/* $NetBSD: exf.c,v 1.8 2014/01/26 21:43:45 christos Exp $ */
/*-
* Copyright (c) 1992, 1993, 1994
* The Regents of the University of California. All rights reserved.
* Copyright (c) 1992, 1993, 1994, 1995, 1996
* Keith Bostic. All rights reserved.
*
* See the LICENSE file for redistribution information.
*/
#include <sys/param.h>
#include <sys/types.h> /* XXX: param.h may not have included types.h */
#include <sys/queue.h>
#include <sys/stat.h>
/*
* We include <sys/file.h>, because the flock(2) and open(2) #defines
* were found there on historical systems. We also include <fcntl.h>
* because the open(2) #defines are found there on newer systems.
*/
#include <sys/file.h>
static int file_backup __P((SCR *, const char *, const char *));
static void file_cinit __P((SCR *));
static void file_comment __P((SCR *));
static int file_spath __P((SCR *, FREF *, struct stat *, int *));
/*
* file_add --
* Insert a file name into the FREF list, if it doesn't already
* appear in it.
*
* !!!
* The "if it doesn't already appear" changes vi's semantics slightly. If
* you do a "vi foo bar", and then execute "next bar baz", the edit of bar
* will reflect the line/column of the previous edit session. Historic nvi
* did not do this. The change is a logical extension of the change where
* vi now remembers the last location in any file that it has ever edited,
* not just the previously edited file.
*
* PUBLIC: FREF *file_add __P((SCR *, const char *));
*/
FREF *
file_add(SCR *sp, const char *name)
{
GS *gp;
FREF *frp, *tfrp;
/*
* Return it if it already exists. Note that we test against the
* user's name, whatever that happens to be, including if it's a
* temporary file.
*
* If the user added a file but was unable to initialize it, there
* can be file list entries where the name field is NULL. Discard
* them the next time we see them.
*/
gp = sp->gp;
if (name != NULL)
TAILQ_FOREACH_SAFE(frp, &gp->frefq, q, tfrp) {
if (frp->name == NULL) {
TAILQ_REMOVE(&gp->frefq, frp, q);
if (frp->name != NULL)
free(frp->name);
free(frp);
continue;
}
if (!strcmp(frp->name, name))
return (frp);
}
/* Allocate and initialize the FREF structure. */
CALLOC(sp, frp, FREF *, 1, sizeof(FREF));
if (frp == NULL)
return (NULL);
/*
* If no file name specified, or if the file name is a request
* for something temporary, file_init() will allocate the file
* name. Temporary files are always ignored.
*/
if (name != NULL && strcmp(name, TEMPORARY_FILE_STRING) &&
(frp->name = strdup(name)) == NULL) {
free(frp);
msgq(sp, M_SYSERR, NULL);
return (NULL);
}
/* Append into the chain of file names. */
TAILQ_INSERT_TAIL(&gp->frefq, frp, q);
return (frp);
}
/*
* file_init --
* Start editing a file, based on the FREF structure. If successsful,
* let go of any previous file. Don't release the previous file until
* absolutely sure we have the new one.
*
* PUBLIC: int file_init __P((SCR *, FREF *, char *, int));
*/
int
file_init(SCR *sp, FREF *frp, char *rcv_name, int flags)
{
EXF *ep;
struct stat sb;
size_t psize;
int fd, exists, open_err, readonly;
char *oname = NULL, tname[MAXPATHLEN];
open_err = readonly = 0;
/*
* If the file is a recovery file, let the recovery code handle it.
* Clear the FR_RECOVER flag first -- the recovery code does set up,
* and then calls us! If the recovery call fails, it's probably
* because the named file doesn't exist. So, move boldly forward,
* presuming that there's an error message the user will get to see.
*/
if (F_ISSET(frp, FR_RECOVER)) {
F_CLR(frp, FR_RECOVER);
return (rcv_read(sp, frp));
}
/*
* Required FRP initialization; the only flag we keep is the
* cursor information.
*/
F_CLR(frp, ~FR_CURSORSET);
/*
* Scan the user's path to find the file that we're going to
* try and open.
*/
if (file_spath(sp, frp, &sb, &exists))
return (1);
/*
* Check whether we already have this file opened in some
* other screen.
*/
if (exists) {
EXF *exfp;
TAILQ_FOREACH(exfp, &sp->gp->exfq, q) {
if (exfp->mdev == sb.st_dev &&
exfp->minode == sb.st_ino &&
(exfp != sp->ep || exfp->refcnt > 1)) {
ep = exfp;
oname = ep->rcv_path;
goto postinit;
}
}
}
/*
* Required EXF initialization:
* Flush the line caches.
* Default recover mail file fd to -1.
* Set initial EXF flag bits.
