Import sources from 2011-03-30 iso image

1 files changed, 48 insertions, 0 deletions

diff --git a/sys/src/libbio/bread.c b/sys/src/libbio/bread.c
new file mode 100755
index 000000000..9780ffac1
--- /dev/null
+++ b/sys/src/libbio/bread.c
@@ -0,0 +1,48 @@
+#include	<u.h>
+#include	<libc.h>
+#include	<bio.h>
+
+long
+Bread(Biobufhdr *bp, void *ap, long count)
+{
+	long c;
+	uchar *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;
+	if(count == c && bp->state == Binactive)
+		return -1;
+	return count-c;
+}