * The initial column is also the most attractive column.
599 * Historically, vi initialized the absolute mark, but ex did not.
600 * Which meant, that if the first command in ex mode was "visual",
601 * or if an ex command was executed first (e.g. vi +10 file) vi was
602 * entered without the mark being initialized. For consistency, if
603 * the file isn't empty, we initialize it for everyone, believing
604 * that it can't hurt, and is generally useful. Not initializing it
605 * if the file is empty is historic practice, although it has always
606 * been possible to set (and use) marks in empty vi files.
610 (void)mark_set(sp, ABSMARK1, &m, 0);
615 * Stop editing a file.
617 * PUBLIC: int file_end __P((SCR *, EXF *, int));
620 file_end(sp, ep, force)
629 * ep MAY NOT BE THE SAME AS sp->ep, DON'T USE THE LATTER.
630 * (If argument ep is NULL, use sp->ep.)
632 * If multiply referenced, just decrement the count and return.
636 if (--ep->refcnt != 0)
641 * Clean up the FREF structure.
643 * Save the cursor location.
646 * It would be cleaner to do this somewhere else, but by the time
647 * ex or vi knows that we're changing files it's already happened.
652 F_SET(frp, FR_CURSORSET);
655 * We may no longer need the temporary backing file, so clean it
656 * up. We don't need the FREF structure either, if the file was
657 * never named, so lose it.
660 * Re: FR_DONTDELETE, see the comment above in file_init().
662 if (!F_ISSET(frp, FR_DONTDELETE) && frp->tname != NULL) {
663 if (unlink(frp->tname))
664 msgq_str(sp, M_SYSERR, frp->tname, "240|%s: remove");
667 if (F_ISSET(frp, FR_TMPFILE)) {
668 CIRCLEQ_REMOVE(&sp->gp->frefq, frp, q);
669 if (frp->name != NULL)
677 * Clean up the EXF structure.
679 * Close the db structure.
681 if (ep->db->close != NULL && ep->db->close(ep->db) && !force) {
682 msgq_str(sp, M_SYSERR, frp->name, "241|%s: close");
687 /* COMMITTED TO THE CLOSE. THERE'S NO GOING BACK... */
690 (void)log_end(sp, ep);
692 /* Free up any marks. */
693 (void)mark_end(sp, ep);
696 * Delete recovery files, close the open descriptor, free recovery
697 * memory. See recover.c for a description of the protocol.
700 * Unlink backup file first, we can detect that the recovery file
701 * doesn't reference anything when the user tries to recover it.
702 * There's a race, here, obviously, but it's fairly small.
704 if (!F_ISSET(ep, F_RCV_NORM)) {
705 if (ep->rcv_path != NULL && unlink(ep->rcv_path))
706 msgq_str(sp, M_SYSERR, ep->rcv_path, "242|%s: remove");
707 if (ep->rcv_mpath != NULL && unlink(ep->rcv_mpath))
708 msgq_str(sp, M_SYSERR, ep->rcv_mpath, "243|%s: remove");
710 if (ep->fcntl_fd != -1)
711 (void)close(ep->fcntl_fd);
712 if (ep->rcv_fd != -1)
713 (void)close(ep->rcv_fd);
714 if (ep->rcv_path != NULL)
716 if (ep->rcv_mpath != NULL)
725 * Write the file to disk. Historic vi had fairly convoluted
726 * semantics for whether or not writes would happen. That's
729 * PUBLIC: int file_write __P((SCR *, MARK *, MARK *, char *, int));
732 file_write(sp, fm, tm, name, flags)
738 enum { NEWFILE, OLDFILE } mtype;
746 int fd, nf, noname, oflags, rval;
747 char *p, *s, *t, buf[MAXPATHLEN + 64];
754 * Writing '%', or naming the current file explicitly, has the
755 * same semantics as writing without a name.
757 if (name == NULL || !strcmp(name, frp->name)) {
763 /* Can't write files marked read-only, unless forced. */
764 if (!LF_ISSET(FS_FORCE) && noname && O_ISSET(sp, O_READONLY)) {
765 msgq(sp, M_ERR, LF_ISSET(FS_POSSIBLE) ?
