Added structures for parsing data stream from windbg to packet.

Signed-off-by: Mihail Abakumov <mikhail.abakumov@ispras.ru>
Signed-off-by: Pavel Dovgalyuk <dovgaluk@ispras.ru>
Signed-off-by: Dmitriy Koltunov <koltunov@ispras.ru>
---
 include/exec/windbgstub-utils.h |   11 +++++++++++
 windbgstub.c                    |   30 ++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/include/exec/windbgstub-utils.h b/include/exec/windbgstub-utils.h
index ced03b0663..b7e65faefe 100755
--- a/include/exec/windbgstub-utils.h
+++ b/include/exec/windbgstub-utils.h
@@ -52,6 +52,17 @@ typedef struct InitedAddr {
     bool is_init;
 } InitedAddr;
 
+typedef struct PacketData {
+    union {
+        struct {
+            DBGKD_MANIPULATE_STATE64 m64;
+            uint8_t extra[0];
+        };
+        uint8_t buf[PACKET_MAX_SIZE];
+    };
+    uint16_t extra_size;
+} PacketData;
+
 InitedAddr *windbg_get_KPCR(void);
 InitedAddr *windbg_get_version(void);
 
diff --git a/windbgstub.c b/windbgstub.c
index e9aabd807b..395f244d4f 100755
--- a/windbgstub.c
+++ b/windbgstub.c
@@ -19,6 +19,36 @@
 #include "sysemu/kvm.h"
 #include "sysemu/reset.h"
 
+typedef enum ParsingState {
+    STATE_LEADER,
+    STATE_PACKET_TYPE,
+    STATE_PACKET_BYTE_COUNT,
+    STATE_PACKET_ID,
+    STATE_PACKET_CHECKSUM,
+    STATE_PACKET_DATA,
+    STATE_TRAILING_BYTE,
+} ParsingState;
+
+typedef enum ParsingResult {
+    RESULT_NONE,
+    RESULT_BREAKIN_BYTE,
+    RESULT_UNKNOWN_PACKET,
+    RESULT_CONTROL_PACKET,
+    RESULT_DATA_PACKET,
+    RESULT_ERROR,
+} ParsingResult;
+
+typedef struct ParsingContext {
+    /* index in the current buffer,
+       which depends on the current state */
+    int index;
+    ParsingState state;
+    ParsingResult result;
+    KD_PACKET packet;
+    PacketData data;
+    const char *name;
+} ParsingContext;
+
 typedef struct WindbgState {
     bool is_loaded;