move coreos-cloudinit into config/cloudinit

Signed-off-by: Sven Dowideit <SvenDowideit@home.org.au>

config/cloudinit/system/file.go

@@ -0,0 +1,115 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package system
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path"
+	"strconv"
+
+	"github.com/rancher/os/config/cloudinit/config"
+)
+
+// File is a top-level structure which embeds its underlying configuration,
+// config.File, and provides the system-specific Permissions().
+type File struct {
+	config.File
+}
+
+func (f *File) Permissions() (os.FileMode, error) {
+	if f.RawFilePermissions == "" {
+		return os.FileMode(0644), nil
+	}
+
+	// Parse string representation of file mode as integer
+	perm, err := strconv.ParseInt(f.RawFilePermissions, 8, 32)
+	if err != nil {
+		return 0, fmt.Errorf("Unable to parse file permissions %q as integer", f.RawFilePermissions)
+	}
+	return os.FileMode(perm), nil
+}
+
+// WriteFile writes given endecoded file to the filesystem
+func WriteFile(f *File, root string) (string, error) {
+	if f.Encoding != "" {
+		return "", fmt.Errorf("Unable to write file with encoding %s", f.Encoding)
+	}
+
+	fullpath := path.Join(root, f.Path)
+	dir := path.Dir(fullpath)
+	log.Printf("Writing file to %q", fullpath)
+
+	if err := EnsureDirectoryExists(dir); err != nil {
+		return "", err
+	}
+
+	perm, err := f.Permissions()
+	if err != nil {
+		return "", err
+	}
+
+	var tmp *os.File
+	// Create a temporary file in the same directory to ensure it's on the same filesystem
+	if tmp, err = ioutil.TempFile(dir, "cloudinit-temp"); err != nil {
+		return "", err
+	}
+
+	if err := ioutil.WriteFile(tmp.Name(), []byte(f.Content), perm); err != nil {
+		return "", err
+	}
+
+	if err := tmp.Close(); err != nil {
+		return "", err
+	}
+
+	// Ensure the permissions are as requested (since WriteFile can be affected by sticky bit)
+	if err := os.Chmod(tmp.Name(), perm); err != nil {
+		return "", err
+	}
+
+	if f.Owner != "" {
+		// We shell out since we don't have a way to look up unix groups natively
+		cmd := exec.Command("chown", f.Owner, tmp.Name())
+		if err := cmd.Run(); err != nil {
+			return "", err
+		}
+	}
+
+	if err := os.Rename(tmp.Name(), fullpath); err != nil {
+		return "", err
+	}
+
+	log.Printf("Wrote file to %q", fullpath)
+	return fullpath, nil
+}
+
+func EnsureDirectoryExists(dir string) error {
+	info, err := os.Stat(dir)
+	if err == nil {
+		if !info.IsDir() {
+			return fmt.Errorf("%s is not a directory", dir)
+		}
+	} else {
+		err = os.MkdirAll(dir, 0755)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}