/* Copyright (C) 1991, 1993, 1995, 1996, 1997 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. The GNU C Library 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 Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with the GNU C Library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include <stddef.h> #include <stdio.h> #include <stdlib.h> #include <errno.h> /* Make STREAM use the buffering method given in MODE. If MODE indicates full or line buffering, use BUF, a buffer of SIZE bytes; if BUF is NULL, malloc a buffer. */ int setvbuf (stream, buf, mode, size) FILE *stream; char *buf; int mode; size_t size; { if (!__validfp (stream)) { __set_errno (EINVAL); return EOF; } /* The ANSI standard says setvbuf can only be called before any I/O is done, but we allow it to replace an old buffer, flushing it first. */ if (stream->__buffer != NULL) { (void) fflush (stream); /* Free the old buffer if it was malloc'd. */ if (!stream->__userbuf) free(stream->__buffer); } stream->__get_limit = stream->__put_limit = NULL; stream->__bufp = stream->__buffer = NULL; stream->__userbuf = stream->__linebuf = stream->__linebuf_active = 0; switch (mode) { default: __set_errno (EINVAL); return EOF; case _IONBF: /* Unbuffered. */ stream->__buffer = NULL; stream->__bufsize = 0; stream->__userbuf = 1; break; case _IOLBF: /* Line buffered. */ stream->__linebuf = 1; case _IOFBF: /* Fully buffered. */ if (size == 0) { __set_errno (EINVAL); return EOF; } stream->__bufsize = size; if (buf != NULL) stream->__userbuf = 1; else if ((buf = (char *) malloc (size)) == NULL) return EOF; stream->__buffer = buf; break; } stream->__bufp = stream->__buffer; stream->__get_limit = stream->__buffer; /* The next output operation will prime the stream for writing. */ stream->__put_limit = stream->__buffer; return 0; }