766 "244|Read-only file, not written; use ! to override" :
767 "245|Read-only file, not written");
771 /* If not forced, not appending, and "writeany" not set ... */
772 if (!LF_ISSET(FS_FORCE | FS_APPEND) && !O_ISSET(sp, O_WRITEANY)) {
773 /* Don't overwrite anything but the original file. */
774 if ((!noname || F_ISSET(frp, FR_NAMECHANGE)) &&
776 msgq_str(sp, M_ERR, name,
777 LF_ISSET(FS_POSSIBLE) ?
778 "246|%s exists, not written; use ! to override" :
779 "247|%s exists, not written");
784 * Don't write part of any existing file. Only test for the
785 * original file, the previous test catches anything else.
787 if (!LF_ISSET(FS_ALL) && noname && !stat(name, &sb)) {
788 msgq(sp, M_ERR, LF_ISSET(FS_POSSIBLE) ?
789 "248|Partial file, not written; use ! to override" :
790 "249|Partial file, not written");
796 * Figure out if the file already exists -- if it doesn't, we display
797 * the "new file" message. The stat might not be necessary, but we
798 * just repeat it because it's easier than hacking the previous tests.
799 * The information is only used for the user message and modification
800 * time test, so we can ignore the obvious race condition.
802 * One final test. If we're not forcing or appending the current file,
803 * and we have a saved modification time, object if the file changed
804 * since we last edited or wrote it, and make them force it.
809 if (noname && !LF_ISSET(FS_FORCE | FS_APPEND) &&
810 (F_ISSET(ep, F_DEVSET) &&
811 (sb.st_dev != ep->mdev || sb.st_ino != ep->minode) ||
812 sb.st_mtime != ep->mtime)) {
813 msgq_str(sp, M_ERR, name, LF_ISSET(FS_POSSIBLE) ?
814 "250|%s: file modified more recently than this copy; use ! to override" :
815 "251|%s: file modified more recently than this copy");
822 /* Set flags to create, write, and either append or truncate. */
823 oflags = O_CREAT | O_WRONLY |
824 (LF_ISSET(FS_APPEND) ? O_APPEND : O_TRUNC);
826 /* Backup the file if requested. */
827 if (!opts_empty(sp, O_BACKUP, 1) &&
828 file_backup(sp, name, O_STR(sp, O_BACKUP)) && !LF_ISSET(FS_FORCE))
833 if ((fd = open(name, oflags,
834 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)) < 0) {
835 if (errno == EACCES && LF_ISSET(FS_FORCE)) {
837 * If the user owns the file but does not
838 * have write permission on it, grant it
839 * automatically for the duration of the
840 * opening of the file, if possible.
845 if (stat(name, &sb) != 0)
848 if (!(sb.st_mode & S_IWUSR) && sb.st_uid == getuid())
852 if (chmod(name, fmode) != 0)
854 fd = open(name, oflags, S_IRUSR | S_IWUSR |
855 S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
858 (void)fchmod(fd, sb.st_mode);
863 msgq_str(sp, M_SYSERR, name, "%s");
870 /* Try and get a lock. */
871 if (!noname && file_lock(sp, NULL, NULL, fd, 0) == LOCK_UNAVAIL)
872 msgq_str(sp, M_ERR, name,
873 "252|%s: write lock was unavailable");
878 * In libc 4.5.x, fdopen(fd, "w") clears the O_APPEND flag (if set).
879 * This bug is fixed in libc 4.6.x.
881 * This code works around this problem for libc 4.5.x users.
882 * Note that this code is harmless if you're using libc 4.6.x.
884 if (LF_ISSET(FS_APPEND) && lseek(fd, (off_t)0, SEEK_END) < 0) {
885 msgq(sp, M_SYSERR, name);
891 * Use stdio for buffering.
