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46 | import { te, td, concat } from "./util";
export const FLUSH = te.encode("0000");
/** Encode one pkt-line (length prefix includes the 4 prefix bytes). */
export function pkt(payload: string | Uint8Array): Uint8Array {
const body = typeof payload === "string" ? te.encode(payload) : payload;
if (body.length > 65516) throw new Error("pkt-line too long");
return concat([te.encode((body.length + 4).toString(16).padStart(4, "0")), body]);
}
export function pktLines(...payloads: (string | Uint8Array)[]): Uint8Array {
return concat(payloads.map(pkt));
}
export type Pkt = { kind: "flush" | "delim" | "line"; raw: Uint8Array; text: string };
/** Iterates pkt-lines from a buffer; `rest()` returns unparsed bytes (e.g. a packfile). */
export class PktParser {
pos = 0;
constructor(private buf: Uint8Array) {}
read(): Pkt | null {
if (this.pos + 4 > this.buf.length) return null;
const len = parseInt(td.decode(this.buf.subarray(this.pos, this.pos + 4)), 16);
if (Number.isNaN(len)) throw new Error("bad pkt-line length");
if (len === 0) {
this.pos += 4;
return { kind: "flush", raw: new Uint8Array(0), text: "" };
}
if (len === 1) {
this.pos += 4;
return { kind: "delim", raw: new Uint8Array(0), text: "" };
}
if (len < 4 || this.pos + len > this.buf.length) throw new Error("bad pkt-line");
const raw = this.buf.subarray(this.pos + 4, this.pos + len);
this.pos += len;
let text = td.decode(raw);
if (text.endsWith("\n")) text = text.slice(0, -1);
return { kind: "line", raw, text };
}
rest(): Uint8Array {
return this.buf.subarray(this.pos);
}
}
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