/*      $OpenBSD: file.c,v 1.105 2026/03/03 15:17:29 op Exp $   */

/* This file is in the public domain. */

/*
 *      File commands.
 */

#include <sys/queue.h>
#include <sys/stat.h>
#include <errno.h>
#include <libgen.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "def.h"

size_t xdirname(char *, const char *, size_t);

/*
 * Insert a file into the current buffer.  Real easy - just call the
 * insertfile routine with the file name.
 */
int
fileinsert(int f, int n)
{
        char     fname[NFILEN], *bufp, *adjf;

        if (getbufcwd(fname, sizeof(fname)) != TRUE)
                fname[0] = '\0';
        bufp = eread("Insert file: ", fname, NFILEN,
            EFNEW | EFCR | EFFILE | EFDEF);
        if (bufp == NULL)
                return (ABORT);
        else if (bufp[0] == '\0')
                return (FALSE);
        adjf = adjustname(bufp, TRUE);
        if (adjf == NULL)
                return (FALSE);
        return (insertfile(adjf, NULL, FALSE));
}

/*
 * Select a file for editing.  If the file is a directory, invoke dired.
 * Otherwise, look around to see if you can find the file in another buffer;
 * if you can find it, just switch to the buffer.  If you cannot find the
 * file, create a new buffer, read in the text, and switch to the new buffer.
 */
int
filevisit(int f, int n)
{
        struct buffer   *bp;
        char     fname[NFILEN], *bufp, *adjf;
        int      status;

        if (getbufcwd(fname, sizeof(fname)) != TRUE)
                fname[0] = '\0';
        bufp = eread("Find file: ", fname, NFILEN,
            EFNEW | EFCR | EFFILE | EFDEF);
        if (bufp == NULL)
                return (ABORT);
        else if (bufp[0] == '\0')
                return (FALSE);
        adjf = adjustname(fname, TRUE);
        if (adjf == NULL)
                return (FALSE);
        if (fisdir(adjf) == TRUE)
                return (do_dired(adjf));
        if ((bp = findbuffer(adjf)) == NULL)
                return (FALSE);
        curbp = bp;
        if (showbuffer(bp, curwp, WFFULL) != TRUE)
                return (FALSE);
        if (bp->b_fname[0] == '\0') {
                if ((status = readin(adjf)) != TRUE)
                        killbuffer(bp);
                return (status);
        }
        return (TRUE);
}

/*
 * Replace the current file with an alternate one. Semantics for finding
 * the replacement file are the same as 'filevisit', except the current
 * buffer is killed before the switch. If the kill fails, or is aborted,
 * revert to the original file.
 */
int
filevisitalt(int f, int n)
{
        char     fname[NFILEN], *bufp;

        if (getbufcwd(fname, sizeof(fname)) != TRUE)
                fname[0] = '\0';
        bufp = eread("Find alternate file: ", fname, NFILEN,
            EFNEW | EFCR | EFFILE | EFDEF);
        if (bufp == NULL)
                return (ABORT);
        else if (bufp[0] == '\0')
                return (FALSE);

        return (do_filevisitalt(fname));
}

int
do_filevisitalt(char *fn)
{
        struct buffer   *bp;
        int              status;
        char            *adjf;

        status = killbuffer(curbp);
        if (status == ABORT || status == FALSE)
                return (ABORT);

        adjf = adjustname(fn, TRUE);
        if (adjf == NULL)
                return (FALSE);
        if (fisdir(adjf) == TRUE)
                return (do_dired(adjf));
        if ((bp = findbuffer(adjf)) == NULL)
                return (FALSE);
        curbp = bp;
        if (showbuffer(bp, curwp, WFFULL) != TRUE)
                return (FALSE);
        if (bp->b_fname[0] == '\0') {
                if ((status = readin(adjf)) != TRUE)
                        killbuffer(bp);
                return (status);
        }
        return (TRUE);
}

int
filevisitro(int f, int n)
{
        int error;

        error = filevisit(f, n);
        if (error != TRUE)
                return (error);
        curbp->b_flag |= BFREADONLY;
        return (TRUE);
}