894 * SVR4.2 requires the fdopen mode exactly match the original open
895 * mode, i.e. you have to open with "a" if appending.
897 if ((fp = fdopen(fd, LF_ISSET(FS_APPEND) ? "a" : "w")) == NULL) {
898 msgq_str(sp, M_SYSERR, name, "%s");
903 /* Build fake addresses, if necessary. */
908 if (db_last(sp, &to.lno))
914 rval = ex_writefp(sp, name, fp, fm, tm, &nlno, &nch, 0);
917 * Save the new last modification time -- even if the write fails
918 * we re-init the time. That way the user can clean up the disk
919 * and rewrite without having to force it.
926 ep->mdev = sb.st_dev;
927 ep->minode = sb.st_ino;
929 ep->mtime = sb.st_mtime;
933 * If the write failed, complain loudly. ex_writefp() has already
934 * complained about the actual error, reinforce it if data was lost.
937 if (!LF_ISSET(FS_APPEND))
938 msgq_str(sp, M_ERR, name,
939 "254|%s: WARNING: FILE TRUNCATED");
944 * Once we've actually written the file, it doesn't matter that the
945 * file name was changed -- if it was, we've already whacked it.
947 F_CLR(frp, FR_NAMECHANGE);
950 * If wrote the entire file, and it wasn't by appending it to a file,
951 * clear the modified bit. If the file was written to the original
952 * file name and the file is a temporary, set the "no exit" bit. This
953 * permits the user to write the file and use it in the context of the
954 * filesystem, but still keeps them from discarding their changes by
957 if (LF_ISSET(FS_ALL) && !LF_ISSET(FS_APPEND)) {
958 F_CLR(ep, F_MODIFIED);
959 if (F_ISSET(frp, FR_TMPFILE))
961 F_SET(frp, FR_TMPEXIT);
963 F_CLR(frp, FR_TMPEXIT);
966 p = msg_print(sp, name, &nf);
970 "256|%s: new file: %lu lines, %lu characters", NULL);
971 len = snprintf(buf, sizeof(buf), msgstr, p, nlno, nch);
974 msgstr = msg_cat(sp, LF_ISSET(FS_APPEND) ?
975 "315|%s: appended: %lu lines, %lu characters" :
976 "257|%s: %lu lines, %lu characters", NULL);
977 len = snprintf(buf, sizeof(buf), msgstr, p, nlno, nch);
984 * There's a nasty problem with long path names. Cscope and tags files
985 * can result in long paths and vi will request a continuation key from
986 * the user. Unfortunately, the user has typed ahead, and chaos will
987 * result. If we assume that the characters in the filenames only take
988 * a single screen column each, we can trim the filename.
991 if (len >= sp->cols) {
992 for (s = buf, t = buf + strlen(p); s < t &&
993 (*s != '/' || len >= sp->cols - 3); ++s, --len);
997 *--s = '.'; /* Leading ellipses. */
1002 msgq(sp, M_INFO, "%s", s);
1004 FREE_SPACE(sp, p, 0);
1010 * Backup the about-to-be-written file.
1013 * We do the backup by copying the entire file. It would be nice to do
1014 * a rename instead, but: (1) both files may not fit and we want to fail
1015 * before doing the rename; (2) the backup file may not be on the same
1016 * disk partition as the file being written; (3) there may be optional
1017 * file information (MACs, DACs, whatever) that we won't get right if we
1018 * recreate the file. So, let's not risk it.
1021 file_backup(sp, name, bname)
1031 int flags, maxnum, nr, num, nw, rfd, wfd, version;
1032 char *bp, *estr, *p, *pct, *slash, *t, *wfname, buf[8192];
1035 bp = estr = wfname = NULL;
1038 * Open the current file for reading. Do this first, so that
1039 * we don't exec a shell before the most likely failure point.
