Mercurial > hg > octave-jordi > gnulib-hg

annotate lib/freadahead.c @ 10780:5c7a68d31801

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Add support for Haiku.
author Bruno Haible <bruno@clisp.org>
date Mon, 10 Nov 2008 12:37:32 +0100
parents 4611578c5669
children d4475bf2a2bf
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
9158
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
1 /* Retrieve information about a FILE stream.
9780
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
2 Copyright (C) 2007-2008 Free Software Foundation, Inc.
9158
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
3
9309
bbbbbf4cd1c5 Change copyright notice from GPLv2+ to GPLv3+.
Bruno Haible <bruno@clisp.org>
parents: 9280
diff changeset
4 This program is free software: you can redistribute it and/or modify
9158
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
5 it under the terms of the GNU General Public License as published by
9309
bbbbbf4cd1c5 Change copyright notice from GPLv2+ to GPLv3+.
Bruno Haible <bruno@clisp.org>
parents: 9280
diff changeset
6 the Free Software Foundation; either version 3 of the License, or
bbbbbf4cd1c5 Change copyright notice from GPLv2+ to GPLv3+.
Bruno Haible <bruno@clisp.org>
parents: 9280
diff changeset
7 (at your option) any later version.
9158
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
8
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
9 This program is distributed in the hope that it will be useful,
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
12 GNU General Public License for more details.
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
13
9309
bbbbbf4cd1c5 Change copyright notice from GPLv2+ to GPLv3+.
Bruno Haible <bruno@clisp.org>
parents: 9280
diff changeset
14 You should have received a copy of the GNU General Public License
bbbbbf4cd1c5 Change copyright notice from GPLv2+ to GPLv3+.
Bruno Haible <bruno@clisp.org>
parents: 9280
diff changeset
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */
9158
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
16
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
17 #include <config.h>
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
18
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
19 /* Specification. */
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
20 #include "freadahead.h"
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
21
10404
4611578c5669 Add conditional code for SLOW_BUT_NO_HACKS.
Bruno Haible <bruno@clisp.org>
parents: 10140
diff changeset
22 #include <stdlib.h>
9980
2c1ba629f5d5 New private include file lib/stdio-impl.h.
Bruno Haible <bruno@clisp.org>
parents: 9978
diff changeset
23 #include "stdio-impl.h"
2c1ba629f5d5 New private include file lib/stdio-impl.h.
Bruno Haible <bruno@clisp.org>
parents: 9978
diff changeset
24
9158
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
25 size_t
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
26 freadahead (FILE *fp)
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
27 {
10780
5c7a68d31801 Add support for Haiku.
Bruno Haible <bruno@clisp.org>
parents: 10404
diff changeset
28 #if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
9158
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
29 if (fp->_IO_write_ptr > fp->_IO_write_base)
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
30 return 0;
9780
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
31 return (fp->_IO_read_end - fp->_IO_read_ptr)
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
32 + (fp->_flags & _IO_IN_BACKUP ? fp->_IO_save_end - fp->_IO_save_base :
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
33 0);
9981
e3d6988a9347 Add tentative support for DragonFly BSD.
Bruno Haible <bruno@clisp.org>
parents: 9980
diff changeset
34 #elif defined __sferror || defined __DragonFly__ /* FreeBSD, NetBSD, OpenBSD, DragonFly, MacOS X, Cygwin */
e3d6988a9347 Add tentative support for DragonFly BSD.
Bruno Haible <bruno@clisp.org>
parents: 9980
diff changeset
35 if ((fp_->_flags & __SWR) != 0 || fp_->_r < 0)
9158
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
36 return 0;
10140
879d77289ca0 Use special-purpose function in DragonFly BSD.
Bruno Haible <bruno@clisp.org>
parents: 9981
diff changeset
37 # if defined __DragonFly__
879d77289ca0 Use special-purpose function in DragonFly BSD.
Bruno Haible <bruno@clisp.org>
parents: 9981
diff changeset
38 return __sreadahead (fp);
879d77289ca0 Use special-purpose function in DragonFly BSD.
Bruno Haible <bruno@clisp.org>
parents: 9981
diff changeset
39 # else
9981
e3d6988a9347 Add tentative support for DragonFly BSD.
Bruno Haible <bruno@clisp.org>
parents: 9980
diff changeset
40 return fp_->_r
e3d6988a9347 Add tentative support for DragonFly BSD.
Bruno Haible <bruno@clisp.org>
parents: 9980
diff changeset
41 + (HASUB (fp) ? fp_->_ur : 0);
10140
879d77289ca0 Use special-purpose function in DragonFly BSD.
