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Diffstat (limited to 'sysdeps/unix/sysv/linux/getcwd.c')
-rw-r--r--sysdeps/unix/sysv/linux/getcwd.c94
1 files changed, 94 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/getcwd.c b/sysdeps/unix/sysv/linux/getcwd.c
new file mode 100644
index 0000000000..eea0b469e1
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/getcwd.c
@@ -0,0 +1,94 @@
+/* Determine current working directory. Linux version.
+ Copyright (C) 1997 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+ 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. */
+
+#include <errno.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+/* #define NDEBUG 1 */
+#include <assert.h>
+
+/* The "proc" filesystem provides an easy method to retrieve the value.
+ For each process, the corresponding directory contains a symbolic link
+ named `cwd'. Reading the content of this link immediate gives us the
+ information. But we have to take care for systems which do not have
+ the proc filesystem mounted. Use the POSIX implementation in this case. */
+static char *generic_getcwd (char *buf, size_t size);
+
+char *
+__getcwd (char *buf, size_t size)
+{
+ int save_errno;
+ char *path;
+ int n;
+ char *result;
+
+ if (size == 0)
+ {
+ if (buf != NULL)
+ {
+ __set_errno (EINVAL);
+ return NULL;
+ }
+
+ size = PATH_MAX + 1;
+ }
+
+ if (buf != NULL)
+ path = buf;
+ else
+ {
+ path = malloc (size);
+ if (path == NULL)
+ return NULL;
+ }
+
+ save_errno = errno;
+ n = __readlink ("/proc/self/cwd", path, size);
+ if (n != -1)
+ {
+ if (n >= size)
+ {
+ /* This should never happen when we allocate the buffer here. */
+ assert (buf == NULL);
+ __set_errno (ERANGE);
+ return NULL;
+ }
+ path[n] = '\0';
+ return buf ?: (char *) realloc (path, (size_t) n + 1);
+ }
+
+ /* Something went wrong. Restore the error number and use the generic
+ version. */
+ __set_errno (save_errno);
+ result = generic_getcwd (path, size);
+
+ if (result == NULL && buf == NULL)
+ free (path);
+
+ return result;
+}
+weak_alias (__getcwd, getcwd)
+
+/* Get the code for the generic version. */
+#define GETCWD_STORAGE_CLASS static
+#define __getcwd generic_getcwd
+#include <sysdeps/posix/getcwd.c>