Fix Unity media stream lifetime leaks and add latest-frame video coalescing

Editor/IosLinkOrderDiagnostics.cs

@@ -0,0 +1,255 @@
+#if UNITY_EDITOR
+using System;
+using System.IO;
+using System.Collections.Generic;
+using System.Linq;
+using UnityEditor;
+using UnityEditor.Callbacks;
+using UnityEngine;
+using Process = System.Diagnostics.Process;
+using ProcessStartInfo = System.Diagnostics.ProcessStartInfo;
+
+public static class IosLinkOrderDiagnostics
+{
+    private const string Prefix = "LiveKit";
+    private const string Libilivekit = "liblivekit_ffi.a in Frameworks";
+    private const string Libiphone = "libiPhone-lib.a in Frameworks";
+    private static readonly string[] ConflictingLibiPhoneMembers =
+    {
+        "bands.o",
+        "celt.o",
+        "cwrs.o",
+        "entcode.o",
+        "entdec.o",
+        "entenc.o",
+        "header.o",
+        "kiss_fft.o",
+        "laplace.o",
+        "mathops.o",
+        "mdct-acf77e498fcf88b2edc7736c8f447bee8d7b174d050f1e9bd161576066636768.o",
+        "modes.o",
+        "pitch.o",
+        "plc.o",
+        "quant_bands.o",
+        "rate.o",
+        "vq.o",
+        "fmod_codec_celt.o"
+    };
+
+    [PostProcessBuild(999)]
+    public static void OnPostProcessBuild(BuildTarget target, string pathToBuiltProject)
+    {
+        if (target != BuildTarget.iOS)
+            return;
+
+        var projectPath = Path.Combine(pathToBuiltProject, "Unity-iPhone.xcodeproj", "project.pbxproj");
+        if (!File.Exists(projectPath))
+        {
+            Debug.LogWarning($"{Prefix}: iOS link-order diagnostic could not find {projectPath}");
+            return;
+        }
+
+        var projectText = File.ReadAllText(projectPath);
+        var fixedProjectText = EnsureSafeUnityFrameworkLinkOrder(projectText, out var wasModified);
+        if (wasModified)
+        {
+            File.WriteAllText(projectPath, fixedProjectText);
+            projectText = fixedProjectText;
+            Debug.Log($"{Prefix}: iOS link-order fix applied. Moved libiPhone-lib.a after liblivekit_ffi.a in UnityFramework -> Frameworks and Libraries.");
+        }
+
+        StripConflictingCodecObjects(pathToBuiltProject);
+
+        var frameworkSection = ExtractUnityFrameworkSection(projectText);
+        if (string.IsNullOrEmpty(frameworkSection))
+        {
+            Debug.LogWarning($"{Prefix}: iOS link-order diagnostic could not locate the UnityFramework frameworks section in the exported Xcode project.");
+            return;
+        }
+
+        var livekitIndex = frameworkSection.IndexOf(Libilivekit, StringComparison.Ordinal);
+        var iphoneIndex = frameworkSection.IndexOf(Libiphone, StringComparison.Ordinal);
+        if (livekitIndex < 0 || iphoneIndex < 0)
+        {
+            Debug.LogWarning($"{Prefix}: iOS link-order diagnostic could not locate both {Libilivekit} and {Libiphone} in UnityFramework -> Frameworks and Libraries.");
+            return;
+        }
+
+        if (livekitIndex < iphoneIndex)
+        {
+            Debug.Log($"{Prefix}: iOS link-order diagnostic OK. UnityFramework links liblivekit_ffi.a before libiPhone-lib.a.");
+            return;
+        }
+
+        Debug.LogWarning(
+            $"{Prefix}: iOS link-order diagnostic found a risky order in UnityFramework -> Frameworks and Libraries. " +
+            "libiPhone-lib.a appears before liblivekit_ffi.a. This repo documents that this can crash Opus/CELT on iOS. " +
+            "The post-process fix could not rewrite the exported project automatically."
+        );
+    }
+
+    private static string EnsureSafeUnityFrameworkLinkOrder(string projectText, out bool wasModified)
+    {
+        wasModified = false;
+
+        if (!TryGetUnityFrameworkSectionBounds(projectText, out var sectionStart, out var sectionEnd))
+            return projectText;
+
+        var frameworkSection = projectText.Substring(sectionStart, sectionEnd - sectionStart);
+        var livekitIndex = frameworkSection.IndexOf(Libilivekit, StringComparison.Ordinal);
+        var iphoneIndex = frameworkSection.IndexOf(Libiphone, StringComparison.Ordinal);
+        if (livekitIndex < 0 || iphoneIndex < 0 || livekitIndex < iphoneIndex)
+            return projectText;
+
+        var iphoneLineStart = frameworkSection.LastIndexOf('\n', iphoneIndex);
+        if (iphoneLineStart < 0)
+            iphoneLineStart = 0;
+        else
+            iphoneLineStart += 1;
+
+        var iphoneLineEnd = frameworkSection.IndexOf('\n', iphoneIndex);
+        if (iphoneLineEnd < 0)
+            iphoneLineEnd = frameworkSection.Length;
+        else
+            iphoneLineEnd += 1;
+
+        var iphoneLine = frameworkSection.Substring(iphoneLineStart, iphoneLineEnd - iphoneLineStart);
+        var sectionWithoutIphone = frameworkSection.Remove(iphoneLineStart, iphoneLineEnd - iphoneLineStart);
+
+        var livekitIndexAfterRemoval = sectionWithoutIphone.IndexOf(Libilivekit, StringComparison.Ordinal);
+        if (livekitIndexAfterRemoval < 0)
