using System; using System.Globalization; using System.IO; using System.Threading; using System.Threading.Tasks; using MediaBrowser.Model.IO; using Microsoft.Extensions.Logging; namespace Jellyfin.Api.Helpers { /// <summary> /// The hls helpers. /// </summary> public static class HlsHelpers { /// <summary> /// Waits for a minimum number of segments to be available. /// </summary> /// <param name="playlist">The playlist string.</param> /// <param name="segmentCount">The segment count.</param> /// <param name="logger">Instance of the <see cref="ILogger"/> interface.</param> /// <param name="cancellationToken">The <see cref="CancellationToken"/>.</param> /// <returns>A <see cref="Task"/> indicating the waiting process.</returns> public static async Task WaitForMinimumSegmentCount(string playlist, int? segmentCount, ILogger logger, CancellationToken cancellationToken) { logger.LogDebug("Waiting for {0} segments in {1}", segmentCount, playlist); while (!cancellationToken.IsCancellationRequested) { try { // Need to use FileShare.ReadWrite because we're reading the file at the same time it's being written var fileStream = new FileStream( playlist, FileMode.Open, FileAccess.Read, FileShare.ReadWrite, IODefaults.FileStreamBufferSize, FileOptions.SequentialScan); await using (fileStream.ConfigureAwait(false)) { using var reader = new StreamReader(fileStream); var count = 0; while (!reader.EndOfStream) { var line = await reader.ReadLineAsync().ConfigureAwait(false); if (line == null) { // Nothing currently in buffer. break; } if (line.IndexOf("#EXTINF:", StringComparison.OrdinalIgnoreCase) != -1) { count++; if (count >= segmentCount) { logger.LogDebug("Finished waiting for {0} segments in {1}", segmentCount, playlist); return; } } } } await Task.Delay(100, cancellationToken).ConfigureAwait(false); } catch (IOException) { // May get an error if the file is locked } await Task.Delay(50, cancellationToken).ConfigureAwait(false); } } /// <summary> /// Gets the hls playlist text. /// </summary> /// <param name="path">The path to the playlist file.</param> /// <param name="segmentLength">The segment length.</param> /// <returns>The playlist text as a string.</returns> public static string GetLivePlaylistText(string path, int segmentLength) { using var stream = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite); using var reader = new StreamReader(stream); var text = reader.ReadToEnd(); text = text.Replace("#EXTM3U", "#EXTM3U\n#EXT-X-PLAYLIST-TYPE:EVENT", StringComparison.InvariantCulture); var newDuration = "#EXT-X-TARGETDURATION:" + segmentLength.ToString(CultureInfo.InvariantCulture); text = text.Replace("#EXT-X-TARGETDURATION:" + (segmentLength - 1).ToString(CultureInfo.InvariantCulture), newDuration, StringComparison.OrdinalIgnoreCase); // text = text.Replace("#EXT-X-TARGETDURATION:" + (segmentLength + 1).ToString(CultureInfo.InvariantCulture), newDuration, StringComparison.OrdinalIgnoreCase); return text; } } }