Squashfs: add a decompressor framework

This adds a decompressor framework which allows multiple compression
algorithms to be cleanly supported.

Also update zlib wrapper and other code to use the new framework.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>

1 files changed, 55 insertions, 0 deletions

diff --git a/fs/squashfs/decompressor.h b/fs/squashfs/decompressor.h
new file mode 100644
index 000000000000..7425f80783f6
--- /dev/null
+++ b/fs/squashfs/decompressor.h
@@ -0,0 +1,55 @@
+#ifndef DECOMPRESSOR_H
+#define DECOMPRESSOR_H
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+ * Phillip Lougher <phillip@lougher.demon.co.uk>
+ *
+ * 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,
+ * 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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * decompressor.h
+ */
+
+struct squashfs_decompressor {
+	void	*(*init)(struct squashfs_sb_info *);
+	void	(*free)(void *);
+	int	(*decompress)(struct squashfs_sb_info *, void **,
+		struct buffer_head **, int, int, int, int, int);
+	int	id;
+	char	*name;
+	int	supported;
+};
+
+static inline void *squashfs_decompressor_init(struct squashfs_sb_info *msblk)
+{
+	return msblk->decompressor->init(msblk);
+}
+
+static inline void squashfs_decompressor_free(struct squashfs_sb_info *msblk,
+	void *s)
+{
+	if (msblk->decompressor)
+		msblk->decompressor->free(s);
+}
+
+static inline int squashfs_decompress(struct squashfs_sb_info *msblk,
+	void **buffer, struct buffer_head **bh, int b, int offset, int length,
+	int srclength, int pages)
+{
+	return msblk->decompressor->decompress(msblk, buffer, bh, b, offset,
+		length, srclength, pages);
+}
+#endif