/*- * See the file LICENSE for redistribution information. * * Copyright (c) 1996-2002 *	Sleepycat Software.  All rights reserved. *//* * Copyright (c) 1989, 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 "db_config.h"#ifndef lintstatic const char revid[] = "$Id: getcwd.c,v 1.1.1.1 2004/08/19 23:53:55 gopalan Exp $";#endif /* not lint */#ifndef NO_SYSTEM_INCLUDES#include <sys/types.h>#include <sys/stat.h>#if HAVE_DIRENT_H# include <dirent.h># define NAMLEN(dirent) strlen((dirent)->d_name)#else# define dirent direct# define NAMLEN(dirent) (dirent)->d_namlen# if HAVE_SYS_NDIR_H#  include <sys/ndir.h># endif# if HAVE_SYS_DIR_H#  include <sys/dir.h># endif# if HAVE_NDIR_H#  include <ndir.h># endif#endif#include <stdio.h>#include <stdlib.h>#include <string.h>#include <unistd.h>#endif#include "db_int.h"#define	ISDOT(dp) \	(dp->d_name[0] == '.' && (dp->d_name[1] == '\0' || \	    (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))#ifndef dirfd#define   dirfd(dirp)     ((dirp)->dd_fd)#endif/* * getcwd -- *	Get the current working directory. * * PUBLIC: #ifndef HAVE_GETCWD * PUBLIC: char *getcwd __P((char *, size_t)); * PUBLIC: #endif */char *getcwd(pt, size)	char *pt;	size_t size;{	register struct dirent *dp;	register DIR *dir;	register dev_t dev;	register ino_t ino;	register int first;	register char *bpt, *bup;	struct stat s;	dev_t root_dev;	ino_t root_ino;	size_t ptsize, upsize;	int ret, save_errno;	char *ept, *eup, *up;	/*	 * If no buffer specified by the user, allocate one as necessary.	 * If a buffer is specified, the size has to be non-zero.  The path	 * is built from the end of the buffer backwards.	 */	if (pt) {		ptsize = 0;		if (!size) {			__os_set_errno(EINVAL);			return (NULL);		}		if (size == 1) {			__os_set_errno(ERANGE);			return (NULL);		}		ept = pt + size;	} else {		if ((ret =		    __os_malloc(NULL, ptsize = 1024 - 4, &pt)) != 0) {			__os_set_errno(ret);			return (NULL);		}		ept = pt + ptsize;	}	bpt = ept - 1;	*bpt = '\0';	/*	 * Allocate bytes (1024 - malloc space) for the string of "../"'s.	 * Should always be enough (it's 340 levels).  If it's not, allocate	 * as necessary.  Special case the first stat, it's ".", not "..".	 */	if ((ret = __os_malloc(NULL, upsize = 1024 - 4, &up)) != 0)		goto err;	eup = up + 1024;	bup = up;	up[0] = '.';	up[1] = '\0';	/* Save root values, so know when to stop. */	if (stat("/", &s))		goto err;	root_dev = s.st_dev;	root_ino = s.st_ino;	__os_set_errno(0);		/* XXX readdir has no error return. */	for (first = 1;; first = 0) {		/* Stat the current level. */		if (lstat(up, &s))			goto err;		/* Save current node values. */		ino = s.st_ino;		dev = s.st_dev;		/* Check for reaching root. */		if (root_dev == dev && root_ino == ino) {			*--bpt = PATH_SEPARATOR[0];			/*			 * It's unclear that it's a requirement to copy the			 * path to the beginning of the buffer, but it's always			 * been that way and stuff would probably break.			 */			bcopy(bpt, pt, ept - bpt);			__os_free(NULL, up);			return (pt);		}		/*		 * Build pointer to the parent directory, allocating memory		 * as necessary.  Max length is 3 for "../", the largest		 * possible component name, plus a trailing NULL.		 */		if (bup + 3  + MAXNAMLEN + 1 >= eup) {			if (__os_realloc(NULL, upsize *= 2, &up) != 0)				goto err;			bup = up;			eup = up + upsize;		}		*bup++ = '.';		*bup++ = '.';		*bup = '\0';		/* Open and stat parent directory. */		if (!(dir = opendir(up)) || fstat(dirfd(dir), &s))			goto err;		/* Add trailing slash for next directory. */		*bup++ = PATH_SEPARATOR[0];		/*		 * If it's a mount point, have to stat each element because		 * the inode number in the directory is for the entry in the		 * parent directory, not the inode number of the mounted file.		 */		save_errno = 0;		if (s.st_dev == dev) {			for (;;) {				if (!(dp = readdir(dir)))					goto notfound;				if (dp->d_fileno == ino)					break;			}		} else			for (;;) {				if (!(dp = readdir(dir)))					goto notfound;				if (ISDOT(dp))					continue;				bcopy(dp->d_name, bup, dp->d_namlen + 1);				/* Save the first error for later. */				if (lstat(up, &s)) {					if (save_errno == 0)						save_errno = __os_get_errno();					__os_set_errno(0);					continue;				}				if (s.st_dev == dev && s.st_ino == ino)					break;			}		/*		 * Check for length of the current name, preceding slash,		 * leading slash.		 */		if (bpt - pt < dp->d_namlen + (first ? 1 : 2)) {			size_t len, off;			if (!ptsize) {				__os_set_errno(ERANGE);				goto err;			}			off = bpt - pt;			len = ept - bpt;			if (__os_realloc(NULL, ptsize *= 2, &pt) != 0)				goto err;			bpt = pt + off;			ept = pt + ptsize;			bcopy(bpt, ept - len, len);			bpt = ept - len;		}		if (!first)			*--bpt = PATH_SEPARATOR[0];		bpt -= dp->d_namlen;		bcopy(dp->d_name, bpt, dp->d_namlen);		(void)closedir(dir);		/* Truncate any file name. */		*bup = '\0';	}notfound:	/*	 * If readdir set errno, use it, not any saved error; otherwise,	 * didn't find the current directory in its parent directory, set	 * errno to ENOENT.	 */	if (__os_get_errno_ret_zero() == 0)		__os_set_errno(save_errno == 0 ? ENOENT : save_errno);	/* FALLTHROUGH */err:	if (ptsize)		__os_free(NULL, pt);	__os_free(NULL, up);	return (NULL);}