Added support for mknod(2).

For #137.
GoogleCloudPlatform · Dec 15, 2015 · a6f9ff1 · a6f9ff1
2 parents 0d2fd94 + cdc0e77
commit a6f9ff1
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Showing 7 changed files with 211 additions and 21 deletions.
diff --git a/internal/fs/fs.go b/internal/fs/fs.go
@@ -1056,18 +1056,49 @@ func (fs *fileSystem) MkDir(
 }
 
 // LOCKS_EXCLUDED(fs.mu)
-func (fs *fileSystem) CreateFile(
+func (fs *fileSystem) MkNode(
 	ctx context.Context,
-	op *fuseops.CreateFileOp) (err error) {
+	op *fuseops.MkNodeOp) (err error) {
+	// Create the child.
+	child, err := fs.createFile(ctx, op.Parent, op.Name, op.Mode)
+	if err != nil {
+		return
+	}
+
+	defer fs.unlockAndMaybeDisposeOfInode(child, &err)
+
+	// Fill out the response.
+	e := &op.Entry
+	e.Child = child.ID()
+	e.Attributes, e.AttributesExpiration, err = fs.getAttributes(ctx, child)
+
+	if err != nil {
+		err = fmt.Errorf("getAttributes: %v", err)
+		return
+	}
+
+	return
+}
+
+// Create a child of the parent with the given ID, returning the child locked
+// and with its lookup count incremented.
+//
+// LOCKS_EXCLUDED(fs.mu)
+// LOCK_FUNCTION(child)
+func (fs *fileSystem) createFile(
+	ctx context.Context,
+	parentID fuseops.InodeID,
+	name string,
+	mode os.FileMode) (child inode.Inode, err error) {
 	// Find the parent.
 	fs.mu.Lock()
-	parent := fs.inodes[op.Parent].(inode.DirInode)
+	parent := fs.inodes[parentID].(inode.DirInode)
 	fs.mu.Unlock()
 
 	// Create an empty backing object for the child, failing if it already
 	// exists.
 	parent.Lock()
-	o, err := parent.CreateChildFile(ctx, op.Name)
+	o, err := parent.CreateChildFile(ctx, name)
 	parent.Unlock()
 
 	// Special case: *gcs.PreconditionError means the name already exists.
@@ -1086,12 +1117,25 @@ func (fs *fileSystem) CreateFile(
 	// do so, it means someone beat us to the punch with a newer generation
 	// (unlikely, so we're probably okay with failing here).
 	fs.mu.Lock()
-	child := fs.lookUpOrCreateInodeIfNotStale(o.Name, o)
+	child = fs.lookUpOrCreateInodeIfNotStale(o.Name, o)
 	if child == nil {
 		err = fmt.Errorf("Newly-created record is already stale")
 		return
 	}
 
+	return
+}
+
+// LOCKS_EXCLUDED(fs.mu)
+func (fs *fileSystem) CreateFile(
+	ctx context.Context,
+	op *fuseops.CreateFileOp) (err error) {
+	// Create the child.
+	child, err := fs.createFile(ctx, op.Parent, op.Name, op.Mode)
+	if err != nil {
+		return
+	}
+
 	defer fs.unlockAndMaybeDisposeOfInode(child, &err)
 
 	// Allocate a handle.

diff --git a/internal/fs/local_modifications_test.go b/internal/fs/local_modifications_test.go
@@ -404,6 +404,86 @@ func (t *OpenTest) IllegalNames() {
 	}
 }
 
+////////////////////////////////////////////////////////////////////////
+// Mknod
+////////////////////////////////////////////////////////////////////////
+
+type MknodTest struct {
+	fsTest
+}
+
+func init() { RegisterTestSuite(&MknodTest{}) }
+
+func (t *MknodTest) File() {
+	// mknod(2) only works for root on OS X.
+	if runtime.GOOS == "darwin" { return }
+
+	var err error
+	p := path.Join(t.mfs.Dir(), "foo")
+
+	// Create
+	err = syscall.Mknod(p, syscall.S_IFREG|0600, 0)
+	AssertEq(nil, err)
+
+	// Stat
+	fi, err := os.Stat(p)
+	AssertEq(nil, err)
+
+	ExpectEq(path.Base(p), fi.Name())
+	ExpectEq(0, fi.Size())
+	ExpectEq(filePerms, fi.Mode())
+
+	// Read
+	contents, err := ioutil.ReadFile(p)
+	AssertEq(nil, err)
+	ExpectEq("", string(contents))
+}
+
+func (t *MknodTest) Directory() {
+	// mknod(2) only works for root on OS X.
+	if runtime.GOOS == "darwin" { return }
+
+	var err error
+	p := path.Join(t.mfs.Dir(), "foo")
+
+	// Quoth `man 2 mknod`: "Under Linux, this call cannot be used to create
+	// directories."
+	err = syscall.Mknod(p, syscall.S_IFDIR|0700, 0)
+	ExpectEq(syscall.EPERM, err)
+}
+
+func (t *MknodTest) AlreadyExists() {
+	// mknod(2) only works for root on OS X.
+	if runtime.GOOS == "darwin" { return }
+
+	var err error
+	p := path.Join(t.mfs.Dir(), "foo")
+
+	// Create (first)
+	err = ioutil.WriteFile(p, []byte("taco"), 0600)
+	AssertEq(nil, err)
+
+	// Create (second)
+	err = syscall.Mknod(p, syscall.S_IFREG|0600, 0)
+	ExpectEq(syscall.EEXIST, err)
+
+	// Read
+	contents, err := ioutil.ReadFile(p)
+	AssertEq(nil, err)
+	ExpectEq("taco", string(contents))
+}
+
+func (t *MknodTest) NonExistentParent() {
+	// mknod(2) only works for root on OS X.
+	if runtime.GOOS == "darwin" { return }
+
+	var err error
+	p := path.Join(t.mfs.Dir(), "foo/bar")
+
+	err = syscall.Mknod(p, syscall.S_IFREG|0600, 0)
+	ExpectEq(syscall.ENOENT, err)
+}
+
 ////////////////////////////////////////////////////////////////////////
 // Modes
 ////////////////////////////////////////////////////////////////////////

