[apple/shell_cmds.git] / sh / cd.c

/*-
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Kenneth Almquist.
 *
 * 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.
 * 4. 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.
 */

#ifndef lint
#if 0
static char sccsid[] = "@(#)cd.c	8.2 (Berkeley) 5/4/95";
#endif
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/types.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <limits.h>

/*
 * The cd and pwd commands.
 */

#include "shell.h"
#include "var.h"
#include "nodes.h"	/* for jobs.h */
#include "jobs.h"
#include "options.h"
#include "output.h"
#include "memalloc.h"
#include "error.h"
#include "exec.h"
#include "redir.h"
#include "mystring.h"
#include "show.h"
#include "cd.h"
#include "builtins.h"

static int cdlogical(char *);
static int cdphysical(char *);
static int docd(char *, int, int);
static char *getcomponent(void);
static char *findcwd(char *);
static void updatepwd(char *);
static char *getpwd(void);
static char *getpwd2(void);

static char *curdir = NULL;	/* current working directory */
static char *prevdir;		/* previous working directory */
static char *cdcomppath;

int
cdcmd(int argc __unused, char **argv __unused)
{
	const char *dest;
	const char *path;
	char *p;
	struct stat statb;
	int ch, phys, print = 0, getcwderr = 0;
	int rc;
	int errno1 = ENOENT;

	phys = Pflag;
	while ((ch = nextopt("eLP")) != '\0') {
		switch (ch) {
		case 'e':
			getcwderr = 1;
			break;
		case 'L':
			phys = 0;
			break;
		case 'P':
			phys = 1;
			break;
		}
	}

	if (*argptr != NULL && argptr[1] != NULL)
		error("too many arguments");

	if ((dest = *argptr) == NULL && (dest = bltinlookup("HOME", 1)) == NULL)
		error("HOME not set");
	if (*dest == '\0')
		dest = ".";
	if (dest[0] == '-' && dest[1] == '\0') {
		dest = prevdir ? prevdir : curdir;
		if (dest)
			print = 1;
		else
			dest = ".";
	}
	if (dest[0] == '/' ||
	    (dest[0] == '.' && (dest[1] == '/' || dest[1] == '\0')) ||
	    (dest[0] == '.' && dest[1] == '.' && (dest[2] == '/' || dest[2] == '\0')) ||
	    (path = bltinlookup("CDPATH", 1)) == NULL)
		path = "";
	while ((p = padvance(&path, dest)) != NULL) {
		if (stat(p, &statb) < 0) {
			if (errno != ENOENT)
				errno1 = errno;
		} else if (!S_ISDIR(statb.st_mode))
			errno1 = ENOTDIR;
		else {
			if (!print) {
				/*
				 * XXX - rethink
				 */
				if (p[0] == '.' && p[1] == '/' && p[2] != '\0')
					print = strcmp(p + 2, dest);
				else
					print = strcmp(p, dest);
			}
			rc = docd(p, print, phys);
			if (rc >= 0)
				return getcwderr ? rc : 0;
			if (errno != ENOENT)
				errno1 = errno;
		}
	}
	error("%s: %s", dest, strerror(errno1));
	/*NOTREACHED*/
	return 0;
}


/*
 * Actually change the directory.  In an interactive shell, print the
 * directory name if "print" is nonzero.
 */
static int
docd(char *dest, int print, int phys)
{
	int rc;

	TRACE(("docd(\"%s\", %d, %d) called\n", dest, print, phys));

	/* If logical cd fails, fall back to physical. */
	if ((phys || (rc = cdlogical(dest)) < 0) && (rc = cdphysical(dest)) < 0)
		return (-1);

	if (print && iflag && curdir)
		out1fmt("%s\n", curdir);

	return (rc);
}

static int
cdlogical(char *dest)
{
	char *p;
	char *q;
	char *component;
	struct stat statb;
	int first;
	int badstat;

