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         char    emmname[] = "EMMXXXX0";
  87 //              mov     dx,OFFSET emmname
  88         __asm {
  89                 LEA     DX, emmname     //fix by andrius4669
  90                 mov     ax,0x3d00
  91                 int     0x21            // try to open EMMXXXX0 device
  92                 jc      error
  93
  94                 mov     bx,ax
  95                 mov     ax,0x4400
  96
  97                 int     0x21            // get device info
  98                 jc      error
  99
 100                 and     dx,0x80
 101                 jz      error
 102
 103                 mov     ax,0x4407
 104
 105                 int     0x21            // get status
 106                 jc      error
 107                 or      al,al
 108                 jz      error
 109
 110                 mov     ah,0x3e
 111                 int     0x21            // close handle
 112                 jc      error
 113                 //
 114                 // EMS is good
 115                 //
 116                 mov     emmcfems,1
 117                 jmp End
 118                 error:
 119                 //
 120                 // EMS is bad
 121                 //
 122                 mov     emmcfems,0
 123                 End:
 124         }
 125         return(emmcfems);
 126 }
 127
 128
 129 /*
 130 ======================
 131 =
 132 = MML_SetupEMS
 133 =
 134 =======================
 135 */
 136
 137 unsigned MML_SetupEMS(mminfo_t *mm)
 138 {
 139         char    str[80],str2[10];
 140         unsigned        err;
 141         boolean errorflag=false;
 142         union REGS CPURegs;
 143
 144         unsigned int EMSVer = 0;
 145         unsigned        totalEMSpages,freeEMSpages,EMSpageframe,EMSpagesmapped,EMShandle;
 146         totalEMSpages = freeEMSpages = EMSpageframe = EMSpagesmapped = 0;
 147
 148         __asm
 149                 {
 150                 mov     ah,EMS_STATUS
 151                 int     EMS_INT                                         // make sure EMS hardware is present
 152                 or      ah,ah
 153                 jnz     error
 154
 155                 mov     ah,EMS_VERSION
 156                 int     EMS_INT
 157                 or      ah,ah
 158                 jnz     error
 159                 mov     [EMSVer],ax                             //      set EMSVer
 160                 cmp     al,0x32                                         // only work on ems 3.2 or greater
 161                 jb      error
 162
 163                 mov     ah,EMS_GETFRAME
 164                 int     EMS_INT                                         // find the page frame address
 165                 or      ah,ah
 166                 jnz     error
 167                 mov     [EMSpageframe],bx
 168
 169                 mov     ah,EMS_GETPAGES
 170                 int     EMS_INT                                         // find out how much EMS is there
 171                 or      ah,ah
 172                 jnz     error
 173                 mov     [totalEMSpages],dx
 174                 mov     [freeEMSpages],bx
 175                 or      bx,bx
 176                 jz      noEMS                                           // no EMS at all to allocate
 177                                                                                         //EXPAND DONG!!!!
 178                 cmp     [EMSVer],0x40
 179                 jb      low
 180                 cmp     bx,[freeEMSpages]
 181                 jle     getpages
 182                 mov     bx,[freeEMSpages]
 183                 jmp     getpages
 184
 185 low:
 186                 cmp     bx,4
 187                 jle     getpages                                        // there is only 1,2,3,or 4 pages
 188                 mov     bx,4                                            // we can't use more than 4 pages
 189
 190 getpages:
 191                 mov     [EMSpagesmapped],bx
 192                 mov     ah,EMS_ALLOCPAGES                       // allocate up to 64k of EMS
 193                 int     EMS_INT
 194                 or      ah,ah
 195                 jnz     error
 196                 mov     [EMShandle],dx
 197                 jmp End
 198 error:
 199                 mov     errorflag,1
 200                 jmp End
 201 noEMS:
 202 End:
 203         }
 204         if(errorflag==true)
 205         {
 206                 err = CPURegs.h.ah;
 207                 strcpy(str,"MML_SetupEMS: EMS error 0x");
 208                 itoa(err,str2,16);
 209                 strcpy(str,str2);
 210                 printf("%s\n",str);
 211                 return err;
 212         }
 213         mm->totalEMSpages=totalEMSpages;
 214         mm->freeEMSpages=freeEMSpages;
 215         mm->EMSpageframe=EMSpageframe;
 216         mm->EMSpagesmapped=EMSpagesmapped;
 217         mm->EMShandle=EMShandle;
 218         mm->EMSVer=EMSVer;
 219         return 0;
 220 }
 221
 222
 223 /*
 224 ======================
 225 =
 226 = MML_ShutdownEMS
 227 =
 228 =======================
 229 */
 230
 231 void MML_ShutdownEMS(mminfo_t *mm)
 232 {
 233         boolean errorflag=false;
 234         unsigned EMShandle=mm->EMShandle;
 235
 236         if(!EMShandle)
 237                 return;
 238         __asm
 239         {
 240                 mov     ah,EMS_FREEPAGES
 241                 mov     dx,[EMShandle]
 242                 int     EMS_INT
 243                 or      ah,ah
 244                 jz      ok
 245                 mov     errorflag,1
 246                 ok:
 247         }
 248         if(errorflag==true) printf("MML_ShutdownEMS: Error freeing EMS!");      //++++ add something
 249 }
 250
 251 /*
 252 ====================
 253 =
 254 = MM_MapEMS
 255 =
 256 = Maps the 64k of EMS used by memory manager into the page frame
 257 = for general use.  This only needs to be called if you are keeping
 258 = other things in EMS.
