---
title: mxiris-reverse-engineering/machoobjcsection
framework: Swift Package Catalog
role: article
path: packages/mxiris-reverse-engineering/machoobjcsection
---

# mxiris-reverse-engineering/machoobjcsection

A Swift library for parsing mach-o files to obtain Objecteve-C information.

## Usage

### Basic

Objective-C information from MachOImage or MachOFile can be retrieved via the `objc` property.

The protocol named [ObjCSectionRepresentable](./Sources/MachOObjCSection/Protocol/ObjCSectionRepresentable.swift) contains the objc information that can be retrieved.

```swift import MachOKit import MachOObjCSection

let machO //` MachOFile` or `MachOImage`

// image info let imageInfo = machO.objc.imageInfo

// objc classes(64bit) let classes = machO.objc.classes64 // objc classes(32bit) let classes = machO.objc.classes32

// objc protocols(64bit) let classes = machO.objc.protocols64 // objc protocols(32bit) let classes = machO.objc.protocols32

// objc category(64bit) let classes = machO.objc.categories64 // objc category(32bit) let classes = machO.objc.categories32 ```

### Detail

#### Class

The information that can be obtained about ObjC Class is summarized in [ObjCClassProtocol](./Sources/MachOObjCSection/Protocol/Class/ObjCClassProtocol.swift).

Details such as class names and method lists can be obtained from ro(read only) data. When retrieving from `MachOImage` in memory, it may be necessary to retrieve ro data via rw(read/write) data or further rw ext (read write external) data.

```swift let roData: ClassROData

if let _data = classROData(in: machO) {     roData = _data } else if let rw = classRWData(in: machO) {     if let _data = rw.classROData(in: machO) {         roData = _data     } else if let ext = rw.ext(in: machO),               let _data = ext.classROData(in: machO) {         roData = _data     } } ```

For example, to obtain a list of instance properties, write

```swift let instancePropertyList = roData.propertyList(in: machO)! for property in instancePropertyList.properties(in: machO) {     print("Name: \(property.name), Attributes: \(property.attributes)") } ```

To obtain a list of class properties or class methods, use metaclass.

```swift let meta = cls.metaClass(in: machO)! let roData: ClassROData64 = /* Get ro data from metaclass */ let classPropertyList = roData.propertyList(in: machO)! for property in classPropertyList.properties(in: machO) {     print("Name: \(property.name), Attributes: \(property.attributes)") } ```

#### Protocol

The information that can be obtained about ObjC Protocol is summarized in [ObjCProtocolProtocol](./Sources/MachOObjCSection/Protocol/Protocol/ObjCProtocolProtocol.swift).

#### Categories

The information that can be obtained about ObjC Protocol is summarized in [ObjCCategoryProtocol](./Sources/MachOObjCSection/Protocol/Category/ObjCCategoryProtocol.swift).

### Compatible with ObjCDump library

It is compatible with the library [ObjCDump](https://github.com/p-x9/swift-objc-dump) where models such as ObjC classes are defined. Conversion to ObjCDump models can be done via `info` properties and methods.

```swift // property let proeprtyInfo = property.info(isClassProperty: true) // ivar let ivarInfo = ivar.info(in: machO) // method let methodInfo = method.info(isClassMethod: true) // class let classInfo = cls.info(in: machO) // protocol let protocoInfo = proto.info(in: machO) // category let categoryInfo = category.info(in: machO) ```

#### Dump ObjC Header

ObjC header definitions can be retrieved from property/method/ivar/class/protocol/category model

```swift // property let header = propertyInfo.headerString // ivar let header = ivarInfo.headerString // method let header = methodInfo.headerString // class let header = classInfo.headerString // protocol let header = protocolInfo.headerString // category let header = categoryInfo.headerString ```

