Welcome to Schneider / Amstrad CPC Forum. Please login or sign up.

28. March 2024, 16:14:02

Login with username, password and session length

Shoutbox

TFM

2024-01-15, 17:06:57
Momentan billige Farbbänder auf Ebay für PCW

Devilmarkus

2023-07-09, 10:37:40
Zweiter 👋😂🤣

TFM

2023-06-13, 14:21:49
Sommerloch!

TFM

2023-05-30, 17:00:20
Erster ;-)

Recent

Members
Stats
  • Total Posts: 11,654
  • Total Topics: 1,328
  • Online today: 93
  • Online ever: 1,724
  • (16. January 2020, 00:18:45)
Users Online
Users: 0
Guests: 80
Total: 80

80 Guests, 0 Users

Wie Directory eines DSK auslesen

Started by oobdoo, 10. June 2020, 14:21:23

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

TFM

Die Sektornummer einfach hochzählen, wenn es nicht weiter geht, dann mit dem ersten Sektor auf der nächsten Spur weitermachen.
TFM of FutureSoft
http://www.futureos.de --> Das Betriebssystem FutureOS (Update: 20.12.2023)
http://futureos.cpc-live.com/files/LambdaSpeak_RSX_by_TFM.zip --> RSX ROM für LambdaSpeak (Update: 26.12.2021)

Devilmarkus

Im JavaCPC mache ich das so:
(Java Code)

  public static int ChecksumAMSDOS(byte[] pHeader) {
    int Checksum = 0;
    for (int i = 0; i < 67; i++) {
      int CheckSumByte = pHeader[i] & 0xFF;
      Checksum += CheckSumByte;
    }
    return Checksum;
  }
 
  public static boolean CheckAMSDOS(byte[] pHeader) {
    int CalculatedChecksum;
    try {
      CalculatedChecksum = ChecksumAMSDOS(pHeader);
    } catch (Exception e) {
      return false;
    }
    int ChecksumFromHeader = pHeader[67] & 0xFF | (pHeader[68] & 0xFF) << 8;
    if (ChecksumFromHeader == CalculatedChecksum && ChecksumFromHeader != 0) {
      System.out.println("Has AMSDOS header");
      return true;
    }
    System.out.println("Without header");
    return false;
  }
https://cpcwiki.de
Dein Deutsches CPCWiki!

drazil

#17
Hi Oobdoo ich hänge mich mal an deinen Thread dran, da ich dazu auch noch ne Frage habe.

Mein Problem ist der Umgang mit NICHT ASCII files die aber keinen Header haben.

Um diese zu exportieren gehe ich momentan folgendermassen vor.
Die FileSize nehme ich aus dem Directoryeintrag, da ja kein Header vorhanden ist. Ist aber nicht die korrekte Grösse.
Anschliessen prüfe ich noch die ersten 100 Bytes auf Character.isAlphabetic. Wenn das nicht so ist wird eine normale Binärdatei gelesen.
Gibts da einen offizielleren Weg, oder wird das tatsächlich so ähnlich geprüft?
Ich habe keine anderen Flags im Directoryeintrag gefunden mit denen ich das steuern könnte.

Beste Grüße
Guido

TFM

Da gehst Du schon richtig vor.
- Test auf Header. Wenn ja, dann ist es BIN oder BAS Datei
- Wenn nein, dann ist es Text oder z.B. ein CP/M Kommando (*.COM Dateien)

Zur Bestimmung der Länge kann man die Anzahl der 128 Byte Records aus dem DIRectory ermitteln. Das ist dann auf die nächsten 128 Bytes aufgerundet.

Rekord-Anzahl ermitteln:
------------------------
- Record_Anzahl = (Byte_&0C) * 128 + (Byte_&0F)


Im Data Becker Floppy Buch ist das gut erklärt, ist auch hier im Forum (wImre).
TFM of FutureSoft
http://www.futureos.de --> Das Betriebssystem FutureOS (Update: 20.12.2023)
http://futureos.cpc-live.com/files/LambdaSpeak_RSX_by_TFM.zip --> RSX ROM für LambdaSpeak (Update: 26.12.2021)

drazil

Hi, wo finde ich denn das Floppbuch hier im Forum?

Sorry, schon gefunden.

dettus

Vielleicht helfen dir ja meine kleinen Tools weiter.

Erstmal ein dskread.c, damit mache ich aus einem DSK ein CPM file.

