From 38425b1a06514265f0944fb129b4a47fb59789fd Mon Sep 17 00:00:00 2001
From: Juan Batiz-Benet <juan@benet.ai>
Date: Mon, 2 Mar 2015 06:12:54 -0800
Subject: [PATCH] fuse: fix read problem in osx

@whyrusleeping's fix in c88340b broke reading fuse in osx.
i'm not sure why... anyway, i chose to revert back to
io.ReadFull, but use the min of req.Size and r.Size(), which
should not encounter the reading problem in linux that a77ea2f
fixed in the first place.

This commit also changes ipns, which had not been changed.
---
 fuse/ipns/ipns_unix.go         | 11 ++++++++++-
 fuse/readonly/readonly_unix.go | 13 ++++++++++---
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/fuse/ipns/ipns_unix.go b/fuse/ipns/ipns_unix.go
index 2ced56339..edb126f6c 100644
--- a/fuse/ipns/ipns_unix.go
+++ b/fuse/ipns/ipns_unix.go
@@ -354,7 +354,9 @@ func (s *Node) Read(ctx context.Context, req *fuse.ReadRequest, resp *fuse.ReadR
 	if err != nil {
 		return err
 	}
-	n, err := io.ReadFull(r, resp.Data[:req.Size])
+
+	buf := resp.Data[:min(req.Size, int(r.Size()))]
+	n, err := io.ReadFull(r, buf)
 	resp.Data = resp.Data[:n]
 	lm["res_size"] = n
 	return err // may be non-nil / not succeeded
@@ -652,3 +654,10 @@ type ipnsNode interface {
 }
 
 var _ ipnsNode = (*Node)(nil)
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
diff --git a/fuse/readonly/readonly_unix.go b/fuse/readonly/readonly_unix.go
index 543ec0d4a..ed4b80f5d 100644
--- a/fuse/readonly/readonly_unix.go
+++ b/fuse/readonly/readonly_unix.go
@@ -5,7 +5,6 @@
 package readonly
 
 import (
-	"bytes"
 	"io"
 	"os"
 
@@ -169,8 +168,9 @@ func (s *Node) Read(ctx context.Context, req *fuse.ReadRequest, resp *fuse.ReadR
 	if err != nil {
 		return err
 	}
-	buf := bytes.NewBuffer(resp.Data)
-	n, err := io.CopyN(buf, r, int64(req.Size))
+
+	buf := resp.Data[:min(req.Size, int(r.Size()))]
+	n, err := io.ReadFull(r, buf)
 	if err != nil && err != io.EOF {
 		return err
 	}
@@ -196,3 +196,10 @@ type roNode interface {
 }
 
 var _ roNode = (*Node)(nil)
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}