1 /* @(#)fcons.c 2.20 10/11/06 Copyright 1986, 1995-2010 J. Schilling */
2 /*
3 * Copyright (c) 1986, 1995-2010 J. Schilling
4 */
5 /*
6 * The contents of this file are subject to the terms of the
7 * Common Development and Distribution License, Version 1.0 only
8 * (the "License"). You may not use this file except in compliance
9 * with the License.
10 *
11 * See the file CDDL.Schily.txt in this distribution for details.
12 * A copy of the CDDL is also available via the Internet at
13 * http://www.opensource.org/licenses/cddl1.txt
14 *
15 * When distributing Covered Code, include this CDDL HEADER in each
16 * file and include the License file CDDL.Schily.txt from this distribution.
17 */
18
19 #include "schilyio.h"
20
21 /*
22 * Note that because of a definition in schilyio.h we are using
23 * fseeko()/ftello() instead of fseek()/ftell() if available.
24 */
25
26 LOCAL char *fmtab[] = {
27 "", /* 0 FI_NONE */
28 "r", /* 1 FI_READ */
29 "w", /* 2 FI_WRITE **1) */
30 "r+", /* 3 FI_READ | FI_WRITE */
31 "b", /* 4 FI_NONE | FI_BINARY */
32 "rb", /* 5 FI_READ | FI_BINARY */
33 "wb", /* 6 FI_WRITE | FI_BINARY **1) */
34 "r+b", /* 7 FI_READ | FI_WRITE | FI_BINARY */
35
36 /* + FI_APPEND */ "", /* 0 FI_NONE */
37 /* ... */ "r", /* 1 FI_READ */
38 "a", /* 2 FI_WRITE **1) */
39 "a+", /* 3 FI_READ | FI_WRITE */
40 "b", /* 4 FI_NONE | FI_BINARY */
41 "rb", /* 5 FI_READ | FI_BINARY */
42 "ab", /* 6 FI_WRITE | FI_BINARY **1) */
43 "a+b", /* 7 FI_READ | FI_WRITE | FI_BINARY */
44 };
45 /*
46 * NOTES:
47 * 1) fdopen() guarantees not to create/trunc files in this case
48 *
49 * "w" will create/trunc files with fopen()
50 * "a" will create files with fopen()
51 */
52
53
54 EXPORT FILE *
_fcons(fd,f,flag)55 _fcons(fd, f, flag)
56 register FILE *fd;
57 int f;
58 int flag;
59 {
60 int my_gflag = _io_glflag;
61
62 if (fd == (FILE *)NULL)
63 fd = fdopen(f,
64 fmtab[flag&(FI_READ|FI_WRITE|FI_BINARY | FI_APPEND)]);
65
66 if (fd != (FILE *)NULL) {
67 if (flag & FI_APPEND) {
68 (void) fseek(fd, (off_t)0, SEEK_END);
69 }
70 if (flag & FI_UNBUF) {
71 setbuf(fd, NULL);
72 my_gflag |= _JS_IOUNBUF;
73 }
74 set_my_flag(fd, my_gflag); /* must clear it if fd is reused */
75 return (fd);
76 }
77 if (flag & FI_CLOSE)
78 close(f);
79
80 return ((FILE *)NULL);
81 }
82