*/
CALLOC_RET(sp, ep, EXF *, 1, sizeof(EXF));
TAILQ_INIT(&ep->scrq);
sp->c_lno = ep->c_nlines = OOBLNO;
ep->fd = ep->rcv_fd = ep->fcntl_fd = -1;
F_SET(ep, F_FIRSTMODIFY);
/*
* If no name or backing file, for whatever reason, create a backing
* temporary file, saving the temp file name so we can later unlink
* it. If the user never named this file, copy the temporary file name
* to the real name (we display that until the user renames it).
*/
oname = frp->name;
if (LF_ISSET(FS_OPENERR) || oname == NULL || !exists) {
if (opts_empty(sp, O_TMP_DIRECTORY, 0))
goto err;
(void)snprintf(tname, sizeof(tname),
"%s/vi.XXXXXX", O_STR(sp, O_TMP_DIRECTORY));
if ((fd = mkstemp(tname)) == -1) {
msgq(sp, M_SYSERR,
"237|Unable to create temporary file");
goto err;
}
(void)close(fd);
time(&ep->mtime);
} else {
/*
* XXX
* A seat of the pants calculation: try to keep the file in
* 15 pages or less. Don't use a page size larger than 10K
* (vi should have good locality) or smaller than 1K.
*/
psize = ((sb.st_size / 15) + 1023) / 1024;
if (psize > 10)
psize = 10;
if (psize == 0)
psize = 1;
psize *= 1024;
if (!S_ISREG(sb.st_mode))
msgq_str(sp, M_ERR, oname,
"238|Warning: %s is not a regular file");
}
/* Set up recovery. */
if (rcv_name == NULL) {
/* ep->rcv_path NULL if rcv_tmp fails */
rcv_tmp(sp, ep, frp->name);
} else {
if ((ep->rcv_path = strdup(rcv_name)) == NULL) {
msgq(sp, M_SYSERR, NULL);
goto err;
}
F_SET(ep, F_MODIFIED);
}
if (db_init(sp, ep, rcv_name, oname, psize, &open_err)) {
if (open_err && !LF_ISSET(FS_OPENERR))
goto oerr;
goto err;
}
/*
* Do the remaining things that can cause failure of the new file,
* mark and logging initialization.
*/
if (mark_init(sp, ep) || log_init(sp, ep))
goto err;
postinit:
/*
* Set the alternate file name to be the file we're discarding.
*
* !!!
* Temporary files can't become alternate files, so there's no file
* name. This matches historical practice, although it could only
* happen in historical vi as the result of the initial command, i.e.
* if vi was executed without a file name.
*/
if (LF_ISSET(FS_SETALT))
set_alt_name(sp, sp->frp == NULL ||
F_ISSET(sp->frp, FR_TMPFILE) ? NULL : sp->frp->name);
/*
* Close the previous file; if that fails, close the new one and run
* for the border.
*
* !!!
* There's a nasty special case. If the user edits a temporary file,
* and then does an ":e! %", we need to re-initialize the backing
* file, but we can't change the name. (It's worse -- we're dealing
* with *names* here, we can't even detect that it happened.) Set a
* flag so that the file_end routine ignores the backing information
* of the old file if it happens to be the same as the new one.
*
* !!!
* Side-effect: after the call to file_end(), sp->frp may be NULL.
*/
if (sp->ep != NULL) {
F_SET(frp, FR_DONTDELETE);
if (file_end(sp, NULL, LF_ISSET(FS_FORCE))) {
(void)file_end(sp, ep, 1);
goto err;
}
sp->ep = NULL;
F_CLR(frp, FR_DONTDELETE);
}
/*
* Lock the file; if it's a recovery file, it should already be
* locked. Note, we acquire the lock after the previous file
* has been ended, so that we don't get an "already locked" error
* for ":edit!".
*
* XXX
* While the user can't interrupt us between the open and here,
* there's a race between the dbopen() and the lock. Not much
* we can do about it.
*
* XXX
* We don't make a big deal of not being able to lock the file. As
* locking rarely works over NFS, and often fails if the file was
* mmap(2)'d, it's far too common to do anything like print an error
* message, let alone make the file readonly. At some future time,
* when locking is a little more reliable, this should change to be
* an error.
*/
if (rcv_name == NULL && ep->refcnt == 0) {
if ((ep->fd = open(oname, O_RDWR)) == -1)
goto no_lock;
switch (file_lock(sp, oname, &ep->fcntl_fd, ep->fd, 1)) {
case LOCK_FAILED:
no_lock:
F_SET(frp, FR_UNLOCKED);
break;
case LOCK_UNAVAIL:
readonly = 1;
msgq_str(sp, M_INFO, oname,
"239|%s already locked, session is read-only");
break;
case LOCK_SUCCESS:
break;
}
}
/*
* Historically, the readonly edit option was set per edit buffer in
* vi, unless the -R command-line option was specified or the program
* was executed as "view". (Well, to be truthful, if the letter 'w'
* occurred anywhere in the program name, but let's not get into that.)
* So, the persistant readonly state has to be stored in the screen
* structure, and the edit option value toggles with the contents of
* the edit buffer. If the persistant readonly flag is set, set the
* readonly edit option.
