src/lib/16_mm.c

   1 /* Catacomb Apocalypse Source Code
   2  * Copyright (C) 1993-2014 Flat Rock Software
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 // NEWMM.C
  20
  21 /*
  22 =============================================================================
  23
  24                         ID software memory manager
  25                         --------------------------
  26
  27 Primary coder: John Carmack
  28
  29 RELIES ON
  30 ---------
  31 Quit (char *error) function
  32
  33
  34 WORK TO DO
  35 ----------
  36 MM_SizePtr to change the size of a given pointer
  37
  38 Multiple purge levels utilized
  39
  40 EMS / XMS unmanaged routines
  41
  42 =============================================================================
  43 */
  44 /*
  45
  46 Open Watcom port by sparky4
  47
  48 */
  49 #include "src/lib/16_mm.h"
  50
  51 /*
  52 =============================================================================
  53
  54                                                  GLOBAL VARIABLES
  55
  56 =============================================================================
  57 */
  58
  59 void            (* beforesort) (void);
  60 void            (* aftersort) (void);
  61 void            (* XMSaddr) (void);             // far pointer to XMS driver
  62
  63 /*
  64 =============================================================================
  65
  66                                                  LOCAL VARIABLES
  67
  68 =============================================================================
  69 */
  70
  71 static  char *ParmStringsexmm[] = {"noems","noxms",""};
  72
  73 /*
  74 ======================
  75 =
  76 = MML_CheckForEMS
  77 =
  78 = Routine from p36 of Extending DOS
  79 =
  80 =======================
  81 */
  82
  83 boolean MML_CheckForEMS(void)
  84 {
  85         boolean emmcfems;
  86         static char     emmname[] = "EMMXXXX0"; //fix by andrius4669
  87 //              mov     dx,OFFSET emmname
  88         __asm {
  89                 //LEA   DX, emmname     //fix by andrius4669
  90                 mov     dx,OFFSET emmname       //fix by andrius4669
  91                 mov     ax,0x3d00
  92                 int     0x21            // try to open EMMXXXX0 device
  93                 jc      error
  94
  95                 mov     bx,ax
  96                 mov     ax,0x4400
  97
  98                 int     0x21            // get device info
  99                 jc      error
 100
 101                 and     dx,0x80
 102                 jz      error
 103
 104                 mov     ax,0x4407
 105
 106                 int     0x21            // get status
 107                 jc      error
 108                 or      al,al
 109                 jz      error
 110
 111                 mov     ah,0x3e
 112                 int     0x21            // close handle
 113                 jc      error
 114                 //
 115                 // EMS is good
 116                 //
 117                 mov     emmcfems,1
 118                 jmp End
 119                 error:
 120                 //
 121                 // EMS is bad
 122                 //
 123                 mov     emmcfems,0
 124                 End:
 125         }
 126         return(emmcfems);
 127 }
 128
 129
 130 /*
 131 ======================
 132 =
 133 = MML_SetupEMS
 134 =
 135 =======================
 136 */
 137
 138 byte MML_SetupEMS(mminfo_t *mm)
 139 {
 140         byte    str[160];
 141         byte    err;
 142         boolean errorflag=false;
 143
 144         unsigned int EMSVer = 0;
 145         //byte  EMS_status;
 146         unsigned        totalEMSpages,freeEMSpages,EMSpageframe,EMSpagesmapped,EMShandle;
 147         totalEMSpages = freeEMSpages = EMSpageframe = EMSpagesmapped = 0;
 148
 149         __asm
 150                 {
 151                 mov     ah,EMS_STATUS
 152                 int     EMS_INT                                         // make sure EMS hardware is present
 153                 or      ah,ah
 154                 //mov   [EMS_status],ah
 155                 jnz     error
 156
 157                 mov     ah,EMS_VERSION
 158                 int     EMS_INT
 159                 or      ah,ah
 160                 jnz     error
 161                 mov     [EMSVer],ax                             //      set EMSVer
 162                 cmp     al,0x32                                         // only work on ems 3.2 or greater
 163                 jb      error
 164
 165                 mov     ah,EMS_GETFRAME
 166                 int     EMS_INT                                         // find the page frame address
 167                 or      ah,ah
 168                 jnz     error
 169                 mov     [EMSpageframe],bx
 170
 171                 mov     ah,EMS_GETPAGES
 172                 int     EMS_INT                                         // find out how much EMS is there
 173                 or      ah,ah
 174                 jnz     error
 175                 mov     [totalEMSpages],dx
 176                 mov     [freeEMSpages],bx
 177                 or      bx,bx
 178                 jz      noEMS                                           // no EMS at all to allocate
 179                                                                                         //EXPAND DONG!!!!
 180                 cmp     [EMSVer],0x40
 181                 jb      low
 182                 cmp     bx,[freeEMSpages]
 183                 jle     getpages
 184                 mov     bx,[freeEMSpages]
 185                 jmp     getpages
 186
 187 low:
 188                 cmp     bx,4
 189                 jle     getpages                                        // there is only 1,2,3,or 4 pages
 190                 mov     bx,4                                            // we can't use more than 4 pages
 191
 192 getpages:
 193                 mov     [EMSpagesmapped],bx
 194                 mov     ah,EMS_ALLOCPAGES                       // allocate up to 64k of EMS
 195                 int     EMS_INT
 196                 or      ah,ah
 197                 jnz     error
 198                 mov     [EMShandle],dx
 199                 jmp End
 200 error:
 201                 mov     err,ah
 202                 mov     errorflag,1
 203                 jmp End
 204 noEMS:
 205 End:
 206         }
 207         if(errorflag==true)
 208         {
 209                 //err = CPURegs.h.ah;
 210                 strcpy(str,"MM_SetupEMS: EMS error ");
 211                 //itoa(err,str2,16);
 212                 MM_EMSerr(&str, err);
 213                 printf("%s\n",str);
 214                 return err;
 215         }
 216         mm->totalEMSpages=totalEMSpages;
 217         mm->freeEMSpages=freeEMSpages;
 218         mm->EMSpageframe=EMSpageframe;
 219         mm->EMSpagesmapped=EMSpagesmapped;
 220         mm->EMShandle=EMShandle;
 221         mm->EMSVer=EMSVer;
 222         return 0;
 223 }
 224
 225
 226 /*
 227 ======================
 228 =
 229 = MML_ShutdownEMS
 230 =
 231 =======================
 232 */
 233
 234 void MML_ShutdownEMS(mminfo_t *mm)
 235 {
 236         boolean errorflag=false;
 237         unsigned EMShandle=mm->EMShandle;
 238
 239         if(!EMShandle)
 240                 return;
 241         __asm
 242         {
 243                 mov     ah,EMS_FREEPAGES
 244                 mov     dx,[EMShandle]
 245                 int     EMS_INT
 246                 or      ah,ah
 247                 jz      ok
 248                 mov     errorflag,1
 249                 ok:
 250         }
 251         if(errorflag==true) printf("MML_ShutdownEMS: Error freeing EMS!\n");    //++++ add something
 252 }
 253
 254 /*
 255 ====================
 256 =
 257 = MM_MapEMS
 258 =
 259 = Maps the 64k of EMS used by memory manager into the page frame
 260 = for general use.  This only needs to be called if you are keeping
 261 = other things in EMS.
