### Implement C Source

Source: https://pub.dev/packages/ffigen

The source file provides the implementation for the functions declared in the header.

```c
// in src/add.c:
   
int add(int a, int b) {
  return a + b;
}
```

--------------------------------

### Enable FFigen Native Support

Source: https://pub.dev/packages/ffigen

Use the `ffi-native` option to generate `@Native` bindings. This is an experimental feature and the API may change.

```yaml
ffi-native:
  asset-id: 'package:some_pkg/asset' # Optional, was assetId in previous versions
```

--------------------------------

### Set file preamble

Source: https://pub.dev/packages/ffigen

Defines a raw header to be prepended to the generated file.

```yaml
preamble: |
  // ignore_for_file: camel_case_types, non_constant_identifier_names
```

--------------------------------

### Define Header Entry Points and Include Directives

Source: https://pub.dev/packages/ffigen

Specifies the header files that FFIgen should process. 'entry-points' are the primary headers, and 'include-directives' are additional headers to be included. Glob syntax is supported.

```yaml
headers:
  entry-points:
    - 'folder/**.h'
    - 'folder/specific_header.h'
  include-directives:
    - '**index.h'
    - '**/clang-c/**'
    - '/full/path/to/a/header.h'
```

--------------------------------

### Output Configuration

Source: https://pub.dev/packages/ffigen

Configure the output paths for generated bindings, including Objective-C bindings and symbol files.

```APIDOC
## Output Configuration

Configure where generated code and symbol files are placed.

### Objective-C Bindings:

Choose where the generated ObjC code (if any) is placed. The default path is `'${output.bindings}.m'`.

```yaml
output:
  objc-bindings: 'generated_bindings.m'
```

This ObjC file will only be generated if it's needed. If it is generated, it must be compiled into your package.

### Symbol File:

Generates a symbol file yaml containing all types defined in the generated output.

```yaml
output:
  symbol-file:
    output: 'package:some_pkg/symbols.yaml'
    import-path: 'package:some_pkg/base.dart'
```

**Note:** Although file paths are supported for `output`, prefer Package URIs for `output` and `import-path` so that other packages can use them.
```

--------------------------------

### FFI Native Bindings

Source: https://pub.dev/packages/ffigen

Configure the generation of native bindings using `@Native`. This is an experimental feature and the API may change.

```APIDOC
## FFI Native Bindings

Generate `@Native` bindings instead of using `DynamicLibrary` or `lookup`.

### Configuration:

```yaml
ffi-native:
  asset-id: 'package:some_pkg/asset' # Optional, was assetId in previous versions
```

**Note:** Native support is EXPERIMENTAL. The API may change in a breaking way without notice.
```

--------------------------------

### Configure LLVM Path for Clang

Source: https://pub.dev/packages/ffigen

Specifies the paths to the LLVM folder, which is necessary for FFIgen to locate the Clang library. FFIgen searches sequentially in the provided paths. This is required if Clang cannot be found in default locations.

```yaml
llvm-path:
  - '/usr/local/opt/llvm'
  - 'C:\\Program Files\\llvm`
  - '/usr/lib/llvm-11'
  # Specify exact path to dylib
  - '/usr/lib64/libclang.so'
```

--------------------------------

### Generate Symbol File in FFigen

Source: https://pub.dev/packages/ffigen

Configure FFigen to generate a symbol file containing all defined types. Prefer Package URIs for the output path to allow other packages to use it. An `import-path` can also be specified.

```yaml
output:
  ... 
  symbol-file:
    # Although file paths are supported here, prefer Package Uri's here
    # so that other pacakges can use them.
    output: 'package:some_pkg/symbols.yaml'
    import-path: 'package:some_pkg/base.dart'
```

--------------------------------

### Configure Objective-C Bindings Output

Source: https://pub.dev/packages/ffigen

Specify the output path for generated Objective-C code. The default path is `${output.bindings}.m`. This file is only generated if needed and must be compiled into your package.

```yaml
output:
  ... 
  objc-bindings: 'generated_bindings.m'
```

--------------------------------

### Specify Input Language for FFigen

Source: https://pub.dev/packages/ffigen

Choose the input language for FFigen. Supported options are 'c' (default) and 'objc'. This is an experimental feature and the API may change.

```yaml
language: 'objc'
```

