Page MenuHomeFreeBSD
Differential D34411 Diff 103491 contrib/mg/fileio.c

Changeset View

Standalone View

View Options

contrib/mg/fileio.c

  • This file was added.
/* $OpenBSD: fileio.c,v 1.108 2021/03/01 10:51:14 lum Exp $ */
/* This file is in the public domain. */
/*
* POSIX fileio.c
*/
#include <sys/queue.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "def.h"
#include "kbd.h"
#include "pathnames.h"
static char *bkuplocation(const char *);
static int bkupleavetmp(const char *);
static char *bkupdir;
static int leavetmp = 0; /* 1 = leave any '~' files in tmp dir */
/*
* Open a file for reading.
*/
int
ffropen(FILE ** ffp, const char *fn, struct buffer *bp)
{
if ((*ffp = fopen(fn, "r")) == NULL) {
if (errno == ENOENT)
return (FIOFNF);
return (FIOERR);
}
/* If 'fn' is a directory open it with dired. */
if (fisdir(fn) == TRUE)
return (FIODIR);
ffstat(*ffp, bp);
return (FIOSUC);
}
/*
* Update stat/dirty info
*/
void
ffstat(FILE *ffp, struct buffer *bp)
{
struct stat sb;
if (bp && fstat(fileno(ffp), &sb) == 0) {
/* set highorder bit to make sure this isn't all zero */
bp->b_fi.fi_mode = sb.st_mode | 0x8000;
bp->b_fi.fi_uid = sb.st_uid;
bp->b_fi.fi_gid = sb.st_gid;
bp->b_fi.fi_mtime = sb.st_mtimespec;
/* Clear the ignore flag */
bp->b_flag &= ~(BFIGNDIRTY | BFDIRTY);
}
}
/*
* Update the status/dirty info. If there is an error,
* there's not a lot we can do.
*/
int
fupdstat(struct buffer *bp)
{
FILE *ffp;
if ((ffp = fopen(bp->b_fname, "r")) == NULL) {
if (errno == ENOENT)
return (FIOFNF);
return (FIOERR);
}
ffstat(ffp, bp);
(void)ffclose(ffp, bp);
return (FIOSUC);
}
/*
* Open a file for writing.
*/
int
ffwopen(FILE ** ffp, const char *fn, struct buffer *bp)
{
int fd;
mode_t fmode = DEFFILEMODE;
if (bp && bp->b_fi.fi_mode)
fmode = bp->b_fi.fi_mode & 07777;
fd = open(fn, O_RDWR | O_CREAT | O_TRUNC, fmode);
if (fd == -1) {
ffp = NULL;
dobeep();
ewprintf("Cannot open file for writing : %s", strerror(errno));
return (FIOERR);
}
if ((*ffp = fdopen(fd, "w")) == NULL) {
dobeep();
ewprintf("Cannot open file for writing : %s", strerror(errno));
close(fd);
return (FIOERR);
}
/*
* If we have file information, use it. We don't bother to check for
* errors, because there's no a lot we can do about it. Certainly
* trying to change ownership will fail if we aren't root. That's
* probably OK. If we don't have info, no need to get it, since any
* future writes will do the same thing.
*/
if (bp && bp->b_fi.fi_mode) {
fchmod(fd, bp->b_fi.fi_mode & 07777);
fchown(fd, bp->b_fi.fi_uid, bp->b_fi.fi_gid);
}
return (FIOSUC);
}
/*
* Close a file.
*/
/* ARGSUSED */
int
ffclose(FILE *ffp, struct buffer *bp)
{
if (fclose(ffp) == 0)
return (FIOSUC);
return (FIOERR);
}
/*
* Write a buffer to the already opened file. bp points to the
* buffer. Return the status.