<details>

<summary>Example of dumped header string</summary>

```ObjectiveC @interface NSString : NSObject <NSItemProviderReading, NSItemProviderWriting, NSCopying, NSMutableCopying, NSSecureCoding>

@property(class, readonly, copy) NSArray *readableTypeIdentifiersForItemProvider; @property(class, readonly, copy) NSArray *writableTypeIdentifiersForItemProvider; @property(class, readonly) BOOL supportsSecureCoding;

@property(readonly, nonatomic) NSAttributedString *__baseAttributedString; @property(readonly) unsigned long long hash; @property(readonly) Class superclass; @property(readonly, copy) NSString *description; @property(readonly, copy) NSString *debugDescription; @property(readonly, copy) NSArray *writableTypeIdentifiersForItemProvider; @property(readonly, copy) NSString *stringByRemovingPercentEncoding; @property(readonly) unsigned long long length;

+ (id)allocWithZone:(struct _NSZone *)arg0; + (void)initialize; + (id)stringWithFormat:(id)arg0; + (id)stringWithUTF8String:(const char *)arg0; + (id)string; + (BOOL)_subclassesMustBeExplicitlyMentionedWhenDecoded; + (id)stringWithCharacters:(const unsigned short *)arg0 length:(unsigned long long)arg1; + (BOOL)supportsSecureCoding; + (id)stringWithCString:(const char *)arg0 encoding:(unsigned long long)arg1; + (id)stringWithString:(id)arg0; + (id)stringWithContentsOfFile:(id)arg0 encoding:(unsigned long long)arg1 error:(id *)arg2; + (id)stringWithContentsOfFile:(id)arg0 usedEncoding:(unsigned long long *)arg1 error:(id *)arg2; + (id)localizedStringWithValidatedFormat:(id)arg0 validFormatSpecifiers:(id)arg1 error:(id *)arg2; + (id)_newStringFromUTF16InternalData:(id)arg0 typeIdentifier:(id)arg1 error:(id *)arg2; + (id)_newZStringWithCharacters:(const unsigned short *)arg0 length:(unsigned long long)arg1; + (id)_newZStringWithString:(id)arg0; + (id)_newZStringWithUTF8String:(const char *)arg0; + (id)_scriptStringWithPropertyAccess:(unsigned long long)arg0; + (id)_scriptStringWithTabCount:(unsigned long long)arg0; + (id)_scriptingTextWithDescriptor:(id)arg0; + (id)_stringWithFormat:(id)arg0 locale:(id)arg1 options:(id)arg2 arguments:(char *)arg3; + (id)_web_stringRepresentationForBytes:(long long)arg0; + (const unsigned long long *)availableStringEncodings; + (unsigned long long)defaultCStringEncoding; + (id)localizedNameOfStringEncoding:(unsigned long long)arg0; + (id)localizedStringWithFormat:(id)arg0; + (id)objectWithItemProviderData:(id)arg0 typeIdentifier:(id)arg1 error:(id *)arg2; + (id)pathWithComponents:(id)arg0; + (id)readableTypeIdentifiersForItemProvider; + (unsigned long long)stringEncodingForData:(id)arg0 encodingOptions:(id)arg1 convertedString:(id *)arg2 usedLossyConversion:(BOOL *)arg3; + (id)stringWithBytes:(const void *)arg0 length:(unsigned long long)arg1 encoding:(unsigned long long)arg2; + (id)stringWithCString:(const char *)arg0; + (id)stringWithCString:(const char *)arg0 length:(unsigned long long)arg1; + (id)stringWithContentsOfFile:(id)arg0; + (id)stringWithContentsOfURL:(id)arg0; + (id)stringWithContentsOfURL:(id)arg0 encoding:(unsigned long long)arg1 error:(id *)arg2; + (id)stringWithContentsOfURL:(id)arg0 usedEncoding:(unsigned long long *)arg1 error:(id *)arg2; + (id)stringWithFormat:(id)arg0 locale:(id)arg1; + (id)stringWithValidatedFormat:(id)arg0 validFormatSpecifiers:(id)arg1 error:(id *)arg2; + (id)writableTypeIdentifiersForItemProvider;

