Preserve compact distribution notices and upstream copyright metadata

CREDITS.md

@@ -1,7 +1,9 @@
 # Contributors
 
-- Peter Sharma and contributors: application and controller protocol implementation.
+- [Peter Sharma and contributors](https://github.com/Peterksharma/switch2mac): application and controller protocol implementation.
 - Andrei-Kondrykau: browser integration.
 - vialoh: RetroArch integration.
 - ndeadly, Nadeflore, coffincolors, trevlars, darthcloud, and the controller research community: protocol research.
 - Sam Lantinga and the SDL contributors: SDL.
+
+License notices: [LICENSES/README.md](LICENSES/README.md).

Integrations/CMake/Bundle.cmake

@@ -22,13 +22,22 @@ function(switch2kit_embed target)
     set_property(TARGET "${target}" PROPERTY MACOSX_BUNDLE_INFO_PLIST "${_prepared}")
   endif()
 
+  get_filename_component(_notice_root "${CMAKE_CURRENT_FUNCTION_LIST_DIR}/../.." ABSOLUTE)
+  file(GLOB _notices CONFIGURE_DEPENDS "${_notice_root}/LICENSES/*")
+  set_property(TARGET "${target}" APPEND PROPERTY LINK_DEPENDS "${_notice_root}/CREDITS.md" ${_notices})
   add_custom_command(TARGET "${target}" POST_BUILD
     COMMAND "${CMAKE_COMMAND}" -E make_directory "$<TARGET_BUNDLE_CONTENT_DIR:${target}>/Frameworks"
     COMMAND "${CMAKE_COMMAND}" -E copy_if_different "$<TARGET_FILE:Switch2Kit::C>"
       "$<TARGET_BUNDLE_CONTENT_DIR:${target}>/Frameworks/"
     COMMAND "${CMAKE_COMMAND}"
       "-DS2K_BUNDLE_LIBRARY=$<TARGET_BUNDLE_CONTENT_DIR:${target}>/Frameworks/$<TARGET_FILE_NAME:Switch2Kit::C>"
       -P "${CMAKE_CURRENT_FUNCTION_LIST_DIR}/PrepareBundle.cmake"
+    COMMAND "${CMAKE_COMMAND}" -E make_directory
+      "$<TARGET_BUNDLE_CONTENT_DIR:${target}>/Resources/Switch2KitNotices"
+    COMMAND "${CMAKE_COMMAND}" -E copy_if_different "${_notice_root}/CREDITS.md"
+      "$<TARGET_BUNDLE_CONTENT_DIR:${target}>/Resources/Switch2KitNotices/CREDITS.md"
+    COMMAND "${CMAKE_COMMAND}" -E copy_directory "${_notice_root}/LICENSES"
+      "$<TARGET_BUNDLE_CONTENT_DIR:${target}>/Resources/Switch2KitNotices/LICENSES"
     COMMAND xcrun swift-stdlib-tool --copy --platform macosx
       --scan-executable "$<TARGET_FILE:Switch2Kit::C>"
       --destination "$<TARGET_BUNDLE_CONTENT_DIR:${target}>/Frameworks"

LICENSES/MIT-trevlars.txt

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 trevlars
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

LICENSES/README.md

@@ -0,0 +1,8 @@
+# Third-party notices
+
+Switch2Kit includes code from [Peterksharma/switch2mac](https://github.com/Peterksharma/switch2mac/tree/ea6719f0a1d6b6986c00aca9ed4169a85c8cc9ae). Contributors are listed in [CREDITS.md](../CREDITS.md).
+
+- [MIT-trevlars.txt](MIT-trevlars.txt): controller reference implementation, [trevlars/switch2-controllers-linux](https://github.com/trevlars/switch2-controllers-linux).
+- [SDL-zlib.txt](SDL-zlib.txt): SDL-derived patches, [SDL 3.4.14](https://github.com/libsdl-org/SDL/tree/147a8ee32dbf9ac02f3794964490687b6bbda1bc). These are modified, unofficial SDL sources.
+
+Dolphin and Cemu retain their upstream copyright and license notices.

