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 * $DragonFly: src/lib/libc/stdio/flags.c,v 1.5 2005/01/31 22:29:40 dillon Exp $ 35 */ 36 37 #include <sys/types.h> 38 #include <sys/file.h> 39 #include <stdio.h> 40 #include <errno.h> 41 42 #include "local.h" 43 44 /* 45 * Return the (stdio) flags for a given mode. Store the flags 46 * to be passed to an _open() syscall through *optr. 47 * Return 0 on error. 48 */ 49 int 50 __sflags(const char *mode, int *optr) 51 { 52 int ret, m, o; 53 54 /* 55 * Base mode 56 */ 57 switch (*mode) { 58 case 'r': 59 /* 60 * Reading 61 */ 62 ret = __SRD; 63 m = O_RDONLY; 64 o = 0; 65 break; 66 case 'w': 67 /* 68 * Writing 69 */ 70 ret = __SWR; 71 m = O_WRONLY; 72 o = O_CREAT | O_TRUNC; 73 break; 74 case 'a': 75 /* 76 * Append 77 */ 78 ret = __SWR; 79 m = O_WRONLY; 80 o = O_CREAT | O_APPEND; 81 break; 82 default: 83 /* 84 * Illegal primary mode, fail. 85 */ 86 errno = EINVAL; 87 return (0); 88 } 89 90 /* 91 * Parse modifiers 92 */ 93 for (++mode; *mode; ++mode) { 94 switch(*mode) { 95 case '+': 96 /* 97 * R+W 98 */ 99 ret = __SRW; 100 m = O_RDWR; 101 break; 102 case 'b': 103 /* 104 * Binary (inherent, no special treatment) 105 */ 106 break; 107 case 'x': 108 /* 109 * Exclusive. Only make sense if opening for 110 * r+w, w, or a, but let open() deal with 111 * any issues (make behavior the same as glibc). 112 */ 113 o |= O_EXCL; 114 break; 115 case 'e': 116 o |= O_CLOEXEC; 117 break; 118 default: 119 /* ignore unrecognized flag */ 120 break; 121 } 122 } 123 *optr = m | o; 124 125 return (ret); 126 } 127