Release Archive Tools 0.1.0

src/archive/limits.ts

@@ -0,0 +1,59 @@
+import { ArchivePolicyError } from "./errors";
+
+export const ARCHIVE_LIMITS = Object.freeze({
+  maxSourceBytes: 512 * 1024 * 1024,
+  maxEntries: 20_000,
+  maxDisplayedEntries: 5_000,
+  maxExpandedBytes: 512 * 1024 * 1024,
+  maxEntryBytes: 256 * 1024 * 1024,
+  maxCompressionRatio: 200,
+  maxPathBytes: 4_096,
+  maxPathSegments: 64,
+  maxSegmentBytes: 255,
+  maxPreviewTextBytes: 2 * 1024 * 1024,
+  maxPreviewHexBytes: 128 * 1024,
+  maxPreviewImageBytes: 24 * 1024 * 1024,
+  maxPreviewImagePixels: 40_000_000,
+  maxPreviewImageEdge: 32_768,
+  maxCreateFiles: 5_000,
+  maxCreateBytes: 512 * 1024 * 1024,
+  maxPaxHeaderBytes: 1024 * 1024,
+});
+
+export function assertFiniteSafeInteger(value: number, label: string): void {
+  if (!Number.isSafeInteger(value) || value < 0) {
+    throw new ArchivePolicyError(
+      "INVALID_SIZE",
+      `${label} is not a safe non-negative byte count.`,
+    );
+  }
+}
+
+export function assertSourceSize(file: Blob): void {
+  if (file.size > ARCHIVE_LIMITS.maxSourceBytes) {
+    throw new ArchivePolicyError(
+      "SOURCE_TOO_LARGE",
+      `Archive exceeds the ${formatBytes(ARCHIVE_LIMITS.maxSourceBytes)} source limit.`,
+    );
+  }
+}
+
+export function formatBytes(bytes: number): string {
+  if (!Number.isFinite(bytes)) return "unknown";
+  const units = ["B", "KiB", "MiB", "GiB"];
+  let value = Math.max(0, bytes);
+  let unit = 0;
+  while (value >= 1024 && unit < units.length - 1) {
+    value /= 1024;
+    unit += 1;
+  }
+  return `${value >= 10 || unit === 0 ? value.toFixed(0) : value.toFixed(1)} ${units[unit]}`;
+}
+
+export function throwIfAborted(signal?: AbortSignal): void {
+  if (signal?.aborted) {
+    throw signal.reason instanceof Error
+      ? signal.reason
+      : new DOMException("Operation cancelled.", "AbortError");
+  }
+}