*/
int
ffputbuf(FILE *ffp, struct buffer *bp, int eobnl)
{
struct line *lp, *lpend;
lpend = bp->b_headp;
for (lp = lforw(lpend); lp != lpend; lp = lforw(lp)) {
if (fwrite(ltext(lp), 1, llength(lp), ffp) != llength(lp)) {
dobeep();
ewprintf("Write I/O error");
return (FIOERR);
}
if (lforw(lp) != lpend) /* no implied \n on last line */
putc(*bp->b_nlchr, ffp);
}
if (eobnl) {
lnewline_at(lback(lpend), llength(lback(lpend)));
putc(*bp->b_nlchr, ffp);
}
return (FIOSUC);
}
/*
* Read a line from a file, and store the bytes
* in the supplied buffer. Stop on end of file or end of
* line. When FIOEOF is returned, there is a valid line
* of data without the normally implied \n.
* If the line length exceeds nbuf, FIOLONG is returned.
*/
int
ffgetline(FILE *ffp, char *buf, int nbuf, int *nbytes)
{
int c, i;
i = 0;
while ((c = getc(ffp)) != EOF && c != *curbp->b_nlchr) {
buf[i++] = c;
if (i >= nbuf)
return (FIOLONG);
}
if (c == EOF && ferror(ffp) != FALSE) {
dobeep();
ewprintf("File read error");
return (FIOERR);
}
*nbytes = i;
return (c == EOF ? FIOEOF : FIOSUC);
}
/*
* Make a backup copy of "fname". On Unix the backup has the same
* name as the original file, with a "~" on the end; this seems to
* be newest of the new-speak. The error handling is all in "file.c".
* We do a copy instead of a rename since otherwise another process
* with an open fd will get the backup, not the new file. This is
* a problem when using mg with things like crontab and vipw.
*/
int
fbackupfile(const char *fn)
{
struct stat sb;
struct timespec new_times[2];
int from, to, serrno;
ssize_t nread;
char buf[BUFSIZ];
char *nname, *tname, *bkpth;
if (stat(fn, &sb) == -1) {
dobeep();
ewprintf("Can't stat %s : %s", fn, strerror(errno));
return (FALSE);
}
if ((bkpth = bkuplocation(fn)) == NULL)
return (FALSE);
if (asprintf(&nname, "%s~", bkpth) == -1) {
dobeep();
ewprintf("Can't allocate backup file name : %s", strerror(errno));
free(bkpth);
return (ABORT);
}
if (asprintf(&tname, "%s.XXXXXXXXXX", bkpth) == -1) {
dobeep();
ewprintf("Can't allocate temp file name : %s", strerror(errno));
free(bkpth);
free(nname);
return (ABORT);
}
free(bkpth);
if ((from = open(fn, O_RDONLY)) == -1) {
free(nname);
free(tname);
return (FALSE);
}
to = mkstemp(tname);
if (to == -1) {
serrno = errno;
close(from);
free(nname);
free(tname);
errno = serrno;
return (FALSE);
}
while ((nread = read(from, buf, sizeof(buf))) > 0) {
if (write(to, buf, (size_t)nread) != nread) {
nread = -1;
break;
}
}
serrno = errno;
(void) fchmod(to, (sb.st_mode & 0777));
/* copy the mtime to the backupfile */
new_times[0] = sb.st_atim;
new_times[1] = sb.st_mtim;
futimens(to, new_times);
close(from);
close(to);
if (nread == -1) {
if (unlink(tname) == -1)
ewprintf("Can't unlink temp : %s", strerror(errno));
} else {
if (rename(tname, nname) == -1) {
ewprintf("Can't rename temp : %s", strerror(errno));
(void) unlink(tname);
nread = -1;
}
}
free(nname);
free(tname);
errno = serrno;
return (nread == -1 ? FALSE : TRUE);
}
/*
* Convert "fn" to a canonicalized absolute filename, replacing
* a leading ~/ with the user's home dir, following symlinks, and
* remove all occurrences of /./ and /../
*/
char *
adjustname(const char *fn, int slashslash)
{
static char fnb[PATH_MAX];
const char *cp, *ep = NULL;
char *path;
if (slashslash == TRUE) {
cp = fn + strlen(fn) - 1;
for (; cp >= fn; cp--) {
if (ep && (*cp == '/')) {
fn = ep;
break;
}
if (*cp == '/' || *cp == '~')
ep = cp;
else
ep = NULL;
}
}
if ((path = expandtilde(fn)) == NULL)
return (NULL);
if (realpath(path, fnb) == NULL)
(void)strlcpy(fnb, path, sizeof(fnb));
free(path);
return (fnb);
}
/*
* Find a startup file for the user and return its name. As a service
* to other pieces of code that may want to find a startup file (like
* the terminal driver in particular), accepts a suffix to be appended
* to the startup file name.
