1 files changed, 71 insertions, 0 deletions
diff --git a/src/libbio/bread.c b/src/libbio/bread.c
new file mode 100644
index 000000000..5cf9a05c8
--- /dev/null
+++ b/src/libbio/bread.c
@@ -0,0 +1,71 @@
+/*
+http://code.google.com/p/inferno-os/source/browse/libbio/bread.c
+
+	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+	Revisions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com).  All rights reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include	<u.h>
+#include	<libc.h>
+#include	<bio.h>
+
+long
+Bread(Biobuf *bp, void *ap, long count)
+{
+	long c;
+	unsigned char *p;
+	int i, n, ic;
+
+	p = ap;
+	c = count;
+	ic = bp->icount;
+
+	while(c > 0) {
+		n = -ic;
+		if(n > c)
+			n = c;
+		if(n == 0) {
+			if(bp->state != Bractive)
+				break;
+			i = read(bp->fid, bp->bbuf, bp->bsize);
+			if(i <= 0) {
+				bp->state = Bracteof;
+				if(i < 0)
+					bp->state = Binactive;
+				break;
+			}
+			bp->gbuf = bp->bbuf;
+			bp->offset += i;
+			if(i < bp->bsize) {
+				memmove(bp->ebuf-i, bp->bbuf, i);
+				bp->gbuf = bp->ebuf-i;
+			}
+			ic = -i;
+			continue;
+		}
+		memmove(p, bp->ebuf+ic, n);
+		c -= n;
+		ic += n;
+		p += n;
+	}
+	bp->icount = ic;
+	return count-c;
+}