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2aa62f2b | 1 | /** @file\r |
2 | Implementation of ftell as declared in <stdio.h>.\r | |
3 | \r | |
4 | Copyright (c) 2010, Intel Corporation. All rights reserved.<BR>\r | |
5 | This program and the accompanying materials are licensed and made available\r | |
6 | under the terms and conditions of the BSD License that accompanies this\r | |
7 | distribution. The full text of the license may be found at\r | |
8 | http://opensource.org/licenses/bsd-license.php.\r | |
9 | \r | |
10 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
11 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
12 | \r | |
13 | Copyright (c) 1990, 1993\r | |
14 | The Regents of the University of California. All rights reserved.\r | |
15 | \r | |
16 | This code is derived from software contributed to Berkeley by\r | |
17 | Chris Torek.\r | |
18 | \r | |
19 | Redistribution and use in source and binary forms, with or without\r | |
20 | modification, are permitted provided that the following conditions\r | |
21 | are met:\r | |
22 | - Redistributions of source code must retain the above copyright\r | |
23 | notice, this list of conditions and the following disclaimer.\r | |
24 | - Redistributions in binary form must reproduce the above copyright\r | |
25 | notice, this list of conditions and the following disclaimer in the\r | |
26 | documentation and/or other materials provided with the distribution.\r | |
27 | - Neither the name of the University nor the names of its contributors\r | |
28 | may be used to endorse or promote products derived from this software\r | |
29 | without specific prior written permission.\r | |
30 | \r | |
31 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"\r | |
32 | AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE\r | |
33 | IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE\r | |
34 | ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE\r | |
35 | LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR\r | |
36 | CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF\r | |
37 | SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS\r | |
38 | INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN\r | |
39 | CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)\r | |
40 | ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE\r | |
41 | POSSIBILITY OF SUCH DAMAGE.\r | |
42 | \r | |
43 | NetBSD: ftell.c,v 1.15 2003/08/07 16:43:25 agc Exp\r | |
44 | ftell.c 8.2 (Berkeley) 5/4/95\r | |
45 | **/\r | |
46 | #include <LibConfig.h>\r | |
47 | \r | |
48 | #include <assert.h>\r | |
49 | #include <errno.h>\r | |
50 | #include <stdio.h>\r | |
51 | #include "reentrant.h"\r | |
52 | #include "local.h"\r | |
53 | \r | |
54 | /*\r | |
55 | * ftell: return current offset.\r | |
56 | */\r | |
57 | long\r | |
58 | ftell(FILE *fp)\r | |
59 | {\r | |
60 | fpos_t pos;\r | |
61 | \r | |
62 | FLOCKFILE(fp);\r | |
63 | \r | |
64 | if (fp->_seek == NULL) {\r | |
65 | FUNLOCKFILE(fp);\r | |
66 | errno = ESPIPE; /* historic practice */\r | |
67 | return (-1L);\r | |
68 | }\r | |
69 | \r | |
70 | /*\r | |
71 | * Find offset of underlying I/O object, then\r | |
72 | * adjust for buffered bytes.\r | |
73 | */\r | |
74 | __sflush(fp); /* may adjust seek offset on append stream */\r | |
75 | if (fp->_flags & __SOFF)\r | |
76 | pos = fp->_offset;\r | |
77 | else {\r | |
78 | pos = (*fp->_seek)(fp->_cookie, (fpos_t)0, SEEK_CUR);\r | |
79 | if (pos == -1L) {\r | |
80 | FUNLOCKFILE(fp);\r | |
81 | return (long)(pos);\r | |
82 | }\r | |
83 | }\r | |
84 | if (fp->_flags & __SRD) {\r | |
85 | /*\r | |
86 | * Reading. Any unread characters (including\r | |
87 | * those from ungetc) cause the position to be\r | |
88 | * smaller than that in the underlying object.\r | |
89 | */\r | |
90 | pos -= fp->_r;\r | |
91 | if (HASUB(fp))\r | |
92 | pos -= fp->_ur;\r | |
93 | } else if (fp->_flags & __SWR && fp->_p != NULL) {\r | |
94 | /*\r | |
95 | * Writing. Any buffered characters cause the\r | |
96 | * position to be greater than that in the\r | |
97 | * underlying object.\r | |
98 | */\r | |
99 | pos += fp->_p - fp->_bf._base;\r | |
100 | }\r | |
101 | FUNLOCKFILE(fp);\r | |
102 | return (long)(pos);\r | |
103 | }\r |