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📁 ..
📄 Makefile.inc(3.9 KB)
📄 Symbol.map(2.58 KB)
📄 _flock_stub.c(3.65 KB)
📄 asprintf.c(2.34 KB)
📄 clrerr.c(2.13 KB)
📄 dprintf.c(1.68 KB)
📄 fclose.3(4.04 KB)
📄 fclose.c(3.66 KB)
📄 fcloseall.c(1.55 KB)
📄 fdopen.c(3.41 KB)
📄 feof.c(2.14 KB)
📄 ferror.3(3.67 KB)
📄 ferror.c(2.16 KB)
📄 fflush.3(3.67 KB)
📄 fflush.c(4.15 KB)
📄 fgetc.c(2.18 KB)
📄 fgetln.3(4.45 KB)
📄 fgetln.c(4.62 KB)
📄 fgetpos.c(2.07 KB)
📄 fgets.3(3.76 KB)
📄 fgets.c(3.37 KB)
📄 fgetwc.c(3.02 KB)
📄 fgetwln.3(3.49 KB)
📄 fgetwln.c(2.74 KB)
📄 fgetws.3(3.47 KB)
📄 fgetws.c(3.46 KB)
📄 fileno.c(2.16 KB)
📄 findfp.c(6.1 KB)
📄 flags.c(3.1 KB)
📄 floatio.h(2.43 KB)
📄 flockfile.3(3.05 KB)
📄 fmemopen.c(5.74 KB)
📄 fopen.3(7.66 KB)
📄 fopen.c(3.33 KB)
📄 fopencookie.3(3.9 KB)
📄 fopencookie.c(4.04 KB)
📄 fprintf.c(2.52 KB)
📄 fpurge.c(2.41 KB)
📄 fputc.c(2.29 KB)
📄 fputs.3(3.2 KB)
📄 fputs.c(2.63 KB)
📄 fputwc.c(2.52 KB)
📄 fputws.3(2.71 KB)
📄 fputws.c(2.64 KB)
📄 fread.3(3.77 KB)
📄 fread.c(3.53 KB)
📄 freopen.c(7.35 KB)
📄 fscanf.c(2.71 KB)
📄 fseek.3(6.03 KB)
📄 fseek.c(7.46 KB)
📄 fsetpos.c(2.03 KB)
📄 ftell.c(3.78 KB)
📄 funopen.3(4.71 KB)
📄 funopen.c(2.59 KB)
📄 fvwrite.c(5.7 KB)
📄 fvwrite.h(1.96 KB)
📄 fwalk.c(2.48 KB)
📄 fwide.3(2.58 KB)
📄 fwide.c(1.83 KB)
📄 fwprintf.c(2.06 KB)
📄 fwrite.c(3.45 KB)
📄 fwscanf.c(2.04 KB)
📄 getc.3(4.41 KB)
📄 getc.c(2.27 KB)
📄 getchar.c(2.34 KB)
📄 getdelim.c(4.17 KB)
📄 getline.3(3.56 KB)
📄 getline.c(1.6 KB)
📄 gets.c(2.56 KB)
📄 gets_s.c(3.03 KB)
📄 getw.c(1.97 KB)
📄 getwc.3(3.31 KB)
📄 getwc.c(2.01 KB)
📄 getwchar.c(1.93 KB)
📄 glue.h(1.95 KB)
📄 local.h(5.46 KB)
📄 makebuf.c(3.61 KB)
📄 mktemp.3(7.46 KB)
📄 mktemp.c(5.04 KB)
📄 open_memstream.3(4.61 KB)
📄 open_memstream.c(4.79 KB)
📄 open_wmemstream.c(6.34 KB)
📄 perror.c(2.55 KB)
📄 printf-pos.c(17.48 KB)
📄 printf.3(22.15 KB)
📄 printf.c(2.43 KB)
📄 printf_l.3(3.15 KB)
📄 printfcommon.h(7.42 KB)
📄 printflocal.h(3.3 KB)
📄 putc.3(4.1 KB)
📄 putc.c(2.29 KB)
📄 putchar.c(2.36 KB)
📄 puts.c(2.49 KB)
📄 putw.c(2.28 KB)
📄 putwc.3(2.79 KB)
📄 putwc.c(2.09 KB)
📄 putwchar.c(2 KB)
📄 refill.c(4.04 KB)
📄 remove.3(2.52 KB)
📄 remove.c(2.11 KB)
📄 rewind.c(2.26 KB)
📄 rget.c(2.12 KB)
📄 scanf.3(11.79 KB)
📄 scanf.c(2.68 KB)
📄 scanf_l.3(2.7 KB)
📄 setbuf.3(5.54 KB)
📄 setbuf.c(2.02 KB)
📄 setbuffer.c(2.11 KB)
📄 setvbuf.c(4.71 KB)
📄 snprintf.c(3.12 KB)
📄 sprintf.c(2.54 KB)
📄 sscanf.c(2.52 KB)
📄 stdio.3(10.54 KB)
📄 stdio.c(4.27 KB)
📄 swprintf.c(2.09 KB)
📄 swscanf.c(2.07 KB)
📄 tempnam.c(2.86 KB)
📄 tmpfile.c(2.83 KB)
📄 tmpnam.3(6.08 KB)
📄 tmpnam.c(2.27 KB)
📄 ungetc.3(3.19 KB)
📄 ungetc.c(4.5 KB)
📄 ungetwc.3(3.13 KB)
📄 ungetwc.c(2.57 KB)
📄 vasprintf.c(2.52 KB)
📄 vdprintf.c(2.23 KB)
📄 vfprintf.c(26.28 KB)
📄 vfscanf.c(24.59 KB)
📄 vfwprintf.c(27.54 KB)
📄 vfwscanf.c(21.37 KB)
📄 vprintf.c(2.3 KB)
📄 vscanf.c(2.54 KB)
📄 vsnprintf.c(2.91 KB)
📄 vsprintf.c(2.58 KB)
📄 vsscanf.c(2.72 KB)
📄 vswprintf.c(3.32 KB)
📄 vswscanf.c(3.36 KB)
📄 vwprintf.c(1.9 KB)
📄 vwscanf.c(1.9 KB)
📄 wbuf.c(3.25 KB)
📄 wprintf.3(15.62 KB)
📄 wprintf.c(2.02 KB)
📄 wscanf.3(11.31 KB)
📄 wscanf.c(2 KB)
📄 wsetup.c(3.05 KB)
📄 xprintf.c(16.71 KB)
📄 xprintf_errno.c(2.18 KB)
📄 xprintf_float.c(11.33 KB)
📄 xprintf_hexdump.c(2.65 KB)
📄 xprintf_int.c(10.47 KB)
📄 xprintf_quote.c(2.83 KB)
📄 xprintf_str.c(5.04 KB)
📄 xprintf_time.c(3.46 KB)
📄 xprintf_vis.c(2.41 KB)

