add a routine to search for commands
[nvi.git] / common / exf.c
blob8948570974e74c24e6a33b83aaf69059cca49f30
1 /*-
2 * Copyright (c) 1992, 1993
3 * The Regents of the University of California. All rights reserved.
5 * %sccs.include.redist.c%
6 */
8 #ifndef lint
9 static char sccsid[] = "$Id: exf.c,v 8.62 1993/12/21 11:58:31 bostic Exp $ (Berkeley) $Date: 1993/12/21 11:58:31 $";
10 #endif /* not lint */
12 #include <sys/param.h>
13 #include <sys/stat.h>
16 * We include <sys/file.h>, because the flock(2) #defines were
17 * found there on historical systems. We also include <fcntl.h>
18 * because the open(2) #defines are found there on newer systems.
20 #include <sys/file.h>
22 #include <errno.h>
23 #include <fcntl.h>
24 #include <stdlib.h>
25 #include <string.h>
26 #include <unistd.h>
28 #include "vi.h"
29 #include "excmd.h"
30 #include "pathnames.h"
33 * file_add --
34 * Insert a file name into the FREF list, if it doesn't already
35 * appear in it.
37 * !!!
38 * The "if it doesn't already appear" changes vi's semantics slightly. If
39 * you do a "vi foo bar", and then execute "next bar baz", the edit of bar
40 * will reflect the line/column of the previous edit session. Historic nvi
41 * did not do this. The change is a logical extension of the change where
42 * vi now remembers the last location in any file that it has ever edited,
43 * not just the previously edited file.
45 FREF *
46 file_add(sp, frp_append, name, ignore)
47 SCR *sp;
48 FREF *frp_append;
49 CHAR_T *name;
50 int ignore;
52 FREF *frp;
53 char *p;
56 * Return it if it already exists. Note that we test against the
57 * user's current name, whatever that happens to be, including if
58 * it's a temporary file. If the user is trying to set an argument
59 * list, the ignore argument will be on -- if we're ignoring the
60 * file turn off the ignore bit, so it's back in the argument list.
62 if (name != NULL)
63 for (frp = sp->frefq.cqh_first;
64 frp != (FREF *)&sp->frefq; frp = frp->q.cqe_next)
65 if ((p = FILENAME(frp)) != NULL && !strcmp(p, name)) {
66 if (!ignore)
67 F_CLR(frp, FR_IGNORE);
68 return (frp);
71 /* Allocate and initialize the FREF structure. */
72 CALLOC(sp, frp, FREF *, 1, sizeof(FREF));
73 if (frp == NULL)
74 return (NULL);
77 * If no file name specified, or if the file name is a request
78 * for something temporary, file_init() will allocate the file
79 * name. Temporary files are always ignored.
81 #define TEMPORARY_FILE_STRING "/tmp"
82 if (name != NULL && strcmp(name, TEMPORARY_FILE_STRING) &&
83 (frp->name = strdup(name)) == NULL) {
84 FREE(frp, sizeof(FREF));
85 msgq(sp, M_SYSERR, NULL);
86 return (NULL);
89 /* Only the initial argument list is "remembered". */
90 if (ignore)
91 F_SET(frp, FR_IGNORE);
93 /* Append into the chain of file names. */
94 if (frp_append != NULL) {
95 CIRCLEQ_INSERT_AFTER(&sp->frefq, frp_append, frp, q);
96 } else
97 CIRCLEQ_INSERT_TAIL(&sp->frefq, frp, q);
99 return (frp);
103 * file_first --
104 * Return the first file name for editing, if any.
106 FREF *
107 file_first(sp)
108 SCR *sp;
110 FREF *frp;
112 /* Return the first file name. */
113 for (frp = sp->frefq.cqh_first;
114 frp != (FREF *)&sp->frefq; frp = frp->q.cqe_next)
115 if (!F_ISSET(frp, FR_IGNORE))
116 return (frp);
117 return (NULL);
121 * file_next --
122 * Return the next file name, if any.
124 FREF *
125 file_next(sp, frp)
126 SCR *sp;
127 FREF *frp;
129 while ((frp = frp->q.cqe_next) != (FREF *)&sp->frefq)
130 if (!F_ISSET(frp, FR_IGNORE))
131 return (frp);
132 return (NULL);
136 * file_prev --
137 * Return the previous file name, if any.