*
* Otherwise, try and figure out if a file is readonly. This is a
* dangerous thing to do. The kernel is the only arbiter of whether
* or not a file is writeable, and the best that a user program can
* do is guess. Obvious loopholes are files that are on a file system
* mounted readonly (access catches this one on a few systems), or
* alternate protection mechanisms, ACL's for example, that we can't
* portably check. Lots of fun, and only here because users whined.
*
* !!!
* Historic vi displayed the readonly message if none of the file
* write bits were set, or if an an access(2) call on the path
* failed. This seems reasonable. If the file is mode 444, root
* users may want to know that the owner of the file did not expect
* it to be written.
*
* Historic vi set the readonly bit if no write bits were set for
* a file, even if the access call would have succeeded. This makes
* the superuser force the write even when vi expects that it will
* succeed. I'm less supportive of this semantic, but it's historic
* practice and the conservative approach to vi'ing files as root.
*
* It would be nice if there was some way to update this when the user
* does a "^Z; chmod ...". The problem is that we'd first have to
* distinguish between readonly bits set because of file permissions
* and those set for other reasons. That's not too hard, but deciding
* when to reevaluate the permissions is trickier. An alternative
* might be to turn off the readonly bit if the user forces a write
* and it succeeds.
*
* XXX
* Access(2) doesn't consider the effective uid/gid values. This
* probably isn't a problem for vi when it's running standalone.
*/
if (readonly || F_ISSET(sp, SC_READONLY) ||
(!F_ISSET(frp, FR_NEWFILE) &&
(!(sb.st_mode & (S_IWUSR | S_IWGRP | S_IWOTH)) ||
access(frp->name, W_OK))))
O_SET(sp, O_READONLY);
else
O_CLR(sp, O_READONLY);
/*
* file_spath --
* Scan the user's path to find the file that we're going to
* try and open.
*/
static int
file_spath(SCR *sp, FREF *frp, struct stat *sbp, int *existsp)
{
size_t len;
int found;
char *name, path[MAXPATHLEN];
const char *p, *t;
/*
* If the name is NULL or an explicit reference (i.e., the first
* component is . or ..) ignore the O_PATH option.
*/
name = frp->name;
if (name == NULL) {
*existsp = 0;
return (0);
}
if (name[0] == '/' || (name[0] == '.' &&
(name[1] == '/' || (name[1] == '.' && name[2] == '/')))) {
*existsp = !stat(name, sbp);
return (0);
}
/* Try the O_PATH option values. */
for (found = 0, p = t = O_STR(sp, O_PATH);; ++p)
if (*p == ':' || *p == '\0') {
if (t < p - 1) {
len = snprintf(path, sizeof(path), "%.*s/%s",
(int)(p - t), t, name);
if (!stat(path, sbp)) {
found = 1;
break;
}
}
t = p + 1;
if (*p == '\0')
break;
}
/* If we found it, build a new pathname and discard the old one. */
if (found) {
char *q;
MALLOC_RET(sp, q, char *, len + 1);
memcpy(q, path, len + 1);
free(frp->name);
frp->name = q;
}
*existsp = found;
return (0);
}
/*
* file_cinit --
* Set up the initial cursor position.
*/
static void
file_cinit(SCR *sp)
{
GS *gp;
MARK m;
size_t len;
int nb;
const CHAR_T *wp;
size_t wlen;
/* Set some basic defaults. */
sp->lno = 1;
sp->cno = 0;
/*
* Historically, initial commands (the -c option) weren't executed
* until a file was loaded, e.g. "vi +10 nofile", followed by an
* :edit or :tag command, would execute the +10 on the file loaded
* by the subsequent command, (assuming that it existed). This
* applied as well to files loaded using the tag commands, and we
* follow that historic practice. Also, all initial commands were
* ex commands and were always executed on the last line of the file.
*
* Otherwise, if no initial command for this file:
* If in ex mode, move to the last line, first nonblank character.
* If the file has previously been edited, move to the last known
* position, and check it for validity.
* Otherwise, move to the first line, first nonblank.
*
* This gets called by the file init code, because we may be in a
* file of ex commands and we want to execute them from the right
* location in the file.
*/
nb = 0;
gp = sp->gp;
if (gp->c_option != NULL && !F_ISSET(sp->frp, FR_NEWFILE)) {
if (db_last(sp, &sp->lno))
return;
if (sp->lno == 0) {
sp->lno = 1;
sp->cno = 0;
}
CHAR2INT(sp, gp->c_option, strlen(gp->c_option) + 1,
wp, wlen);
if (ex_run_str(sp, "-c option", wp, wlen - 1, 1, 1))
return;
gp->c_option = NULL;
} else if (F_ISSET(sp, SC_EX)) {
if (db_last(sp, &sp->lno))
return;
if (sp->lno == 0) {
sp->lno = 1;
sp->cno = 0;
return;
}
nb = 1;
} else {
if (F_ISSET(sp->frp, FR_CURSORSET)) {
sp->lno = sp->frp->lno;
sp->cno = sp->frp->cno;
/* If returning to a file in vi, center the line. */
F_SET(sp, SC_SCR_CENTER);
} else {
if (O_ISSET(sp, O_COMMENT))
file_comment(sp);
else
sp->lno = 1;
nb = 1;
}
if (db_get(sp, sp->lno, 0, NULL, &len)) {
sp->lno = 1;
sp->cno = 0;
return;
}
if (!nb && sp->cno > len)
nb = 1;
}
if (nb) {
sp->cno = 0;
(void)nonblank(sp, sp->lno, &sp->cno);
}
/*
* !!!
