/* $NetBSD: dir.c,v 1.35 2020/08/09 00:34:21 dholland Exp $ */
/*-
* Copyright (c) 1980, 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)dir.c 8.1 (Berkeley) 5/31/93";
#else
__RCSID("$NetBSD: dir.c,v 1.35 2020/08/09 00:34:21 dholland Exp $");
#endif
#endif /* not lint */
#include <sys/param.h>
#include <sys/stat.h>
#include <errno.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "csh.h"
#include "dir.h"
#include "extern.h"
/* Directory management. */
static struct directory *dfind(Char *);
static Char *dfollow(Char *);
static void printdirs(void);
static Char *dgoto(Char *);
static void skipargs(Char ***, const char *);
static void dnewcwd(struct directory *);
static void dset(Char *);
struct directory dhead; /* "head" of loop */
int printd; /* force name to be printed */
static int dirflag = 0;
struct directory *dcwd;
/*
* dinit - initialize current working directory
*/
void
dinit(Char *hp)
{
static const char emsg[] = "csh: Trying to start from \"%s\"\n";
char path[MAXPATHLEN];
struct directory *dp;
const char *ecp;
Char *cp;
/* Don't believe the login shell home, because it may be a symlink */
ecp = getcwd(path, MAXPATHLEN);
if (ecp == NULL || *ecp == '\0') {
(void)fprintf(csherr, "csh: %s\n", strerror(errno));
if (hp && *hp) {
ecp = short2str(hp);
if (chdir(ecp) == -1)
cp = NULL;
else
cp = Strsave(hp);
(void)fprintf(csherr, emsg, vis_str(hp));
}
else
cp = NULL;
if (cp == NULL) {
(void)fprintf(csherr, emsg, "/");
if (chdir("/") == -1) {
/* I am not even try to print an error message! */
xexit(1);
}
cp = SAVE("/");
}
}
else {
struct stat swd, shp;
/*
* See if $HOME is the working directory we got and use that
*/
if (hp && *hp &&
stat(ecp, &swd) != -1 && stat(short2str(hp), &shp) != -1 &&
swd.st_dev == shp.st_dev && swd.st_ino == shp.st_ino)
cp = Strsave(hp);
else {
const char *cwd;
/*
* use PWD if we have it (for subshells)
*/
if ((cwd = getenv("PWD")) != NULL) {
if (stat(cwd, &shp) != -1 && swd.st_dev == shp.st_dev &&
swd.st_ino == shp.st_ino)
ecp = cwd;
}
cp = dcanon(SAVE(ecp), STRNULL);
}
}
dp = xcalloc(1, sizeof(*dp));
dp->di_name = cp;
dp->di_count = 0;
dhead.di_next = dhead.di_prev = dp;
dp->di_next = dp->di_prev = &dhead;
printd = 0;
dnewcwd(dp);
}
static void
dset(Char *dp)
{
Char **vec;
/*
* Don't call set() directly cause if the directory contains ` or
* other junk characters glob will fail.
*/
vec = xmalloc(2 * sizeof(*vec));
vec[0] = Strsave(dp);
vec[1] = 0;
setq(STRcwd, vec, &shvhed);
Setenv(STRPWD, dp);
}
#define DIR_LONG 1
#define DIR_VERT 2
#define DIR_LINE 4
static void
skipargs(Char ***v, const char *str)
{
Char **n, *s;
n = *v;
dirflag = 0;
for (n++; *n != NULL && (*n)[0] == '-'; n++)
for (s = &((*n)[1]); *s; s++)
switch (*s) {
case 'l':
dirflag |= DIR_LONG;
break;
case 'n':
dirflag |= DIR_LINE;
break;
case 'v':
dirflag |= DIR_VERT;
break;
default:
stderror(ERR_DIRUS, vis_str(**v), str);
/* NOTREACHED */
}
*v = n;
}
/*
* dodirs - list all directories in directory loop
*/
void
/*ARGSUSED*/
dodirs(Char **v, struct command *t)
{
skipargs(&v, "");
if (*v != NULL)
stderror(ERR_DIRUS, "dirs", "");
printdirs();
}
static void
printdirs(void)
{
struct directory *dp;
Char *hp, *s;
size_t cur, idx, len;
hp = value(STRhome);
if (*hp == '\0')
hp = NULL;
dp = dcwd;
idx = 0;
cur = 0;
do {
if (dp == &dhead)
continue;
if (dirflag & DIR_VERT) {
(void)fprintf(cshout, "%zu\t", idx++);
cur = 0;
}
if (!(dirflag & DIR_LONG) && hp != NULL && !eq(hp, STRslash) &&
(len = Strlen(hp), Strncmp(hp, dp->di_name, len) == 0) &&
(dp->di_name[len] == '\0' || dp->di_name[len] == '/'))
