/* Copyright (C) 2004 Manuel Novoa III <mjn3@codepoet.org> * * GNU Library General Public License (LGPL) version 2 or later. * * Dedicated to Toni. See uClibc/DEDICATION.mjn3 for details. */ #include "_stdio.h" /* Function to handle transition to reading. * Initialize or verify the stream's orientation (even if writeonly). * Check that the stream is readable. * If currently reading, check that we can transition to writing. * C99 requires that we not be reading, but attempting to * auto-transition by commiting the write buffer is a configurable * option. * Returns 0 on success and EOF otherwise. * * Notes: * There are two function signatures, depending on wchar support, * since with no wchar support the orientation is narrow by default. */ #ifdef __UCLIBC_HAS_WCHAR__ int __stdio_trans2r_o(FILE * __restrict stream, int oflag) #else int __stdio_trans2r(FILE * __restrict stream) #endif { __STDIO_STREAM_VALIDATE(stream); assert(!__STDIO_STREAM_IS_READING(stream)); #ifdef __UCLIBC_HAS_WCHAR__ if (!(stream->__modeflags & oflag)) { if (stream->__modeflags & (__FLAG_NARROW|__FLAG_WIDE)) { __UNDEFINED_OR_NONPORTABLE; goto DO_EBADF; } stream->__modeflags |= oflag; } #endif if (stream->__modeflags & __FLAG_WRITEONLY) { #if defined(__UCLIBC_HAS_WCHAR__) || !defined(__UCLIBC_HAS_STDIO_AUTO_RW_TRANSITION__) DO_EBADF: #endif __set_errno(EBADF); #ifdef __UCLIBC_HAS_STDIO_AUTO_RW_TRANSITION__ ERROR: #endif __STDIO_STREAM_SET_ERROR(stream); __STDIO_STREAM_VALIDATE(stream); return EOF; } if (__STDIO_STREAM_IS_WRITING(stream)) { #ifdef __UCLIBC_HAS_STDIO_AUTO_RW_TRANSITION__ if (__STDIO_COMMIT_WRITE_BUFFER(stream)) { /* commit failed! */ goto ERROR; } assert(!__STDIO_STREAM_BUFFER_WUSED(stream)); __STDIO_STREAM_DISABLE_PUTC(stream); __STDIO_STREAM_CLEAR_WRITING(stream); #else /* C99: Output shall not be directly followed by input without an intervening call to the fflush function or to a file positioning function (fseek, fsetpos, or rewind). */ __UNDEFINED_OR_NONPORTABLE; goto DO_EBADF; #endif } __STDIO_STREAM_SET_READING(stream); /* getc macro is enabled when data is read into buffer. */ __STDIO_STREAM_VALIDATE(stream); return 0; }