LICENSES/SDL-zlib.txt

@@ -0,0 +1,17 @@
+Copyright (C) 1997-2026 Sam Lantinga <slouken@libsdl.org>
+
+This software is provided 'as-is', without any express or implied
+warranty.  In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not
+   claim that you wrote the original software. If you use this software
+   in a product, an acknowledgment in the product documentation would be
+   appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.

Resources/Info.plist

@@ -23,6 +23,6 @@
     <key>NSBluetoothAlwaysUsageDescription</key>
     <string>Switch2Kit talks to your Nintendo Switch 2 controllers over Bluetooth so games on this Mac can use them.</string>
     <key>NSHumanReadableCopyright</key>
-    <string>© 2026 Peter Sharma. Protocol research by the Switch 2 controller community.</string>
+    <string>© 2026 Peter Sharma and Switch2Kit contributors.</string>
 </dict>
 </plist>

scripts/build-app.sh

@@ -41,12 +41,17 @@ if [ -f Resources/AppIcon.icns ]; then
         "$OUT/Contents/Info.plist" 2>/dev/null || true
 fi
 
+# Keep the compact source notices in the bundle before any signature is applied.
+mkdir -p "$OUT/Contents/Resources/Switch2KitNotices"
+cp CREDITS.md "$OUT/Contents/Resources/Switch2KitNotices/"
+cp -R LICENSES "$OUT/Contents/Resources/Switch2KitNotices/"
+
 # Keep setup resources with the binary; never install the extension automatically.
 mkdir -p "$OUT/Contents/Resources/BrowserExtension"
 cp browser/extension/manifest.json browser/extension/*.js "$OUT/Contents/Resources/BrowserExtension/"
 REVISION=$(git rev-parse HEAD)
 DIRTY=false
-[ -z "$(git status --porcelain --untracked-files=normal -- Sources Resources browser/extension scripts Package.swift)" ] || DIRTY=true
+[ -z "$(git status --porcelain --untracked-files=normal -- Sources Resources browser/extension scripts Package.swift CREDITS.md LICENSES)" ] || DIRTY=true
 /usr/libexec/PlistBuddy -c "Add :Switch2KitSourceRevision string $REVISION" "$OUT/Contents/Info.plist"
 /usr/libexec/PlistBuddy -c "Add :Switch2KitSourceDirty bool $DIRTY" "$OUT/Contents/Info.plist"
 /usr/libexec/PlistBuddy -c "Add :Switch2KitBuildArchitecture string $(uname -m)" "$OUT/Contents/Info.plist"

scripts/build-switch2kit-c.sh

@@ -60,6 +60,9 @@ lipo "$WORK/consumer" -verify_arch arm64 x86_64
 "$WORK/consumer"
 xcodebuild -create-xcframework -library "$LIB" \
   -headers "$ROOT/Sources/Switch2KitCABI/include" -output "$WORK/Switch2KitC.xcframework"
+mkdir -p "$WORK/Switch2KitC.xcframework/Notices"
+cp "$ROOT/CREDITS.md" "$WORK/Switch2KitC.xcframework/Notices/"
+cp -R "$ROOT/LICENSES" "$WORK/Switch2KitC.xcframework/Notices/"
 plutil -lint "$WORK/Switch2KitC.xcframework/Info.plist"
 python3 - "$WORK/Switch2KitC.xcframework/Info.plist" <<'PY'
 import plistlib,sys

scripts/build-switch2kit-emulator.sh

@@ -17,3 +17,4 @@ case "$emulator" in
 esac
 cmake -S "$source" -B "$build" "${args[@]}" "$@"
 cmake --build "$build" --target "$target" --parallel "${S2K_BUILD_JOBS:-4}"
+python3 "$root/scripts/verify-distribution-notices.py" "$emulator" "$source" "$build"

