blob: 748275d26ead9357f06ad70c32a8fba001280013 [file] [log] [blame]
// Copyright (c) 2020, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
import 'package:ffigen/src/code_generator.dart';
import 'package:ffigen/src/code_generator/utils.dart';
import 'package:logging/logging.dart';
import '../strings.dart' as strings;
final _logger = Logger('ffigen.code_generator.writer');
/// To store generated String bindings.
class Writer {
final String? header;
/// Holds bindings, which lookup symbols.
final List<Binding> lookUpBindings;
/// Holds bindings, which lookup symbols through `FfiNative`.
final List<Binding> ffiNativeBindings;
/// Holds bindings which don't lookup symbols.
final List<Binding> noLookUpBindings;
/// Manages the `_SymbolAddress` class.
final symbolAddressWriter = SymbolAddressWriter();
late String _className;
String get className => _className;
final String? classDocComment;
String? _ffiLibraryPrefix;
String get ffiLibraryPrefix {
if (_ffiLibraryPrefix != null) {
return _ffiLibraryPrefix!;
}
final import = _usedImports.firstWhere(
(element) => element.name == ffiImport.name,
orElse: () => ffiImport);
_usedImports.add(import);
return _ffiLibraryPrefix = import.prefix;
}
String? _ffiPkgLibraryPrefix;
String get ffiPkgLibraryPrefix {
if (_ffiPkgLibraryPrefix != null) {
return _ffiPkgLibraryPrefix!;
}
final import = _usedImports.firstWhere(
(element) => element.name == ffiPkgImport.name,
orElse: () => ffiPkgImport);
_usedImports.add(import);
return _ffiPkgLibraryPrefix = import.prefix;
}
final Set<LibraryImport> _usedImports = {};
late String _lookupFuncIdentifier;
String get lookupFuncIdentifier => _lookupFuncIdentifier;
late String _symbolAddressClassName;
late String _symbolAddressVariableName;
late String _symbolAddressLibraryVarName;
/// Initial namers set after running constructor. Namers are reset to this
/// initial state everytime [generate] is called.
late UniqueNamer _initialTopLevelUniqueNamer, _initialWrapperLevelUniqueNamer;
/// Used by [Binding]s for generating required code.
late UniqueNamer _topLevelUniqueNamer, _wrapperLevelUniqueNamer;
UniqueNamer get topLevelUniqueNamer => _topLevelUniqueNamer;
UniqueNamer get wrapperLevelUniqueNamer => _wrapperLevelUniqueNamer;
late String _arrayHelperClassPrefix;
/// Guaranteed to be a unique prefix.
String get arrayHelperClassPrefix => _arrayHelperClassPrefix;
/// Set true after calling [generate]. Indicates if
/// [generateSymbolOutputYamlMap] can be called.
bool get canGenerateSymbolOutput => _canGenerateSymbolOutput;
bool _canGenerateSymbolOutput = false;
/// [_usedUpNames] should contain names of all the declarations which are
/// already used. This is used to avoid name collisions.
Writer({
required this.lookUpBindings,
required this.ffiNativeBindings,
required this.noLookUpBindings,
required String className,
Set<LibraryImport>? additionalImports,
this.classDocComment,
this.header,
}) {
final globalLevelNameSet = noLookUpBindings.map((e) => e.name).toSet();
final wrapperLevelNameSet = lookUpBindings.map((e) => e.name).toSet();
final allNameSet = <String>{}
..addAll(globalLevelNameSet)
..addAll(wrapperLevelNameSet);
_initialTopLevelUniqueNamer = UniqueNamer(globalLevelNameSet);
_initialWrapperLevelUniqueNamer = UniqueNamer(wrapperLevelNameSet);
final allLevelsUniqueNamer = UniqueNamer(allNameSet);
/// Wrapper class name must be unique among all names.
