Revision control
Copy as Markdown
Other Tools
import { ViewWriter } from "./ViewWriter";
import { ValueBlock, ValueBlockJson } from "./ValueBlock";
import { BaseBlock, BaseBlockJson, BaseBlockParams } from "./BaseBlock";
import { typeStore } from "./TypeStore";
export type NullParams = BaseBlockParams;
export type NullJson = BaseBlockJson<ValueBlockJson>;
export class Null extends BaseBlock<ValueBlock, ValueBlockJson> {
static {
typeStore.Null = this;
}
public static override NAME = "NULL";
constructor(parameters: NullParams = {}) {
super(parameters, ValueBlock); // We will not have a call to "Null value block" because of specified FROM_BER and TO_BER functions
this.idBlock.tagClass = 1; // UNIVERSAL
this.idBlock.tagNumber = 5; // Null
}
public override fromBER(inputBuffer: ArrayBuffer | Uint8Array, inputOffset: number, inputLength: number): number {
if (this.lenBlock.length > 0)
this.warnings.push("Non-zero length of value block for Null type");
if (!this.idBlock.error.length)
this.blockLength += this.idBlock.blockLength;
if (!this.lenBlock.error.length)
this.blockLength += this.lenBlock.blockLength;
this.blockLength += inputLength;
if ((inputOffset + inputLength) > inputBuffer.byteLength) {
this.error = "End of input reached before message was fully decoded (inconsistent offset and length values)";
return -1;
}
return (inputOffset + inputLength);
}
public override toBER(sizeOnly?: boolean, writer?: ViewWriter): ArrayBuffer {
const retBuf = new ArrayBuffer(2);
if (!sizeOnly) {
const retView = new Uint8Array(retBuf);
retView[0] = 0x05;
retView[1] = 0x00;
}
if (writer) {
writer.write(retBuf);
}
return retBuf;
}
protected override onAsciiEncoding(): string {
return `${(this.constructor as typeof Null).NAME}`;
}
}