len = Strlen(s = (dp->di_name + len)) + 2;
else
len = Strlen(s = dp->di_name) + 1;
cur += len;
if ((dirflag & DIR_LINE) && cur >= 80 - 1 && len < 80) {
(void)fprintf(cshout, "\n");
cur = len;
}
(void) fprintf(cshout, "%s%s%c", (s != dp->di_name)? "~" : "",
vis_str(s), (dirflag & DIR_VERT) ? '\n' : ' ');
} while ((dp = dp->di_prev) != dcwd);
if (!(dirflag & DIR_VERT))
(void)fprintf(cshout, "\n");
}
void
dtildepr(Char *home, Char *dir)
{
if (!eq(home, STRslash) && prefix(home, dir))
(void)fprintf(cshout, "~%s", vis_str(dir + Strlen(home)));
else
(void)fprintf(cshout, "%s", vis_str(dir));
}
void
dtilde(void)
{
struct directory *d;
d = dcwd;
do {
if (d == &dhead)
continue;
d->di_name = dcanon(d->di_name, STRNULL);
} while ((d = d->di_prev) != dcwd);
dset(dcwd->di_name);
}
/* dnormalize():
* If the name starts with . or .. then we might need to normalize
* it depending on the symbolic link flags
*/
Char *
dnormalize(Char *cp)
{
#define UC (unsigned char)
#define ISDOT(c) (UC(c)[0] == '.' && ((UC(c)[1] == '\0') || (UC(c)[1] == '/')))
#define ISDOTDOT(c) (UC(c)[0] == '.' && ISDOT(&((c)[1])))
if ((unsigned char) cp[0] == '/')
return (Strsave(cp));
if (adrof(STRignore_symlinks)) {
size_t dotdot = 0;
Char *dp, *cwd;
cwd = xmalloc((size_t)((Strlen(dcwd->di_name) + 3) *
sizeof(Char)));
(void)Strcpy(cwd, dcwd->di_name);
/*
* Ignore . and count ..'s
*/
while (*cp) {
if (ISDOT(cp)) {
if (*++cp)
cp++;
}
else if (ISDOTDOT(cp)) {
dotdot++;
cp += 2;
if (*cp)
cp++;
}
else
break;
}
while (dotdot > 0) {
dp = Strrchr(cwd, '/');
if (dp) {
*dp = '\0';
dotdot--;
}
else
break;
}
if (*cp) {
cwd[dotdot = Strlen(cwd)] = '/';
cwd[dotdot + 1] = '\0';
dp = Strspl(cwd, cp);
free(cwd);
return dp;
}
else {
if (!*cwd) {
cwd[0] = '/';
cwd[1] = '\0';
}
return cwd;
}
}
return Strsave(cp);
}
/*
* dochngd - implement chdir command.
*/
void
/*ARGSUSED*/
dochngd(Char **v, struct command *t)
{
struct directory *dp;
Char *cp;
skipargs(&v, " [<dir>]");
printd = 0;
if (*v == NULL) {
if ((cp = value(STRhome)) == NULL || *cp == 0)
stderror(ERR_NAME | ERR_NOHOMEDIR);
if (chdir(short2str(cp)) < 0)
stderror(ERR_NAME | ERR_CANTCHANGE);
cp = Strsave(cp);
}
else if (v[1] != NULL)
stderror(ERR_NAME | ERR_TOOMANY);
else if ((dp = dfind(*v)) != 0) {
char *tmp;
printd = 1;
if (chdir(tmp = short2str(dp->di_name)) < 0)
stderror(ERR_SYSTEM, tmp, strerror(errno));
dcwd->di_prev->di_next = dcwd->di_next;
dcwd->di_next->di_prev = dcwd->di_prev;
dfree(dcwd);
dnewcwd(dp);
return;
}
else
cp = dfollow(*v);
dp = xcalloc(1, sizeof(*dp));
dp->di_name = cp;
dp->di_count = 0;
dp->di_next = dcwd->di_next;
dp->di_prev = dcwd->di_prev;
dp->di_prev->di_next = dp;
dp->di_next->di_prev = dp;
dfree(dcwd);
dnewcwd(dp);
}
static Char *
dgoto(Char *cp)
{
Char *dp;
if (*cp != '/') {
Char *p, *q;
size_t cwdlen;
for (p = dcwd->di_name; *p++;)
continue;
if ((cwdlen = (size_t)(p - dcwd->di_name - 1)) == 1) /* root */
cwdlen = 0;
for (p = cp; *p++;)
continue;
dp = xmalloc((size_t)(cwdlen + (size_t)(p - cp) + 1) * sizeof(Char));
for (p = dp, q = dcwd->di_name; (*p++ = *q++) != '\0';)
continue;
if (cwdlen)
p[-1] = '/';
else
p--; /* don't add a / after root */
for (q = cp; (*p++ = *q++) != '\0';)
continue;
free(cp);
cp = dp;
dp += cwdlen;
}
else
dp = cp;
cp = dcanon(cp, dp);
return cp;
}
/*
* dfollow - change to arg directory; fall back on cdpath if not valid
*/
static Char *
dfollow(Char *cp)
{
char ebuf[MAXPATHLEN];
struct varent *c;
Char *dp;
int serrno;
cp = globone(cp, G_ERROR);
/*
* if we are ignoring symlinks, try to fix relatives now.
