arch/m68k-all/dos/bcpl_patches.c

   1 /*
   2     Copyright © 1995-2014, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include <aros/asmcall.h>
   7 #include <string.h>
   8 #include <exec/libraries.h>
   9 #include <dos/dosextens.h>
  10 #include <dos/dos.h>
  11 #include <proto/arossupport.h>
  12 #include <proto/exec.h>
  13 #include <proto/dos.h>
  14
  15 #include "bcpl.h"
  16
  17 /* CallGlobVec lives in the private function (4) */
  18 AROS_UFP5(LONG, CallGlobVec,
  19     AROS_UFPA(LONG, function, D0),
  20     AROS_UFPA(LONG, d1, D1),
  21     AROS_UFPA(LONG, d2, D2),
  22     AROS_UFPA(LONG, d3, D3),
  23     AROS_UFPA(LONG, d4, D4));
  24
  25
  26 /* LoadSeg() needs D1-D3 parameters for overlay hunk support */
  27 AROS_UFP4(BPTR, LoadSeg_Overlay,
  28     AROS_UFPA(UBYTE*, name, D1),
  29     AROS_UFPA(BPTR, hunktable, D2),
  30     AROS_UFPA(BPTR, fh, D3),
  31     AROS_UFPA(struct DosLibrary *, DosBase, A6));
  32
  33 static AROS_UFH2(BPTR, NoReqLoadSeg,
  34     AROS_UFPA(BSTR, name, D1),
  35     AROS_UFPA(struct DosLibrary *, DOSBase, A6))
  36 {
  37     AROS_USERFUNC_INIT
  38
  39     BPTR ret = BNULL;
  40
  41     if (name != BNULL) {
  42         struct Process *me = (struct Process *)FindTask(NULL);
  43         int len = AROS_BSTR_strlen(name);
  44         TEXT buff[len+1];
  45         APTR oldWindowPtr;
  46
  47         CopyMem(buff, AROS_BSTR_ADDR(name), len);
  48         buff[len] = 0;
  49
  50         oldWindowPtr = me->pr_WindowPtr;
  51         me->pr_WindowPtr = (APTR)-1;
  52         ret = LoadSeg(buff);
  53         me->pr_WindowPtr = oldWindowPtr;
  54     } else {
  55         SetIoErr(ERROR_OBJECT_NOT_FOUND);
  56     }
  57
  58     return ret;
  59
  60     AROS_USERFUNC_EXIT
  61 }
  62
  63 AROS_UFH5(BPTR, LoadSeg_Check,
  64     AROS_UFPA(UBYTE*, name, D1),
  65     AROS_UFPA(BPTR, hunktable, D2),
  66     AROS_UFPA(BPTR, fh, D3),
  67     AROS_UFPA(APTR, LoadSeg_Original, A0),
  68     AROS_UFPA(struct DosLibrary *, DOSBase, A6))
  69 {
  70     AROS_USERFUNC_INIT
  71
  72     UBYTE *filename;
  73
  74     /* name == NULL: Overlay LoadSeg */
  75     if (name == NULL)
  76         return AROS_UFC4(BPTR, LoadSeg_Overlay,
  77             AROS_UFCA(UBYTE*, name, D1),
  78             AROS_UFCA(BPTR, hunktable, D2),
  79             AROS_UFCA(BPTR, fh, D3),
  80             AROS_UFCA(struct DosLibrary *, DOSBase, A6));
  81
  82     filename = FilePart(name);
  83
  84     /* Do not allow Picasso96 to load, it is not
  85      * compatible with built-in AROS RTG system */
  86     if (stricmp(filename,"rtg.library") == 0)
  87         return BNULL;
  88
  89     /* Call original LoadSeg function */
  90     return AROS_UFC2(BPTR, LoadSeg_Original,
  91         AROS_UFCA(UBYTE*, name, D1),
  92         AROS_UFCA(struct DosLibrary *, DOSBase, A6));
  93
  94     AROS_USERFUNC_EXIT
  95 }
  96
  97 extern void *BCPL_jsr, *BCPL_rts;
  98 extern const ULONG BCPL_GlobVec[(BCPL_GlobVec_NegSize + BCPL_GlobVec_PosSize) >> 2];
  99
 100 const UWORD highfunc = 37, lowfunc = 5, skipfuncs = 2;
 101
 102 #define PATCHMEM_SIZE (10 * (highfunc - lowfunc + 1 - skipfuncs) * sizeof(UWORD) + 13 * sizeof(UWORD))
 103
 104 /* This patches two compatibility problems with badly written programs:
 105  * 1) Return value in both D0 and D1.
 106  * 2) 1.x original DOS functions can be called without DOSBase in A6.
