ref: 1adef91a41d208f395953fec4c335d1580c0814b
parent: 2d46e781f5fe750468e4ff9300a7fe2c81c855f5
author: Ori Bernstein <ori@eigenstate.org>
date: Sat Feb 6 14:01:04 EST 2016
Fix bio bug. Shift the start of the buffer down when filling if needed.
--- a/lib/bio/bio.myr
+++ b/lib/bio/bio.myr
@@ -185,7 +185,7 @@
returning the number of bytes read.
*/
const read = {f, dst- var count : std.size
+ var count, cap : std.size
var d : byte[:]
/* Clear the error state so we can retry */
@@ -204,10 +204,11 @@
;;
std.assert(f.mode & Rd != 0, "File is not in read mode")
/*
- * small reads should try to fill, so we don't have to make a
- * syscall for every read
- */
- if dst.len < Small
+ small reads should try to fill, so we don't have to make a
+ syscall for every read
+ */
+ cap = f.rend - f.rstart
+ if dst.len < Small && cap < dst.len
fill(f, dst.len)
;;
/* Read as much as we can from the buffer */
@@ -562,18 +563,10 @@
*/
const ensureread = {f, nvar held
- var cap
std.assert(n < f.rbuf.len, "ensured read capacity > buffer size")
held = f.rend - f.rstart
if n > held
- /* if we need to shift the slice down to the start, do it */
- cap = f.rend - f.rstart
- if n > (cap + held)
- std.slcp(f.rbuf[:cap], f.rbuf[f.rstart:f.rend])
- f.rstart = 0
- f.rend = cap
- ;;
match fill(f, n)
| `Eof: -> `Eof
| `Err e: -> `Err e
@@ -616,12 +609,20 @@
the read buffer.
*/
const fill = {f, min- var count
+ var count, cap
count = 0
/* Clear the error state so we can retry */
if f.lasterr != 0
-> `Err geterr(f)
+ ;;
+
+ /* if we need to shift the slice down to the start, do it */
+ cap = f.rend - f.rstart
+ if min > cap
+ std.slcp(f.rbuf[:cap], f.rbuf[f.rstart:f.rend])
+ f.rstart = 0
+ f.rend = cap
;;
while count < min
/*