Add null to terminate strings

pdu/submit.go

@@ -5,6 +5,8 @@ import (
 	"encoding/ascii85"
 	"encoding/binary"
 	"fmt"
+
+	"github.com/warthog618/sms/encoding/gsm7"
 )
 
 type (
@@ -69,32 +71,41 @@ func (p *SUBMIT_SM) Encode(buf *bytes.Buffer) error {
 	if buf == nil {
 		return fmt.Errorf("cannot encode into nil buffer")
 	}
+	asciiEncoder := ascii85.NewEncoder(buf)
+	// TODO: Implement encodings bsed on p.data_coding
+	messageEncoder := gsm7.NewEncoder()
+
 	p.header.Encode(buf)
-	n := ascii85.Encode(buf.Bytes(), []byte(p.service_type))
-	buf.Truncate(n)
+	asciiEncoder.Write([]byte(p.service_type))
+	buf.Write(NULL_ARR)
+	asciiEncoder.Write([]byte(p.service_type))
+	buf.Write(NULL_ARR)
 	binary.Write(buf, binary.BigEndian, p.source_addr_ton)
 	binary.Write(buf, binary.BigEndian, p.source_addr_npi)
-	n = ascii85.Encode(buf.Bytes(), []byte(p.source_addr))
-	buf.Truncate(n)
+	asciiEncoder.Write([]byte(p.source_addr))
+	buf.Write(NULL_ARR)
 	binary.Write(buf, binary.BigEndian, p.dest_addr_ton)
 	binary.Write(buf, binary.BigEndian, p.dest_addr_npi)
-	n = ascii85.Encode(buf.Bytes(), []byte(p.destination_addr))
-	buf.Truncate(n)
+	asciiEncoder.Write([]byte(p.destination_addr))
+	buf.Write(NULL_ARR)
 	binary.Write(buf, binary.BigEndian, p.esm_class)
 	binary.Write(buf, binary.BigEndian, p.protocol_id)
 	binary.Write(buf, binary.BigEndian, p.priority_flag)
-	n = ascii85.Encode(buf.Bytes(), []byte(p.schedule_delivery_time))
-	buf.Truncate(n)
-	n = ascii85.Encode(buf.Bytes(), []byte(p.validity_period))
-	buf.Truncate(n)
+	asciiEncoder.Write([]byte(p.schedule_delivery_time))
+	buf.Write(NULL_ARR)
+	asciiEncoder.Write([]byte(p.validity_period))
+	buf.Write(NULL_ARR)
 	binary.Write(buf, binary.BigEndian, p.registered_delivery)
 	binary.Write(buf, binary.BigEndian, p.replace_if_present)
 	binary.Write(buf, binary.BigEndian, p.data_coding)
 	binary.Write(buf, binary.BigEndian, p.sm_default_msg_id)
 	binary.Write(buf, binary.BigEndian, p.sm_length)
-	// TODO: Implement encodings bsed on p.data_coding
-	n = ascii85.Encode(buf.Bytes(), []byte(p.short_message))
-	buf.Truncate(n)
+	encodedMsg, err := messageEncoder.Encode([]byte(p.short_message))
+	if err != nil {
+		return err
+	}
+	buf.Write(encodedMsg)
+	buf.Write(NULL_ARR)
 	return nil
 }
 func (p *SUBMIT_SM) Decode(buf *bytes.Buffer) error {
@@ -106,23 +117,33 @@ func (p *SUBMIT_SM) Decode(buf *bytes.Buffer) error {
 func (p *SUBMIT_SM) Size() int {
 	var size int
 	size += p.header.Size()
-	size += len(p.service_type) * 1
+	size += 1 + len(p.service_type)
 	size += 1 // source_addr_ton
 	size += 1 // source_addr_npi
-	size += len(p.source_addr) * 1
+	size += 1 + len(p.source_addr)
 	size += 1 // dest_addr_ton
 	size += 1 // dest_addr_npi
-	size += len(p.destination_addr) * 1
+	size += 1 + len(p.destination_addr)
 	size += 1 // esm_class
 	size += 1 // protocol_id
 	size += 1 // priority_flag
-	size += len(p.schedule_delivery_time) * 1
-	size += len(p.validity_period) * 1
+	size += 1 + len(p.schedule_delivery_time)
+	size += 1 + len(p.validity_period)
 	size += 1 // registered_delivery
 	size += 1 // replace_if_present
 	size += 1 // data_coding
 	size += 1 // sm_default_msg_id
 	size += 1 // sm_length
-	size += len(p.short_message) * 1
+	// TODO: Handle encoding based on p.data_coding
+	switch p.data_coding {
+	case 0b00000000: // GSM7
+		size += (len(p.short_message)*7 + 8 - 1) / 8
+	case 0b00000001: // ASCII
+		size += len(p.short_message)
+	case 0b00000011: // LATIN1
+		size += len(p.short_message)
+	case 0b00001000: // UCS2
+		size += len(p.short_message) * 2
+	}
 	return size
 }