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 | * 4. 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 | ␊ |
33 | #if defined(LIBC_SCCS) && !defined(lint)␊ |
34 | static char sccsid[] = "@(#)flags.c␉8.1 (Berkeley) 6/4/93";␊ |
35 | #endif /* LIBC_SCCS and not lint */␊ |
36 | #include <sys/cdefs.h>␊ |
37 | __FBSDID("$FreeBSD: src/lib/libc/stdio/flags.c,v 1.10 2007/01/09 00:28:06 imp Exp $");␊ |
38 | ␊ |
39 | #include <sys/types.h>␊ |
40 | #include <sys/file.h>␊ |
41 | #include <stdio.h>␊ |
42 | #include <errno.h>␊ |
43 | ␊ |
44 | #include "local.h"␊ |
45 | ␊ |
46 | /*␊ |
47 | * Return the (stdio) flags for a given mode. Store the flags␊ |
48 | * to be passed to an _open() syscall through *optr.␊ |
49 | * Return 0 on error.␊ |
50 | */␊ |
51 | int␊ |
52 | __sflags(mode, optr)␊ |
53 | ␉const char *mode;␊ |
54 | ␉int *optr;␊ |
55 | {␊ |
56 | ␉int ret, m, o;␊ |
57 | ␊ |
58 | ␉switch (*mode++) {␊ |
59 | ␊ |
60 | ␉case 'r':␉/* open for reading */␊ |
61 | ␉␉ret = __SRD;␊ |
62 | ␉␉m = O_RDONLY;␊ |
63 | ␉␉o = 0;␊ |
64 | ␉␉break;␊ |
65 | ␊ |
66 | ␉case 'w':␉/* open for writing */␊ |
67 | ␉␉ret = __SWR;␊ |
68 | ␉␉m = O_WRONLY;␊ |
69 | ␉␉o = O_CREAT | O_TRUNC;␊ |
70 | ␉␉break;␊ |
71 | ␊ |
72 | ␉case 'a':␉/* open for appending */␊ |
73 | ␉␉ret = __SWR;␊ |
74 | ␉␉m = O_WRONLY;␊ |
75 | ␉␉o = O_CREAT | O_APPEND;␊ |
76 | ␉␉break;␊ |
77 | ␊ |
78 | ␉default:␉/* illegal mode */␊ |
79 | ␉␉errno = EINVAL;␊ |
80 | ␉␉return (0);␊ |
81 | ␉}␊ |
82 | ␊ |
83 | ␉/* [rwa]\+ or [rwa]b\+ means read and write */␊ |
84 | ␉if (*mode == 'b')␊ |
85 | ␉␉mode++;␊ |
86 | ␉if (*mode == '+') {␊ |
87 | ␉␉ret = __SRW;␊ |
88 | ␉␉m = O_RDWR;␊ |
89 | ␉␉mode++;␊ |
90 | ␉␉if (*mode == 'b')␊ |
91 | ␉␉␉mode++;␊ |
92 | ␉}␊ |
93 | ␉if (*mode == 'x')␊ |
94 | ␉␉o |= O_EXCL;␊ |
95 | ␉*optr = m | o;␊ |
96 | ␉return (ret);␊ |
97 | }␊ |
98 | |