1040 * If it doesn't exist, it's okay, there's just nothing to back
1044 if ((rfd = open(name, O_RDONLY, 0)) < 0) {
1045 if (errno == ENOENT)
1052 * If the name starts with an 'N' character, add a version number
1053 * to the name. Strip the leading N from the string passed to the
1054 * expansion routines, for no particular reason. It would be nice
1055 * to permit users to put the version number anywhere in the backup
1056 * name, but there isn't a special character that we can use in the
1057 * name, and giving a new character a special meaning leads to ugly
1058 * hacks both here and in the supporting ex routines.
1060 * Shell and file name expand the option's value.
1062 argv_init(sp, &cmd);
1063 ex_cinit(&cmd, 0, 0, 0, 0, 0, NULL);
1064 if (bname[0] == 'N') {
1069 if (argv_exp2(sp, &cmd, bname, strlen(bname)))
1073 * 0 args: impossible.
1075 * >1 args: object, too many args.
1077 if (cmd.argc != 1) {
1078 msgq_str(sp, M_ERR, bname,
1079 "258|%s expanded into too many file names");
1085 * If appending a version number, read through the directory, looking
1086 * for file names that match the name followed by a number. Make all
1087 * of the other % characters in name literal, so the user doesn't get
1088 * surprised and sscanf doesn't drop core indirecting through pointers
1089 * that don't exist. If any such files are found, increment its number
1093 GET_SPACE_GOTO(sp, bp, blen, cmd.argv[0]->len * 2 + 50);
1094 for (t = bp, slash = NULL,
1095 p = cmd.argv[0]->bp; p[0] != '\0'; *t++ = *p++)
1099 } else if (p[0] == '/')
1106 if (slash == NULL) {
1107 dirp = opendir(".");
1116 estr = cmd.argv[0]->bp;
1120 for (maxnum = 0; (dp = readdir(dirp)) != NULL;)
1121 if (sscanf(dp->d_name, p, &num) == 1 && num > maxnum)
1123 (void)closedir(dirp);
1125 /* Format the backup file name. */
1126 (void)snprintf(pct, blen - (pct - bp), "%d", maxnum + 1);
1130 wfname = cmd.argv[0]->bp;
1133 /* Open the backup file, avoiding lurkers. */
1134 if (stat(wfname, &sb) == 0) {
1135 if (!S_ISREG(sb.st_mode)) {
1136 msgq_str(sp, M_ERR, bname,
1137 "259|%s: not a regular file");
1140 if (sb.st_uid != getuid()) {
1141 msgq_str(sp, M_ERR, bname, "260|%s: not owned by you");
1144 if (sb.st_mode & (S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)) {
1145 msgq_str(sp, M_ERR, bname,
1146 "261|%s: accessible by a user other than the owner");
1151 flags = O_CREAT | O_EXCL;
1152 if ((wfd = open(wfname, flags | O_WRONLY, S_IRUSR | S_IWUSR)) < 0) {
1157 /* Copy the file's current contents to its backup value. */
1158 while ((nr = read(rfd, buf, sizeof(buf))) > 0)
1159 for (off = 0; nr != 0; nr -= nw, off += nw)
1160 if ((nw = write(wfd, buf + off, nr)) < 0) {
1178 FREE_SPACE(sp, bp, blen);
1185 (void)unlink(wfname);
1189 msgq_str(sp, M_SYSERR, estr, "%s");
1191 FREE_SPACE(sp, bp, blen);
1197 * Skip the first comment.
1207 for (lno = 1; !db_get(sp, lno, 0, &p, &len) && len == 0; ++lno);
1211 F_SET(sp, SC_SCR_TOP);
1212 while (!db_get(sp, ++lno, 0, &p, &len))
1213 if (len < 1 || p[0] != '#') {
1217 } else if (len > 1 && p[0] == '/' && p[1] == '*') {
1218 F_SET(sp, SC_SCR_TOP);
1220 for (; len > 1; --len, ++p)
1221 if (p[0] == '*' && p[1] == '/') {
1225 } while (!db_get(sp, ++lno, 0, &p, &len));
1226 } else if (len > 1 && p[0] == '/' && p[1] == '/') {
1227 F_SET(sp, SC_SCR_TOP);
1231 for (; len > 1; --len, ++p)
1232 if (p[0] == '/' && p[1] == '/') {
1236 } while (!db_get(sp, ++lno, 0, &p, &len));
1242 * First modification check routine. The :next, :prev, :rewind, :tag,
1243 * :tagpush, :tagpop, ^^ modifications check.
