| /* fpurge - Flushing buffers of a FILE stream. */ |
| |
| /* Copyright (C) 2007-2010 Free Software Foundation, Inc. |
| |
| This file is part of GNU Bash, the Bourne Again SHell. |
| |
| Bash is free software: you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation, either version 3 of the License, or |
| (at your option) any later version. |
| |
| Bash is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with Bash. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include <config.h> |
| |
| #include "stdc.h" |
| |
| #include <stdio.h> |
| |
| /* Specification. Same as in ../../externs.h. */ |
| #define NEED_FPURGE_DECL |
| #if HAVE_FPURGE |
| # define fpurge _bash_fpurge |
| #endif |
| extern int fpurge __P((FILE *stream)); |
| |
| #if HAVE___FPURGE /* glibc >= 2.2, Haiku, Solaris >= 7 */ |
| # include <stdio_ext.h> |
| #endif |
| #include <stdlib.h> |
| |
| /* Inline contents of gnulib:stdio-impl.h */ |
| |
| /* Many stdio implementations have the same logic and therefore can share |
| the same implementation of stdio extension API, except that some fields |
| have different naming conventions, or their access requires some casts. */ |
| |
| /* BSD stdio derived implementations. */ |
| |
| #if defined __NetBSD__ /* NetBSD */ |
| /* Get __NetBSD_Version__. */ |
| # include <sys/param.h> |
| #endif |
| |
| #if defined __sferror || defined __DragonFly__ /* FreeBSD, NetBSD, OpenBSD, DragonFly, MacOS X, Cygwin */ |
| |
| # if defined __DragonFly__ /* DragonFly */ |
| /* See <http://www.dragonflybsd.org/cvsweb/src/lib/libc/stdio/priv_stdio.h?rev=HEAD&content-type=text/x-cvsweb-markup>. */ |
| # define fp_ ((struct { struct __FILE_public pub; \ |
| struct { unsigned char *_base; int _size; } _bf; \ |
| void *cookie; \ |
| void *_close; \ |
| void *_read; \ |
| void *_seek; \ |
| void *_write; \ |
| struct { unsigned char *_base; int _size; } _ub; \ |
| int _ur; \ |
| unsigned char _ubuf[3]; \ |
| unsigned char _nbuf[1]; \ |
| struct { unsigned char *_base; int _size; } _lb; \ |
| int _blksize; \ |
| fpos_t _offset; \ |
| /* More fields, not relevant here. */ \ |
| } *) fp) |
| /* See <http://www.dragonflybsd.org/cvsweb/src/include/stdio.h?rev=HEAD&content-type=text/x-cvsweb-markup>. */ |
| # define _p pub._p |
| # define _flags pub._flags |
| # define _r pub._r |
| # define _w pub._w |
| # else |
| # define fp_ fp |
| # endif |
| |
| # if (defined __NetBSD__ && __NetBSD_Version__ >= 105270000) || defined __OpenBSD__ /* NetBSD >= 1.5ZA, OpenBSD */ |
| /* See <http://cvsweb.netbsd.org/bsdweb.cgi/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup> |
| and <http://www.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup> */ |
| struct __sfileext |
| { |
| struct __sbuf _ub; /* ungetc buffer */ |
| /* More fields, not relevant here. */ |
| }; |
| # define fp_ub ((struct __sfileext *) fp->_ext._base)->_ub |
| # else /* FreeBSD, NetBSD <= 1.5Z, DragonFly, MacOS X, Cygwin */ |
| # define fp_ub fp_->_ub |
| # endif |
| |
| # define HASUB(fp) (fp_ub._base != NULL) |
| |
| #endif |
| |
| /* SystemV derived implementations. */ |
| |
| #if defined _IOERR |
| |
| # if defined __sun && defined _LP64 /* Solaris/{SPARC,AMD64} 64-bit */ |
| # define fp_ ((struct { unsigned char *_ptr; \ |
| unsigned char *_base; \ |
| unsigned char *_end; \ |
| long _cnt; \ |
| int _file; \ |
| unsigned int _flag; \ |
| } *) fp) |
| # else |
| # define fp_ fp |
| # endif |
| |
| # if defined _SCO_DS /* OpenServer */ |
| # define _cnt __cnt |
| # define _ptr __ptr |
| # define _base __base |
| # define _flag __flag |
| # endif |
| |
| #endif |
| |
| int |
| fpurge (FILE *fp) |
| { |