* The initial column is also the most attractive column.
*/
sp->rcm = sp->cno;
/*
* !!!
* Historically, vi initialized the absolute mark, but ex did not.
* Which meant, that if the first command in ex mode was "visual",
* or if an ex command was executed first (e.g. vi +10 file) vi was
* entered without the mark being initialized. For consistency, if
* the file isn't empty, we initialize it for everyone, believing
* that it can't hurt, and is generally useful. Not initializing it
* if the file is empty is historic practice, although it has always
* been possible to set (and use) marks in empty vi files.
*/
m.lno = sp->lno;
m.cno = sp->cno;
(void)mark_set(sp, ABSMARK1, &m, 0);
}
/*
* file_end --
* Stop editing a file.
*
* PUBLIC: int file_end __P((SCR *, EXF *, int));
*/
int
file_end(SCR *sp, EXF *ep, int force)
{
FREF *frp;
/*
* !!!
* ep MAY NOT BE THE SAME AS sp->ep, DON'T USE THE LATTER.
* (If argument ep is NULL, use sp->ep.)
*
* If multiply referenced, just decrement the count and return.
*/
if (ep == NULL)
ep = sp->ep;
TAILQ_REMOVE(&ep->scrq, sp, eq);
if (--ep->refcnt != 0)
return (0);
/*
*
* Clean up the FREF structure.
*
* Save the cursor location.
*
* XXX
* It would be cleaner to do this somewhere else, but by the time
* ex or vi knows that we're changing files it's already happened.
*/
frp = sp->frp;
frp->lno = sp->lno;
frp->cno = sp->cno;
F_SET(frp, FR_CURSORSET);
/*
* We may no longer need the temporary backing file, so clean it
* up. We don't need the FREF structure either, if the file was
* never named, so lose it.
*
* !!!
* Re: FR_DONTDELETE, see the comment above in file_init().
*/
if (!F_ISSET(frp, FR_DONTDELETE) && frp->tname != NULL) {
if (unlink(frp->tname))
msgq_str(sp, M_SYSERR, frp->tname, "240|%s: remove");
free(frp->tname);
frp->tname = NULL;
if (F_ISSET(frp, FR_TMPFILE)) {
TAILQ_REMOVE(&sp->gp->frefq, frp, q);
if (frp->name != NULL)
free(frp->name);
free(frp);
}
sp->frp = NULL;
}
/*
* Clean up the EXF structure.
*
* Close the db structure.
*/
if (ep->db->close != NULL) {
if ((sp->db_error = db_close(ep->db)) != 0 &&
!force) {
msgq_str(sp, M_DBERR, frp->name, "241|%s: close");
TAILQ_INSERT_HEAD(&ep->scrq, sp, eq);
++ep->refcnt;
return (1);
}
ep->db = NULL;
}
/* COMMITTED TO THE CLOSE. THERE'S NO GOING BACK... */
/*
* Delete recovery files, close the open descriptor, free recovery
* memory. See recover.c for a description of the protocol.
*
* XXX
* Unlink backup file first, we can detect that the recovery file
* doesn't reference anything when the user tries to recover it.
* There's a race, here, obviously, but it's fairly small.
*/
if (!F_ISSET(ep, F_RCV_NORM)) {
if (ep->rcv_path != NULL && unlink(ep->rcv_path))
msgq_str(sp, M_SYSERR, ep->rcv_path, "242|%s: remove");
if (ep->rcv_mpath != NULL && unlink(ep->rcv_mpath))
msgq_str(sp, M_SYSERR, ep->rcv_mpath, "243|%s: remove");
}
TAILQ_REMOVE(&sp->gp->exfq, ep, q);
if (ep->fd != -1)
(void)close(ep->fd);
if (ep->fcntl_fd != -1)
(void)close(ep->fcntl_fd);
if (ep->rcv_fd != -1)
(void)close(ep->rcv_fd);
if (ep->env_path != NULL)
free(ep->env_path);
if (ep->rcv_path != NULL) {
free(ep->rcv_path);
ep->rcv_path = NULL;
}
if (ep->rcv_mpath != NULL)
free(ep->rcv_mpath);
free(ep);
return (0);
}
/*
* file_write --
* Write the file to disk. Historic vi had fairly convoluted
* semantics for whether or not writes would happen. That's
* why all the flags.