*/
dp = dnormalize(cp);
if (chdir(short2str(dp)) >= 0) {
free(cp);
return dgoto(dp);
}
else {
free(dp);
if (chdir(short2str(cp)) >= 0)
return dgoto(cp);
serrno = errno;
}
if (cp[0] != '/' && !prefix(STRdotsl, cp) && !prefix(STRdotdotsl, cp)
&& (c = adrof(STRcdpath))) {
Char **cdp;
Char *p;
Char buf[MAXPATHLEN];
for (cdp = c->vec; *cdp; cdp++) {
for (dp = buf, p = *cdp; (*dp++ = *p++) != '\0';)
continue;
dp[-1] = '/';
for (p = cp; (*dp++ = *p++) != '\0';)
continue;
if (chdir(short2str(buf)) >= 0) {
printd = 1;
free(cp);
cp = Strsave(buf);
return dgoto(cp);
}
}
}
dp = value(cp);
if ((dp[0] == '/' || dp[0] == '.') && chdir(short2str(dp)) >= 0) {
free(cp);
cp = Strsave(dp);
printd = 1;
return dgoto(cp);
}
(void)strcpy(ebuf, short2str(cp));
free(cp);
stderror(ERR_SYSTEM, ebuf, strerror(serrno));
/* NOTREACHED */
}
/*
* dopushd - push new directory onto directory stack.
* with no arguments exchange top and second.
* with numeric argument (+n) bring it to top.
*/
void
/*ARGSUSED*/
dopushd(Char **v, struct command *t)
{
struct directory *dp;
skipargs(&v, " [<dir>|+<n>]");
printd = 1;
if (*v == NULL) {
char *tmp;
if ((dp = dcwd->di_prev) == &dhead)
dp = dhead.di_prev;
if (dp == dcwd)
stderror(ERR_NAME | ERR_NODIR);
if (chdir(tmp = short2str(dp->di_name)) < 0)
stderror(ERR_SYSTEM, tmp, strerror(errno));
dp->di_prev->di_next = dp->di_next;
dp->di_next->di_prev = dp->di_prev;
dp->di_next = dcwd->di_next;
dp->di_prev = dcwd;
dcwd->di_next->di_prev = dp;
dcwd->di_next = dp;
}
else if (v[1] != NULL)
stderror(ERR_NAME | ERR_TOOMANY);
else if ((dp = dfind(*v)) != NULL) {
char *tmp;
if (chdir(tmp = short2str(dp->di_name)) < 0)
stderror(ERR_SYSTEM, tmp, strerror(errno));
}
else {
Char *ccp;
ccp = dfollow(*v);
dp = xcalloc(1, sizeof(*dp));
dp->di_name = ccp;
dp->di_count = 0;
dp->di_prev = dcwd;
dp->di_next = dcwd->di_next;
dcwd->di_next = dp;
dp->di_next->di_prev = dp;
}
dnewcwd(dp);
}
/*
* dfind - find a directory if specified by numeric (+n) argument
*/
static struct directory *
dfind(Char *cp)
{
struct directory *dp;
Char *ep;
int i;
if (*cp++ != '+')
return (0);
for (ep = cp; Isdigit(*ep); ep++)
continue;
if (*ep)
return (0);
i = getn(cp);
if (i <= 0)
return (0);
for (dp = dcwd; i != 0; i--) {
if ((dp = dp->di_prev) == &dhead)
dp = dp->di_prev;
if (dp == dcwd)
stderror(ERR_NAME | ERR_DEEP);
}
return (dp);
}
/*
* dopopd - pop a directory out of the directory stack
* with a numeric argument just discard it.