- (id)copyWithZone:(struct _NSZone *)arg0; - (id)description; - (unsigned long long)hash; - (id)init; - (BOOL)isEqual:(id)arg0; - (id)mutableCopyWithZone:(struct _NSZone *)arg0; - (const char *)UTF8String; - (id)initWithUTF8String:(const char *)arg0; - (const char *)_fastCStringContents:(BOOL)arg0; - (double)doubleValue; - (float)floatValue; - (BOOL)getBytes:(void *)arg0 maxLength:(unsigned long long)arg1 usedLength:(unsigned long long *)arg2 encoding:(unsigned long long)arg3 options:(unsigned long long)arg4 range:(_NSRange)arg5 remainingRange:(struct _NSRange { unsigned long long x0; unsigned long long x1; } *)arg6; - (id)initWithFormat:(id)arg0 arguments:(char *)arg1; - (int)intValue; - (BOOL)isNSString__; - (unsigned long long)length; - (unsigned long long)lengthOfBytesUsingEncoding:(unsigned long long)arg0; - (long long)longLongValue; - (const char *)cString; - (unsigned long long)fastestEncoding; - (id)initWithString:(id)arg0; - (BOOL)_getCString:(char *)arg0 maxLength:(unsigned long long)arg1 encoding:(unsigned int)arg2; - (unsigned long long)_cfTypeID; - (id)_copyFormatStringWithConfiguration:(id)arg0; - (id)_createSubstringWithRange:(_NSRange)arg0; - (BOOL)_encodingCantBeStoredInEightBitCFString; - (const unsigned short *)_fastCharacterContents; - (unsigned int)_fastestEncodingInCFStringEncoding; - (BOOL)_isCString; - (id)_newSubstringWithRange:(_NSRange)arg0 zone:(struct _NSZone *)arg1; - (unsigned int)_pathResolveFlags; - (unsigned int)_queryResolveFlags; - (unsigned int)_smallestEncodingInCFStringEncoding; - (id)_stringRepresentation; - (id)_urlStringByInsertingPathResolveFlags:(unsigned int)arg0; - (id)_urlStringByInsertingQueryResolveFlags:(unsigned int)arg0; - (id)_urlStringByRemovingResolveFlags; - (BOOL)boolValue; - (unsigned long long)cStringLength; - (const char *)cStringUsingEncoding:(unsigned long long)arg0; - (unsigned short)characterAtIndex:(unsigned long long)arg0; - (Class)classForCoder; - (long long)compare:(id)arg0; - (long long)compare:(id)arg0 options:(unsigned long long)arg1 range:(_NSRange)arg2 locale:(id)arg3; - (id)dataUsingEncoding:(unsigned long long)arg0 allowLossyConversion:(BOOL)arg1; - (void)encodeWithCoder:(id)arg0; - (const char *)fileSystemRepresentation; - (id)formatConfiguration; - (BOOL)getCString:(char *)arg0 maxLength:(unsigned long long)arg1 encoding:(unsigned long long)arg2; - (void)getCharacters:(unsigned short *)arg0 range:(_NSRange)arg1; - (BOOL)getFileSystemRepresentation:(char *)arg0 maxLength:(unsigned long long)arg1; - (void)getLineStart:(unsigned long long *)arg0 end:(unsigned long long *)arg1 contentsEnd:(unsigned long long *)arg2 forRange:(_NSRange)arg3; - (void)getParagraphStart:(unsigned long long *)arg0 end:(unsigned long long *)arg1 contentsEnd:(unsigned long long *)arg2 forRange:(_NSRange)arg3; - (BOOL)hasPrefix:(id)arg0; - (BOOL)hasSuffix:(id)arg0; - (id)initWithCoder:(id)arg0; - (id)initWithContentsOfFile:(id)arg0; - (id)initWithContentsOfURL:(id)arg0; - (long long)integerValue; - (BOOL)isEqualToString:(id)arg0; - (id)lowercaseStringWithLocale:(id)arg0; - (_NSRange)rangeOfCharacterFromSet:(id)arg0 options:(unsigned long long)arg1 range:(_NSRange)arg2; - (unsigned long long)smallestEncoding; - (id)substringFromIndex:(unsigned long long)arg0; - (id)substringWithRange:(_NSRange)arg0; - (id)uppercaseStringWithLocale:(id)arg0; - (BOOL)containsString:(id)arg0; - (id)initWithFormat:(id)arg0; - (id)stringByAppendingPathComponent:(id)arg0; - (id)lowercaseString; - (id)stringByAppendingPathExtension:(id)arg0; - (id)capitalizedString; - (long long)caseInsensitiveCompare:(id)arg0; - (long long)compare:(id)arg0 options:(unsigned long long)arg1; - (id)componentsSeparatedByString:(id)arg0; - (id)dataUsingEncoding:(unsigned long long)arg0; - (id)initWithBytesNoCopy:(void *)arg0 length:(unsigned long long)arg1 encoding:(unsigned long long)arg2 freeWhenDone:(BOOL)arg3; - (id)initWithCString:(const char *)arg0 encoding:(unsigned long long)arg1; - (id)initWithCString:(const char *)arg0 length:(unsigned long long)arg1; - (id)initWithCharacters:(const unsigned short *)arg0 length:(unsigned long long)arg1; - (id)initWithData:(id)arg0 encoding:(unsigned long long)arg1; - (id)lastPathComponent; - (long long)localizedStandardCompare:(id)arg0; - (id)pathComponents; - (id)pathExtension; - (id)propertyList; - (_NSRange)rangeOfCharacterFromSet:(id)arg0; - (_NSRange)rangeOfCharacterFromSet:(id)arg0 options:(unsigned long long)arg1; - (_NSRange)rangeOfString:(id)arg0; - (_NSRange)rangeOfString:(id)arg0 