[VOL-3380] Functional area specific logging

Change-Id: I67414da013d8fc82827fcdb69d4f8a34040625d3
diff --git a/internal/pkg/common/utils.go b/internal/pkg/common/utils.go
new file mode 100755
index 0000000..8ea2624
--- /dev/null
+++ b/internal/pkg/common/utils.go
@@ -0,0 +1,155 @@
+/*
+ * Copyright 2020-present Open Networking Foundation
+ *
+ * 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 common provides global definitions
+package common
+
+import (
+	"bytes"
+	"context"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"net"
+	"regexp"
+	"strconv"
+	"strings"
+
+	"github.com/looplab/fsm"
+	me "github.com/opencord/omci-lib-go/generated"
+	"github.com/opencord/voltha-lib-go/v7/pkg/log"
+)
+
+// GetTpIDFromTpPath extracts TpID from the TpPath.
+// On success it returns a valid TpID and nil error.
+// On failure it returns TpID as 0 and the error.
+func GetTpIDFromTpPath(tpPath string) (uint8, error) {
+	// tpPath is of the format  <technology>/<table_id>/olt-{}/pon-{}/onu-{}/uni-{}
+	// A sample tpPath is ==> XGS-PON/64/olt-{12345abcd}/pon-{0}/onu-{1}/uni-{1}
+	var tpPathFormat = regexp.MustCompile(`^[a-zA-Z\-_]+/[0-9]+/olt-{[a-z0-9\-]+}/pon-{[0-9]+}/onu-{[0-9]+}/uni-{[0-9]+}$`)
+
+	// Ensure tpPath is of the format  <technology>/<table_id>/<uni_port_name>
+	if !tpPathFormat.Match([]byte(tpPath)) {
+		return 0, errors.New("tp-path-not-confirming-to-format")
+	}
+	// Extract the TP table-id field.
+	tpID, err := strconv.Atoi(strings.Split(tpPath, "/")[1])
+	// Atoi returns uint64 and need to be type-casted to uint8 as tpID is uint8 size.
+	return uint8(tpID), err
+}
+
+//IPToInt32 transforms an IP of net.Ip type to int32
+func IPToInt32(ip net.IP) uint32 {
+	if len(ip) == 16 {
+		return binary.BigEndian.Uint32(ip[12:16])
+	}
+	return binary.BigEndian.Uint32(ip)
+}
+
+//AsByteSlice transforms a string of manually set bits to a byt array
+func AsByteSlice(bitString string) []byte {
+	var out []byte
+	var str string
+
+	for i := len(bitString); i > 0; i -= 8 {
+		if i-8 < 0 {
+			str = bitString[0:i]
+		} else {
+			str = bitString[i-8 : i]
+		}
+		v, err := strconv.ParseUint(str, 2, 8)
+		if err != nil {
+			panic(err)
+		}
+		out = append([]byte{byte(v)}, out...)
+	}
+	return out
+}
+
+// TwosComplementToSignedInt16 convert 2s complement to signed int16
+func TwosComplementToSignedInt16(val uint16) int16 {
+	var uint16MsbMask uint16 = 0x8000
+	if val&uint16MsbMask == uint16MsbMask {
+		return int16(^val+1) * -1
+	}
+
+	return int16(val)
+}
+
+// TrimStringFromMeOctet trim string out of Me octet
+func TrimStringFromMeOctet(input interface{}) string {
+	ifBytes, _ := me.InterfaceToOctets(input)
+	return fmt.Sprintf("%s", bytes.Trim(ifBytes, "\x00"))
+}
+
+////////////////////////////////////////////////////////////////////////
+
+//NewAdapterFsm - FSM details including event, device and channel.
+func NewAdapterFsm(aName string, aDeviceID string, aCommChannel chan Message) *AdapterFsm {
+	aFsm := &AdapterFsm{
+		fsmName:  aName,
+		deviceID: aDeviceID,
+		CommChan: aCommChannel,
+	}
+	return aFsm
+}
+
+// LogFsmStateChange logs FSM state changes
+func (oo *AdapterFsm) LogFsmStateChange(ctx context.Context, e *fsm.Event) {
+	logger.Debugw(ctx, "FSM state change", log.Fields{"device-id": oo.deviceID, "FSM name": oo.fsmName,
+		"event name": string(e.Event), "src state": string(e.Src), "dst state": string(e.Dst)})
+}
+
+////////////////////////////////////////////////////////////////////////
+
+// GenerateIeeMaperServiceProfileEID returns IeeMaperServiceProfileEntityID
+func GenerateIeeMaperServiceProfileEID(uniPortMacBpNo uint16, tpID uint16) (uint16, error) {
+	if tpID < tpIDStart || tpID >= tpIDEnd {
+		return 0, fmt.Errorf("tech profile id out of range - %d", tpID)
+	}
+	if uniPortMacBpNo > maxUni {
+		return 0, fmt.Errorf("uni macbpno out of range - %d", uniPortMacBpNo)
+	}
+	return (IeeMaperServiceProfileBaseEID + uniPortMacBpNo*tpRange + tpID - tpIDStart), nil
+}
+
+// GenerateANISideMBPCDEID returns ANISideMacBridgePortConfigurationDataEntryID
+func GenerateANISideMBPCDEID(uniPortMacBpNo uint16, tpID uint16) (uint16, error) {
+	if tpID < tpIDStart || tpID >= tpIDEnd {
+		return 0, fmt.Errorf("tech profile id out of range - %d", tpID)
+	}
+	if uniPortMacBpNo > maxUni {
+		return 0, fmt.Errorf("uni macbpno out of range - %d", uniPortMacBpNo)
+	}
+	return (MacBridgePortAniBaseEID + uniPortMacBpNo*tpRange + tpID - tpIDStart), nil
+}
+
+// GenerateUNISideMBPCDEID returns UNISideMacBridgePortConfigurationDataEntityID
+func GenerateUNISideMBPCDEID(uniPortMacBpNo uint16) (uint16, error) {
+	if uniPortMacBpNo > maxUni {
+		return 0, fmt.Errorf("uni macbpno out of range - %d", uniPortMacBpNo)
+	}
+	return (MacBridgePortUniBaseEID + uniPortMacBpNo), nil
+}
+
+// GenerateMcastANISideMBPCDEID returns McastANISideMacBridgePortConfigurationDataEntityID
+func GenerateMcastANISideMBPCDEID(uniPortMacBpNo uint16) (uint16, error) {
+
+	if uniPortMacBpNo > maxUni {
+		return 0, fmt.Errorf("uni macbpno out of range - %d", uniPortMacBpNo)
+	}
+	return (MacBridgePortAniMcastBaseEID + uniPortMacBpNo), nil
+}