*/
void
/*ARGSUSED*/
dopopd(Char **v, struct command *t)
{
struct directory *dp, *p = NULL;
skipargs(&v, " [+<n>]");
printd = 1;
if (*v == NULL)
dp = dcwd;
else if (v[1] != NULL)
stderror(ERR_NAME | ERR_TOOMANY);
else if ((dp = dfind(*v)) == 0)
stderror(ERR_NAME | ERR_BADDIR);
if (dp->di_prev == &dhead && dp->di_next == &dhead)
stderror(ERR_NAME | ERR_EMPTY);
if (dp == dcwd) {
char *tmp;
if ((p = dp->di_prev) == &dhead)
p = dhead.di_prev;
if (chdir(tmp = short2str(p->di_name)) < 0)
stderror(ERR_SYSTEM, tmp, strerror(errno));
}
dp->di_prev->di_next = dp->di_next;
dp->di_next->di_prev = dp->di_prev;
if (dp == dcwd)
dnewcwd(p);
else {
printdirs();
}
dfree(dp);
}
/*
* dfree - free the directory (or keep it if it still has ref count)
*/
void
dfree(struct directory *dp)
{
if (dp->di_count != 0) {
dp->di_next = dp->di_prev = 0;
}
else {
free(dp->di_name);
free(dp);
}
}
/*
* dcanon - canonicalize the pathname, removing excess ./ and ../ etc.
* we are of course assuming that the file system is standardly
* constructed (always have ..'s, directories have links)
*/
Char *
dcanon(Char *cp, Char *p)
{
Char slink[MAXPATHLEN];
char tlink[MAXPATHLEN];
Char *newcp, *sp;
Char *p1, *p2; /* general purpose */
ssize_t cc;
size_t len;
int slash;
/*
* christos: if the path given does not start with a slash prepend cwd. If
* cwd does not start with a path or the result would be too long abort().
*/
if (*cp != '/') {
Char tmpdir[MAXPATHLEN];
p1 = value(STRcwd);
if (p1 == NULL || *p1 != '/')
abort();
if (Strlen(p1) + Strlen(cp) + 1 >= MAXPATHLEN)
abort();
(void)Strcpy(tmpdir, p1);
(void)Strcat(tmpdir, STRslash);
(void)Strcat(tmpdir, cp);
free(cp);
cp = p = Strsave(tmpdir);
}
while (*p) { /* for each component */
sp = p; /* save slash address */
while (*++p == '/') /* flush extra slashes */
continue;
if (p != ++sp)
for (p1 = sp, p2 = p; (*p1++ = *p2++) != '\0';)
continue;
p = sp; /* save start of component */
slash = 0;
while (*++p) /* find next slash or end of path */
if (*p == '/') {
slash = 1;
*p = 0;
break;
}
if (*sp == '\0') { /* if component is null */
if (--sp == cp) /* if path is one char (i.e. /) */
break;
else
*sp = '\0';
} else if (sp[0] == '.' && sp[1] == 0) {
if (slash) {
for (p1 = sp, p2 = p + 1; (*p1++ = *p2++) != '\0';)
continue;
p = --sp;
}
else if (--sp != cp)
*sp = '\0';
}
else if (sp[0] == '.' && sp[1] == '.' && sp[2] == 0) {
/*
* We have something like "yyy/xxx/..", where "yyy" can be null or
* a path starting at /, and "xxx" is a single component. Before
* compressing "xxx/..", we want to expand "yyy/xxx", if it is a
* symbolic link.
*/
*--sp = 0; /* form the pathname for readlink */
if (sp != cp && !adrof(STRignore_symlinks) &&
(cc = readlink(short2str(cp), tlink,
sizeof(tlink) - 1)) >= 0) {
tlink[cc] = '\0';
(void)Strcpy(slink, str2short(tlink));
if (slash)
*p = '/';
/*
* Point p to the '/' in "/..", and restore the '/'.
*/
*(p = sp) = '/';
/*
* find length of p
*/
for (p1 = p; *p1++;)
continue;
if (*slink != '/') {
/*
* Relative path, expand it between the "yyy/" and the
* "/..". First, back sp up to the character past "yyy/".
*/
while (*--sp != '/')
continue;
sp++;
*sp = 0;
/*
* New length is "yyy/" + slink + "/.." and rest
*/
p1 = newcp = xmalloc(
(size_t)((sp - cp) + cc + (p1 - p)) * sizeof(Char));
/*
* Copy new path into newcp
*/
for (p2 = cp; (*p1++ = *p2++) != '\0';)
continue;
for (p1--, p2 = slink; (*p1++ = *p2++) != '\0';)
continue;
for (p1--, p2 = p; (*p1++ = *p2++) != '\0';)
continue;
/*
* Restart canonicalization at expanded "/xxx".