--------------------------------

### Add module prefixes for Swift-wrapped Objective-C libraries

Source: https://pub.dev/packages/ffigen

Use module prefixes when loading interfaces or protocols from dylibs that are generated wrappers for Swift libraries.

```yaml
headers:
  entry-points:
    # Generated by swiftc to wrap foo_lib.swift.
    - 'foo_lib-Swift.h'
objc-interfaces:
  include:
    # Eg, foo_lib contains a set of classes prefixed with FL.
    - 'FL.*'
  module:
    # Use 'foo_lib' as the module name for all the FL.* classes.
    # We don't match .* here because other classes like NSString
    # shouldn't be given a module prefix.
    'FL.*': 'foo_lib'
```

--------------------------------

### Configure Automatic C Standard Library Inclusion on macOS

Source: https://pub.dev/packages/ffigen

Controls whether FFIgen should attempt to automatically find and include the C standard library path in compiler options on macOS. Defaults to true.

```yaml
compiler-opts-automatic:
  macos:
    include-c-standard-library: false
```

--------------------------------

### Provide Dart Doc Description for Generated Class

Source: https://pub.dev/packages/ffigen

Adds a Dart documentation comment to the generated binding class, explaining its purpose. This is a preferred option for documentation.

```yaml
description: 'Bindings to SQLite'
```

--------------------------------

### Configure variadic arguments

Source: https://pub.dev/packages/ffigen

Defines function signatures for variadic arguments, supporting native C types, common typedefs, and custom structs.

```yaml
functions:
  variadic-arguments:
    myfunc:
      // Native C types are supported
      - [int, unsigned char, long*, float**]
      // Common C typedefs (stddef.h) are supported too
      - [uint8_t, intptr_t, size_t, wchar_t*]
      // Structs/Unions/Typedefs from generated code or a library import can be referred too.
      - [MyStruct*, my_custom_lib.CustomUnion]
```

--------------------------------

### Specify Output Path for Generated Bindings

Source: https://pub.dev/packages/ffigen

Defines the location where the generated Dart bindings file will be saved. This is a required configuration option.

```yaml
output: 'generated_bindings.dart'
```

```yaml
output:
  bindings: 'generated_bindings.dart'
  ...
```

--------------------------------

### Import Symbol Files

Source: https://pub.dev/packages/ffigen

Import symbols from a symbol file, which is useful for sharing type definitions between packages.

```APIDOC
## Import Symbol Files

Import symbols from a symbol file. Used for sharing type definitions from other packages.

### Configuration:

```yaml
import:
  symbol-files:
    - 'package:some_pkg/symbols.yaml'
    - 'path/to/some/symbol_file.yaml'
```

Both package URIs and file paths are supported here.
```

--------------------------------

### Call Generated FFI Bindings

Source: https://pub.dev/packages/ffigen

Import the generated Dart file to invoke the native C functions.

```dart
import 'add.g.dart';

// ...
   
void answerToLife() {
  print('The answer to the Ultimate Question is ${add(40, 2)}!');
}
```

--------------------------------

### Enable full code generation for transitive dependencies

Source: https://pub.dev/packages/ffigen

Set these flags to true to fully generate bindings for interfaces and protocols that are transitively depended upon, rather than generating stubs or omitting them.

```yaml
include-transitive-objc-interfaces: true
include-transitive-objc-protocols: true
```

--------------------------------

### Configure FfiGenerator

Source: https://pub.dev/packages/ffigen

A Dart script used to configure and run the FfiGenerator to produce bindings.

```dart
import 'dart:io';

import 'package:ffigen/ffigen.dart';
   
void main() {
  final packageRoot = Platform.script.resolve('../');
  FfiGenerator(
    // Required. Output path for the generated bindings.
    output: Output(dartFile: packageRoot.resolve('lib/add.g.dart')),
    // Optional. Where to look for header files.
    headers: Headers(entryPoints: [packageRoot.resolve('src/add.h')]),
    // Optional. What functions to generate bindings for.
    functions: Functions.includeSet({'add'}),
  ).generate();
}
```

