mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-16 10:00:12 +00:00
1823e76b95
* sysdeps/posix/getcwd.c: Correct last patch. Handle getcwd (NULL, != 0) correctly.
429 lines
9.6 KiB
C
429 lines
9.6 KiB
C
/* Copyright (C) 1991,92,93,94,95,96,97,98,99 Free Software Foundation, Inc.
|
||
This file is part of the GNU C Library.
|
||
|
||
The GNU C Library is free software; you can redistribute it and/or
|
||
modify it under the terms of the GNU Library General Public License as
|
||
published by the Free Software Foundation; either version 2 of the
|
||
License, or (at your option) any later version.
|
||
|
||
The GNU C Library is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||
Library General Public License for more details.
|
||
|
||
You should have received a copy of the GNU Library General Public
|
||
License along with the GNU C Library; see the file COPYING.LIB. If not,
|
||
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
||
Boston, MA 02111-1307, USA. */
|
||
|
||
/* Wants:
|
||
AC_STDC_HEADERS
|
||
AC_DIR_HEADER
|
||
AC_UNISTD_H
|
||
AC_MEMORY_H
|
||
AC_CONST
|
||
AC_ALLOCA
|
||
*/
|
||
|
||
/* AIX requires this to be the first thing in the file. */
|
||
#if defined _AIX && !defined __GNUC__
|
||
#pragma alloca
|
||
#endif
|
||
|
||
#ifdef HAVE_CONFIG_H
|
||
# include "config.h"
|
||
#endif
|
||
|
||
#include <errno.h>
|
||
#include <sys/types.h>
|
||
#include <sys/stat.h>
|
||
|
||
#ifdef STDC_HEADERS
|
||
# include <stddef.h>
|
||
#endif
|
||
|
||
#if !defined __GNU_LIBRARY__ && !defined STDC_HEADERS
|
||
extern int errno;
|
||
#endif
|
||
#ifndef __set_errno
|
||
# define __set_errno(val) errno = (val)
|
||
#endif
|
||
|
||
#ifndef NULL
|
||
# define NULL 0
|
||
#endif
|
||
|
||
#if defined USGr3 && !defined DIRENT
|
||
# define DIRENT
|
||
#endif /* USGr3 */
|
||
#if defined Xenix && !defined SYSNDIR
|
||
# define SYSNDIR
|
||
#endif /* Xenix */
|
||
|
||
#if defined POSIX || defined DIRENT || defined __GNU_LIBRARY__
|
||
# include <dirent.h>
|
||
# ifndef __GNU_LIBRARY__
|
||
# define D_NAMLEN(d) strlen((d)->d_name)
|
||
# else
|
||
# define HAVE_D_NAMLEN
|
||
# define D_NAMLEN(d) ((d)->d_namlen)
|
||
# endif
|
||
#else /* not POSIX or DIRENT */
|
||
# define dirent direct
|
||
# define D_NAMLEN(d) ((d)->d_namlen)
|
||
# define HAVE_D_NAMLEN
|
||
# if defined USG && !defined sgi
|
||
# if defined SYSNDIR
|
||
# include <sys/ndir.h>
|
||
# else /* Not SYSNDIR */
|
||
# include "ndir.h"
|
||
# endif /* SYSNDIR */
|
||
# else /* not USG */
|
||
# include <sys/dir.h>
|
||
# endif /* USG */
|
||
#endif /* POSIX or DIRENT or __GNU_LIBRARY__ */
|
||
|
||
#if defined HAVE_UNISTD_H || defined __GNU_LIBRARY__
|
||
# include <unistd.h>
|
||
#endif
|
||
|
||
#if defined STDC_HEADERS || defined __GNU_LIBRARY__ || defined POSIX
|
||
# include <stdlib.h>
|
||
# include <string.h>
|
||
# define ANSI_STRING
|
||
#else /* No standard headers. */
|
||
|
||
# ifdef USG
|
||
|
||
# include <string.h>
|
||
