diff options
Diffstat (limited to 'lib/sh/fpurge.c')
| -rw-r--r-- | lib/sh/fpurge.c | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/lib/sh/fpurge.c b/lib/sh/fpurge.c new file mode 100644 index 0000000..8cd4e36 --- /dev/null +++ b/lib/sh/fpurge.c @@ -0,0 +1,232 @@ +/* fpurge - Flushing buffers of a FILE stream. */ + +/* Copyright (C) 2007-2020 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 PARAMS((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 +} |