/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/* Copyright (c) 1988 AT&T */
/* All Rights Reserved */
/*
* _xftw - file tree walk the uses expanded stat structure
*
* int _xftw(path, fn, depth) char *path; int (*fn)(); int depth;
*
* Given a path name, _xftw starts from the file given by that path
* name and visits each file and directory in the tree beneath
* that file. If a single file has multiple links within the
* structure, it will be visited once for each such link.
* For each object visited, fn is called with three arguments.
* (*fn) (pathname, statp, ftwflag)
* The first contains the path name of the object, the second
* contains a pointer to a stat buffer which will usually hold
* appropriate information for the object and the third will
* contain an integer value giving additional information about
*
* FTW_F The object is a file for which stat was
* successful. It does not guarantee that the
* file can actually be read.
*
* FTW_D The object is a directory for which stat and
* open for read were both successful.
*
* FTW_DNR The object is a directory for which stat
* succeeded, but which cannot be read. Because
* the directory cannot be read, fn will not be
* called for any descendants of this directory.
*
* FTW_NS Stat failed on the object because of lack of
* appropriate permission. This indication will
* be given for example for each file in a
* directory with read but no execute permission.
* Because stat failed, it is not possible to
* determine whether this object is a file or a
* directory. The stat buffer passed to fn will
* contain garbage. Stat failure for any reason
* other than lack of permission will be
* considered an error and will cause _xftw to stop
* and return -1 to its caller.
*
* If fn returns nonzero, _xftw stops and returns the same value
* to its caller. If _xftw gets into other trouble along the way,
* it returns -1 and leaves an indication of the cause in errno.
*
* The third argument to _xftw does not limit the depth to which
* _xftw will go. Rather, it limits the depth to which _xftw will
* go before it starts recycling file descriptors. In general,
* it is necessary to use a file descriptor for each level of the
* tree, but they can be recycled for deep trees by saving the
* position, closing, re-opening, and seeking. It is possible
* to start recycling file descriptors by sensing when we have
* run out, but in general this will not be terribly useful if
* fn expects to be able to open files. We could also figure out
* how many file descriptors are available and guarantee a certain
* number to fn, but we would not know how many to guarantee,
* and we do not want to impose the extra overhead on a caller who
* knows how many are available without having to figure it out.
*
* It is possible for _xftw to die with a memory fault in the event
* of a file system so deeply nested that the stack overflows.
*/
/*
* this interface uses the expanded stat structure and therefore
* must have EFT enabled.
*/
#ifdef _STYPES
#undef _STYPES
#endif
#include <sys/feature_tests.h>
#if !defined(_LP64) && _FILE_OFFSET_BITS == 64
#define lstat64 _lstat64
#define readdir64 _readdir64
#define stat64 _stat64
#else
#define lstat _lstat
#define readdir _readdir
#define stat _stat
#endif /* !_LP64 && _FILE_OFFSET_BITS == 64 */
#define closedir _closedir
#define opendir _opendir
#define seekdir _seekdir
#define telldir _telldir
#include "lint.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <dirent.h>
#include <errno.h>
#include <ftw.h>
#include <string.h>
#include <stdlib.h>
#include <alloca.h>
int
_xftw(int ver, const char *path,
int (*fn)(const char *, const struct stat *, int), int depth)
{
size_t n;
int rc;
int save_errno;
DIR *dirp;
char *subpath;
struct stat sb;
struct dirent *direntp;
/*
* Try to get file status.
* If unsuccessful, errno will say why.
* It's ok to have a symbolic link that points to
* non-existing file. In this case, pass FTW_NS
* to a function instead of aborting _xftw() right away.
*/
if (stat(path, &sb) < 0) {
#ifdef S_IFLNK
save_errno = errno;
if ((lstat(path, &sb) != -1) &&
((sb.st_mode & S_IFMT) == S_IFLNK)) {
errno = save_errno;
return (*fn)(path, &sb, FTW_NS);
} else {
errno = save_errno;
}
#endif
return (errno == EACCES? (*fn)(path, &sb, FTW_NS): -1);
}
/*
* The stat succeeded, so we know the object exists.
* If not a directory, call the user function and return.
*/
if ((sb.st_mode & S_IFMT) != S_IFDIR)
return ((*fn)(path, &sb, FTW_F));
/*
* The object was a directory.
*
* Open a file to read the directory
*/
dirp = opendir(path);
/*
* Call the user function, telling it whether
* the directory can be read. If it can't be read
* call the user function or indicate an error,
* depending on the reason it couldn't be read.
*/
if (dirp == NULL)
return (errno == EACCES? (*fn)(path, &sb, FTW_DNR): -1);
/* We could read the directory. Call user function. */
rc = (*fn)(path, &sb, FTW_D);
if (rc != 0) {
(void) closedir(dirp);
return (rc);
}
/* Create a prefix to which we will append component names */
n = strlen(path);
subpath = alloca(n + MAXNAMELEN + 2);
(void) strcpy(subpath, path);
if (subpath[0] != '\0' && subpath[n-1] != '/')
subpath[n++] = '/';
/*
* Read the directory one component at a time.
* We must ignore "." and "..", but other than that,
* just create a path name and call self to check it out.
*/
while (direntp = readdir(dirp)) {
long here;
if (strcmp(direntp->d_name, ".") == 0 ||
strcmp(direntp->d_name, "..") == 0)
continue;
/* Append component name to the working path */
(void) strlcpy(&subpath[n], direntp->d_name, MAXNAMELEN);
/*
* If we are about to exceed our depth,
* remember where we are and close a file.
*/
if (depth <= 1) {
here = telldir(dirp);
if (closedir(dirp) < 0)
return (-1);
}
/*
* Do a recursive call to process the file.
* (watch this, sports fans)
*/
rc = _xftw(ver, subpath, fn, depth-1);
if (rc != 0) {
if (depth > 1)
(void) closedir(dirp);
return (rc);
}
/*
* If we closed the file, try to reopen it.
*/
if (depth <= 1) {
dirp = opendir(path);
if (dirp == NULL)
return (-1);
seekdir(dirp, here);
}
}
(void) closedir(dirp);
return (0);
}