# ifdef NEED_MEMORY_H
|
||
# include <memory.h>
|
||
# endif
|
||
# define ANSI_STRING
|
||
|
||
# else /* Not USG. */
|
||
|
||
# ifdef NeXT
|
||
|
||
# include <string.h>
|
||
|
||
# else /* Not NeXT. */
|
||
|
||
# include <strings.h>
|
||
|
||
# ifndef bcmp
|
||
extern int bcmp ();
|
||
# endif
|
||
# ifndef bzero
|
||
extern void bzero ();
|
||
# endif
|
||
# ifndef bcopy
|
||
extern void bcopy ();
|
||
# endif
|
||
|
||
# endif /* NeXT. */
|
||
|
||
# endif /* USG. */
|
||
|
||
extern char *malloc (), *realloc ();
|
||
extern void free ();
|
||
|
||
#endif /* Standard headers. */
|
||
|
||
#ifndef ANSI_STRING
|
||
# define memcpy(d, s, n) bcopy((s), (d), (n))
|
||
# define memmove memcpy
|
||
#endif /* Not ANSI_STRING. */
|
||
|
||
#ifndef MAX
|
||
# define MAX(a, b) ((a) < (b) ? (b) : (a))
|
||
#endif
|
||
|
||
#ifdef _LIBC
|
||
# ifndef mempcpy
|
||
# define mempcpy __mempcpy
|
||
# endif
|
||
# define HAVE_MEMPCPY 1
|
||
#endif
|
||
|
||
#if !defined __alloca && !defined __GNU_LIBRARY__
|
||
|
||
# ifdef __GNUC__
|
||
# undef alloca
|
||
# define alloca(n) __builtin_alloca (n)
|
||
# else /* Not GCC. */
|
||
# if defined sparc || defined HAVE_ALLOCA_H
|
||
# include <alloca.h>
|
||
# else /* Not sparc or HAVE_ALLOCA_H. */
|
||
# ifndef _AIX
|
||
extern char *alloca ();
|
||
# endif /* Not _AIX. */
|
||
# endif /* sparc or HAVE_ALLOCA_H. */
|
||
# endif /* GCC. */
|
||
|
||
# define __alloca alloca
|
||
|
||
#endif
|
||
|
||
#if defined HAVE_LIMITS_H || defined STDC_HEADERS || defined __GNU_LIBRARY__
|
||
# include <limits.h>
|
||
#else
|
||
# include <sys/param.h>
|
||
#endif
|
||
|
||
#ifndef PATH_MAX
|
||
# ifdef MAXPATHLEN
|
||
# define PATH_MAX MAXPATHLEN
|
||
# else
|
||
# define PATH_MAX 1024
|
||
# endif
|
||
#endif
|
||
|
||
#if !defined STDC_HEADERS && !defined __GNU_LIBRARY__
|
||
# undef size_t
|
||
# define size_t unsigned int
|
||
#endif
|
||
|
||
#if !__STDC__ && !defined const
|
||
# define const
|
||
#endif
|
||
|
||
#ifndef __GNU_LIBRARY__
|
||
# define __lstat stat
|
||
#endif
|
||
|
||
#ifndef _LIBC
|
||
# define __getcwd getcwd
|
||
#endif
|
||
|
||
#ifndef GETCWD_RETURN_TYPE
|
||
# define GETCWD_RETURN_TYPE char *
|
||
#endif
|
||
|
||
/* Get the pathname of the current working directory, and put it in SIZE
|
||
bytes of BUF. Returns NULL if the directory couldn't be determined or
|
||
SIZE was too small. If successful, returns BUF. In GNU, if BUF is
|
||
NULL, an array is allocated with `malloc'; the array is SIZE bytes long,
|
||
unless SIZE <= 0, in which case it is as big as necessary. */
|
||
|
||
GETCWD_RETURN_TYPE
|
||
__getcwd (buf, size)
|
||
char *buf;
|
||
size_t size;
|
||
{
|
||
static const char dots[]
|
||
= "../../../../../../../../../../../../../../../../../../../../../../../\
|
||
../../../../../../../../../../../../../../../../../../../../../../../../../../\
|
||
../../../../../../../../../../../../../../../../../../../../../../../../../..";
|
||
const char *dotp = &dots[sizeof (dots)];
