deviceinfo: implement a new simple parser (MR 4)

This replaces an external toml library with a simple parser for
unmarshalling a deviceinfo.

go.mod

@@ -6,6 +6,5 @@ require (
 	github.com/cavaliercoder/go-cpio v0.0.0-20180626203310-925f9528c45e
 	github.com/klauspost/compress v1.13.3 // indirect
 	github.com/klauspost/pgzip v1.2.5
-	github.com/pelletier/go-toml/v2 v2.0.0-beta.3
 	golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c
 )

go.sum

@@ -1,21 +1,9 @@
 github.com/cavaliercoder/go-cpio v0.0.0-20180626203310-925f9528c45e h1:hHg27A0RSSp2Om9lubZpiMgVbvn39bsUmW9U5h0twqc=
 github.com/cavaliercoder/go-cpio v0.0.0-20180626203310-925f9528c45e/go.mod h1:oDpT4efm8tSYHXV5tHSdRvBet/b/QzxZ+XyyPehvm3A=
-github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
-github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/golang/snappy v0.0.3/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
 github.com/klauspost/compress v1.13.3 h1:BtAvtV1+h0YwSVwWoYXMREPpYu9VzTJ9QDI1TEg/iQQ=
 github.com/klauspost/compress v1.13.3/go.mod h1:8dP1Hq4DHOhN9w426knH3Rhby4rFm6D8eO+e+Dq5Gzg=
 github.com/klauspost/pgzip v1.2.5 h1:qnWYvvKqedOF2ulHpMG72XQol4ILEJ8k2wwRl/Km8oE=
 github.com/klauspost/pgzip v1.2.5/go.mod h1:Ch1tH69qFZu15pkjo5kYi6mth2Zzwzt50oCQKQE9RUs=
-github.com/pelletier/go-toml/v2 v2.0.0-beta.3 h1:PNCTU4naEJ8mKal97P3A2qDU74QRQGlv4FXiL1XDqi4=
-github.com/pelletier/go-toml/v2 v2.0.0-beta.3/go.mod h1:aNseLYu/uKskg0zpr/kbr2z8yGuWtotWf/0BpGIAL2Y=
-github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
-github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.7.1-0.20210427113832-6241f9ab9942 h1:t0lM6y/M5IiUZyvbBTcngso8SZEZICH7is9B6g/obVU=
-github.com/stretchr/testify v1.7.1-0.20210427113832-6241f9ab9942/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c h1:F1jZWGFhYfh0Ci55sIpILtKKK8p3i2/krTr0H1rg74I=
 golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

main.go

@@ -29,14 +29,19 @@ func timeFunc(start time.Time, name string) {
 }
 
 func main() {
-	devinfo, err := deviceinfo.ReadDeviceinfo()
+	deviceinfoFile := "/etc/deviceinfo"
-	if err != nil {
+	if !exists(deviceinfoFile) {
 		log.Print("NOTE: deviceinfo (from device package) not installed yet, " +
 			"not building the initramfs now (it should get built later " +
 			"automatically.)")
 		return
 	}
 
+	devinfo, err := deviceinfo.ReadDeviceinfo(deviceinfoFile)
+	if err != nil {
+		log.Fatal(err)
+	}
+
 	outDir := flag.String("d", "/boot", "Directory to output initfs(-extra) and other boot files")
 	flag.Parse()
 

pkgs/deviceinfo/deviceinfo.go

@@ -4,59 +4,123 @@
 package deviceinfo
 
 import (
-	"errors"
+	"bufio"
-	toml "github.com/pelletier/go-toml/v2"
+	"fmt"
+	"io"
+	"log"
 	"os"
+	"reflect"
+	"strings"
 )
 