--------------------------------

### Configure Objective-C interface, protocol, and category filters

Source: https://pub.dev/packages/ffigen

Use these filters to include, exclude, or rename specific Objective-C declarations in the generated bindings.

```yaml
objc-interfaces:
  include:
    # Includes a specific interface.
    - 'MyInterface'
    # Includes all interfaces starting with "NS".
    - 'NS.*'
  exclude:
    # Override the above NS.* inclusion, to exclude NSURL.
    - 'NSURL'
  rename:
    # Removes '_' prefix from interface names.
    '_(.*)': '$1'
objc-protocols:
  include:
    # Generates bindings for a specific protocol.
    - MyProtocol
objc-categories:
  include:
    # Generates bindings for a specific category.
    - MyCategory
```

--------------------------------

### Import Symbols from Symbol Files

Source: https://pub.dev/packages/ffigen

Import type definitions from symbol files of other packages. Both package URIs and file paths are supported for specifying the symbol files.

```yaml
import:
  symbol-files:
    # Both package Uri and file paths are supported here.
    - 'package:some_pkg/symbols.yaml'
    - 'path/to/some/symbol_file.yaml'
```

--------------------------------

### Pass Compiler Options to Clang

Source: https://pub.dev/packages/ffigen

Allows specifying compiler flags to be passed to Clang during the binding generation process. These options can also be provided via the command line.

```yaml
compiler-opts:
  - '-I/usr/lib/llvm-9/include/'
```

```bash
dart run ffigen --compiler-opts "-I/headers
-L 'path/to/folder name/file'"
```

--------------------------------

### Sort bindings

Source: https://pub.dev/packages/ffigen

Enables sorting of generated bindings by name.

```yaml
sort: true
```

--------------------------------

### Use Dart handle

Source: https://pub.dev/packages/ffigen

Enables mapping of Dart_Handle to the Handle type.

```yaml
use-dart-handle: true
```

--------------------------------

### Use supported typedefs

Source: https://pub.dev/packages/ffigen

Enables automatic mapping of standard C typedefs to Dart FFI types.

```yaml
use-supported-typedefs: true
```

--------------------------------

### Language Selection

Source: https://pub.dev/packages/ffigen

Specify the input language for code generation. Supported languages are 'c' and 'objc'.

```APIDOC
## Language Selection

Choose the input language. Must be one of 'c', or 'objc'. Defaults to 'c'.

### Configuration:

```yaml
language: 'objc'
```

**Note:** Other language support is EXPERIMENTAL. The API may change in a breaking way without notice.
```

--------------------------------

### Expose function typedefs

Source: https://pub.dev/packages/ffigen

Configures which functions should have their Native and Dart type typedefs generated.

```yaml
functions:
  expose-typedefs:
    include:
      # Match function name.
      - 'myFunc'
       # Do this to expose types for all function.
      - '.*'
    exclude:
      # If you only use exclude, then everything
      # not excluded is generated.
      - 'dispose'
```

--------------------------------

### Ignore source errors

Source: https://pub.dev/packages/ffigen

Configures whether to ignore compiler warnings or errors found in source header files.

```yaml
ignore-source-errors: true
```

```bash
dart run ffigen --ignore-source-errors
```

--------------------------------

### External Versions

Source: https://pub.dev/packages/ffigen

Filter generated bindings based on platform version. APIs deprecated before the minimum specified version for a platform will be omitted.

```APIDOC
## External Versions

Filter generated bindings based on platform version. APIs deprecated before the minimum specified version for a platform will be omitted.

### Configuration:

```yaml
external-versions:
  ios:
    min: 12.0.0
  macos:
    min: 10.14.0
```

Current supported OS keys are `ios` and `macos`. If you have a use case for version checking on other OSs, please file an issue.

The API's inclusion will be based on the platforms that have a specified minimum version.
```

--------------------------------

### Define Build Hook

Source: https://pub.dev/packages/ffigen

A build hook script to compile C sources into native assets for the Dart application.

```dart
import 'package:code_assets/code_assets.dart';
import 'package:hooks/hooks.dart';
import 'package:native_toolchain_c/native_toolchain_c.dart';
   
void main(List<String> args) async {
  await build(args, (input, output) async {
    if (input.config.buildCodeAssets) {
      final builder = CBuilder.library(
        name: 'add',
        assetName: 'add.g.dart',
        sources: ['src/add.c'],
      );
      await builder.run(input: input, output: output);
    }
  });
}
```

