Merge pull request #7036 from arizvisa/safe.packer-config_file_unix

Replaced unsafe method of determining a user's home directory with an implementation based on os/user.

packer/config_file.go

@@ -1,7 +1,9 @@
 package packer
 
 import (
+	"log"
 	"os"
+	"os/user"
 	"path/filepath"
 )
 
@@ -38,3 +40,47 @@ func ConfigTmpDir() (string, error) {
 	}
 	return td, nil
 }
+
+func homeDir() (string, error) {
+
+	// First prefer the HOME environmental variable
+	if home := os.Getenv("HOME"); home != "" {
+		log.Printf("Detected home directory from env var: %s", home)
+		return home, nil
+	}
+
+	// Fall back to the passwd database if not found which follows
+	// the same semantics as bourne shell
+	u, err := user.Current()
+
+	// Get homedir from specified username
+	// if it is set and different than what we have
+	if username := os.Getenv("USER"); username != "" && err == nil && u.Username != username {
+		u, err = user.Lookup(username)
+	}
+
+	// Fail if we were unable to read the record
+	if err != nil {
+		return "", err
+	}
+
+	return u.HomeDir, nil
+}
+
+func configFile() (string, error) {
+	dir, err := homeDir()
+	if err != nil {
+		return "", err
+	}
+
+	return filepath.Join(dir, defaultConfigFile), nil
+}
+
+func configDir() (string, error) {
+	dir, err := homeDir()
+	if err != nil {
+		return "", err
+	}
+
+	return filepath.Join(dir, defaultConfigDir), nil
+}

packer/config_file_unix.go

@@ -2,53 +2,7 @@
 
 package packer
 
-import (
-	"bytes"
-	"errors"
-	"log"
-	"os"
-	"os/exec"
-	"path/filepath"
-	"strings"
+const (
+	defaultConfigFile = ".packerconfig"
+	defaultConfigDir  = ".packer.d"
 )
-
-func configFile() (string, error) {
-	dir, err := homeDir()
-	if err != nil {
-		return "", err
-	}
-
-	return filepath.Join(dir, ".packerconfig"), nil
-}
-
-func configDir() (string, error) {
-	dir, err := homeDir()
-	if err != nil {
-		return "", err
-	}
-
-	return filepath.Join(dir, ".packer.d"), nil
-}
-
-func homeDir() (string, error) {
-	// First prefer the HOME environmental variable
-	if home := os.Getenv("HOME"); home != "" {
-		log.Printf("Detected home directory from env var: %s", home)
-		return home, nil
-	}
-
-	// If that fails, try the shell
-	var stdout bytes.Buffer
-	cmd := exec.Command("sh", "-c", "eval echo ~$USER")
-	cmd.Stdout = &stdout
-	if err := cmd.Run(); err != nil {
-		return "", err
-	}
-
-	result := strings.TrimSpace(stdout.String())
-	if result == "" {
-		return "", errors.New("blank output")
-	}
-
-	return result, nil
-}

packer/config_file_windows.go

@@ -2,45 +2,7 @@
 
 package packer
 
-import (
-	"path/filepath"
-	"syscall"
-	"unsafe"
+const (
+	defaultConfigFile = "packer.config"
+	defaultConfigDir  = "packer.d"
 )
-
-var (
-	shell         = syscall.MustLoadDLL("Shell32.dll")
-	getFolderPath = shell.MustFindProc("SHGetFolderPathW")
-)
-
-const CSIDL_APPDATA = 26
-
-func configFile() (string, error) {
-	dir, err := homeDir()
-	if err != nil {
-		return "", err
-	}
-
-	return filepath.Join(dir, "packer.config"), nil
-}
-
-func configDir() (string, error) {
-	dir, err := homeDir()
-	if err != nil {
-		return "", err
-	}
-
-	return filepath.Join(dir, "packer.d"), nil
-}
-
-func homeDir() (string, error) {
-	b := make([]uint16, syscall.MAX_PATH)
-
-	// See: http://msdn.microsoft.com/en-us/library/windows/desktop/bb762181(v=vs.85).aspx
-	r, _, err := getFolderPath.Call(0, CSIDL_APPDATA, 0, 0, uintptr(unsafe.Pointer(&b[0])))
-	if uint32(r) != 0 {
-		return "", err
-	}
-
-	return syscall.UTF16ToString(b), nil
-}