/*
Copyright 2020, dettus@dettus.net

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this
   list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define PARSE_INT32BE(ptr,idx)  (\
        (((unsigned int)((ptr)[((idx)+0)])&0xff)<<24)   |\
        (((unsigned int)((ptr)[((idx)+1)])&0xff)<<16)   |\
        (((unsigned int)((ptr)[((idx)+2)])&0xff)<< 8)   |\
        (((unsigned int)((ptr)[((idx)+3)])&0xff)<< 0)   |\
        0)
#define PARSE_INT16BE(ptr,idx)  (\
        (((unsigned int)((ptr)[((idx)+0)])&0xff)<< 8)   |\
        (((unsigned int)((ptr)[((idx)+1)])&0xff)<< 0)   |\
        0)


#define PARSE_INT32LE(ptr,idx)  (\
        (((unsigned int)((ptr)[((idx)+3)])&0xff)<<24)   |\
        (((unsigned int)((ptr)[((idx)+2)])&0xff)<<16)   |\
        (((unsigned int)((ptr)[((idx)+1)])&0xff)<< 8)   |\
        (((unsigned int)((ptr)[((idx)+0)])&0xff)<< 0)   |\
        0)
#define PARSE_INT16LE(ptr,idx)  (\
        (((unsigned int)((ptr)[((idx)+1)])&0xff)<< 8)   |\
        (((unsigned int)((ptr)[((idx)+0)])&0xff)<< 0)   |\
        0)



unsigned char buf[1<<20];
int main(int argc,char** argv)
{
        FILE *f;
        int dsksize;
        int i,j;
        int tracknum;
        int sidenum;
        int tracksize;
        int idx;

        f=fopen(argv[1],"rb");
        dsksize=fread(buf,sizeof(char),sizeof(buf),f);
        fclose(f);

        f=fopen(argv[2],"wb");

        printf("dsksize:%d\n",dsksize);
        printf("<<magic:");
        for (i=0;i<=0x21;i++)
        {
                printf("%c",buf[i]);
        }
        printf(">>");
        printf("<<name of creator:");
        for (i=0x22;i<=0x2f;i++) printf("%c",buf[i]);
        printf(">>");
        printf("<<number of tracks:%d>>",buf[0x30]);
        printf("<<number of sides:%d>>",buf[0x31]);
        printf("<<size of a track:%d>>",PARSE_INT16LE(buf,0x32));
        printf("\n");
        printf("-------------------------\n");
        tracknum=buf[0x30];
        sidenum=buf[0x31];
        tracksize=PARSE_INT16LE(buf,0x32);

        idx=256;
        for (i=0;i<tracknum*sidenum;i++)
        {
                int idx0;
                int sectorsize;
                int sectornum;
                int sectorids[16]={0};
                int order[16]={0};

                idx0=idx;
                printf("\x1b[0;30;47mtrack:%d side:%d\x1b[0m\n",tracknum/sidenum,tracknum%sidenum);
                printf("magic:      ");
                for (j=0;j<0x0c;j++) printf("%c",buf[idx++]);
                printf("\n");
                idx+=4;         // 0x0c-0x0f: unused
                printf("track:      %d\n",buf[idx++]);
                printf("side:       %d\n",buf[idx++]);
                idx+=2; //0x12-0x13: unused
                sectorsize=buf[idx];
                printf("sector size:%d\n",buf[idx++]);
                sectornum=buf[idx];
                printf("sector num: %d\n",buf[idx++]);
                printf("gap3 length:%d\n",buf[idx++]);
                printf("filler byte:%d\n",buf[idx++]);
                for (j=0;j<sectornum;j++)
                {
                        order[j]=j;
                        printf("   %d> track:      %d\n",j,buf[idx++]);
                        printf("   %d> side:       %d\n",j,buf[idx++]);
                        sectorids[j]=buf[idx];
                        printf("   %d> sectorID:   %d\n",j,buf[idx++]);
                        sectorsize=128<<buf[idx];
                        printf("   %d> sectorsize: %d --> %d bytes\n",j,buf[idx++],sectorsize);
                        printf("   %d> FDC status1:%d\n",j,buf[idx++]);
                        printf("   %d> FDC status2:%d\n",j,buf[idx++]);
                        idx+=2; // 06-07: unused

