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Diffstat (limited to 'contrib/nvi/common/exf.c')
| -rw-r--r-- | contrib/nvi/common/exf.c | 1498 |
1 files changed, 1498 insertions, 0 deletions
diff --git a/contrib/nvi/common/exf.c b/contrib/nvi/common/exf.c new file mode 100644 index 0000000..2993b0f --- /dev/null +++ b/contrib/nvi/common/exf.c @@ -0,0 +1,1498 @@ +/*- + * 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 "config.h" + +#ifndef lint +static const char sccsid[] = "@(#)exf.c 10.49 (Berkeley) 10/10/96"; +#endif /* not lint */ + +#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> + +#include <bitstring.h> +#include <dirent.h> +#include <errno.h> +#include <fcntl.h> +#include <limits.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "common.h" + +static int file_backup __P((SCR *, char *, 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 *, CHAR_T *)); + */ +FREF * +file_add(sp, name) + SCR *sp; + CHAR_T *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) + for (frp = gp->frefq.cqh_first; + frp != (FREF *)&gp->frefq; frp = frp->q.cqe_next) { + if (frp->name == NULL) { + tfrp = frp->q.cqe_next; + CIRCLEQ_REMOVE(&gp->frefq, frp, q); + if (frp->name != NULL) + free(frp->name); + free(frp); + frp = tfrp; + 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. */ + CIRCLEQ_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(sp, frp, rcv_name, flags) + SCR *sp; + FREF *frp; + char *rcv_name; + int flags; +{ + EXF *ep; + RECNOINFO oinfo; + struct stat sb; + size_t psize; + int fd, exists, open_err, readonly; + char *oname, 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); + + /* + * 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)); + ep->c_lno = ep->c_nlines = OOBLNO; + ep->rcv_fd = ep->fcntl_fd = -1; + F_SET(ep, F_FIRSTMODIFY); + + /* + * 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); + + /* + * 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_DIRECTORY, 0)) + goto err; + (void)snprintf(tname, sizeof(tname), + "%s/vi.XXXXXX", O_STR(sp, O_DIRECTORY)); + if ((fd = mkstemp(tname)) == -1) { + msgq(sp, M_SYSERR, + "237|Unable to create temporary file"); + goto err; + } + (void)close(fd); + + if (frp->name == NULL) + F_SET(frp, FR_TMPFILE); + if ((frp->tname = strdup(tname)) == NULL || + frp->name == NULL && (frp->name = strdup(tname)) == NULL) { + if (frp->tname != NULL) + free(frp->tname); + msgq(sp, M_SYSERR, NULL); + (void)unlink(tname); + goto err; + } + oname = frp->tname; + psize = 1024; + if (!LF_ISSET(FS_OPENERR)) + F_SET(frp, FR_NEWFILE); + + 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; + + F_SET(ep, F_DEVSET); + ep->mdev = sb.st_dev; + ep->minode = sb.st_ino; + + ep->mtime = sb.st_mtime; + + if (!S_ISREG(sb.st_mode)) + msgq_str(sp, M_ERR, oname, + "238|Warning: %s is not a regular file"); + } + + /* Set up recovery. */ + memset(&oinfo, 0, sizeof(RECNOINFO)); + oinfo.bval = '\n'; /* Always set. */ + oinfo.psize = psize; + oinfo.flags = F_ISSET(sp->gp, G_SNAPSHOT) ? R_SNAPSHOT : 0; + if (rcv_name == NULL) { + if (!rcv_tmp(sp, ep, frp->name)) + oinfo.bfname = ep->rcv_path; + } else { + if ((ep->rcv_path = strdup(rcv_name)) == NULL) { + msgq(sp, M_SYSERR, NULL); + goto err; + } + oinfo.bfname = ep->rcv_path; + F_SET(ep, F_MODIFIED); + } + + /* Open a db structure. */ + if ((ep->db = dbopen(rcv_name == NULL ? oname : NULL, + O_NONBLOCK | O_RDONLY, + S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH, + DB_RECNO, &oinfo)) == NULL) { + msgq_str(sp, + M_SYSERR, rcv_name == NULL ? oname : rcv_name, "%s"); + /* + * !!! + * Historically, vi permitted users to edit files that couldn't + * be read. This isn't useful for single files from a command + * line, but it's quite useful for "vi *.c", since you can skip + * past files that you can't read. + */ + open_err = 1; + goto oerr; + } + + /* + * 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; + + /* + * 