| #if HAVE___FPURGE /* glibc >= 2.2, Haiku, Solaris >= 7 */ |
| |
| __fpurge (fp); |
| /* The __fpurge function does not have a return value. */ |
| return 0; |
| |
| #elif HAVE_FPURGE /* FreeBSD, NetBSD, OpenBSD, DragonFly, MacOS X, Cygwin 1.7 */ |
| |
| /* Call the system's fpurge function. */ |
| # undef fpurge |
| # if !HAVE_DECL_FPURGE |
| extern int fpurge (FILE *); |
| # endif |
| int result = fpurge (fp); |
| # if defined __sferror || defined __DragonFly__ /* FreeBSD, NetBSD, OpenBSD, DragonFly, MacOS X, Cygwin */ |
| if (result == 0) |
| /* Correct the invariants that fpurge broke. |
| <stdio.h> on BSD systems says: |
| "The following always hold: if _flags & __SRD, _w is 0." |
| If this invariant is not fulfilled and the stream is read-write but |
| currently reading, subsequent putc or fputc calls will write directly |
| into the buffer, although they shouldn't be allowed to. */ |
| if ((fp_->_flags & __SRD) != 0) |
| fp_->_w = 0; |
| # endif |
| return result; |
| |
| #else |
| |
| /* Most systems provide FILE as a struct and the necessary bitmask in |
| <stdio.h>, because they need it for implementing getc() and putc() as |
| fast macros. */ |
| # if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */ |
| fp->_IO_read_end = fp->_IO_read_ptr; |
| fp->_IO_write_ptr = fp->_IO_write_base; |
| /* Avoid memory leak when there is an active ungetc buffer. */ |
| if (fp->_IO_save_base != NULL) |
| { |
| free (fp->_IO_save_base); |
| fp->_IO_save_base = NULL; |
| } |
| return 0; |
| # elif defined __sferror || defined __DragonFly__ /* FreeBSD, NetBSD, OpenBSD, DragonFly, MacOS X, Cygwin */ |
| fp_->_p = fp_->_bf._base; |
| fp_->_r = 0; |
| fp_->_w = ((fp_->_flags & (__SLBF | __SNBF | __SRD)) == 0 /* fully buffered and not currently reading? */ |
| ? fp_->_bf._size |
| : 0); |
| /* Avoid memory leak when there is an active ungetc buffer. */ |
| if (fp_ub._base != NULL) |
| { |
| if (fp_ub._base != fp_->_ubuf) |
| free (fp_ub._base); |
| fp_ub._base = NULL; |
| } |
| return 0; |
| # elif defined __EMX__ /* emx+gcc */ |
| fp->_ptr = fp->_buffer; |
| fp->_rcount = 0; |
| fp->_wcount = 0; |
| fp->_ungetc_count = 0; |
| return 0; |
| # elif defined _IOERR || defined __TANDEM /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw */ |
| fp->_ptr = fp->_base; |
| if (fp->_ptr != NULL) |
| fp->_cnt = 0; |
| return 0; |
| # elif defined __UCLIBC__ /* uClibc */ |
| # ifdef __STDIO_BUFFERS |
| if (fp->__modeflags & __FLAG_WRITING) |
| fp->__bufpos = fp->__bufstart; |
| else if (fp->__modeflags & (__FLAG_READONLY | __FLAG_READING)) |
| fp->__bufpos = fp->__bufread; |
| # endif |
| return 0; |
| # elif defined __QNX__ /* QNX */ |
| fp->_Rback = fp->_Back + sizeof (fp->_Back); |
| fp->_Rsave = NULL; |
| if (fp->_Mode & 0x2000 /* _MWRITE */) |
| /* fp->_Buf <= fp->_Next <= fp->_Wend */ |
| fp->_Next = fp->_Buf; |
| else |
| /* fp->_Buf <= fp->_Next <= fp->_Rend */ |
| fp->_Rend = fp->_Next; |
| return 0; |
| # elif defined __MINT__ /* Atari FreeMiNT */ |
| if (fp->__pushed_back) |
| { |
| fp->__bufp = fp->__pushback_bufp; |
| fp->__pushed_back = 0; |
| } |
| /* Preserve the current file position. */ |
| if (fp->__target != -1) |
| fp->__target += fp->__bufp - fp->__buffer; |
| fp->__bufp = fp->__buffer; |
| /* Nothing in the buffer, next getc is nontrivial. */ |
| fp->__get_limit = fp->__bufp; |
| /* Nothing in the buffer, next putc is nontrivial. */ |
| fp->__put_limit = fp->__buffer; |
| return 0; |
| # else |
| # warning "Please port gnulib fpurge.c to your platform! Look at the definitions of fflush, setvbuf and ungetc on your system, then report this to bug-gnulib." |
| return 0; |
| # endif |
| |
| #endif |
| } |