Source/CDObjectiveCProcessor.m

// -*- mode: ObjC -*-

//  This file is part of class-dump, a utility for examining the Objective-C segment of Mach-O files.
//  Copyright (C) 1997-1998, 2000-2001, 2004-2012 Steve Nygard.

#import "CDObjectiveCProcessor.h"

#import "CDClassDump.h"
#import "CDMachOFile.h"
#import "CDVisitor.h"
#import "CDLCSegment.h"
#import "CDLCDynamicSymbolTable.h"
#import "CDLCSymbolTable.h"
#import "CDOCProtocol.h"
#import "CDTypeController.h"
#import "CDOCClass.h"
#import "CDOCCategory.h"
#import "CDSection.h"

// Note: sizeof(long long) == 8 on both 32-bit and 64-bit.  sizeof(uint64_t) == 8.  So use [NSNumber numberWithUnsignedLongLong:].

@implementation CDObjectiveCProcessor
{
    CDMachOFile *_machOFile;
    
    NSMutableArray *_classes;
    NSMutableDictionary *_classesByAddress;
    
    NSMutableArray *_categories;
    
    NSMutableDictionary *_protocolsByName; // uniqued
    NSMutableDictionary *_protocolsByAddress; // non-uniqued
}

- (id)initWithMachOFile:(CDMachOFile *)machOFile;
{
    if ((self = [super init])) {
        _machOFile = machOFile;
        _classes = [[NSMutableArray alloc] init];
        _classesByAddress = [[NSMutableDictionary alloc] init];
        _categories = [[NSMutableArray alloc] init];
        _protocolsByName = [[NSMutableDictionary alloc] init];
        _protocolsByAddress = [[NSMutableDictionary alloc] init];
    }

    return self;
}

#pragma mark - Debugging

- (NSString *)description;
{
    return [NSString stringWithFormat:@"<%@:%p> machOFile: %@",
            NSStringFromClass([self class]), self,
            self.machOFile.filename];
}

#pragma mark -

- (BOOL)hasObjectiveCData;
{
    return self.machOFile.hasObjectiveC1Data || self.machOFile.hasObjectiveC2Data;
}

- (CDSection *)objcImageInfoSection;
{
    // Implement in subclasses.
    return nil;
}

- (NSString *)garbageCollectionStatus;
{
    if (self.objcImageInfoSection != nil) {
        // The SDK frameworks (i.e. within Xcode, not in /System) have empty sections.
        if (self.objcImageInfoSection.size < 8)
            return @"Unknown";

        CDMachOFileDataCursor *cursor = [[CDMachOFileDataCursor alloc] initWithSection:self.objcImageInfoSection];
        
        [cursor readInt32];
        uint32_t v2 = [cursor readInt32];
        //NSLog(@"%s: %08x %08x", __cmd, v1, v2);
        // v2 == 0 -> Objective-C Garbage Collection: Unsupported
        // v2 == 2 -> Supported
        // v2 == 6 -> Required
        //NSParameterAssert(v2 == 0 || v2 == 2 || v2 == 6);
        
        // See markgc.c in the objc4 project
        switch (v2 & 0x06) {
            case 0: return @"Unsupported";
            case 2: return @"Supported";
            case 6: return @"Required";
        }
        
        return [NSString stringWithFormat:@"Unknown (0x%08x)", v2];
    }
    
    return nil;
}

#pragma mark -

- (void)addClass:(CDOCClass *)aClass withAddress:(uint64_t)address;
{
    [_classes addObject:aClass];
    [_classesByAddress setObject:aClass forKey:[NSNumber numberWithUnsignedLongLong:address]];
}

- (CDOCClass *)classWithAddress:(uint64_t)address;
{
    return [_classesByAddress objectForKey:[NSNumber numberWithUnsignedLongLong:address]];
}

- (void)addClassesFromArray:(NSArray *)array;
{
    if (array != nil)
        [_classes addObjectsFromArray:array];
}

- (void)addCategoriesFromArray:(NSArray *)array;
{
    if (array != nil)
        [_categories addObjectsFromArray:array];
}

- (CDOCProtocol *)protocolWithAddress:(uint64_t)address;
{
    NSNumber *key = [NSNumber numberWithUnsignedLongLong:address];
    return _protocolsByAddress[key];
}

- (void)setProtocol:(CDOCProtocol *)protocol withAddress:(uint64_t)address;
{
    NSNumber *key = [NSNumber numberWithUnsignedLongLong:address];
    _protocolsByAddress[key] = protocol;
}

- (CDOCProtocol *)protocolForName:(NSString *)name;
{
    return _protocolsByName[name];
}

- (void)addCategory:(CDOCCategory *)category;
{
    if (category != nil)
        [_categories addObject:category];
}

#pragma mark - Processing

- (void)process;
{
    if (self.machOFile.isEncrypted == NO && self.machOFile.canDecryptAllSegments) {
        [self.machOFile.symbolTable loadSymbols];
        [self.machOFile.dynamicSymbolTable loadSymbols];

        [self loadProtocols];

        // Load classes before categories, so we can get a dictionary of classes by address.
        [self loadClasses];
        [self loadCategories];
    }
}