 259 =
 260 ====================
 261 */
 262
 263 unsigned MM_MapEMS(mminfo_t *mm)
 264 {
 265         char    str[80],str2[10];
 266         unsigned        err, EMShandle;
 267         boolean errorflag=false;
 268         int     i;
 269         union REGS CPURegs;
 270         EMShandle=mm->EMShandle;
 271
 272         for (i=0;i<mm->EMSpagesmapped;i++)
 273         {
 274                 __asm
 275                 {
 276                         mov     ah,EMS_MAPPAGE
 277                         mov     bx,[i]                  // logical page
 278                         mov     al,bl                   // physical page
 279                         mov     dx,[EMShandle]  // handle
 280                         int     EMS_INT
 281                         or      ah,ah
 282                         jnz     error
 283                         jmp End
 284                         error:
 285                         mov     errorflag,1
 286                         End:
 287                 }
 288                 if(errorflag==true)
 289                 {
 290                         err = CPURegs.h.ah;
 291                         strcpy(str,"MM_MapEMS: EMS error 0x");
 292                         itoa(err,str2,16);
 293                         strcpy(str,str2);
 294                         printf("%s\n",str);
 295                         return err;
 296                 }
 297         }
 298         return 0;
 299 }
 300
 301 //==========================================================================
 302
 303 /*
 304 ======================
 305 =
 306 = MML_CheckForXMS
 307 =
 308 = Check for XMM driver
 309 =
 310 =======================
 311 */
 312
 313 boolean MML_CheckForXMS(mminfo_t *mm)
 314 {
 315         boolean errorflag=false;
 316         mm->numUMBs = 0;
 317
 318         __asm
 319         {
 320                 mov     ax,0x4300
 321                 int     0x2f                            // query status of installed diver
 322                 cmp     al,0x80
 323                 je      good
 324                 mov     errorflag,1
 325                 good:
 326         }
 327         if(errorflag==true) return false;
 328         else return true;
 329 }
 330
 331
 332 /*
 333 ======================
 334 =
 335 = MML_SetupXMS
 336 =
 337 = Try to allocate all upper memory block
 338 =
 339 =======================
 340 */
 341
 342 void MML_SetupXMS(mminfo_t *mm, mminfotype *mmi)
 343 {
 344         unsigned        base,size;
 345
 346 getmemory:
 347         __asm
 348         {
 349                 mov     ax,0x4310
 350                 int     0x2f
 351                 mov     [WORD PTR XMSaddr],bx
 352                 mov     [WORD PTR XMSaddr+2],es         // function pointer to XMS driver
 353
 354                 mov     ah,XMS_ALLOCUMB
 355                 mov     dx,0xffff                                       // try for largest block possible
 356                 //mov     ax,dx                                         // Set available Kbytes.
 357                 call    [DWORD PTR XMSaddr]
 358                 or      ax,ax
 359                 jnz     gotone
 360
 361                 cmp     bl,0xb0                                         // error: smaller UMB is available
 362                 jne     done;
 363
 364                 mov     ah,XMS_ALLOCUMB
 365                 call    [DWORD PTR XMSaddr]             // DX holds largest available UMB
 366                 or      ax,ax
 367                 jz      done                                            // another error...
