Implement version table support for int21/ah=4b, subfunctions 0 and 1

Author: Mondgestein

build.bat

@@ -117,6 +117,13 @@ cd ..\kernel
 %MAKE% production
 if errorlevel 1 goto abort-cd
 
+echo.
+echo Process SETVER +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+echo.
+cd ..\setver
+%MAKE% production
+if errorlevel 1 goto abort-cd
+
 cd ..
 
 set XERROR=

clean.bat

@@ -27,6 +27,9 @@ cd ..\sys
 cd ..\kernel
 %MAKE% clean
 
+cd ..\setver
+%MAKE% clean
+
 cd ..\hdr
 if exist *.bak del *.bak
 

clobber.bat

@@ -27,6 +27,9 @@ cd ..\sys
 cd ..\kernel
 %MAKE% clobber
 
+cd ..\setver
+%MAKE% clobber
+
 cd ..\hdr
 if exist *.bak del *.bak
 

kernel/globals.h

@@ -268,6 +268,8 @@ extern BYTE ASM ErrorMode,          /* Critical error flag                  */
   ASM CritErrClass, ASM VgaSet, 
   ASM njoined;                      /* number of joined devices             */
 
+extern VOID FAR * ASM setverPtr;    /* Pointer to SETVER list               */
+
 extern UWORD ASM Int21AX;
 extern COUNT ASM CritErrCode;
 extern BYTE FAR * ASM CritErrDev;

kernel/kernel.asm

@@ -407,7 +407,8 @@ _nul_dev:           ; 0022 device chain root
                 global  _njoined
 _njoined        db      0               ; 0034 number of joined devices
                 dw      0               ; 0035 DOS 4 pointer to special names (always zero in DOS 5)
-setverPtr       dw      0,0             ; 0037 setver list
+                global  _setverPtr
+_setverPtr      dw      0,0             ; 0037 setver list
                 dw      0               ; 003B cs offset for fix a20
                 dw      0               ; 003D psp of last umb exec
                 global _LoL_nbuffers

kernel/task.c

@@ -92,6 +92,44 @@ ULONG SftGetFsize(int sft_idx)
   return s->sft_size;
 }
 
+STATIC WORD SetverCompareFilename(BYTE FAR *m1, BYTE FAR *m2, COUNT c)
+{
+  while (c--)
+  {
+    if (toupper(*m1) != toupper(*m2))
+    {
+      return *m1 - *m2;
+    }
+
+    m1 = m1 + 1; m2 = m2 + 1;
+  }
+
+  return 0;
+}
+
+STATIC UWORD SetverGetVersion(BYTE FAR *table, BYTE FAR *name)
+{
+  BYTE FAR *len;
+  COUNT nlen;
+
+  if ((table != NULL) && (name != NULL))
+  {
+    nlen = fstrlen(name);
+
+    while (*(len = table) != 0)
+    {
+      if ((*len == nlen) && (SetverCompareFilename(name, table + 1, *len) == 0))
+      {
+        return *((UWORD FAR *)(table + *len + 1));
+      }
+
+      table = table + *len + 3;
+    }
+  }
+
+  return 0;
+}
+
 STATIC COUNT ChildEnv(exec_blk * exp, UWORD * pChildEnvSeg, char far * pathname)
 {
   BYTE FAR *pSrc;
@@ -242,6 +280,7 @@ STATIC UWORD patchPSP(UWORD pspseg, UWORD envseg, exec_blk FAR * exb,
   mcb FAR *pspmcb;
   int i;
   BYTE FAR *np;
+  UWORD fakever;
 
   pspmcb = MK_FP(pspseg, 0);
   ++pspseg;
@@ -287,6 +326,11 @@ STATIC UWORD patchPSP(UWORD pspseg, UWORD envseg, exec_blk FAR * exb,
   if (i < 8)
     pspmcb->m_name[i] = '\0';
 