*
* PUBLIC: int file_write __P((SCR *, MARK *, MARK *, char *, int));
*/
int
file_write(SCR *sp, MARK *fm, MARK *tm, char *name, int flags)
{
enum { NEWFILE, OLDFILE } mtype;
struct stat sb;
EXF *ep;
FILE *fp;
FREF *frp;
MARK from, to;
size_t len;
u_long nlno, nch;
int fd, nf, noname, oflags, rval;
char *p, *s, *t, buf[MAXPATHLEN + 64];
const char *msgstr;
ep = sp->ep;
frp = sp->frp;
/*
* Writing '%', or naming the current file explicitly, has the
* same semantics as writing without a name.
*/
if (name == NULL || !strcmp(name, frp->name)) {
noname = 1;
name = frp->name;
} else
noname = 0;
/* Can't write files marked read-only, unless forced. */
if (!LF_ISSET(FS_FORCE) && noname && O_ISSET(sp, O_READONLY)) {
msgq(sp, M_ERR, LF_ISSET(FS_POSSIBLE) ?
"244|Read-only file, not written; use ! to override" :
"245|Read-only file, not written");
return (1);
}
/* If not forced, not appending, and "writeany" not set ... */
if (!LF_ISSET(FS_FORCE | FS_APPEND) && !O_ISSET(sp, O_WRITEANY)) {
/* Don't overwrite anything but the original file. */
if ((!noname || F_ISSET(frp, FR_NAMECHANGE)) &&
!stat(name, &sb)) {
msgq_str(sp, M_ERR, name,
LF_ISSET(FS_POSSIBLE) ?
"246|%s exists, not written; use ! to override" :
"247|%s exists, not written");
return (1);
}
/*
* Don't write part of any existing file. Only test for the
* original file, the previous test catches anything else.
*/
if (!LF_ISSET(FS_ALL) && noname && !stat(name, &sb)) {
msgq(sp, M_ERR, LF_ISSET(FS_POSSIBLE) ?
"248|Partial file, not written; use ! to override" :
"249|Partial file, not written");
return (1);
}
}
/*
* Figure out if the file already exists -- if it doesn't, we display
* the "new file" message. The stat might not be necessary, but we
* just repeat it because it's easier than hacking the previous tests.
* The information is only used for the user message and modification
* time test, so we can ignore the obvious race condition.
*
* One final test. If we're not forcing or appending the current file,
* and we have a saved modification time, object if the file changed
* since we last edited or wrote it, and make them force it.
*/
if (stat(name, &sb))
mtype = NEWFILE;
else {
if (noname && !LF_ISSET(FS_FORCE | FS_APPEND) &&
((F_ISSET(ep, F_DEVSET) &&
(sb.st_dev != ep->mdev || sb.st_ino != ep->minode)) ||
sb.st_mtime != ep->mtime)) {
msgq_str(sp, M_ERR, name, LF_ISSET(FS_POSSIBLE) ?
"250|%s: file modified more recently than this copy; use ! to override" :
"251|%s: file modified more recently than this copy");
return (1);
}
mtype = OLDFILE;
}
/* Set flags to create, write, and either append or truncate. */
oflags = O_CREAT | O_WRONLY |
(LF_ISSET(FS_APPEND) ? O_APPEND : O_TRUNC);
/* Backup the file if requested. */
if (!opts_empty(sp, O_BACKUP, 1) &&
file_backup(sp, name, O_STR(sp, O_BACKUP)) && !LF_ISSET(FS_FORCE))
return (1);
/* Try and get a lock. */
if (!noname && file_lock(sp, NULL, NULL, fd, 0) == LOCK_UNAVAIL)
msgq_str(sp, M_ERR, name,
"252|%s: write lock was unavailable");
#if __linux__
/*
* XXX
* In libc 4.5.x, fdopen(fd, "w") clears the O_APPEND flag (if set).
* This bug is fixed in libc 4.6.x.
*
* This code works around this problem for libc 4.5.x users.
* Note that this code is harmless if you're using libc 4.6.x.
*/
if (LF_ISSET(FS_APPEND) && lseek(fd, (off_t)0, SEEK_END) < 0) {
msgq(sp, M_SYSERR, "%s", name);
return (1);
}
#endif
/*
* Use stdio for buffering.
*
* XXX
* SVR4.2 requires the fdopen mode exactly match the original open
* mode, i.e. you have to open with "a" if appending.
*/
if ((fp = fdopen(fd, LF_ISSET(FS_APPEND) ? "a" : "w")) == NULL) {
msgq_str(sp, M_SYSERR, name, "%s");
(void)close(fd);
return (1);
}
/* Build fake addresses, if necessary. */
if (fm == NULL) {
from.lno = 1;
from.cno = 0;
fm = &from;
if (db_last(sp, &to.lno))
return (1);
to.cno = 0;
tm = &to;
}
/*
* Save the new last modification time -- even if the write fails
* we re-init the time. That way the user can clean up the disk
* and rewrite without having to force it.