 368
 369 gotone:
 370                 mov     [base],bx
 371                 mov     [size],dx
 372 done:
 373         }
 374         printf("base=%u ", base); printf("size=%u\n", size);
 375         MML_UseSpace(base,size, mm);
 376         mmi->XMSmem += size*16;
 377         mm->UMBbase[mm->numUMBs] = base;
 378         mm->numUMBs++;
 379         if(mm->numUMBs < MAXUMBS)
 380                 goto getmemory;
 381 }
 382
 383
 384 /*
 385 ======================
 386 =
 387 = MML_ShutdownXMS
 388 =
 389 ======================
 390 */
 391
 392 void MML_ShutdownXMS(mminfo_t *mm)
 393 {
 394         int     i;
 395         unsigned        base;
 396
 397         for (i=0;i<mm->numUMBs;i++)
 398         {
 399                 base = mm->UMBbase[i];
 400                 __asm
 401                 {
 402                         mov     ah,XMS_FREEUMB
 403                         mov     dx,[base]
 404                         call    [DWORD PTR XMSaddr]
 405                 }
 406         }
 407 }
 408
 409 //==========================================================================
 410
 411 /*
 412 ======================
 413 =
 414 = MML_UseSpace
 415 =
 416 = Marks a range of paragraphs as usable by the memory manager
 417 = This is used to mark space for the near heap, far heap, ems page frame,
 418 = and upper memory blocks
 419 =
 420 ======================
 421 */
 422
 423 void MML_UseSpace(/*d*/word segstart, dword seglength, mminfo_t *mm)
 424 {
 425         mmblocktype huge *scan,huge *last;
 426         dword   oldend;
 427         dword           extra;
 428
 429         scan = last = mm->mmhead;
 430         mm->mmrover = mm->mmhead;               // reset rover to start of memory
 431         scan->segm=1;
 432
 433 //
 434 // search for the block that contains the range of segments
 435 //
 436         while(scan->start+scan->length < segstart)
 437         {
 438                 last = scan;
 439                 scan = scan->next;
 440         }
 441
 442         //find out how many blocks it span!
 443         if(seglength>0xfffflu)
 444         {
 445                 scan->segm=seglength/0xfffflu;
 446         }
 447
 448 //
 449 // take the given range out of the block
 450 //
 451         oldend = scan->start + scan->length;
 452         extra = oldend - (segstart+seglength);
 453         //++++emsver stuff!
 454         if(extra>0xfffflu)
 455         {
 456                 /*__asm
 457                 {
 458                         push    ds
 459                         mov     ax,ds
 460                         inc             ax
 461                         mov     ds,ax
 462                 }*/
 463 printf("segm=%u ", scan->segm);
 464 printf("ex=%lu  ", extra);
 465 printf("len=%u  ", scan->length);
 466 printf("segsta=%u       ", segstart);
 467 printf("seglen=%lu\n", seglength);
 468
 469 //MML_UseSpace(?segstart?, ?length?, mm);
 470
 471                 /*__asm
 472                 {
 473                         pop ds
 474                 }*/
 475                 //printf("MML_UseSpace: Segment spans two blocks!\n");
 476         }
 477
 478 //segu:
 479 //++++todo: linked list of segment!
 480 //printf("segm=%lu\n", segm);
 481         if(segstart == scan->start)
 482         {
 483                 last->next = scan->next;                        // unlink block
 484                 MM_FreeBlock(scan, mm);
 485                 scan = last;
 486         }
 487         else
 488                 scan->length = segstart-scan->start;    // shorten block
 489
 490 //      segm--;
 491
 492         if(extra > 0)
 493         {
 494                 MM_GetNewBlock(mm);
 495                 mm->mmnew->next = scan->next;
 496                 scan->next = mm->mmnew;
 497                 mm->mmnew->start = segstart+seglength;
 498                 mm->mmnew->length = extra;
 499                 mm->mmnew->attributes = LOCKBIT;
 500         }//else if(segm>0) goto segu;
 501
 502 }
 503
 504 //==========================================================================
 505
 506 /*
 507 ====================
 508 =
 509 = MML_ClearBlock
 510 =
 511 = We are out of blocks, so free a purgable block
 512 =
 513 ====================
 514 */
 515
 516 void MML_ClearBlock(mminfo_t *mm)
 517 {
 518         mmblocktype huge *scan,huge *last;
 519
 520         scan = mm->mmhead->next;
 521
 522         while(scan)
 523         {
 524                 if(!(scan->attributes&LOCKBIT) && (scan->attributes&PURGEBITS))
 525                 {