*/
char *
startupfile(char *suffix, char *conffile)
{
static char file[NFILEN];
char *home;
int ret;
if ((home = getenv("HOME")) == NULL || *home == '\0')
goto nohome;
if (conffile != NULL) {
(void)strncpy(file, conffile, NFILEN);
} else if (suffix == NULL) {
ret = snprintf(file, sizeof(file), _PATH_MG_STARTUP, home);
if (ret < 0 || ret >= sizeof(file))
return (NULL);
} else {
ret = snprintf(file, sizeof(file), _PATH_MG_TERM, home, suffix);
if (ret < 0 || ret >= sizeof(file))
return (NULL);
}
if (access(file, R_OK) == 0)
return (file);
nohome:
#ifdef STARTUPFILE
if (suffix == NULL) {
ret = snprintf(file, sizeof(file), "%s", STARTUPFILE);
if (ret < 0 || ret >= sizeof(file))
return (NULL);
} else {
ret = snprintf(file, sizeof(file), "%s%s", STARTUPFILE,
suffix);
if (ret < 0 || ret >= sizeof(file))
return (NULL);
}
if (access(file, R_OK) == 0)
return (file);
#endif /* STARTUPFILE */
return (NULL);
}
int
copy(char *frname, char *toname)
{
int ifd, ofd;
char buf[BUFSIZ];
mode_t fmode = DEFFILEMODE; /* XXX?? */
struct stat orig;
ssize_t sr;
if ((ifd = open(frname, O_RDONLY)) == -1)
return (FALSE);
if (fstat(ifd, &orig) == -1) {
dobeep();
ewprintf("fstat: %s", strerror(errno));
close(ifd);
return (FALSE);
}
if ((ofd = open(toname, O_WRONLY|O_CREAT|O_TRUNC, fmode)) == -1) {
close(ifd);
return (FALSE);
}
while ((sr = read(ifd, buf, sizeof(buf))) > 0) {
if (write(ofd, buf, (size_t)sr) != sr) {
ewprintf("write error : %s", strerror(errno));
break;
}
}
if (fchmod(ofd, orig.st_mode) == -1)
ewprintf("Cannot set original mode : %s", strerror(errno));
if (sr == -1) {
ewprintf("Read error : %s", strerror(errno));
close(ifd);
close(ofd);
return (FALSE);
}
/*
* It is "normal" for this to fail since we can't guarantee that
* we will be running as root.
*/
if (fchown(ofd, orig.st_uid, orig.st_gid) && errno != EPERM)
ewprintf("Cannot set owner : %s", strerror(errno));
(void) close(ifd);
(void) close(ofd);
return (TRUE);
}
/*
* return list of file names that match the name in buf.
*/
struct list *
make_file_list(char *buf)
{
char *dir, *file, *cp;
size_t len, preflen;
int ret;
DIR *dirp;
struct dirent *dent;
struct list *last, *current;
char fl_name[NFILEN + 2];
char prefixx[NFILEN + 1];
/*
* We need three different strings:
* dir - the name of the directory containing what the user typed.
* Must be a real unix file name, e.g. no ~user, etc..
* Must not end in /.
* prefix - the portion of what the user typed that is before the
* names we are going to find in the directory. Must have a
* trailing / if the user typed it.
