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C/C++ Source or Header  |  1993-09-24  |  16KB  |  495 lines
  1. /*
  2. ***************************************************************************
  3. *
  4. * Datei:
  5. *      RSysCRC.c
  6. *
  7. * Inhalt:
  8. *
  9. *      --- Globale Routinen ---
  10. *
  11. *    int OpenCRCWindow ( void );
  12. *    void CRCSum ( void );
  13. *
  14. *      --- Lokale  Routinen ---
  15. *
  16. *    static ULONG bCalcCRC16 ( UBYTE *msg , long size );
  17. *    static ULONG bCalcCRC32 ( UBYTE *s , long len );
  18. *
  19. * Bemerkungen:
  20. *      CRC-Berechnungs-Routinen.
  21. *
  22. * Erstellungsdatum:
  23. *      07-Jan-93     Rolf Böhme
  24. *
  25. * Änderungen:
  26. *      07-Jan-93     Rolf Böhme      Erstellung
  27. *
  28. ***************************************************************************
  29. */
  30.  
  31. #include "RSys.h"
  32.  
  33.     /*
  34.      * Die Tabelle, die die Polynomwerte zur Berechnung
  35.      * des CRC-16-Algorithmus beinhaltet.
  36.      */
  37. static
  38. WORD    crctab[CRCTABSIZE] =
  39. {
  40.     0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
  41.     0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
  42.     0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
  43.     0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
  44.     0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
  45.     0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
  46.     0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
  47.     0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
  48.     0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
  49.     0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
  50.     0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
  51.     0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
  52.     0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
  53.     0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
  54.     0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
  55.     0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
  56.     0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
  57.     0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
  58.     0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
  59.     0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
  60.     0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
  61.     0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
  62.     0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
  63.     0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
  64.     0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
  65.     0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
  66.     0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
  67.     0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
  68.     0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
  69.     0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
  70.     0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
  71.     0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0,
  72. };
  73.  
  74.     /*
  75.      * bCalcCRC16() berechnet die CRC-16-Checksumme eines
  76.      * beliebigen Datenblocks der Länge size , auf den
  77.      * msg zeigt.
  78.      */
  79. static ULONG
  80. bCalcCRC16(UBYTE * msg, long size)
  81. {
  82.     WORD    crc;
  83.  
  84.     for (crc = 0; size--; msg++) crc = (crc << 8) ^ crctab[(crc >> 8) ^ *msg];
  85.  
  86.     return (ULONG) crc;
  87. }
  88.  
  89.     /*
  90.      * Die Tabelle, die die Polynomwerte zur Berechnung
  91.      * des CRC-32-Algorithmus beinhaltet.
  92.      */
  93. unsigned long crc_32_tab[CRCTABSIZE] =
  94. {
  95.     0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
  96.     0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
  97.     0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
  98.     0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
  99.     0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
  100.     0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
  101.     0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
  102.     0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
  103.     0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
  104.     0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
  105.     0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
  106.     0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
  107.     0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
  108.     0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
  109.     0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
  110.     0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
  111.     0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
  112.     0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
  113.     0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
  114.     0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
  115.     0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
  116.     0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
  117.     0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
  118.     0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
  119.     0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
  120.     0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
  121.     0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
  122.     0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
  123.     0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
  124.     0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
  125.     0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
  126.     0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
  127.     0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
  128.     0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
  129.     0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
  130.     0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
  131.     0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
  132.     0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
  133.     0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
  134.     0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
  135.     0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
  136.     0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
  137.     0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
  138.     0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
  139.     0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
  140.     0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
  141.     0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
  142.     0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
  143.     0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
  144.     0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
  145.     0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
  146.     0x2d02ef8dL
  147. };
  148.  
  149.     /*
  150.      * bCalcCRC32() berechnet die CRC-32-Checksumme eines
  151.      * beliebigen Datenblocks der Länge len , auf den
  152.      * s zeigt.