 526                         MM_FreePtr(scan->useptr, mm);
 527                         return;
 528                 }
 529                 scan = scan->next;
 530         }
 531
 532         printf("MM_ClearBlock: No purgable blocks!\n");
 533 }
 534
 535
 536 //==========================================================================
 537
 538 /*
 539 ===================
 540 =
 541 = MM_Startup
 542 =
 543 = Grabs all space from turbo with malloc/farmalloc
 544 = Allocates bufferseg misc buffer
 545 =
 546 ===================
 547 */
 548
 549 void MM_Startup(mminfo_t *mm, mminfotype *mmi)
 550 {
 551         int i;
 552         dword length;//,farlen;
 553         void huge       *start;
 554         unsigned        segstart,seglength,endfree;
 555
 556         if(mm->mmstarted)
 557                 MM_Shutdown(mm);
 558
 559         mm->mmstarted = true;
 560         mm->bombonerror = true;
 561 //
 562 // set up the linked list (everything in the free list;
 563 //
 564         mm->mmhead = NULL;
 565         mm->mmfree = &(mm->mmblocks[0]);
 566         for(i=0;i<MAXBLOCKS-1;i++)
 567         {
 568                 mm->mmblocks[i].next = &(mm->mmblocks[i+1]);
 569         }
 570         mm->mmblocks[i].next = NULL;
 571
 572 //
 573 // locked block of all memory until we punch out free space
 574 //
 575         MM_GetNewBlock(mm);
 576         mm->mmhead = mm->mmnew;                         // this will allways be the first node
 577         mm->mmnew->start = 0;
 578         mm->mmnew->length = 0xffff;                     //todo: mm make it fucking massive as fuck!~
 579         mm->mmnew->attributes = LOCKBIT;
 580         mm->mmnew->next = NULL;
 581         mm->mmrover = mm->mmhead;
 582
 583 //      farlen=_bios_memsize()*1024;
 584
 585 //
 586 // get all available near conventional memory segments
 587 //
 588 //----  length=coreleft();
 589         _nheapgrow();
 590         length=_memavl();
 591         start = (void huge *)(mm->nearheap = malloc(length));
 592
 593         length -= 16-(FP_OFF(start)&15);
 594         length -= SAVENEARHEAP;
 595         seglength = length / 16;                        // now in paragraphs
 596         segstart = FP_SEG(start)+(FP_OFF(start)+15)/16;
 597         MML_UseSpace(segstart,seglength, mm);
 598         mmi->nearheap = length;
 599
 600 //
 601 // get all available far conventional memory segments
 602 //
 603 //----  length=farcoreleft();
 604         _fheapgrow();
 605         length=_memavl();
 606         //length-=farlen;
 607         start = mm->farheap = halloc(length, sizeof(dword));
 608         //start = mm->farheap = _fmalloc(length);
 609         length -= 16-(FP_OFF(start)&15);
 610         length -= SAVEFARHEAP;
 611         seglength = length / 16;                        // now in paragraphs
 612         segstart = FP_SEG(start)+(FP_OFF(start)+15)/16;
 613         MML_UseSpace(segstart,seglength, mm);
 614         mmi->farheap = length;
 615         mmi->mainmem = mmi->nearheap + mmi->farheap;
 616
 617
 618 //
 619 // detect EMS and allocate up to 64K at page frame
 620 //
 621         printf("EMS!\n\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!
 622         mmi->EMSmem = 0;
 623         for(i = 1;i < __argc;i++)
 624         {
 625                 if(US_CheckParm(__argv[i],ParmStringsexmm) == 0)
 626                         goto emsskip;                           // param NOEMS
 627         }
 628         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!
 629         if(MML_CheckForEMS())
 630         {
 631 //printf("EMS1\n");
 632                 MML_SetupEMS(mm);                                       // allocate space
 633                 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!
 634                 //TODO: EMS4! AND EMS 3.2 MASSIVE DATA HANDLMENT!
 635                 MML_UseSpace(mm->EMSpageframe,(mm->EMSpagesmapped)*0x4000lu, mm);
 636 //printf("EMS3\n");
 637                 MM_MapEMS(mm);                                  // map in used pages
 638 //printf("EMS4\n");
 639                 mmi->EMSmem = (mm->EMSpagesmapped)*0x4000lu;
 640         }
 641
 642 //
 643 // detect XMS and get upper memory blocks
 644 //
 645 emsskip:
 646         mmi->XMSmem = 0;
 647         for(i = 1;i < __argc;i++)
 648         {
 649                 if(US_CheckParm(__argv[i],ParmStringsexmm) == 0)
 650                         goto xmsskip;                           // param NOXMS
 651         }
 652         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!