Editing: fseek.c

/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Chris Torek.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)fseek.c	8.3 (Berkeley) 1/2/94";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include "namespace.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include "un-namespace.h"
#include "local.h"
#include "libc_private.h"

#define	POS_ERR	(-(fpos_t)1)

int
fseek(FILE *fp, long offset, int whence)
{
	int ret;
	int serrno = errno;

/* make sure stdio is set up */
	if (!__sdidinit)
		__sinit();

FLOCKFILE_CANCELSAFE(fp);
	ret = _fseeko(fp, (off_t)offset, whence, 1);
	FUNLOCKFILE_CANCELSAFE();
	if (ret == 0)
		errno = serrno;
	return (ret);
}

int
fseeko(FILE *fp, off_t offset, int whence)
{
	int ret;
	int serrno = errno;

/* make sure stdio is set up */
	if (!__sdidinit)
		__sinit();

FLOCKFILE_CANCELSAFE(fp);
	ret = _fseeko(fp, offset, whence, 0);
	FUNLOCKFILE_CANCELSAFE();
	if (ret == 0)
		errno = serrno;
	return (ret);
}

/*
 * Seek the given file to the given offset.
 * `Whence' must be one of the three SEEK_* macros.
 */
int
_fseeko(FILE *fp, off_t offset, int whence, int ltest)
{
	fpos_t (*seekfn)(void *, fpos_t, int);
	fpos_t target, curoff, ret;
	size_t n;
	struct stat st;
	int havepos;

/*
	 * Have to be able to seek.
	 */
	if ((seekfn = fp->_seek) == NULL) {
		errno = ESPIPE;		/* historic practice */
		return (-1);
	}

/*
	 * Change any SEEK_CUR to SEEK_SET, and check `whence' argument.
	 * After this, whence is either SEEK_SET or SEEK_END.
	 */
	switch (whence) {

case SEEK_CUR:
		/*
		 * In order to seek relative to the current stream offset,
		 * we have to first find the current stream offset via
		 * ftell (see ftell for details).
		 */
		if (_ftello(fp, &curoff))
			return (-1);
		if (curoff < 0) {
			/* Unspecified position because of ungetc() at 0 */
			errno = ESPIPE;
			return (-1);
		}
		if (offset > 0 && curoff > OFF_MAX - offset) {
			errno = EOVERFLOW;
			return (-1);
		}
		offset += curoff;
		if (offset < 0) {
			errno = EINVAL;
			return (-1);
		}
		if (ltest && offset > LONG_MAX) {
			errno = EOVERFLOW;
			return (-1);
		}
		whence = SEEK_SET;
		havepos = 1;
		break;