1245 * PUBLIC: int file_m1 __P((SCR *, int, int));
1248 file_m1(sp, force, flags)
1256 /* If no file loaded, return no modifications. */
1261 * If the file has been modified, we'll want to write it back or
1262 * fail. If autowrite is set, we'll write it back automatically,
1263 * unless force is also set. Otherwise, we fail unless forced or
1264 * there's another open screen on this file.
1266 if (F_ISSET(ep, F_MODIFIED))
1267 if (O_ISSET(sp, O_AUTOWRITE)) {
1268 if (!force && file_aw(sp, flags))
1270 } else if (ep->refcnt <= 1 && !force) {
1271 msgq(sp, M_ERR, LF_ISSET(FS_POSSIBLE) ?
1272 "262|File modified since last complete write; write or use ! to override" :
1273 "263|File modified since last complete write; write or use :edit! to override");
1277 return (file_m3(sp, force));
1282 * Second modification check routine. The :edit, :quit, :recover
1283 * modifications check.
1285 * PUBLIC: int file_m2 __P((SCR *, int));
1296 /* If no file loaded, return no modifications. */
1301 * If the file has been modified, we'll want to fail, unless forced
1302 * or there's another open screen on this file.
1304 if (F_ISSET(ep, F_MODIFIED) && ep->refcnt <= 1 && !force) {
1306 "264|File modified since last complete write; write or use ! to override");
1310 return (file_m3(sp, force));
1315 * Third modification check routine.
1317 * PUBLIC: int file_m3 __P((SCR *, int));
1328 /* If no file loaded, return no modifications. */
1333 * Don't exit while in a temporary files if the file was ever modified.
1334 * The problem is that if the user does a ":wq", we write and quit,
1335 * unlinking the temporary file. Not what the user had in mind at all.
1336 * We permit writing to temporary files, so that user maps using file
1337 * system names work with temporary files.
1339 if (F_ISSET(sp->frp, FR_TMPEXIT) && ep->refcnt <= 1 && !force) {
1341 "265|File is a temporary; exit will discard modifications");
1349 * Autowrite routine. If modified, autowrite is set and the readonly bit
1350 * is not set, write the file. A routine so there's a place to put the
1353 * PUBLIC: int file_aw __P((SCR *, int));
1360 if (!F_ISSET(sp->ep, F_MODIFIED))
1362 if (!O_ISSET(sp, O_AUTOWRITE))
1367 * Historic 4BSD vi attempted to write the file if autowrite was set,
1368 * regardless of the writeability of the file (as defined by the file
1369 * readonly flag). System V changed this as some point, not attempting
1370 * autowrite if the file was readonly. This feels like a bug fix to
1371 * me (e.g. the principle of least surprise is violated if readonly is
1372 * set and vi writes the file), so I'm compatible with System V.
1374 if (O_ISSET(sp, O_READONLY)) {
1376 "266|File readonly, modifications not auto-written");
1379 return (file_write(sp, NULL, NULL, NULL, flags));
1384 * Set the alternate pathname.
1386 * Set the alternate pathname. It's a routine because I wanted some place
1387 * to hang this comment. The alternate pathname (normally referenced using
1388 * the special character '#' during file expansion and in the vi ^^ command)
1389 * is set by almost all ex commands that take file names as arguments. The
1390 * rules go something like this:
1392 * 1: If any ex command takes a file name as an argument (except for the
1393 * :next command), the alternate pathname is set to that file name.
1394 * This excludes the command ":e" and ":w !command" as no file name
1395 * was specified. Note, historically, the :source command did not set
1396 * the alternate pathname. It does in nvi, for consistency.
