iso_config: allow for subdirs in hash sum files

Allow hash sum files and ISOs to be in different directories as
Ubuntu does.

Signed-off-by: Pavel Boldin <boldin.pavel@gmail.com>

common/iso_config.go

@@ -140,9 +140,20 @@ func (c *ISOConfig) parseCheckSumFile(rd *bufio.Reader) error {
 	if err != nil {
 		return err
 	}
+
+	checksumurl, err := url.Parse(c.ISOChecksumURL)
+	if err != nil {
+		return err
+	}
+
+	relpath, err := filepath.Rel(filepath.Dir(checksumurl.Path), u.Path)
+	if err != nil {
+		return err
+	}
+
 	filename := filepath.Base(u.Path)
 
-	errNotFound := fmt.Errorf("No checksum for %q found at: %s", filename, c.ISOChecksumURL)
+	errNotFound := fmt.Errorf("No checksum for %q or %q found at: %s", filename, relpath, c.ISOChecksumURL)
 	for {
 		line, err := rd.ReadString('\n')
 		if err != nil && line == "" {
@@ -154,7 +165,8 @@ func (c *ISOConfig) parseCheckSumFile(rd *bufio.Reader) error {
 		}
 		if strings.ToLower(parts[0]) == c.ISOChecksumType {
 			// BSD-style checksum
-			if parts[1] == fmt.Sprintf("(%s)", filename) {
+			if parts[1] == fmt.Sprintf("(%s)", filename) || parts[1] == fmt.Sprintf("(%s)", relpath) ||
+				parts[1] == fmt.Sprintf("(./%s)", relpath) {
 				c.ISOChecksum = parts[3]
 				return nil
 			}
@@ -164,7 +176,7 @@ func (c *ISOConfig) parseCheckSumFile(rd *bufio.Reader) error {
 				// Binary mode
 				parts[1] = parts[1][1:]
 			}
-			if parts[1] == filename {
+			if parts[1] == filename || parts[1] == relpath || parts[1] == "./"+relpath {
 				c.ISOChecksum = parts[0]
 				return nil
 			}

common/iso_config_test.go

@@ -24,11 +24,21 @@ MD5 (other.iso) = bAr
 MD5 (the-OS.iso) = baZ
 `
 
+var cs_bsd_style_subdir = `
+MD5 (other.iso) = bAr
+MD5 (./subdir/the-OS.iso) = baZ
+`
+
 var cs_gnu_style = `
 bAr0 *the-OS.iso
 baZ0  other.iso
 `
 
+var cs_gnu_style_subdir = `
+bAr0 *./subdir/the-OS.iso
+baZ0  other.iso
+`
+
 var cs_bsd_style_no_newline = `
 MD5 (other.iso) = bAr
 MD5 (the-OS.iso) = baZ`
@@ -134,6 +144,27 @@ func TestISOConfigPrepare_ISOChecksumURL(t *testing.T) {
 		t.Fatalf("should've found \"baz\" got: %s", i.ISOChecksum)
 	}
 
+	// Test good - ISOChecksumURL BSD style with relative path
+	i = testISOConfig()
+	i.ISOChecksum = ""
+
+	cs_dir, _ := ioutil.TempDir("", "packer-testdir-")
+	cs_file, _ = ioutil.TempFile(cs_dir, "packer-test-")
+	ioutil.WriteFile(cs_file.Name(), []byte(cs_bsd_style_subdir), 0666)
+	i.ISOChecksumURL = fmt.Sprintf("%s%s", filePrefix, cs_file.Name())
+	i.RawSingleISOUrl = fmt.Sprintf("%s%s", cs_dir, "/subdir/the-OS.iso")
+	warns, err = i.Prepare(nil)
+	if len(warns) > 0 {
+		t.Fatalf("bad: %#v", warns)
+	}
+	if err != nil {
+		t.Fatalf("should not have error: %s", err)
+	}
+
+	if i.ISOChecksum != "baz" {
+		t.Fatalf("should've found \"baz\" got: %s", i.ISOChecksum)
+	}
+
 	// Test good - ISOChecksumURL GNU style no newline
 	i = testISOConfig()
 	i.ISOChecksum = ""
@@ -171,6 +202,26 @@ func TestISOConfigPrepare_ISOChecksumURL(t *testing.T) {
 	if i.ISOChecksum != "bar0" {
 		t.Fatalf("should've found \"bar0\" got: %s", i.ISOChecksum)
 	}
+
+	// Test good - ISOChecksumURL GNU style with relative path
+	i = testISOConfig()
+	i.ISOChecksum = ""
+
+	cs_file, _ = ioutil.TempFile(cs_dir, "packer-test-")
+	ioutil.WriteFile(cs_file.Name(), []byte(cs_gnu_style_subdir), 0666)
+	i.ISOChecksumURL = fmt.Sprintf("%s%s", filePrefix, cs_file.Name())
+	i.RawSingleISOUrl = fmt.Sprintf("%s%s", cs_dir, "/subdir/the-OS.iso")
+	warns, err = i.Prepare(nil)
+	if len(warns) > 0 {
+		t.Fatalf("bad: %#v", warns)
+	}
+	if err != nil {
+		t.Fatalf("should not have error: %s", err)
+	}
+
+	if i.ISOChecksum != "bar0" {
+		t.Fatalf("should've found \"bar0\" got: %s", i.ISOChecksum)
+	}
 }
 
 func TestISOConfigPrepare_ISOChecksumType(t *testing.T) {