- (void)loadProtocols;
{
    // Implement in subclasses.
}

- (void)loadClasses;
{
    // Implement in subclasses.
}

- (void)loadCategories;
{
    // Implement in subclasses.
}


- (void)registerTypesWithObject:(CDTypeController *)typeController phase:(NSUInteger)phase;
{
    for (CDOCClass *aClass in _classes)
        [aClass registerTypesWithObject:typeController phase:phase];

    for (CDOCCategory *category in _categories)
        [category registerTypesWithObject:typeController phase:phase];

    for (NSString *name in [[_protocolsByName allKeys] sortedArrayUsingSelector:@selector(compare:)])
        [_protocolsByName[name] registerTypesWithObject:typeController phase:phase];
}

- (void)recursivelyVisit:(CDVisitor *)visitor;
{
    NSMutableArray *classesAndCategories = [[NSMutableArray alloc] init];
    [classesAndCategories addObjectsFromArray:_classes];
    [classesAndCategories addObjectsFromArray:_categories];

    // TODO: Sort protocols by dependency
    // TODO (2004-01-30): It looks like protocols might be defined in more than one file.  i.e. NSObject.
    // TODO (2004-02-02): Looks like we need to record the order the protocols were encountered, or just always sort protocols
    NSArray *protocolNames = [[_protocolsByName allKeys] sortedArrayUsingSelector:@selector(compare:)];

    [visitor willVisitObjectiveCProcessor:self];
    [visitor visitObjectiveCProcessor:self];

    for (NSString *protocolName in protocolNames) {
        [_protocolsByName[protocolName] recursivelyVisit:visitor];
    }

    if ([[visitor classDump] shouldSortClassesByInheritance]) {
        [classesAndCategories sortTopologically];
    } else if ([[visitor classDump] shouldSortClasses])
        [classesAndCategories sortUsingSelector:@selector(ascendingCompareByName:)];

    for (id aClassOrCategory in classesAndCategories)
        [aClassOrCategory recursivelyVisit:visitor];

    [visitor didVisitObjectiveCProcessor:self];
}

- (void)createUniquedProtocols;
{
    // Now unique the protocols by name and store in protocolsByName

    for (NSNumber *key in [[_protocolsByAddress allKeys] sortedArrayUsingSelector:@selector(compare:)]) {
        CDOCProtocol *p1 = _protocolsByAddress[key];
        CDOCProtocol *p2 = _protocolsByName[p1.name];
        if (p2 == nil) {
            p2 = [[CDOCProtocol alloc] init];
            [p2 setName:[p1 name]];
            _protocolsByName[p2.name] = p2;
            // adopted protocols still not set, will want uniqued instances
        } else {
        }
    }

    //NSLog(@"uniqued protocol names: %@", [[[protocolsByName allKeys] sortedArrayUsingSelector:@selector(compare:)] componentsJoinedByString:@", "]);

    // And finally fill in adopted protocols, instance and class methods.  And properties.
    for (NSNumber *key in [[_protocolsByAddress allKeys] sortedArrayUsingSelector:@selector(compare:)]) {
        CDOCProtocol *p1 = _protocolsByAddress[key];
        CDOCProtocol *uniqueProtocol = _protocolsByName[p1.name];
        for (CDOCProtocol *p2 in [p1 protocols])
            [uniqueProtocol addProtocol:_protocolsByName[p2.name]];

        if ([[uniqueProtocol classMethods] count] == 0) {
            for (CDOCMethod *method in [p1 classMethods])
                [uniqueProtocol addClassMethod:method];
        } else {
            NSParameterAssert([[p1 classMethods] count] == 0 || [[uniqueProtocol classMethods] count] == [[p1 classMethods] count]);
        }

        if ([[uniqueProtocol instanceMethods] count] == 0) {
            for (CDOCMethod *method in [p1 instanceMethods])
                [uniqueProtocol addInstanceMethod:method];
        } else {
            if (!([[p1 instanceMethods] count] == 0 || [[uniqueProtocol instanceMethods] count] == [[p1 instanceMethods] count])) {
                //NSLog(@"p1 name: %@, uniqueProtocol name: %@", [p1 name], [uniqueProtocol name]);
                //NSLog(@"p1 instanceMethods: %@", [p1 instanceMethods]);
                //NSLog(@"uniqueProtocol instanceMethods: %@", [uniqueProtocol instanceMethods]);
            }
            NSParameterAssert([[p1 instanceMethods] count] == 0 || [[uniqueProtocol instanceMethods] count] == [[p1 instanceMethods] count]);
        }

        if ([[uniqueProtocol optionalClassMethods] count] == 0) {
            for (CDOCMethod *method in [p1 optionalClassMethods])
                [uniqueProtocol addOptionalClassMethod:method];
        } else {
            NSParameterAssert([[p1 optionalClassMethods] count] == 0 || [[uniqueProtocol optionalClassMethods] count] == [[p1 optionalClassMethods] count]);
        }

        if ([[uniqueProtocol optionalInstanceMethods] count] == 0) {
            for (CDOCMethod *method in [p1 optionalInstanceMethods])
                [uniqueProtocol addOptionalInstanceMethod:method];
        } else {
            NSParameterAssert([[p1 optionalInstanceMethods] count] == 0 || [[uniqueProtocol optionalInstanceMethods] count] == [[p1 optionalInstanceMethods] count]);
        }

        if ([[uniqueProtocol properties] count] == 0) {
            for (CDOCProperty *property in [p1 properties])
                [uniqueProtocol addProperty:property];
        } else {
            NSParameterAssert([[p1 properties] count] == 0 || [[uniqueProtocol properties] count] == [[p1 properties] count]);
        }
    }

    //NSLog(@"protocolsByName: %@", protocolsByName);
}

@end