                }
                for (j=0;j<sectornum-1;j++)
                {
                        int k;
                        for (k=j+1;k<sectornum;k++)
                        {
                                if (sectorids[order[j]]>sectorids[order[k]])
                                {
                                        int x;
                                        x=order[j];
                                        order[j]=order[k];
                                        order[k]=x;
                                }
                        }
                }
                printf("track %2d> order ",i);
                for (j=0;j<sectornum;j++)
                {
                        printf("%d ",order[j]);
                }
                printf("\n");
                idx=idx0+0x100;
                for (j=0;j<sectornum;j++)
                {
                        printf("@%06x   ",idx+order[j]*sectorsize);
                        printf("writing sector %d id=%d\n",order[j],sectorids[order[j]]);
                        fwrite(&buf[idx+order[j]*sectorsize],sizeof(char),sectorsize,f);
                }

                idx=idx0+tracksize;
        }
        fclose(f);
}


Anschliessend verwende ich mein cpmextract.c, um die Dateien aus dem CPM Filesystem zu extrahieren

/*
Copyright 2020, dettus@dettus.net

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this
   list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
// http://www.seasip.info/Cpm/format22.html
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define PARSE_INT32BE(ptr,idx)  (\
        (((unsigned int)((ptr)[((idx)+0)])&0xff)<<24)   |\
        (((unsigned int)((ptr)[((idx)+1)])&0xff)<<16)   |\
        (((unsigned int)((ptr)[((idx)+2)])&0xff)<< 8)   |\
        (((unsigned int)((ptr)[((idx)+3)])&0xff)<< 0)   |\
        0)
#define PARSE_INT16BE(ptr,idx)  (\
        (((unsigned int)((ptr)[((idx)+0)])&0xff)<< 8)   |\
        (((unsigned int)((ptr)[((idx)+1)])&0xff)<< 0)   |\
        0)


#define PARSE_INT32LE(ptr,idx)  (\
        (((unsigned int)((ptr)[((idx)+3)])&0xff)<<24)   |\
        (((unsigned int)((ptr)[((idx)+2)])&0xff)<<16)   |\
        (((unsigned int)((ptr)[((idx)+1)])&0xff)<< 8)   |\
        (((unsigned int)((ptr)[((idx)+0)])&0xff)<< 0)   |\
        0)
#define PARSE_INT16LE(ptr,idx)  (\
        (((unsigned int)((ptr)[((idx)+1)])&0xff)<< 8)   |\
        (((unsigned int)((ptr)[((idx)+0)])&0xff)<< 0)   |\
        0)


#define BLOCKSIZE       1024

unsigned char buf[1<<20];
int main(int argc,char** argv)
{
        FILE *f;
        int bufsize;
        int i,j;
        int idx;
        int firstblock;
        int entrycnt;
        int attrs;
        int extent;
        char filename[16]={0};
        char lastfilename[16]={0};


        f=fopen(argv[1],"rb");
        bufsize=fread(buf,sizeof(char),sizeof(buf),f);
        fclose(f);
        f=NULL;
        firstblock=bufsize/BLOCKSIZE;

        idx=0;
        entrycnt=0;


        while (idx<firstblock*BLOCKSIZE)
        {
                if ((buf[idx]&0xf0)==0)
                {
                        printf("%2d> ",entrycnt);
                        for (i=0;i<32;i++) printf("%02x ",buf[idx+i]);
                        printf("user: %x  ",buf[idx]&0xf);
                        idx++;
                        j=0;
                        filename[j++]='_';
                        for (i=0;i<11;i++)
                        {
                                unsigned char c;
                                c=buf[idx++]&0x7f;
                                if (i==8) filename[j++]='.';
                                if (c!=' ') filename[j++]=c;
                                filename[j]=0;
                        }
                        printf("[%s]",filename);
                        if (memcmp(filename,lastfilename,16))
                        {
                                if (f!=NULL) fclose(f);
                                memcpy(lastfilename,filename,16);
                                f=fopen(filename,"wb");
                        }
                        extent=buf[idx++];      // EX
                        idx++;          //      S1=0
                        extent=buf[idx++]<<8;   // S2 little endian
                        extent*=128;
                        extent+=buf[idx++];     // rc
                        printf("extent:%6d ",extent);
                        printf("{");
                        for (i=0;i<16;i++)
                        {
                                int block;
                                block=buf[idx++];
                                if (block && block<firstblock) firstblock=block;
                                printf("%02X ",block);
                                if (block) fwrite(&buf[block*BLOCKSIZE],sizeof(char),BLOCKSIZE,f);
                        }
                        printf("}");
                        printf("\n");

                        entrycnt++;
                } else {
                        idx+=32;
                }
        }
        if (f!=NULL) fclose(f);
}


Computer science is not about using a computer. It is about unleashing its power.