Flutter iOS Embedder
FlutterDartProject.mm File Reference
#import "flutter/shell/platform/darwin/ios/framework/Source/FlutterDartProject_Internal.h"
#import <Metal/Metal.h>
#import <UIKit/UIKit.h>
#include <syslog.h>
#include "flutter/common/constants.h"
#include "flutter/shell/common/switches.h"
#import "flutter/shell/platform/darwin/common/command_line.h"

Go to the source code of this file.

Macros

#define FML_USED_ON_EMBEDDER
 

Functions

static BOOL DoesHardwareSupportWideGamut ()
 
flutter::Settings FLTDefaultSettingsForBundle (NSBundle *bundle, NSProcessInfo *processInfoOrNil)
 

Variables

const FLUTTER_ASSERT_ARC uint8_t kPlatformStrongDill []
 
const intptr_t kPlatformStrongDillSize
 
static const char * kApplicationKernelSnapshotFileName = "kernel_blob.bin"
 

Macro Definition Documentation

◆ FML_USED_ON_EMBEDDER

#define FML_USED_ON_EMBEDDER

Definition at line 5 of file FlutterDartProject.mm.

Function Documentation

◆ DoesHardwareSupportWideGamut()

static BOOL DoesHardwareSupportWideGamut ( )
static

Definition at line 30 of file FlutterDartProject.mm.

30  {
31  static BOOL result = NO;
32  static dispatch_once_t once_token = 0;
33  dispatch_once(&once_token, ^{
34  id<MTLDevice> device = MTLCreateSystemDefaultDevice();
35  if (@available(iOS 13.0, *)) {
36  // MTLGPUFamilyApple2 = A9/A10
37  result = [device supportsFamily:MTLGPUFamilyApple2];
38  } else {
39  // A9/A10 on iOS 10+
40  result = [device supportsFeatureSet:MTLFeatureSet_iOS_GPUFamily3_v2];
41  }
42  });
43  return result;
44 }

Referenced by FLTDefaultSettingsForBundle().

◆ FLTDefaultSettingsForBundle()

flutter::Settings FLTDefaultSettingsForBundle ( NSBundle *  bundle,
NSProcessInfo *  processInfoOrNil 
)

Definition at line 46 of file FlutterDartProject.mm.