	/*
	 *  Check each component of the path. If we find a symlink or
	 *  something we can't stat, clear curdir to force a getcwd()
	 *  next time we get the value of the current directory.
	 */
	badstat = 0;
	cdcomppath = stsavestr(dest);
	STARTSTACKSTR(p);
	if (*dest == '/') {
		STPUTC('/', p);
		cdcomppath++;
	}
	first = 1;
	while ((q = getcomponent()) != NULL) {
		if (q[0] == '\0' || (q[0] == '.' && q[1] == '\0'))
			continue;
		if (! first)
			STPUTC('/', p);
		first = 0;
		component = q;
		STPUTS(q, p);
		if (equal(component, ".."))
			continue;
		STACKSTRNUL(p);
		if (lstat(stackblock(), &statb) < 0) {
			badstat = 1;
			break;
		}
	}

	INTOFF;
	if ((p = findcwd(badstat ? NULL : dest)) == NULL || chdir(p) < 0) {
		INTON;
		return (-1);
	}
	updatepwd(p);
	INTON;
	return (0);
}

static int
cdphysical(char *dest)
{
	char *p;
	int rc = 0;

	INTOFF;
	if (chdir(dest) < 0) {
		INTON;
		return (-1);
	}
	p = findcwd(NULL);
	if (p == NULL) {
		warning("warning: failed to get name of current directory");
		rc = 1;
	}
	updatepwd(p);
	INTON;
	return (rc);
}

/*
 * Get the next component of the path name pointed to by cdcomppath.
 * This routine overwrites the string pointed to by cdcomppath.
 */
static char *
getcomponent(void)
{
	char *p;
	char *start;

	if ((p = cdcomppath) == NULL)
		return NULL;
	start = cdcomppath;
	while (*p != '/' && *p != '\0')
		p++;
	if (*p == '\0') {
		cdcomppath = NULL;
	} else {
		*p++ = '\0';
		cdcomppath = p;
	}
	return start;
}


static char *
findcwd(char *dir)
{
	char *new;
	char *p;

	/*
	 * If our argument is NULL, we don't know the current directory
	 * any more because we traversed a symbolic link or something
	 * we couldn't stat().
	 */
	if (dir == NULL || curdir == NULL)
		return getpwd2();
	cdcomppath = stsavestr(dir);
	STARTSTACKSTR(new);
	if (*dir != '/') {
		STPUTS(curdir, new);
		if (STTOPC(new) == '/')
			STUNPUTC(new);
	}
	while ((p = getcomponent()) != NULL) {
		if (equal(p, "..")) {
			while (new > stackblock() && (STUNPUTC(new), *new) != '/');
		} else if (*p != '\0' && ! equal(p, ".")) {
			STPUTC('/', new);
			STPUTS(p, new);
		}
	}
	if (new == stackblock())
		STPUTC('/', new);
	STACKSTRNUL(new);
	return stackblock();
}

/*
 * Update curdir (the name of the current directory) in response to a
 * cd command.  We also call hashcd to let the routines in exec.c know
 * that the current directory has changed.
 */
static void
updatepwd(char *dir)
{
	hashcd();				/* update command hash table */

	if (prevdir)
		ckfree(prevdir);
	prevdir = curdir;
	curdir = dir ? savestr(dir) : NULL;
	setvar("PWD", curdir, VEXPORT);
	setvar("OLDPWD", prevdir, VEXPORT);
}

int
pwdcmd(int argc __unused, char **argv __unused)
{
	char *p;
	int ch, phys;

	phys = Pflag;
	while ((ch = nextopt("LP")) != '\0') {
		switch (ch) {
		case 'L':
			phys = 0;
			break;
		case 'P':
			phys = 1;
			break;
		}
	}

	if (*argptr != NULL)
		error("too many arguments");

	if (!phys && getpwd()) {
		out1str(curdir);
		out1c('\n');
	} else {
		if ((p = getpwd2()) == NULL)
			error(".: %s", strerror(errno));
		out1str(p);
		out1c('\n');
	}

	return 0;
}

/*
 * Get the current directory and cache the result in curdir.
 */
static char *
getpwd(void)
{
	char *p;

	if (curdir)
		return curdir;

	p = getpwd2();
	if (p != NULL)
		curdir = savestr(p);

	return curdir;
}

#define MAXPWD 256

/*
 * Return the current directory.
 */
static char *
getpwd2(void)
{
	char *pwd;
	int i;

	for (i = MAXPWD;; i *= 2) {
		pwd = stalloc(i);
		if (getcwd(pwd, i) != NULL)
			return pwd;
		stunalloc(pwd);
		if (errno != ERANGE)
			break;
	}

