rbextract: add package

[openwrt/staging/wigyori.git] / package / utils / rbextract / src / rle.c

diff --git a/package/utils/rbextract/src/rle.c b/package/utils/rbextract/src/rle.c
new file mode 100644 (file)
index 0000000..ca198ee
--- /dev/null
+++ b/package/utils/rbextract/src/rle.c
@@ -0,0 +1,80 @@
+/*
+ *  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 <stdio.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <sys/types.h>
+ 
+#include "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 = 1;
+
+       /* sanity checks */
+       if (!src || !srclen || !dst || !dstlen)
+               goto out;
+
+       while (1) {
+               signed char count;
+
+               if (srcpos >= srclen)
+                       break;
+
+               count = (signed 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;
+}