272 lines
6.8 KiB
C
272 lines
6.8 KiB
C
/*
|
|
* Copyright (c) 1990, 2007 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>>, <<fread_unlocked>>---read array elements from a file
|
|
|
|
INDEX
|
|
fread
|
|
INDEX
|
|
fread_unlocked
|
|
INDEX
|
|
_fread_r
|
|
INDEX
|
|
_fread_unlocked_r
|
|
|
|
SYNOPSIS
|
|
#include <stdio.h>
|
|
size_t fread(void *restrict <[buf]>, size_t <[size]>, size_t <[count]>,
|
|
FILE *restrict <[fp]>);
|
|
|
|
#define _BSD_SOURCE
|
|
#include <stdio.h>
|
|
size_t fread_unlocked(void *restrict <[buf]>, size_t <[size]>, size_t <[count]>,
|
|
FILE *restrict <[fp]>);
|
|
|
|
#include <stdio.h>
|
|
size_t _fread_r(struct _reent *<[ptr]>, void *restrict <[buf]>,
|
|
size_t <[size]>, size_t <[count]>, FILE *restrict <[fp]>);
|
|
|
|
#include <stdio.h>
|
|
size_t _fread_unlocked_r(struct _reent *<[ptr]>, void *restrict <[buf]>,
|
|
size_t <[size]>, size_t <[count]>, FILE *restrict <[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.
|
|
|
|
<<fread_unlocked>> is a non-thread-safe version of <<fread>>.
|
|
<<fread_unlocked>> may only safely be used within a scope
|
|
protected by flockfile() (or ftrylockfile()) and funlockfile(). This
|
|
function may safely be used in a multi-threaded program if and only
|
|
if they are called while the invoking thread owns the (FILE *)
|
|
object, as is the case after a successful call to the flockfile() or
|
|
ftrylockfile() functions. If threads are disabled, then
|
|
<<fread_unlocked>> is equivalent to <<fread>>.
|
|
|
|
<<_fread_r>> and <<_fread_unlocked_r>> are simply reentrant versions of the
|
|
above that take an additional reentrant structure pointer argument: <[ptr]>.
|
|
|
|
RETURNS
|
|
The result of <<fread>> is the number of elements it succeeded in
|
|
reading.
|
|
|
|
PORTABILITY
|
|
ANSI C requires <<fread>>.
|
|
|
|
<<fread_unlocked>> is a BSD extension also provided by GNU libc.
|
|
|
|
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
|
|
<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
|
|
*/
|
|
|
|
#include <_ansi.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <malloc.h>
|
|
#include "local.h"
|
|
|
|
#ifdef __IMPL_UNLOCKED__
|
|
#define _fread_r _fread_unlocked_r
|
|
#define fread fread_unlocked
|
|
#endif
|
|
|
|
#ifdef __SCLE
|
|
static size_t
|
|
_DEFUN(crlf_r, (ptr, fp, buf, count, eof),
|
|
struct _reent * ptr _AND
|
|
FILE * fp _AND
|
|
char * buf _AND
|
|
size_t count _AND
|
|
int eof)
|
|
{
|
|
int 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_r (ptr, fp);
|
|
if (c == '\n')
|
|
*s = '\n';
|
|
else
|
|
ungetc (c, fp);
|
|
}
|
|
*d++ = *s++;
|
|
}
|
|
|
|
|
|
while (d < e)
|
|
{
|
|
r = _getc_r (ptr, fp);
|
|
if (r == EOF)
|
|
return count - (e-d);
|
|
*d++ = r;
|
|
}
|
|
|
|
return count;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
size_t
|
|
_DEFUN(_fread_r, (ptr, buf, size, count, fp),
|
|
struct _reent * ptr _AND
|
|
_PTR __restrict buf _AND
|
|
size_t size _AND
|
|
size_t count _AND
|
|
FILE * __restrict fp)