139 FREF *
140 file_prev(sp, frp)
141 SCR *sp;
142 FREF *frp;
144 while ((frp = frp->q.cqe_prev) != (FREF *)&sp->frefq)
145 if (!F_ISSET(frp, FR_IGNORE))
146 return (frp);
147 return (NULL);
151 * file_unedited --
152 * Return if there are files that aren't ignored and are unedited.
154 FREF *
155 file_unedited(sp)
156 SCR *sp;
158 FREF *frp;
160 /* Return the next file name. */
161 for (frp = sp->frefq.cqh_first;
162 frp != (FREF *)&sp->frefq; frp = frp->q.cqe_next)
163 if (!F_ISSET(frp, FR_EDITED | FR_IGNORE))
164 return (frp);
165 return (NULL);
169 * file_init --
170 * Start editing a file, based on the FREF structure. If successsful,
171 * let go of any previous file. Don't release the previous file until
172 * absolutely sure we have the new one.
175 file_init(sp, frp, rcv_name, force)
176 SCR *sp;
177 FREF *frp;
178 char *rcv_name;
179 int force;
181 EXF *ep;
182 RECNOINFO oinfo;
183 struct stat sb;
184 size_t psize;
185 int fd;
186 char *p, *oname, tname[MAXPATHLEN];
189 * Required ep initialization:
190 * Flush the line caches.
191 * Default recover mail file fd to -1.
192 * Set initial EXF flag bits.
194 CALLOC_RET(sp, ep, EXF *, 1, sizeof(EXF));
195 ep->c_lno = ep->c_nlines = OOBLNO;
196 ep->rcv_fd = -1;
197 LIST_INIT(&ep->marks);
198 F_SET(ep, F_FIRSTMODIFY);
201 * If no name or backing file, create a backing temporary file, saving
202 * the temp file name so can later unlink it. Repoint the name to the
203 * temporary name (we display it to the user until they rename it).
204 * There are some games we play with the FR_FREE_TNAME and FR_NONAME
205 * flags (see ex/ex_file.c) to make sure that the temporary memory gets
206 * free'd up.
208 if ((oname = FILENAME(frp)) == NULL || stat(oname, &sb)) {
209 (void)snprintf(tname, sizeof(tname),
210 "%s/vi.XXXXXX", O_STR(sp, O_DIRECTORY));
211 if ((fd = mkstemp(tname)) == -1) {
212 msgq(sp, M_SYSERR, "Temporary file");
213 goto err;
215 (void)close(fd);
216 if ((frp->tname = strdup(tname)) == NULL) {
217 msgq(sp, M_SYSERR, NULL);
218 (void)unlink(tname);
219 goto err;
221 oname = frp->tname;
222 psize = 4 * 1024;
223 F_SET(frp, FR_NEWFILE);
224 } else {
225 /* Try to keep it at 10 pages or less per file. */
226 if (sb.st_size < 40 * 1024)
227 psize = 4 * 1024;
228 else if (sb.st_size < 320 * 1024)
229 psize = 32 * 1024;
230 else
231 psize = 64 * 1024;
233 frp->mtime = sb.st_mtime;
236 /* Set up recovery. */
237 memset(&oinfo, 0, sizeof(RECNOINFO));
238 oinfo.bval = '\n'; /* Always set. */
239 oinfo.psize = psize;
240 oinfo.flags = F_ISSET(sp->gp, G_SNAPSHOT) ? R_SNAPSHOT : 0;
241 if (rcv_name == NULL) {
242 if (rcv_tmp(sp, ep, FILENAME(frp)))
243 msgq(sp, M_ERR,
244 "Modifications not recoverable if the system crashes.");
245 else
246 oinfo.bfname = ep->rcv_path;
247 } else if ((ep->rcv_path = strdup(rcv_name)) == NULL) {
248 msgq(sp, M_SYSERR, NULL);
249 goto err;
250 } else {
251 oinfo.bfname = ep->rcv_path;
252 F_SET(ep, F_MODIFIED | F_RCV_ON);
255 /* Open a db structure. */
256 if ((ep->db = dbopen(rcv_name == NULL ? oname : NULL,
257 O_NONBLOCK | O_RDONLY, DEFFILEMODE, DB_RECNO, &oinfo)) == NULL) {
258 msgq(sp, M_SYSERR, rcv_name == NULL ? oname : rcv_name);
259 goto err;
262 /* Init file marks. */
263 if (mark_init(sp, ep))
264 goto err;
266 /* Start logging. */
267 if (log_init(sp, ep))
268 goto err;
271 * The -R flag, or doing a "set readonly" during a session causes
272 * all files edited during the session (using an edit command, or
273 * even using tags) to be marked read-only. Changing the file name
274 * (see ex/ex_file.c), clears this flag.