* names from the directory - We open dir, and return prefix
* concatenated with names.
*/
/* first we get a directory name we can look up */
/*
* Names ending in . are potentially odd, because adjustname will
* treat foo/bar/.. as a foo/, whereas we are
* interested in names starting with ..
*/
len = strlen(buf);
if (len && buf[len - 1] == '.') {
buf[len - 1] = 'x';
dir = adjustname(buf, TRUE);
buf[len - 1] = '.';
} else
dir = adjustname(buf, TRUE);
if (dir == NULL)
return (NULL);
/*
* If the user typed a trailing / or the empty string
* he wants us to use his file spec as a directory name.
*/
if (len && buf[len - 1] != '/') {
file = strrchr(dir, '/');
if (file) {
*file = '\0';
if (*dir == '\0')
dir = "/";
} else
return (NULL);
}
/* Now we get the prefix of the name the user typed. */
if (strlcpy(prefixx, buf, sizeof(prefixx)) >= sizeof(prefixx))
return (NULL);
cp = strrchr(prefixx, '/');
if (cp == NULL)
prefixx[0] = '\0';
else
cp[1] = '\0';
preflen = strlen(prefixx);
/* cp is the tail of buf that really needs to be compared. */
cp = buf + preflen;
len = strlen(cp);
/*
* Now make sure that file names will fit in the buffers allocated.
* SV files are fairly short. For BSD, something more general would
* be required.
*/
if (preflen > NFILEN - NAME_MAX)
return (NULL);
/* loop over the specified directory, making up the list of files */
/*
* Note that it is worth our time to filter out names that don't
* match, even though our caller is going to do so again, and to
* avoid doing the stat if completion is being done, because stat'ing
* every file in the directory is relatively expensive.
*/
dirp = opendir(dir);
if (dirp == NULL)
return (NULL);
last = NULL;
while ((dent = readdir(dirp)) != NULL) {
int isdir;
if (strncmp(cp, dent->d_name, len) != 0)
continue;
isdir = 0;
if (dent->d_type == DT_DIR) {
isdir = 1;
} else if (dent->d_type == DT_LNK ||
dent->d_type == DT_UNKNOWN) {
struct stat statbuf;
if (fstatat(dirfd(dirp), dent->d_name, &statbuf, 0) < 0)
continue;
if (S_ISDIR(statbuf.st_mode))
isdir = 1;
}
if ((current = malloc(sizeof(struct list))) == NULL) {
free_file_list(last);
closedir(dirp);
return (NULL);
}
ret = snprintf(fl_name, sizeof(fl_name),
"%s%s%s", prefixx, dent->d_name, isdir ? "/" : "");
if (ret < 0 || ret >= sizeof(fl_name)) {
free(current);
continue;
}
current->l_next = last;
current->l_name = strdup(fl_name);
last = current;
}
closedir(dirp);
return (last);
}
/*
* Test if a supplied filename refers to a directory
* Returns ABORT on error, TRUE if directory. FALSE otherwise
*/
int
fisdir(const char *fname)
{
struct stat statbuf;
if (stat(fname, &statbuf) != 0)
return (ABORT);
if (S_ISDIR(statbuf.st_mode))
return (TRUE);
return (FALSE);
}
/*
* Check the mtime of the supplied filename.
* Return TRUE if last mtime matches, FALSE if not,
* If the stat fails, return TRUE and try the save anyway
*/
int
fchecktime(struct buffer *bp)
{
struct stat sb;
if (stat(bp->b_fname, &sb) == -1)
return (TRUE);
if (bp->b_fi.fi_mtime.tv_sec != sb.st_mtimespec.tv_sec ||
bp->b_fi.fi_mtime.tv_nsec != sb.st_mtimespec.tv_nsec)
return (FALSE);
return (TRUE);
}
/*
* Location of backup file. This function creates the correct path.