  153.      */
  154. static ULONG
  155. bCalcCRC32(UBYTE * s, long len)
  156. {
  157.     register unsigned long crcval;
  158.     ULONG crc32val;
  159.  
  160.     crcval = crc32val;
  161.     while (len--) crcval = crc_32_tab[(UBYTE) crcval ^ (UBYTE) (*s++)] ^ (crcval >> 8);
  162.     crc32val = crcval;
  163.  
  164.     return crc32val;
  165. }
  166.  
  167.     /*
  168.      * Die Datenstrukturen für das CRC-Steuer-Window
  169.      * werden hier vereinbart und initialisiert.
  170.      */
  171. static struct Window *CRCWnd = NULL;
  172. static struct Gadget *CRCGList = NULL;
  173. static struct Gadget *CRCGadgets[CRC_CNT];
  174. static UWORD CRCLeft = 178;
  175. static UWORD CRCTop = 55;
  176. static UWORD CRCWidth = 244;
  177. static UWORD CRCHeight = 52;
  178. static UBYTE *CRCWdt = (UBYTE *) NAME " " VERSION " - Compute CRC";
  179.  
  180. static UBYTE *TypeCYGad0Labels[]=
  181. {
  182.     (UBYTE *) "CRC 16",
  183.     (UBYTE *) "CRC 32",
  184.     NULL};
  185.  
  186. static UWORD CRCGTypes[]=
  187. {
  188.     TEXT_KIND,
  189.     CYCLE_KIND,
  190.     BUTTON_KIND,
  191.     TEXT_KIND,
  192.     BUTTON_KIND
  193. };
  194.  
  195. static struct NewGadget CRCNGad[]=
  196. {
  197.     51, 3, 186, 13, (UBYTE *) "File", NULL, GD_FileTGad, PLACETEXT_LEFT, NULL, NULL,
  198.     51, 19, 93, 13, (UBYTE *) "Type", NULL, GD_TypeCRCCYGad, PLACETEXT_LEFT, NULL, NULL,
  199.     149, 19, 88, 13, (UBYTE *) "Select", NULL, GD_SelectFileGad, PLACETEXT_IN, NULL, NULL,
  200.     51, 35, 93, 13, (UBYTE *) "CRC", NULL, GD_CRCTGad, PLACETEXT_LEFT, NULL, NULL,
  201.     149, 35, 88, 13, (UBYTE *) "Compute", NULL, GD_ComputeGad, PLACETEXT_IN, NULL, NULL
  202. };
  203.  
  204. static ULONG *CRCGTags[]=
  205. {
  206.     (ULONG *) (GTTX_Text), (ULONG *) "-", (ULONG *) (GTTX_Border), (ULONG *) TRUE, (ULONG *) (TAG_DONE),
  207.     (ULONG *) (GTCY_Labels), (ULONG *) & TypeCYGad0Labels[0], (ULONG *) (TAG_DONE),
  208.     (ULONG *) (TAG_DONE),
  209.     (ULONG *) (GTTX_Text), (ULONG *) "-", (ULONG *) (GTTX_Border), (ULONG *) TRUE, (ULONG *) (TAG_DONE),
  210.     (ULONG *) (TAG_DONE)
  211. };
  212.  
  213.     /*
  214.      * OpenCRCWindow() öffnet das CRC-Kontrollfenster und
  215.      * gibt eine evtl. Fehlernummer zurück.
  216.      */
  217. int
  218. OpenCRCWindow(void)
  219. {
  220.     struct NewGadget ng;
  221.     struct Gadget *g;
  222.     UWORD lc,
  223.             tc;
  224.     UWORD wleft = CRCLeft,
  225.             wtop = CRCTop,
  226.             ww,
  227.             wh;
  228.     int    gl[] = { GD_FileTGad - GD_FileTGad, GD_CRCTGad - GD_FileTGad};
  229.  