options:(unsigned long long)arg1; - (_NSRange)rangeOfString:(id)arg0 options:(unsigned long long)arg1 range:(_NSRange)arg2; - (id)stringByAppendingFormat:(id)arg0; - (id)stringByAppendingString:(id)arg0; - (id)stringByApplyingTransform:(id)arg0 reverse:(BOOL)arg1; - (id)stringByDeletingLastPathComponent; - (id)stringByDeletingPathExtension; - (id)stringByExpandingTildeInPath; - (id)stringByReplacingCharactersInRange:(_NSRange)arg0 withString:(id)arg1; - (id)stringByReplacingOccurrencesOfString:(id)arg0 withString:(id)arg1; - (id)substringToIndex:(unsigned long long)arg0; - (id)stringByPaddingToLength:(unsigned long long)arg0 withString:(id)arg1 startingAtIndex:(unsigned long long)arg2; - (id)stringByStandardizingPath; - (id)uppercaseString; - (id)componentsSeparatedByCharactersInSet:(id)arg0; - (void)enumerateSubstringsInRange:(_NSRange)arg0 options:(unsigned long long)arg1 usingBlock:(id /* block */)arg2; - (void)getCharacters:(unsigned short *)arg0; - (id)initWithContentsOfFile:(id)arg0 encoding:(unsigned long long)arg1 error:(id *)arg2; - (_NSRange)rangeOfComposedCharacterSequenceAtIndex:(unsigned long long)arg0; - (id)stringByReplacingOccurrencesOfString:(id)arg0 withString:(id)arg1 options:(unsigned long long)arg2 range:(_NSRange)arg3; - (id)stringByTrimmingCharactersInSet:(id)arg0; - (BOOL)writeToFile:(id)arg0 atomically:(BOOL)arg1; - (id)_initWithFormat:(id)arg0 locale:(id)arg1 options:(id)arg2; - (id)_web_parseAsKeyValuePair_nowarn; - (id)commonPrefixWithString:(id)arg0 options:(unsigned long long)arg1; - (_NSRange)localizedStandardRangeOfString:(id)arg0; - (BOOL)matchesPattern:(id)arg0 caseInsensitive:(BOOL)arg1; - (id)__baseAttributedString; - (id)__escapeString5991; - (BOOL)__oldnf_containsChar:(BOOL)arg0; - (void)__oldnf_copyToUnicharBuffer:(unsigned short * *)arg0 saveLength:(long long *)arg1; - (BOOL)__swiftFillFileSystemRepresentationWithPointer:(char *)arg0 maxLength:(long long)arg1; - (_NSRange)significantText; - (id)stringByResolvingSymlinksInPath; - (id)_initWithDataOfUnknownEncoding:(id)arg0; - (id)_web_stringByTrimmingWhitespace; - (BOOL)isLike:(id)arg0; - (BOOL)matchesPattern:(id)arg0; - (id)__oldnf_componentsSeparatedBySet:(id)arg0; - (BOOL)__oldnf_containsCharFromSet:(id)arg0; - (BOOL)__oldnf_containsString:(id)arg0; - (id)__oldnf_stringWithSeparator:(unsigned short)arg0 atFrequency:(long long)arg1; - (id)stringByRemovingPercentEncoding; - (BOOL)_allowsDirectEncoding; - (id)_componentsSeparatedByCharactersInSet:(struct __CFCharacterSet *)arg0; - (void)_flushRegularExpressionCaches; - (void)_getBlockStart:(unsigned long long *)arg0 end:(unsigned long long *)arg1 contentsEnd:(unsigned long long *)arg2 forRange:(_NSRange)arg3 stopAtLineSeparators:(BOOL)arg4; - (id)_getBracketedStringFromBuffer:(struct _NSStringBuffer { unsigned long long x0; unsigned long long x1; id x2; unsigned long long x3; unsigned long long x4; unsigned short[32] x5; unsigned short x6; unsigned short x7; } *)arg0 string:(id)arg1; - (BOOL)_getBytesAsData:(id *)arg0 maxLength:(unsigned long long)arg1 usedLength:(unsigned long long *)arg2 encoding:(unsigned long long)arg3 options:(unsigned long long)arg4 range:(_NSRange)arg5 remainingRange:(struct _NSRange { unsigned long long x0; unsigned long long x1; } *)arg6; - (id)_getCharactersAsStringInRange:(_NSRange)arg0; - (id)_initWithBytesOfUnknownEncoding:(char *)arg0 length:(unsigned long long)arg1 copy:(BOOL)arg2 usedEncoding:(unsigned long long *)arg3; - (id)_initWithFormat:(id)arg0 locale:(id)arg1 options:(id)arg2 arguments:(char *)arg3; - (id)_initWithFormat:(id)arg0 options:(id)arg1; - (id)_initWithFormat:(id)arg0 options:(id)arg1 arguments:(char *)arg2; - (id)_initWithValidatedFormat:(id)arg0 validFormatSpecifiers:(id)arg1 locale:(id)arg2 options:(id)arg3 error:(id *)arg4; - (id)_initWithValidatedFormat:(id)arg0 validFormatSpecifiers:(id)arg1 locale:(id)arg2 options:(id)arg3 error:(id *)arg4 arguments:(char *)arg5; - (id)_initWithValidatedFormat:(id)arg0 