diff options
Diffstat (limited to 'libc/stdio/freopen.c')
-rw-r--r-- | libc/stdio/freopen.c | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/libc/stdio/freopen.c b/libc/stdio/freopen.c new file mode 100644 index 000000000..0eccaac1f --- /dev/null +++ b/libc/stdio/freopen.c @@ -0,0 +1,66 @@ +/* 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" + +#ifdef __DO_LARGEFILE +# ifndef __UCLIBC_HAS_LFS__ +# error large file support is not enabled! +# endif + +# define freopen freopen64 +# define FILEDES_ARG (-2) +#else +# define FILEDES_ARG (-1) +#endif + +FILE *freopen(const char * __restrict filename, const char * __restrict mode, + register FILE * __restrict stream) +{ + /* + * ANSI/ISO allow (implementation-defined) change of mode for an + * existing file if filename is NULL. It doesn't look like Linux + * supports this, so we don't here. + * + * NOTE: Whether or not the stream is free'd on failure is unclear + * w.r.t. ANSI/ISO. This implementation chooses to NOT free + * the stream and associated buffer if they were dynamically + * allocated. + * NOTE: Previous versions of uClibc did free dynamic storage. + * + * TODO: Apparently linux allows setting append mode. Implement? + */ + unsigned short dynmode; + register FILE *fp; + __STDIO_AUTO_THREADLOCK_VAR; + + __STDIO_AUTO_THREADLOCK(stream); + + __STDIO_STREAM_VALIDATE(stream); + + /* First, flush and close, but don't deallocate, the stream. */ + /* This also removes the stream for the open file list. */ + dynmode = (stream->__modeflags & (__FLAG_FREEBUF|__FLAG_FREEFILE)); + + stream->__modeflags &= ~(__FLAG_FREEBUF|__FLAG_FREEFILE); + + /* Only call fclose on the stream if it is not already closed. */ + if ((stream->__modeflags & (__FLAG_READONLY|__FLAG_WRITEONLY)) + != (__FLAG_READONLY|__FLAG_WRITEONLY) + ) { + fclose(stream); /* Failures are ignored. */ + } + + fp = _stdio_fopen(((intptr_t) filename), mode, stream, FILEDES_ARG); + + /* Reset the allocation flags. */ + stream->__modeflags |= dynmode; + + __STDIO_AUTO_THREADUNLOCK(stream); + + return fp; +} |