  230.     DPOS;
  231.  
  232.    AdjustWindowDimensions(Scr, CRCLeft, CRCTop, CRCWidth, CRCHeight,
  233.                                &wleft, &wtop, &ww, &wh);
  234.  
  235.     if (!(g = CreateContext(&CRCGList))) return 1L;
  236.  
  237.     for (lc = 0, tc = 0; lc < CRC_CNT; lc++)
  238.     {
  239.         CopyMem((char *)&CRCNGad[lc], (char *)&ng, (long)sizeof(struct NewGadget));
  240.  
  241.         ng.ng_VisualInfo = VisualInfo;
  242.         ng.ng_TextAttr = Font;
  243.         ng.ng_LeftEdge = OffX + ComputeX(ng.ng_LeftEdge);
  244.         ng.ng_TopEdge = OffY + ComputeY(ng.ng_TopEdge);
  245.         ng.ng_Width = ComputeX(ng.ng_Width);
  246.         ng.ng_Height = ComputeY(ng.ng_Height);
  247.  
  248.         CRCGadgets[lc] = g = CreateGadgetA((ULONG) CRCGTypes[lc], g, &ng, (struct TagItem *) & CRCGTags[tc]);
  249.  
  250.         makelabelvisible(CRCGadgets[lc]);
  251.  
  252.         while (CRCGTags[tc])    tc += 2;
  253.  
  254.         tc++;
  255.  
  256.         if (NOT g) return 2L;
  257.     }
  258.  
  259.         /*
  260.          * Das Fenster wird geöffnet.
  261.          */
  262.     if (NOT(CRCWnd = OpenWindowTags(NULL,
  263.                                               WA_Left, wleft,
  264.                                               WA_Top, wtop,
  265.                                               WA_Width, ww,
  266.                                               WA_Height, wh,
  267.                                               WA_IDCMP, TEXTIDCMP |
  268.                                               CYCLEIDCMP |
  269.                                               BUTTONIDCMP |
  270.                                               IDCMP_CLOSEWINDOW |
  271.                                               IDCMP_VANILLAKEY |
  272.                                               IDCMP_REFRESHWINDOW,
  273.                                               WA_Flags, WFLG_DRAGBAR |
  274.                                               WFLG_DEPTHGADGET |
  275.                                               WFLG_CLOSEGADGET |
  276.                                               WFLG_SMART_REFRESH |
  277.                                               WFLG_ACTIVATE |
  278.                                               WFLG_RMBTRAP,
  279.                                               WA_Title, CRCWdt,
  280.                                               WA_PubScreenFallBack, TRUE,
  281.                                               WA_PubScreen, Scr,
  282.                                               TAG_DONE)))
  283.         return 4L;
  284.  
  285.     RefreshRastPort(CRCWnd,CRCGadgets,gl, 2, FALSE, CRCGList);
  286.  
  287.     return NULL;
  288. }
  289.  
  290.     /*
  291.      * CRCSumm verwaltet die Messages vom CRC-Window und
  292.      * ruft die CRC-Routinen auf.
  293.      */
  294. void
  295. CRCSum(void)
  296. {
  297.     struct IntuiMessage *message;
  298.     ULONG class,
  299.             code;
  300.     APTR    object;
  301.     char    name[MAXFULLNAME],
  302.             shortname[40];
  303.     int    id,
  304.             CRCtype = CRC16;
  305.     ULONG size,
  306.             sum,
  307.             (*CRCfunc[2]) (UBYTE * s, long len)=
  308.     {
  309.         bCalcCRC16, bCalcCRC32
  310.     };
  311.     UBYTE *filebuff;
  312.     BPTR    file;
  313.     char    help[10];
  314.  
  315.     DPOS;
  316.  
  317.    HandleHelp(MN_CRCSum);
  318.  
  319.     Flags.quit_crc = 0;
  320.  