 262 =
 263 ====================
 264 */
 265
 266 byte MM_MapEMS(mminfo_t *mm, mminfotype *mmi)
 267 {
 268         byte    str[160];
 269         unsigned        EMShandle;
 270         byte err;
 271         boolean errorflag=false;
 272         int     i;
 273         EMShandle=mm->EMShandle;
 274
 275         for (i=0;i<4/*MAPPAGES*/;i++)
 276         {
 277                 __asm
 278                 {
 279                         mov     ah,EMS_MAPPAGE
 280                         mov     bx,[i]                  // logical page
 281                         mov     al,bl                   // physical page
 282                         mov     dx,[EMShandle]  // handle
 283                         int     EMS_INT
 284                         or      ah,ah
 285                         jnz     error
 286                         jmp End
 287                         error:
 288                         mov     err,ah
 289                         mov     errorflag,1
 290                         End:
 291                 }
 292                 if(errorflag==true)
 293                 {
 294                         //err = CPURegs.h.ah;
 295                         strcpy(str,"MM_MapEMS: EMS error ");
 296                         //itoa(err,str2,16);
 297                         MM_EMSerr(str, err);
 298                         printf("%s\n",str);
 299                         //printf("FACK! %x\n", err);
 300                         return err;
 301                 }
 302         }
 303         mmi->EMSmem = (i)*0x4000lu;
 304         return 0;
 305 }
 306
 307 byte MM_MapXEMS(mminfo_t *mm, mminfotype *mmi)
 308 {
 309 //SUB EMS.MapXPages (PhysicalStart, LogicalStart, NumPages, Handle)
 310
 311         //Maps up to 4 logical EMS pages to physical pages in the page frame, where:
 312         //PhysicalStart = Physical page first logical page is mapped to
 313         //LogicalStart  = First logical page to map
 314         //NumPages      = Number of pages to map (1 to 4)
 315         //Handle        = EMS handle logical pages are allocated to
 316
 317   /*//Create a buffer containing the page information
 318 //  FOR x = 0 TO NumPages - 1
 319 //    MapInfo$ = MapInfo$ + MKI$(LogicalStart + x) + MKI$(PhysicalStart + x)
 320 //  NEXT*/
 321
 322 //  Regs.ax = 0x5000                           //Map the pages in the buffer
 323 //  Regs.cx = NumPages                         //to the pageframe
 324 //  Regs.dx = Handle
 325 //  Regs.ds = VARSEG(MapInfo$)
 326 //  Regs.si = SADD(MapInfo$)
 327 //  InterruptX 0x67, Regs, Regs
 328 //      EMS.Error = (Regs.ax AND 0xFF00&) \ 0x100  //Store the status code
 329
 330 //END SUB
 331         byte    str[160];
 332         byte err;
 333         word    EMShandle;
 334         boolean errorflag=false;
 335         int     i;
 336         EMShandle=mm->EMShandle;
 337
 338         if(mm->EMSVer<0x40)
 339                 return 5;
 340
 341         for (i=0;i<MAPPAGES;i++)
 342         {
 343                 __asm
 344                 {
 345                         mov     ah,EMS_MAPXPAGE
 346                         mov     cx,[i]                  // logical page
 347                         mov     al,bl                   // physical page
 348                         mov     dx,[EMShandle]  // handle
 349                         int     EMS_INT
 350                         or      ah,ah
 351                         jnz     error
 352                         jmp End
 353                         error:
 354                         mov     err,ah
 355                         mov     errorflag,1
 356                         End:
 357                 }
 358                 if(errorflag==true)
 359                 {
 360                         //err = CPURegs.h.ah;
 361                         //strcpy(str,"MM_MapXEMS: EMS error 0x");
 362                         strcpy(str,"MM_MapXEMS: EMS error ");
 363                         //itoa(err,str2,16);
 364                         MM_EMSerr(&str, err);
 365                         printf("%s\n",str);
 366                         //printf("%s%x\n",str, err);
 367                         //printf("FACK! %x\n", err);
 368                         return err;
 369                 }
 370         }
 371         mmi->EMSmem = (i)*0x4000lu;
 372         return 0;
 373 }
 374
 375 //==========================================================================
 376
 377 /*
 378 ======================
 379 =
 380 = MML_CheckForXMS
 381 =
 382 = Check for XMM driver
 383 =
 384 =======================
 385 */
 386
 387 boolean MML_CheckForXMS(mminfo_t *mm)
 388 {
 389         boolean errorflag=false;
 390         mm->numUMBs = 0;
 391
 392         __asm
 393         {
 394                 mov     ax,0x4300
 395                 int     0x2f                            // query status of installed diver
 396                 cmp     al,0x80
 397                 je      good
 398                 mov     errorflag,1
 399                 good:
 400         }
 401         if(errorflag==true) return false;
 402         else return true;
 403 }
 404
 405
 406 /*
 407 ======================
 408 =
 409 = MML_SetupXMS
 410 =
 411 = Try to allocate all upper memory block
 412 =
 413 =======================
 414 */
 415
 416 void MML_SetupXMS(mminfo_t *mm, mminfotype *mmi)
 417 {
 418         unsigned        base,size;
 419
 420 getmemory:
 421         __asm
 422         {
 423                 mov     ax,0x4310
 424                 int     0x2f
 425                 mov     [WORD PTR XMSaddr],bx
 426                 mov     [WORD PTR XMSaddr+2],es         // function pointer to XMS driver
 427
 428                 mov     ah,XMS_ALLOCUMB
 429                 mov     dx,0xffff                                       // try for largest block possible
 430                 //mov     ax,dx                                         // Set available Kbytes.