|
|
{
|
|
register size_t resid;
|
|
register char *p;
|
|
register int r;
|
|
size_t total;
|
|
|
|
if ((resid = count * size) == 0)
|
|
return 0;
|
|
|
|
CHECK_INIT(ptr, fp);
|
|
|
|
_newlib_flockfile_start (fp);
|
|
ORIENT (fp, -1);
|
|
if (fp->_r < 0)
|
|
fp->_r = 0;
|
|
total = resid;
|
|
p = buf;
|
|
|
|
#if !defined(PREFER_SIZE_OVER_SPEED) && !defined(__OPTIMIZE_SIZE__)
|
|
|
|
/* Optimize unbuffered I/O. */
|
|
if (fp->_flags & __SNBF)
|
|
{
|
|
/* First copy any available characters from ungetc buffer. */
|
|
int copy_size = resid > fp->_r ? fp->_r : resid;
|
|
_CAST_VOID memcpy ((_PTR) p, (_PTR) fp->_p, (size_t) copy_size);
|
|
fp->_p += copy_size;
|
|
fp->_r -= copy_size;
|
|
p += copy_size;
|
|
resid -= copy_size;
|
|
|
|
/* If still more data needed, free any allocated ungetc buffer. */
|
|
if (HASUB (fp) && resid > 0)
|
|
FREEUB (ptr, fp);
|
|
|
|
/* Finally read directly into user's buffer if needed. */
|
|
while (resid > 0)
|
|
{
|
|
int rc = 0;
|
|
/* save fp buffering state */
|
|
void *old_base = fp->_bf._base;
|
|
void * old_p = fp->_p;
|
|
int old_size = fp->_bf._size;
|
|
/* allow __refill to use user's buffer */
|
|
fp->_bf._base = (unsigned char *) p;
|
|
fp->_bf._size = resid;
|
|
fp->_p = (unsigned char *) p;
|
|
rc = __srefill_r (ptr, fp);
|
|
/* restore fp buffering back to original state */
|
|
fp->_bf._base = old_base;
|
|
fp->_bf._size = old_size;
|
|
fp->_p = old_p;
|
|
resid -= fp->_r;
|
|
p += fp->_r;
|
|
fp->_r = 0;
|
|
if (rc)
|
|
{
|
|
#ifdef __SCLE
|
|
if (fp->_flags & __SCLE)
|
|
{
|
|
_newlib_flockfile_exit (fp);
|
|
return crlf_r (ptr, fp, buf, total-resid, 1) / size;
|
|
}
|
|
#endif
|
|
_newlib_flockfile_exit (fp);
|
|
return (total - resid) / size;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
#endif /* !PREFER_SIZE_OVER_SPEED && !__OPTIMIZE_SIZE__ */
|
|
{
|
|
while (resid > (r = fp->_r))
|
|
{
|
|
_CAST_VOID memcpy ((_PTR) p, (_PTR) fp->_p, (size_t) r);
|
|
fp->_p += r;
|
|
/* fp->_r = 0 ... done in __srefill */
|
|
p += r;
|
|
resid -= r;
|
|
if (__srefill_r (ptr, fp))
|
|
{
|
|
/* no more input: return partial result */
|
|
#ifdef __SCLE
|
|
if (fp->_flags & __SCLE)
|
|
{
|
|
_newlib_flockfile_exit (fp);
|
|
return crlf_r (ptr, fp, buf, total-resid, 1) / size;
|
|
}
|
|
#endif
|
|
_newlib_flockfile_exit (fp);
|
|
return (total - resid) / size;
|
|
}
|
|
}
|
|
_CAST_VOID memcpy ((_PTR) p, (_PTR) fp->_p, resid);
|
|
fp->_r -= resid;
|
|
fp->_p += resid;
|
|
}
|
|
|
|
/* Perform any CR/LF clean-up if necessary. */
|
|
#ifdef __SCLE
|
|
if (fp->_flags & __SCLE)
|
|
{
|
|
_newlib_flockfile_exit (fp);
|
|
return crlf_r(ptr, fp, buf, total, 0) / size;
|
|
}
|
|
#endif
|
|
_newlib_flockfile_end (fp);
|
|
return count;
|
|
}
|
|
|
|
#ifndef _REENT_ONLY
|
|
size_t
|
|
_DEFUN(fread, (buf, size, count, fp),
|
|
_PTR __restrict buf _AND
|
|
size_t size _AND
|
|
size_t count _AND
|
|
FILE *__restrict fp)
|
|
{
|
|
return _fread_r (_REENT, buf, size, count, fp);
|
|
}
|
|
#endif
|