fix context respect through fuse reading

core/commands/refs.go

@@ -254,7 +254,7 @@ func (rw *RefWriter) writeRefsRecursive(n *dag.Node) (int, error) {
 			return count, err
 		}
 
-		nd, err := ng.Get()
+		nd, err := ng.Get(rw.Ctx)
 		if err != nil {
 			return count, err
 		}

fuse/ipns/ipns_unix.go

@@ -6,7 +6,6 @@ package ipns
 
 import (
 	"errors"
-	"io"
 	"os"
 
 	fuse "github.com/jbenet/go-ipfs/Godeps/_workspace/src/bazil.org/fuse"
@@ -274,32 +273,26 @@ func (dir *Directory) ReadDirAll(ctx context.Context) ([]fuse.Dirent, error) {
 }
 
 func (fi *File) Read(ctx context.Context, req *fuse.ReadRequest, resp *fuse.ReadResponse) error {
-	errs := make(chan error, 1)
-	go func() {
 	_, err := fi.fi.Seek(req.Offset, os.SEEK_SET)
 	if err != nil {
-			errs <- err
-			return
+		return err
 	}
 
 	fisize, err := fi.fi.Size()
 	if err != nil {
-			errs <- err
-			return
+		return err
 	}
 
-		readsize := min(req.Size, int(fisize-req.Offset))
-		n, err := io.ReadFull(fi.fi, resp.Data[:readsize])
-		resp.Data = resp.Data[:n]
-		errs <- err
-	}()
-
 	select {
 	case <-ctx.Done():
 		return ctx.Err()
-	case err := <-errs:
-		return err
+	default:
 	}
+
+	readsize := min(req.Size, int(fisize-req.Offset))
+	n, err := fi.fi.CtxReadFull(ctx, resp.Data[:readsize])
+	resp.Data = resp.Data[:n]
+	return err
 }
 
 func (fi *File) Write(ctx context.Context, req *fuse.WriteRequest, resp *fuse.WriteResponse) error {

ipnsfs/file.go

@@ -51,6 +51,13 @@ func (fi *File) Read(b []byte) (int, error) {
 	return fi.mod.Read(b)
 }
 
+// Read reads into the given buffer from the current offset
+func (fi *File) CtxReadFull(ctx context.Context, b []byte) (int, error) {
+	fi.Lock()
+	defer fi.Unlock()
+	return fi.mod.CtxReadFull(ctx, b)
+}
+
 // Close flushes, then propogates the modified dag node up the directory structure
 // and signals a republish to occur
 func (fi *File) Close() error {

merkledag/merkledag.go

@@ -257,10 +257,10 @@ type nodePromise struct {
 // from its internal channels, subsequent calls will return the
 // cached node.
 type NodeGetter interface {
-	Get() (*Node, error)
+	Get(context.Context) (*Node, error)
 }
 
-func (np *nodePromise) Get() (*Node, error) {
+func (np *nodePromise) Get(ctx context.Context) (*Node, error) {
 	if np.cache != nil {
 		return np.cache, nil
 	}
@@ -270,6 +270,8 @@ func (np *nodePromise) Get() (*Node, error) {
 		np.cache = blk
 	case <-np.ctx.Done():
 		return nil, np.ctx.Err()
+	case <-ctx.Done():
+		return nil, ctx.Err()
 	}
 	return np.cache, nil
 }

pin/pin.go

@@ -177,7 +177,7 @@ func (p *pinner) pinLinks(node *mdag.Node) error {
 	defer cancel()
 
 	for _, ng := range p.dserv.GetDAG(ctx, node) {
-		subnode, err := ng.Get()
+		subnode, err := ng.Get(ctx)
 		if err != nil {
 			// TODO: Maybe just log and continue?
 			return err

unixfs/io/dagreader.go

@@ -100,12 +100,13 @@ func newDataFileReader(ctx context.Context, n *mdag.Node, pb *ftpb.Data, serv md
 