*/
if (noname) {
if (stat(name, &sb))
time(&ep->mtime);
else {
F_SET(ep, F_DEVSET);
ep->mdev = sb.st_dev;
ep->minode = sb.st_ino;
ep->mtime = sb.st_mtime;
}
}
/*
* If the write failed, complain loudly. ex_writefp() has already
* complained about the actual error, reinforce it if data was lost.
*/
if (rval) {
if (!LF_ISSET(FS_APPEND))
msgq_str(sp, M_ERR, name,
"254|%s: WARNING: FILE TRUNCATED");
return (1);
}
/*
* Once we've actually written the file, it doesn't matter that the
* file name was changed -- if it was, we've already whacked it.
*/
F_CLR(frp, FR_NAMECHANGE);
/*
* If wrote the entire file, and it wasn't by appending it to a file,
* clear the modified bit. If the file was written to the original
* file name and the file is a temporary, set the "no exit" bit. This
* permits the user to write the file and use it in the context of the
* filesystem, but still keeps them from discarding their changes by
* exiting.
*/
if (LF_ISSET(FS_ALL) && !LF_ISSET(FS_APPEND)) {
F_CLR(ep, F_MODIFIED);
if (F_ISSET(frp, FR_TMPFILE)) {
if (noname)
F_SET(frp, FR_TMPEXIT);
else
F_CLR(frp, FR_TMPEXIT);
}
}
/*
* There's a nasty problem with long path names. Cscope and tags files
* can result in long paths and vi will request a continuation key from
* the user. Unfortunately, the user has typed ahead, and chaos will
* result. If we assume that the characters in the filenames only take
* a single screen column each, we can trim the filename.
*/
s = buf;
if (len >= sp->cols) {
for (s = buf, t = buf + strlen(p); s < t &&
(*s != '/' || len >= sp->cols - 3); ++s, --len);
if (s == t)
s = buf;
else {
*--s = '.'; /* Leading ellipses. */
*--s = '.';
*--s = '.';
}
}
msgq(sp, M_INFO, "%s", s);
if (nf)
FREE_SPACE(sp, p, 0);
return (0);
}
/*
* file_backup --
* Backup the about-to-be-written file.
*
* XXX
* We do the backup by copying the entire file. It would be nice to do
* a rename instead, but: (1) both files may not fit and we want to fail
* before doing the rename; (2) the backup file may not be on the same
* disk partition as the file being written; (3) there may be optional
* file information (MACs, DACs, whatever) that we won't get right if we
* recreate the file. So, let's not risk it.
*/
static int
file_backup(SCR *sp, const char *name, const char *bname)
{
struct dirent *dp;
struct stat sb;
DIR *dirp;
EXCMD cmd;
off_t off;
size_t blen;
int flags, maxnum, nr, num, nw, rfd, wfd, version;
char *bp, *pct, *slash, *t, buf[8192];
const char *p, *estr, *wfname;
const CHAR_T *wp;
size_t wlen;
size_t nlen;
char *d = NULL;
rfd = wfd = -1;
estr = wfname = NULL;
bp = NULL;
/*
* Open the current file for reading. Do this first, so that
* we don't exec a shell before the most likely failure point.
* If it doesn't exist, it's okay, there's just nothing to back
* up.
*/
errno = 0;
if ((rfd = open(name, O_RDONLY, 0)) < 0) {
if (errno == ENOENT)
return (0);
estr = name;
goto err;
}
/*
* If the name starts with an 'N' character, add a version number
* to the name. Strip the leading N from the string passed to the
* expansion routines, for no particular reason. It would be nice
* to permit users to put the version number anywhere in the backup
* name, but there isn't a special character that we can use in the
* name, and giving a new character a special meaning leads to ugly
* hacks both here and in the supporting ex routines.
*
* Shell and file name expand the option's value.
*/
ex_cinit(sp, &cmd, 0, 0, 0, 0, 0);
if (bname[0] == 'N') {
version = 1;
++bname;
} else
version = 0;
CHAR2INT(sp, bname, strlen(bname) + 1, wp, wlen);
if (argv_exp2(sp, &cmd, wp, wlen - 1))
return (1);
/*
* 0 args: impossible.
* 1 args: use it.
* >1 args: object, too many args.
*/
if (cmd.argc != 1) {
msgq_str(sp, M_ERR, bname,
"258|%s expanded into too many file names");
(void)close(rfd);
return (1);
}
/*
* If appending a version number, read through the directory, looking
* for file names that match the name followed by a number. Make all
* of the other % characters in name literal, so the user doesn't get
* surprised and sscanf doesn't drop core indirecting through pointers
* that don't exist. If any such files are found, increment its number
* by one.