--------------------------------

### Define C Header

Source: https://pub.dev/packages/ffigen

The header file defines the C API interface to be exposed to Dart.

```c
// in src/add.h:
   
int add(int a, int b);
```

--------------------------------

### Configure External Versioning for Deprecated APIs

Source: https://pub.dev/packages/ffigen

Omit APIs deprecated as of the minimum specified platform version from generated bindings. APIs are generated if available on any targeted platform version. Currently supports 'ios' and 'macos'.

```yaml
external-versions:
  # See https://docs.flutter.dev/reference/supported-platforms.
  ios:
    min: 12.0.0
  macos:
    min: 10.14.0
```

--------------------------------

### Define library imports

Source: https://pub.dev/packages/ffigen

Specifies external library imports for use within type mappings.

```yaml
library-imports:
  custom_lib: 'package:some_pkg/some_file.dart'
```

--------------------------------

### Set leaf functions

Source: https://pub.dev/packages/ffigen

Configures functions to be marked as leaf, which can improve performance for short-running native calls.

```yaml
functions:
  leaf:
    include:
      # Match function name.
      - 'myFunc'
       # Do this to set isLeaf:true for all functions.
      - '.*'
    exclude:
      # If you only use exclude, then everything
      # not excluded is generated.
      - 'dispose'
```

--------------------------------

### Configure dependency-only generation

Source: https://pub.dev/packages/ffigen

Sets generation behavior for structs and unions that are only dependencies and not explicitly included.

```yaml
structs:
  dependency-only: opaque
unions:
  dependency-only: opaque
```

--------------------------------

### Filter members of Objective-C interfaces, protocols, and categories

Source: https://pub.dev/packages/ffigen

Define specific inclusion or exclusion rules for methods and properties within interfaces, protocols, or categories using regex patterns.

```yaml
objc-interfaces:
  member-filter:
    MyInterface:
      include:
        - "someMethod:withArg:"
      # Since MyInterface has an include rule, all other methods
      # are excluded by default.
objc-protocols:
  member-filter:
    NS.*:  # Matches all protocols starting with NS.
      exclude:
        - copy.*  # Remove all copy methods from these protocols.
objc-categories:
  member-filter:
    MyCategory:
      include:
        - init.*  # Include all init methods.
```

--------------------------------

### Exclude all by default

Source: https://pub.dev/packages/ffigen

Changes the default behavior to exclude all declarations unless explicitly included.

```yaml
exclude-all-by-default: true
```

--------------------------------

### Filter and Rename C Declarations (Functions, Structs, Enums, Globals)

Source: https://pub.dev/packages/ffigen

Provides options to include, exclude, and rename C functions, structs, unions, enums, and globals. It also allows renaming members of structs and enums, and exposing symbol addresses for functions and globals.

```yaml
functions:
  include: # 'exclude' is also available.
    # Matches using regexp.
    - '[a-z][a-zA-Z0-9]*'
    # '.' matches any character.
    - 'prefix.*'
    # Matches with exact name
    - 'someFuncName'
    # Full names have higher priority.
    - 'anotherName'
  rename:
    # Regexp groups based replacement.
    'clang_(.*)': '$1'
    'clang_dispose': 'dispose'
    # Removes '_' from beginning.
    '_(.*)': '$1'
  symbol-address:
    # Used to expose symbol address.
    include:
      - 'myFunc'
structs:
  rename:
    # Removes prefix underscores
    # from all structures.
    '_(.*)': '$1'
  member-rename:
    '.*': # Matches any struct.
      # Removes prefix underscores
      # from members.
      '_(.*)': '$1'
enums:
  rename:
    # Regexp groups based replacement.
    'CXType_(.*)': '$1'
  member-rename:
    '(.*)': # Matches any enum.
      # Removes '_' from beginning
      # enum member name.
      '_(.*)': '$1'
    # Full names have higher priority.
    'CXTypeKind':
      # $1 keeps only the 1st
      # group i.e only '(.*)'.
      'CXType(.*)': '$1'
  as-int:
    # These enums will be generated as Dart integers instead of Dart enums
    include:
      - 'MyIntegerEnum'
globals:
  exclude:
    - 'aGlobal'
  rename:
    # Removes '_' from
    # beginning of a name.
    '_(.*)': '$1'
```

