/
awstape.c
771 lines (641 loc) · 28.4 KB
/
awstape.c
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/* AWSTAPE.C (c) Copyright Roger Bowler, 1999-2012 */
/* Hercules Tape Device Handler for AWSTAPE */
/* */
/* Released under "The Q Public License Version 1" */
/* (http://www.hercules-390.org/herclic.html) as modifications to */
/* Hercules. */
/* Original Author: Roger Bowler */
/* Prime Maintainer: Ivan Warren */
/* Secondary Maintainer: "Fish" (David B. Trout) */
/*-------------------------------------------------------------------*/
/* This module contains the AWSTAPE emulated tape format support. */
/* The subroutines in this module are called by the general tape */
/* device handler (tapedev.c) when the tape format is AWSTAPE. */
/*-------------------------------------------------------------------*/
/*-------------------------------------------------------------------*/
/* Messages issued by this module are prefixed HHCTA1nn */
/*-------------------------------------------------------------------*/
#include "hstdinc.h"
#include "hercules.h" /* need Hercules control blocks */
#include "tapedev.h" /* Main tape handler header file */
//#define ENABLE_TRACING_STMTS 1 // (Fish: DEBUGGING)
//#include "dbgtrace.h" // (Fish: DEBUGGING)
/*********************************************************************/
/* START OF ORIGINAL AWS FUNCTIONS (ISW Additions) */
/*********************************************************************/
/*-------------------------------------------------------------------*/
/* Close an AWSTAPE format file */
/* New Function added by ISW for consistency with other medias */
/*-------------------------------------------------------------------*/
void close_awstape (DEVBLK *dev)
{
if( dev->fd >= 0 )
{
WRMSG (HHC00201, "I", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws");
close(dev->fd);
}
strlcpy(dev->filename, TAPE_UNLOADED, sizeof(dev->filename));
dev->fd=-1;
dev->blockid = 0;
dev->fenced = 0;
return;
}
/*-------------------------------------------------------------------*/
/* Rewinds an AWS Tape format file */
/* New Function added by ISW for consistency with other medias */
/*-------------------------------------------------------------------*/
int rewind_awstape (DEVBLK *dev,BYTE *unitstat,BYTE code)
{
off_t rcoff;
rcoff=lseek(dev->fd,0,SEEK_SET);
if(rcoff<0)
{
build_senseX(TAPE_BSENSE_REWINDFAILED,dev,unitstat,code);
return -1;
}
dev->nxtblkpos=0;
dev->prvblkpos=-1;
dev->curfilen=1;
dev->blockid=0;
dev->fenced = 0;
return 0;
}
/*-------------------------------------------------------------------*/
/* Determines if a tape has passed a virtual EOT marker */
/* New Function added by ISW for consistency with other medias */
/*-------------------------------------------------------------------*/
int passedeot_awstape (DEVBLK *dev)
{
if( dev->nxtblkpos == 0 )
{
dev->eotwarning = 0;
return 0;
}
if( dev->tdparms.maxsize == 0 )
{
dev->eotwarning = 0;
return 0;
}
if( dev->nxtblkpos + dev->eotmargin > dev->tdparms.maxsize )
{
dev->eotwarning = 1;
return 1;
}
dev->eotwarning = 0;
return 0;
}
/*********************************************************************/
/* START OF ORIGINAL RB AWS FUNCTIONS */
/*********************************************************************/
/*-------------------------------------------------------------------*/
/* Open an AWSTAPE format file */
/* */
/* If successful, the file descriptor is stored in the device block */
/* and the return value is zero. Otherwise the return value is -1. */
/*-------------------------------------------------------------------*/
int open_awstape (DEVBLK *dev, BYTE *unitstat,BYTE code)
{
int rc = -1; /* Return code */
char pathname[MAX_PATH]; /* file path in host format */
/* Check for no tape in drive */