/*
 * Pop to a file in the other window.  Same as the last function, but uses
 * popbuf instead of showbuffer.
 */
int
poptofile(int f, int n)
{
        struct buffer   *bp;
        struct mgwin    *wp;
        char     fname[NFILEN], *adjf, *bufp;
        int      status;

        if (getbufcwd(fname, sizeof(fname)) != TRUE)
                fname[0] = '\0';
        if ((bufp = eread("Find file in other window: ", fname, NFILEN,
            EFNEW | EFCR | EFFILE | EFDEF)) == NULL)
                return (ABORT);
        else if (bufp[0] == '\0')
                return (FALSE);
        adjf = adjustname(fname, TRUE);
        if (adjf == NULL)
                return (FALSE);
        if (fisdir(adjf) == TRUE)
                return (do_dired(adjf));
        if ((bp = findbuffer(adjf)) == NULL)
                return (FALSE);
        if (bp == curbp)
                return (splitwind(f, n));
        if ((wp = popbuf(bp, WNONE)) == NULL)
                return (FALSE);
        curbp = bp;
        curwp = wp;
        if (bp->b_fname[0] == '\0') {
                if ((status = readin(adjf)) != TRUE)
                        killbuffer(bp);
                return (status);
        }
        return (TRUE);
}

/*
 * Read the file "fname" into the current buffer.  Make all of the text
 * in the buffer go away, after checking for unsaved changes.  This is
 * called by the "read" command, the "visit" command, and the mainline
 * (for "mg file").
 */
int
readin(char *fname)
{
        struct mgwin    *wp;
        struct stat      statbuf;
        int      status, i, ro = FALSE;
        PF      *ael;
        char     dp[NFILEN];

        /* might be old */
        if (bclear(curbp) != TRUE)
                return (TRUE);
        /* Clear readonly. May be set by autoexec path */
        curbp->b_flag &= ~BFREADONLY;
        if ((status = insertfile(fname, fname, TRUE)) != TRUE) {
                dobeep();
                ewprintf("File is not readable: %s", fname);
                return (FALSE);
        }

        for (wp = wheadp; wp != NULL; wp = wp->w_wndp) {
                if (wp->w_bufp == curbp) {
                        wp->w_dotp = wp->w_linep = bfirstlp(curbp);
                        wp->w_doto = 0;
                        wp->w_markp = NULL;
                        wp->w_marko = 0;
                }
        }

        /*
         * Call auto-executing function if we need to.
         */
        if ((ael = find_autoexec(fname)) != NULL) {
                for (i = 0; ael[i] != NULL; i++)
                        (*ael[i])(0, 1);
                free(ael);
        }

        /* no change */
        curbp->b_flag &= ~BFCHG;

        /*
         * Set the buffer READONLY flag if any of following are true:
         *   1. file is a directory.
         *   2. file is read-only.
         *   3. file doesn't exist and directory is read-only.
         */
        if (fisdir(fname) == TRUE) {
                ro = TRUE;
        } else if ((access(fname, W_OK) == -1)) {
                if (errno != ENOENT) {
                        ro = TRUE;
                } else if (errno == ENOENT) {
                        (void)xdirname(dp, fname, sizeof(dp));
                        (void)strlcat(dp, "/", sizeof(dp));

                        /* Missing directory; keep buffer rw, like emacs */
                        if (stat(dp, &statbuf) == -1 && errno == ENOENT) {
                                if (eyorn("Missing directory, create") == TRUE)
                                        (void)do_makedir(dp);
                        } else if (access(dp, W_OK) == -1 && errno == EACCES) {
                                ewprintf("File not found and directory"
                                    " write-protected");
                                ro = TRUE;
                        }
                }
        }
        if (ro == TRUE)
                curbp->b_flag |= BFREADONLY;

        if (startrow) {
                gotoline(FFARG, startrow);
                startrow = 0;
        }

        undo_add_modified();
        return (status);
}

/*
 * NB, getting file attributes is done here under control of a flag
 * rather than in readin, which would be cleaner.  I was concerned
 * that some operating system might require the file to be open
 * in order to get the information.  Similarly for writing.
 */