*/
static char *
bkuplocation(const char *fn)
{
struct stat sb;
char *ret;
if (bkupdir != NULL && (stat(bkupdir, &sb) == 0) &&
S_ISDIR(sb.st_mode) && !bkupleavetmp(fn)) {
char fname[NFILEN];
const char *c;
int i = 0, len;
c = fn;
len = strlen(bkupdir);
while (*c != '\0') {
/* Make sure we don't go over combined:
* strlen(bkupdir + '/' + fname + '\0')
*/
if (i >= NFILEN - len - 1)
return (NULL);
if (*c == '/') {
fname[i] = '!';
} else if (*c == '!') {
if (i >= NFILEN - len - 2)
return (NULL);
fname[i++] = '!';
fname[i] = '!';
} else
fname[i] = *c;
i++;
c++;
}
fname[i] = '\0';
if (asprintf(&ret, "%s/%s", bkupdir, fname) == -1)
return (NULL);
} else if ((ret = strndup(fn, NFILEN)) == NULL)
return (NULL);
return (ret);
}
int
backuptohomedir(int f, int n)
{
const char *c = _PATH_MG_DIR;
char *p;
if (bkupdir == NULL) {
p = adjustname(c, TRUE);
bkupdir = strndup(p, NFILEN);
if (bkupdir == NULL)
return(FALSE);
if (mkdir(bkupdir, 0700) == -1 && errno != EEXIST) {
free(bkupdir);
bkupdir = NULL;
}
} else {
free(bkupdir);
bkupdir = NULL;
}
return (TRUE);
}
/*
* For applications that use mg as the editor and have a desire to keep
* '~' files in /tmp, toggle the location: /tmp | ~/.mg.d
*/
int
toggleleavetmp(int f, int n)
{
leavetmp = !leavetmp;
return (TRUE);
}
/*
* Returns TRUE if fn is located in the temp directory and we want to save
* those backups there.
*/
int
bkupleavetmp(const char *fn)
{
if (!leavetmp)
return(FALSE);
if (strncmp(fn, "/tmp", 4) == 0)
return (TRUE);
return (FALSE);
}
/*
* Expand file names beginning with '~' if appropriate:
* 1, if ./~fn exists, continue without expanding tilde.
* 2, else, if username 'fn' exists, expand tilde with home directory path.
* 3, otherwise, continue and create new buffer called ~fn.
*/
char *
expandtilde(const char *fn)
{
struct passwd *pw;
struct stat statbuf;
const char *cp;
char user[LOGIN_NAME_MAX], path[NFILEN];
char *ret;
size_t ulen, plen;
path[0] = '\0';
if (fn[0] != '~' || stat(fn, &statbuf) == 0) {
if ((ret = strndup(fn, NFILEN)) == NULL)
return (NULL);
return(ret);
}
cp = strchr(fn, '/');
if (cp == NULL)
cp = fn + strlen(fn); /* point to the NUL byte */
ulen = cp - &fn[1];
if (ulen >= sizeof(user)) {
if ((ret = strndup(fn, NFILEN)) == NULL)
return (NULL);
return(ret);
}
if (ulen == 0) /* ~/ or ~ */
pw = getpwuid(geteuid());
else { /* ~user/ or ~user */
memcpy(user, &fn[1], ulen);
user[ulen] = '\0';
pw = getpwnam(user);
}
if (pw != NULL) {
plen = strlcpy(path, pw->pw_dir, sizeof(path));
if (plen == 0 || path[plen - 1] != '/') {
if (strlcat(path, "/", sizeof(path)) >= sizeof(path)) {
dobeep();
ewprintf("Path too long");
return (NULL);
}
}
fn = cp;
if (*fn == '/')
fn++;
}
if (strlcat(path, fn, sizeof(path)) >= sizeof(path)) {
dobeep();
ewprintf("Path too long");
return (NULL);
}
if ((ret = strndup(path, NFILEN)) == NULL)
return (NULL);
return (ret);
}