 653         if(MML_CheckForXMS(mm))
 654         {
 655                 printf("XMS!\n");
 656                 MML_SetupXMS(mm, mmi);                                  // allocate as many UMBs as possible
 657         }
 658
 659 //
 660 // allocate the misc buffer
 661 //
 662 xmsskip:
 663         mm->mmrover = mm->mmhead;               // start looking for space after low block
 664
 665         MM_GetPtr(&(mm->bufferseg),BUFFERSIZE, mm, mmi);
 666 }
 667
 668 //==========================================================================
 669
 670 /*
 671 ====================
 672 =
 673 = MM_Shutdown
 674 =
 675 = Frees all conventional, EMS, and XMS allocated
 676 =
 677 ====================
 678 */
 679
 680 void MM_Shutdown(mminfo_t *mm)
 681 {
 682         if(!(mm->mmstarted))
 683                 return;
 684
 685         _ffree(mm->farheap);
 686         printf("far freed\n");
 687         free(mm->nearheap);
 688         printf("near freed\n");
 689         //hfree(mm->hugeheap);
 690         //printf("huge freed\n");
 691         if(MML_CheckForEMS()){ MML_ShutdownEMS(mm); printf("EMS freed\n"); }
 692         if(MML_CheckForXMS(mm)){ MML_ShutdownXMS(mm); printf("XMS freed\n"); }
 693 }
 694
 695 //==========================================================================
 696
 697 /*
 698 ====================
 699 =
 700 = MM_GetPtr
 701 =
 702 = Allocates an unlocked, unpurgable block
 703 =
 704 ====================
 705 */
 706
 707 void MM_GetPtr(memptr *baseptr,dword size, mminfo_t *mm, mminfotype *mmi)
 708 {
 709         mmblocktype huge *scan,huge *lastscan,huge *endscan,huge *purge,huge *next;
 710         int                     search;
 711         unsigned        needed,startseg;
 712
 713         needed = (size+15)/16;          // convert size from bytes to paragraphs
 714
 715         MM_GetNewBlock(mm);                             // fill in start and next after a spot is found
 716         mm->mmnew->length = needed;
 717         mm->mmnew->useptr = baseptr;
 718         mm->mmnew->attributes = BASEATTRIBUTES;
 719
 720         for(search = 0; search<3; search++)
 721         {
 722         //
 723         // first search:        try to allocate right after the rover, then on up
 724         // second search:       search from the head pointer up to the rover
 725         // third search:        compress memory, then scan from start
 726                 if(search == 1 && mm->mmrover == mm->mmhead)
 727                         search++;
 728
 729                 switch(search)
 730                 {
 731                 case 0:
 732                         lastscan = mm->mmrover;
 733                         scan = mm->mmrover->next;
 734                         endscan = NULL;
 735                         break;
 736                 case 1:
 737                         lastscan = mm->mmhead;
 738                         scan = mm->mmhead->next;
 739                         endscan = mm->mmrover;
 740                         break;
 741                 case 2:
 742                         MM_SortMem(mm);
 743                         lastscan = mm->mmhead;
 744                         scan = mm->mmhead->next;
 745                         endscan = NULL;
 746                         break;
 747                 }
 748
 749                 startseg = lastscan->start + lastscan->length;
 750
 751                 while(scan != endscan)
 752                 {
 753                         if(scan->start - startseg >= needed)
 754                         {
 755                         //
 756                         // got enough space between the end of lastscan and
 757                         // the start of scan, so throw out anything in the middle
 758                         // and allocate the new block
 759                         //
 760                                 purge = lastscan->next;
 761                                 lastscan->next = mm->mmnew;
 762                                 mm->mmnew->start = *(unsigned *)baseptr = startseg;
 763                                 mm->mmnew->next = scan;
 764                                 while(purge != scan)
 765                                 {       // free the purgable block
 766                                         next = purge->next;
 767                                         MM_FreeBlock(purge, mm);
 768                                         purge = next;           // purge another if not at scan
 769                                 }
 770                                 mm->mmrover = mm->mmnew;
 771                                 return; // good allocation!
