1 /* Retrieve information about a FILE stream. 2 Copyright (C) 2007-2021 Free Software Foundation, Inc. 3 4 This file is free software: you can redistribute it and/or modify 5 it under the terms of the GNU Lesser General Public License as 6 published by the Free Software Foundation; either version 3 of the 7 License, or (at your option) any later version. 8 9 This file 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 <https://www.gnu.org/licenses/>. */ 16 17 #include <config.h> 18 19 /* Specification. */ 20 #include "fwriting.h" 21 22 #include "stdio-impl.h" 23 24 /* This file is not used on systems that have the __fwriting function, 25 namely glibc >= 2.2, Solaris >= 7, UnixWare >= 7.1.4.MP4, Cygwin >= 1.7.34, 26 Android API >= 29, musl libc. */ 27 28 bool 29 fwriting (FILE *fp) /* */ 30 { 31 /* Most systems provide FILE as a struct and the necessary bitmask in 32 <stdio.h>, because they need it for implementing getc() and putc() as 33 fast macros. */ 34 #if defined _IO_EOF_SEEN || defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 35 /* GNU libc, BeOS, Haiku, Linux libc5 */ 36 return (fp->_flags & (_IO_NO_READS | _IO_CURRENTLY_PUTTING)) != 0; 37 #elif defined __sferror || defined __DragonFly__ || defined __ANDROID__ 38 /* FreeBSD, NetBSD, OpenBSD, DragonFly, Mac OS X, Cygwin < 1.7.34, Minix 3, Android */ 39 return (fp_->_flags & __SWR) != 0; 40 #elif defined __EMX__ /* emx+gcc */ 41 return (fp->_flags & _IOWRT) != 0; 42 #elif defined __minix /* Minix */ 43 return (fp->_flags & _IOWRITING) != 0; 44 #elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, UnixWare, mingw, MSVC, NonStop Kernel, OpenVMS */ 45 return (fp_->_flag & _IOWRT) != 0; 46 #elif defined __UCLIBC__ /* uClibc */ 47 return (fp->__modeflags & __FLAG_WRITING) != 0; 48 #elif defined __QNX__ /* QNX */ 49 return ((fp->_Mode & 0x1 /* _MOPENR */) == 0 50 || (fp->_Mode & 0x2000 /* _MWRITE */) != 0); 51 #elif defined __MINT__ /* Atari FreeMiNT */ 52 if (!fp->__mode.__read) 53 return 1; 54 if (!fp->__mode.__write) 55 return 0; 56 # ifdef _IO_CURRENTLY_PUTTING /* Flag added on 2009-02-28 */ 57 return (fp->__flags & _IO_CURRENTLY_PUTTING) != 0; 58 # else 59 return (fp->__buffer < fp->__put_limit /*|| fp->__bufp == fp->__get_limit ??*/); 60 # endif 61 #elif defined EPLAN9 /* Plan9 */ 62 if (fp->state == 0 /* CLOSED */ || fp->state == 3 /* RD */) 63 return 0; 64 return (fp->state == 4 /* WR */ && (fp->bufl == 0 || fp->wp < fp->rp)); 65 #else 66 # error "Please port gnulib fwriting.c to your platform!" 67 #endif 68 }