case SEEK_SET:
		if (offset < 0) {
			errno = EINVAL;
			return (-1);
		}
	case SEEK_END:
		curoff = 0;		/* XXX just to keep gcc quiet */
		havepos = 0;
		break;

default:
		errno = EINVAL;
		return (-1);
	}

/*
	 * Can only optimise if:
	 *	reading (and not reading-and-writing);
	 *	not unbuffered; and
	 *	this is a `regular' Unix file (and hence seekfn==__sseek).
	 * We must check __NBF first, because it is possible to have __NBF
	 * and __SOPT both set.
	 */
	if (fp->_bf._base == NULL)
		__smakebuf(fp);
	if (fp->_flags & (__SWR | __SRW | __SNBF | __SNPT))
		goto dumb;
	if ((fp->_flags & __SOPT) == 0) {
		if (seekfn != __sseek ||
		    fp->_file < 0 || _fstat(fp->_file, &st) ||
		    (st.st_mode & S_IFMT) != S_IFREG) {
			fp->_flags |= __SNPT;
			goto dumb;
		}
		fp->_blksize = st.st_blksize;
		fp->_flags |= __SOPT;
	}

/*
	 * We are reading; we can try to optimise.
	 * Figure out where we are going and where we are now.
	 */
	if (whence == SEEK_SET)
		target = offset;
	else {
		if (_fstat(fp->_file, &st))
			goto dumb;
		if (offset > 0 && st.st_size > OFF_MAX - offset) {
			errno = EOVERFLOW;
			return (-1);
		}
		target = st.st_size + offset;
		if ((off_t)target < 0) {
			errno = EINVAL;
			return (-1);
		}
		if (ltest && (off_t)target > LONG_MAX) {
			errno = EOVERFLOW;
			return (-1);
		}
	}

if (!havepos && _ftello(fp, &curoff))
		goto dumb;

/*
	 * (If the buffer was modified, we have to
	 * skip this; see fgetln.c.)
	 */
	if (fp->_flags & __SMOD)
		goto abspos;

/*
	 * Compute the number of bytes in the input buffer (pretending
	 * that any ungetc() input has been discarded).  Adjust current
	 * offset backwards by this count so that it represents the
	 * file offset for the first byte in the current input buffer.
	 */
	if (HASUB(fp)) {
		curoff += fp->_r;	/* kill off ungetc */
		n = fp->_up - fp->_bf._base;
		curoff -= n;
		n += fp->_ur;
	} else {
		n = fp->_p - fp->_bf._base;
		curoff -= n;
		n += fp->_r;
	}

/*
	 * If the target offset is within the current buffer,
	 * simply adjust the pointers, clear EOF, undo ungetc(),
	 * and return.
	 */
	if (target >= curoff && target < curoff + n) {
		size_t o = target - curoff;

fp->_p = fp->_bf._base + o;
		fp->_r = n - o;
		if (HASUB(fp))
			FREEUB(fp);
		fp->_flags &= ~__SEOF;
		memset(&fp->_mbstate, 0, sizeof(mbstate_t));
		return (0);
	}

abspos:
	/*
	 * The place we want to get to is not within the current buffer,
	 * but we can still be kind to the kernel copyout mechanism.
	 * By aligning the file offset to a block boundary, we can let
	 * the kernel use the VM hardware to map pages instead of
	 * copying bytes laboriously.  Using a block boundary also
	 * ensures that we only read one block, rather than two.
	 */
	curoff = target & ~(fp->_blksize - 1);
	if (_sseek(fp, curoff, SEEK_SET) == POS_ERR)
		goto dumb;
	fp->_r = 0;
	fp->_p = fp->_bf._base;
	if (HASUB(fp))
		FREEUB(fp);
	n = target - curoff;
	if (n) {
		if (__srefill(fp) || fp->_r < n)
			goto dumb;
		fp->_p += n;
		fp->_r -= n;
	}
	fp->_flags &= ~__SEOF;
	memset(&fp->_mbstate, 0, sizeof(mbstate_t));
	return (0);

/*
	 * We get here if we cannot optimise the seek ... just
	 * do it.  Allow the seek function to change fp->_bf._base.
	 */
dumb:
	if (__sflush(fp) ||
	    (ret = _sseek(fp, (fpos_t)offset, whence)) == POS_ERR)
		return (-1);
	if (ltest && ret > LONG_MAX) {
		fp->_flags |= __SERR;
		errno = EOVERFLOW;
		return (-1);
	}
	/* success: clear EOF indicator and discard ungetc() data */
	if (HASUB(fp))
		FREEUB(fp);
	fp->_p = fp->_bf._base;
	fp->_r = 0;
	/* fp->_w = 0; */	/* unnecessary (I think...) */
	fp->_flags &= ~__SEOF;
	memset(&fp->_mbstate, 0, sizeof(mbstate_t));
	return (0);
}

003 File Manager

Editing: fseek.c

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