 772                         }
 773
 774                         //
 775                         // if this block is purge level zero or locked, skip past it
 776                         //
 777                         if((scan->attributes & LOCKBIT)
 778                                 || !(scan->attributes & PURGEBITS) )
 779                         {
 780                                 lastscan = scan;
 781                                 startseg = lastscan->start + lastscan->length;
 782                         }
 783
 784
 785                         scan=scan->next;                // look at next line
 786                 }
 787         }
 788
 789         if (mm->bombonerror)
 790                 printf(OUT_OF_MEM_MSG,(size-mmi->nearheap));
 791         else
 792                 mm->mmerror = true;
 793 }
 794
 795 //==========================================================================
 796
 797 /*
 798 ====================
 799 =
 800 = MM_FreePtr
 801 =
 802 = Allocates an unlocked, unpurgable block
 803 =
 804 ====================
 805 */
 806
 807 void MM_FreePtr(memptr *baseptr, mminfo_t *mm)
 808 {
 809         mmblocktype huge *scan,huge *last;
 810
 811         last = mm->mmhead;
 812         scan = last->next;
 813
 814         if(baseptr == mm->mmrover->useptr)      // removed the last allocated block
 815                 mm->mmrover = mm->mmhead;
 816
 817         while(scan->useptr != baseptr && scan)
 818         {
 819                 last = scan;
 820                 scan = scan->next;
 821         }
 822
 823         if(!scan)
 824         {
 825                 printf("MM_FreePtr: Block not found!");
 826                 return;
 827         }
 828
 829         last->next = scan->next;
 830
 831         MM_FreeBlock(scan, mm);
 832 }
 833 //==========================================================================
 834
 835 /*
 836 =====================
 837 =
 838 = MM_SetPurge
 839 =
 840 = Sets the purge level for a block (locked blocks cannot be made purgable)
 841 =
 842 =====================
 843 */
 844
 845 void MM_SetPurge(memptr *baseptr, int purge, mminfo_t *mm)
 846 {
 847         mmblocktype huge *start;
 848
 849         start = mm->mmrover;
 850
 851         do
 852         {
 853                 if(mm->mmrover->useptr == baseptr)
 854                         break;
 855
 856                 mm->mmrover = mm->mmrover->next;
 857
 858                 if(!mm->mmrover)
 859                         mm->mmrover = mm->mmhead;
 860                 else if(mm->mmrover == start)
 861                 {
 862                         printf("MM_SetPurge: Block not found!");
 863                         return;
 864                 }
 865
 866         } while(1);
 867
 868         mm->mmrover->attributes &= ~PURGEBITS;
 869         mm->mmrover->attributes |= purge;
 870 }
 871
 872 //==========================================================================
 873
 874 /*
 875 =====================
 876 =
 877 = MM_SetLock
 878 =
 879 = Locks / unlocks the block
 880 =
 881 =====================
 882 */
 883
 884 void MM_SetLock(memptr *baseptr, boolean locked, mminfo_t *mm)
 885 {
 886         mmblocktype huge *start;
 887
 888         start = mm->mmrover;
 889
 890         do
 891         {
 892                 if(mm->mmrover->useptr == baseptr)
 893                         break;
 894
 895                 mm->mmrover = mm->mmrover->next;
 896
 897                 if(!mm->mmrover)
 898                         mm->mmrover = mm->mmhead;
 899                 else if(mm->mmrover == start)
 900                 {
 901                         printf("MM_SetLock: Block not found!");
 902                         return;
 903                 }
 904
 905         } while(1);
 906
 907         mm->mmrover->attributes &= ~LOCKBIT;
 908         mm->mmrover->attributes |= locked*LOCKBIT;
 909 }
 910
 911 //==========================================================================
 912
 913 /*
 914 =====================
 915 =
 916 = MM_SortMem
 917 =
 918 = Throws out all purgable stuff and compresses movable blocks
 919 =
 920 =====================
 921 */
 922
 923 void MM_SortMem(mminfo_t *mm)
 924 {
 925         mmblocktype huge *scan,huge *last,huge *next;
 926         unsigned        start,length,source,dest,oldborder;
 927         int                     playing;
 928
 929         //
 930         // lock down a currently playing sound
 931         //
 932 /*++++  playing = SD_SoundPlaying ();
 933         if(playing)
 934         {
 935                 switch (SoundMode)
 936                 {
 937                 case sdm_PC:
 938                         playing += STARTPCSOUNDS;
 939                         break;
 940                 case sdm_AdLib:
 941                         playing += STARTADLIBSOUNDS;
 942                         break;
 943                 }
 944                 MM_SetLock(&(memptr)audiosegs[playing],true);
 945         }
 946
 947
