Annotation of prex/usr/lib/libc/stdio/putc.c, Revision 1.1.1.1
1.1 nbrk 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:
33: #include <stdio.h>
34: #include "local.h"
35:
36: /*
37: * Write the given character into the (probably full) buffer for
38: * the given file. Flush the buffer out if it is or becomes full,
39: * or if c=='\n' and the file is line buffered.
40: */
41: int
42: __swbuf(c, fp)
43: int c;
44: FILE *fp;
45: {
46: int n;
47:
48: if (cantwrite(fp))
49: return (EOF);
50: c = (unsigned char)c;
51:
52: /*
53: * If it is completely full, flush it out. Then, in any case,
54: * stuff c into the buffer. If this causes the buffer to fill
55: * completely, or if c is '\n' and the file is line buffered,
56: * flush it (perhaps a second time). The second flush will always
57: * happen on unbuffered streams, where _bf._size==1; fflush()
58: * guarantees that putc() will always call wbuf() by setting _w
59: * to 0, so we need not do anything else.
60: */
61: n = fp->_p - fp->_bf._base;
62: if (n >= fp->_bf._size) {
63: if (fflush(fp))
64: return (EOF);
65: n = 0;
66: }
67: fp->_w--;
68: *fp->_p++ = c;
69: if (++n == fp->_bf._size || (fp->_flags & __SLBF && c == '\n'))
70: if (fflush(fp))
71: return (EOF);
72: return (c);
73: }
74:
75: int
76: putc(c, fp)
77: int c;
78: FILE *fp;
79: {
80: if (--fp->_w >= 0)
81: return (*fp->_p++ = c);
82: else
83: return (__swbuf(c, fp));
84: }
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