*/
p = sp - cp - 1 + newcp;
}
else {
/*
* New length is slink + "/.." and rest
*/
p1 = newcp = xmalloc(
(size_t)(cc + (p1 - p)) * sizeof(Char));
/*
* Copy new path into newcp
*/
for (p2 = slink; (*p1++ = *p2++) != '\0';)
continue;
for (p1--, p2 = p; (*p1++ = *p2++) != '\0';)
continue;
/*
* Restart canonicalization at beginning
*/
p = newcp;
}
free(cp);
cp = newcp;
continue; /* canonicalize the link */
}
*sp = '/';
if (sp != cp)
while (*--sp != '/')
continue;
if (slash) {
for (p1 = sp + 1, p2 = p + 1; (*p1++ = *p2++) != '\0';)
continue;
p = sp;
}
else if (cp == sp)
*++sp = '\0';
else
*sp = '\0';
}
else { /* normal dir name (not . or .. or nothing) */
if (sp != cp && adrof(STRchase_symlinks) &&
!adrof(STRignore_symlinks) &&
(cc = readlink(short2str(cp), tlink, sizeof(tlink)-1)) >= 0) {
tlink[cc] = '\0';
(void)Strcpy(slink, str2short(tlink));
/*
* restore the '/'.
*/
if (slash)
*p = '/';
/*
* point sp to p (rather than backing up).
*/
sp = p;
/*
* find length of p
*/
for (p1 = p; *p1++;)
continue;
if (*slink != '/') {
/*
* Relative path, expand it between the "yyy/" and the
* remainder. First, back sp up to the character past
* "yyy/".
*/
while (*--sp != '/')
continue;
sp++;
*sp = 0;
/*
* New length is "yyy/" + slink + "/.." and rest
*/
p1 = newcp = xmalloc(
(size_t)((sp - cp) + cc + (p1 - p)) * sizeof(Char));
/*
* Copy new path into newcp
*/
for (p2 = cp; (*p1++ = *p2++) != '\0';)
continue;
for (p1--, p2 = slink; (*p1++ = *p2++) != '\0';)
continue;
for (p1--, p2 = p; (*p1++ = *p2++) != '\0';)
continue;
/*
* Restart canonicalization at expanded "/xxx".
*/
p = sp - cp - 1 + newcp;
}
else {
/*
* New length is slink + the rest
*/
p1 = newcp = xmalloc(
(size_t)(cc + (p1 - p)) * sizeof(Char));
/*
* Copy new path into newcp
*/
for (p2 = slink; (*p1++ = *p2++) != '\0';)
continue;
for (p1--, p2 = p; (*p1++ = *p2++) != '\0';)
continue;
/*
* Restart canonicalization at beginning
*/
p = newcp;
}
free(cp);
cp = newcp;
continue; /* canonicalize the link */
}
if (slash)
*p = '/';
}
}
/*
* fix home...
*/
p1 = value(STRhome);
len = Strlen(p1);
/*
* See if we're not in a subdir of STRhome
*/
if (p1 && *p1 == '/' &&
(Strncmp(p1, cp, len) != 0 || (cp[len] != '/' && cp[len] != '\0'))) {
static ino_t home_ino;
static dev_t home_dev = NODEV;
static Char *home_ptr = NULL;
struct stat statbuf;
/*
* Get dev and ino of STRhome
*/
if (home_ptr != p1 &&
stat(short2str(p1), &statbuf) != -1) {
home_dev = statbuf.st_dev;
home_ino = statbuf.st_ino;
home_ptr = p1;
}
/*
* Start comparing dev & ino backwards
*/
p2 = Strcpy(slink, cp);
for (sp = NULL; *p2 && stat(short2str(p2), &statbuf) != -1;) {
if (statbuf.st_dev == home_dev &&
statbuf.st_ino == home_ino) {
sp = (Char *) - 1;
break;
}
if ((sp = Strrchr(p2, '/')) != NULL)
*sp = '\0';
}
/*
* See if we found it
*/
if (*p2 && sp == (Char *) -1) {
/*
* Use STRhome to make '~' work
*/
newcp = Strspl(p1, cp + Strlen(p2));
free(cp);
cp = newcp;
}
}
return cp;
}
/*
* dnewcwd - make a new directory in the loop the current one
*/
static void
dnewcwd(struct directory *dp)
{
dcwd = dp;
dset(dcwd->di_name);
if (printd && !(adrof(STRpushdsilent)))
printdirs();
}