 107  * Both "features" are original BCPL DOS side-effects.
 108  */
 109
 110 static int PatchDOS(struct DosLibrary *dosbase)
 111 {
 112     UWORD i;
 113     UWORD *asmcall, *asmmem;
 114     IPTR func;
 115     APTR GlobVec;
 116
 117     GlobVec = AllocMem(BCPL_GlobVec_NegSize + BCPL_GlobVec_PosSize, MEMF_PUBLIC);
 118     if (GlobVec == NULL)
 119         return FALSE;
 120
 121     CopyMem(BCPL_GlobVec, GlobVec, BCPL_GlobVec_NegSize + BCPL_GlobVec_PosSize);
 122     GlobVec += BCPL_GlobVec_NegSize;
 123     *(APTR *)(GlobVec + GV_DOSBase) = dosbase;
 124
 125     Forbid();
 126
 127     /* Use this private slot for the C-to-BCPL thunk */
 128     __AROS_INITVEC(dosbase, 4);
 129     __AROS_SETVECADDR(dosbase, 4, CallGlobVec);
 130
 131     asmmem = asmcall = AllocMem(PATCHMEM_SIZE, MEMF_PUBLIC);
 132
 133     for (i = lowfunc; i <= highfunc; i++)
 134     {
 135         if (i == 24 || i == 25)
 136             continue;
 137         func = (IPTR)__AROS_GETJUMPVEC(dosbase, i)->vec;
 138         __AROS_SETVECADDR(dosbase, i, asmcall);
 139         *asmcall++ = 0x2f0e; // MOVE.L A6,-(SP)
 140         *asmcall++ = 0x4df9; // LEA dosbase,A6
 141         *asmcall++ = (UWORD)((ULONG)dosbase >> 16);
 142         *asmcall++ = (UWORD)((ULONG)dosbase >>  0);
 143         *asmcall++ = 0x4eb9; // JSR func
 144         *asmcall++ = (UWORD)(func >> 16);
 145         *asmcall++ = (UWORD)(func >>  0);
 146         *asmcall++ = 0x2C5F; // MOVE.L (SP)+,A6
 147         *asmcall++ = 0x2200; // MOVE.L D0,D1
 148         *asmcall++ = 0x4e75; // RTS
 149     }
 150
 151     /* NoReqLoadSeg() patch */
 152     SetFunction((struct Library *)dosbase, 28, NoReqLoadSeg);
 153
 154     /* LoadSeg() patch */
 155     func = (IPTR)__AROS_GETJUMPVEC(dosbase, 25)->vec;
 156     __AROS_SETVECADDR(dosbase, 25, asmcall);
 157     *asmcall++ = 0x2f0e; // MOVE.L A6,-(SP)
 158     *asmcall++ = 0x4df9; // LEA dosbase,A6
 159     *asmcall++ = (UWORD)((ULONG)dosbase >> 16);
 160     *asmcall++ = (UWORD)((ULONG)dosbase >>  0);
 161     *asmcall++ = 0x41f9; // LEA func,A0
 162     *asmcall++ = (UWORD)(func >> 16);
 163     *asmcall++ = (UWORD)(func >>  0);
 164     *asmcall++ = 0x4eb9; // jsr LoadSeg_Check
 165     *asmcall++ = (UWORD)((ULONG)LoadSeg_Check >> 16);
 166     *asmcall++ = (UWORD)((ULONG)LoadSeg_Check >>  0);
 167     *asmcall++ = 0x2C5F; // MOVE.L (SP)+,A6
 168     *asmcall++ = 0x2200; // MOVE.L D0,D1
 169     *asmcall++ = 0x4e75; // RTS
 170
 171     CacheClearE(asmmem, PATCHMEM_SIZE, CACRF_ClearI|CACRF_ClearD);
 172
 173     dosbase->dl_A5 = (LONG)&BCPL_jsr;
 174     dosbase->dl_A6 = (LONG)&BCPL_rts;
 175     dosbase->dl_GV = (APTR)GlobVec;
 176
 177     Permit();
 178
 179     return TRUE;
 180 }
 181
 182 ADD2INITLIB(PatchDOS, 0)
 183
 184 static int UnPatchDOS(struct DosLibrary *dosbase)
 185 {
 186     APTR asmcall;
 187
 188     asmcall = __AROS_GETJUMPVEC(dosbase, lowfunc)->vec;
 189     FreeMem(asmcall, PATCHMEM_SIZE);
 190     FreeMem(dosbase->dl_GV - BCPL_GlobVec_NegSize, BCPL_GlobVec_NegSize + BCPL_GlobVec_PosSize);
 191
 192     return TRUE;
 193 }
 194
 195 ADD2EXPUNGELIB(UnPatchDOS, 0)