  321.     name[0] = STRINGEND;
  322.     shortname[0] = STRINGEND;
  323.  
  324.         /*
  325.          * Das Fenster wird mit der Standard-Schnittestelle
  326.          * OpenASysWindow() geöffnet, die auch die
  327.          * Fehlerbehandlung übernimmt.
  328.          */
  329.     if (OpenASysWindow(OpenCRCWindow, NO_KILL))
  330.     {
  331.             /*
  332.              * Falls das Hauptfenster geööfnet ist, wird eine
  333.              * Info im Message-Feld eingeblendet und das
  334.              * Hauptfenster gegen Eingaben gesperrt.
  335.              */
  336.         PrintInfo("Computing CRC", SPEAK, 0);
  337.  
  338.       LockMainWindow(LOCK);
  339.  
  340.             /*
  341.              * Wie üblich werden in dieser Schleife alle
  342.              * Nachrichten bearbeitet, die beim CRC-Window
  343.              * eintreffen.
  344.              */
  345.         do
  346.         {
  347.             Wait(1L << CRCWnd->UserPort->mp_SigBit);
  348.  
  349.             while ((message = (struct IntuiMessage *)GT_GetIMsg(CRCWnd->UserPort)) != NULL)
  350.             {
  351.                 class = message->Class;
  352.                 code = message->Code;
  353.                 object = message->IAddress;
  354.  
  355.                 GT_ReplyIMsg(message);
  356.  
  357.                 switch (class)
  358.                 {
  359.                         /*
  360.                          * Das Closegadget wurde angeklickt. Das
  361.                          * Unterprogramm wird damit beendet.
  362.                          */
  363.                     case IDCMP_CLOSEWINDOW:
  364.                         Flags.quit_crc = 1;
  365.                         break;
  366.  
  367.                         /*
  368.                          * Ein Gadget wurde gedrückt und losgelassen.
  369.                          */
  370.                     case IDCMP_GADGETUP:
  371.                         id = ((struct Gadget *) object)->GadgetID;
  372.  
  373.                   HandleHelp((enum RSysNumbers)id);
  374.  
  375.                         switch (id)
  376.                         {
  377.                                 /*
  378.                                  * Falls eine Datei ausgewählt weerden soll, wird ein
  379.                                  * ASL-Filerequester angeboten, mit dem eine Datei
  380.                                  * ausgewählt werden kann.
  381.                                  */
  382.                             case GD_SelectFileGad:
  383.                                 if (GetFile(CRCWnd, NULL, NULL, NULL, "Select File for computing CRC-Sum", "Select") && 
  384.                             exist((char *)_fullpath))
  385.                                 {
  386.                                     strncpy(name, (char *)_fullpath, MAXFULLNAME);
  387.                                     strncpy(shortname, (char *)FilePart((UBYTE *) name), 40);
  388.  
  389.                                     GT_SetGadgetAttrs(CRCGadgets[GD_FileTGad - GD_FileTGad], CRCWnd,
  390.                                                             NULL,
  391.                                                             GTTX_Text, ((strlen(name) <= 21) ?
  392.                                                                             (UBYTE *) name :
  393.                                                                             (UBYTE *) shortname),
  394.                                                             TAG_DONE);
  395.  
  396.                                         /*
  397.                                          * Die Größe der Datei wird berechnet.
  398.                                          */
  399.                                     size = SizeOfFile(name);
  400.                                 }
  401.                                 break;
  402.  
  403.                                 /*
  404.                                  * Der CRC-Modus wird umgesetzt (CRC16 oder CRC32).
  405.                                  */
  406.                             case GD_TypeCRCCYGad:
  407.                                 CRCtype = (int)code;
  408.                                 break;
  409.  
  410.                                 /*
  411.                                  * Die CRC-Summe soll berechnet werden. Die Datei
  412.                                  * wird geöffnet und ausgelesen.