 948         SD_StopSound();*/
 949 //      oldborder = bordercolor;
 950 //      VW_ColorBorder (15);
 951
 952         if(beforesort)
 953                 beforesort();
 954
 955         scan = mm->mmhead;
 956
 957         last = NULL;            // shut up compiler warning
 958
 959         while(scan)
 960         {
 961                 if(scan->attributes & LOCKBIT)
 962                 {
 963                 //
 964                 // block is locked, so try to pile later blocks right after it
 965                 //
 966                         start = scan->start + scan->length;
 967                 }
 968                 else
 969                 {
 970                         if(scan->attributes & PURGEBITS)
 971                         {
 972                         //
 973                         // throw out the purgable block
 974                         //
 975                                 next = scan->next;
 976                                 MM_FreeBlock(scan, mm);
 977                                 last->next = next;
 978                                 scan = next;
 979                                 continue;
 980                         }
 981                         else
 982                         {
 983                         //
 984                         // push the non purgable block on top of the last moved block
 985                         //
 986                                 if(scan->start != start)
 987                                 {
 988                                         length = scan->length;
 989                                         source = scan->start;
 990                                         dest = start;
 991                                         while(length > 0xf00)
 992                                         {
 993                                                 movedata(source,0,dest,0,0xf00*16);
 994                                                 length -= 0xf00;
 995                                                 source += 0xf00;
 996                                                 dest += 0xf00;
 997                                         }
 998                                         movedata(source,0,dest,0,length*16);
 999
1000                                         scan->start = start;
1001                                         *(unsigned *)scan->useptr = start;
1002                                 }
1003                                 start = scan->start + scan->length;
1004                         }
1005                 }
1006
1007                 last = scan;
1008                 scan = scan->next;              // go to next block
1009         }
1010
1011         mm->mmrover = mm->mmhead;
1012
1013         if(aftersort)
1014                 aftersort();
1015
1016 //      VW_ColorBorder (oldborder);
1017
1018 /*++++  if(playing)
1019                 MM_SetLock(&(memptr)audiosegs[playing],false);*/
1020 }
1021
1022
1023 //==========================================================================
1024
1025 //****#if 0
1026 /*
1027 =====================
1028 =
1029 = MM_ShowMemory
1030 =
1031 =====================
1032 */
1033
1034 void MM_ShowMemory(mminfo_t *mm)
1035 {
1036         mmblocktype huge *scan;
1037         unsigned color,temp;//, i;
1038         long    end,owner;
1039         char    scratch[160],str[16];
1040
1041 //****  VW_SetDefaultColors();
1042 //****  VW_SetLineWidth(40);
1043 //++++mh        temp = bufferofs;
1044 //++++mh        bufferofs = 0;
1045 //****  VW_SetScreen (0,0);
1046
1047         scan = mm->mmhead;
1048
1049         end = -1;
1050
1051 //CA_OpenDebug ();
1052
1053         while(scan)
1054         {
1055                 if(scan->attributes & PURGEBITS)
1056                         color = 5;              // dark purple = purgable
1057                 else
1058                         color = 9;              // medium blue = non purgable
1059                 if(scan->attributes & LOCKBIT)
1060                         color = 12;             // red = locked
1061                 if(scan->start<=end)
1062                 {
1063                         printf("\nMM_ShowMemory: Memory block order currupted!\n");
1064                         return;
1065                 }
1066                 end = scan->start+scan->length-1;
1067 //++++          VW_Hlin(scan->start,(unsigned)end,0,color);
1068 //++++          VW_Plot(scan->start,0,15);
1069                 if(scan->next->start > end+1)
1070 //++++                  VW_Hlin(end+1,scan->next->start,0,0);   // black = free
1071
1072 //****#if 0
1073 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!
1074 strcpy(scratch,"Location:");
1075 ultoa (scan->start,str,16);
1076 strcat (scratch,str);
1077 strcat (scratch,"\tSize:");
1078 ltoa ((dword)scan->length*16,str,10);
1079 strcat (scratch,str);
1080 strcat (scratch,"\tOwner:0x");
1081 owner = (unsigned)scan->useptr;
1082 ultoa (owner,str,16);
1083 strcat (scratch,str);
