zlib: add gunzip() support

This commit adds some more files to use zlib from TF.

To use zlib, ->zalloc and ->zfree hooks are needed.  The implementation
depends on the system.  For user-space, the libc provides malloc() and
friends.  Unfortunately, ARM Trusted Firmware does not provide malloc()
or any concept of dynamic memory allocation.

I implemented very simple calloc() and free() for this.  Stupidly,
zfree() never frees memory, but it works enough for this.

The purpose of using zlib is to implement gunzip() - this function
takes compressed data from in_buf, then dumps the decompressed data
to oub_buf.  The work_buf is used for memory allocation during the
decompress.  Upon exit, it updates in_buf and out_buf.  If successful,
in_buf points to the end of input data, out_buf to the end of the
decompressed data.

To use this feature, you need to do:

 - include lib/zlib/zlib.mk from your platform.mk

 - add $(ZLIB_SOURCES) to your BL*_SOURCES

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/lib/zlib/zlib.mk b/lib/zlib/zlib.mk
new file mode 100644
index 000000000..98d4efaa8
--- /dev/null
+++ b/lib/zlib/zlib.mk
@@ -0,0 +1,25 @@
+#
+# Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+
+ZLIB_PATH	:=	lib/zlib
+
+# Imported from zlib 1.2.11 (do not modify them)
+ZLIB_SOURCES	:=	$(addprefix $(ZLIB_PATH)/,	\
+					adler32.c	\
+					crc32.c		\
+					inffast.c	\
+					inflate.c	\
+					inftrees.c	\
+					zutil.c)
+
+# Implemented for TF
+ZLIB_SOURCES	+=	$(addprefix $(ZLIB_PATH)/,	\
+					tf_gunzip.c)
+
+INCLUDES	+=	-Iinclude/lib/zlib
+
+# REVISIT: the following flags need not be given globally
+TF_CFLAGS	+=	-DZ_SOLO -DDEF_WBITS=31