/*
 * Insert a file in the current buffer, after dot. If file is a directory,
 * and 'replacebuf' is TRUE, invoke dired mode, else die with an error.
 * If file is a regular file, set mark at the end of the text inserted;
 * point at the beginning.  Return a standard status. Print a summary
 * (lines read, error message) out as well. This routine also does the
 * read end of backup processing.  The BFBAK flag, if set in a buffer,
 * says that a backup should be taken.  It is set when a file is read in,
 * but not on a new file. You don't need to make a backup copy of nothing.
 */

static char     *line = NULL;
static int      linesize = 0;

int
insertfile(char *fname, char *newname, int replacebuf)
{
        struct buffer   *bp;
        struct line     *lp1, *lp2;
        struct line     *olp;                   /* line we started at */
        struct mgwin    *wp;
        int      nbytes, s, nline = 0, siz, x, x2;
        int      opos;                  /* offset we started at */
        int      oline;                 /* original line number */
        FILE    *ffp;

        if (replacebuf == TRUE)
                x = undo_enable(FFRAND, 0);
        else
                x = undo_enabled();

        lp1 = NULL;
        if (line == NULL) {
                line = malloc(NLINE);
                if (line == NULL)
                        panic("out of memory");
                linesize = NLINE;
        }

        /* cheap */
        bp = curbp;
        if (newname != NULL) {
                (void)strlcpy(bp->b_fname, newname, sizeof(bp->b_fname));
                (void)xdirname(bp->b_cwd, newname, sizeof(bp->b_cwd));
                (void)strlcat(bp->b_cwd, "/", sizeof(bp->b_cwd));
        }

        /* hard file open */
        if ((s = ffropen(&ffp, fname, (replacebuf == TRUE) ? bp : NULL))
            == FIOERR)
                goto out;
        if (s == FIOFNF) {
                /* file not found */
                if (newname != NULL)
                        ewprintf("(New file)");
                else
                        ewprintf("(File not found)");
                goto out;
        } else if (s == FIODIR) {
                /* file was a directory */
                if (replacebuf == FALSE) {
                        dobeep();
                        ewprintf("Cannot insert: file is a directory, %s",
                            fname);
                        goto cleanup;
                }
                killbuffer(bp);
                bp = dired_(fname);
                undo_enable(FFRAND, x);
                if (bp == NULL)
                        return (FALSE);
                curbp = bp;
                return (showbuffer(bp, curwp, WFFULL | WFMODE));
        } else {
                (void)xdirname(bp->b_cwd, fname, sizeof(bp->b_cwd));
                (void)strlcat(bp->b_cwd, "/", sizeof(bp->b_cwd));
        }
        opos = curwp->w_doto;
        oline = curwp->w_dotline;
        /*
         * Open a new line at dot and start inserting after it.
         * We will delete this newline after insertion.
         * Disable undo, as we create the undo record manually.
         */
        x2 = undo_enable(FFRAND, 0);
        (void)lnewline();
        olp = lback(curwp->w_dotp);
        undo_enable(FFRAND, x2);

        nline = 0;
        siz = 0;
        while ((s = ffgetline(ffp, line, linesize, &nbytes)) != FIOERR) {
retry:
                siz += nbytes + 1;
                switch (s) {
                case FIOSUC:
                        /* FALLTHRU */
                case FIOEOF:
                        ++nline;
                        if ((lp1 = lalloc(nbytes)) == NULL) {
                                /* keep message on the display */
                                s = FIOERR;
                                undo_add_insert(olp, opos,
                                    siz - nbytes - 1 - 1);
                                goto endoffile;
                        }
                        bcopy(line, &ltext(lp1)[0], nbytes);
                        lp2 = lback(curwp->w_dotp);
                        lp2->l_fp = lp1;
                        lp1->l_fp = curwp->w_dotp;
                        lp1->l_bp = lp2;
                        curwp->w_dotp->l_bp = lp1;
                        if (s == FIOEOF) {
                                undo_add_insert(olp, opos, siz - 1);
                                goto endoffile;
                        }
                        break;
                case FIOLONG: {
                                /* a line too long to fit in our buffer */
                                char    *cp;
                                int     newsize;