|
||
const char *dotlist = dots;
|
||
size_t dotsize = sizeof (dots) - 1;
|
||
dev_t rootdev, thisdev;
|
||
ino_t rootino, thisino;
|
||
char *path;
|
||
register char *pathp;
|
||
struct stat st;
|
||
int prev_errno = errno;
|
||
size_t allocated = size;
|
||
|
||
if (size == 0)
|
||
{
|
||
if (buf != NULL)
|
||
{
|
||
__set_errno (EINVAL);
|
||
return NULL;
|
||
}
|
||
|
||
allocated = PATH_MAX + 1;
|
||
}
|
||
|
||
if (buf != NULL)
|
||
path = buf;
|
||
else
|
||
{
|
||
path = malloc (allocated);
|
||
if (path == NULL)
|
||
return NULL;
|
||
}
|
||
|
||
pathp = path + allocated;
|
||
*--pathp = '\0';
|
||
|
||
if (__lstat (".", &st) < 0)
|
||
goto lose2;
|
||
thisdev = st.st_dev;
|
||
thisino = st.st_ino;
|
||
|
||
if (__lstat ("/", &st) < 0)
|
||
goto lose2;
|
||
rootdev = st.st_dev;
|
||
rootino = st.st_ino;
|
||
|
||
while (!(thisdev == rootdev && thisino == rootino))
|
||
{
|
||
register DIR *dirstream;
|
||
struct dirent *d;
|
||
dev_t dotdev;
|
||
ino_t dotino;
|
||
char mount_point;
|
||
|
||
/* Look at the parent directory. */
|
||
if (dotp == dotlist)
|
||
{
|
||
/* My, what a deep directory tree you have, Grandma. */
|
||
char *new;
|
||
if (dotlist == dots)
|
||
{
|
||
new = malloc (dotsize * 2 + 1);
|
||
if (new == NULL)
|
||
goto lose;
|
||
#ifdef HAVE_MEMPCPY
|
||
dotp = mempcpy (new, dots, dotsize);
|
||
#else
|
||
memcpy (new, dots, dotsize);
|
||
dotp = &new[dotsize];
|
||
#endif
|
||
}
|
||
else
|
||
{
|
||
new = realloc ((__ptr_t) dotlist, dotsize * 2 + 1);
|
||
if (new == NULL)
|
||
goto lose;
|
||
dotp = &new[dotsize];
|
||
}
|
||
#ifdef HAVE_MEMPCPY
|
||
*((char *) mempcpy ((char *) dotp, new, dotsize)) = '\0';
|
||
dotsize *= 2;
|
||
#else
|
||
memcpy ((char *) dotp, new, dotsize);
|
||
dotsize *= 2;
|
||
new[dotsize] = '\0';
|
||
#endif
|
||
dotlist = new;
|
||
}
|
||
|
||
dotp -= 3;
|
||
|
||
/* Figure out if this directory is a mount point. */
|
||
if (__lstat (dotp, &st) < 0)
|
||
goto lose;
|
||
dotdev = st.st_dev;
|
||
dotino = st.st_ino;
|
||
mount_point = dotdev != thisdev;
|
||
|
||
/* Search for the last directory. */
|
||
dirstream = __opendir (dotp);
|
||
if (dirstream == NULL)
|
||
goto lose;
|
||
/* Clear errno to distinguish EOF from error if readdir returns
|
||
NULL. */
|
||
__set_errno (0);
|
||
while ((d = __readdir (dirstream)) != NULL)
|
||
{
|
||
if (d->d_name[0] == '.' &&
|
||
(d->d_name[1] == '\0' ||
|
||
(d->d_name[1] == '.' && d->d_name[2] == '\0')))
|
||
continue;
|
||
if (mount_point || (ino_t) d->d_ino == thisino)
|
||
{
|
||
char name[dotlist + dotsize - dotp + 1 + _D_ALLOC_NAMLEN (d)];
|
||
#ifdef HAVE_MEMPCPY
|
||
char *tmp = mempcpy (name, dotp, dotlist + dotsize - dotp);
|
||
*tmp++ = '/';
|
||
strcpy (tmp, d->d_name);
|
||
#else
|
||
memcpy (name, dotp, dotlist + dotsize - dotp);
|
||
name[dotlist + dotsize - dotp] = '/';
|
||
strcpy (&name[dotlist + dotsize - dotp + 1], d->d_name);
|
||
#endif
|
||
/* We don't fail here if we cannot stat() a directory entry.
