org-hyperion-cules/tapemap.c

/* TAPEMAP.C   (c) Copyright Jay Maynard, 2000-2006                  */
/*              Map AWSTAPE format tape image                        */

/*-------------------------------------------------------------------*/
/* This program reads an AWSTAPE format tape image file and produces */
/* a map of the tape, printing any standard label records it finds.  */
/*-------------------------------------------------------------------*/

#include "hstdinc.h"

#include "hercules.h"

/*-------------------------------------------------------------------*/
/* Structure definition for AWSTAPE block header                     */
/*-------------------------------------------------------------------*/
typedef struct _AWSTAPE_BLKHDR {
        HWORD   curblkl;                /* Length of this block      */
        HWORD   prvblkl;                /* Length of previous block  */
        BYTE    flags1;                 /* Flags byte 1              */
        BYTE    flags2;                 /* Flags byte 2              */
    } AWSTAPE_BLKHDR;

/* Definitions for AWSTAPE_BLKHDR flags byte 1 */
#define AWSTAPE_FLAG1_NEWREC    0x80    /* Start of new record       */
#define AWSTAPE_FLAG1_TAPEMARK  0x40    /* Tape mark                 */
#define AWSTAPE_FLAG1_ENDREC    0x20    /* End of record             */

/*-------------------------------------------------------------------*/
/* Static data areas                                                 */
/*-------------------------------------------------------------------*/
static BYTE vollbl[] = "\xE5\xD6\xD3";  /* EBCDIC characters "VOL"   */
static BYTE hdrlbl[] = "\xC8\xC4\xD9";  /* EBCDIC characters "HDR"   */
static BYTE eoflbl[] = "\xC5\xD6\xC6";  /* EBCDIC characters "EOF"   */
static BYTE eovlbl[] = "\xC5\xD6\xE5";  /* EBCDIC characters "EOV"   */
static BYTE buf[65536];

#ifdef EXTERNALGUI
/* Report progress every this many bytes */
#define PROGRESS_MASK (~0x3FFFF /* 256K */)
/* How many bytes we've read so far. */
long  curpos = 0;
long  prevpos = 0;
#endif /*EXTERNALGUI*/

/*-------------------------------------------------------------------*/
/* TAPEMAP main entry point                                          */
/*-------------------------------------------------------------------*/
int main (int argc, char *argv[])
{
int             i;                      /* Array subscript           */
int             len;                    /* Block length              */
int             prevlen;                /* Previous block length     */
char           *filename;               /* -> Input file name        */
int             infd = -1;              /* Input file descriptor     */
int             fileno;                 /* Tape file number          */
int             blkcount;               /* Block count               */
int             curblkl;                /* Current block length      */
int             minblksz;               /* Minimum block size        */
int             maxblksz;               /* Maximum block size        */
BYTE            labelrec[81];           /* Standard label (ASCIIZ)   */
AWSTAPE_BLKHDR  awshdr;                 /* AWSTAPE block header      */
BYTE            pathname[MAX_PATH];     /* file path in host format  */

    set_codepage(NULL);

#ifdef EXTERNALGUI
    if (argc >= 1 && strncmp(argv[argc-1],"EXTERNALGUI",11) == 0)
    {
        extgui = 1;
        argc--;
        setvbuf(stderr, NULL, _IONBF, 0);
        setvbuf(stdout, NULL, _IONBF, 0);
    }
#endif /*EXTERNALGUI*/

    /* Display the program identification message */
    display_version (stderr, "Hercules tape map program ", FALSE);

    /* The only argument is the tape image file name */
    if (argc == 2 && argv[1] != NULL)
    {
        filename = argv[1];
    }
    else
    {
        printf ("Usage: tapemap filename\n");
        exit (1);
    }

    /* Open the tape device */
    hostpath(pathname, filename, sizeof(pathname));
    infd = open (pathname, O_RDONLY | O_BINARY);
    if (infd < 0)
    {
        printf ("tapemap: Error opening %s: %s\n",
                filename, strerror(errno));
        exit (2);
    }

    /* Read blocks from the input file and report on them */
    fileno = 1;
    blkcount = 0;
    minblksz = 0;
    maxblksz = 0;
    len = 0;

    while (1)
    {
#ifdef EXTERNALGUI
        if (extgui)
        {
            /* Report progress every nnnK */
            if( ( curpos & PROGRESS_MASK ) != ( prevpos & PROGRESS_MASK ) )
            {
                prevpos = curpos;
                fprintf( stderr, "IPOS=%ld\n", curpos );
            }
        }
#endif /*EXTERNALGUI*/
        /* Save previous block length */
        prevlen = len;

        /* Read a block from the tape */
        len = read (infd, buf, sizeof(AWSTAPE_BLKHDR));
#ifdef EXTERNALGUI
        if (extgui) curpos += len;
#endif /*EXTERNALGUI*/
        if (len < 0)
        {
            printf ("tapemap: error reading header block from %s: %s\n",
                    filename, strerror(errno));
            exit (3);
        }

        /* Did we finish too soon? */
        if ((len > 0) && (len < (int)sizeof(AWSTAPE_BLKHDR)))
        {
            printf ("tapemap: incomplete block header on %s\n",
                    filename);
            exit(4);
        }
        
        /* Check for end of tape. */
        if (len == 0)
        {
            printf ("End of tape.\n");
            break;
        }
        
        /* Parse the block header */
        memcpy(&awshdr, buf, sizeof(AWSTAPE_BLKHDR));
        
        /* Tapemark? */
        if ((awshdr.flags1 & AWSTAPE_FLAG1_TAPEMARK) != 0)
        {
            /* Print summary of current file */
            printf ("File %u: Blocks=%u, block size min=%u, max=%u\n",
                    fileno, blkcount, minblksz, maxblksz);

            /* Reset counters for next file */
            fileno++;
            minblksz = 0;
            maxblksz = 0;
            blkcount = 0;

        }
        else /* if(tapemark) */
        {
            /* Count blocks and block sizes */
            blkcount++;
            curblkl = awshdr.curblkl[0] + (awshdr.curblkl[1] << 8);
            if (curblkl > maxblksz) maxblksz = curblkl;
            if (minblksz == 0 || curblkl < minblksz) minblksz = curblkl;

            /* Read the data block. */
            len = read (infd, buf, curblkl);
#ifdef EXTERNALGUI
            if (extgui) curpos += len;
#endif /*EXTERNALGUI*/
            if (len < 0)
            {
                printf ("tapemap: error reading data block from %s: %s\n",
                        filename, strerror(errno));
                exit (5);
            }

            /* Did we finish too soon? */
            if ((len > 0) && (len < curblkl))
            {
                printf ("tapemap: incomplete final data block on %s, "
                        "expected %d bytes, got %d\n",
                        filename, curblkl, len);
                exit(6);
            }
        
            /* Check for end of tape */
            if (len == 0)
            {
                printf ("tapemap: header block with no data on %s\n",
                        filename);
                exit(7);
            }
        
            /* Print standard labels */
            if (len == 80 && blkcount < 4
                && (memcmp(buf, vollbl, 3) == 0
                    || memcmp(buf, hdrlbl, 3) == 0
                    || memcmp(buf, eoflbl, 3) == 0
                    || memcmp(buf, eovlbl, 3) == 0))
            {
                for (i=0; i < 80; i++)
                    labelrec[i] = guest_to_host(buf[i]);
                labelrec[i] = '\0';
                printf ("%s\n", labelrec);
            }
            
        } /* end if(tapemark) */

    } /* end while */

    /* Close files and exit */
    close (infd);

    return 0;

} /* end function main */