HCoop / bpt / guile.git / blame
| Commit | Line | Data |
|---|---|---|
| 3d458a81 AW |
1 | /* An ftello() function that works around platform bugs. |
| 2 | Copyright (C) 2007, 2009-2011 Free Software Foundation, Inc. | |
| 3 | ||
| 4 | This program is free software: you can redistribute it and/or modify | |
| 5 | it under the terms of the GNU Lesser General Public License as published by | |
| 6 | the Free Software Foundation; either version 3 of the License, or | |
| 7 | (at your option) any later version. | |
| 8 | ||
| 9 | This program is distributed in the hope that it will be useful, | |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 12 | GNU Lesser General Public License for more details. | |
| 13 | ||
| 14 | You should have received a copy of the GNU Lesser General Public License | |
| 15 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ | |
| 16 | ||
| 17 | #include <config.h> | |
| 18 | ||
| 19 | /* Specification. */ | |
| 20 | #include <stdio.h> | |
| 21 | ||
| 22 | /* Get lseek. */ | |
| 23 | #include <unistd.h> | |
| 24 | ||
| 25 | #include "stdio-impl.h" | |
| 26 | ||
| 27 | off_t | |
| 28 | ftello (FILE *fp) | |
| 29 | #undef ftello | |
| 30 | #if !HAVE_FTELLO | |
| 31 | # undef ftell | |
| 32 | # define ftello ftell | |
| 33 | #endif | |
| 34 | { | |
| 35 | #if LSEEK_PIPE_BROKEN | |
| 36 | /* mingw gives bogus answers rather than failure on non-seekable files. */ | |
| 37 | if (lseek (fileno (fp), 0, SEEK_CUR) == -1) | |
| 38 | return -1; | |
| 39 | #endif | |
| 40 | ||
| 41 | #if FTELLO_BROKEN_AFTER_SWITCHING_FROM_READ_TO_WRITE /* Solaris */ | |
| 42 | /* The Solaris stdio leaves the _IOREAD flag set after reading from a file | |
| 43 | reaches EOF and the program then starts writing to the file. ftello | |
| 44 | gets confused by this. */ | |
| 45 | if (fp_->_flag & _IOWRT) | |
| 46 | { | |
| 47 | off_t pos; | |
| 48 | ||
| 49 | /* Call ftello nevertheless, for the side effects that it does on fp. */ | |
| 50 | ftello (fp); | |
| 51 | ||
| 52 | /* Compute the file position ourselves. */ | |
| 53 | pos = lseek (fileno (fp), (off_t) 0, SEEK_CUR); | |
| 54 | if (pos >= 0) | |
| 55 | { | |
| 56 | if ((fp_->_flag & _IONBF) == 0 && fp_->_base != NULL) | |
| 57 | pos += fp_->_ptr - fp_->_base; | |
| 58 | } | |
| 59 | return pos; | |
| 60 | } | |
| 61 | #endif | |
| 62 | ||
| 63 | #if defined __SL64 && defined __SCLE /* Cygwin */ | |
| 64 | if ((fp->_flags & __SL64) == 0) | |
| 65 | { | |
| 66 | /* Cygwin 1.5.0 through 1.5.24 failed to open stdin in 64-bit | |
| 67 | mode; but has an ftello that requires 64-bit mode. */ | |
| 68 | FILE *tmp = fopen ("/dev/null", "r"); | |
| 69 | if (!tmp) | |
| 70 | return -1; | |
| 71 | fp->_flags |= __SL64; | |
| 72 | fp->_seek64 = tmp->_seek64; | |
| 73 | fclose (tmp); | |
| 74 | } | |
| 75 | #endif | |
| 76 | return ftello (fp); | |
| 77 | } |