+            return projectText;
+
+        var insertIndex = sectionWithoutIphone.IndexOf('\n', livekitIndexAfterRemoval);
+        if (insertIndex < 0)
+            return projectText;
+
+        insertIndex += 1;
+        var reorderedSection = sectionWithoutIphone.Insert(insertIndex, iphoneLine);
+        wasModified = !string.Equals(frameworkSection, reorderedSection, StringComparison.Ordinal);
+        if (!wasModified)
+            return projectText;
+
+        return projectText.Substring(0, sectionStart) + reorderedSection + projectText.Substring(sectionEnd);
+    }
+
+    private static string ExtractUnityFrameworkSection(string projectText)
+    {
+        if (!TryGetUnityFrameworkSectionBounds(projectText, out var sectionStart, out var sectionEnd))
+            return string.Empty;
+
+        return projectText.Substring(sectionStart, sectionEnd - sectionStart);
+    }
+
+    private static bool TryGetUnityFrameworkSectionBounds(string projectText, out int sectionStart, out int sectionEnd)
+    {
+        sectionStart = -1;
+        sectionEnd = -1;
+
+        const string marker = "/* UnityFramework */ = {\n\t\t\tisa = PBXFrameworksBuildPhase;";
+        var markerIndex = projectText.IndexOf(marker, StringComparison.Ordinal);
+        if (markerIndex < 0)
+            return false;
+
+        var filesIndex = projectText.IndexOf("\t\t\tfiles = (", markerIndex, StringComparison.Ordinal);
+        if (filesIndex < 0)
+            return false;
+
+        var endIndex = projectText.IndexOf("\t\t\t);", filesIndex, StringComparison.Ordinal);
+        if (endIndex < 0)
+            return false;
+
+        sectionStart = filesIndex;
+        sectionEnd = endIndex;
+        return true;
+    }
+
+    private static void StripConflictingCodecObjects(string pathToBuiltProject)
+    {
+        var archivePath = Path.Combine(pathToBuiltProject, "Libraries", "libiPhone-lib.a");
+        if (!File.Exists(archivePath))
+        {
+            Debug.Log($"{Prefix}: iOS archive fix skipped because {archivePath} was not found.");
+            return;
+        }
+
+        if (!TryRunProcess("/usr/bin/ar", $" -t \"{archivePath}\"", out var memberOutput, out var listError))
+        {
+            Debug.LogWarning($"{Prefix}: iOS archive fix could not inspect libiPhone-lib.a members. {listError}");
+            return;
+        }
+
+        var members = new HashSet<string>(
+            memberOutput
+                .Split(new[] { '\r', '\n' }, StringSplitOptions.RemoveEmptyEntries)
+                .Select(line => line.Trim()),
+            StringComparer.Ordinal
+        );
+
+        var membersToRemove = ConflictingLibiPhoneMembers.Where(members.Contains).ToArray();
+        if (membersToRemove.Length == 0)
+        {
+            Debug.Log($"{Prefix}: iOS archive fix found no conflicting CELT objects in libiPhone-lib.a.");
+            return;
+        }
+
+        var deleteArguments = $" -d \"{archivePath}\" {string.Join(" ", membersToRemove.Select(QuoteArgument))}";
+        if (!TryRunProcess("/usr/bin/ar", deleteArguments, out _, out var deleteError))
+        {
+            Debug.LogWarning($"{Prefix}: iOS archive fix could not strip conflicting objects from libiPhone-lib.a. {deleteError}");
+            return;
+        }
+
+        if (!TryRunProcess("/usr/bin/ranlib", $" \"{archivePath}\"", out _, out var ranlibError))
+        {
+            Debug.LogWarning($"{Prefix}: iOS archive fix stripped conflicting objects but ranlib failed. {ranlibError}");
+            return;
+        }
+
+        Debug.Log($"{Prefix}: iOS archive fix stripped {membersToRemove.Length} conflicting CELT objects from exported libiPhone-lib.a.");
+    }
+
+    private static bool TryRunProcess(string fileName, string arguments, out string stdout, out string error)
+    {
+        stdout = string.Empty;
+        error = string.Empty;
+
+        try
+        {
+            using var process = new Process();
+            process.StartInfo = new ProcessStartInfo
+            {
+                FileName = fileName,
+                Arguments = arguments,
+                RedirectStandardOutput = true,
+                RedirectStandardError = true,
+                UseShellExecute = false,
+                CreateNoWindow = true
+            };
+
+            process.Start();
+            stdout = process.StandardOutput.ReadToEnd();
+            var stderr = process.StandardError.ReadToEnd();
+            process.WaitForExit();
+
+            if (process.ExitCode == 0)
+                return true;
+
+            error = string.IsNullOrWhiteSpace(stderr)
+                ? $"{fileName} exited with code {process.ExitCode}."
+                : stderr.Trim();
+            return false;
+        }
+        catch (Exception ex)
+        {
+            error = ex.Message;
+            return false;
+        }
+    }
+
+    private static string QuoteArgument(string value)
+    {
+        return $"\"{value.Replace("\"", "\\\"")}\"";
+    }
+}
+#endif

