From fc56849d679ac766faa2441dd0ac0976f9ba3174 Mon Sep 17 00:00:00 2001
From: John Hodge <tpg@mutabah.net>
Date: Sun, 15 Jul 2012 12:49:09 +0800
Subject: [PATCH] Kernel - Debugging AxWin3 error

---
 KernelLand/Kernel/drv/vterm.c | 13 +++++++------
 KernelLand/Kernel/vfs/io.c    | 18 +++++++++++++++---
 2 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/KernelLand/Kernel/drv/vterm.c b/KernelLand/Kernel/drv/vterm.c
index 7d30511f..a6a1c66d 100644
--- a/KernelLand/Kernel/drv/vterm.c
+++ b/KernelLand/Kernel/drv/vterm.c
@@ -353,8 +353,7 @@ int VT_Root_IOCtl(tVFS_Node *Node, int Id, void *Data)
  */
 size_t VT_Read(tVFS_Node *Node, off_t Offset, size_t Length, void *Buffer)
 {
-	 int	pos = 0;
-	 int	avail;
+	 int	pos, avail;
 	tVTerm	*term = &gVT_Terminals[ Node->Inode ];
 	Uint32	*codepoint_buf = Buffer;
 	Uint32	*codepoint_in;
@@ -373,9 +372,10 @@ size_t VT_Read(tVFS_Node *Node, off_t Offset, size_t Length, void *Buffer)
 		avail = term->InputWrite - term->InputRead;
 		if(avail < 0)
 			avail += MAX_INPUT_CHARS8;
-		if(avail > Length - pos)
-			avail = Length - pos;
+		if(avail > Length)
+			avail = Length;
 		
+		pos = 0;
 		while( avail -- )
 		{
 			((char*)Buffer)[pos] = term->InputBuffer[term->InputRead];
@@ -395,12 +395,13 @@ size_t VT_Read(tVFS_Node *Node, off_t Offset, size_t Length, void *Buffer)
 		if(avail < 0)
 			avail += MAX_INPUT_CHARS32;
 		Length /= 4;
-		if(avail > Length - pos)
-			avail = Length - pos;
+		if(avail > Length)
+			avail = Length;
 		
 		codepoint_in = (void*)term->InputBuffer;
 		codepoint_buf = Buffer;
 		
+		pos = 0;
 		while( avail -- )
 		{
 			codepoint_buf[pos] = codepoint_in[term->InputRead];
diff --git a/KernelLand/Kernel/vfs/io.c b/KernelLand/Kernel/vfs/io.c
index e7a2a068..dacf720e 100644
--- a/KernelLand/Kernel/vfs/io.c
+++ b/KernelLand/Kernel/vfs/io.c
@@ -20,12 +20,24 @@ Uint64 VFS_Read(int FD, Uint64 Length, void *Buffer)
 	ENTER("iFD XLength pBuffer", FD, Length, Buffer);
 	
 	h = VFS_GetHandle(FD);
-	if(!h)	LEAVE_RET('i', -1);
+	if(!h) {
+		LOG("Bad Handle");
+		LEAVE_RET('i', -1);
+	}
 	
-	if( !(h->Mode & VFS_OPENFLAG_READ) || h->Node->Flags & VFS_FFLAG_DIRECTORY )
+	if( !(h->Mode & VFS_OPENFLAG_READ) ) {
+		LOG("Bad mode");
+		LEAVE_RET('i', -1);
+	}
+	if( (h->Node->Flags & VFS_FFLAG_DIRECTORY) ) {
+		LOG("Reading directory");
 		LEAVE_RET('i', -1);
+	}
 
-	if(!h->Node->Type || !h->Node->Type->Read)	LEAVE_RET('i', 0);
+	if(!h->Node->Type || !h->Node->Type->Read) {
+		LOG("No read method");
+		LEAVE_RET('i', -1);
+	}
 	
 	ret = h->Node->Type->Read(h->Node, h->Position, Length, Buffer);
 	if(ret == -1)	LEAVE_RET('i', -1);
-- 
2.20.1