_className = _resolveNameConflict(
name: className,
makeUnique: allLevelsUniqueNamer,
markUsed: [_initialWrapperLevelUniqueNamer, _initialTopLevelUniqueNamer],
);
/// Library imports prefix should be unique unique among all names.
if (additionalImports != null) {
for (final lib in additionalImports) {
lib.prefix = _resolveNameConflict(
name: lib.prefix,
makeUnique: allLevelsUniqueNamer,
markUsed: [
_initialWrapperLevelUniqueNamer,
_initialTopLevelUniqueNamer
],
);
}
}
/// [_lookupFuncIdentifier] should be unique in top level.
_lookupFuncIdentifier = _resolveNameConflict(
name: '_lookup',
makeUnique: _initialTopLevelUniqueNamer,
markUsed: [_initialTopLevelUniqueNamer],
);
/// Resolve name conflicts of identifiers used for SymbolAddresses.
_symbolAddressClassName = _resolveNameConflict(
name: '_SymbolAddresses',
makeUnique: allLevelsUniqueNamer,
markUsed: [_initialWrapperLevelUniqueNamer, _initialTopLevelUniqueNamer],
);
_symbolAddressVariableName = _resolveNameConflict(
name: 'addresses',
makeUnique: _initialWrapperLevelUniqueNamer,
markUsed: [_initialWrapperLevelUniqueNamer],
);
_symbolAddressLibraryVarName = _resolveNameConflict(
name: '_library',
makeUnique: _initialWrapperLevelUniqueNamer,
markUsed: [_initialWrapperLevelUniqueNamer],
);
/// Finding a unique prefix for Array Helper Classes and store into
/// [_arrayHelperClassPrefix].
final base = 'ArrayHelper';
_arrayHelperClassPrefix = base;
var suffixInt = 0;
for (var i = 0; i < allNameSet.length; i++) {
if (allNameSet.elementAt(i).startsWith(_arrayHelperClassPrefix)) {
// Not a unique prefix, start over with a new suffix.
i = -1;
suffixInt++;
_arrayHelperClassPrefix = '$base$suffixInt';
}
}
_resetUniqueNamersNamers();
}
/// Resolved name conflict using [makeUnique] and marks the result as used in
/// all [markUsed].
String _resolveNameConflict({
required String name,
required UniqueNamer makeUnique,
List<UniqueNamer> markUsed = const [],
}) {
final s = makeUnique.makeUnique(name);
for (final un in markUsed) {
un.markUsed(s);
}
return s;
}
/// Resets the namers to initial state. Namers are reset before generating.
void _resetUniqueNamersNamers() {
_topLevelUniqueNamer = _initialTopLevelUniqueNamer.clone();
_wrapperLevelUniqueNamer = _initialWrapperLevelUniqueNamer.clone();
}
void markImportUsed(LibraryImport import) {
_usedImports.add(import);
}
/// Writes all bindings to a String.
String generate() {
final s = StringBuffer();
// We write the source first to determine which imports are actually
// referenced. Headers and [s] are then combined into the final result.
final result = StringBuffer();
// Reset unique namers to initial state.
_resetUniqueNamersNamers();
// Write file header (if any).
if (header != null) {
result.writeln(header);
}
// Write auto generated declaration.
result.write(makeDoc(
'AUTO GENERATED FILE, DO NOT EDIT.\n\nGenerated by `package:ffigen`.'));
/// Write [lookUpBindings].
if (lookUpBindings.isNotEmpty) {
// Write doc comment for wrapper class.
if (classDocComment != null) {
s.write(makeDartDoc(classDocComment!));
}
// Write wrapper classs.
s.write('class $_className{\n');
// Write dylib.
s.write('/// Holds the symbol lookup function.\n');
s.write(
'final $ffiLibraryPrefix.Pointer<T> Function<T extends $ffiLibraryPrefix.NativeType>(String symbolName) $lookupFuncIdentifier;\n');
s.write('\n');
//Write doc comment for wrapper class constructor.
s.write(makeDartDoc('The symbols are looked up in [dynamicLibrary].'));
// Write wrapper class constructor.
s.write(
'$_className($ffiLibraryPrefix.DynamicLibrary dynamicLibrary): $lookupFuncIdentifier = dynamicLibrary.lookup;\n\n');
//Write doc comment for wrapper class named constructor.