validFormatSpecifiers:(id)arg1 options:(id)arg2 error:(id *)arg3; - (id)_initWithValidatedFormat:(id)arg0 validFormatSpecifiers:(id)arg1 options:(id)arg2 error:(id *)arg3 arguments:(char *)arg4; - (BOOL)_matchesCharacter:(unsigned short)arg0; - (_NSRange)_rangeOfCharacterFromSet:(struct __CFCharacterSet *)arg0 options:(unsigned long long)arg1 range:(_NSRange)arg2; - (_NSRange)_rangeOfRegularExpressionPattern:(id)arg0 options:(unsigned long long)arg1 range:(_NSRange)arg2 locale:(id)arg3; - (int)_scriptingAlternativeValueRankWithDescriptor:(id)arg0; - (id)_scriptingTextDescriptor; - (id)_stringByAddingPercentEncodingWithAllowedCharacters:(struct __CFCharacterSet *)arg0; - (id)_stringByReplacingOccurrencesOfRegularExpressionPattern:(id)arg0 withTemplate:(id)arg1 options:(unsigned long long)arg2 range:(_NSRange)arg3; - (id)_stringByResolvingSymlinksInPathUsingCache:(BOOL)arg0; - (id)_stringByStandardizingPathUsingCache:(BOOL)arg0; - (id)_stringByTrimmingCharactersInSet:(struct __CFCharacterSet *)arg0; - (id)_web_HTTPStyleLanguageCode; - (id)_web_HTTPStyleLanguageCodeWithoutRegion; - (id)_web_URLFragment; - (id)_web_characterSetFromContentTypeHeader_nowarn; - (long long)_web_countOfString:(id)arg0; - (id)_web_domainFromHost; - (BOOL)_web_domainMatches:(id)arg0; - (unsigned int)_web_extractFourCharCode; - (id)_web_fileNameFromContentDispositionHeader_nowarn; - (id)_web_filenameByFixingIllegalCharacters; - (id)_web_fixedCarbonPOSIXPath; - (BOOL)_web_hasCaseInsensitivePrefix:(id)arg0; - (BOOL)_web_hasCountryCodeTLD; - (BOOL)_web_isCaseInsensitiveEqualToString:(id)arg0; - (BOOL)_web_isFileURL; - (BOOL)_web_isJavaScriptURL; - (BOOL)_web_looksLikeAbsoluteURL; - (BOOL)_web_looksLikeIPAddress; - (id)_web_mimeTypeFromContentTypeHeader_nowarn; - (id)_web_parseAsKeyValuePairHandleQuotes_nowarn:(BOOL)arg0; - (_NSRange)_web_rangeOfURLHost; - (_NSRange)_web_rangeOfURLResourceSpecifier_nowarn; - (_NSRange)_web_rangeOfURLScheme_nowarn; - (_NSRange)_web_rangeOfURLUserPasswordHostPort; - (id)_web_splitAtNonDateCommas_nowarn; - (id)_web_stringByCollapsingNonPrintingCharacters; - (id)_web_stringByExpandingTildeInPath; - (id)_web_stringByReplacingValidPercentEscapes_nowarn; - (id)_widthVariants; - (BOOL)canBeConvertedToEncoding:(unsigned long long)arg0; - (id)capitalizedStringWithLocale:(id)arg0; - (long long)compare:(id)arg0 options:(unsigned long long)arg1 range:(_NSRange)arg2; - (unsigned long long)completePathIntoString:(id *)arg0 caseSensitive:(BOOL)arg1 matchesIntoArray:(id *)arg2 filterTypes:(id)arg3; - (struct { int x0 : 8; int x1 : 4; int x2 : 1; int x3 : 1; int x4 : 18; unsigned short[8] x5; })decimalValue; - (id)decomposedStringWithCanonicalMapping; - (id)decomposedStringWithCompatibilityMapping; - (id)displayableString; - (void)enumerateLinesUsingBlock:(id /* block */)arg0; - (void)enumerateLinguisticTagsInRange:(_NSRange)arg0 scheme:(id)arg1 options:(unsigned long long)arg2 orthography:(id)arg3 usingBlock:(id /* block */)arg4; - (BOOL)getBytes:(char *)arg0 maxLength:(unsigned long long)arg1 filledLength:(unsigned long long *)arg2 encoding:(unsigned long long)arg3 allowLossyConversion:(BOOL)arg4 range:(_NSRange)arg5 remainingRange:(struct _NSRange { unsigned long long x0; unsigned long long x1; } *)arg6; - (void)getCString:(char *)arg0; - (void)getCString:(char *)arg0 maxLength:(unsigned long long)arg1; - (void)getCString:(char *)arg0 maxLength:(unsigned long long)arg1 range:(_NSRange)arg2 remainingRange:(struct _NSRange { unsigned long long x0; unsigned long long x1; } *)arg3; - (BOOL)getExternalRepresentation:(id *)arg0 extendedAttributes:(id *)arg1 forWritingToURLOrPath:(id)arg2 usingEncoding:(unsigned long long)arg3 error:(id *)arg4; - (id)initWithBytesNoCopy:(void *)arg0 length:(unsigned long long)arg1 encoding:(unsigned long long)arg2 deallocator:(id /* block */)arg3; - (id)initWithCString:(const char *)arg0; - (id)initWithCStringNoCopy:(char *)arg0 length:(unsigned long long)arg1 