1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Chris Torek. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)flags.c 8.1 (Berkeley) 6/4/93 33 * $FreeBSD: src/lib/libc/stdio/flags.c,v 1.10 2007/01/09 00:28:06 imp Exp $ 34 */ 35 36 #include <sys/types.h> 37 #include <stdio.h> 38 #include <errno.h> 39 #include <fcntl.h> 40 41 #include "local.h" 42 43 /* 44 * Return the (stdio) flags for a given mode. Store the flags 45 * to be passed to an _open() syscall through *optr. 46 * Return 0 on error. 47 */ 48 int 49 __sflags(const char *mode, int *optr) 50 { 51 int ret, m, o; 52 53 /* 54 * Base mode 55 */ 56 switch (*mode) { 57 case 'r': 58 /* 59 * Reading 60 */ 61 ret = __SRD; 62 m = O_RDONLY; 63 o = 0; 64 break; 65 case 'w': 66 /* 67 * Writing 68 */ 69 ret = __SWR; 70 m = O_WRONLY; 71 o = O_CREAT | O_TRUNC; 72 break; 73 case 'a': 74 /* 75 * Append 76 */ 77 ret = __SWR; 78 m = O_WRONLY; 79 o = O_CREAT | O_APPEND; 80 break; 81 default: 82 /* 83 * Illegal primary mode, fail. 84 */ 85 errno = EINVAL; 86 return (0); 87 } 88 89 /* 90 * Parse modifiers 91 */ 92 for (++mode; *mode; ++mode) { 93 switch(*mode) { 94 case '+': 95 /* 96 * R+W 97 */ 98 ret = __SRW; 99 m = O_RDWR; 100 break; 101 case 'b': 102 /* 103 * Binary (inherent, no special treatment) 104 */ 105 break; 106 case 'x': 107 /* 108 * Exclusive. Only make sense if opening for 109 * r+w, w, or a, but let open() deal with 110 * any issues (make behavior the same as glibc). 111 */ 112 o |= O_EXCL; 113 break; 114 case 'e': 115 o |= O_CLOEXEC; 116 break; 117 default: 118 /* ignore unrecognized flag */ 119 break; 120 } 121 } 122 *optr = m | o; 123 124 return (ret); 125 } 126