buf size off-by-one

Reference: /n/sources/patch/applied/sambufsz
Date: Fri Jan 29 07:04:24 CET 2010
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/sam/file.c	Fri Jan 29 07:04:01 2010
+++ /sys/src/cmd/sam/file.c	Fri Jan 29 07:04:00 2010
@@ -139,7 +139,7 @@
 
 	if(merge.f != f
 	|| p0-(merge.p0+merge.n)>Maxmerge			/* too far */
-	|| merge.nbuf+((p0+ns)-(merge.p0+merge.n))>RBUFSIZE)	/* too long */
+	|| merge.nbuf+((p0+ns)-(merge.p0+merge.n))>=RBUFSIZE)	/* too long */
 		flushmerge();
 
 	if(ns>=RBUFSIZE){
@@ -178,7 +178,7 @@
 
 	if(merge.f != f
 	|| p0-(merge.p0+merge.n)>Maxmerge			/* too far */
-	|| merge.nbuf+(p0-(merge.p0+merge.n))>RBUFSIZE){	/* too long */
+	|| merge.nbuf+(p0-(merge.p0+merge.n))>=RBUFSIZE){	/* too long */
 		flushmerge();
 		merge.f = f;
 		merge.p0 = p0;