diff --git a/vendor/github.com/jacobsa/fuse/conversions.go b/vendor/github.com/jacobsa/fuse/conversions.go
diff --git a/vendor/github.com/jacobsa/fuse/fuseops/ops.go b/vendor/github.com/jacobsa/fuse/fuseops/ops.go
diff --git a/vendor/github.com/jacobsa/fuse/fuseutil/file_system.go b/vendor/github.com/jacobsa/fuse/fuseutil/file_system.go
diff --git a/vendor/github.com/jacobsa/fuse/fuseutil/not_implemented_file_system.go b/vendor/github.com/jacobsa/fuse/fuseutil/not_implemented_file_system.go
diff --git a/vendor/vendor.json b/vendor/vendor.json
@@ -9,43 +9,43 @@
 		},
 		{
 			"path": "github.com/jacobsa/fuse",
-			"revision": "bc664bf39be72bcf975d71007fa767f15d3a7d7c",
-			"revisionTime": "2015-09-10T13:55:51+10:00"
+			"revision": "895b8c415580ff864f707cc0016b08ff840cd23b",
+			"revisionTime": "2015-12-15T10:55:29+11:00"
 		},
 		{
 			"path": "github.com/jacobsa/fuse/fsutil",
-			"revision": "bc664bf39be72bcf975d71007fa767f15d3a7d7c",
-			"revisionTime": "2015-09-10T13:55:51+10:00"
+			"revision": "895b8c415580ff864f707cc0016b08ff840cd23b",
+			"revisionTime": "2015-12-15T10:55:29+11:00"
 		},
 		{
 			"path": "github.com/jacobsa/fuse/fuseops",
-			"revision": "bc664bf39be72bcf975d71007fa767f15d3a7d7c",
-			"revisionTime": "2015-09-10T13:55:51+10:00"
+			"revision": "895b8c415580ff864f707cc0016b08ff840cd23b",
+			"revisionTime": "2015-12-15T10:55:29+11:00"
 		},
 		{
 			"path": "github.com/jacobsa/fuse/fusetesting",
-			"revision": "bc664bf39be72bcf975d71007fa767f15d3a7d7c",
-			"revisionTime": "2015-09-10T13:55:51+10:00"
+			"revision": "895b8c415580ff864f707cc0016b08ff840cd23b",
+			"revisionTime": "2015-12-15T10:55:29+11:00"
 		},
 		{
 			"path": "github.com/jacobsa/fuse/fuseutil",
-			"revision": "bc664bf39be72bcf975d71007fa767f15d3a7d7c",
-			"revisionTime": "2015-09-10T13:55:51+10:00"
+			"revision": "895b8c415580ff864f707cc0016b08ff840cd23b",
+			"revisionTime": "2015-12-15T10:55:29+11:00"
 		},
 		{
 			"path": "github.com/jacobsa/fuse/internal/buffer",
-			"revision": "bc664bf39be72bcf975d71007fa767f15d3a7d7c",
-			"revisionTime": "2015-09-10T13:55:51+10:00"
+			"revision": "895b8c415580ff864f707cc0016b08ff840cd23b",
+			"revisionTime": "2015-12-15T10:55:29+11:00"
 		},
 		{
 			"path": "github.com/jacobsa/fuse/internal/freelist",
-			"revision": "bc664bf39be72bcf975d71007fa767f15d3a7d7c",
-			"revisionTime": "2015-09-10T13:55:51+10:00"
+			"revision": "895b8c415580ff864f707cc0016b08ff840cd23b",
+			"revisionTime": "2015-12-15T10:55:29+11:00"
 		},
 		{
 			"path": "github.com/jacobsa/fuse/internal/fusekernel",
-			"revision": "bc664bf39be72bcf975d71007fa767f15d3a7d7c",
-			"revisionTime": "2015-09-10T13:55:51+10:00"
+			"revision": "895b8c415580ff864f707cc0016b08ff840cd23b",
+			"revisionTime": "2015-12-15T10:55:29+11:00"
 		},
 		{
 			"path": "github.com/jacobsa/gcloud/gcs",