Initial revision

lib/stdio/fillbuf.c

@@ -0,0 +1,69 @@
+/*
+ * fillbuf.c - fill a buffer
+ */
+/* $Header$ */
+
+#if	defined(_POSIX_SOURCE)
+#include	<sys/types.h>
+#endif
+#include	<stdio.h>
+#include	<stdlib.h>
+#include	"loc_incl.h"
+
+ssize_t _read(ssize_t d, char *buf, size_t nbytes);
+
+int
+__fillbuf(register FILE *stream)
+{
+	static unsigned char ch[FOPEN_MAX];
+	register int i;
+
+	stream->_count = 0;
+	if (fileno(stream) < 0) return EOF;
+	if (io_testflag(stream, (_IOEOF | _IOERR ))) return EOF; 
+	if (!io_testflag(stream, _IOREAD))
+	     { stream->_flags |= _IOERR; return EOF; }
+	if (io_testflag(stream, _IOWRITING))
+	     { stream->_flags |= _IOERR; return EOF; }
+
+	if (!io_testflag(stream, _IOREADING))
+		stream->_flags |= _IOREADING;
+	
+	if (!io_testflag(stream, _IONBF) && !stream->_buf) {
+		stream->_buf = (unsigned char *) malloc(BUFSIZ);
+		if (!stream->_buf) {
+			stream->_flags |= _IONBF;
+		}
+		else {
+			stream->_flags |= _IOMYBUF;
+			stream->_bufsiz = BUFSIZ;
+		}
+	}
+
+	/* flush line-buffered output when filling an input buffer */
+	for (i = 0; i < FOPEN_MAX; i++) {
+		if (__iotab[i] && io_testflag(__iotab[i], _IOLBF))
+			if (io_testflag(__iotab[i], _IOWRITING))
+				(void) fflush(__iotab[i]);
+	}
+
+	if (!stream->_buf) {
+		stream->_buf = &ch[fileno(stream)];
+		stream->_bufsiz = 1;
+	}
+	stream->_ptr = stream->_buf;
+	stream->_count = _read(stream->_fd, (char *)stream->_buf, stream->_bufsiz);
+
+	if (stream->_count <= 0){
+		if (stream->_count == 0) {
+			stream->_flags |= _IOEOF;
+		}
+		else 
+			stream->_flags |= _IOERR;
+
+		return EOF;
+	}
+	stream->_count--;
+
+	return *stream->_ptr++;
+}