usr/src/ucblib/libucb/port/stdio/fopen.c

   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 (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  28 /*        All Rights Reserved   */
  29
  30 /*
  31  * University Copyright- Copyright (c) 1982, 1986, 1988
  32  * The Regents of the University of California
  33  * All Rights Reserved
  34  *
  35  * University Acknowledgment- Portions of this document are derived from
  36  * software developed by the University of California, Berkeley, and its
  37  * contributors.
  38  */
  39
  40 /*LINTLIBRARY*/
  41
  42 #include <sys/types.h>
  43 #include "file64.h"
  44 #include <stdio.h>
  45 #include <sys/fcntl.h>
  46 #include <unistd.h>
  47 #include <sys/file.h>
  48 #include "stdiom.h"
  49
  50 /* Final argument to _endopen depends on build environment */
  51 #define ALWAYS_LARGE_OPEN       1
  52 #define LARGE_OPEN      (_FILE_OFFSET_BITS == 64)
  53
  54 static FILE *
  55 _endopen(const char *file, const char *mode, FILE *iop, int largefile)
  56 {
  57         int     plus, oflag, fd;
  58
  59         if (iop == NULL || file == NULL || file[0] == '\0')
  60                 return (NULL);
  61         plus = (mode[1] == '+');
  62         switch (mode[0]) {
  63         case 'w':
  64                 oflag = (plus ? O_RDWR : O_WRONLY) | O_TRUNC | O_CREAT;
  65                 break;
  66         case 'a':
  67                 oflag = (plus ? O_RDWR : O_WRONLY) | O_CREAT;
  68                 break;
  69         case 'r':
  70                 oflag = plus ? O_RDWR : O_RDONLY;
  71                 break;
  72         default:
  73                 return (NULL);
  74         }
  75
  76         if (largefile) {
  77                 fd = open64(file, oflag, 0666); /* mapped to open() for V9 */
  78         } else {
  79                 fd = open(file, oflag, 0666);
  80         }
  81         if (fd < 0)
  82                 return (NULL);
  83         iop->_cnt = 0;
  84 #ifdef _LP64
  85         iop->_file = fd;
  86 #else
  87         if (fd <= _FILE_FD_MAX) {
  88                 SET_FILE(iop, fd);
  89         } else if (_file_set(iop, fd, mode) != 0) {
  90                 /* errno set in _file_set() */
  91                 (void) close(fd);
  92                 return (NULL);
  93         }
  94 #endif
  95         iop->_flag = plus ? _IORW : (mode[0] == 'r') ? _IOREAD : _IOWRT;
  96         if (mode[0] == 'a')   {
  97                 if ((lseek64(fd, 0L, SEEK_END)) < 0)  {
  98                         (void) close(fd);
  99                         return (NULL);
 100                 }
 101         }
 102         iop->_base = iop->_ptr = NULL;
 103         /*
 104          * Sys5 does not support _bufsiz
 105          *
 106          * iop->_bufsiz = 0;
 107          */
 108         return (iop);
 109 }
 110
 111 FILE *
 112 fopen(const char *file, const char *mode)
 113 {
 114         FILE    *iop;
 115         FILE    *rc;
 116
 117         iop = _findiop();
 118         rc = _endopen(file, mode, iop, LARGE_OPEN);
 119         if (rc == NULL && iop != NULL)
 120                 iop->_flag = 0; /* release iop */
 121         return (rc);
 122 }
 123
 124 /*
 125  * For _LP64, all fopen() calls are 64-bit calls, i.e., open64() system call.
 126  * There should not be fopen64() calls.
 127  * Similar for freopen64().
 128  */
 129 #if !defined(_LP64)
 130 FILE *
 131 fopen64(const char *file, const char *mode)
 132 {
 133         FILE    *iop;
 134         FILE    *rc;
 135
 136         iop = _findiop();
 137         rc = _endopen(file, mode, iop, ALWAYS_LARGE_OPEN);
 138         if (rc == NULL && iop != NULL)
 139                 iop->_flag = 0; /* release iop */
 140         return (rc);
 141 }
 142 #endif
 143
 144 FILE *
 145 freopen(const char *file, const char *mode, FILE *iop)
 146 {
 147         (void) fclose(iop); /* doesn't matter if this fails */
 148         return (_endopen(file, mode, iop, LARGE_OPEN));
 149 }
 150
 151 #if !defined(_LP64)
 152 FILE *
 153 freopen64(const char *file, const char *mode, FILE *iop)
 154 {
 155         (void) fclose(iop); /* doesn't matter if this fails */
 156         return (_endopen(file, mode, iop, ALWAYS_LARGE_OPEN));
 157 }
 158 #endif