                                newsize = linesize * 2;
                                if (newsize < 0 ||
                                    (cp = malloc(newsize)) == NULL) {
                                        dobeep();
                                        ewprintf("Could not allocate %d bytes",
                                            newsize);
                                        s = FIOERR;
                                        goto endoffile;
                                }
                                bcopy(line, cp, linesize);
                                free(line);
                                line = cp;
                                s = ffgetline(ffp, line + linesize, linesize,
                                    &nbytes);
                                nbytes += linesize;
                                linesize = newsize;
                                if (s == FIOERR)
                                        goto endoffile;
                                goto retry;
                        }
                default:
                        dobeep();
                        ewprintf("Unknown code %d reading file", s);
                        s = FIOERR;
                        break;
                }
        }
endoffile:
        /* ignore errors */
        (void)ffclose(ffp, NULL);
        /* don't zap an error */
        if (s == FIOEOF) {
                if (nline == 1)
                        ewprintf("(Read 1 line)");
                else
                        ewprintf("(Read %d lines)", nline);
        }
        /* set mark at the end of the text */
        curwp->w_dotp = curwp->w_markp = lback(curwp->w_dotp);
        curwp->w_marko = llength(curwp->w_markp);
        curwp->w_markline = oline + nline + 1;
        /*
         * if we are at the end of the file, ldelnewline is a no-op,
         * but we still need to decrement the line and markline counts
         * as we've accounted for this fencepost in our arithmetic
         */
        if (lforw(curwp->w_dotp) == curwp->w_bufp->b_headp) {
                curwp->w_bufp->b_lines--;
                curwp->w_markline--;
        } else
                (void)ldelnewline();
        curwp->w_dotp = olp;
        curwp->w_doto = opos;
        curwp->w_dotline = oline;
        if (olp == curbp->b_headp)
                curwp->w_dotp = lforw(olp);
        if (newname != NULL)
                bp->b_flag |= BFCHG | BFBAK;    /* Need a backup.        */
        else
                bp->b_flag |= BFCHG;
        /*
         * If the insert was at the end of buffer, set lp1 to the end of
         * buffer line, and lp2 to the beginning of the newly inserted text.
         * (Otherwise lp2 is set to NULL.)  This is used below to set
         * pointers in other windows correctly if they are also at the end of
         * buffer.
         */
        lp1 = bp->b_headp;
        if (curwp->w_markp == lp1) {
                lp2 = curwp->w_dotp;
        } else {
                /* delete extraneous newline */
                (void)ldelnewline();
out:            lp2 = NULL;
        }
        for (wp = wheadp; wp != NULL; wp = wp->w_wndp) {
                if (wp->w_bufp == curbp) {
                        wp->w_rflag |= WFMODE | WFEDIT;
                        if (wp != curwp && lp2 != NULL) {
                                if (wp->w_dotp == lp1)
                                        wp->w_dotp = lp2;
                                if (wp->w_markp == lp1)
                                        wp->w_markp = lp2;
                                if (wp->w_linep == lp1)
                                        wp->w_linep = lp2;
                        }
                }
        }
        bp->b_lines += nline;
cleanup:
        undo_enable(FFRAND, x);

        /* return FALSE if error */
        return (s != FIOERR);
}

/*
 * Ask for a file name and write the contents of the current buffer to that
 * file.  Update the remembered file name and clear the buffer changed flag.
 * This handling of file names is different from the earlier versions and
 * is more compatible with Gosling EMACS than with ITS EMACS.
 */
int
filewrite(int f, int n)
{
        struct stat     statbuf;
        int      s;
        char     fname[NFILEN], bn[NBUFN], tmp[NFILEN + 25];
        char    *adjfname, *bufp;
        FILE    *ffp;

        if (getbufcwd(fname, sizeof(fname)) != TRUE)
                fname[0] = '\0';
        if ((bufp = eread("Write file: ", fname, NFILEN,
            EFDEF | EFNEW | EFCR | EFFILE)) == NULL)
                return (ABORT);
        else if (bufp[0] == '\0')
                return (FALSE);

        adjfname = adjustname(fname, TRUE);
        if (adjfname == NULL)
                return (FALSE);