-// Note: fields must be exported (start with capital letter)
-// https://github.com/BurntSushi/toml/issues/121
 type DeviceInfo struct {
-	AppendDtb                     string `toml:"deviceinfo_append_dtb"`
+	AppendDtb                     string
-	Arch                          string `toml:"deviceinfo_arch"`
+	Arch                          string
-	BootimgAppendSEAndroidEnforce string `toml:"deviceinfo_bootimg_append_seandroidenforce"`
+	BootimgAppendSEAndroidEnforce string
-	BootimgBlobpack               string `toml:"deviceinfo_bootimg_blobpack"`
+	BootimgBlobpack               string
-	BootimgDtbSecond              string `toml:"deviceinfo_bootimg_dtb_second"`
+	BootimgDtbSecond              string
-	BootimgMtkMkimage             string `toml:"deviceinfo_bootimg_mtk_mkimage"`
+	BootimgMtkMkimage             string
-	BootimgPxa                    string `toml:"deviceinfo_bootimg_pxa"`
+	BootimgPxa                    string
-	BootimgQcdt                   string `toml:"deviceinfo_bootimg_qcdt"`
+	BootimgQcdt                   string
-	Dtb                           string `toml:"deviceinfo_dtb"`
+	Dtb                           string
-	FlashKernelOnUpdate           string `toml:"deviceinfo_flash_kernel_on_update"`
+	FlashKernelOnUpdate           string
-	FlashOffsetBase               string `toml:"deviceinfo_flash_offset_base"`
+	FlashOffsetBase               string
-	FlashOffsetKernel             string `toml:"deviceinfo_flash_offset_kernel"`
+	FlashOffsetKernel             string
-	FlashOffsetRamdisk            string `toml:"deviceinfo_flash_offset_ramdisk"`
+	FlashOffsetRamdisk            string
-	FlashOffsetSecond             string `toml:"deviceinfo_flash_offset_second"`
+	FlashOffsetSecond             string
-	FlashOffsetTags               string `toml:"deviceinfo_flash_offset_tags"`
+	FlashOffsetTags               string
-	FlashPagesize                 string `toml:"deviceinfo_flash_pagesize"`
+	FlashPagesize                 string
-	GenerateBootimg               string `toml:"deviceinfo_generate_bootimg"`
+	GenerateBootimg               string
-	GenerateLegacyUbootInitfs     string `toml:"deviceinfo_generate_legacy_uboot_initfs"`
+	GenerateLegacyUbootInitfs     string
-	InitfsCompression             string `toml:"deviceinfo_initfs_compression"`
+	InitfsCompression             string
-	KernelCmdline                 string `toml:"deviceinfo_kernel_cmdline"`
+	KernelCmdline                 string
-	LegacyUbootLoadAddress        string `toml:"deviceinfo_legacy_uboot_load_address"`
+	LegacyUbootLoadAddress        string
-	MesaDriver                    string `toml:"deviceinfo_mesa_driver"`
+	MesaDriver                    string
-	MkinitfsPostprocess           string `toml:"deviceinfo_mkinitfs_postprocess"`
+	MkinitfsPostprocess           string
-	ModulesInitfs                 string `toml:"deviceinfo_modules_initfs"`
+	ModulesInitfs                 string
 }
 
-func ReadDeviceinfo() (DeviceInfo, error) {
+func ReadDeviceinfo(file string) (DeviceInfo, error) {
-	file := "/etc/deviceinfo"
 	var deviceinfo DeviceInfo
 
-	_, err := os.Stat(file)
-	if err != nil {
-		return deviceinfo, errors.New("Unable to find deviceinfo: " + file)
-	}
-
 	fd, err := os.Open(file)
 	if err != nil {
 		return deviceinfo, err
 	}
 	defer fd.Close()
-	// contents,_ := toml.LoadFile(file)
+
-	decoder := toml.NewDecoder(fd)
+	if err := unmarshal(fd, &deviceinfo); err != nil {
-	if err := decoder.Decode(&deviceinfo); err != nil {
 		return deviceinfo, err
 	}
 
 	return deviceinfo, nil
 }
+
+// Unmarshals a deviceinfo into a DeviceInfo struct
+func unmarshal(r io.Reader, devinfo *DeviceInfo) error {
+	s := bufio.NewScanner(r)
+	for s.Scan() {
+		line := s.Text()
+		if strings.HasPrefix(line, "#") {
+			continue
+		}
+
+		// line isn't setting anything, so just ignore it
+		if !strings.Contains(line, "=") {
+			continue
+		}
+
+		// sometimes line has a comment at the end after setting an option
+		line = strings.SplitN(line, "#", 2)[0]
+		line = strings.TrimSpace(line)
+
+		// must support having '=' in the value (e.g. kernel cmdline)
+		parts := strings.SplitN(line, "=", 2)
+		if len(parts) != 2 {
+			return fmt.Errorf("error parsing deviceinfo line, invalid format: %s", line)
+		}
+
+		name, val := parts[0], parts[1]
+		val = strings.ReplaceAll(val, "\"", "")
+
+		if name == "deviceinfo_format_version" && val != "0" {
+			return fmt.Errorf("deviceinfo format version %q is not supported", val)
+		}
+
+		fieldName := nameToField(name)
+
+		if fieldName == "" {
+			return fmt.Errorf("error parsing deviceinfo line, invalid format: %s", line)
+		}
+
+		field := reflect.ValueOf(devinfo).Elem().FieldByName(fieldName)
+		if !field.IsValid() {
+			// an option that meets the deviceinfo "specification", but isn't
+			// one we care about in this module
+			continue
+		}
+		field.SetString(val)
+	}
+	if err := s.Err(); err != nil {
+		log.Print("unable to parse deviceinfo: ", err)
+		return err
+	}
+
+	return nil
+}
+
+// Convert string into the string format used for DeviceInfo fields.
+// Note: does not test that the resulting field name is a valid field in the
+// DeviceInfo struct!
+func nameToField(name string) string {
+	var field string
+	parts := strings.Split(name, "_")
+	for _, p := range parts {
+		if p == "deviceinfo" {
+			continue
+		}
+		field = field + strings.Title(p)
+	}
+
+	return field
+}