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/********************************************************************
* this file has debug versions of segment_get() and segment_put()
* which check the row,col and print error messages to stderr upon
* violations
*
* No functional change, just additional overhead to check the row,col.
*
* load the debug.o file before the SEGMENTLIB and the debug versions
* will supercede the original.
******************************************************************/
#include <stdio.h>
#include "segment.h"
static int check(SEGMENT *,int,int,char *);
/*!
* \brief get value from segment file
*
* Provides random read access to the segmented data. It gets
* <i>len</i> bytes of data into <b>value</b> from the segment file
* <b>seg</b> for the corresponding <b>row</b> and <b>col</b> in the
* original data matrix.
* Return codes are: 1 if ok; else -1 could not seek or read segment file.
*
* \param seg
* \param value
* \param row
* \param col
* \return int
*/
int segment_get (SEGMENT *SEG,void *buf,int row,int col)
{
int n;
int index;
int i;
char *b, *p=buf;
if (!check(SEG, row, col, "segment_get"))
return -1;
segment_address (SEG, row, col, &n, &index);
if((i = segment_pagein (SEG, n)) < 0)
return -1;
b = &SEG->scb[i].buf[index];
n = SEG->len;
while (n-- > 0)
*p++ = *b++;
return 1;
}
/*!
* \brief put value to segment file
*
* Provides random write access to the segmented data. It
* copies <i>len</i> bytes of data from <b>value</b> into the segment
* structure <b>seg</b> for the corresponding <b>row</b> and <b>col</b> in
* the original data matrix.
* The data is not written to disk immediately. It is stored in a memory segment
* until the segment routines decide to page the segment to disk.
* Return codes are: 1 if ok; else -1 could not seek or write segment file.
*
* \param seg
* \param value
* \param row
* \param col
* \return int
*/
int segment_put (SEGMENT *SEG,void *buf,int row,int col)
{
int n;
int index;
int i;
char *b, *p = buf;
if (!check(SEG, row, col, "segment_put"))
return -1;
segment_address (SEG, row, col, &n, &index);
if((i = segment_pagein (SEG, n)) < 0)
return -1;
b = &SEG->scb[i].buf[index];
SEG->scb[i].dirty = 1;
n = SEG->len;
while (n-- > 0)
*b++ = *p++;
return 1;
}
static int check(SEGMENT *SEG,int row,int col,char *me)
{
int r,c;
r = row >= 0 && row < SEG->nrows;
c = col >= 0 && col < SEG->ncols;
if (r && c) return 1;
fprintf (stderr, "%s(SEG=%lx,fd=%d,row=%d,col=%d) ",
me, (long int)SEG, SEG->fd, row, col);
if (!r)
{
fprintf (stderr, "bad row ");
if (row >= SEG->nrows)
fprintf (stderr, "(max %d) ", SEG->nrows-1);
}
if (!c)
{
fprintf (stderr, "bad col ");
if (col >= SEG->ncols)
fprintf (stderr, "(max %d) ", SEG->ncols-1);
}
fprintf (stderr, "\n");
return 0;
}
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