        /* Check if file exists; write checks done later */
        if (stat(adjfname, &statbuf) == 0) {
                if (S_ISDIR(statbuf.st_mode)) {
                        dobeep();
                        ewprintf("%s is a directory", adjfname);
                        return (FALSE);
                }
                snprintf(tmp, sizeof(tmp), "File `%s' exists; overwrite",
                    adjfname);
                if ((s = eyorn(tmp)) != TRUE)
                        return (s);
        }

        /* old attributes are no longer current */
        bzero(&curbp->b_fi, sizeof(curbp->b_fi));
        if ((s = writeout(&ffp, curbp, adjfname)) == TRUE) {
                (void)strlcpy(curbp->b_fname, adjfname, sizeof(curbp->b_fname));
                if (getbufcwd(curbp->b_cwd, sizeof(curbp->b_cwd)) != TRUE)
                        (void)strlcpy(curbp->b_cwd, "/", sizeof(curbp->b_cwd));
                if (augbname(bn, curbp->b_fname, sizeof(bn))
                    == FALSE)
                        return (FALSE);
                free(curbp->b_bname);
                if ((curbp->b_bname = strdup(bn)) == NULL)
                        return (FALSE);
                (void)fupdstat(curbp);
                curbp->b_flag &= ~(BFBAK | BFCHG);
                upmodes(curbp);
                undo_add_boundary(FFRAND, 1);
                undo_add_modified();
        }
        return (s);
}

/*
 * Save the contents of the current buffer back into its associated file.
 */
static int      makebackup = TRUE;

int
filesave(int f, int n)
{
        if ((curbp->b_flag & BFCHG) == 0) {
                ewprintf("(No changes need to be saved)");
                return (TRUE);
        }

        if (curbp->b_fname[0] == '\0')
                return (filewrite(f, n));
        else
                return (buffsave(curbp));
}

/*
 * Save the contents of the buffer argument into its associated file.
 * Error if there is no remembered file name. If this is the first write
 * since the read or visit, then a backup copy of the file is made.
 * Allow user to select whether or not to make backup files by looking at
 * the value of makebackup.
 */
int
buffsave(struct buffer *bp)
{
        int      s;
        FILE    *ffp;

        /* must have a name */
        if (bp->b_fname[0] == '\0') {
                dobeep();
                ewprintf("No file name");
                return (FALSE);
        }

        /* Ensure file has not been modified elsewhere */
        /* We don't use the ignore flag here */
        if (fchecktime(bp) != TRUE) {
                if ((s = eyesno("File has changed on disk since last save. "
                    "Save anyway")) != TRUE)
                        return (s);
        }
        
        if (makebackup && (bp->b_flag & BFBAK)) {
                s = fbackupfile(bp->b_fname);
                /* hard error */
                if (s == ABORT)
                        return (FALSE);
                /* softer error */
                if (s == FALSE &&
                    (s = eyesno("Backup error, save anyway")) != TRUE)
                        return (s);
        }
        if ((s = writeout(&ffp, bp, bp->b_fname)) == TRUE) {
                (void)fupdstat(bp);
                bp->b_flag &= ~(BFCHG | BFBAK);
                upmodes(bp);
                undo_add_boundary(FFRAND, 1);
                undo_add_modified();
        }
        return (s);
}

/*
 * Since we don't have variables (we probably should) this is a command
 * processor for changing the value of the make backup flag.  If no argument
 * is given, sets makebackup to true, so backups are made.  If an argument is
 * given, no backup files are made when saving a new version of a file.
 */
int
makebkfile(int f, int n)
{
        if (f & FFARG)
                makebackup = n > 0;
        else
                makebackup = !makebackup;
        ewprintf("Backup files %sabled", makebackup ? "en" : "dis");
        return (TRUE);
}

