fix: two long-running HLS transcode issues (#355)

* fix: release targets from Output._targets on finalize

Long-running HLS transcodes leak memory. Every finalized BufferTarget
stays in _targets until the outer Output closes, pinning its buffer.
Writer.finalize() already does this cleanup for writer-based flows;
extend it to buffer-finalize paths via the public 'finalized' event.

* fix: ReadOrchestrator LRU eviction picks only drained workers

assert(pendingSlices.length === 0) fires under heavy concurrent reads
(e.g. multi-rendition HLS decode from BlobSource). LRU filter only
checked !running; workers with queued slices could be evicted.
Add pendingSlices.length === 0 to the filter.

* fix: export AppendOnlyStreamTarget from index

Missing from the re-export; public docs import it by name.

* fix: join HLS init segment path with root + playlist path

Init path went through _getTarget bare; segments got joined with rootPath + playlist.path. Playlist-relative URI then can't resolve when the playlist lives in a subdirectory.

* Fix targets not being cleaned up, fix paused workers with remaining pending slices, modify doc block, fixed isRoot not being changed on proxied requests

---------

Co-authored-by: Vanilagy <[email protected]>

src/hls/hls-muxer.ts

@@ -898,6 +898,11 @@ export class HlsMuxer extends Muxer {
 				target: new PathedTarget(
 					fullSegmentPath,
 					async (request: TargetRequest) => {
+						const proxiedRequest: TargetRequest = {
+							...request,
+							isRoot: false,
+						};
+
 						if (request.isRoot) {
 							if (playlist.singleFile) {
 								const slice = playlist.singleFile.target.slice(playlist.singleFile.nextOffset);
@@ -905,7 +910,7 @@ export class HlsMuxer extends Muxer {
 
 								return slice;
 							} else {
-								const target = await this.output._getTarget(request);
+								const target = await this.output._getTarget(proxiedRequest);
 								outputTarget = target;
 								target.on('write', ({ end }) => segmentSize = Math.max(segmentSize, end));
 
@@ -913,7 +918,7 @@ export class HlsMuxer extends Muxer {
 							}
 						}
 
-						return this.output._getTarget(request);
+						return this.output._getTarget(proxiedRequest);
 					},
 				),
 				initTarget: async () => {
@@ -955,8 +960,12 @@ export class HlsMuxer extends Muxer {
 							info: null,
 						};
 
+						const fullInitPath = joinPaths(
+							joinPaths(pathedTarget.rootPath, playlist.path),
+							initPath,
+						);
 						const target = await this.output._getTarget({
-							path: initPath,
+							path: fullInitPath,
 							isRoot: false,
 							mimeType: playlist.segmentFormat.mimeType,
 						});

src/hls/hls-segmented-input.ts

@@ -11,7 +11,7 @@ import { ENCRYPTION_KEY_CACHE_GROUP, Input } from '../input';
 import { Segment, SegmentedInput, SegmentedInputTrackDeclaration, SegmentRetrievalOptions } from '../segmented-input';
 import { toDataView, joinPaths, last, assert, binarySearchLessOrEqual, arrayArgmin, wait } from '../misc';
 import { readAllLines, readBytes, Reader } from '../reader';
-import { CustomPathedSource, ReadableStreamSource, SourceRef } from '../source';
+import { CustomPathedSource, ReadableStreamSource, SourceRef, SourceRequest } from '../source';
 import { HlsDemuxer } from './hls-demuxer';
 import {
 	AttributeList,
@@ -568,6 +568,11 @@ export class HlsSegmentedInput extends SegmentedInput {
 				async (request) => {
 					assert(request.isRoot); // Shouldn't fail since we don't allow recursive HLS
 
+					const proxiedRequest: SourceRequest = {
+						...request,
+						isRoot: false,
+					};
+
 					let ref: SourceRef;
 					const needsSlice = hlsSegment.location.offset > 0 || hlsSegment.location.length !== null;
 
@@ -576,7 +581,7 @@ export class HlsSegmentedInput extends SegmentedInput {
 						|| hlsSegment.encryption.method === 'SAMPLE-AES'
 						|| hlsSegment.encryption.method === 'SAMPLE-AES-CTR'
 					) {
-						ref = await this.input._getSourceCached(request);
+						ref = await this.input._getSourceCached(proxiedRequest);
 
 						if (needsSlice) {
 							const slice = ref.source.slice(
@@ -591,7 +596,7 @@ export class HlsSegmentedInput extends SegmentedInput {
 						const encryption = hlsSegment.encryption;
 						assert(encryption.iv);
 
-						let ciphertextRef = await this.input._getSourceCached(request);
+						let ciphertextRef = await this.input._getSourceCached(proxiedRequest);
 						if (needsSlice) {
 							// Slice before decrypting
 							const slice = ciphertextRef.source.slice(