*/
if (version) {
GET_SPACE_GOTOC(sp, bp, blen, cmd.argv[0]->len * 2 + 50);
INT2SYS(sp, cmd.argv[0]->bp, cmd.argv[0]->len + 1,
p, nlen);
d = strdup(p);
p = d;
for (t = bp, slash = NULL;
p[0] != '\0'; *t++ = *p++)
if (p[0] == '%') {
if (p[1] != '%')
*t++ = '%';
} else if (p[0] == '/')
slash = t;
pct = t;
*t++ = '%';
*t++ = 'd';
*t = '\0';
for (lno = 1; !db_get(sp, lno, 0, &p, &len) && len == 0; ++lno);
if (p == NULL)
return;
if (p[0] == '#') {
F_SET(sp, SC_SCR_TOP);
while (!db_get(sp, ++lno, 0, &p, &len))
if (len < 1 || p[0] != '#') {
sp->lno = lno;
return;
}
} else if (len > 1 && p[0] == '/' && p[1] == '*') {
F_SET(sp, SC_SCR_TOP);
do {
for (; len > 1; --len, ++p)
if (p[0] == '*' && p[1] == '/') {
sp->lno = lno;
return;
}
} while (!db_get(sp, ++lno, 0, &p, &len));
} else if (len > 1 && p[0] == '/' && p[1] == '/') {
F_SET(sp, SC_SCR_TOP);
while (!db_get(sp, ++lno, 0, &p, &len))
if (len < 1 || p[0] != '/' || p[1] != '/') {
sp->lno = lno;
return;
}
}
}
/*
* file_m1 --
* First modification check routine. The :next, :prev, :rewind, :tag,
* :tagpush, :tagpop, ^^ modifications check.
*
* PUBLIC: int file_m1 __P((SCR *, int, int));
*/
int
file_m1(SCR *sp, int force, int flags)
{
EXF *ep;
ep = sp->ep;
/* If no file loaded, return no modifications. */
if (ep == NULL)
return (0);
/*
* If the file has been modified, we'll want to write it back or
* fail. If autowrite is set, we'll write it back automatically,
* unless force is also set. Otherwise, we fail unless forced or
* there's another open screen on this file.
*/
if (F_ISSET(ep, F_MODIFIED)) {
if (O_ISSET(sp, O_AUTOWRITE)) {
if (!force && file_aw(sp, flags))
return (1);
} else if (ep->refcnt <= 1 && !force) {
msgq(sp, M_ERR, LF_ISSET(FS_POSSIBLE) ?
"262|File modified since last complete write; write or use ! to override" :
"263|File modified since last complete write; write or use :edit! to override");
return (1);
}
}
return (file_m3(sp, force));
}
/*
* file_m2 --
* Second modification check routine. The :edit, :quit, :recover
* modifications check.
*
* PUBLIC: int file_m2 __P((SCR *, int));
*/
int
file_m2(SCR *sp, int force)
{
EXF *ep;
ep = sp->ep;
/* If no file loaded, return no modifications. */
if (ep == NULL)
return (0);
/*
* If the file has been modified, we'll want to fail, unless forced
* or there's another open screen on this file.
*/
if (F_ISSET(ep, F_MODIFIED) && ep->refcnt <= 1 && !force) {
msgq(sp, M_ERR,
"264|File modified since last complete write; write or use ! to override");
return (1);
}
return (file_m3(sp, force));
}
/*
* file_m3 --
* Third modification check routine.
*
* PUBLIC: int file_m3 __P((SCR *, int));
*/
int
file_m3(SCR *sp, int force)
{
EXF *ep;
ep = sp->ep;
/* If no file loaded, return no modifications. */
if (ep == NULL)
return (0);
/*
* Don't exit while in a temporary files if the file was ever modified.
* The problem is that if the user does a ":wq", we write and quit,
* unlinking the temporary file. Not what the user had in mind at all.
* We permit writing to temporary files, so that user maps using file
* system names work with temporary files.
*/
if (F_ISSET(sp->frp, FR_TMPEXIT) && ep->refcnt <= 1 && !force) {
msgq(sp, M_ERR,
"265|File is a temporary; exit will discard modifications");
return (1);
}
return (0);
}
/*
* file_aw --
* Autowrite routine. If modified, autowrite is set and the readonly bit
* is not set, write the file. A routine so there's a place to put the
* comment.
*
* PUBLIC: int file_aw __P((SCR *, int));
*/
int
file_aw(SCR *sp, int flags)
{
if (!F_ISSET(sp->ep, F_MODIFIED))
return (0);
if (!O_ISSET(sp, O_AUTOWRITE))
return (0);
/*
* !!!
* Historic 4BSD vi attempted to write the file if autowrite was set,
* regardless of the writeability of the file (as defined by the file
* readonly flag). System V changed this as some point, not attempting
* autowrite if the file was readonly. This feels like a bug fix to
* me (e.g. the principle of least surprise is violated if readonly is
* set and vi writes the file), so I'm compatible with System V.
*/
if (O_ISSET(sp, O_READONLY)) {
msgq(sp, M_INFO,
"266|File readonly, modifications not auto-written");
return (1);
}
return (file_write(sp, NULL, NULL, NULL, flags));
}
/*
* set_alt_name --
* Set the alternate pathname.