 431                 call    [DWORD PTR XMSaddr]
 432                 or      ax,ax
 433                 jnz     gotone
 434
 435                 cmp     bl,0xb0                                         // error: smaller UMB is available
 436                 jne     done;
 437
 438                 mov     ah,XMS_ALLOCUMB
 439                 call    [DWORD PTR XMSaddr]             // DX holds largest available UMB
 440                 or      ax,ax
 441                 jz      done                                            // another error...
 442
 443 gotone:
 444                 mov     [base],bx
 445                 mov     [size],dx
 446 done:
 447         }
 448         printf("base=%u ", base); printf("size=%u\n", size);
 449         MML_UseSpace(base,size, mm);
 450         mmi->XMSmem += size*16;
 451         mm->UMBbase[mm->numUMBs] = base;
 452         mm->numUMBs++;
 453         if(mm->numUMBs < MAXUMBS)
 454                 goto getmemory;
 455 }
 456
 457
 458 /*
 459 ======================
 460 =
 461 = MML_ShutdownXMS
 462 =
 463 ======================
 464 */
 465
 466 void MML_ShutdownXMS(mminfo_t *mm)
 467 {
 468         int     i;
 469         unsigned        base;
 470
 471         for (i=0;i<mm->numUMBs;i++)
 472         {
 473                 base = mm->UMBbase[i];
 474                 __asm
 475                 {
 476                         mov     ah,XMS_FREEUMB
 477                         mov     dx,[base]
 478                         call    [DWORD PTR XMSaddr]
 479                 }
 480         }
 481 }
 482
 483 //==========================================================================
 484
 485 /*
 486 ======================
 487 =
 488 = MML_UseSpace
 489 =
 490 = Marks a range of paragraphs as usable by the memory manager
 491 = This is used to mark space for the near heap, far heap, ems page frame,
 492 = and upper memory blocks
 493 =
 494 ======================
 495 */
 496
 497 void MML_UseSpace(/*d*/word segstart, dword seglength, mminfo_t *mm)
 498 {
 499         mmblocktype huge *scan,huge *last;
 500         word            segm;
 501         dword   oldend;
 502         dword           extra;
 503
 504         scan = last = mm->mmhead;
 505         mm->mmrover = mm->mmhead;               // reset rover to start of memory
 506
 507 //
 508 // search for the block that contains the range of segments
 509 //
 510         while(scan->start+scan->length < segstart)
 511         {
 512                 last = scan;
 513                 scan = scan->next;
 514         }
 515
 516         //find out how many blocks it spans!
 517         if(seglength>0xffffu)
 518         {
 519 //              segm=seglength/0x4000u;
 520                 segm=seglength/0xffffu;
 521         }
 522         else segm=1;
 523
 524         //++++emsver stuff!
 525         if(segm>1/*extra>0xfffflu*/)
 526         {
 527                 /*__asm
 528                 {
 529                         push    ds
 530                         mov     ax,ds
 531                         inc             ax
 532                         mov     ds,ax
 533                 }*/
 534
 535
 536 //MML_UseSpace(?segstart?, ?length?, mm);
 537
 538                 /*__asm
 539                 {
 540                         pop ds
 541                 }*/
 542                 //printf("MML_UseSpace: Segment spans two blocks!\n");
 543         }
 544
 545 //
 546 // take the given range out of the block
 547 //
 548         oldend = scan->start + scan->length;
 549         extra = oldend - (segstart+seglength);
 550 /*
 551 printf("segm=%u ", segm);
 552 printf("ex=%lu  ", extra);
 553 printf("start+seglen=%lu        ", segstart+seglength);
 554 printf("len=%u  ", scan->length);
 555 printf("segsta=%x       ", segstart);
 556 printf("seglen=%lu\n", seglength);
 557 */
 558 //segu:
 559 //++++todo: linked list of segment!
 560 //printf("segm=%lu\n", segm);
 561         if(segstart == scan->start)
 562         {
 563                 last->next = scan->next;                        // unlink block
 564                 MM_FreeBlock(scan, mm);
 565                 scan = last;
 566         }
 567         else
 568                 scan->length = segstart-scan->start;    // shorten block
 569
 570 //      segm--;
 571
 572         if(extra > 0)
 573         {
 574                 MM_GetNewBlock(mm);
 575                 mm->mmnew->next = scan->next;
 576                 scan->next = mm->mmnew;
 577                 mm->mmnew->start = segstart+seglength;
 578                 mm->mmnew->length = extra;
 579                 mm->mmnew->attributes = LOCKBIT;
 580         }//else if(segm>0) goto segu;
 581
 582 }
 583
 584 //==========================================================================
 585
 586 /*
 587 ====================
 588 =
 589 = MML_ClearBlock
 590 =
 591 = We are out of blocks, so free a purgable block
 592 =
 593 ====================
 594 */
 595
 596 void MML_ClearBlock(mminfo_t *mm)
 597 {
 598         mmblocktype huge *scan,huge *last;
 599
 600         scan = mm->mmhead->next;
 601
 602         while(scan)
 603         {
 604                 if(!(scan->attributes&LOCKBIT) && (scan->attributes&PURGEBITS))
 605                 {
 606                         MM_FreePtr(scan->useptr, mm);
 607                         return;
 608                 }
 609                 scan = scan->next;
 610         }
 611
 612         printf("MM_ClearBlock: No purgable blocks!\n");
 613 }
 614
 615
 616 //==========================================================================
 617
 618 /*
 619 ===================
 620 =
 621 = MM_Startup
 622 =
 623 = Grabs all space from turbo with malloc/farmalloc
 624 = Allocates bufferseg misc buffer
 625 =
 626 ===================
 627 */
 628
 629 void MM_Startup(mminfo_t *mm, mminfotype *mmi)
 630 {
 631         int i;