scripts/verify-distribution-notices.py

@@ -0,0 +1,52 @@
+#!/usr/bin/env python3
+"""Check bundled source notices and upstream Finder metadata."""
+import argparse
+import hashlib
+import json
+from pathlib import Path
+import plistlib
+
+ROOT = Path(__file__).resolve().parents[1]
+NOTICES = ('CREDITS.md', 'LICENSES/README.md', 'LICENSES/MIT-trevlars.txt', 'LICENSES/SDL-zlib.txt')
+
+
+def verify(app, emulator, root=ROOT):
+    info = plistlib.loads((app / 'Contents/Info.plist').read_bytes())
+    expected_id = {'dolphin': 'org.dolphin-emu.dolphin', 'cemu': 'info.cemu.Cemu'}[emulator]
+    if info.get('CFBundleIdentifier') != expected_id:
+        raise ValueError('Unexpected host bundle identifier')
+    notice = info.get('NSHumanReadableCopyright')
+    if not isinstance(notice, str) or not notice.strip() or not (
+            'GPL' in notice if emulator == 'dolphin' else 'Cemu' in notice):
+        raise ValueError('Missing or replaced upstream Finder copyright/license notice')
+    digests = {}
+    for name in NOTICES:
+        source = root / name
+        bundled = app / 'Contents/Resources/Switch2KitNotices' / name
+        if not bundled.is_file() or bundled.is_symlink() or bundled.read_bytes() != source.read_bytes():
+            raise ValueError('Missing or altered bundled notice: ' + name)
+        digests[name] = hashlib.sha256(source.read_bytes()).hexdigest()
+    return {'version': 1, 'emulator': emulator, 'copyright_notice': notice,
+            'notices': digests}
+
+
+def main():
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument('emulator', choices=('dolphin', 'cemu'))
+    parser.add_argument('source', type=Path)
+    parser.add_argument('build', type=Path)
+    options = parser.parse_args()
+    report = options.build / 'integration-notices.json'
+    report.unlink(missing_ok=True)
+    directory = options.build / 'Binaries' if options.emulator == 'dolphin' else options.source / 'bin'
+    apps = [app for app in directory.glob('*.app')
+            if (app / 'Contents/Frameworks/libSwitch2KitC.dylib').is_file()]
+    if len(apps) != 1:
+        raise ValueError('Expected exactly one integrated application')
+    result = verify(apps[0], options.emulator)
+    report.write_text(json.dumps(result, indent=2) + '\n')
+    print('PASS bundled notices and upstream Finder metadata')
+
+
+if __name__ == '__main__':
+    main()

tests/distribution-notices/run.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+set -euo pipefail
+python3 "$(dirname "$0")/test_notices.py"