276 * Otherwise, try and figure out if a file is readonly. This is a
277 * dangerous thing to do. The kernel is the only arbiter of whether
278 * or not a file is writeable, and the best that a user program can
279 * do is guess. Obvious loopholes are files that are on a file system
280 * mounted readonly (access catches this one on a few systems), or
281 * alternate protection mechanisms, ACL's for example, that we can't
282 * portably check. Lots of fun, and only here because users whined.
284 * !!!
285 * Historic vi displayed the readonly message if none of the file
286 * write bits were set, or if an an access(2) call on the path
287 * failed. This seems reasonable. If the file is mode 444, root
288 * users may want to know that the owner of the file did not expect
289 * it to be written.
291 * Historic vi set the readonly bit if no write bits were set for
292 * a file, even if the access call would have succeeded. This makes
293 * the superuser force the write even when vi expects that it will
294 * succeed. I'm less supportive of this semantic, but it's historic
295 * practice and the conservative approach to vi'ing files as root.
297 * It would be nice if there was some way to update this when the user
298 * does a "^Z; chmod ...". The problem is that we'd first have to
299 * distinguish between readonly bits set because of file permissions
300 * and those set for other reasons. That's not too hard, but deciding
301 * when to reevaluate the permissions is trickier. An alternative
302 * might be to turn off the readonly bit if the user forces a write
303 * and it succeeds.
305 * XXX
306 * Access(2) doesn't consider the effective uid/gid values. This
307 * probably isn't a problem for vi when it's running standalone.
309 if (O_ISSET(sp, O_READONLY) || !F_ISSET(frp, FR_NEWFILE) &&
310 (!(sb.st_mode & (S_IWUSR | S_IWGRP | S_IWOTH)) ||
311 access(FILENAME(frp), W_OK)))
312 F_SET(frp, FR_RDONLY);
313 else
314 F_CLR(frp, FR_RDONLY);
317 * Close the previous file; if that fails, close the new one
318 * and run for the border.
320 if (sp->ep != NULL && file_end(sp, sp->ep, force)) {
321 (void)file_end(sp, ep, 1);
322 goto err;
326 * 4.4BSD supports locking in the open call, other systems don't.
327 * Since the user can't interrupt us between the open and here,
328 * it's a don't care.
330 * !!!
331 * We need to distinguish a lock not being available for the file
332 * from the file system not supporting locking. Assume that EAGAIN
333 * is the former. There isn't a portable way to do this.
335 * XXX
336 * The locking is flock(2) style, not fcntl(2). The latter is known
337 * to fail badly on some systems, and its only advantage is that it
338 * occasionally works over NFS.
340 if (flock(ep->db->fd(ep->db), LOCK_EX | LOCK_NB))
341 if (errno == EAGAIN) {
342 msgq(sp, M_INFO,
343 "%s already locked, session is read-only", oname);
344 F_SET(frp, FR_RDONLY);
345 } else
346 msgq(sp, M_VINFO, "%s cannot be locked", oname);
349 * Set the previous file pointer and the alternate file name to be
350 * the file we're about to discard.
352 * !!!
353 * If the current file was a temporary file, the call to file_end()
354 * unlinked it and free'd the name. So, there is no previous file,
355 * and there is no alternate file name. This matches historical
356 * practice, although in historical vi it could only happen as the
357 * result of the initial command, i.e. if vi was execute without a
358 * file name.
360 if (sp->frp != NULL) {
361 p = FILENAME(sp->frp);
362 if (p == NULL)
363 sp->p_frp = NULL;
364 else
365 sp->p_frp = sp->frp;
366 set_alt_name(sp, p);
369 /* The new file has now been officially edited. */
370 F_SET(frp, FR_EDITED);
372 /* Switch... */
373 ++ep->refcnt;
374 sp->ep = ep;
375 sp->frp = frp;
376 return (0);
378 err: if (frp->tname != NULL) {
379 (void)unlink(frp->tname);
380 free(frp->tname);
381 frp->tname = NULL;
383 if (ep->rcv_path != NULL) {
384 free(ep->rcv_path);
385 ep->rcv_path = NULL;
387 FREE(ep, sizeof(EXF));
388 return (1);
392 * file_end --
393 * Stop editing a file.