if (!strcmp (dev->filename, TAPE_UNLOADED))
{
build_senseX(TAPE_BSENSE_TAPEUNLOADED,dev,unitstat,code);
return -1;
}
/* Open the AWSTAPE file */
hostpath(pathname, dev->filename, sizeof(pathname));
if(!dev->tdparms.logical_readonly)
{
rc = HOPEN (pathname, O_RDWR | O_BINARY, S_IRUSR | S_IWUSR | S_IRGRP );
if ( rc < 0 && !sysblk.noautoinit )
{
rc = HOPEN( pathname, O_RDWR | O_BINARY | O_CREAT, S_IRUSR | S_IWUSR | S_IRGRP );
if ( rc >= 0 )
{
int tmp_fd = dev->fd;
int ret_code = 0;
dev->fd = rc;
WRMSG( HHC00235, "I", SSID_TO_LCSS(dev->ssid),
dev->devnum, dev->filename, "aws" );
ret_code = write_awsmark( dev, unitstat, code );
if ( ret_code >= 0 )
ret_code = write_awsmark( dev, unitstat, code );
if ( ret_code < 0 )
{
dev->fd = tmp_fd;
rc = ret_code;
}
}
}
}
/* If file is read-only, attempt to open again */
if (dev->tdparms.logical_readonly || (rc < 0 && (EROFS == errno || EACCES == errno)))
{
dev->readonly = 1;
rc = HOPEN (pathname, O_RDONLY | O_BINARY, S_IRUSR | S_IRGRP );
}
/* Check for successful open */
if (rc < 0)
{
WRMSG (HHC00205, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "open()", strerror(errno));
strlcpy( dev->filename, TAPE_UNLOADED, sizeof(dev->filename) );
build_senseX(TAPE_BSENSE_TAPELOADFAIL,dev,unitstat,code);
return -1;
}
/* Store the file descriptor in the device block */
dev->fd = rc;
rc=rewind_awstape(dev,unitstat,code);
return rc;
} /* end function open_awstape */
/*-------------------------------------------------------------------*/
/* Read an AWSTAPE block header */
/* */
/* If successful, return value is zero, and buffer contains header. */
/* If error, return value is -1 and unitstat is set to CE+DE+UC */
/*-------------------------------------------------------------------*/
int readhdr_awstape (DEVBLK *dev, off_t blkpos,
AWSTAPE_BLKHDR *buf, BYTE *unitstat,BYTE code)
{
int rc; /* Return code */
off_t rcoff; /* Return code from lseek() */
/* Reposition file to the requested block header */
rcoff = lseek (dev->fd, blkpos, SEEK_SET);
if (rcoff < 0)
{
/* Handle seek error condition */
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "lseek()", blkpos, strerror(errno));
/* Set unit check with equipment check */
build_senseX(TAPE_BSENSE_LOCATEERR,dev,unitstat,code);
return -1;
}
/* Read the 6-byte block header */
rc = read (dev->fd, buf, sizeof(AWSTAPE_BLKHDR));
/* Handle read error condition */
if (rc < 0)
{
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "read()", blkpos, strerror(errno));
/* Set unit check with equipment check */
build_senseX(TAPE_BSENSE_READFAIL,dev,unitstat,code);
return -1;
}
/* Handle end of file (uninitialized tape) condition */
if (rc == 0)
{
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "readhdr_awstape()", blkpos, "end of file (uninitialized tape)");
/* Set unit exception with tape indicate (end of tape) */
build_senseX(TAPE_BSENSE_EMPTYTAPE,dev,unitstat,code);
return -1;
}
/* Handle end of file within block header */
if (rc < (int)sizeof(AWSTAPE_BLKHDR))
{
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "readhdr_awstape()", blkpos, "unexpected end of file");
build_senseX(TAPE_BSENSE_BLOCKSHORT,dev,unitstat,code);
return -1;
}
/* Successful return */
return 0;
} /* end function readhdr_awstape */
/*-------------------------------------------------------------------*/
/* Read a block from an AWSTAPE format file */
/* */
/* The block may be formed of one or more block segments each */
/* preceded by an AWSTAPE block header. The ENDREC flag in the */
/* block header indicates the final segment of the block. */
/* */
/* If successful, return value is block length read. */
/* If a tapemark was read, the return value is zero, and the */
/* current file number in the device block is incremented. */
/* If error, return value is -1 and unitstat is set to CE+DE+UC */