 632         dword length;
 633         void huge       *start;
 634         unsigned        segstart,seglength,endfree;
 635
 636         if(mm->mmstarted)
 637                 MM_Shutdown(mm);
 638
 639         mm->mmstarted = true;
 640         mm->bombonerror = true;
 641 //
 642 // set up the linked list (everything in the free list;
 643 //
 644 //      printf("                linked list making!\n");
 645         mm->mmhead = NULL;
 646         mm->mmfree = &(mm->mmblocks[0]);
 647         for(i=0;i<MAXBLOCKS-1;i++)
 648         {
 649                 mm->mmblocks[i].next = &(mm->mmblocks[i+1]);
 650         }
 651         mm->mmblocks[i].next = NULL;
 652
 653 //
 654 // locked block of all memory until we punch out free space
 655 //
 656 //      printf("                newblock making!\n");
 657         MM_GetNewBlock(mm);
 658         mm->mmhead = mm->mmnew;                         // this will allways be the first node
 659         mm->mmnew->start = 0;
 660         mm->mmnew->length = 0xffff;
 661         mm->mmnew->attributes = LOCKBIT;
 662         mm->mmnew->next = NULL;
 663         mm->mmrover = mm->mmhead;
 664
 665 //
 666 // get all available near conventional memory segments
 667 //
 668         printf("                nearheap making!\n");
 669 //----  length=coreleft();
 670         //_nheapgrow();
 671         length=_memmax();
 672         //printf("      %u\n", length);
 673         start = (void huge *)(mm->nearheap = _nmalloc(length));
 674         length -= 16-(FP_OFF(start)&15);
 675         length -= SAVENEARHEAP;
 676         seglength = length / 16;                        // now in paragraphs
 677         segstart = FP_SEG(start)+(FP_OFF(start)+15)/16;
 678         MML_UseSpace(segstart,seglength, mm);
 679         mmi->nearheap = length;
 680         /*switch( _nheapchk() ) {
 681                 case _HEAPOK:
 682                         printf( "OK - nearheap is good\n" );
 683                 break;
 684                 case _HEAPEMPTY:
 685                         printf( "OK - nearheap is empty\n" );
 686                 break;
 687                 case _HEAPBADBEGIN:
 688                         printf( "ERROR - nearheap is damaged\n" );
 689                 break;
 690                 case _HEAPBADNODE:
 691                         printf( "ERROR - bad node in nearheap\n" );
 692                 break;
 693         }*/
 694 //      printf("                near heap ok!\n");
 695
 696 //
 697 // get all available far conventional memory segments
 698 //
 699 //----  length=farcoreleft();
 700         printf("                farheap making!\n");
 701         _fheapgrow();
 702         length=0xffffUL*4UL;//_memavl();
 703         start = mm->farheap = halloc(length, sizeof(byte));
 704         //start = mm->farheap = _fmalloc(length);
 705         length -= 16-(FP_OFF(start)&15);
 706         length -= SAVEFARHEAP;
 707         seglength = length / 16;                        // now in paragraphs
 708         segstart = FP_SEG(start)+(FP_OFF(start)+15)/16;
 709         MML_UseSpace(segstart,seglength, mm);
 710         mmi->farheap = length;
 711         mmi->mainmem = mmi->nearheap + mmi->farheap;
 712         /*switch( _fheapchk() ) {
 713                 case _HEAPOK:
 714                         printf( "OK - farheap is good\n" );
 715                 break;
 716                 case _HEAPEMPTY:
 717                         printf( "OK - farheap is empty\n" );
 718                 break;
 719                 case _HEAPBADBEGIN:
 720                         printf( "ERROR - farheap is damaged\n" );
 721                 break;
 722                 case _HEAPBADNODE:
 723                         printf( "ERROR - bad node in farheap\n" );
 724                 break;
 725         }*/
 726         //printf("              far heap ok!\n");
 727
 728 //
 729 // detect EMS and allocate up to 64K at page frame
 730 //
 731 printf("                EMS1\n");
 732 printf("\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");     //bug!
 733         mmi->EMSmem = 0;
 734         for(i = 1;i < __argc;i++)
 735         {
 736                 if(US_CheckParm(__argv[i],ParmStringsexmm) == 0)
 737                         goto emsskip;                           // param NOEMS
 738         }
 739 printf("\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");     //bug!
 740         if(MML_CheckForEMS())
 741         {
 742 printf("                EMS2\n");
 743 printf("\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");     //bug!
 744                 MML_SetupEMS(mm);                                       // allocate space
 745 printf("                EMS3\n");
 746 printf("\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");     //bug!
 747                 //TODO: EMS4! AND EMS 3.2 MASSIVE DATA HANDLMENT!
 748                 MML_UseSpace(mm->EMSpageframe,(MAPPAGES)*0x4000lu, mm);
 749 printf("\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");     //bug!
 750 printf("                EMS4\n");
 751                 //if(mm->EMSVer<0x40)
 752                         MM_MapEMS(mm, mmi);                                     // map in used pages
 753                 //else
 754                         //MM_MapXEMS(mm, mmi);                                  // map in used pages
 755         }
 756
 757 //
 758 // detect XMS and get upper memory blocks
 759 //
 760 emsskip:
 761         mmi->XMSmem = 0;
 762         for(i = 1;i < __argc;i++)
 763         {
 764                 if(US_CheckParm(__argv[i],ParmStringsexmm) == 0)
 765                         goto xmsskip;                           // param NOXMS
 766         }
 767 printf("\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");     //bug!
 768         if(MML_CheckForXMS(mm))
 769         {
 770 printf("\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");     //bug!