396 file_end(sp, ep, force)
397 SCR *sp;
398 EXF *ep;
399 int force;
401 FREF *frp;
405 * sp->ep MAY NOT BE THE SAME AS THE ARGUMENT ep, SO DON'T USE IT!
407 * Save the cursor location.
409 * XXX
410 * It would be cleaner to do this somewhere else, but by the time
411 * ex or vi knows that we're changing files it's already happened.
413 frp = sp->frp;
414 frp->lno = sp->lno;
415 frp->cno = sp->cno;
416 F_SET(frp, FR_CURSORSET);
418 /* If multiply referenced, just decrement the count and return. */
419 if (--ep->refcnt != 0)
420 return (0);
422 /* Close the db structure. */
423 if (ep->db->close != NULL && ep->db->close(ep->db) && !force) {
424 msgq(sp, M_ERR,
425 "%s: close: %s", FILENAME(frp), strerror(errno));
426 return (1);
429 /* COMMITTED TO THE CLOSE. THERE'S NO GOING BACK... */
431 /* Stop logging. */
432 (void)log_end(sp, ep);
434 /* Free up any marks. */
435 mark_end(sp, ep);
438 * Delete the recovery files, close the open descriptor,
439 * free recovery memory.
441 if (!F_ISSET(ep, F_RCV_NORM)) {
442 if (ep->rcv_path != NULL && unlink(ep->rcv_path))
443 msgq(sp, M_ERR,
444 "%s: remove: %s", ep->rcv_path, strerror(errno));
445 if (ep->rcv_mpath != NULL && unlink(ep->rcv_mpath))
446 msgq(sp, M_ERR,
447 "%s: remove: %s", ep->rcv_mpath, strerror(errno));
449 if (ep->rcv_fd != -1)
450 (void)close(ep->rcv_fd);
451 if (ep->rcv_path != NULL)
452 free(ep->rcv_path);
453 if (ep->rcv_mpath != NULL)
454 free(ep->rcv_mpath);
457 * Unlink any temporary file, file name. We also turn on the
458 * ignore bit at this point, because it was a "created" file,
459 * not an argument file.
461 if (frp->tname != NULL) {
462 if (unlink(frp->tname))
463 msgq(sp, M_ERR,
464 "%s: remove: %s", frp->tname, strerror(errno));
465 free(frp->tname);
466 frp->tname = NULL;
468 if (frp->name == NULL && frp->cname == NULL)
469 F_SET(frp, FR_IGNORE);
471 /* Free the EXF structure. */
472 FREE(ep, sizeof(EXF));
473 return (0);
477 * file_write --
478 * Write the file to disk. Historic vi had fairly convoluted
479 * semantics for whether or not writes would happen. That's
480 * why all the flags.
483 file_write(sp, ep, fm, tm, name, flags)
484 SCR *sp;
485 EXF *ep;
486 MARK *fm, *tm;
487 char *name;
488 int flags;
490 struct stat sb;
491 FILE *fp;
492 FREF *frp;
493 MARK from, to;
494 u_long nlno, nch;
495 int fd, oflags, rval;
496 char *msg;
499 * Don't permit writing to temporary files. The problem is that
500 * if it's a temp file, and the user does ":wq", we write and quit,
501 * unlinking the temporary file. Not what the user had in mind
502 * at all. This test cannot be forced.
504 frp = sp->frp;
505 if (name == NULL && frp->cname == NULL && frp->name == NULL) {
506 msgq(sp, M_ERR, "No filename to which to write.");
507 return (1);
510 /* Can't write files marked read-only, unless forced. */
511 if (!LF_ISSET(FS_FORCE) &&
512 name == NULL && F_ISSET(frp, FR_RDONLY)) {
513 if (LF_ISSET(FS_POSSIBLE))
514 msgq(sp, M_ERR,
515 "Read-only file, not written; use ! to override.");
516 else
517 msgq(sp, M_ERR,
518 "Read-only file, not written.");
519 return (1);
522 /* If not forced, not appending, and "writeany" not set ... */
523 if (!LF_ISSET(FS_FORCE | FS_APPEND) && !O_ISSET(sp, O_WRITEANY)) {
524 /* Don't overwrite anything but the original file. */
525 if (name != NULL) {
526 if (!stat(name, &sb))
527 goto exists;
528 } else if (frp->cname != NULL &&
529 !F_ISSET(frp, FR_CHANGEWRITE) && !stat(frp->cname, &sb)) {
530 name = frp->cname;
531 exists: if (LF_ISSET(FS_POSSIBLE))
532 msgq(sp, M_ERR,
533 "%s exists, not written; use ! to override.", name);
534 else
535 msgq(sp, M_ERR,
536 "%s exists, not written.", name);
537 return (1);
541 * Don't write part of any existing file. Only test for the
542 * original file, the previous test catches anything else.