/*-------------------------------------------------------------------*/
int read_awstape (DEVBLK *dev, BYTE *buf, BYTE *unitstat,BYTE code)
{
int rc; /* Return code */
AWSTAPE_BLKHDR awshdr; /* AWSTAPE block header */
off_t blkpos; /* Offset of block header */
int blklen = 0; /* Total length of block */
U16 seglen; /* Data length of segment */
/* Initialize current block position */
blkpos = dev->nxtblkpos;
/* Read block segments until end of block */
do
{
/* Read the 6-byte block header */
rc = readhdr_awstape (dev, blkpos, &awshdr, unitstat,code);
if (rc < 0) return -1;
/* Extract the segment length from the block header */
seglen = ((U16)(awshdr.curblkl[1]) << 8)
| awshdr.curblkl[0];
/* Calculate the offset of the next block segment */
blkpos += sizeof(awshdr) + seglen;
/* Check that block length will not exceed buffer size */
if (blklen + seglen > MAX_BLKLEN)
{
WRMSG (HHC00202, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws",
(int)MAX_BLKLEN, blkpos);
/* Set unit check with data check */
build_senseX(TAPE_BSENSE_READFAIL,dev,unitstat,code);
return -1;
}
/* Check that tapemark blocksize is zero */
if ((awshdr.flags1 & AWSTAPE_FLAG1_TAPEMARK)
&& blklen + seglen > 0)
{
WRMSG (HHC00203, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", blkpos);
/* Set unit check with data check */
build_senseX(TAPE_BSENSE_READFAIL,dev,unitstat,code);
return -1;
}
/* Exit loop if this is a tapemark */
if (awshdr.flags1 & AWSTAPE_FLAG1_TAPEMARK)
break;
/* Read data block segment from tape file */
rc = read (dev->fd, buf+blklen, seglen);
/* Handle read error condition */
if (rc < 0)
{
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "read()", blkpos, strerror(errno));
/* Set unit check with equipment check */
build_senseX(TAPE_BSENSE_READFAIL,dev,unitstat,code);
return -1;
}
/* Handle end of file within data block */
if (rc < seglen)
{
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "read_awstape()", blkpos, "end of file within data block");
/* Set unit check with data check and partial record */
build_senseX(TAPE_BSENSE_BLOCKSHORT,dev,unitstat,code);
return -1;
}
/* Accumulate the total block length */
blklen += seglen;
} while ((awshdr.flags1 & AWSTAPE_FLAG1_ENDREC) == 0);
/* Calculate the offsets of the next and previous blocks */
dev->prvblkpos = dev->nxtblkpos;
dev->nxtblkpos = blkpos;
/* Increment the block number */
dev->blockid++;
/* Increment file number and return zero if tapemark was read */
if (blklen == 0)
{
dev->curfilen++;
return 0; /* UX will be set by caller */
}
/* Return block length */
return blklen;
} /* end function read_awstape */
/*-------------------------------------------------------------------*/
/* Write a block to an AWSTAPE format file */
/* */
/* If successful, return value is zero. */
/* If error, return value is -1 and unitstat is set to CE+DE+UC */
/*-------------------------------------------------------------------*/
int write_awstape (DEVBLK *dev, BYTE *buf, U16 blklen,
BYTE *unitstat,BYTE code)
{
int rc; /* Return code */
off_t rcoff; /* Return code from lseek() */
AWSTAPE_BLKHDR awshdr; /* AWSTAPE block header */
off_t blkpos; /* Offset of block header */
U16 prvblkl; /* Length of previous block */
/* Initialize current block position and previous block length */
blkpos = dev->nxtblkpos;
prvblkl = 0;
/* Determine previous block length if not at start of tape */
if (dev->nxtblkpos > 0)
{
/* Reread the previous block header */
rc = readhdr_awstape (dev, dev->prvblkpos, &awshdr, unitstat,code);
if (rc < 0) return -1;
/* Extract the block length from the block header */
prvblkl = ((U16)(awshdr.curblkl[1]) << 8)
| awshdr.curblkl[0];
/* Recalculate the offset of the next block */
blkpos = dev->prvblkpos + sizeof(awshdr) + prvblkl;
}
/* Reposition file to the new block header */