 771 printf("                XMS!\n");
 772                 //++++          MML_SetupXMS(mm, mmi);                                  // allocate as many UMBs as possible
 773         }
 774
 775 //
 776 // allocate the misc buffer
 777 //
 778 xmsskip:
 779         mm->mmrover = mm->mmhead;               // start looking for space after low block
 780
 781         MM_GetPtr(&(mm->bufferseg),BUFFERSIZE, mm, mmi);
 782 }
 783
 784 //==========================================================================
 785
 786 /*
 787 ====================
 788 =
 789 = MM_Shutdown
 790 =
 791 = Frees all conventional, EMS, and XMS allocated
 792 =
 793 ====================
 794 */
 795
 796 void MM_Shutdown(mminfo_t *mm)
 797 {
 798         if(!(mm->mmstarted))
 799                 return;
 800
 801         _ffree(mm->farheap);
 802         printf("                far freed\n");
 803         free(mm->nearheap);
 804         printf("                near freed\n");
 805         //hfree(mm->hugeheap);
 806         //printf("huge freed\n");
 807         if(MML_CheckForEMS()){ MML_ShutdownEMS(mm); printf("            EMS freed\n"); }
 808         if(MML_CheckForXMS(mm)){ MML_ShutdownXMS(mm); printf("          XMS freed\n"); }
 809 }
 810
 811 //==========================================================================
 812
 813 /*
 814 ====================
 815 =
 816 = MM_GetPtr
 817 =
 818 = Allocates an unlocked, unpurgable block
 819 =
 820 ====================
 821 */
 822
 823 void MM_GetPtr(memptr *baseptr,dword size, mminfo_t *mm, mminfotype *mmi)
 824 {
 825         mmblocktype huge *scan,huge *lastscan,huge *endscan,huge *purge,huge *next;
 826         int                     search;
 827         unsigned        needed,startseg;
 828
 829         needed = (size+15)/16;          // convert size from bytes to paragraphs
 830
 831         MM_GetNewBlock(mm);                             // fill in start and next after a spot is found
 832         mm->mmnew->length = needed;
 833         mm->mmnew->useptr = baseptr;
 834         mm->mmnew->attributes = BASEATTRIBUTES;
 835
 836         for(search = 0; search<3; search++)
 837         {
 838         //
 839         // first search:        try to allocate right after the rover, then on up
 840         // second search:       search from the head pointer up to the rover
 841         // third search:        compress memory, then scan from start
 842                 if(search == 1 && mm->mmrover == mm->mmhead)
 843                         search++;
 844
 845                 switch(search)
 846                 {
 847                 case 0:
 848                         lastscan = mm->mmrover;
 849                         scan = mm->mmrover->next;
 850                         endscan = NULL;
 851                         break;
 852                 case 1:
 853                         lastscan = mm->mmhead;
 854                         scan = mm->mmhead->next;
 855                         endscan = mm->mmrover;
 856                         break;
 857                 case 2:
 858                         MM_SortMem(mm);
 859                         lastscan = mm->mmhead;
 860                         scan = mm->mmhead->next;
 861                         endscan = NULL;
 862                         break;
 863                 }
 864
 865                 startseg = lastscan->start + lastscan->length;
 866
 867                 while(scan != endscan)
 868                 {
 869                         if(scan->start - startseg >= needed)
 870                         {
 871                         //
 872                         // got enough space between the end of lastscan and
 873                         // the start of scan, so throw out anything in the middle
 874                         // and allocate the new block
 875                         //
 876                                 purge = lastscan->next;
 877                                 lastscan->next = mm->mmnew;
 878                                 mm->mmnew->start = *(unsigned *)baseptr = startseg;
 879                                 mm->mmnew->next = scan;
 880                                 while(purge != scan)
 881                                 {       // free the purgable block
 882                                         next = purge->next;
 883                                         MM_FreeBlock(purge, mm);
 884                                         purge = next;           // purge another if not at scan
 885                                 }
 886                                 mm->mmrover = mm->mmnew;
 887                                 return; // good allocation!
 888                         }
 889
 890                         //
 891                         // if this block is purge level zero or locked, skip past it
 892                         //
 893                         if((scan->attributes & LOCKBIT)
 894                                 || !(scan->attributes & PURGEBITS) )
 895                         {
 896                                 lastscan = scan;
 897                                 startseg = lastscan->start + lastscan->length;
 898                         }
 899
 900
 901                         scan=scan->next;                // look at next line
 902                 }
 903         }
 904
 905         if (mm->bombonerror)
 906                 printf(OUT_OF_MEM_MSG,(size-mmi->nearheap));
 907         else
 908                 mm->mmerror = true;
 909 }
 910
 911 //==========================================================================
 912
 913 /*
 914 ====================
 915 =
 916 = MM_FreePtr
 917 =
 918 = Allocates an unlocked, unpurgable block
 919 =
 920 ====================
 921 */
 922
 923 void MM_FreePtr(memptr *baseptr, mminfo_t *mm)
 924 {
 925         mmblocktype huge *scan,huge *last;
 926
 927         last = mm->mmhead;
 928         scan = last->next;
 929
 930         if(baseptr == mm->mmrover->useptr)      // removed the last allocated block
 931                 mm->mmrover = mm->mmhead;
 932
 933         while(scan->useptr != baseptr && scan)
 934         {
 935                 last = scan;
 936                 scan = scan->next;
 937         }
 938
 939         if(!scan)
 940         {
 941                 printf("MM_FreePtr: Block not found!\n");
 942                 return;
 943         }
 944
 945         last->next = scan->next;
 946
 947         MM_FreeBlock(scan, mm);
 948 }
 949 //==========================================================================
 950
 951 /*
 952 =====================
 953 =
 954 = MM_SetPurge
 955 =
 956 = Sets the purge level for a block (locked blocks cannot be made purgable)
 957 =
 958 =====================
 959 */
 960
 961 void MM_SetPurge(memptr *baseptr, int purge, mminfo_t *mm)
 962 {
 963         mmblocktype huge *start;
 964
 965         start = mm->mmrover;
 966
 967         do
 968         {
 969                 if(mm->mmrover->useptr == baseptr)
 970                         break;
 971
 972                 mm->mmrover = mm->mmrover->next;
 973
 974                 if(!mm->mmrover)
 975                         mm->mmrover = mm->mmhead;
 976                 else if(mm->mmrover == start)
 977                 {
 978                         printf("MM_SetPurge: Block not found!");
 979                         return;
 980                 }
 981
 982         } while(1);
 983
 984         mm->mmrover->attributes &= ~PURGEBITS;
 985         mm->mmrover->attributes |= purge;
 986 }
 987
 988 //==========================================================================
 989
 990 /*
 991 =====================
 992 =
 993 = MM_SetLock
 994 =
 995 = Locks / unlocks the block
 996 =
 997 =====================
 998 */
 999
1000 void MM_SetLock(memptr *baseptr, boolean locked, mminfo_t *mm)
1001 {
1002         mmblocktype huge *start;
1003
1004         start = mm->mmrover;
1005
1006         do
1007         {
1008                 if(mm->mmrover->useptr == baseptr)