46  {
47  auto command_line = flutter::CommandLineFromNSProcessInfo(processInfoOrNil);
48 
49  // Precedence:
50  // 1. Settings from the specified NSBundle (except for enable-impeller).
51  // 2. Settings passed explicitly via command-line arguments.
52  // 3. Settings from the NSBundle with the default bundle ID.
53  // 4. Settings from the main NSBundle and default values.
54 
55  NSBundle* mainBundle = FLTGetApplicationBundle();
56  NSBundle* engineBundle = [NSBundle bundleForClass:[FlutterDartProject class]];
57 
58  bool hasExplicitBundle = bundle != nil;
59  if (bundle == nil) {
60  bundle = FLTFrameworkBundleWithIdentifier([FlutterDartProject defaultBundleIdentifier]);
61  }
62 
63  auto settings = flutter::SettingsFromCommandLine(command_line);
64 
65  settings.task_observer_add = [](intptr_t key, const fml::closure& callback) {
66  fml::MessageLoop::GetCurrent().AddTaskObserver(key, callback);
67  };
68 
69  settings.task_observer_remove = [](intptr_t key) {
70  fml::MessageLoop::GetCurrent().RemoveTaskObserver(key);
71  };
72 
73  settings.log_message_callback = [](const std::string& tag, const std::string& message) {
74  // TODO(cbracken): replace this with os_log-based approach.
75  // https://github.com/flutter/flutter/issues/44030
76  std::stringstream stream;
77  if (!tag.empty()) {
78  stream << tag << ": ";
79  }
80  stream << message;
81  std::string log = stream.str();
82  syslog(LOG_ALERT, "%.*s", (int)log.size(), log.c_str());
83  };
84 
85  settings.enable_platform_isolates = true;
86 
87  // The command line arguments may not always be complete. If they aren't, attempt to fill in
88  // defaults.
89 
90  // Flutter ships the ICU data file in the bundle of the engine. Look for it there.
91  if (settings.icu_data_path.empty()) {
92  NSString* icuDataPath = [engineBundle pathForResource:@"icudtl" ofType:@"dat"];
93  if (icuDataPath.length > 0) {
94  settings.icu_data_path = icuDataPath.UTF8String;
95  }
96  }
97 
98  if (flutter::DartVM::IsRunningPrecompiledCode()) {
99  if (hasExplicitBundle) {
100  NSString* executablePath = bundle.executablePath;
101  if ([[NSFileManager defaultManager] fileExistsAtPath:executablePath]) {
102  settings.application_library_path.push_back(executablePath.UTF8String);
103  }
104  }
105 
106  // No application bundle specified. Try a known location from the main bundle's Info.plist.
107  if (settings.application_library_path.empty()) {
108  NSString* libraryName = [mainBundle objectForInfoDictionaryKey:@"FLTLibraryPath"];
109  NSString* libraryPath = [mainBundle pathForResource:libraryName ofType:@""];
110  if (libraryPath.length > 0) {
111  NSString* executablePath = [NSBundle bundleWithPath:libraryPath].executablePath;
112  if (executablePath.length > 0) {
113  settings.application_library_path.push_back(executablePath.UTF8String);
114  }
115  }
116  }
117 
118  // In case the application bundle is still not specified, look for the App.framework in the
119  // Frameworks directory.
120  if (settings.application_library_path.empty()) {
121  NSString* applicationFrameworkPath = [mainBundle pathForResource:@"Frameworks/App.framework"
122  ofType:@""];
123  if (applicationFrameworkPath.length > 0) {
124  NSString* executablePath =
125  [NSBundle bundleWithPath:applicationFrameworkPath].executablePath;
126  if (executablePath.length > 0) {
127  settings.application_library_path.push_back(executablePath.UTF8String);
128  }
129  }
130  }
131  }
132 
133  // Checks to see if the flutter assets directory is already present.
134  if (settings.assets_path.empty()) {
135  NSString* assetsPath = FLTAssetsPathFromBundle(bundle);
136 
137  if (assetsPath.length == 0) {
138  NSLog(@"Failed to find assets path for \"%@\"", bundle);
139  } else {
140  settings.assets_path = assetsPath.UTF8String;
141 
142  // Check if there is an application kernel snapshot in the assets directory we could
143  // potentially use. Looking for the snapshot makes sense only if we have a VM that can use
144  // it.
145  if (!flutter::DartVM::IsRunningPrecompiledCode()) {
146  NSURL* applicationKernelSnapshotURL =
147  [NSURL URLWithString:@(kApplicationKernelSnapshotFileName)
148  relativeToURL:[NSURL fileURLWithPath:assetsPath]];
149  NSError* error;
150  if ([applicationKernelSnapshotURL checkResourceIsReachableAndReturnError:&error]) {
151  settings.application_kernel_asset = applicationKernelSnapshotURL.path.UTF8String;
152  } else {
153  NSLog(@"Failed to find snapshot at %@: %@", applicationKernelSnapshotURL.path, error);
154  }
155  }
156  }
157  }
158 
159  // Domain network configuration
160  // Disabled in https://github.com/flutter/flutter/issues/72723.
161  // Re-enable in https://github.com/flutter/flutter/issues/54448.
162  settings.may_insecurely_connect_to_all_domains = true;
163  settings.domain_network_policy = "";
164 
165  // Whether to enable wide gamut colors.
166 #if TARGET_OS_SIMULATOR
167  // As of Xcode 14.1, the wide gamut surface pixel formats are not supported by
168  // the simulator.
169  settings.enable_wide_gamut = false;
170  // Removes unused function warning.
172 #else
173  NSNumber* nsEnableWideGamut = [mainBundle objectForInfoDictionaryKey:@"FLTEnableWideGamut"];
174  BOOL enableWideGamut =
175  (nsEnableWideGamut ? nsEnableWideGamut.boolValue : YES) && DoesHardwareSupportWideGamut();
176  settings.enable_wide_gamut = enableWideGamut;
177 #endif
178 
179  // TODO(dnfield): We should reverse the order for all these settings so that command line options
180  // are preferred to plist settings. https://github.com/flutter/flutter/issues/124049
181  // Whether to enable Impeller. If the command line explicitly
182  // specified an option for this, ignore what's in the plist.
183  if (!command_line.HasOption("enable-impeller")) {
184  // Next, look in the app bundle.
185  NSNumber* enableImpeller = [bundle objectForInfoDictionaryKey:@"FLTEnableImpeller"];
186  if (enableImpeller == nil) {
187  // If it isn't in the app bundle, look in the main bundle.
188  enableImpeller = [mainBundle objectForInfoDictionaryKey:@"FLTEnableImpeller"];
189  }
190  // Change the default only if the option is present.
191  if (enableImpeller != nil) {
192  settings.enable_impeller = enableImpeller.boolValue;
193  }
194  }
195 
196  settings.warn_on_impeller_opt_out = true;
197 
198  NSNumber* enableTraceSystrace = [mainBundle objectForInfoDictionaryKey:@"FLTTraceSystrace"];
199  // Change the default only if the option is present.
200  if (enableTraceSystrace != nil) {
201  settings.trace_systrace = enableTraceSystrace.boolValue;
202  }
203 
204  NSNumber* enableDartAsserts = [mainBundle objectForInfoDictionaryKey:@"FLTEnableDartAsserts"];
205  if (enableDartAsserts != nil) {
206  settings.dart_flags.push_back("--enable-asserts");
207  }
208 
209  NSNumber* enableDartProfiling = [mainBundle objectForInfoDictionaryKey:@"FLTEnableDartProfiling"];
210  // Change the default only if the option is present.
211  if (enableDartProfiling != nil) {
212  settings.enable_dart_profiling = enableDartProfiling.boolValue;
213  }
214 
215  // Leak Dart VM settings, set whether leave or clean up the VM after the last shell shuts down.
216  NSNumber* leakDartVM = [mainBundle objectForInfoDictionaryKey:@"FLTLeakDartVM"];
217  // It will change the default leak_vm value in settings only if the key exists.
218  if (leakDartVM != nil) {
219  settings.leak_vm = leakDartVM.boolValue;
220  }
221 
222 #if FLUTTER_RUNTIME_MODE == FLUTTER_RUNTIME_MODE_DEBUG
223  // There are no ownership concerns here as all mappings are owned by the
224  // embedder and not the engine.
225  auto make_mapping_callback = [](const uint8_t* mapping, size_t size) {
226  return [mapping, size]() { return std::make_unique<fml::NonOwnedMapping>(mapping, size); };
227  };
228 
229  settings.dart_library_sources_kernel =
230  make_mapping_callback(kPlatformStrongDill, kPlatformStrongDillSize);
231 #endif // FLUTTER_RUNTIME_MODE == FLUTTER_RUNTIME_MODE_DEBUG
232 
233  // If we even support setting this e.g. from the command line or the plist,
234  // we should let the user override it.
235  // Otherwise, we want to set this to a value that will avoid having the OS
236  // kill us. On most iOS devices, that happens somewhere near half
237  // the available memory.
238  // The VM expects this value to be in megabytes.
239  if (settings.old_gen_heap_size <= 0) {
240  settings.old_gen_heap_size = std::round([NSProcessInfo processInfo].physicalMemory * .48 /
241  flutter::kMegaByteSizeInBytes);
242  }
243 
244  // This is the formula Android uses.
245  // https://android.googlesource.com/platform/frameworks/base/+/39ae5bac216757bc201490f4c7b8c0f63006c6cd/libs/hwui/renderthread/CacheManager.cpp#45
246  CGFloat scale = [UIScreen mainScreen].scale;
247  CGFloat screenWidth = [UIScreen mainScreen].bounds.size.width * scale;
248  CGFloat screenHeight = [UIScreen mainScreen].bounds.size.height * scale;
249  settings.resource_cache_max_bytes_threshold = screenWidth * screenHeight * 12 * 4;
250 
251  // Whether to enable ios embedder api.
252  NSNumber* enable_embedder_api =
253  [mainBundle objectForInfoDictionaryKey:@"FLTEnableIOSEmbedderAPI"];
254  // Change the default only if the option is present.
255  if (enable_embedder_api) {
256  settings.enable_embedder_api = enable_embedder_api.boolValue;
257  }
258 
259  return settings;
260 }

