[KDGDB] Various fixes and improvements

drivers/base/kdgdb/gdb_input.c

@@ -368,15 +368,16 @@ handle_gdb_query(void)
             PLDR_DATA_TABLE_ENTRY TableEntry = CONTAINING_RECORD(CurrentEntry, LDR_DATA_TABLE_ENTRY, InLoadOrderLinks);
             PVOID DllBase = (PVOID)((ULONG_PTR)TableEntry->DllBase + 0x1000);
             LONG mem_length;
-            char* ptr;
+            USHORT i;
 
             /* Convert names to lower case. Yes this _is_ ugly */
-            _snprintf(name_helper, 64, "%wZ", &TableEntry->BaseDllName);
-            for (ptr = name_helper; *ptr; ptr++)
+            for (i = 0; i < (TableEntry->BaseDllName.Length / sizeof(WCHAR)); i++)
             {
-                if (*ptr >= 'A' && *ptr <= 'Z')
-                    *ptr += 'a' - 'A';
+                name_helper[i] = (char)TableEntry->BaseDllName.Buffer[i];
+                if (name_helper[i] >= 'A' && name_helper[i] <= 'Z')
+                    name_helper[i] += 'a' - 'A';
             }
+            name_helper[i] = 0;
 
             /* GDB doesn't load the file if you don't prefix it with a drive letter... */
             mem_length = _snprintf(str_helper, 256, "<library name=\"C:\\%s\"><segment address=\"0x%p\"/></library>", &name_helper, DllBase);
@@ -404,7 +405,6 @@ handle_gdb_query(void)
         }
 
         return finish_gdb_packet();
-   
     }
 
     KDDBGPRINT("KDGDB: Unknown query: %s\n", gdb_input);

drivers/base/kdgdb/gdb_receive.c

@@ -30,24 +30,22 @@ KDSTATUS
 NTAPI
 gdb_receive_packet(_Inout_ PKD_CONTEXT KdContext)
 {
-    UCHAR* ByteBuffer = (UCHAR*)gdb_input;
+    UCHAR* ByteBuffer;
     UCHAR Byte;
     KDSTATUS Status;
-    CHAR CheckSum = 0, ReceivedCheckSum;
+    CHAR CheckSum, ReceivedCheckSum;
 
     do
     {
         Status = KdpReceiveByte(&Byte);
         if (Status != KdPacketReceived)
             return Status;
-        if (Byte == 0x03)
-        {
-            KDDBGPRINT("BREAK!");
-            KdContext->KdpControlCPending = TRUE;
-            return KdPacketNeedsResend;
-        }
     } while (Byte != '$');
 
+get_packet:
+    CheckSum = 0;
+    ByteBuffer = (UCHAR*)gdb_input;
+
     while (TRUE)
     {
         /* Try to get a byte from the port */
@@ -94,6 +92,20 @@ end:
         return KdPacketNeedsResend;
     }
 
+    /* Ensure there is nothing left in the pipe */
+    while (KdpPollByte(&Byte) == KdPacketReceived)
+    {
+        switch (Byte)
+        {
+            case '$':
+                KDDBGPRINT("Received new packet just after %s.\n", gdb_input);
+                goto get_packet;
+            case 0x03: 
+                KdContext->KdpControlCPending = TRUE;
+                break;
+        }
+    }
+
     /* Acknowledge */
     KdpSendByte('+');
 

drivers/base/kdgdb/kdcom.c

@@ -129,11 +129,9 @@ KdpPortInitialize(IN ULONG ComPortNumber,
     {
         return STATUS_INVALID_PARAMETER;
     }
-    else
-    {
-        KdComPortInUse = KdComPort.Address;
-        return STATUS_SUCCESS;
-    }
+
+    KdComPortInUse = KdComPort.Address;
+    return STATUS_SUCCESS;
 }
 
 /******************************************************************************
@@ -300,7 +298,13 @@ KDSTATUS
 NTAPI
 KdpReceiveByte(_Out_ PUCHAR OutByte)
 {
-    USHORT CpStatus = CpGetByte(&KdComPort, OutByte, TRUE, FALSE);
+    USHORT CpStatus;
+    
+    do
+    {
+        CpStatus = CpGetByte(&KdComPort, OutByte, TRUE, FALSE);
+    } while (CpStatus == CP_GET_NODATA);
+    
     /* Get the byte */
     if (CpStatus == CP_GET_SUCCESS)
     {

drivers/base/kdgdb/kdgdb.h

@@ -96,6 +96,7 @@ extern const char hex_chars[];
 KDSTATUS NTAPI KdpPollBreakIn(VOID);
 VOID NTAPI KdpSendByte(_In_ UCHAR Byte);
 KDSTATUS NTAPI KdpReceiveByte(_Out_ PUCHAR OutByte);
+KDSTATUS NTAPI KdpPollByte(OUT PUCHAR OutByte);
 
 /* kdpacket.c */
 extern DBGKD_ANY_WAIT_STATE_CHANGE CurrentStateChange;

drivers/base/kdgdb/kdpacket.c

@@ -360,15 +360,25 @@ KdReceivePacket(
     _Out_ PULONG DataLength,
     _Inout_ PKD_CONTEXT KdContext)
 {
-    KDDBGPRINT("KdReceivePacket.\n");
+    KDDBGPRINT("KdReceivePacket --> ");
 
     if (PacketType == PACKET_TYPE_KD_POLL_BREAKIN)
     {
+        static BOOLEAN firstTime = TRUE;
+        KDDBGPRINT("Polling break in.\n");
+        if (firstTime)
+        {
+            /* Force debug break on init */
+            firstTime = FALSE;
+            return KdPacketReceived;
+        }
+
         return KdpPollBreakIn();
     }
 
     if (PacketType == PACKET_TYPE_KD_DEBUG_IO)
     {
+        KDDBGPRINT("Debug prompt.\n");
         /* HACK ! RtlAssert asks for (boipt), always say "o" --> break once. */
         MessageData->Length = 1;
         MessageData->Buffer[0] = 'o';
@@ -379,14 +389,17 @@ KdReceivePacket(
     {
         DBGKD_MANIPULATE_STATE64* State = (DBGKD_MANIPULATE_STATE64*)MessageHeader->Buffer;
 
+        KDDBGPRINT("State manipulation: ");
+
         /* Maybe we are in a send<->receive loop that GDB doesn't need to know about */
         if (KdpManipulateStateHandler != NULL)
         {
-            KDDBGPRINT("KDGBD: We have a manipulate state handler.\n");
+            KDDBGPRINT("We have a manipulate state handler.\n");
             return KdpManipulateStateHandler(State, MessageData, DataLength, KdContext);
         }
 
         /* Receive data from GDB  and interpret it */
+        KDDBGPRINT("Receiving data from GDB.\n");
         return gdb_receive_and_interpret_packet(State, MessageData, DataLength, KdContext);
     }