From d60f2f6da066a21bddc6a352e029db39ca5e499d Mon Sep 17 00:00:00 2001
From: Ulf Wohlers <finsterr@users.sourceforge.net>
Date: Tue, 27 Aug 2002 10:30:33 +0000
Subject: [PATCH] Added DOS_InfoBlock - firstMCB support

Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@229
---
 src/dos/dos.cpp         | 14 ++++++++------
 src/dos/dos_classes.cpp | 20 ++++++++++++++++++++
 src/dos/dos_memory.cpp  |  4 ++++
 3 files changed, 32 insertions(+), 6 deletions(-)

diff --git a/src/dos/dos.cpp b/src/dos/dos.cpp
index 33439ad1..a2f40513 100644
--- a/src/dos/dos.cpp
+++ b/src/dos/dos.cpp
@@ -29,6 +29,8 @@
 #include "dos_inc.h"
 
 DOS_Block dos;
+DOS_InfoBlock dosInfoBlock;
+
 static Bit8u dos_copybuf[0x10000];
 static Bitu call_20,call_21,call_theend;
 
@@ -532,7 +534,6 @@ static Bitu DOS_21Handler(void) {
 			CALLBACK_SCF(true);
 		}
 		break;
-		break;
 	case 0x47:					/* CWD Get current directory */
 		//TODO Memory
 		if (DOS_GetCurrentDir(reg_dl,name1)) {
@@ -628,11 +629,12 @@ static Bitu DOS_21Handler(void) {
 	case 0x51:					/* Get current PSP */
 		reg_bx=dos.psp;
 		break;
-	case 0x52:					/* Get list of lists */
-		SegSet16(es,0);
-		reg_bx=0;
-		LOG_ERROR("Call is made for list of lists not supported let's hope for the best");
-		break;
+	case 0x52: {				/* Get list of lists */
+		Bit16u seg;
+		dosInfoBlock.GetDIBPointer(seg,reg_bx);
+		SegSet16(es,seg);
+		LOG_DEBUG("Call is made for list of lists - let's hope for the best");
+		break; }
 //TODO Think hard how shit this is gonna be
 //And will any game ever use this :)
 	case 0x53:					/* Translate BIOS parameter block to drive parameter block */
diff --git a/src/dos/dos_classes.cpp b/src/dos/dos_classes.cpp
index 42c14913..04cd8a33 100644
--- a/src/dos/dos_classes.cpp
+++ b/src/dos/dos_classes.cpp
@@ -266,3 +266,23 @@ RealPt DOS_ParamBlock::cmdtail(void){
 	return mem_readd(off+offsetof(sParamBlock,exec.cmdtail));
 }
 
+// * Dos Info Block (list of lists) *
+
+void DOS_InfoBlock::SetLocation(Bit16u segment)
+{
+	seg = segment;
+	dib = (SDosInfoBlock*)HostMake(segment,0);
+	Bit16u size = sizeof(SDosInfoBlock);
+	memset(dib,0,sizeof(SDosInfoBlock));
+};
+
+void DOS_InfoBlock::SetFirstMCB(RealPt pt)
+{
+	dib->firstMCB = pt;
+};
+
+void DOS_InfoBlock::GetDIBPointer(Bit16u& segment, Bit16u& offset)
+{
+	segment = seg;
+	offset	= offsetof(SDosInfoBlock,firstDPB);
+};
diff --git a/src/dos/dos_memory.cpp b/src/dos/dos_memory.cpp
index 2a4bcc14..14e8a5d9 100644
--- a/src/dos/dos_memory.cpp
+++ b/src/dos/dos_memory.cpp
@@ -158,5 +158,9 @@ void DOS_SetupMemory(void) {
 	mcb->size=0x9FFE - MEM_START;
 	mcb->type=0x5a;									//Last Block
 	dos.firstMCB=MEM_START;
+
+	// Create Dos Info Block : maximum size 95 Bytes....
+	dosInfoBlock.SetLocation(DOS_GetMemory(6));
+	dosInfoBlock.SetFirstMCB(RealMake(dos.firstMCB,0));
 }