|
||
This can happen when (network) filesystems fail. If this
|
||
entry is in fact the one we are looking for we will find
|
||
out soon as we reach the end of the directory without
|
||
having found anything. */
|
||
if (__lstat (name, &st) >= 0
|
||
&& st.st_dev == thisdev && st.st_ino == thisino)
|
||
break;
|
||
}
|
||
}
|
||
if (d == NULL)
|
||
{
|
||
int save = errno;
|
||
(void) __closedir (dirstream);
|
||
if (save == 0)
|
||
/* EOF on dirstream, which means that the current directory
|
||
has been removed. */
|
||
save = ENOENT;
|
||
__set_errno (save);
|
||
goto lose;
|
||
}
|
||
else
|
||
{
|
||
size_t namlen = _D_EXACT_NAMLEN (d);
|
||
|
||
if ((size_t) (pathp - path) <= namlen)
|
||
{
|
||
if (size != 0)
|
||
{
|
||
(void) __closedir (dirstream);
|
||
__set_errno (ERANGE);
|
||
goto lose;
|
||
}
|
||
else
|
||
{
|
||
char *tmp;
|
||
size_t oldsize = allocated;
|
||
|
||
allocated = 2 * MAX (allocated, namlen);
|
||
tmp = realloc (path, allocated);
|
||
if (tmp == NULL)
|
||
{
|
||
(void) __closedir (dirstream);
|
||
__set_errno (ENOMEM);/* closedir might have changed it.*/
|
||
goto lose;
|
||
}
|
||
|
||
/* Move current contents up to the end of the buffer.
|
||
This is guaranteed to be non-overlapping. */
|
||
pathp = memcpy (tmp + allocated - (path + oldsize - pathp),
|
||
tmp + (pathp - path),
|
||
path + oldsize - pathp);
|
||
path = tmp;
|
||
}
|
||
}
|
||
pathp -= namlen;
|
||
(void) memcpy (pathp, d->d_name, namlen);
|
||
*--pathp = '/';
|
||
(void) __closedir (dirstream);
|
||
}
|
||
|
||
thisdev = dotdev;
|
||
thisino = dotino;
|
||
}
|
||
|
||
if (pathp == &path[allocated - 1])
|
||
*--pathp = '/';
|
||
|
||
if (dotlist != dots)
|
||
free ((__ptr_t) dotlist);
|
||
|
||
memmove (path, pathp, path + allocated - pathp);
|
||
|
||
/* Restore errno on successful return. */
|
||
__set_errno (prev_errno);
|
||
|
||
return path;
|
||
|
||
lose:
|
||
if (dotlist != dots)
|
||
free ((__ptr_t) dotlist);
|
||
lose2:
|
||
if (buf == NULL)
|
||
free (path);
|
||
return NULL;
|
||
}
|
||
|
||
#if defined _LIBC && !defined __getcwd
|
||
weak_alias (__getcwd, getcwd)
|
||
#endif
|