  413.                                  */
  414.                             case GD_ComputeGad:
  415.                                 if (file = Open((UBYTE *) name, MODE_OLDFILE))
  416.                                 {
  417.                                         /*
  418.                                          * Falls die Datei zu groß für eine der beiden
  419.                                          * CRC-Berechnungsarten ist, wird eine Fehlermeldung
  420.                                          * ausgegeben.
  421.                                          */
  422.                                     if (((CRCtype == CRC32) && (size >= ULONG_MAX)) ||
  423.                                          ((CRCtype == CRC16) && (size >= USHRT_MAX)))
  424.                                         ErrorHandle(name, FILE_ERR, SIZE_FAIL, NO_KILL);
  425.                                     else
  426.                                     {
  427.                                             /*
  428.                                              * Die nicht notwendigen Gadgets werden
  429.                                              * ausgeschaltet, die Datei ausgelesen und die
  430.                                              * CRC-Summe berechnet.
  431.                                              */
  432.                                         EnableGadget(CRCWnd, CRCGadgets[GD_TypeCRCCYGad - GD_FileTGad], FALSE);
  433.                                         EnableGadget(CRCWnd, CRCGadgets[GD_SelectFileGad - GD_FileTGad], FALSE);
  434.                                         filebuff = (UBYTE *) MyAllocVec(size + 2, MEMF_CLEAR, NO_KILL);
  435.                                         if (filebuff)
  436.                                         {
  437.                                             if (FRead(file, filebuff, 1L, size) == size)
  438.                                             {
  439.                                                 sum = (*CRCfunc[CRCtype]) (filebuff, size);
  440.  
  441.                                                 sprintf(help, "%lx", (CRCtype ? (WORD) sum : sum));
  442.  
  443.                                                 GT_SetGadgetAttrs(CRCGadgets[GD_CRCTGad - GD_FileTGad], CRCWnd,
  444.                                                                         NULL,
  445.                                                                         GTTX_Text, (UBYTE *) help,
  446.                                                                         TAG_DONE);
  447.                                             }
  448.                                             else
  449.                                                 GT_SetGadgetAttrs(CRCGadgets[GD_FileTGad - GD_FileTGad], CRCWnd,
  450.                                                                         NULL,
  451.                                                                         GTTX_Text, (UBYTE *) field[NO_FILE],
  452.                                                                         TAG_DONE);
  453.  
  454.                                             MyFreeVec(filebuff);
  455.                                         }
  456.  
  457.                                         EnableGadget(CRCWnd, CRCGadgets[GD_TypeCRCCYGad - GD_FileTGad], TRUE);
  458.                                         EnableGadget(CRCWnd, CRCGadgets[GD_SelectFileGad - GD_FileTGad], TRUE);
  459.                                     }
  460.  
  461.                                     Close(file);
  462.                                 }
  463.                                 else ErrorHandle(name, FILE_ERR, OPEN_FAIL, NO_KILL);
  464.  
  465.                                 break;
  466.                         }
  467.                         break;
  468.  
  469.                         /*
  470.                          * Eine Taste wurde gedrückt. War es die Esc-Taste,
  471.                          * wird das Unterprogramm beendet.
  472.                          */
  473.                     case IDCMP_VANILLAKEY:
  474.                         if ((char)code == ESC) Flags.quit_crc = 1;
  475.                         break;
  476.                 }
  477.             }
  478.         } while (NOT(Flags.quit_crc));
  479.  
  480.             /*
  481.              * Das CRC-Window wird geschlossen.
  482.              */
  483.         CloseASysWindow(&CRCWnd, &CRCGList, NULL);
  484.  
  485.             /*
  486.              * Falls das Hauptfenster geöffnet ist, wird es für
  487.              * Eingaben freigegeben und die Statistik im
  488.              * Message-Feld erneuert.
  489.              */
  490.       LockMainWindow(UNLOCK);
  491.     }
  492.  
  493.     return;
  494. }
  495.