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; + } + 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) + switch (file_lock(sp, oname, + &ep->fcntl_fd, ep->db->fd(ep->db), 0)) { + case LOCK_FAILED: + 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); + + /* Switch... */ + ++ep->refcnt; + sp->ep = ep; + sp->frp = frp; + + /* Set the initial cursor position, queue initial command. */ + file_cinit(sp); + + /* Redraw the screen from scratch, schedule a welcome message. */ + F_SET(sp, SC_SCR_REFORMAT | SC_STATUS); + + return (0); + +err: if (frp->name != NULL) { + free(frp->name); + frp->name = NULL; + } + if (frp->tname != NULL) { + (void)unlink(frp->tname); + free(frp->tname); + frp->tname = NULL; + } + +oerr: if (F_ISSET(ep, F_RCV_ON)) + (void)unlink(ep->rcv_path); + if (ep->rcv_path != NULL) { + free(ep->rcv_path); + ep->rcv_path = NULL; + } + if (ep->db != NULL) + (void)ep->db->close(ep->db); + free(ep); + + return (open_err ? + file_init(sp, frp, rcv_name, flags | FS_OPENERR) : 1); +} + +/* + * file_spath -- + * Scan the user's path to find the file that we're going to + * try and open. + */ +static int +file_spath(sp, frp, sbp, existsp) + SCR *sp; + FREF *frp; + struct stat *sbp; + int *existsp; +{ + CHAR_T savech; + size_t len; + int found; + char *name, *p, *t, path[MAXPATHLEN]; + + /* + * 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 . */ + if (!stat(name, sbp)) { + *existsp = 1; + 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) { + savech = *p; + *p = '\0'; + len = snprintf(path, + sizeof(path), "%s/%s", t, name); + *p = savech; + 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) { + MALLOC_RET(sp, p, char *, len + 1); + memcpy(p, path, len + 1); + free(frp->name); + frp->name = p; + } + *existsp = found; + return (0); +} + +/* + * file_cinit -- + * Set up the initial cursor position. + */ +static void +file_cinit(sp) + SCR *sp; +{ + GS *gp; + MARK m; + size_t len; + int nb; + + /* 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; + } + if (ex_run_str(sp, + "-c option", gp->c_option, strlen(gp->c_option), 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(sp, ep, force) + 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; + 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)) { + CIRCLEQ_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 && ep->db->close(ep->db) && !force) { + msgq_str(sp, M_SYSERR, frp->name, "241|%s: close"); + ++ep->refcnt; + return (1); + } + + /* COMMITTED TO THE CLOSE. THERE'S NO GOING BACK... */ + + /* Stop logging. */ + (void)log_end(sp, ep); + + /* Free up any marks. */ + (void)mark_end(sp, ep); + + /* + * 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"); + } + if (ep->fcntl_fd != -1) + (void)close(ep->fcntl_fd); + if (ep->rcv_fd != -1) + (void)close(ep->rcv_fd); + if (ep->rcv_path != NULL) + free(ep->rcv_path); + 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(sp, fm, tm, name, flags) + SCR *sp; + MARK *fm, *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); + + /* Open the file. */ + SIGBLOCK; + if ((fd = open(name, oflags, + S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)) < 0) { + msgq_str(sp, M_SYSERR, name, "%s"); + SIGUNBLOCK; + return (1); + } + SIGUNBLOCK; + + /* 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, 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; + } + + rval = ex_writefp(sp, name, fp, fm, tm, &nlno, &nch, 0); + + /* + * 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); + } + + p = msg_print(sp, name, &nf); + switch (mtype) { + case NEWFILE: + msgstr = msg_cat(sp, + "256|%s: new file: %lu lines, %lu characters", NULL); + len = snprintf(buf, sizeof(buf), msgstr, p, nlno, nch); + break; + case OLDFILE: + msgstr = msg_cat(sp, LF_ISSET(FS_APPEND) ? + "315|%s: appended: %lu lines, %lu characters" : + "257|%s: %lu lines, %lu characters", NULL); + len = snprintf(buf, sizeof(buf), msgstr, p, nlno, nch); + break; + default: + abort(); + } + + /* + * 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); + 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(sp, name, bname) + SCR *sp; + char *name, *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, *estr, *p, *pct, *slash, *t, *wfname, buf[8192]; + + rfd = wfd = -1; + bp = estr = wfname = 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. + */ + argv_init(sp, &cmd); + ex_cinit(&cmd, 0, 0, 0, 0, 0, NULL); + if (bname[0] == 'N') { + version = 1; + ++bname; + } else + version = 0; + if (argv_exp2(sp, &cmd, bname, strlen(bname))) + 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_GOTO(sp, bp, blen, cmd.argv[0]->len * 2 + 50); + for (t = bp, slash = NULL, + p = cmd.argv[0]->bp; 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'; + + if (slash == NULL) { + dirp = opendir("."); + p = bp; + } else { + *slash = '\0'; + dirp = opendir(bp); + *slash = '/'; + p = slash + 1; + } + if (dirp == NULL) { + estr = cmd.argv[0]->bp; + goto err; + } + + for (maxnum = 0; (dp = readdir(dirp)) != NULL;) + if (sscanf(dp->d_name, p, &num) == 1 && num > maxnum) + maxnum = num; + (void)closedir(dirp); + + /* Format the backup file name. */ + (void)snprintf(pct, blen - (pct - bp), "%d", maxnum + 1); + wfname = bp; + } else { + bp = NULL; + wfname = cmd.argv[0]->bp; + } + + /* Open the backup file, avoiding lurkers. */ + if (stat(wfname, &sb) == 0) { + if (!S_ISREG(sb.st_mode)) { + msgq_str(sp, M_ERR, bname, + "259|%s: not a regular file"); + goto err; + } + if (sb.st_uid != getuid()) { + msgq_str(sp, M_ERR, bname, "260|%s: not owned by you"); + goto err; + } + if (sb.st_mode & (S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)) { + msgq_str(sp, M_ERR, bname, + "261|%s: accessible by a user other than the owner"); + goto err; + } + flags = O_TRUNC; + } else + flags = O_CREAT | O_EXCL; + if ((wfd = open(wfname, flags | O_WRONLY, S_IRUSR | S_IWUSR)) < 0) { + estr = bname; + goto err; + } + + /* Copy the file's current contents to its backup value. */ + while ((nr = read(rfd, buf, sizeof(buf))) > 0) + for (off = 0; nr != 0; nr -= nw, off += nw) + if ((nw = write(wfd, buf + off, nr)) < 0) { + estr = wfname; + goto err; + } + if (nr < 0) { + estr = name; + goto err; + } + + if (close(rfd)) { + estr = name; + goto err; + } + if (close(wfd)) { + estr = wfname; + goto err; + } + if (bp != NULL) + FREE_SPACE(sp, bp, blen); + return (0); + +alloc_err: +err: if (rfd != -1) + (void)close(rfd); + if (wfd != -1) { + (void)unlink(wfname); + (void)close(wfd); + } + if (estr) + msgq_str(sp, M_SYSERR, estr, "%s"); + if (bp != NULL) + FREE_SPACE(sp, bp, blen); + return (1); +} + +/* + * file_comment -- + * Skip the first comment. + */ +static void +file_comment(sp) + SCR *sp; +{ + recno_t lno; + size_t len; + char *p; + + 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); + p += 2; + len -= 2; + do { + for (; len > 1; --len, ++p) + if (p[0] == '/' && p[1] == '/') { + sp->lno = lno; + return; + } + } while (!db_get(sp, ++lno, 0, &p, &len)); + } +} + +/* + * 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(sp, force, flags) + SCR *sp; + int force, 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(sp, force) + 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(sp, force) + 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(sp, flags) + 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 *, char *)); + */ +void +set_alt_name(sp, name) + SCR *sp; + 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. + * + * 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(sp, name, fdp, fd, iswrite) + SCR *sp; + char *name; + int *fdp, fd, iswrite; +{ + 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; + + arg.l_type = F_WRLCK; + arg.l_whence = 0; /* SEEK_SET */ + arg.l_start = arg.l_len = 0; + arg.l_pid = 0; + + /* + * 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 +} |
