summaryrefslogtreecommitdiff
path: root/sysdeps/mach/hurd/getcwd.c
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/mach/hurd/getcwd.c')
-rw-r--r--sysdeps/mach/hurd/getcwd.c250
1 files changed, 250 insertions, 0 deletions
diff --git a/sysdeps/mach/hurd/getcwd.c b/sysdeps/mach/hurd/getcwd.c
new file mode 100644
index 0000000000..c0d9bcd567
--- /dev/null
+++ b/sysdeps/mach/hurd/getcwd.c
@@ -0,0 +1,250 @@
+/* Copyright (C) 1991, 1992, 1993, 1994 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., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <hurd.h>
+#include <hurd/port.h>
+#include <dirent.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <fcntl.h>
+
+
+/* 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. */
+
+char *
+getcwd (char *buf, size_t size)
+{
+ error_t err;
+ dev_t rootdev, thisdev;
+ ino_t rootino, thisino;
+ char *file_name;
+ register char *file_namep;
+ struct stat st;
+ file_t parent;
+ char *dirbuf = NULL;
+ unsigned int dirbufsize = 0;
+ file_t crdir;
+ struct hurd_userlink crdir_ulink;
+
+ inline void cleanup (void)
+ {
+ _hurd_port_free (&_hurd_ports[INIT_PORT_CRDIR], &crdir_ulink, crdir);
+ __mach_port_deallocate (__mach_task_self (), parent);
+
+ if (dirbuf != NULL)
+ __vm_deallocate (__mach_task_self (),
+ (vm_address_t) dirbuf, dirbufsize);
+ }
+
+
+ if (size == 0)
+ {
+ if (buf != NULL)
+ {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ size = FILENAME_MAX * 4 + 1; /* Good starting guess. */
+ }
+
+ if (buf != NULL)
+ file_name = buf;
+ else
+ {
+ file_name = malloc (size);
+ if (file_name == NULL)
+ return NULL;
+ }
+
+ file_namep = file_name + size;
+ *--file_namep = '\0';
+
+ /* Get a port to our root directory and stat it. */
+
+ crdir = _hurd_port_get (&_hurd_ports[INIT_PORT_CRDIR], &crdir_ulink);
+ if (err = __io_stat (crdir, &st))
+ {
+ _hurd_port_free (&_hurd_ports[INIT_PORT_CRDIR], &crdir_ulink, crdir);
+ return __hurd_fail (err), NULL;
+ }
+ rootdev = st.st_dev;
+ rootino = st.st_ino;
+
+ /* Get a port to our current working directory and stat it. */
+
+ if (err = __USEPORT (CWDIR, __mach_port_mod_refs (__mach_task_self (),
+ (parent = port),
+ MACH_PORT_RIGHT_SEND,
+ 1)))
+ {
+ _hurd_port_free (&_hurd_ports[INIT_PORT_CRDIR], &crdir_ulink, crdir);
+ return __hurd_fail (err), NULL;
+ }
+ if (err = __io_stat (parent, &st))
+ {
+ cleanup ();
+ return __hurd_fail (err), NULL;
+ }
+
+ thisdev = st.st_dev;
+ thisino = st.st_ino;
+
+ while (!(thisdev == rootdev && thisino == rootino))
+ {
+ /* PARENT is a port to the directory we are currently on;
+ THISDEV and THISINO are its device and node numbers.
+ Look in its parent (..) for a file with the same numbers. */
+
+ struct dirent *d;
+ dev_t dotdev;
+ ino_t dotino;
+ int mount_point;
+ file_t newp;
+ char *dirdata;
+ unsigned int dirdatasize;
+ int direntry, nentries;
+
+ /* Look at the parent directory. */
+ if (err = __hurd_file_name_lookup (crdir, parent, "..", O_READ, 0, &newp))
+ goto lose;
+ __mach_port_deallocate (__mach_task_self (), parent);
+ parent = newp;
+
+ /* Figure out if this directory is a mount point. */
+ if (err = __io_stat (parent, &st))
+ goto lose;
+ dotdev = st.st_dev;
+ dotino = st.st_ino;
+ mount_point = dotdev != thisdev;
+
+ /* Search for the last directory. */
+ direntry = 0;
+ dirdata = dirbuf;
+ dirdatasize = dirbufsize;
+ while (!(err = __dir_readdir (parent, &dirdata, &dirdatasize,
+ direntry, -1, 0, &nentries)) &&
+ nentries != 0)
+ {
+ /* We have a block of directory entries. */
+
+ unsigned int offset;
+
+ direntry += nentries;
+
+ if (dirdata != dirbuf)
+ {
+ /* The data was passed out of line, so our old buffer is no
+ longer useful. Deallocate the old buffer and reset our
+ information for the new buffer. */
+ __vm_deallocate (__mach_task_self (),
+ (vm_address_t) dirbuf, dirbufsize);
+ dirbuf = dirdata;
+ dirbufsize = round_page (dirdatasize);
+ }
+
+ /* Iterate over the returned directory entries, looking for one
+ whose file number is THISINO. */
+
+ offset = 0;
+ while (offset < dirdatasize)
+ {
+ d = (struct dirent *) &dirdata[offset];
+ offset += d->d_reclen;
+
+ /* Ignore `.' and `..'. */
+ if (d->d_name[0] == '.' &&
+ (d->d_namlen == 1 ||
+ (d->d_namlen == 2 && d->d_name[1] == '.')))
+ continue;
+
+ if (mount_point || d->d_ino == thisino)
+ {
+ file_t try;
+ if (err = __hurd_file_name_lookup (crdir, parent, d->d_name,
+ O_NOLINK, 0, &try))
+ goto lose;
+ err = __io_stat (try, &st);
+ __mach_port_deallocate (__mach_task_self (), try);
+ if (err)
+ goto lose;
+ if (st.st_dev == thisdev && st.st_ino == thisino)
+ break;
+ }
+ }
+ }
+
+ if (err)
+ goto lose;
+ else
+ {
+ /* Prepend the directory name just discovered. */
+
+ if (file_namep - file_name < d->d_namlen + 1)
+ {
+ if (buf != NULL)
+ {
+ errno = ERANGE;
+ return NULL;
+ }
+ else
+ {
+ size *= 2;
+ buf = realloc (file_name, size);
+ if (buf == NULL)
+ {
+ free (file_name);
+ return NULL;
+ }
+ file_namep = &buf[file_namep - file_name];
+ file_name = buf;
+ }
+ }
+ file_namep -= d->d_namlen;
+ (void) memcpy (file_namep, d->d_name, d->d_namlen);
+ *--file_namep = '/';
+ }
+
+ /* The next iteration will find the name of the directory we
+ just searched through. */
+ thisdev = dotdev;
+ thisino = dotino;
+ }
+
+ if (file_namep == &file_name[size - 1])
+ /* We found nothing and got all the way to the root.
+ So the root is our current directory. */
+ *--file_namep = '/';
+
+ memmove (file_name, file_namep, file_name + size - file_namep);
+ cleanup ();
+ return file_name;
+
+ lose:
+ cleanup ();
+ return NULL;
+}