freeWhenDone:(BOOL)arg2; - (id)initWithCharactersNoCopy:(unsigned short *)arg0 length:(unsigned long long)arg1 deallocator:(id /* block */)arg2; - (id)initWithCharactersNoCopy:(unsigned short *)arg0 length:(unsigned long long)arg1 freeWhenDone:(BOOL)arg2; - (id)initWithContentsOfFile:(id)arg0 usedEncoding:(unsigned long long *)arg1 error:(id *)arg2; - (id)initWithContentsOfURL:(id)arg0 encoding:(unsigned long long)arg1 error:(id *)arg2; - (id)initWithContentsOfURL:(id)arg0 usedEncoding:(unsigned long long *)arg1 error:(id *)arg2; - (id)initWithData:(id)arg0 usedEncoding:(unsigned long long *)arg1; - (id)initWithFormat:(id)arg0 locale:(id)arg1; - (id)initWithFormat:(id)arg0 locale:(id)arg1 arguments:(char *)arg2; - (id)initWithValidatedFormat:(id)arg0 validFormatSpecifiers:(id)arg1 arguments:(char *)arg2 error:(id *)arg3; - (id)initWithValidatedFormat:(id)arg0 validFormatSpecifiers:(id)arg1 error:(id *)arg2; - (id)initWithValidatedFormat:(id)arg0 validFormatSpecifiers:(id)arg1 locale:(id)arg2 arguments:(char *)arg3 error:(id *)arg4; - (id)initWithValidatedFormat:(id)arg0 validFormatSpecifiers:(id)arg1 locale:(id)arg2 error:(id *)arg3; - (BOOL)isAbsolutePath; - (BOOL)isCaseInsensitiveLike:(id)arg0; - (_NSRange)lineRangeForRange:(_NSRange)arg0; - (id)linguisticTagsInRange:(_NSRange)arg0 scheme:(id)arg1 options:(unsigned long long)arg2 orthography:(id)arg3 tokenRanges:(id *)arg4; - (id)loadDataWithTypeIdentifier:(id)arg0 forItemProviderCompletionHandler:(id /* block */)arg1; - (id)localizedCapitalizedString; - (long long)localizedCaseInsensitiveCompare:(id)arg0; - (BOOL)localizedCaseInsensitiveContainsString:(id)arg0; - (long long)localizedCompare:(id)arg0; - (BOOL)localizedHasPrefix:(id)arg0; - (BOOL)localizedHasSuffix:(id)arg0; - (id)localizedLowercaseString; - (BOOL)localizedStandardContainsString:(id)arg0; - (id)localizedUppercaseString; - (const char *)lossyCString; - (unsigned long long)maximumLengthOfBytesUsingEncoding:(unsigned long long)arg0; - (_NSRange)paragraphRangeForRange:(_NSRange)arg0; - (id)precomposedStringWithCanonicalMapping; - (id)precomposedStringWithCompatibilityMapping; - (id)propertyListFromStringsFileFormat; - (id)quotedStringRepresentation; - (_NSRange)rangeOfComposedCharacterSequencesForRange:(_NSRange)arg0; - (_NSRange)rangeOfString:(id)arg0 options:(unsigned long long)arg1 range:(_NSRange)arg2 locale:(id)arg3; - (id)replacementObjectForPortCoder:(id)arg0; - (BOOL)scriptingBeginsWith:(id)arg0; - (BOOL)scriptingContains:(id)arg0; - (BOOL)scriptingEndsWith:(id)arg0; - (BOOL)scriptingIsEqualTo:(id)arg0; - (BOOL)scriptingIsGreaterThan:(id)arg0; - (BOOL)scriptingIsGreaterThanOrEqualTo:(id)arg0; - (BOOL)scriptingIsLessThan:(id)arg0; - (BOOL)scriptingIsLessThanOrEqualTo:(id)arg0; - (id)standardizedURLPath; - (id)stringByAbbreviatingWithTildeInPath; - (id)stringByAddingPercentEncodingWithAllowedCharacters:(id)arg0; - (id)stringByAddingPercentEscapes; - (id)stringByAddingPercentEscapesUsingEncoding:(unsigned long long)arg0; - (id)stringByConvertingPathToURL; - (id)stringByConvertingURLToPath; - (id)stringByFoldingWithOptions:(unsigned long long)arg0 locale:(id)arg1; - (id)stringByRemovingPercentEscapes; - (id)stringByReplacingPercentEscapesUsingEncoding:(unsigned long long)arg0; - (id)stringMarkingUpcaseTransitionsWithDelimiter2:(id)arg0; - (id)stringsByAppendingPaths:(id)arg0; - (id)variantFittingPresentationWidth:(long long)arg0; - (id)writableTypeIdentifiersForItemProvider; - (BOOL)writeToFile:(id)arg0 atomically:(BOOL)arg1 encoding:(unsigned long long)arg2 error:(id *)arg3; - (BOOL)writeToURL:(id)arg0 atomically:(BOOL)arg1; - (BOOL)writeToURL:(id)arg0 atomically:(BOOL)arg1 encoding:(unsigned long long)arg2 error:(id *)arg3;

@end ```

</details>

## Rendering and Indexing

The `MachOObjCSection` library above parses metadata. Three further products turn that metadata into readable declarations. They layer on top of each other, so depend on the highest one you need:

