156 lines
3.4 KiB
C
156 lines
3.4 KiB
C
/*
|
|
* Copyright (c) 1990 The Regents of the University of California.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms are permitted
|
|
* provided that the above copyright notice and this paragraph are
|
|
* duplicated in all such forms and that any documentation,
|
|
* advertising materials, and other materials related to such
|
|
* distribution and use acknowledge that the software was developed
|
|
* by the University of California, Berkeley. The name of the
|
|
* University may not be used to endorse or promote products derived
|
|
* from this software without specific prior written permission.
|
|
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
|
|
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
|
*/
|
|
|
|
/*
|
|
FUNCTION
|
|
<<fread>>---read array elements from a file
|
|
|
|
INDEX
|
|
fread
|
|
|
|
ANSI_SYNOPSIS
|
|
#include <stdio.h>
|
|
size_t fread(void *<[buf]>, size_t <[size]>, size_t <[count]>,
|
|
FILE *<[fp]>);
|
|
|
|
TRAD_SYNOPSIS
|
|
#include <stdio.h>
|
|
size_t fread(<[buf]>, <[size]>, <[count]>, <[fp]>)
|
|
char *<[buf]>;
|
|
size_t <[size]>;
|
|
size_t <[count]>;
|
|
FILE *<[fp]>;
|
|
|
|
DESCRIPTION
|
|
<<fread>> attempts to copy, from the file or stream identified by
|
|
<[fp]>, <[count]> elements (each of size <[size]>) into memory,
|
|
starting at <[buf]>. <<fread>> may copy fewer elements than
|
|
<[count]> if an error, or end of file, intervenes.
|
|
|
|
<<fread>> also advances the file position indicator (if any) for
|
|
<[fp]> by the number of @emph{characters} actually read.
|
|
|
|
RETURNS
|
|
The result of <<fread>> is the number of elements it succeeded in
|
|
reading.
|
|
|
|
PORTABILITY
|
|
ANSI C requires <<fread>>.
|
|
|
|
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
|
|
<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include "local.h"
|
|
|
|
#ifdef __SCLE
|
|
static size_t
|
|
_DEFUN (crlf, (fp, buf, count, eof),
|
|
FILE * fp _AND
|
|
char * buf _AND
|
|
size_t count _AND
|
|
int eof)
|
|
{
|
|
int newcount = 0, r;
|
|
char *s, *d, *e;
|
|
|
|
if (count == 0)
|
|
return 0;
|
|
|
|
e = buf + count;
|
|
for (s=d=buf; s<e-1; s++)
|
|
{
|
|
if (*s == '\r' && s[1] == '\n')
|
|
s++;
|
|
*d++ = *s;
|
|
}
|
|
if (s < e)
|
|
{
|
|
if (*s == '\r')
|
|
{
|
|
int c = __sgetc_raw(fp);
|
|
if (c == '\n')
|
|
*s = '\n';
|
|
else
|
|
ungetc(c, fp);
|
|
}
|
|
*d++ = *s++;
|
|
}
|
|
|
|
|
|
while (d < e)
|
|
{
|
|
r = getc(fp);
|
|
if (r == EOF)
|
|
return count - (e-d);
|
|
*d++ = r;
|
|
}
|
|
|
|
return count;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
size_t
|
|
_DEFUN (fread, (buf, size, count, fp),
|
|
_PTR buf _AND
|
|
size_t size _AND
|
|
size_t count _AND
|
|
FILE * fp)
|
|
{
|
|
register size_t resid;
|
|
register char *p;
|
|
register int r;
|
|
size_t total;
|
|
|
|
if ((resid = count * size) == 0)
|
|
return 0;
|
|
if (fp->_r < 0)
|
|
fp->_r = 0;
|
|
total = resid;
|
|
p = buf;
|
|
|
|
while (resid > (r = fp->_r))
|
|
{
|
|
(void) memcpy ((void *) p, (void *) fp->_p, (size_t) r);
|
|
fp->_p += r;
|
|
/* fp->_r = 0 ... done in __srefill */
|
|
p += r;
|
|
resid -= r;
|
|
if (__srefill (fp))
|
|
{
|
|
/* no more input: return partial result */
|
|
#ifdef __SCLE
|
|
if (fp->_flags & __SCLE)
|
|
return crlf(fp, buf, total-resid, 1) / size;
|
|
#endif
|
|
return (total - resid) / size;
|
|
}
|
|
}
|
|
(void) memcpy ((void *) p, (void *) fp->_p, resid);
|
|
fp->_r -= resid;
|
|
fp->_p += resid;
|
|
#ifdef __SCLE
|
|
if (fp->_flags & __SCLE)
|
|
return crlf(fp, buf, total, 0) / size;
|
|
#endif
|
|
return count;
|
|
}
|