README.md

@@ -97,9 +97,13 @@ add other linker flags to `UnityFramework`:
 
 `-ObjC`
 
-Since `libiPhone-lib.a` has built-in old versions of `celt` and `libvpx` (This will cause the opus and vp8/vp9 codecs to not be called correctly and cause a crash.), so you need to adjust the link order to ensure that it is linked to `liblivekit_ffi.a` first.
+Since `libiPhone-lib.a` has built-in old versions of `celt` and `libvpx` (This will cause the opus and vp8/vp9 codecs to not be called correctly and cause a crash.), you need to ensure that `liblivekit_ffi.a` is linked before `libiPhone-lib.a`.
 
-The fix is ​​to remove and re-add `libiPhone-lib.a` from `Frameworks and Libraries`, making sure to link after `liblivekit_ffi.a`.
+The package now applies an iOS post-build fix that rewrites the exported Xcode project so `libiPhone-lib.a` is moved after `liblivekit_ffi.a` in `UnityFramework -> Frameworks and Libraries`.
+
+It also strips the old CELT object cluster from the exported `Libraries/libiPhone-lib.a` so Xcode cannot resolve those codec symbols from Unity's archive.
+
+If your project disables package editor scripts or uses a custom Xcode export pipeline that overwrites `project.pbxproj` after LiveKit runs, you may still need to adjust the order manually by removing and re-adding `libiPhone-lib.a`.
 
 ## Examples
 

Runtime/Scripts/AudioFrame.cs

@@ -57,8 +57,10 @@ protected virtual void Dispose(bool disposing)
                 {
                     _allocatedData.Dispose();
                 }
+
+                _handle?.Dispose();
                 _disposed = true;
             }
         }
     }
-}
+}