1 files changed, 106 insertions, 0 deletions
diff --git a/libc/stdio/setvbuf.c b/libc/stdio/setvbuf.c
new file mode 100644
index 000000000..3fe62c6a8
--- /dev/null
+++ b/libc/stdio/setvbuf.c
@@ -0,0 +1,106 @@
+/* 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"
+
+#if (_IOFBF != 0) || (_IOLBF != 1) || (_IONBF != 2)
+#error Assumption violated -- values of _IOFBF, _IOLBF, _IONBF
+#endif
+#if (__FLAG_FBF != 0) || (__FLAG_NBF != (2*__FLAG_LBF))
+#error Assumption violated for buffering mode flags
+#endif
+
+int setvbuf(register FILE * __restrict stream, register char * __restrict buf,
+			int mode, size_t size)
+{
+#ifdef __STDIO_BUFFERS
+
+	int retval = EOF;
+	int alloc_flag = 0;
+	__STDIO_AUTO_THREADLOCK_VAR;
+
+	__STDIO_AUTO_THREADLOCK(stream);
+	__STDIO_STREAM_VALIDATE(stream);
+
+	if (((unsigned int) mode) > 2) {
+		__set_errno(EINVAL);
+		goto ERROR;
+	}
+
+	/* C99 states that setvbuf may only be used between a successful
+	 * open of the stream and before any other operation other than
+	 * an unsuccessful call to setvbuf. */
+
+#ifdef __STDIO_FLEXIBLE_SETVBUF
+	/* If we aren't currently reading (including ungots) or writing,
+	 * then allow the request to proceed. */
+
+	if (stream->__modeflags & (__MASK_READING|__FLAG_WRITING)) {
+		goto ERROR;
+	}
+#else
+	/* The following test isn't quite as strict as C99, as it will
+	 * not detect file positioning operations. */
+
+	if (stream->__modeflags & (__MASK_READING|__FLAG_WRITING
+							 |__FLAG_NARROW|__FLAG_WIDE
+							 |__FLAG_ERROR|__FLAG_EOF)
+		) {
+		goto ERROR;
+	}
+#endif
+
+	stream->__modeflags &= ~(__MASK_BUFMODE);	/* Clear current mode */
+	stream->__modeflags |= mode * __FLAG_LBF;	/*   and set new one. */
+
+	if ((mode == _IONBF) || !size) {
+		size = 0;
+		buf = NULL;
+	} else if (!buf) {
+		if ((__STDIO_STREAM_BUFFER_SIZE(stream) == size) /* Same size or */
+			|| !(buf = malloc(size)) /* malloc failed, so don't change. */
+			) {
+			goto DONE;
+		}
+		alloc_flag = __FLAG_FREEBUF;
+	}
+
+	if (stream->__modeflags & __FLAG_FREEBUF) {
+		stream->__modeflags &= ~(__FLAG_FREEBUF);
+		free(stream->__bufstart);
+	}
+
+	stream->__modeflags |= alloc_flag;
+	stream->__bufstart = buf;
+	stream->__bufend = buf + size;
+	__STDIO_STREAM_INIT_BUFREAD_BUFPOS(stream);
+	__STDIO_STREAM_DISABLE_GETC(stream);
+	__STDIO_STREAM_DISABLE_PUTC(stream);
+
+ DONE:
+	retval = 0;
+
+ ERROR:
+	__STDIO_STREAM_VALIDATE(stream);
+	__STDIO_AUTO_THREADUNLOCK(stream);
+
+	return retval;
+
+#else  /* __STDIO_BUFFERS  */
+
+	if (mode == _IONBF) {
+		return 0;
+	}
+
+	if (((unsigned int) mode) > 2) {
+		__set_errno(EINVAL);
+	}
+
+	return EOF;
+
+#endif
+}