Merge pull request #503 from Icinga/parseString-DRY

parseString(): Don't Repeat Yourself

Author: Al2Klimov

go.mod

@@ -16,7 +16,7 @@ require (
 	github.com/ssgreg/journald v1.0.0
 	github.com/stretchr/testify v1.8.0
 	go.uber.org/zap v1.21.0
-	golang.org/x/exp v0.0.0-20210514180818-737f94c0881e
+	golang.org/x/exp v0.0.0-20220613132600-b0d781184e0d
 	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c
 )
 

go.sum

@@ -80,8 +80,8 @@ golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACk
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9 h1:psW17arqaxU48Z5kZ0CQnkZWQJsqcURM6tKiBApRjXI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/exp v0.0.0-20210514180818-737f94c0881e h1:VqVU3dsTLGDa5pW74b+xG1lvKltt4EZIUrFPeKOqV2s=
-golang.org/x/exp v0.0.0-20210514180818-737f94c0881e/go.mod h1:MSdmUWF4ZWBPSUbgUX/gaau5kvnbkSs9pgtY6B9JXDE=
+golang.org/x/exp v0.0.0-20220613132600-b0d781184e0d h1:vtUKgx8dahOomfFzLREU8nSv25YHnTgLBn4rDnWZdU0=
+golang.org/x/exp v0.0.0-20220613132600-b0d781184e0d/go.mod h1:Kr81I6Kryrl9sr8s2FK3vxD90NdsKWRuOIl2O4CvYbA=
 golang.org/x/lint v0.0.0-20190930215403-16217165b5de/go.mod h1:6SW0HCj/g11FgYtHlgUYUwCkIfeOF89ocIRzGO/8vkc=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=

pkg/structify/structify.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"github.com/icinga/icingadb/pkg/contracts"
 	"github.com/pkg/errors"
+	"golang.org/x/exp/constraints"
 	"reflect"
 	"strconv"
 	"strings"
@@ -118,66 +119,61 @@ func parseString(src string, dest interface{}) error {
 		*ptr = &src
 		return nil
 	case *uint8:
-		i, err := strconv.ParseUint(src, 10, int(unsafe.Sizeof(*ptr)*8))
-		if err == nil {
-			*ptr = uint8(i)
-		}
-		return err
+		return parseUint(src, ptr)
 	case *uint16:
-		i, err := strconv.ParseUint(src, 10, int(unsafe.Sizeof(*ptr)*8))
-		if err == nil {
-			*ptr = uint16(i)
-		}
-		return err
+		return parseUint(src, ptr)
 	case *uint32:
-		i, err := strconv.ParseUint(src, 10, int(unsafe.Sizeof(*ptr)*8))
-		if err == nil {
-			*ptr = uint32(i)
-		}
-		return err
+		return parseUint(src, ptr)
 	case *uint64:
-		i, err := strconv.ParseUint(src, 10, int(unsafe.Sizeof(*ptr)*8))
-		if err == nil {
-			*ptr = i
-		}
-		return err
+		return parseUint(src, ptr)
 	case *int8:
-		i, err := strconv.ParseInt(src, 10, int(unsafe.Sizeof(*ptr)*8))
-		if err == nil {
-			*ptr = int8(i)
-		}
-		return err
+		return parseInt(src, ptr)
 	case *int16:
-		i, err := strconv.ParseInt(src, 10, int(unsafe.Sizeof(*ptr)*8))
-		if err == nil {
-			*ptr = int16(i)
-		}
-		return err
+		return parseInt(src, ptr)
 	case *int32:
-		i, err := strconv.ParseInt(src, 10, int(unsafe.Sizeof(*ptr)*8))
-		if err == nil {
-			*ptr = int32(i)
-		}
-		return err
+		return parseInt(src, ptr)
 	case *int64:
-		i, err := strconv.ParseInt(src, 10, int(unsafe.Sizeof(*ptr)*8))
-		if err == nil {
-			*ptr = i
-		}
-		return err
+		return parseInt(src, ptr)
 	case *float32:
-		f, err := strconv.ParseFloat(src, int(unsafe.Sizeof(*ptr)*8))
-		if err == nil {
-			*ptr = float32(f)
-		}
-		return err
+		return parseFloat(src, ptr)
 	case *float64:
-		f, err := strconv.ParseFloat(src, int(unsafe.Sizeof(*ptr)*8))
-		if err == nil {
-			*ptr = f
-		}
-		return err
+		return parseFloat(src, ptr)
 	default:
 		panic(fmt.Sprintf("unsupported type: %T", dest))
 	}
 }
+
+// parseUint parses src into *dest.
+func parseUint[T constraints.Unsigned](src string, dest *T) error {
+	i, err := strconv.ParseUint(src, 10, bitSizeOf[T]())
+	if err == nil {
+		*dest = T(i)
+	}
+
+	return err
+}
+
+// parseInt parses src into *dest.
+func parseInt[T constraints.Signed](src string, dest *T) error {
+	i, err := strconv.ParseInt(src, 10, bitSizeOf[T]())
+	if err == nil {
+		*dest = T(i)
+	}
+
+	return err
+}
+
+// parseFloat parses src into *dest.
+func parseFloat[T constraints.Float](src string, dest *T) error {
+	f, err := strconv.ParseFloat(src, bitSizeOf[T]())
+	if err == nil {
+		*dest = T(f)
+	}
+
+	return err
+}
+
+func bitSizeOf[T any]() int {
+	var x T
+	return int(unsafe.Sizeof(x) * 8)
+}