rcoff = lseek (dev->fd, blkpos, SEEK_SET);
if (rcoff < 0)
{
/* Handle seek error condition */
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "lseek()", blkpos, strerror(errno));
/* Set unit check with equipment check */
build_senseX(TAPE_BSENSE_LOCATEERR,dev,unitstat,code);
return -1;
}
/* ISW: Determine if we are passed maxsize */
if(dev->tdparms.maxsize>0)
{
if((off_t)(dev->nxtblkpos+blklen+sizeof(awshdr)) > dev->tdparms.maxsize)
{
build_senseX(TAPE_BSENSE_ENDOFTAPE,dev,unitstat,code);
return -1;
}
}
/* ISW: End of virtual physical EOT determination */
/* Build the 6-byte block header */
awshdr.curblkl[0] = blklen & 0xFF;
awshdr.curblkl[1] = (blklen >> 8) & 0xFF;
awshdr.prvblkl[0] = prvblkl & 0xFF;
awshdr.prvblkl[1] = (prvblkl >>8) & 0xFF;
awshdr.flags1 = AWSTAPE_FLAG1_NEWREC | AWSTAPE_FLAG1_ENDREC;
awshdr.flags2 = 0;
/* Write the block header */
rc = write (dev->fd, &awshdr, sizeof(awshdr));
if (rc < (int)sizeof(awshdr))
{
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "write()", blkpos, strerror(errno));
if(errno==ENOSPC)
{
/* Disk FULL */
build_senseX(TAPE_BSENSE_ENDOFTAPE,dev,unitstat,code);
return -1;
}
/* Set unit check with equipment check */
build_senseX(TAPE_BSENSE_WRITEFAIL,dev,unitstat,code);
return -1;
}
/* Calculate the offsets of the next and previous blocks */
dev->nxtblkpos = blkpos + sizeof(awshdr) + blklen;
dev->prvblkpos = blkpos;
/* Write the data block */
rc = write (dev->fd, buf, blklen);
if (rc < blklen)
{
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "write()", blkpos, strerror(errno));
if(errno==ENOSPC)
{
/* Disk FULL */
build_senseX(TAPE_BSENSE_ENDOFTAPE,dev,unitstat,code);
return -1;
}
/* Set unit check with equipment check */
build_senseX(TAPE_BSENSE_WRITEFAIL,dev,unitstat,code);
return -1;
}
dev->blockid++;
/* Set new physical EOF */
do rc = ftruncate( dev->fd, dev->nxtblkpos );
while (EINTR == rc);
if (rc != 0)
{
/* Handle write error condition */
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "ftruncate()", blkpos, strerror(errno));
/* Set unit check with equipment check */
build_senseX(TAPE_BSENSE_WRITEFAIL,dev,unitstat,code);
return -1;
}
/* Return normal status */
return 0;
} /* end function write_awstape */
/*-------------------------------------------------------------------*/
/* Write a tapemark to an AWSTAPE format file */
/* */
/* If successful, return value is zero. */
/* If error, return value is -1 and unitstat is set to CE+DE+UC */
/*-------------------------------------------------------------------*/
int write_awsmark (DEVBLK *dev, BYTE *unitstat,BYTE code)
{
int rc; /* Return code */
off_t rcoff; /* Return code from lseek() */
AWSTAPE_BLKHDR awshdr; /* AWSTAPE block header */
off_t blkpos; /* Offset of block header */
U16 prvblkl; /* Length of previous block */
/* Initialize current block position and previous block length */
blkpos = dev->nxtblkpos;
prvblkl = 0;
/* Determine previous block length if not at start of tape */
if (dev->nxtblkpos > 0)
{
/* Reread the previous block header */
rc = readhdr_awstape (dev, dev->prvblkpos, &awshdr, unitstat,code);
if (rc < 0) return -1;
/* Extract the block length from the block header */
prvblkl = ((U16)(awshdr.curblkl[1]) << 8)
| awshdr.curblkl[0];
/* Recalculate the offset of the next block */
blkpos = dev->prvblkpos + sizeof(awshdr) + prvblkl;
}
/* Reposition file to the new block header */
rcoff = lseek (dev->fd, blkpos, SEEK_SET);
if (rcoff < 0)
{
/* Handle seek error condition */
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "lseek()", blkpos, strerror(errno));
build_senseX(TAPE_BSENSE_LOCATEERR,dev,unitstat,code);
return -1;
}
/* ISW: Determine if we are passed maxsize */
if(dev->tdparms.maxsize>0)
{
if((off_t)(dev->nxtblkpos+sizeof(awshdr)) > dev->tdparms.maxsize)
{