	return NULL;
}

/*
 * Initialize PWD in a new shell.
 * If the shell is interactive, we need to warn if this fails.
 */
void
pwd_init(int warn)
{
	char *pwd;
	struct stat stdot, stpwd;

	pwd = lookupvar("PWD");
	if (pwd && *pwd == '/' && stat(".", &stdot) != -1 &&
	    stat(pwd, &stpwd) != -1 &&
	    stdot.st_dev == stpwd.st_dev &&
	    stdot.st_ino == stpwd.st_ino) {
		if (curdir)
			ckfree(curdir);
		curdir = savestr(pwd);
	}
	if (getpwd() == NULL && warn)
		out2fmt_flush("sh: cannot determine working directory\n");
	setvar("PWD", curdir, VEXPORT);
}
Commit	Line	Data
71aad674 A	1	/*-
	2	* Copyright (c) 1991, 1993
	3	* The Regents of the University of California. All rights reserved.
	4	*
	5	* This code is derived from software contributed to Berkeley by
	6	* Kenneth Almquist.
	7	*
	8	* Redistribution and use in source and binary forms, with or without
	9	* modification, are permitted provided that the following conditions
	10	* are met:
	11	* 1. Redistributions of source code must retain the above copyright
	12	* notice, this list of conditions and the following disclaimer.
	13	* 2. Redistributions in binary form must reproduce the above copyright
	14	* notice, this list of conditions and the following disclaimer in the
	15	* documentation and/or other materials provided with the distribution.
	16	* 4. Neither the name of the University nor the names of its contributors
	17	* may be used to endorse or promote products derived from this software
	18	* without specific prior written permission.
	19	*
	20	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	21	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	22	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	23	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	24	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	25	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	26	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	27	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	28	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	29	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	30	* SUCH DAMAGE.
	31	*/
	32
	33	#ifndef lint
	34	#if 0
	35	static char sccsid[] = "@(#)cd.c 8.2 (Berkeley) 5/4/95";
	36	#endif
	37	#endif /* not lint */
	38	#include <sys/cdefs.h>
	39	__FBSDID("$FreeBSD$");
	40
	41	#include <sys/types.h>
	42	#include <sys/stat.h>
	43	#include <stdlib.h>
	44	#include <string.h>
	45	#include <unistd.h>
	46	#include <errno.h>
	47	#include <limits.h>
	48
	49	/*
	50	* The cd and pwd commands.
	51	*/
	52
	53	#include "shell.h"
	54	#include "var.h"
	55	#include "nodes.h" /* for jobs.h */
	56	#include "jobs.h"
	57	#include "options.h"
	58	#include "output.h"
	59	#include "memalloc.h"
	60	#include "error.h"
	61	#include "exec.h"
	62	#include "redir.h"
	63	#include "mystring.h"
	64	#include "show.h"
65	#include "cd.h"
66	#include "builtins.h"
67
68	static int cdlogical(char *);
69	static int cdphysical(char *);
70	static int docd(char *, int, int);
71	static char *getcomponent(void);
72	static char findcwd(char );
73	static void updatepwd(char *);
74	static char *getpwd(void);
75	static char *getpwd2(void);
76
77	static char curdir = NULL; / current working directory */
78	static char prevdir; / previous working directory */
79	static char *cdcomppath;
80
81	int
82	cdcmd(int argc __unused, char **argv __unused)
83	{
84	const char *dest;
85	const char *path;
86	char *p;
87	struct stat statb;
88	int ch, phys, print = 0, getcwderr = 0;
