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-rw-r--r--stdio/setvbuf.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/stdio/setvbuf.c b/stdio/setvbuf.c
new file mode 100644
index 0000000..8c33386
--- /dev/null
+++ b/stdio/setvbuf.c
@@ -0,0 +1,85 @@
+/* Copyright (C) 1991, 1993 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., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#include <ansidecl.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.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
+DEFUN(setvbuf, (stream, buf, mode, size),
+ FILE *stream AND char *buf AND int mode AND size_t size)
+{
+ if (!__validfp(stream))
+ {
+ 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:
+ 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)
+ {
+ 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;
+}