build_senseX(TAPE_BSENSE_ENDOFTAPE,dev,unitstat,code);
return -1;
}
}
/* ISW: End of virtual physical EOT determination */
/* Build the 6-byte block header */
awshdr.curblkl[0] = 0;
awshdr.curblkl[1] = 0;
awshdr.prvblkl[0] = prvblkl & 0xFF;
awshdr.prvblkl[1] = (prvblkl >>8) & 0xFF;
awshdr.flags1 = AWSTAPE_FLAG1_TAPEMARK;
awshdr.flags2 = 0;
/* Write the block header */
rc = write (dev->fd, &awshdr, sizeof(awshdr));
if (rc < (int)sizeof(awshdr))
{
/* Handle write error condition */
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "write()", blkpos, strerror(errno));
build_senseX(TAPE_BSENSE_WRITEFAIL,dev,unitstat,code);
return -1;
}
dev->blockid++;
/* Calculate the offsets of the next and previous blocks */
dev->nxtblkpos = blkpos + sizeof(awshdr);
dev->prvblkpos = blkpos;
/* Set new physical EOF */
do rc = ftruncate( dev->fd, dev->nxtblkpos );
while (EINTR == rc);
if (rc != 0)
{
/* Handle write error condition */
WRMSG (HHC00204, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "ftruncate()", blkpos, strerror(errno));
/* Set unit check with equipment check */
build_senseX(TAPE_BSENSE_WRITEFAIL,dev,unitstat,code);
return -1;
}
/* Return normal status */
return 0;
} /* end function write_awsmark */
/*-------------------------------------------------------------------*/
/* Synchronize an AWSTAPE format file (i.e. flush buffers to disk) */
/* */
/* If successful, return value is zero. */
/* If error, return value is -1 and unitstat is set to CE+DE+UC */
/*-------------------------------------------------------------------*/
int sync_awstape (DEVBLK *dev, BYTE *unitstat,BYTE code)
{
/* Unit check if tape is write-protected */
if (dev->readonly)
{
build_senseX(TAPE_BSENSE_WRITEPROTECT,dev,unitstat,code);
return -1;
}
/* Perform sync. Return error on failure. */
if (fdatasync( dev->fd ) < 0)
{
/* Log the error */
WRMSG (HHC00205, "E", SSID_TO_LCSS(dev->ssid), dev->devnum, dev->filename, "aws", "fdatasync()", strerror(errno));
/* Set unit check with equipment check */
build_senseX(TAPE_BSENSE_WRITEFAIL,dev,unitstat,code);
return -1;
}
/* Return normal status */
return 0;
} /* end function sync_awstape */
/*-------------------------------------------------------------------*/
/* Forward space over next block of AWSTAPE format file */
/* */
/* If successful, return value is the length of the block skipped. */
/* If the block skipped was a tapemark, the return value is zero, */
/* and the current file number in the device block is incremented. */
/* If error, return value is -1 and unitstat is set to CE+DE+UC */
/*-------------------------------------------------------------------*/
int fsb_awstape (DEVBLK *dev, BYTE *unitstat,BYTE code)
{
int rc; /* Return code */
AWSTAPE_BLKHDR awshdr; /* AWSTAPE block header */
off_t blkpos; /* Offset of block header */
int blklen = 0; /* Total length of block */
U16 seglen; /* Data length of segment */
/* Initialize current block position */
blkpos = dev->nxtblkpos;
/* Read block segments until end of block */
do
{
/* Read the 6-byte block header */
rc = readhdr_awstape (dev, blkpos, &awshdr, unitstat,code);
if (rc < 0) return -1;
/* Extract the block length from the block header */
seglen = ((U16)(awshdr.curblkl[1]) << 8)
| awshdr.curblkl[0];
/* Calculate the offset of the next block segment */
blkpos += sizeof(awshdr) + seglen;
/* Accumulate the total block length */
blklen += seglen;
/* Exit loop if this is a tapemark */
if (awshdr.flags1 & AWSTAPE_FLAG1_TAPEMARK)
break;
} while ((awshdr.flags1 & AWSTAPE_FLAG1_ENDREC) == 0);
/* Calculate the offsets of the next and previous blocks */
dev->prvblkpos = dev->nxtblkpos;
dev->nxtblkpos = blkpos;
/* Increment current file number if tapemark was skipped */
if (blklen == 0)
dev->curfilen++;
dev->blockid++;
/* Return block length or zero if tapemark */