89	int rc;
90	int errno1 = ENOENT;
91
92	phys = Pflag;
93	while ((ch = nextopt("eLP")) != '\0') {
94	switch (ch) {
95	case 'e':
96	getcwderr = 1;
97	break;
98	case 'L':
99	phys = 0;
100	break;
101	case 'P':
102	phys = 1;
103	break;
104	}
105	}
106
107	if (*argptr != NULL && argptr[1] != NULL)
108	error("too many arguments");
109
110	if ((dest = *argptr) == NULL && (dest = bltinlookup("HOME", 1)) == NULL)
111	error("HOME not set");
112	if (*dest == '\0')
113	dest = ".";
114	if (dest[0] == '-' && dest[1] == '\0') {
115	dest = prevdir ? prevdir : curdir;
116	if (dest)
117	print = 1;
118	else
119	dest = ".";
120	}
121	if (dest[0] == '/' \|\|
122	(dest[0] == '.' && (dest[1] == '/' \|\| dest[1] == '\0')) \|\|
123	(dest[0] == '.' && dest[1] == '.' && (dest[2] == '/' \|\| dest[2] == '\0')) \|\|
124	(path = bltinlookup("CDPATH", 1)) == NULL)
125	path = "";
126	while ((p = padvance(&path, dest)) != NULL) {
127	if (stat(p, &statb) < 0) {
128	if (errno != ENOENT)
129	errno1 = errno;
130	} else if (!S_ISDIR(statb.st_mode))
131	errno1 = ENOTDIR;
132	else {
133	if (!print) {
134	/*
135	* XXX - rethink
136	*/
137	if (p[0] == '.' && p[1] == '/' && p[2] != '\0')
138	print = strcmp(p + 2, dest);
139	else
140	print = strcmp(p, dest);
141	}
142	rc = docd(p, print, phys);
143	if (rc >= 0)
144	return getcwderr ? rc : 0;
145	if (errno != ENOENT)
146	errno1 = errno;
147	}
148	}
149	error("%s: %s", dest, strerror(errno1));
150	/NOTREACHED/
151	return 0;
152	}
153
154
155	/*
156	* Actually change the directory. In an interactive shell, print the
157	* directory name if "print" is nonzero.
158	*/
159	static int
160	docd(char *dest, int print, int phys)
161	{
162	int rc;
163
164	TRACE(("docd(\"%s\", %d, %d) called\n", dest, print, phys));
165
166	/* If logical cd fails, fall back to physical. */
167	if ((phys \|\| (rc = cdlogical(dest)) < 0) && (rc = cdphysical(dest)) < 0)
168	return (-1);
169
170	if (print && iflag && curdir)
171	out1fmt("%s\n", curdir);
172
173	return (rc);
174	}
175
176	static int
177	cdlogical(char *dest)
178	{
179	char *p;
180	char *q;
181	char *component;
182	struct stat statb;
183	int first;
184	int badstat;
185
186	/*
187	* Check each component of the path. If we find a symlink or
188	* something we can't stat, clear curdir to force a getcwd()
189	* next time we get the value of the current directory.
190	*/
191	badstat = 0;
192	cdcomppath = stsavestr(dest);
193	STARTSTACKSTR(p);
194	if (*dest == '/') {
195	STPUTC('/', p);
196	cdcomppath++;
197	}
198	first = 1;
199	while ((q = getcomponent()) != NULL) {
200	if (q[0] == '\0' \|\| (q[0] == '.' && q[1] == '\0'))
201	continue;
202	if (! first)
203	STPUTC('/', p);
204	first = 0;
205	component = q;
206	STPUTS(q, p);
207	if (equal(component, ".."))
208	continue;
209	STACKSTRNUL(p);
210	if (lstat(stackblock(), &statb) < 0) {
211	badstat = 1;
212	break;
213	}
214	}
215
216	INTOFF;
217	if ((p = findcwd(badstat ? NULL : dest)) == NULL \|\| chdir(p) < 0) {
218	INTON;
219	return (-1);
220	}
221	updatepwd(p);
222	INTON;
223	return (0);
224	}
225
226	static int
227	cdphysical(char *dest)
228	{
229	char *p;
230	int rc = 0;
231
232	INTOFF;
233	if (chdir(dest) < 0) {
234	INTON;
235	return (-1);
236	}
237	p = findcwd(NULL);
238	if (p == NULL) {
239	warning("warning: failed to get name of current directory");
240	rc = 1;
241	}
242	updatepwd(p);
243	INTON;
244	return (rc);
245	}
246
247	/*
248	* Get the next component of the path name pointed to by cdcomppath.