--------------------------------

### Configure comment extraction

Source: https://pub.dev/packages/ffigen

Specifies the style and length of documentation comments to extract from source declarations.

```yaml
comments:
  style: any
  length: full
```

--------------------------------

### Map types

Source: https://pub.dev/packages/ffigen

Maps specific native types, typedefs, structs, or unions to custom types.

```yaml
type-map:
  'native-types': # Targets native types.
    'char':
      'lib': 'pkg_ffi' # predefined import.
      'c-type': 'Char'
```

--------------------------------

### Configure Native Types in FFigen

Source: https://pub.dev/packages/ffigen

Specify native types for Dart bindings. Use 'int', 'double', or 'float' for standard types, or define custom 'dart-type' mappings for specific C types.

```yaml
'dart-type': 'int'
    'int':
      'lib': 'custom_lib'
      'c-type': 'CustomType4'
      'dart-type': 'int'
  'typedefs': # Targets typedefs.
    'my_type1':
      'lib': 'custom_lib'
      'c-type': 'CustomType'
      'dart-type': 'CustomType'
  'structs': # Targets structs.
    'my_type2':
      'lib': 'custom_lib'
      'c-type': 'CustomType2'
      'dart-type': 'CustomType2'
  'unions': # Targets unions.
    'my_type3':
      'lib': 'custom_lib'
      'c-type': 'CustomType3'
      'dart-type': 'CustomType3'
```

--------------------------------

### Native Type Mappings

Source: https://pub.dev/packages/ffigen

Configure mappings between Dart types and C/Objective-C types for native bindings. This section shows how to define custom types for integers, typedefs, structs, and unions.

```APIDOC
## Native Type Mappings

FFigen allows for custom type mappings to handle specific C types.

### Example Mappings:

- **Integer Type**: Map a Dart integer type to a specific C type.
  ```yaml
  native-types:
    dart-type: 'int'
  int:
    lib: 'custom_lib'
    c-type: 'CustomType4'
    dart-type: 'int'
  ```

- **Typedefs**: Define custom Dart types for C typedefs.
  ```yaml
  typedefs:
    my_type1:
      lib: 'custom_lib'
      c-type: 'CustomType'
      dart-type: 'CustomType'
  ```

- **Structs**: Define custom Dart types for C structs.
  ```yaml
  structs:
    my_type2:
      lib: 'custom_lib'
      c-type: 'CustomType2'
      dart-type: 'CustomType2'
  ```

- **Unions**: Define custom Dart types for C unions.
  ```yaml
  unions:
    my_type3:
      lib: 'custom_lib'
      c-type: 'CustomType3'
      dart-type: 'CustomType3'
  ```
```

--------------------------------

### Set Name for Generated Binding Class

Source: https://pub.dev/packages/ffigen

Assigns a name to the generated Dart class that will encapsulate the FFI bindings. This is a preferred option for naming.

```yaml
name: 'SQLite'
```

--------------------------------

### Include Unused Typedefs

Source: https://pub.dev/packages/ffigen

A boolean flag to control whether typedefs that are not referred to anywhere in the C code should also be generated. Defaults to false.

```yaml
include-unused-typedefs: true
```

--------------------------------

### Silence enum warnings

Source: https://pub.dev/packages/ffigen

Silences warnings related to integer type mimicking for enums.

```yaml
silence-enum-warning: true
```

--------------------------------

### Filter and Rename Typedefs

Source: https://pub.dev/packages/ffigen

Allows filtering (including or excluding) and renaming of referred typedefs. By default, typedefs not referenced anywhere are not generated.

```yaml
typedefs:
  exclude:
    # Typedefs starting with `p` are not generated.
    - 'p.*'
  rename:
    # Removes '_' from beginning of a typedef.
    '_(.*)': '$1'
```

--------------------------------

### Disable automatic transitive category generation

Source: https://pub.dev/packages/ffigen

Set to false to prevent automatic inclusion of categories that extend included interfaces, allowing for manual filtering.

```yaml
include-transitive-objc-categories: false
```

--------------------------------

### Override struct packing

Source: https://pub.dev/packages/ffigen

Overrides the @Packed(X) annotation for generated structs using regex matching on generated names.

```yaml
structs:
  pack:
    # Matches with the generated name.
    'NoPackStruct': none # No packing
    '.*': 1 # Pack all structs with value 1
```

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