r4242: added support for storing xattrs in a tdb. This allows all advanced NT

attributes (streams, EAs, NT ACLs, timestamps etc) to be used on
filesystems that don't support xattrs. It also allows for large
streams, although they are very inefficient.

I won't enable this by default, as I really wrote it as a way of
testing large stream support while still using ext3, but perhaps with
a bit more work this could be generally usable.

To enable this use:

   posix:eadb = /home/test/myeas.tdb
(This used to be commit 0c927d912cb65754351189d3a0442004a14aa5c6)

1 files changed, 134 insertions, 0 deletions

diff --git a/source4/ntvfs/posix/xattr_system.c b/source4/ntvfs/posix/xattr_system.c
new file mode 100644
index 0000000000..c86ee0bd87
--- /dev/null
+++ b/source4/ntvfs/posix/xattr_system.c
@@ -0,0 +1,134 @@
+/* 
+   Unix SMB/CIFS implementation.
+
+   POSIX NTVFS backend - xattr support using filesystem xattrs
+
+   Copyright (C) Andrew Tridgell 2004
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   
+   This program 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 General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+#include "system/filesys.h"
+#include "vfs_posix.h"
+
+/*
+  pull a xattr as a blob, from either a file or a file descriptor
+*/
+NTSTATUS pull_xattr_blob_system(struct pvfs_state *pvfs,
+				TALLOC_CTX *mem_ctx,
+				const char *attr_name, 
+				const char *fname, 
+				int fd, 
+				size_t estimated_size,
+				DATA_BLOB *blob)
+{
+#if HAVE_XATTR_SUPPORT
+	int ret;
+
+	*blob = data_blob_talloc(mem_ctx, NULL, estimated_size);
+	if (blob->data == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+again:
+	if (fd != -1) {
+		ret = fgetxattr(fd, attr_name, blob->data, estimated_size);
+	} else {
+		ret = getxattr(fname, attr_name, blob->data, estimated_size);
+	}
+	if (ret == -1 && errno == ERANGE) {
+		estimated_size *= 2;
+		blob->data = talloc_realloc(mem_ctx, blob->data, estimated_size);
+		if (blob->data == NULL) {
+			return NT_STATUS_NO_MEMORY;
+		}
+		blob->length = estimated_size;
+		goto again;
+	}
+
+	if (ret == -1) {
+		data_blob_free(blob);
+		return pvfs_map_errno(pvfs, errno);
+	}
+
+	blob->length = ret;
+
+	return NT_STATUS_OK;
+#else
+	return NT_STATUS_NOT_SUPPORTED;
+#endif
+}
+
+/*
+  push a xattr as a blob, from either a file or a file descriptor
+*/
+NTSTATUS push_xattr_blob_system(struct pvfs_state *pvfs,
+				const char *attr_name, 
+				const char *fname, 
+				int fd, 
+				const DATA_BLOB *blob)
+{
+#if HAVE_XATTR_SUPPORT
+	int ret;
+
+	if (fd != -1) {
+		ret = fsetxattr(fd, attr_name, blob->data, blob->length, 0);
+	} else {
+		ret = setxattr(fname, attr_name, blob->data, blob->length, 0);
+	}
+	if (ret == -1) {
+		return pvfs_map_errno(pvfs, errno);
+	}
+
+	return NT_STATUS_OK;
+#else
+	return NT_STATUS_NOT_SUPPORTED;
+#endif
+}
+
+
+/*
+  delete a xattr
+*/
+NTSTATUS delete_xattr_system(struct pvfs_state *pvfs, const char *attr_name, 
+			     const char *fname, int fd)
+{
+#if HAVE_XATTR_SUPPORT
+	int ret;
+
+	if (fd != -1) {
+		ret = fremovexattr(fd, attr_name);
+	} else {
+		ret = removexattr(fname, attr_name);
+	}
+	if (ret == -1) {
+		return pvfs_map_errno(pvfs, errno);
+	}
+
+	return NT_STATUS_OK;
+#else
+	return NT_STATUS_NOT_SUPPORTED;
+#endif
+}
+
+/*
+  unlink a file - cleanup any xattrs
+*/
+NTSTATUS unlink_xattr_system(struct pvfs_state *pvfs, const char *fname)
+{
+	/* nothing needs to be done for filesystem based xattrs */
+	return NT_STATUS_OK;
+}