+  if ((fakever = SetverGetVersion(setverPtr, np)) != 0)
+  {
+    psp->ps_retdosver = fakever;
+  }
+
   /* return value: AX value to be passed based on FCB values */
   return (get_cds1(psp->ps_fcb1.fcb_drive) ? 0 : 0xff) |
     (get_cds1(psp->ps_fcb2.fcb_drive) ? 0 : 0xff00);

makefile

@@ -91,8 +91,8 @@ XUPX=upx --8086 --best
 XNASM=nasm
 ifeq ($(COMPILER),gcc)
 MAKE=make
-MAKEADJUST=for i in utils lib drivers boot sys kernel; do sed 's@!include "\(.*\)"@include ../mkfiles/gcc.mak@' < $$i/makefile > $$i/GNUmakefile; done
-MAKEREMOVE=for i in utils lib drivers boot sys kernel; do rm -f $$i/GNUmakefile; done
+MAKEADJUST=for i in utils lib drivers boot sys kernel setver; do sed 's@!include "\(.*\)"@include ../mkfiles/gcc.mak@' < $$i/makefile > $$i/GNUmakefile; done
+MAKEREMOVE=for i in utils lib drivers boot sys kernel setver; do rm -f $$i/GNUmakefile; done
 XLINK=ia16-elf-gcc
 else
 MAKE=wmake -ms -h
@@ -115,6 +115,7 @@ all:
 	cd boot && $(MAKE) production
 	cd sys && $(MAKE) production
 	cd kernel && $(MAKE) production
+	cd setver && $(MAKE) production
 	$(MAKEREMOVE)
 
 clean:
@@ -125,6 +126,7 @@ clean:
 	cd boot && $(MAKE) clean
 	cd sys && $(MAKE) clean
 	cd kernel && $(MAKE) clean
+	cd setver && $(MAKE) clean
 	$(MAKEREMOVE)
 
 clobber:
@@ -135,4 +137,5 @@ clobber:
 	cd boot && $(MAKE) clobber
 	cd sys && $(MAKE) clobber
 	cd kernel && $(MAKE) clobber
+	cd setver && $(MAKE) clobber
 	$(MAKEREMOVE)

setver/makefile

@@ -0,0 +1,17 @@
+#
+# makefile for setver.sys
+#
+
+!include "../mkfiles/generic.mak"
+
+
+production:     setver.sys
+
+setver.sys:     setver.asm
+		$(NASM) -o ..$(DIRSEP)bin$(DIRSEP)setver.sys setver.asm
+
+clobber:	clean
+
+clean:
+		-$(RM) *.obj *.map *.lst *.err
+

setver/setver.asm

@@ -0,0 +1,81 @@
+;
+; Initially written by Ricardo Hanke
+; Released under the terms of the GNU General Public License.
+; See the file 'COPYING' in the main directory for details.
+;
+; This driver loads the list of special programs into memory.
+;
+
+section    .text
+
+
+COMMAND    equ   2
+STATUS     equ   3
+DRIVEREND  equ   14
+
+FAKETABLE  equ   37h
+
+
+header     dw    -1, -1
+           dw    1000000000000000b
+           dw    strategy
+           dw    interrupt
+           db    "SETVERXX"
+
+           dw    signature
+
+paramblock dd    0
+
+
+strategy:  mov   [cs:paramblock + 0], bx
+           mov   [cs:paramblock + 2], es
+           retf
+
+
+interrupt: push  ax
+           push  bx
+           push  di
+           push  es
+           pushf
+
+           les   di, [paramblock]
+           mov   bl, [es:di + COMMAND]
+           cmp   bl, 0
+           jne   error
+
+           mov   ax, table
+           add   ax, [length]
+
+           mov   word [es:di + DRIVEREND + 0], ax
+           mov   word [es:di + DRIVEREND + 2], cs
+
+           mov   ah, 52h
+           int   21h
+
+           mov   word [es:bx + FAKETABLE + 0], table
+           mov   word [es:bx + FAKETABLE + 2], cs
+
+           xor   ax, ax
+           jmp   exit
+
+error:     mov   ax, 8003h
+
+exit:      or    ax, 0100h
+           mov   [es:di + STATUS], ax
+
+           popf
+           pop   es
+           pop   di
+           pop   bx
+           pop   ax
+
+           retf
+
+
+signature  db    'SDIR'
+length     dw    1
+
+table      ;db    11, "SHOWVER.EXE",  5, 00
+           ;db    12, "BUGGYPRG.EXE", 3, 31
+
+           db    0