1084 strcat (scratch,"\n");
1085 //++++write (debughandle,scratch,strlen(scratch));
1086 fprintf(stdout, "%s", scratch);
1087 //****#endif
1088
1089                 scan = scan->next;
1090         }
1091
1092 //CA_CloseDebug ();
1093
1094 //++++mh        IN_Ack();
1095 //****  VW_SetLineWidth(64);
1096 //++++mh        bufferofs = temp;
1097 }
1098 //****#endif
1099
1100 //==========================================================================
1101
1102
1103 /*
1104 ======================
1105 =
1106 = MM_UnusedMemory
1107 =
1108 = Returns the total free space without purging
1109 =
1110 ======================
1111 */
1112
1113 dword MM_UnusedMemory(mminfo_t *mm)
1114 {
1115         dword free;
1116         mmblocktype huge *scan;
1117
1118         free = 0;
1119         scan = mm->mmhead;
1120
1121         while(scan->next)
1122         {
1123                 free += scan->next->start - (scan->start + scan->length);
1124                 scan = scan->next;
1125         }
1126
1127         return free*16l;
1128 //      return free;
1129 }
1130
1131 //==========================================================================
1132
1133
1134 /*
1135 ======================
1136 =
1137 = MM_TotalFree
1138 =
1139 = Returns the total free space with purging
1140 =
1141 ======================
1142 */
1143
1144 dword MM_TotalFree(mminfo_t *mm)
1145 {
1146         dword free;
1147         mmblocktype huge *scan;
1148
1149         free = 0;
1150         scan = mm->mmhead;
1151
1152         while(scan->next)
1153         {
1154                 if((scan->attributes&PURGEBITS) && !(scan->attributes&LOCKBIT))
1155                         free += scan->length;
1156                 free += scan->next->start - (scan->start + scan->length);
1157                 scan = scan->next;
1158         }
1159
1160         return free*16l;
1161 //      return free;
1162 }
1163
1164 //==========================================================================
1165
1166 /*
1167 =====================
1168 =
1169 = MM_Report
1170 =
1171 =====================
1172 */
1173
1174 void MM_Report(mminfo_t *mm, mminfotype *mmi)
1175 {
1176         if(MML_CheckForEMS())
1177         {
1178                 printf("EMM %x available\n", mm->EMSVer);
1179                 printf("totalEMSpages=%u\n", mm->totalEMSpages);
1180                 printf("freeEMSpages=%u\n", mm->freeEMSpages);
1181                 printf("EMSpageframe=%x\n", mm->EMSpageframe);
1182         }
1183         if(MML_CheckForXMS(mm)) printf("XMSaddr=%Fp\n", *XMSaddr);
1184         printf("near=%lu\n", mmi->nearheap);
1185         printf("far=%lu\n", mmi->farheap);
1186         printf("EMSmem=%lu\n", mmi->EMSmem);
1187         printf("XMSmem=%lu\n", mmi->XMSmem);
1188         printf("mainmem=%lu\n", mmi->mainmem);
1189         printf("UnusedMemory=%lu\n", MM_UnusedMemory(mm));
1190         printf("TotalFree=%lu\n", MM_TotalFree(mm));
1191 //      printf("\n");
1192 //      printf("UnusedMemory=%lu kb\n", MM_UnusedMemory()/10248);
1193 //      printf("TotalFree=%lu kb\n", MM_TotalFree()/10248);
1194 }
1195
1196 //==========================================================================
1197
1198 /*
1199 =====================
1200 =
1201 = MM_EMSVer
1202 =
1203 =====================
1204
1205
1206 int MM_EMSVer(void)
1207 {
1208         int EMSver;
1209         __asm
1210         {
1211                 mov             ah,EMS_VERSION
1212                 int             EMS_INT
1213                 mov             EMSver,ax
1214         }
1215         return(EMSver);
1216 }*/
1217
1218 //==========================================================================
1219
1220 /*
1221 =====================
1222 =
1223 = MM_BombOnError
1224 =
1225 =====================
1226 */
1227
1228 void MM_BombOnError(boolean bomb, mminfo_t *mm)
1229 {
1230         mm->bombonerror = bomb;
1231 }
1232
1233 void MM_GetNewBlock(mminfo_t *mm)
1234 {
1235         if(!mm->mmfree)
1236                 MML_ClearBlock(mm);
1237         mm->mmnew=mm->mmfree;
1238         mm->mmfree=mm->mmfree->next;
1239         /*if(!(mm->mmnew=mm->mmfree))
1240         {
1241                 printf("MM_GETNEWBLOCK: No free blocks!");
1242                 return;
1243         }
1244         mm->mmfree=mm->mmfree->next;*/
1245 }
1246
1247 void MM_FreeBlock(mmblocktype *x, mminfo_t *mm)
1248 {
1249         x->useptr=NULL;
1250         x->next=mm->mmfree;
1251         mm->mmfree=x;
1252 }
1253
1254 void MM_seguin(void)
1255 {
1256         __asm
1257         {
1258                 push    ds
1259                 mov     ax,ds
1260                 inc             ax
1261                 mov     ds,ax
1262         }
1263 }
1264
1265 void MM_segude(void)
1266 {
1267         __asm
1268         {
1269                 pop ds
1270         }
1271 }
1272
1273 /*
1274 pull data from far and put it into ds var
1275 mov ax,es:si
1276 mov x,ax
1277 */
1278 /*
1279 ss stack segment
1280 sp top of stack
1281 bp bottem of stack
1282 */