Rev 2 | Details | Compare with Previous | Last modification | View Log | RSS feed
Rev | Author | Line No. | Line |
---|---|---|---|
2 | pj | 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. All advertising materials mentioning features or use of this software |
||
17 | * must display the following acknowledgement: |
||
18 | * This product includes software developed by the University of |
||
19 | * California, Berkeley and its contributors. |
||
20 | * 4. Neither the name of the University nor the names of its contributors |
||
21 | * may be used to endorse or promote products derived from this software |
||
22 | * without specific prior written permission. |
||
23 | * |
||
24 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
||
25 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
||
26 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||
27 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
||
28 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
||
29 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
||
30 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
||
31 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
||
32 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
||
33 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
||
34 | * SUCH DAMAGE. |
||
35 | */ |
||
36 | |||
37 | #if defined(LIBC_SCCS) && !defined(lint) |
||
38 | #if 0 |
||
39 | static char sccsid[] = "@(#)fgets.c 8.2 (Berkeley) 12/22/93"; |
||
40 | #endif |
||
41 | static const char rcsid[] = |
||
42 | "$\Id: fgets.c,v 1.5 1996/06/22 10:33:10 jraynard Exp $"; |
||
43 | #endif /* LIBC_SCCS and not lint */ |
||
44 | |||
45 | #include <stdio.h> |
||
46 | #include <string.h> |
||
47 | #include "local.h" |
||
48 | #ifdef _THREAD_SAFE |
||
49 | #include <pthread.h> |
||
50 | #include "pthread_private.h" |
||
51 | #endif |
||
52 | |||
53 | /* |
||
54 | * Read at most n-1 characters from the given file. |
||
55 | * Stop when a newline has been read, or the count runs out. |
||
56 | * Return first argument, or NULL if no characters were read. |
||
57 | */ |
||
58 | char * |
||
59 | fgets(buf, n, fp) |
||
60 | char *buf; |
||
61 | register int n; |
||
62 | register FILE *fp; |
||
63 | { |
||
64 | register size_t len; |
||
65 | register char *s; |
||
66 | register unsigned char *p, *t; |
||
67 | |||
68 | if (n <= 0) /* sanity check */ |
||
69 | return (NULL); |
||
70 | |||
71 | #ifdef _THREAD_SAFE |
||
72 | _thread_flockfile(fp,__FILE__,__LINE__); |
||
73 | #endif |
||
74 | s = buf; |
||
75 | n--; /* leave space for NUL */ |
||
76 | while (n != 0) { |
||
77 | /* |
||
78 | * If the buffer is empty, refill it. |
||
79 | */ |
||
80 | if ((len = fp->_r) <= 0) { |
||
81 | if (__srefill(fp)) { |
||
82 | /* EOF/error: stop with partial or no line */ |
||
83 | if (s == buf) { |
||
84 | #ifdef _THREAD_SAFE |
||
85 | _thread_funlockfile(fp); |
||
86 | #endif |
||
87 | return (NULL); |
||
88 | } |
||
89 | break; |
||
90 | } |
||
91 | len = fp->_r; |
||
92 | } |
||
93 | p = fp->_p; |
||
94 | |||
95 | /* |
||
96 | * Scan through at most n bytes of the current buffer, |
||
97 | * looking for '\n'. If found, copy up to and including |
||
98 | * newline, and stop. Otherwise, copy entire chunk |
||
99 | * and loop. |
||
100 | */ |
||
101 | if (len > n) |
||
102 | len = n; |
||
103 | t = memchr((void *)p, '\n', len); |
||
104 | if (t != NULL) { |
||
105 | len = ++t - p; |
||
106 | fp->_r -= len; |
||
107 | fp->_p = t; |
||
108 | (void)memcpy((void *)s, (void *)p, len); |
||
109 | s[len] = 0; |
||
110 | #ifdef _THREAD_SAFE |
||
111 | _thread_funlockfile(fp); |
||
112 | #endif |
||
113 | return (buf); |
||
114 | } |
||
115 | fp->_r -= len; |
||
116 | fp->_p += len; |
||
117 | (void)memcpy((void *)s, (void *)p, len); |
||
118 | s += len; |
||
119 | n -= len; |
||
120 | } |
||
121 | *s = 0; |
||
122 | #ifdef _THREAD_SAFE |
||
123 | _thread_funlockfile(fp); |
||
124 | #endif |
||
125 | return (buf); |
||
126 | } |