return blklen;
} /* end function fsb_awstape */
/*-------------------------------------------------------------------*/
/* Backspace to previous block of AWSTAPE format file */
/* */
/* If successful, return value is the length of the block. */
/* If the block is a tapemark, the return value is zero, */
/* and the current file number in the device block is decremented. */
/* If error, return value is -1 and unitstat is set to CE+DE+UC */
/*-------------------------------------------------------------------*/
int bsb_awstape (DEVBLK *dev, BYTE *unitstat,BYTE code)
{
int rc; /* Return code */
AWSTAPE_BLKHDR awshdr; /* AWSTAPE block header */
U16 curblkl; /* Length of current block */
U16 prvblkl; /* Length of previous block */
off_t blkpos; /* Offset of block header */
/* Unit check if already at start of tape */
if (dev->nxtblkpos == 0)
{
build_senseX(TAPE_BSENSE_LOADPTERR,dev,unitstat,code);
return -1;
}
/* Backspace to previous block position */
blkpos = dev->prvblkpos;
/* Read the 6-byte block header */
rc = readhdr_awstape (dev, blkpos, &awshdr, unitstat,code);
if (rc < 0) return -1;
/* Extract the block lengths from the block header */
curblkl = ((U16)(awshdr.curblkl[1]) << 8)
| awshdr.curblkl[0];
prvblkl = ((U16)(awshdr.prvblkl[1]) << 8)
| awshdr.prvblkl[0];
/* Calculate the offset of the previous block */
dev->prvblkpos = blkpos - sizeof(awshdr) - prvblkl;
dev->nxtblkpos = blkpos;
/* Decrement current file number if backspaced over tapemark */
if (curblkl == 0)
dev->curfilen--;
dev->blockid--;
/* Return block length or zero if tapemark */
return curblkl;
} /* end function bsb_awstape */
/*-------------------------------------------------------------------*/
/* Forward space to next logical file of AWSTAPE format file */
/* */
/* For AWSTAPE files, the forward space file operation is achieved */
/* by forward spacing blocks until positioned just after a tapemark. */
/* */
/* If successful, return value is zero, and the current file number */
/* in the device block is incremented by fsb_awstape. */
/* If error, return value is -1 and unitstat is set to CE+DE+UC */
/*-------------------------------------------------------------------*/
int fsf_awstape (DEVBLK *dev, BYTE *unitstat,BYTE code)
{
int rc; /* Return code */
while (1)
{
/* Forward space over next block */
rc = fsb_awstape (dev, unitstat,code);
if (rc < 0) return -1;
/* Exit loop if spaced over a tapemark */
if (rc == 0) break;
} /* end while */
/* Return normal status */
return 0;
} /* end function fsf_awstape */
/*-------------------------------------------------------------------*/
/* Backspace to previous logical file of AWSTAPE format file */
/* */
/* For AWSTAPE files, the backspace file operation is achieved */
/* by backspacing blocks until positioned just before a tapemark */
/* or until positioned at start of tape. */
/* */
/* If successful, return value is zero, and the current file number */
/* in the device block is decremented by bsb_awstape. */
/* If error, return value is -1 and unitstat is set to CE+DE+UC */
/*-------------------------------------------------------------------*/
int bsf_awstape (DEVBLK *dev, BYTE *unitstat,BYTE code)
{
int rc; /* Return code */
while (1)
{
/* Exit if now at start of tape */
if (dev->nxtblkpos == 0)
{
build_senseX(TAPE_BSENSE_LOADPTERR,dev,unitstat,code);
return -1;
}
/* Backspace to previous block position */
rc = bsb_awstape (dev, unitstat,code);
if (rc < 0) return -1;
/* Exit loop if backspaced over a tapemark */
if (rc == 0) break;
} /* end while */
/* Return normal status */
return 0;
} /* end function bsf_awstape */
/*********************************************************************/
/* END OF ORIGINAL RB AWS FUNCTIONS */
/*********************************************************************/