``` MachOObjCSection          parsing only         ↑ ObjCMetadataSource        one generic entry point onto MachOFile and MachOImage alike         ↑ ObjCDeclarationRendering  ObjCClassInfo & co. → SemanticString         ↑ ObjCIndexing              per-binary index; broadcasts inheritance / conformance         ↑ ObjCInterface             strip filtering + rendering entry point ```

Everything above `ObjCMetadataSource` works the same whether you hand it a `MachOFile` read off disk — any architecture, any platform, inside a dyld shared cache or standalone — or a `MachOImage` already mapped into this process. See [Files versus loaded images](#files-versus-loaded-images).

Unlike `ObjCDump`'s plain-text `headerString`, the rendered output is a `SemanticString` from [swift-semantic-string](https://github.com/MxIris-Reverse-Engineering/swift-semantic-string): every token keeps its kind, so it can be syntax-coloured, rewritten token-by-token, or annotated with offsets and IMP addresses.

### ObjCInterface

The usual entry point. Index an image once, then ask for declarations:

```swift import MachOKit import ObjCIndexing import ObjCInterface

let machO = MachOImage(name: "Foundation")!

let indexer = ObjCInterfaceIndexer(machO: machO, imagePath: machO.imagePath) try await indexer.prepare()

let builder = ObjCInterfaceBuilder(indexer: indexer, machO: machO) print(builder.classInterface(named: "NSString")?.string ?? "") ```

`ObjCGenerationOptions` carries ten switches — six that strip members, four that add explanatory comments:

```swift var options = ObjCGenerationOptions.default options.stripSynthesizedMethods = true   // drop @property-synthesized accessors options.addIvarOffsetComments = true     // append `// offset: …` to each ivar options.addMethodIMPAddressComments = true

let declaration = builder.classInterface(named: "NSError", options: options) ```

C primitive types can be substituted, and the ivar-offset comment reworded:

```swift let declaration = builder.classInterface(     named: "NSError",     options: options,     cTypeReplacements: [.ulongLong: "NSUInteger", .double: "CGFloat"],     ivarOffsetCommentBuilder: { "at 0x\(String($0, radix: 16, uppercase: true))" } ) ```

`protocolInterface(named:)`, `categoryInterface(uniqueName:)`, `structInterface(named:)` and `unionInterface(named:)` round out the API.

### Files versus loaded images

The same code reads a binary off disk — pass a `MachOFile` instead of a `MachOImage`:

```swift import MachOKit import ObjCIndexing import ObjCInterface

let machOFile = try MachOFile(url: URL(fileURLWithPath: "/path/to/Some.framework/Some"))

let indexer = ObjCInterfaceIndexer(machO: machOFile, imagePath: machOFile.imagePath) try await indexer.prepare()

let builder = ObjCInterfaceBuilder(indexer: indexer, machO: machOFile) print(builder.classInterface(named: "SomeClass")?.string ?? "") ```

The generic parameter is inferred from the argument, so existing call sites need no change. Places that *spell the type out* — a stored property, a declared return type — do: `ObjCInterfaceIndexer` becomes `ObjCInterfaceIndexer<MachOImage>`.

Two differences between the modes are worth knowing before you trust the output:

- **A superclass chain read from a standalone file stops at the first superclass defined in   another binary.** File mode can follow a superclass across binaries only within one dyld   shared cache; a loaded image has every dependency mapped in and walks to the root class.   `stripOverrides` works off that chain, so it strips less in file mode. - **`classRWData` / `hasRWPointer` stay off the generic interface.** RW data is written by the   Objective-C runtime when it realizes a class, so it does not exist in a file at all.   Exposing them generically would only create an interface that always returns `nil` in file   mode. Callers that need them keep to the `MachOImage`-specific path.

## Command Line

`objc-section` exposes the same layers as a command-line tool, so a binary can be dumped without loading it into a process — including binaries for another architecture or platform.

```bash swift build -c release --product objc-section ```

```bash # Every Objective-C declaration in a binary objc-section dump /path/to/Some.framework/Some

# One declaration objc-section interface NSString /path/to/Some.framework/Some

# An image inside a dyld shared cache objc-section dump /path/to/dyld_shared_cache_arm64e --dyld-shared-cache -n Foundation objc-section interface NSError --uses-system-dyld-shared-cache -n Foundation

# A fat binary needs an architecture objc-section dump /path/to/Universal -a arm64e ```

Each of the ten `ObjCGenerationOptions` switches has a flag, and all of them default to off, so a bare `dump` prints the metadata as it stands:

```bash objc-section interface ACAssetSymbolGeneratorOptions ./AssetCatalogFoundation \   --strip-synthesized-methods --strip-dtor-method \   --emit-ivar-offsets --emit-method-imp-addresses \   --c-type-replacement "long long=NSInteger" ```

```objc @interface ACAssetSymbolGeneratorOptions : NSObject {     NSInteger targetPlatform; // offset: 8     BOOL generateExtensions; // offset: 16     ... }

@property (nonatomic, readonly) NSInteger targetPlatform; ...