tests/distribution-notices/test_notices.py

@@ -0,0 +1,94 @@
+import importlib.util
+import hashlib
+from pathlib import Path
+import plistlib
+import tempfile
+import unittest
+
+ROOT = Path(__file__).resolve().parents[2]
+spec = importlib.util.spec_from_file_location('notices', ROOT / 'scripts/verify-distribution-notices.py')
+notices = importlib.util.module_from_spec(spec)
+spec.loader.exec_module(notices)
+
+
+class NoticesTests(unittest.TestCase):
+    def fixture(self, base, emulator):
+        app = base / 'Host with spaces.app'
+        for name in notices.NOTICES:
+            target = app / 'Contents/Resources/Switch2KitNotices' / name
+            target.parent.mkdir(parents=True, exist_ok=True)
+            target.write_bytes((ROOT / name).read_bytes())
+        info = {'CFBundleIdentifier': 'org.dolphin-emu.dolphin' if emulator == 'dolphin' else 'info.cemu.Cemu',
+                'NSHumanReadableCopyright': 'Licensed under GPL version 2 or later (GPLv2+)' if emulator == 'dolphin'
+                else 'Copyright © 2026 Cemu Project'}
+        (app / 'Contents/Info.plist').write_bytes(plistlib.dumps(info))
+        return app, info
+
+    def test_both_upstream_notices_and_all_source_texts_are_retained(self):
+        for emulator in ('dolphin', 'cemu'):
+            with tempfile.TemporaryDirectory() as temporary:
+                app, info = self.fixture(Path(temporary), emulator)
+                result = notices.verify(app, emulator)
+                self.assertEqual(result['copyright_notice'], info['NSHumanReadableCopyright'])
+                self.assertEqual(set(result['notices']), set(notices.NOTICES))
+                self.assertEqual(result['emulator'], emulator)
+                for name, digest in result['notices'].items():
+                    self.assertEqual(digest, hashlib.sha256((ROOT / name).read_bytes()).hexdigest())
+
+    def test_missing_empty_or_reassigned_copyright_fails(self):
+        for emulator in ('dolphin', 'cemu'):
+            for value in (None, '', '   ', 42, '© Switch2Kit'):
+                with self.subTest(emulator=emulator, value=value), tempfile.TemporaryDirectory() as temporary:
+                    app, info = self.fixture(Path(temporary), emulator)
+                    if value is None:
+                        del info['NSHumanReadableCopyright']
+                    else:
+                        info['NSHumanReadableCopyright'] = value
+                    (app / 'Contents/Info.plist').write_bytes(plistlib.dumps(info))
+                    with self.assertRaises(ValueError):
+                        notices.verify(app, emulator)
+
+    def test_missing_altered_or_symlinked_notice_fails(self):
+        for name in notices.NOTICES:
+            for defect in ('missing', 'changed', 'symlink'):
+                with self.subTest(name=name, defect=defect), tempfile.TemporaryDirectory() as temporary:
+                    app, _ = self.fixture(Path(temporary), 'dolphin')
+                    target = app / 'Contents/Resources/Switch2KitNotices' / name
+                    target.unlink()
+                    if defect == 'changed':
+                        target.write_text('Not the retained notice')
+                    elif defect == 'symlink':
+                        target.symlink_to(ROOT / name)
+                    with self.assertRaises(ValueError):
+                        notices.verify(app, 'dolphin')
+
+    def test_emulator_identity_cannot_be_reassigned(self):
+        with tempfile.TemporaryDirectory() as temporary:
+            app, _ = self.fixture(Path(temporary), 'dolphin')
+            with self.assertRaises(ValueError):
+                notices.verify(app, 'cemu')
+
+    def test_packagers_copy_notices_before_signing_or_archiving(self):
+        app = (ROOT / 'scripts/build-app.sh').read_text()
+        self.assertLess(app.index('cp -R LICENSES'), app.index('codesign --force'))
+        native = (ROOT / 'scripts/build-switch2kit-c.sh').read_text()
+        self.assertLess(native.index('cp -R "$ROOT/LICENSES"'), native.index('ditto -c -k'))
+        bundle = (ROOT / 'Integrations/CMake/Bundle.cmake').read_text()
+        self.assertIn('LINK_DEPENDS "${_notice_root}/CREDITS.md"', bundle)
+        self.assertIn('copy_directory "${_notice_root}/LICENSES"', bundle)
+        self.assertNotIn('COMMAND codesign', bundle)
+        self.assertIn('verify-distribution-notices.py', (ROOT / 'scripts/build-switch2kit-emulator.sh').read_text())
+
+    def test_notice_index_links_sources_and_retained_texts(self):
+        text = (ROOT / 'LICENSES/README.md').read_text()
+        self.assertIn('https://github.com/Peterksharma/switch2mac/tree/', text)
+        self.assertIn('[CREDITS.md](../CREDITS.md)', text)
+        for name in ('MIT-trevlars.txt', 'SDL-zlib.txt'):
+            self.assertIn('(' + name + ')', text)
+        self.assertIn('modified, unofficial SDL sources', text)
+        self.assertIn('Permission is hereby granted', (ROOT / 'LICENSES/MIT-trevlars.txt').read_text())
+        self.assertIn('This notice may not be removed', (ROOT / 'LICENSES/SDL-zlib.txt').read_text())
+
+
+if __name__ == '__main__':
+    unittest.main()