*
* Set the alternate pathname. It's a routine because I wanted some place
* to hang this comment. The alternate pathname (normally referenced using
* the special character '#' during file expansion and in the vi ^^ command)
* is set by almost all ex commands that take file names as arguments. The
* rules go something like this:
*
* 1: If any ex command takes a file name as an argument (except for the
* :next command), the alternate pathname is set to that file name.
* This excludes the command ":e" and ":w !command" as no file name
* was specified. Note, historically, the :source command did not set
* the alternate pathname. It does in nvi, for consistency.
*
* 2: However, if any ex command sets the current pathname, e.g. the
* ":e file" or ":rew" commands succeed, then the alternate pathname
* is set to the previous file's current pathname, if it had one.
* This includes the ":file" command and excludes the ":e" command.
* So, by rule #1 and rule #2, if ":edit foo" fails, the alternate
* pathname will be "foo", if it succeeds, the alternate pathname will
* be the previous current pathname. The ":e" command will not set
* the alternate or current pathnames regardless.
*
* 3: However, if it's a read or write command with a file argument and
* the current pathname has not yet been set, the file name becomes
* the current pathname, and the alternate pathname is unchanged.
*
* If the user edits a temporary file, there may be times when there is no
* alternative file name. A name argument of NULL turns it off.
*
* PUBLIC: void set_alt_name __P((SCR *, const char *));
*/
void
set_alt_name(SCR *sp, const char *name)
{
if (sp->alt_name != NULL)
free(sp->alt_name);
if (name == NULL)
sp->alt_name = NULL;
else if ((sp->alt_name = strdup(name)) == NULL)
msgq(sp, M_SYSERR, NULL);
}
/*
* file_lock --
* Get an exclusive lock on a file and set close-on-exec flag
*
* XXX
* The default locking is flock(2) style, not fcntl(2). The latter is
* known to fail badly on some systems, and its only advantage is that
* it occasionally works over NFS.
*
* Furthermore, the semantics of fcntl(2) are wrong. The problems are
* two-fold: you can't close any file descriptor associated with the file
* without losing all of the locks, and you can't get an exclusive lock
* unless you have the file open for writing. Someone ought to be shot,
* but it's probably too late, they may already have reproduced. To get
* around these problems, nvi opens the files for writing when it can and
* acquires a second file descriptor when it can't. The recovery files
* are examples of the former, they're always opened for writing. The DB
* files can't be opened for writing because the semantics of DB are that
* files opened for writing are flushed back to disk when the DB session
* is ended. So, in that case we have to acquire an extra file descriptor.
*
* PUBLIC: lockr_t file_lock __P((SCR *, char *, int *, int, int));
*/
lockr_t
file_lock(SCR *sp, char *name, int *fdp, int fd, int iswrite)
{
fcntl(fd, F_SETFD, 1);
if (!O_ISSET(sp, O_LOCKFILES))
return (LOCK_SUCCESS);
#ifdef HAVE_LOCK_FLOCK /* Hurrah! We've got flock(2). */
/*
* !!!
* We need to distinguish a lock not being available for the file
* from the file system not supporting locking. Flock is documented
* as returning EWOULDBLOCK; add EAGAIN for good measure, and assume
* they are the former. There's no portable way to do this.
*/
errno = 0;
return (flock(fd, LOCK_EX | LOCK_NB) ? errno == EAGAIN
#ifdef EWOULDBLOCK
|| errno == EWOULDBLOCK
#endif
? LOCK_UNAVAIL : LOCK_FAILED : LOCK_SUCCESS);
#endif
#ifdef HAVE_LOCK_FCNTL /* Gag me. We've got fcntl(2). */
{
struct flock arg;
int didopen, sverrno;
/*
* If the file descriptor isn't opened for writing, it must fail.
* If we fail because we can't get a read/write file descriptor,
* we return LOCK_SUCCESS, believing that the file is readonly
* and that will be sufficient to warn the user.
*/
if (!iswrite) {
if (name == NULL || fdp == NULL)
return (LOCK_FAILED);
if ((fd = open(name, O_RDWR, 0)) == -1)
return (LOCK_SUCCESS);
*fdp = fd;
didopen = 1;
}
errno = 0;
if (!fcntl(fd, F_SETLK, &arg))
return (LOCK_SUCCESS);
if (didopen) {
sverrno = errno;
(void)close(fd);
errno = sverrno;
}
/*
* !!!
* We need to distinguish a lock not being available for the file
* from the file system not supporting locking. Fcntl is documented
* as returning EACCESS and EAGAIN; add EWOULDBLOCK for good measure,
* and assume they are the former. There's no portable way to do this.
*/
return (errno == EACCES || errno == EAGAIN
#ifdef EWOULDBLOCK
|| errno == EWOULDBLOCK
#endif
? LOCK_UNAVAIL : LOCK_FAILED);
}
#endif
#if !defined(HAVE_LOCK_FLOCK) && !defined(HAVE_LOCK_FCNTL)
return (LOCK_SUCCESS);
#endif
}