1398 * 2: However, if any ex command sets the current pathname, e.g. the
1399 * ":e file" or ":rew" commands succeed, then the alternate pathname
1400 * is set to the previous file's current pathname, if it had one.
1401 * This includes the ":file" command and excludes the ":e" command.
1402 * So, by rule #1 and rule #2, if ":edit foo" fails, the alternate
1403 * pathname will be "foo", if it succeeds, the alternate pathname will
1404 * be the previous current pathname. The ":e" command will not set
1405 * the alternate or current pathnames regardless.
1407 * 3: However, if it's a read or write command with a file argument and
1408 * the current pathname has not yet been set, the file name becomes
1409 * the current pathname, and the alternate pathname is unchanged.
1411 * If the user edits a temporary file, there may be times when there is no
1412 * alternative file name. A name argument of NULL turns it off.
1414 * PUBLIC: void set_alt_name __P((SCR *, char *));
1417 set_alt_name(sp, name)
1421 if (sp->alt_name != NULL)
1424 sp->alt_name = NULL;
1425 else if ((sp->alt_name = strdup(name)) == NULL)
1426 msgq(sp, M_SYSERR, NULL);
1431 * Get an exclusive lock on a file.
1434 * The default locking is flock(2) style, not fcntl(2). The latter is
1435 * known to fail badly on some systems, and its only advantage is that
1436 * it occasionally works over NFS.
1438 * Furthermore, the semantics of fcntl(2) are wrong. The problems are
1439 * two-fold: you can't close any file descriptor associated with the file
1440 * without losing all of the locks, and you can't get an exclusive lock
1441 * unless you have the file open for writing. Someone ought to be shot,
1442 * but it's probably too late, they may already have reproduced. To get
1443 * around these problems, nvi opens the files for writing when it can and
1444 * acquires a second file descriptor when it can't. The recovery files
1445 * are examples of the former, they're always opened for writing. The DB
1446 * files can't be opened for writing because the semantics of DB are that
1447 * files opened for writing are flushed back to disk when the DB session
1448 * is ended. So, in that case we have to acquire an extra file descriptor.
1450 * PUBLIC: lockr_t file_lock __P((SCR *, char *, int *, int, int));
1453 file_lock(sp, name, fdp, fd, iswrite)
1456 int *fdp, fd, iswrite;
1458 if (!O_ISSET(sp, O_LOCKFILES))
1459 return (LOCK_SUCCESS);
1461 #ifdef HAVE_LOCK_FLOCK /* Hurrah! We've got flock(2). */
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);
1480 #ifdef HAVE_LOCK_FCNTL /* Gag me. We've got fcntl(2). */
1483 int didopen, sverrno;
1485 arg.l_type = F_WRLCK;
1486 arg.l_whence = 0; /* SEEK_SET */
1487 arg.l_start = arg.l_len = 0;
1491 * If the file descriptor isn't opened for writing, it must fail.
1492 * If we fail because we can't get a read/write file descriptor,
1493 * we return LOCK_SUCCESS, believing that the file is readonly
1494 * and that will be sufficient to warn the user.
1497 if (name == NULL || fdp == NULL)
1498 return (LOCK_FAILED);
1499 if ((fd = open(name, O_RDWR, 0)) == -1)
1500 return (LOCK_SUCCESS);
1506 if (!fcntl(fd, F_SETLK, &arg)) {
1507 fcntl(fd, F_SETFD, 1);
1508 return (LOCK_SUCCESS);
1519 * We need to distinguish a lock not being available for the file
1520 * from the file system not supporting locking. Fcntl is documented
1521 * as returning EACCESS and EAGAIN; add EWOULDBLOCK for good measure,
1522 * and assume they are the former. There's no portable way to do this.
1524 return (errno == EACCES || errno == EAGAIN
1526 || errno == EWOULDBLOCK
1528 ? LOCK_UNAVAIL : LOCK_FAILED);
1531 #if !defined(HAVE_LOCK_FLOCK) && !defined(HAVE_LOCK_FCNTL)
1532 return (LOCK_SUCCESS);