Bruno Haible <bruno@clisp.org>
parents: 9981
diff changeset
42 # endif
9881
e21211210418 Port the extended stdio functions to emx+gcc.
Bruno Haible <bruno@clisp.org>
parents: 9876
diff changeset
43 #elif defined __EMX__ /* emx+gcc */
e21211210418 Port the extended stdio functions to emx+gcc.
Bruno Haible <bruno@clisp.org>
parents: 9876
diff changeset
44 if ((fp->_flags & _IOWRT) != 0)
e21211210418 Port the extended stdio functions to emx+gcc.
Bruno Haible <bruno@clisp.org>
parents: 9876
diff changeset
45 return 0;
e21211210418 Port the extended stdio functions to emx+gcc.
Bruno Haible <bruno@clisp.org>
parents: 9876
diff changeset
46 /* Note: fp->_ungetc_count > 0 implies fp->_rcount <= 0,
e21211210418 Port the extended stdio functions to emx+gcc.
Bruno Haible <bruno@clisp.org>
parents: 9876
diff changeset
47 fp->_ungetc_count = 0 implies fp->_rcount >= 0. */
e21211210418 Port the extended stdio functions to emx+gcc.
Bruno Haible <bruno@clisp.org>
parents: 9876
diff changeset
48 /* equivalent to
e21211210418 Port the extended stdio functions to emx+gcc.
Bruno Haible <bruno@clisp.org>
parents: 9876
diff changeset
49 (fp->_ungetc_count == 0 ? fp->_rcount : fp->_ungetc_count - fp->_rcount) */
e21211210418 Port the extended stdio functions to emx+gcc.
Bruno Haible <bruno@clisp.org>
parents: 9876
diff changeset
50 return (fp->_rcount > 0 ? fp->_rcount : fp->_ungetc_count - fp->_rcount);
9876
057a5220dfd5 Add tentative support for OpenServer.
Bruno Haible <bruno@clisp.org>
parents: 9780
diff changeset
51 #elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw */
9158
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
52 if ((fp_->_flag & _IOWRT) != 0)
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
53 return 0;
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
54 return fp_->_cnt;
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
55 #elif defined __UCLIBC__ /* uClibc */
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
56 # ifdef __STDIO_BUFFERS
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
57 if (fp->__modeflags & __FLAG_WRITING)
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
58 return 0;
9780
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
59 return (fp->__bufread - fp->__bufpos)
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
60 + (fp->__modeflags & __FLAG_UNGOT ? 1 : 0);
9158
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
61 # else
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
62 return 0;
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
63 # endif
9280
a1f6fe4c68c1 Add support for QNX (untested).
Bruno Haible <bruno@clisp.org>
parents: 9158
diff changeset
64 #elif defined __QNX__ /* QNX */
9456
b3c8ee11ddfa Fix port to QNX.
Bruno Haible <bruno@clisp.org>
parents: 9309
diff changeset
65 if ((fp->_Mode & 0x2000 /* _MWRITE */) != 0)
9280
a1f6fe4c68c1 Add support for QNX (untested).
Bruno Haible <bruno@clisp.org>
parents: 9158
diff changeset
66 return 0;
9780
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
67 /* fp->_Buf <= fp->_Next <= fp->_Rend,
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
68 and fp->_Rend may be overridden by fp->_Rsave. */
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
69 return ((fp->_Rsave ? fp->_Rsave : fp->_Rend) - fp->_Next)
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
70 + (fp->_Mode & 0x4000 /* _MBYTE */
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
71 ? (fp->_Back + sizeof (fp->_Back)) - fp->_Rback
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
72 : 0);
10404
4611578c5669 Add conditional code for SLOW_BUT_NO_HACKS.
Bruno Haible <bruno@clisp.org>
parents: 10140
diff changeset
73 #elif defined SLOW_BUT_NO_HACKS /* users can define this */
4611578c5669 Add conditional code for SLOW_BUT_NO_HACKS.
Bruno Haible <bruno@clisp.org>
parents: 10140
diff changeset
74 abort ();
4611578c5669 Add conditional code for SLOW_BUT_NO_HACKS.
Bruno Haible <bruno@clisp.org>
parents: 10140
diff changeset
75 return 0;
9158
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
76 #else
9780
cf325a112b9d Take into account the number of pushed-back bytes (ungetc).
Bruno Haible <bruno@clisp.org>
parents: 9456
diff changeset
77 #error "Please port gnulib freadahead.c to your platform! Look at the definition of fflush, fread, ungetc on your system, then report this to bug-gnulib."
9158
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
78 #endif
d45f26a2b8ff New module 'freadahead'.
Bruno Haible <bruno@clisp.org>
parents:
diff changeset
79 }