1009                         break;
1010
1011                 mm->mmrover = mm->mmrover->next;
1012
1013                 if(!mm->mmrover)
1014                         mm->mmrover = mm->mmhead;
1015                 else if(mm->mmrover == start)
1016                 {
1017                         printf("MM_SetLock: Block not found!");
1018                         return;
1019                 }
1020
1021         } while(1);
1022
1023         mm->mmrover->attributes &= ~LOCKBIT;
1024         mm->mmrover->attributes |= locked*LOCKBIT;
1025 }
1026
1027 //==========================================================================
1028
1029 /*
1030 =====================
1031 =
1032 = MM_SortMem
1033 =
1034 = Throws out all purgable stuff and compresses movable blocks
1035 =
1036 =====================
1037 */
1038
1039 void MM_SortMem(mminfo_t *mm)
1040 {
1041         mmblocktype huge *scan,huge *last,huge *next;
1042         unsigned        start,length,source,dest,oldborder;
1043         int                     playing;
1044
1045         //
1046         // lock down a currently playing sound
1047         //
1048 /*++++  playing = SD_SoundPlaying ();
1049         if(playing)
1050         {
1051                 switch (SoundMode)
1052                 {
1053                 case sdm_PC:
1054                         playing += STARTPCSOUNDS;
1055                         break;
1056                 case sdm_AdLib:
1057                         playing += STARTADLIBSOUNDS;
1058                         break;
1059                 }
1060                 MM_SetLock(&(memptr)audiosegs[playing],true);
1061         }
1062
1063
1064         SD_StopSound();*/
1065 //      oldborder = bordercolor;
1066 //      VW_ColorBorder (15);
1067
1068         if(beforesort)
1069                 beforesort();
1070
1071         scan = mm->mmhead;
1072
1073         last = NULL;            // shut up compiler warning
1074
1075         while(scan)
1076         {
1077                 if(scan->attributes & LOCKBIT)
1078                 {
1079                 //
1080                 // block is locked, so try to pile later blocks right after it
1081                 //
1082                         start = scan->start + scan->length;
1083                 }
1084                 else
1085                 {
1086                         if(scan->attributes & PURGEBITS)
1087                         {
1088                         //
1089                         // throw out the purgable block
1090                         //
1091                                 next = scan->next;
1092                                 MM_FreeBlock(scan, mm);
1093                                 last->next = next;
1094                                 scan = next;
1095                                 continue;
1096                         }
1097                         else
1098                         {
1099                         //
1100                         // push the non purgable block on top of the last moved block
1101                         //
1102                                 if(scan->start != start)
1103                                 {
1104                                         length = scan->length;
1105                                         source = scan->start;
1106                                         dest = start;
1107                                         while(length > 0xf00)
1108                                         {
1109                                                 movedata(source,0,dest,0,0xf00*16);
1110                                                 length -= 0xf00;
1111                                                 source += 0xf00;
1112                                                 dest += 0xf00;
1113                                         }
1114                                         movedata(source,0,dest,0,length*16);
1115
1116                                         scan->start = start;
1117                                         *(unsigned *)scan->useptr = start;
1118                                 }
1119                                 start = scan->start + scan->length;
1120                         }
1121                 }
1122
1123                 last = scan;
1124                 scan = scan->next;              // go to next block
1125         }
1126
1127         mm->mmrover = mm->mmhead;
1128
1129         if(aftersort)
1130                 aftersort();
1131
1132 //      VW_ColorBorder (oldborder);
1133
1134 /*++++  if(playing)
1135                 MM_SetLock(&(memptr)audiosegs[playing],false);*/
1136 }
1137
1138
1139 //==========================================================================
1140
1141 //****#if 0
1142 /*
1143 =====================
1144 =
1145 = MM_ShowMemory
1146 =
1147 =====================
1148 */
1149
1150 void MM_ShowMemory(page_t *page, mminfo_t *mm)
1151 {
1152         mmblocktype huge *scan;
1153         word color,temp;
1154         long    end,owner;
1155         word chx,chy;
1156         byte    scratch[160],str[16];
1157
1158 //****  VW_SetDefaultColors();
1159 //****  VW_SetLineWidth(40);
1160 //++++mh        temp = bufferofs;
1161 //++++mh        bufferofs = 0;
1162 //****  VW_SetScreen (0,0);
1163
1164         scan = mm->mmhead;
1165
1166         end = -1;
1167
1168 CA_OpenDebug ();
1169
1170         chx=0;
1171         chy=0;
1172
1173         while(scan)
1174         {
1175                 if(scan->attributes & PURGEBITS)
1176                         color = 5;              // dark purple = purgable
1177                 else
1178                         color = 9;              // medium blue = non purgable
1179                 if(scan->attributes & LOCKBIT)
1180                         color = 12;             // red = locked
1181                 if(scan->start<=end)
1182                 {
1183                         //printf(");
1184                         write(debughandle,"\nMM_ShowMemory: Memory block order currupted!\n",strlen("\nMM_ShowMemory: Memory block order currupted!\n"));
1185                         //modexprint(&page, chx, chy, 1, 0, 24, "\nMM_ShowMemory: Memory block order currupted!\n");
1186                         return;
1187                 }
1188                 end = scan->start+scan->length-1;
1189                 chy = scan->start/320;
1190                 chx = scan->start%320;
1191                                 //modexhlin(page, scan->start, (unsigned)end, chy, color);
1192                                 //for(chx=scan->start;chx+4>=(word)end;chx+=4)
1193                                 //{
1194                                         modexClearRegion(page, chx, chy, 4, 4, color);
1195                                 //}
1196
1197 //++++          VW_Hlin(scan->start,(unsigned)end,0,color);
1198
1199 //++++          VW_Plot(scan->start,0,15);
1200                                 modexClearRegion(page, chx, chy, 4, 4, 15);
1201                 if(scan->next->start > end+1)
1202 //++++                  VW_Hlin(end+1,scan->next->start,0,0);   // black = free
1203                         //for(chx=scan->next->start;chx+4>=(word)end+1;chx+=4)
1204                         //{
1205                                 chx+=scan->next->start;
1206                                 modexClearRegion(page, chx, chy, 4, 4, 2);
1207                         //}
1208                                         //modexhlin(page, end+1,scan->next->start, chy, 0);
1209
1210 /*
1211                 end = scan->length-1;
1212                 y = scan->start/320;
1213                 x = scan->start%320;
1214                 VW_Hlin(x,x+end,y,color);
1215                 VW_Plot(x,y,15);
1216                 if (scan->next && scan->next->start > end+1)
1217                         VW_Hlin(x+end+1,x+(scan->next->start-scan->start),y,0); // black = free
1218 */
1219
1220 //****#if 0
1221 printf("\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");     //bug!