544 if (!LF_ISSET(FS_ALL) && name == NULL &&
545 frp->cname == NULL && !stat(frp->name, &sb)) {
546 if (LF_ISSET(FS_POSSIBLE))
547 msgq(sp, M_ERR,
548 "Use ! to write a partial file.");
549 else
550 msgq(sp, M_ERR, "Partial file, not written.");
551 return (1);
556 * Figure out if the file already exists -- if it doesn't, we display
557 * the "new file" message. The stat might not be necessary, but we
558 * just repeat it because it's easier than hacking the previous tests.
559 * The information is only used for the user message and modification
560 * time test, so we can ignore the obvious race condition.
562 * If the user is overwriting a file other than the original file, and
563 * O_WRITEANY was what got us here (neither force nor append was set),
564 * display the "existing file" messsage. Since the FR_CHANGEWRITE flag
565 * is set on a successful write, the message only appears once when the
566 * user changes a file name. This is historic practice.
568 * One final test. If we're not forcing or appending, and we have a
569 * saved modification time, stop the user if it's been written since
570 * we last edited or wrote it, and make them force it.
572 if (stat(name == NULL ? FILENAME(frp) : name, &sb))
573 msg = ": new file";
574 else {
575 msg = "";
576 if (!LF_ISSET(FS_FORCE | FS_APPEND)) {
577 if (frp->mtime && sb.st_mtime > frp->mtime) {
578 msgq(sp, M_ERR,
579 "%s: file modified more recently than this copy%s.",
580 name == NULL ? frp->name : name,
581 LF_ISSET(FS_POSSIBLE) ?
582 "; use ! to override" : "");
583 return (1);
585 if (name != NULL ||
586 !F_ISSET(frp, FR_CHANGEWRITE) && frp->cname != NULL)
587 msg = ": existing file";
591 /* We no longer care where the name came from. */
592 if (name == NULL)
593 name = FILENAME(frp);
595 /* Set flags to either append or truncate. */
596 oflags = O_CREAT | O_WRONLY;
597 if (LF_ISSET(FS_APPEND))
598 oflags |= O_APPEND;
599 else
600 oflags |= O_TRUNC;
602 /* Open the file. */
603 if ((fd = open(name, oflags, DEFFILEMODE)) < 0) {
604 msgq(sp, M_SYSERR, name);
605 return (1);
608 /* Use stdio for buffering. */
609 if ((fp = fdopen(fd, "w")) == NULL) {
610 (void)close(fd);
611 msgq(sp, M_SYSERR, name);
612 return (1);
615 /* Build fake addresses, if necessary. */
616 if (fm == NULL) {
617 from.lno = 1;
618 from.cno = 0;
619 fm = &from;
620 if (file_lline(sp, ep, &to.lno))
621 return (1);
622 to.cno = 0;
623 tm = &to;
626 /* Write the file. */
627 rval = ex_writefp(sp, ep, name, fp, fm, tm, &nlno, &nch);
630 * Save the new last modification time -- even if the write fails
631 * we re-init the time if we wrote anything. That way the user can
632 * clean up the disk and rewrite without having to force it.
634 if (nlno || nch)
635 frp->mtime = stat(name, &sb) ? 0 : sb.st_mtime;
637 /* If the write failed, complain loudly. */
638 if (rval) {
639 if (!LF_ISSET(FS_APPEND))
640 msgq(sp, M_ERR, "%s: WARNING: file truncated!", name);
641 return (1);
645 * Once we've actually written the file, it doesn't matter that the
646 * file name was changed -- if it was, we've already whacked it.
648 F_SET(frp, FR_CHANGEWRITE);
650 /* If wrote the entire file, clear the modified bit. */
651 if (LF_ISSET(FS_ALL))
652 F_CLR(ep, F_MODIFIED);
654 msgq(sp, M_INFO, "%s%s: %lu line%s, %lu characters.",
655 name, msg, nlno, nlno == 1 ? "" : "s", nch);
657 return (0);