249	* This routine overwrites the string pointed to by cdcomppath.
250	*/
251	static char *
252	getcomponent(void)
253	{
254	char *p;
255	char *start;
256
257	if ((p = cdcomppath) == NULL)
258	return NULL;
259	start = cdcomppath;
260	while (p != '/' && p != '\0')
261	p++;
262	if (*p == '\0') {
263	cdcomppath = NULL;
264	} else {
265	*p++ = '\0';
266	cdcomppath = p;
267	}
268	return start;
269	}
270
271
272	static char *
273	findcwd(char *dir)
274	{
275	char *new;
276	char *p;
277
278	/*
279	* If our argument is NULL, we don't know the current directory
280	* any more because we traversed a symbolic link or something
281	* we couldn't stat().
282	*/
283	if (dir == NULL \|\| curdir == NULL)
284	return getpwd2();
285	cdcomppath = stsavestr(dir);
286	STARTSTACKSTR(new);
287	if (*dir != '/') {
288	STPUTS(curdir, new);
289	if (STTOPC(new) == '/')
290	STUNPUTC(new);
291	}
292	while ((p = getcomponent()) != NULL) {
293	if (equal(p, "..")) {
294	while (new > stackblock() && (STUNPUTC(new), *new) != '/');
295	} else if (*p != '\0' && ! equal(p, ".")) {
296	STPUTC('/', new);
297	STPUTS(p, new);
298	}
299	}
300	if (new == stackblock())
301	STPUTC('/', new);
302	STACKSTRNUL(new);
303	return stackblock();
304	}
305
306	/*
307	* Update curdir (the name of the current directory) in response to a
308	* cd command. We also call hashcd to let the routines in exec.c know
309	* that the current directory has changed.
310	*/
311	static void
312	updatepwd(char *dir)
313	{
314	hashcd(); /* update command hash table */
315
316	if (prevdir)
317	ckfree(prevdir);
318	prevdir = curdir;
319	curdir = dir ? savestr(dir) : NULL;
320	setvar("PWD", curdir, VEXPORT);
321	setvar("OLDPWD", prevdir, VEXPORT);
322	}
323
324	int
325	pwdcmd(int argc __unused, char **argv __unused)
326	{
327	char *p;
328	int ch, phys;
329
330	phys = Pflag;
331	while ((ch = nextopt("LP")) != '\0') {
332	switch (ch) {
333	case 'L':
334	phys = 0;
335	break;
336	case 'P':
337	phys = 1;
338	break;
339	}
340	}
341
342	if (*argptr != NULL)
343	error("too many arguments");
344
345	if (!phys && getpwd()) {
346	out1str(curdir);
347	out1c('\n');
348	} else {
349	if ((p = getpwd2()) == NULL)
350	error(".: %s", strerror(errno));
351	out1str(p);
352	out1c('\n');
353	}
354
355	return 0;
356	}
357
358	/*
359	* Get the current directory and cache the result in curdir.
360	*/
361	static char *
362	getpwd(void)
363	{
364	char *p;
365
366	if (curdir)
367	return curdir;
368
369	p = getpwd2();
370	if (p != NULL)
371	curdir = savestr(p);
372
373	return curdir;
374	}
375
376	#define MAXPWD 256
377
378	/*
379	* Return the current directory.
380	*/
381	static char *
382	getpwd2(void)
383	{
384	char *pwd;
385	int i;
386
387	for (i = MAXPWD;; i *= 2) {
388	pwd = stalloc(i);
389	if (getcwd(pwd, i) != NULL)
390	return pwd;
391	stunalloc(pwd);
392	if (errno != ERANGE)
393	break;
394	}
395
396	return NULL;
397	}
398
399	/*
400	* Initialize PWD in a new shell.
401	* If the shell is interactive, we need to warn if this fails.
402	*/
403	void
404	pwd_init(int warn)
405	{
406	char *pwd;
407	struct stat stdot, stpwd;
408
409	pwd = lookupvar("PWD");
410	if (pwd && *pwd == '/' && stat(".", &stdot) != -1 &&
411	stat(pwd, &stpwd) != -1 &&
412	stdot.st_dev == stpwd.st_dev &&
413	stdot.st_ino == stpwd.st_ino) {
414	if (curdir)
415	ckfree(curdir);
416	curdir = savestr(pwd);
417	}
418	if (getpwd() == NULL && warn)
419	out2fmt_flush("sh: cannot determine working directory\n");
420	setvar("PWD", curdir, VEXPORT);
421	}