1222 strcpy(scratch,"Seg:");
1223 ultoa (scan->start,str,16);
1224 strcat (scratch,str);
1225 strcat (scratch,"\tSize:");
1226 ltoa ((dword)scan->length*16,str,10);
1227 strcat (scratch,str);
1228 strcat (scratch,"\tOwner:0x");
1229 owner = (unsigned)scan->useptr;
1230 ultoa (owner,str,16);
1231 strcat (scratch,str);
1232 strcat (scratch,"\n");
1233 write(debughandle,scratch,strlen(scratch));
1234 //modexprint(page, chx, chy, 1, 0, 24, &scratch);
1235 chy+=4;
1236 //fprintf(stdout, "%s", scratch);
1237 //****#endif
1238
1239                 scan = scan->next;
1240         }
1241
1242 CA_CloseDebug ();
1243
1244 //++++mh        IN_Ack();
1245 //****  VW_SetLineWidth(64);
1246 //++++mh        bufferofs = temp;
1247 }
1248 //****#endif
1249
1250 //==========================================================================
1251
1252 /*
1253 =====================
1254 =
1255 = MM_DumpData
1256 =
1257 =====================
1258 */
1259
1260 void MM_DumpData(mminfo_t *mm)
1261 {
1262         mmblocktype far *scan,far *best;
1263         long    lowest,oldlowest;
1264         word    owner;
1265         byte    lock,purge;
1266         FILE    *dumpfile;
1267
1268
1269         //++++free(mm->nearheap);
1270         dumpfile = fopen ("mmdump.txt","w");
1271         if (!dumpfile){
1272                 printf("MM_DumpData: Couldn't open MMDUMP.TXT!\n");
1273                 return;
1274         }
1275
1276         lowest = -1;
1277         do
1278         {
1279                 oldlowest = lowest;
1280                 lowest = 0xffff;
1281
1282                 scan = mm->mmhead;
1283                 while (scan)
1284                 {
1285                         owner = (word)scan->useptr;
1286
1287                         if (owner && owner<lowest && owner > oldlowest)
1288                         {
1289                                 best = scan;
1290                                 lowest = owner;
1291                         }
1292
1293                         scan = scan->next;
1294                 }
1295
1296                 if (lowest != 0xffff)
1297                 {
1298                         if (best->attributes & PURGEBITS)
1299                                 purge = 'P';
1300                         else
1301                                 purge = '-';
1302                         if (best->attributes & LOCKBIT)
1303                                 lock = 'L';
1304                         else
1305                                 lock = '-';
1306                         fprintf (dumpfile,"0x%p (%c%c) = %u\n"
1307                         ,(word)lowest,lock,purge,best->length);
1308                 }
1309
1310         } while (lowest != 0xffff);
1311
1312         fclose(dumpfile);
1313         printf("MMDUMP.TXT created.\n");
1314 }
1315
1316 //==========================================================================
1317
1318
1319 /*
1320 ======================
1321 =
1322 = MM_UnusedMemory
1323 =
1324 = Returns the total free space without purging
1325 =
1326 ======================
1327 */
1328
1329 dword MM_UnusedMemory(mminfo_t *mm)
1330 {
1331         dword free;
1332         mmblocktype huge *scan;
1333
1334         free = 0;
1335         scan = mm->mmhead;
1336
1337         while(scan->next)
1338         {
1339                 free += scan->next->start - (scan->start + scan->length);
1340                 scan = scan->next;
1341         }
1342
1343         return free*16l;
1344 //      return free;
1345 }
1346
1347 //==========================================================================
1348
1349
1350 /*
1351 ======================
1352 =
1353 = MM_TotalFree
1354 =
1355 = Returns the total free space with purging
1356 =
1357 ======================
1358 */
1359
1360 dword MM_TotalFree(mminfo_t *mm)
1361 {
1362         dword free;
1363         mmblocktype huge *scan;
1364
1365         free = 0;
1366         scan = mm->mmhead;
1367
1368         while(scan->next)
1369         {
1370                 if((scan->attributes&PURGEBITS) && !(scan->attributes&LOCKBIT))
1371                         free += scan->length;
1372                 free += scan->next->start - (scan->start + scan->length);
1373                 scan = scan->next;
1374         }
1375
1376         return free*16l;
1377 //      return free;
1378 }
1379
1380 //==========================================================================
1381
1382 /*
1383 =====================
1384 =
1385 = MM_Report
1386 =
1387 =====================
1388 */
1389
1390 void MM_Report(page_t *page, mminfo_t *mm, mminfotype *mmi)
1391 {
1392         if(MML_CheckForEMS())
1393         {
1394                 printf("EMM v%x.%x available\n", mm->EMSVer>>4,mm->EMSVer&0x0F);
1395                 printf("totalEMSpages=%u\n", mm->totalEMSpages);
1396                 printf("freeEMSpages=%u\n", mm->freeEMSpages);
1397                 printf("EMSpageframe=%x\n", mm->EMSpageframe);
1398         }
1399         if(MML_CheckForXMS(mm)) printf("XMSaddr=%Fp\n", *XMSaddr);
1400         printf("near=%lu\n", mmi->nearheap);
1401         printf("far=%lu\n", mmi->farheap);
1402         printf("EMSmem=%lu\n", mmi->EMSmem);
1403         printf("XMSmem=%lu\n", mmi->XMSmem);
1404         printf("mainmem=%lu\n", mmi->mainmem);
1405         printf("UnusedMemory=%lu\n", MM_UnusedMemory(mm));
1406         printf("TotalFree=%lu\n", MM_TotalFree(mm));
1407 //      printf("\n");
1408 //      printf("UnusedMemory=%lu kb\n", MM_UnusedMemory()/10248);
1409 //      printf("TotalFree=%lu kb\n", MM_TotalFree()/10248);
1410 }
1411
1412 //==========================================================================
1413
1414 /*
1415 =====================
1416 =
1417 = MM_EMSerr
1418 =
1419 =====================
1420 */
1421
1422 void MM_EMSerr(byte *stri, byte err)
1423 {
1424         //Returns a text string describing the error code in EMS.Error.
