1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 /* Copyright (c) 1988 AT&T */ 30 /* All Rights Reserved */ 31 32 33 /* 34 * Return file offset. 35 * Coordinates with buffering. 36 */ 37 #pragma weak ftell = _ftell 38 39 #include "synonyms.h" 40 #include "file64.h" 41 #include "mtlib.h" 42 #include <fcntl.h> 43 #include <stdio.h> 44 #include <thread.h> 45 #include <synch.h> 46 #include <errno.h> 47 #include <unistd.h> 48 #include <stddef.h> 49 #include <limits.h> 50 #include <sys/types.h> 51 #include "stdiom.h" 52 53 long 54 ftell(FILE *iop) 55 { 56 ptrdiff_t adjust; 57 off64_t tres; 58 rmutex_t *lk; 59 60 FLOCKFILE(lk, iop); 61 if (iop->_cnt < 0) 62 iop->_cnt = 0; 63 if (iop->_flag & _IOREAD) 64 adjust = (ptrdiff_t)-iop->_cnt; 65 else if (iop->_flag & (_IOWRT | _IORW)) { 66 adjust = 0; 67 if (((iop->_flag & (_IOWRT | _IONBF)) == _IOWRT) && 68 (iop->_base != 0)) 69 adjust = iop->_ptr - iop->_base; 70 else if ((iop->_flag & _IORW) && (iop->_base != 0)) 71 adjust = (ptrdiff_t)-iop->_cnt; 72 } else { 73 errno = EBADF; /* file descriptor refers to no open file */ 74 FUNLOCKFILE(lk); 75 return (EOF); 76 } 77 78 tres = lseek64(FILENO(iop), 0, SEEK_CUR); 79 if (tres >= 0) 80 tres += adjust; 81 82 if (tres > LONG_MAX) { 83 errno = EOVERFLOW; 84 FUNLOCKFILE(lk); 85 return (EOF); 86 } 87 88 FUNLOCKFILE(lk); 89 return ((long)tres); 90 } 91