 // precalcNextBuf follows the next link in line and loads it from the DAGService,
 // setting the next buffer to read from
-func (dr *DagReader) precalcNextBuf() error {
+func (dr *DagReader) precalcNextBuf(ctx context.Context) error {
 	dr.buf.Close() // Just to make sure
 	if dr.linkPosition >= len(dr.promises) {
 		return io.EOF
 	}
-	nxt, err := dr.promises[dr.linkPosition].Get()
+
+	nxt, err := dr.promises[dr.linkPosition].Get(ctx)
 	if err != nil {
 		return err
 	}
@@ -141,6 +142,11 @@ func (dr *DagReader) Size() int64 {
 
 // Read reads data from the DAG structured file
 func (dr *DagReader) Read(b []byte) (int, error) {
+	return dr.CtxReadFull(dr.ctx, b)
+}
+
+// CtxReadFull reads data from the DAG structured file
+func (dr *DagReader) CtxReadFull(ctx context.Context, b []byte) (int, error) {
 	// If no cached buffer, load one
 	total := 0
 	for {
@@ -161,7 +167,7 @@ func (dr *DagReader) Read(b []byte) (int, error) {
 		}
 
 		// Otherwise, load up the next block
-		err = dr.precalcNextBuf()
+		err = dr.precalcNextBuf(ctx)
 		if err != nil {
 			return total, err
 		}
@@ -183,7 +189,7 @@ func (dr *DagReader) WriteTo(w io.Writer) (int64, error) {
 		}
 
 		// Otherwise, load up the next block
-		err = dr.precalcNextBuf()
+		err = dr.precalcNextBuf(dr.ctx)
 		if err != nil {
 			if err == io.EOF {
 				return total, nil
@@ -239,7 +245,7 @@ func (dr *DagReader) Seek(offset int64, whence int) (int64, error) {
 		}
 
 		// start sub-block request
-		err := dr.precalcNextBuf()
+		err := dr.precalcNextBuf(dr.ctx)
 		if err != nil {
 			return 0, err
 		}

unixfs/mod/dagmodifier.go

@@ -315,32 +315,53 @@ func (dm *DagModifier) appendData(node *mdag.Node, blks <-chan []byte) (*mdag.No
 
 // Read data from this dag starting at the current offset
 func (dm *DagModifier) Read(b []byte) (int, error) {
-	err := dm.Sync()
+	err := dm.readPrep()
 	if err != nil {
 		return 0, err
 	}
 
+	n, err := dm.read.Read(b)
+	dm.curWrOff += uint64(n)
+	return n, err
+}
+
+func (dm *DagModifier) readPrep() error {
+	err := dm.Sync()
+	if err != nil {
+		return err
+	}
+
 	if dm.read == nil {
 		ctx, cancel := context.WithCancel(dm.ctx)
 		dr, err := uio.NewDagReader(ctx, dm.curNode, dm.dagserv)
 		if err != nil {
-			return 0, err
+			return err
 		}
 
 		i, err := dr.Seek(int64(dm.curWrOff), os.SEEK_SET)
 		if err != nil {
-			return 0, err
+			return err
 		}
 
 		if i != int64(dm.curWrOff) {
-			return 0, ErrSeekFail
+			return ErrSeekFail
 		}
 
 		dm.readCancel = cancel
 		dm.read = dr
 	}
 
-	n, err := dm.read.Read(b)
+	return nil
+}
+
+// Read data from this dag starting at the current offset
+func (dm *DagModifier) CtxReadFull(ctx context.Context, b []byte) (int, error) {
+	err := dm.readPrep()
+	if err != nil {
+		return 0, err
+	}
+
+	n, err := dm.read.CtxReadFull(ctx, b)
 	dm.curWrOff += uint64(n)
 	return n, err
 }

unixfs/tar/reader.go

@@ -90,7 +90,7 @@ func (r *Reader) writeToBuf(dagnode *mdag.Node, path string, depth int) {
 		defer cancel()
 
 		for i, ng := range r.dag.GetDAG(ctx, dagnode) {
-			childNode, err := ng.Get()
+			childNode, err := ng.Get(ctx)
 			if err != nil {
 				r.emitError(err)
 				return