Initial checking of Gob engine

svn-id: r17388

1 files changed, 94 insertions, 0 deletions

diff --git a/gob/pack.cpp b/gob/pack.cpp
new file mode 100644
index 0000000000..064321c5e9
--- /dev/null
+++ b/gob/pack.cpp
@@ -0,0 +1,94 @@
+/*
+** Gobliiins 1
+** Original game by CoktelVision
+**
+** Reverse engineered by Ivan Dubrov <WFrag@yandex.ru>
+**
+*/
+#include "gob/gob.h"
+#include "gob/pack.h"
+#include "gob/debug.h"
+
+namespace Gob {
+
+int32 unpackData(char *sourceBuf, char *destBuf) {
+	uint32 realSize;
+	uint32 counter;
+	uint16 cmd;
+	byte *src;
+	byte *dest;
+	byte *tmpBuf;
+	int16 off;
+	byte len;
+	byte i;
+	int16 j;
+	uint16 tmpIndex;
+
+	realSize = READ_LE_UINT32(sourceBuf);
+	counter = READ_LE_UINT32(sourceBuf);
+
+	tmpBuf = (byte *)malloc(4114);
+
+	/*
+	 * Can use assembler unpacker for small blocks - for speed.
+	 * Don't need this anymore :)
+	 */
+	/*
+	 * if(realSize < 65000)
+	 * {
+	 * asm_unpackData(sourceBuf, destBuf, tmpBuf);
+	 * free(tmpBuf);
+	 * return realSize;
+	 * }
+	 */
+
+	if (tmpBuf == 0)
+		return 0;
+
+	for (j = 0; j < 4078; j++)
+		tmpBuf[j] = 0x20;
+	tmpIndex = 4078;
+
+	src = (byte *)(sourceBuf + 4);
+	dest = (byte *)destBuf;
+
+	cmd = 0;
+	while (1) {
+		cmd >>= 1;
+		if ((cmd & 0x0100) == 0) {
+			cmd = *src | 0xff00;
+			src++;
+		}
+		if ((cmd & 1) != 0) {	/* copy */
+			*dest++ = *src;
+			tmpBuf[tmpIndex] = *src;
+			src++;
+			tmpIndex++;
+			tmpIndex %= 4096;
+			counter--;
+			if (counter == 0)
+				break;
+		} else {	/* copy string */
+
+			off = *src++;
+			off |= (*src & 0xf0) << 4;
+			len = (*src & 0x0f) + 3;
+			src++;
+			for (i = 0; i < len; i++) {
+				*dest++ = tmpBuf[(off + i) % 4096];
+				counter--;
+				if (counter == 0) {
+					free(tmpBuf);
+					return realSize;
+				}
+				tmpBuf[tmpIndex] = tmpBuf[(off + i) % 4096];
+				tmpIndex++;
+				tmpIndex %= 4096;
+			}
+		}
+	}
+	free(tmpBuf);
+	return realSize;
+}
+
+}				// End of namespace Gob