References flutter::CommandLineFromNSProcessInfo(), DoesHardwareSupportWideGamut(), FLTAssetsPathFromBundle(), FLTFrameworkBundleWithIdentifier(), FLTGetApplicationBundle(), kApplicationKernelSnapshotFileName, kPlatformStrongDill, and kPlatformStrongDillSize.

Referenced by FlutterDartProject::initWithPrecompiledDartBundle:.

Variable Documentation

◆ kApplicationKernelSnapshotFileName

const char* kApplicationKernelSnapshotFileName = "kernel_blob.bin"
static

Definition at line 28 of file FlutterDartProject.mm.

Referenced by FLTDefaultSettingsForBundle().

◆ kPlatformStrongDill

const FLUTTER_ASSERT_ARC uint8_t kPlatformStrongDill[]

◆ kPlatformStrongDillSize

const intptr_t kPlatformStrongDillSize
kApplicationKernelSnapshotFileName
static const char * kApplicationKernelSnapshotFileName
Definition: FlutterDartProject.mm:28
kPlatformStrongDillSize
const intptr_t kPlatformStrongDillSize
kPlatformStrongDill
const FLUTTER_ASSERT_ARC uint8_t kPlatformStrongDill[]
DoesHardwareSupportWideGamut
static BOOL DoesHardwareSupportWideGamut()
Definition: FlutterDartProject.mm:30
FLTGetApplicationBundle
NSBundle * FLTGetApplicationBundle()
Definition: FlutterNSBundleUtils.mm:32
flutter::CommandLineFromNSProcessInfo
fml::CommandLine CommandLineFromNSProcessInfo(NSProcessInfo *processInfoOrNil=nil)
Definition: command_line.mm:11
FLTFrameworkBundleWithIdentifier
NSBundle * FLTFrameworkBundleWithIdentifier(NSString *flutterFrameworkBundleID)
Definition: FlutterNSBundleUtils.mm:43
FLTAssetsPathFromBundle
NSString * FLTAssetsPathFromBundle(NSBundle *bundle)
Definition: FlutterNSBundleUtils.mm:61
FlutterDartProject
Definition: FlutterDartProject.mm:262