import { assert } from "../_util/assert.ts";import type { BufReader } from "./buffer.ts";import type { Reader, Writer } from "./types.d.ts";import * as streams from "../streams/conversion.ts";import * as files from "./files.ts";
const DEFAULT_BUFFER_SIZE = 32 * 1024;
export async function copyN( r: Reader, dest: Writer, size: number,): Promise<number> { let bytesRead = 0; let buf = new Uint8Array(DEFAULT_BUFFER_SIZE); while (bytesRead < size) { if (size - bytesRead < DEFAULT_BUFFER_SIZE) { buf = new Uint8Array(size - bytesRead); } const result = await r.read(buf); const nread = result ?? 0; bytesRead += nread; if (nread > 0) { let n = 0; while (n < nread) { n += await dest.write(buf.slice(n, nread)); } assert(n === nread, "could not write"); } if (result === null) { break; } } return bytesRead;}
export async function readShort(buf: BufReader): Promise<number | null> { const high = await buf.readByte(); if (high === null) return null; const low = await buf.readByte(); if (low === null) throw new Deno.errors.UnexpectedEof(); return (high << 8) | low;}
export async function readInt(buf: BufReader): Promise<number | null> { const high = await readShort(buf); if (high === null) return null; const low = await readShort(buf); if (low === null) throw new Deno.errors.UnexpectedEof(); return (high << 16) | low;}
const MAX_SAFE_INTEGER = BigInt(Number.MAX_SAFE_INTEGER);
export async function readLong(buf: BufReader): Promise<number | null> { const high = await readInt(buf); if (high === null) return null; const low = await readInt(buf); if (low === null) throw new Deno.errors.UnexpectedEof(); const big = (BigInt(high) << 32n) | BigInt(low); if (big > MAX_SAFE_INTEGER) { throw new RangeError( "Long value too big to be represented as a JavaScript number.", ); } return Number(big);}
export function sliceLongToBytes( d: number, dest = Array.from<number>({ length: 8 }),): number[] { let big = BigInt(d); for (let i = 0; i < 8; i++) { dest[7 - i] = Number(big & 0xffn); big >>= 8n; } return dest;}
export const readAll = streams.readAll;export const readAllSync = streams.readAllSync;export const writeAll = streams.writeAll;export const writeAllSync = streams.writeAllSync;export const iter = streams.iterateReader;export const iterSync = streams.iterateReaderSync;export const copy = streams.copy;export const readRange = files.readRange;export const readRangeSync = files.readRangeSync;