s.write(makeDartDoc('The symbols are looked up with [lookup].'));
// Write wrapper class named constructor.
s.write(
'$_className.fromLookup($ffiLibraryPrefix.Pointer<T> Function<T extends $ffiLibraryPrefix.NativeType>(String symbolName) lookup): $lookupFuncIdentifier = lookup;\n\n');
for (final b in lookUpBindings) {
s.write(b.toBindingString(this).string);
}
if (symbolAddressWriter.shouldGenerate) {
s.write(symbolAddressWriter.writeObject(this));
}
s.write('}\n\n');
}
for (final b in ffiNativeBindings) {
s.write(b.toBindingString(this).string);
}
if (symbolAddressWriter.shouldGenerate) {
s.write(symbolAddressWriter.writeClass(this));
}
/// Write [noLookUpBindings].
for (final b in noLookUpBindings) {
s.write(b.toBindingString(this).string);
}
// Write neccesary imports.
for (final lib in _usedImports) {
result
..write("import '${lib.importPath}' as ${lib.prefix};")
..write('\n');
}
result.write(s);
_canGenerateSymbolOutput = true;
return result.toString();
}
Map<String, dynamic> generateSymbolOutputYamlMap(String importFilePath) {
final bindings = <Binding>[
...noLookUpBindings,
...ffiNativeBindings,
...lookUpBindings
];
if (!canGenerateSymbolOutput) {
throw Exception(
"Invalid state: generateSymbolOutputYamlMap() called before generate()");
}
final result = <String, dynamic>{};
result[strings.formatVersion] = strings.symbolFileFormatVersion;
result[strings.files] = <String, dynamic>{};
result[strings.files][importFilePath] = <String, dynamic>{};
final fileConfig = result[strings.files][importFilePath];
fileConfig[strings.usedConfig] = <String, dynamic>{};
// Warn for macros.
final hasMacroBindings = bindings.any(
(element) => element is Constant && element.usr.contains('@macro@'));
if (hasMacroBindings) {
_logger.info(
'Removing all Macros from symbol file since they cannot be cross referenced reliably.');
}
// Remove internal bindings and macros.
bindings.removeWhere((element) {
return element.isInternal ||
(element is Constant && element.usr.contains('@macro@'));
});
// Sort bindings alphabetically by USR.
bindings.sort((a, b) => a.usr.compareTo(b.usr));
fileConfig[strings.usedConfig][strings.ffiNative] = bindings
.whereType<Func>()
.any((element) => element.ffiNativeConfig.enabled);
fileConfig[strings.symbols] = <String, dynamic>{};
final symbolConfig = fileConfig[strings.symbols];
for (final binding in bindings) {
symbolConfig[binding.usr] = {
strings.name: binding.name,
};
}
return result;
}
}
/// Manages the generated `_SymbolAddress` class.
class SymbolAddressWriter {
final List<_SymbolAddressUnit> _addresses = [];
/// Used to check if we need to generate `_SymbolAddress` class.
bool get shouldGenerate => _addresses.isNotEmpty;
void addSymbol({
required String type,
required String name,
required String ptrName,
}) {
_addresses.add(_SymbolAddressUnit(type, name, ptrName));
}
String writeObject(Writer w) {
return 'late final ${w._symbolAddressVariableName} = ${w._symbolAddressClassName}(this);';
}
String writeClass(Writer w) {
final sb = StringBuffer();
sb.write('class ${w._symbolAddressClassName} {\n');
// Write Library object.
sb.write('final ${w._className} ${w._symbolAddressLibraryVarName};\n');
// Write Constructor.
sb.write(
'${w._symbolAddressClassName}(this.${w._symbolAddressLibraryVarName});\n');
for (final address in _addresses) {
sb.write(
'${address.type} get ${address.name} => ${w._symbolAddressLibraryVarName}.${address.ptrName};\n');
}
sb.write('}\n');
return sb.toString();
}
}
/// Holds the data for a single symbol address.
class _SymbolAddressUnit {
final String type, name, ptrName;
_SymbolAddressUnit(this.type, this.name, this.ptrName);
}