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Diffstat (limited to 'REORG.TODO/sysdeps/unix/sysv/linux/getcwd.c')
-rw-r--r--REORG.TODO/sysdeps/unix/sysv/linux/getcwd.c135
1 files changed, 135 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/getcwd.c b/REORG.TODO/sysdeps/unix/sysv/linux/getcwd.c
new file mode 100644
index 0000000000..3b556fd450
--- /dev/null
+++ b/REORG.TODO/sysdeps/unix/sysv/linux/getcwd.c
@@ -0,0 +1,135 @@
+/* Determine current working directory. Linux version.
+ Copyright (C) 1997-2017 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 Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <assert.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/param.h>
+
+#include <sysdep.h>
+#include <sys/syscall.h>
+
+
+/* If we compile the file for use in ld.so we don't need the feature
+ that getcwd() allocates the buffers itself. */
+#if IS_IN (rtld)
+# define NO_ALLOCATION 1
+#endif
+
+
+/* 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) internal_function;
+
+char *
+__getcwd (char *buf, size_t size)
+{
+ char *path;
+ char *result;
+
+#ifndef NO_ALLOCATION
+ size_t alloc_size = size;
+ if (size == 0)
+ {
+ if (buf != NULL)
+ {
+ __set_errno (EINVAL);
+ return NULL;
+ }
+
+ alloc_size = MAX (PATH_MAX, __getpagesize ());
+ }
+
+ if (buf == NULL)
+ {
+ path = malloc (alloc_size);
+ if (path == NULL)
+ return NULL;
+ }
+ else
+#else
+# define alloc_size size
+#endif
+ path = buf;
+
+ int retval;
+
+ retval = INLINE_SYSCALL (getcwd, 2, path, alloc_size);
+ if (retval >= 0)
+ {
+#ifndef NO_ALLOCATION
+ if (buf == NULL && size == 0)
+ /* Ensure that the buffer is only as large as necessary. */
+ buf = realloc (path, (size_t) retval);
+
+ if (buf == NULL)
+ /* Either buf was NULL all along, or `realloc' failed but
+ we still have the original string. */
+ buf = path;
+#endif
+
+ return buf;
+ }
+
+ /* The system call cannot handle paths longer than a page.
+ Neither can the magic symlink in /proc/self. Just use the
+ generic implementation right away. */
+ if (errno == ENAMETOOLONG)
+ {
+#ifndef NO_ALLOCATION
+ if (buf == NULL && size == 0)
+ {
+ free (path);
+ path = NULL;
+ }
+#endif
+
+ result = generic_getcwd (path, size);
+
+#ifndef NO_ALLOCATION
+ if (result == NULL && buf == NULL && size != 0)
+ free (path);
+#endif
+
+ return result;
+ }
+
+ /* It should never happen that the `getcwd' syscall failed because
+ the buffer is too small if we allocated the buffer ourselves
+ large enough. */
+ assert (errno != ERANGE || buf != NULL || size != 0);
+
+#ifndef NO_ALLOCATION
+ if (buf == NULL)
+ free (path);
+#endif
+
+ return NULL;
+}
+weak_alias (__getcwd, getcwd)
+
+/* Get the code for the generic version. */
+#define GETCWD_RETURN_TYPE static char * internal_function
+#define __getcwd generic_getcwd
+#include <sysdeps/posix/getcwd.c>