- (id)init; // IMP: 0x10B400

@end ```

Other options: `-s/--sections` to pick declaration kinds, `-f/--filter` to match names, `-o/--output-path` to write a file, `-c/--color-scheme` for terminal colours, and `-v/--verbose` to report indexing progress on stderr.

### API diffing: snapshot / diff / evolution

Three more subcommands compare the ObjC API surface across binaries — the counterpart of `swift-section`'s ABI commands, with identical option spelling. Any input can be a Mach-O / fat binary, a dyld shared cache (with `--dyld-shared-cache -n <image>`), or a baseline JSON produced by `snapshot`; the two are distinguished automatically.

```bash # Freeze a binary's ObjC API as a persistable baseline (indexing is the slow part; # comparisons against the JSON later need no original binary) objc-section snapshot 15.5/dyld_shared_cache_arm64e --dyld-shared-cache -n CoreLocation \   --label 15.5 -o CoreLocation-15.5.json

# Structured diff: classes / protocols / categories, with methods, properties, ivars, # protocol adoptions and superclass changes classified as added / removed / modified objc-section diff CoreLocation-15.5.json CoreLocation-26.5.json

# Track every declaration's lifeline across N ordered versions objc-section evolution CoreLocation-*.json --labels 15.5,26.0,26.5 --summary-only ```

Both `diff` and `evolution` support `--json` for structured output, `--summary-only` for just the verdict, `--fail-on-breaking` to exit nonzero on an API-breaking change (CI gating), and `-o` to write the report to a file. The engine lives in the `ObjCDiffing` library product (`ObjCAPIDiffer` / `ObjCAPIEvolutionBuilder` / `ObjCAPISnapshotDocument`), usable directly from Swift via `ObjCAPISnapshotBuilder` in `ObjCInterface`.

Baselines carry a `formatVersion` header. The identity/payload key scheme is the de-facto persistence format, so a baseline written by a different format version is rejected with a clear error instead of being silently mis-compared — regenerate it with the current tool.

> [!NOTE] > Reading an image out of a **macOS 26** dyld shared cache needs MachOKit 0.52.101 or newer, > which this package already requires. Earlier versions resolve the objc header-info offsets > against the subcache holding the optimization structure rather than the one holding the > image, so the objc image index never resolves and the output silently comes back with ivars > but no methods, properties or protocols. Fixed by > [p-x9/MachOKit#310](https://github.com/p-x9/MachOKit/pull/310).

### ObjCIndexing

Use it directly when you want the index itself rather than rendered text — the class, protocol, category, struct and union names an image defines:

```swift indexer.classNames indexer.protocolNames indexer.classGroup(forName: "NSMutableString") ```

Inheritance and protocol adoption are **not** stored. The indexer reports them as it walks, through the same `eventHandler` that carries progress, and folding them into whatever shape you need is yours to do. Keeping those reverse tables eagerly cost time and memory proportional to an image's class and category count — a bill every caller paid, including the ones that only ever rendered a single declaration:

```swift var subclassesByClassName: [String: [String]] = [:]

let indexer = ObjCInterfaceIndexer(machO: machO, imagePath: machO.imagePath) { event in     switch event {     case .subclassIndexed(let className, let superclass, _, _):         subclassesByClassName[superclass, default: []].append(className)     case .progress(let phase, _, let current, let total):         print("\(phase) \(current)/\(total)")     default:         break     } }

try await indexer.prepare() ```

Two properties of that stream are worth knowing before you rely on it:

- **Relationship data travels only through the handler.** An indexer built without one keeps   no record of inheritance or adoption in any form. Omitting it while expecting relationships   fails silently — the code compiles, the walk runs, the relationships are simply gone. - **Emission order is deterministic.** Every class-phase event precedes every category-phase   event, classes follow the `__objc_classlist` walk, and each class reports its superclass   before its adopted protocols. Accumulating in arrival order therefore reproduces the   binary's declaration order. Changing that order would be a breaking change; the execution   context the handler runs on, by contrast, is deliberately not promised.

### ObjCDeclarationRendering

The bottom layer, for callers that already hold `ObjCClassInfo` / `ObjCProtocolInfo` / `ObjCCategoryInfo` values and only want them rendered:

```swift import ObjCDeclarationRendering

let context = ObjCRenderingContext(machO: machO, options: options) let declaration = classInfo.semanticString(using: context) ```

## License

MachOObjCSection is released under the MIT License. See [LICENSE](./LICENSE)

## Package Metadata

Repository: mxiris-reverse-engineering/machoobjcsection

Default branch: main

README: README.md