File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/powerpc/boot/gunzip_util.h b/arch/powerpc/boot/gunzip_util.h
new file mode 100644
index 0000000..b3dfa6e
--- /dev/null
+++ b/arch/powerpc/boot/gunzip_util.h
@@ -0,0 +1,45 @@
+/*
+ * Decompression convenience functions
+ *
+ * Copyright 2007 David Gibson, IBM Corporation.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+#ifndef _PPC_BOOT_GUNZIP_UTIL_H_
+#define _PPC_BOOT_GUNZIP_UTIL_H_
+
+#include "zlib.h"
+
+/*
+ * These functions are designed to make life easy for decompressing
+ * kernel images, initrd images or any other gzip compressed image,
+ * particularly if its useful to decompress part of the image (e.g. to
+ * examine headers) before decompressing the remainder.
+ *
+ * To use:
+ * - declare a gunzip_state structure
+ * - use gunzip_start() to initialize the state, associating it
+ * with a stream of compressed data
+ * - use gunzip_partial(), gunzip_exactly() and gunzip_discard()
+ * in any combination to extract pieces of data from the stream
+ * - Finally use gunzip_finish() to extract the tail of the
+ * compressed stream and wind up zlib
+ */
+
+/* scratch space for gunzip; 46912 is from zlib_inflate_workspacesize() */
+#define GUNZIP_SCRATCH_SIZE 46912
+
+struct gunzip_state {
+ z_stream s;
+ char scratch[46912];
+};
+
+void gunzip_start(struct gunzip_state *state, void *src, int srclen);
+int gunzip_partial(struct gunzip_state *state, void *dst, int dstlen);
+void gunzip_exactly(struct gunzip_state *state, void *dst, int len);
+void gunzip_discard(struct gunzip_state *state, int len);
+int gunzip_finish(struct gunzip_state *state, void *dst, int len);
+
+#endif /* _PPC_BOOT_GUNZIP_UTIL_H_ */