1425         switch(err)
1426         {
1427                 case 0x0:
1428                         strcat(stri, "successful");
1429                 break;
1430                 case 0x80:
1431                         strcat(stri, "internal error");
1432                 break;
1433                 case 0x81:
1434                         strcat(stri, "hardware malfunction");
1435                 break;
1436                 case 0x82:
1437                         strcat(stri, "busy .. retry later");
1438                 break;
1439                 case 0x83:
1440                         strcat(stri, "invalid handle");
1441                 break;
1442                 case 0x84:
1443                         strcat(stri, "undefined function requested by application");
1444                 break;
1445                 case 0x85:
1446                         strcat(stri, "no more handles available");
1447                 break;
1448                 case 0x86:
1449                         strcat(stri, "error in save or restore of mapping context");
1450                 break;
1451                 case 0x87:
1452                         strcat(stri, "insufficient memory pages in system");
1453                 break;
1454                 case 0x88:
1455                         strcat(stri, "insufficient memory pages available");
1456                 break;
1457                 case 0x89:
1458                         strcat(stri, "zero pages requested");
1459                 break;
1460                 case 0x8A:
1461                         strcat(stri, "invalid logical page number encountered");
1462                 break;
1463                 case 0x8B:
1464                         strcat(stri, "invalid physical page number encountered");
1465                 break;
1466                 case 0x8C:
1467                         strcat(stri, "page-mapping hardware state save area is full");
1468                 break;
1469                 case 0x8D:
1470                         strcat(stri, "save of mapping context failed");
1471                 break;
1472                 case 0x8E:
1473                         strcat(stri, "restore of mapping context failed");
1474                 break;
1475                 case 0x8F:
1476                         strcat(stri, "undefined subfunction");
1477                 break;
1478                 case 0x90:
1479                         strcat(stri, "undefined attribute type");
1480                 break;
1481                 case 0x91:
1482                         strcat(stri, "feature not supported");
1483                 break;
1484                 case 0x92:
1485                         strcat(stri, "successful, but a portion of the source region has been overwritten");
1486                 break;
1487                 case 0x93:
1488                         strcat(stri, "length of source or destination region exceeds length of region allocated to either source or destination handle");
1489                 break;
1490                 case 0x94:
1491                         strcat(stri, "conventional and expanded memory regions overlap");
1492                 break;
1493                 case 0x95:
1494                         strcat(stri, "offset within logical page exceeds size of logical page");
1495                 break;
1496                 case 0x96:
1497                         strcat(stri, "region length exceeds 1 MB");
1498                 break;
1499                 case 0x97:
1500                         strcat(stri, "source and destination EMS regions have same handle and overlap");
1501                 break;
1502                 case 0x98:
1503                         strcat(stri, "memory source or destination type undefined");
1504                 break;
1505                 case 0x9A:
1506                         strcat(stri, "specified alternate map register or DMA register set not supported");
1507                 break;
1508                 case 0x9B:
1509                         strcat(stri, "all alternate map register or DMA register sets currently allocated");
1510                 break;
1511                 case 0x9C:
1512                         strcat(stri, "alternate map register or DMA register sets not supported");
1513                 break;
1514                 case 0x9D:
1515                         strcat(stri, "undefined or unallocated alternate map register or DMA register set");
1516                 break;
1517                 case 0x9E:
1518                         strcat(stri, "dedicated DMA channels not supported");
1519                 break;
1520                 case 0x9F:
1521                         strcat(stri, "specified dedicated DMA channel not supported");
1522                 break;
1523                 case 0xA0:
1524                         strcat(stri, "no such handle name");
1525                 break;
1526                 case 0xA1:
1527                         strcat(stri, "a handle found had no name, or duplicate handle name");
1528                 break;
1529                 case 0xA2:
1530                         strcat(stri, "attempted to wrap around 1M conventional address space");
1531                 break;
1532                 case 0xA3:
1533                         strcat(stri, "source array corrupted");
1534                 break;
1535                 case 0xA4:
1536                         strcat(stri, "operating system denied access");
1537                 break;
1538                 default:
1539                         strcat(stri, "undefined error");
1540         }
1541 }
1542
1543 //==========================================================================
1544
1545 /*
1546 =====================
1547 =
1548 = MM_BombOnError
1549 =
1550 =====================
1551 */
1552
1553 void MM_BombOnError(boolean bomb, mminfo_t *mm)
1554 {
1555         mm->bombonerror = bomb;
1556 }
1557
1558 void MM_GetNewBlock(mminfo_t *mm)
1559 {
1560         if(!mm->mmfree)
1561                 MML_ClearBlock(mm);
1562         mm->mmnew=mm->mmfree;
1563         mm->mmfree=mm->mmfree->next;
1564         /*if(!(mm->mmnew=mm->mmfree))
1565         {
1566                 printf("MM_GETNEWBLOCK: No free blocks!");
1567                 return;
1568         }
1569         mm->mmfree=mm->mmfree->next;*/
1570 }
1571
1572 void MM_FreeBlock(mmblocktype *x, mminfo_t *mm)
1573 {
1574         x->useptr=NULL;
1575         x->next=mm->mmfree;
1576         mm->mmfree=x;
1577 }
1578
1579 void MM_seguin(void)
1580 {
1581         __asm
1582         {
1583                 push    ds
1584                 mov     ax,ds
1585                 inc             ax
1586                 mov     ds,ax
1587         }
1588 }
1589
1590 void MM_segude(void)
1591 {
1592         __asm
1593         {
1594                 pop ds
1595         }
1596 }
1597
1598 /*
1599 pull data from far and put it into ds var
1600 mov ax,es:si
1601 mov x,ax
1602 */
1603 /*
1604 ss stack segment
1605 sp top of stack
1606 bp bottem of stack
1607 */