ar71xx: add library code for RLE decoding

It will be used for the MikroTik boards.

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@33337 3c298f89-4303-0410-b956-a3cf2f4a3e73

diff --git a/target/linux/ar71xx/config-3.3 b/target/linux/ar71xx/config-3.3
index f346613..3b3ace5 100644 (file)
--- a/target/linux/ar71xx/config-3.3
+++ b/target/linux/ar71xx/config-3.3
@@ -188,6 +188,7 @@ CONFIG_PCI_DOMAINS=y
 CONFIG_PERF_USE_VMALLOC=y
 CONFIG_PHYLIB=y
 # CONFIG_PREEMPT_RCU is not set
+# CONFIG_RLE_DECOMPRESS is not set
 CONFIG_RTL8306_PHY=y
 CONFIG_RTL8366RB_PHY=y
 CONFIG_RTL8366S_PHY=y

diff --git a/target/linux/ar71xx/patches-3.3/310-lib-add-rle-decompression.patch b/target/linux/ar71xx/patches-3.3/310-lib-add-rle-decompression.patch
new file mode 100644 (file)
index 0000000..0cb9462
--- /dev/null
+++ b/target/linux/ar71xx/patches-3.3/310-lib-add-rle-decompression.patch
@@ -0,0 +1,114 @@
+--- a/lib/Kconfig
++++ b/lib/Kconfig
+@@ -124,6 +124,9 @@ config LZMA_COMPRESS
+ config LZMA_DECOMPRESS
+     tristate
+ 
++config RLE_DECOMPRESS
++      tristate
++
+ #
+ # These all provide a common interface (hence the apparent duplication with
+ # ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
+--- a/lib/Makefile
++++ b/lib/Makefile
+@@ -85,6 +85,7 @@ obj-$(CONFIG_XZ_DEC) += xz/
+ obj-$(CONFIG_RAID6_PQ) += raid6/
+ obj-$(CONFIG_LZMA_COMPRESS) += lzma/
+ obj-$(CONFIG_LZMA_DECOMPRESS) += lzma/
++obj-$(CONFIG_RLE_DECOMPRESS) += rle.o
+ 
+ lib-$(CONFIG_DECOMPRESS_GZIP) += decompress_inflate.o
+ lib-$(CONFIG_DECOMPRESS_BZIP2) += decompress_bunzip2.o
+--- /dev/null
++++ b/include/linux/rle.h
+@@ -0,0 +1,8 @@
++#ifndef _RLE_H_
++#define _RLE_H_
++
++int rle_decode(const unsigned char *src, size_t srclen,
++             unsigned char *dst, size_t dstlen,
++             size_t *src_done, size_t *dst_done);
++
++#endif /* _RLE_H_ */
+--- /dev/null
++++ b/lib/rle.c
+@@ -0,0 +1,78 @@
++/*
++ *  RLE decoding routine
++ *
++ *  Copyright (C) 2012 Gabor Juhos <juhosg@openwrt.org>
++ *
++ *  This program is free software; you can redistribute it and/or modify it
++ *  under the terms of the GNU General Public License version 2 as published
++ *  by the Free Software Foundation.
++ */
++
++#include <linux/kernel.h>
++#include <linux/module.h>
++#include <linux/rle.h>
++
++int rle_decode(const unsigned char *src, size_t srclen,
++             unsigned char *dst, size_t dstlen,
++             size_t *src_done, size_t *dst_done)
++{
++      size_t srcpos, dstpos;
++      int ret;
++
++      srcpos = 0;
++      dstpos = 0;
++      ret = -EINVAL;
++
++      /* sanity checks */
++      if (!src || !srclen || !dst || !dstlen)
++              goto out;
++
++      while (1) {
++              char count;
++
++              if (srcpos >= srclen)
++                      break;
++
++              count = (char) src[srcpos++];
++              if (count == 0) {
++                      ret = 0;
++                      break;
++              }
++
++              if (count > 0) {
++                      unsigned char c;
++
++                      if (srcpos >= srclen)
++                              break;
++
++                      c = src[srcpos++];
++
++                      while (count--) {
++                              if (dstpos >= dstlen)
++                                      break;
++
++                              dst[dstpos++] = c;
++                      }
++              } else {
++                      count *= -1;
++
++                      while (count--) {
++                              if (srcpos >= srclen)
++                                      break;
++                              if (dstpos >= dstlen)
++                                      break;
++                              dst[dstpos++] = src[srcpos++];
++                      }
++              }
++      }
++
++out:
++      if (src_done)
++              *src_done = srcpos;
++      if (dst_done)
++              *dst_done = dstpos;
++
++      return ret;
++}
++
++EXPORT_SYMBOL_GPL(rle_decode);