getcwd.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* 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"
#include "_synonyms.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <dirent.h>
#include <limits.h>
#include <stdlib.h>
#include <strings.h>
#include "_rtld.h"
#include "msg.h"
#ifndef EXPAND_RELATIVE
static struct stat status;
/*
* Included here (instead of using libc's) to reduce the number of stat calls.
*/
static DIR *
_opendir(const char *file)
{
DIR *dirp;
int fd;
if ((fd = open(file, (O_RDONLY | O_NDELAY), 0)) < 0)
return (0);
if ((fstat(fd, &status) < 0) ||
((status.st_mode & S_IFMT) != S_IFDIR) ||
((dirp = (DIR *)malloc(sizeof (DIR) + DIRBUF)) == NULL)) {
(void) close(fd);
return (0);
}
dirp->dd_buf = (char *)dirp + sizeof (DIR);
dirp->dd_fd = fd;
dirp->dd_loc = dirp->dd_size = 0;
return (dirp);
}
static struct dirent *
_readdir(DIR *dirp)
{
struct dirent *denp;
int saveloc = 0;
if (dirp->dd_size != 0) {
/* LINTED */
denp = (struct dirent *)&dirp->dd_buf[dirp->dd_loc];
saveloc = dirp->dd_loc;
dirp->dd_loc += denp->d_reclen;
}
if (dirp->dd_loc >= dirp->dd_size)
dirp->dd_loc = dirp->dd_size = 0;
if ((dirp->dd_size == 0) &&
((dirp->dd_size = getdents(dirp->dd_fd,
/* LINTED */
(struct dirent *)dirp->dd_buf, DIRBUF)) <= 0)) {
if (dirp->dd_size == 0)
dirp->dd_loc = saveloc;
return (0);
}
/* LINTED */
denp = (struct dirent *)&dirp->dd_buf[dirp->dd_loc];
return (denp);
}
static int
_closedir(DIR * dirp)
{
int fd = dirp->dd_fd;
free((char *)dirp);
return (close(fd));
}
/*
* Simplified getcwd(3C), stolen from raf's proc(1) pwdx.
*/
char *
getcwd(char *path, size_t pathsz)
{
char _path[PATH_MAX], cwd[PATH_MAX];
size_t cwdsz;
ino_t cino;
dev_t cdev;
_path[--pathsz] = '\0';
/*
* Stat the present working directory to establish the initial device
* and inode pair.
*/
(void) strcpy(cwd, MSG_ORIG(MSG_FMT_CWD));
cwdsz = MSG_FMT_CWD_SIZE;
if (stat(cwd, &status) == -1)
return (NULL);
/* LINTED */
while (1) {
DIR *dirp;
struct dirent *denp;
size_t len;
cino = status.st_ino;
cdev = status.st_dev;
/*
* Open parent directory
*/
(void) strcpy(&cwd[cwdsz], MSG_ORIG(MSG_FMT_PARENT));
cwdsz += MSG_FMT_PARENT_SIZE;
if ((dirp = _opendir(cwd)) == 0)
return (NULL);
/*
* Find subdirectory of parent that matches current directory.
*/
if (cdev == status.st_dev) {
if (cino == status.st_ino) {
/*
* At root, return the pathname we've
* established.
*/
(void) _closedir(dirp);
(void) strcpy(path, &_path[pathsz]);
return (path);
}
do {
if ((denp = _readdir(dirp)) == NULL) {
(void) _closedir(dirp);
return (NULL);
}
} while (denp->d_ino != cino);
} else {
/*
* The parent director is a different filesystem, so
* determine filenames of subdirectories and stat.
*/
struct stat _status;
cwd[cwdsz] = '/';
/* LINTED */
while (1) {
if ((denp = _readdir(dirp)) == NULL) {
(void) _closedir(dirp);
return (NULL);
}
if (denp->d_name[0] == '.') {
if (denp->d_name[1] == '\0')
continue;
if (denp->d_name[1] == '.' &&
denp->d_name[2] == '\0')
continue;
}
(void) strcpy(&cwd[cwdsz + 1], denp->d_name);
/*
* Silently ignore non-stat'able entries.
*/
if (stat(cwd, &_status) == -1)
continue;
if ((_status.st_ino == cino) &&
(_status.st_dev == cdev))
break;
}
}
/*
* Copy name of current directory into pathname.
*/
if ((len = strlen(denp->d_name)) < pathsz) {
pathsz -= len;
(void) strncpy(&_path[pathsz], denp->d_name, len);
_path[--pathsz] = '/';
}
(void) _closedir(dirp);
}
return (NULL);
}
#endif
/*
* Take the given link-map file/pathname and prepend the current working
* directory.
*/
size_t
fullpath(Rt_map *lmp, const char *rpath)
{
char *name, _path[PATH_MAX];
/*
* If a resolved path isn't provided, establish one from the PATHNAME().
*/
if (rpath)
PATHNAME(lmp) = (char *)rpath;
else {
char *path;
name = path = (char *)PATHNAME(lmp);
if (path[0] != '/') {
/*
* If we can't determine the current directory (possible
* if too many files are open - EMFILE), or if the
* created path is too big, simply revert back to the
* initial pathname.
*/
if (getcwd(_path, (PATH_MAX - 2 - strlen(name))) !=
NULL) {
(void) strcat(_path, MSG_ORIG(MSG_STR_SLASH));
(void) strcat(_path, name);
path = _path;
}
}
/*
* See if the pathname can be reduced further.
*/
if (rtld_flags & RT_FL_EXECNAME) {
int size = PATH_MAX - 1;
if ((size = resolvepath(path, _path, size)) > 0) {
_path[size] = '\0';
path = _path;
}
}
/*
* If the pathname is different from the original, duplicate it
* so that it is available in a core file. If the duplication
* fails simply leave the original pathname alone.
*/
if ((name != path) && strcmp(name, path)) {
if ((PATHNAME(lmp) = strdup(path)) == 0)
PATHNAME(lmp) = name;
}
}
name = ORIGNAME(lmp) = PATHNAME(lmp);
/*
* Establish the directory name size - this also acts as a flag that the
* directory name has been computed.
*/
DIRSZ(lmp) = strrchr(name, '/') - name;
return (DIRSZ(lmp));
}