/*
 * NB: bp is passed to both ffwopen and ffclose because some
 * attribute information may need to be updated at open time
 * and others after the close.  This is OS-dependent.  Note
 * that the ff routines are assumed to be able to tell whether
 * the attribute information has been set up in this buffer
 * or not.
 */

/*
 * This function performs the details of file writing; writing the file
 * in buffer bp to file fn. Uses the file management routines in the
 * "fileio.c" package. Most of the grief is checking of some sort.
 * You may want to call fupdstat() after using this function.
 */
int
writeout(FILE ** ffp, struct buffer *bp, char *fn)
{
        struct stat      statbuf;
        struct line     *lpend;
        int              s, eobnl;
        char             dp[NFILEN];

        if (stat(fn, &statbuf) == -1 && errno == ENOENT) {
                errno = 0;
                (void)xdirname(dp, fn, sizeof(dp));
                (void)strlcat(dp, "/", sizeof(dp));
                if (access(dp, W_OK) && errno == EACCES) {
                        dobeep();
                        ewprintf("Directory %s write-protected", dp);
                        return (FIOERR);
                } else if (errno == ENOENT) {
                        dobeep();
                        ewprintf("%s: no such directory", dp);
                        return (FIOERR);
                }
        }
        lpend = bp->b_headp;
        eobnl = 0;
        if (llength(lback(lpend)) != 0) {
                eobnl = eyorn("No newline at end of file, add one");
                if (eobnl != TRUE && eobnl != FALSE)
                        return (eobnl); /* abort */
        }
        /* open writes message */
        if ((s = ffwopen(ffp, fn, bp)) != FIOSUC)
                return (FALSE);
        s = ffputbuf(*ffp, bp, eobnl);
        if (s == FIOSUC) {
                /* no write error */
                s = ffclose(*ffp, bp);
                if (s == FIOSUC)
                        ewprintf("Wrote %s", fn);
        } else {
                /* print a message indicating write error */
                (void)ffclose(*ffp, bp);
                dobeep();
                ewprintf("Unable to write %s", fn);
        }
        return (s == FIOSUC);
}

/*
 * Tag all windows for bp (all windows if bp == NULL) as needing their
 * mode line updated.
 */
void
upmodes(struct buffer *bp)
{
        struct mgwin    *wp;

        for (wp = wheadp; wp != NULL; wp = wp->w_wndp)
                if (bp == NULL || curwp->w_bufp == bp)
                        wp->w_rflag |= WFMODE;
}

/*
 * dirname using strlcpy semantic.
 * Like dirname() except an empty string is returned in
 * place of "/". This means we can always add a trailing
 * slash and be correct.
 * Address portability issues by copying argument
 * before using. Some implementations modify the input string.
 */
size_t
xdirname(char *dp, const char *path, size_t dplen)
{
        char ts[NFILEN];
        size_t len;

        (void)strlcpy(ts, path, NFILEN);
        len = strlcpy(dp, dirname(ts), dplen);
        if (dplen > 0 && dp[0] == '/' && dp[1] == '\0') {
                dp[0] = '\0';
                len = 0;
        }
        return (len);
}

/*
 * basename using strlcpy/strlcat semantic.
 * Address portability issue by copying argument
 * before using: some implementations modify the input string.
 */
size_t
xbasename(char *bp, const char *path, size_t bplen)
{
        char ts[NFILEN];

        (void)strlcpy(ts, path, NFILEN);
        return (strlcpy(bp, basename(ts), bplen));
}

/*
 * The adjusted file name refers to a directory, so open dired mode.
 */
int
do_dired(char *adjf)
{
        struct buffer   *bp;

        if ((bp = dired_(adjf)) == FALSE)
                return (FALSE);
        curbp = bp;
        return (showbuffer(bp, curwp, WFFULL | WFMODE));
}