Symbolicator.mm

//
//  Symbolicator.m
//  Symbolicator
//
//  Created by Eric Castro on 13/02/13.
//
//

#import "AppSupport/AppSupport.h"

#include <mach/mach.h>
#include <objc/runtime.h>
#include <sys/time.h>

#import "Symbolicator.h"

#define kSCSymbolsRequest @"SCSymbolsRequest"
#define kSCMessagingCenterName @"ro.cast.eric.Symbolicator"

MethodEntry *createMethodEntry(unsigned imp, const char *className,const char *methodName, BOOL isClassMethod)
{
    MethodEntry *entry = (MethodEntry *)malloc(sizeof(MethodEntry));
    entry->imp = imp;
    entry->name[0] = NO ? '+' : '-';
    entry->name[1] = '[';
    strcpy(entry->name+2,className);
    entry->name[strlen(className)+2] = ' ';
    strcpy(entry->name+strlen(className)+3,methodName);
    strcpy(entry->name+strlen(className)+strlen(methodName)+3,"]");

    return entry;
}

@implementation Symbolicator

- (id)init
{
    self = [super init];
    if (self) {

        _symbolicator = [[VMUSymbolicator symbolicatorForTask:mach_task_self()] retain];
        _processInfo = [[VMUProcessDescription alloc] initWithPid:0 orTask:mach_task_self()];
        _machContainer = [[VMUMachTaskContainer machTaskContainerWithTask:mach_task_self()] retain];

        dispatch_async(dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
            [self load];
        });

    }
    return self;
}

- (void) load
{
    NSLog(@"Symbolicator: Loading all methods addresses from objc runtime");

    int numClasses;
    unsigned int numInstanceMethods;
    unsigned int numClassMethods;
    Class * classes = NULL;
    Method * instanceMethods = NULL;
    Method * classMethods = NULL;

    classes = NULL;
    char className[128];
    numClasses = objc_getClassList(NULL, 0);

    unsigned int imp;

    _maxAddress = 0;
    _minAddress = 2^32;

    timeval time1, time2;
    gettimeofday(&time1, NULL);
    long millis1 = (time1.tv_sec * 1000) + (time1.tv_usec / 1000);

    MethodEntry *entry;
    if (numClasses > 0)
    {
        classes = (Class *)malloc(sizeof(Class) * numClasses);
        numClasses = objc_getClassList(classes, numClasses);

        for (int i=0;i<numClasses;i++)
        {
            classMethods = class_copyMethodList(objc_getMetaClass(class_getName(classes[i])), &numClassMethods);
            instanceMethods = class_copyMethodList(classes[i], &numInstanceMethods);

            for (int j=0; j<numClassMethods; j++) {
                imp = (NSUInteger)method_getImplementation(classMethods[j]);
                entry = createMethodEntry(imp, class_getName(classes[i]), sel_getName(method_getName(classMethods[j])), YES);

                HASH_ADD_INT(_methodList, imp, entry);

                if (imp > _maxAddress) _maxAddress = imp;
                if (imp < _minAddress) _minAddress = imp;
            }

            for (int j=0; j<numInstanceMethods; j++) {
                imp = (NSUInteger)method_getImplementation(instanceMethods[j]);
                entry = createMethodEntry(imp, class_getName(classes[i]), sel_getName(method_getName(instanceMethods[j])), NO);

                HASH_ADD_INT(_methodList, imp, entry);

                if (imp > _maxAddress) _maxAddress = imp;
                if (imp < _minAddress) _minAddress = imp;
            }

            free(classMethods);
            free(instanceMethods);
        }

        free(classes);
    }

    gettimeofday(&time2, NULL);
    long millis2 = (time2.tv_sec * 1000) + (time2.tv_usec / 1000);

    NSLog(@"Symbolicator: All addresses loaded and sorted %ld milliseconds",millis2-millis1);//-millis1/1000.0);

}

- (NSDictionary *)symbolicateAddresses:(NSArray *)addresses
{
    NSMutableDictionary *response = [NSMutableDictionary dictionaryWithCapacity:addresses.count];

    NSString *hexAddress;

    NSString *methodName;
    unsigned long long longLongAddress;

    // Try to get the symbols for all requested addresses
    for (NSNumber *address in addresses)
    {
        longLongAddress = [address unsignedLongLongValue];
        hexAddress = [NSString stringWithFormat:@"0x%08llx",longLongAddress];


        methodName = [self findMethod:address slide:[self slideForAddress:longLongAddress]];
        if (methodName)
        {
            response[hexAddress] = methodName;
            continue;
        }

        VMUSymbol *symbol = [_symbolicator symbolForAddress:longLongAddress];

        if ([symbol name])
            response[hexAddress] = [symbol name];

    }

    return response;
}

- (NSString *)findMethod:(NSNumber *)address slide:(unsigned)slide
{
    unsigned int newAddress = [address unsignedIntValue];
    unsigned searchCount = 0;

    struct MethodEntry *entry;

    do {

        entry = NULL;
        HASH_FIND_INT( _methodList, &newAddress, entry );

        if (entry)
            return [NSString stringWithFormat:@"(0x%08x): %s", newAddress-slide-1, entry->name];

        searchCount++;

        if (searchCount > 8096)
            return [NSString stringWithFormat:@"(0x%08x):", [address unsignedIntValue]-slide-1];

        newAddress = newAddress-1;

    } while (newAddress!=_minAddress);

    return nil;
}

- (unsigned)slideForAddress:(unsigned long long)address
{
    VMUMemory_NonContiguousTask *memory;
    VMUMachOHeader *header;
    VMURange range;
    unsigned long long textStart;

    for (NSDictionary *image in _processInfo.binaryImages)
    {
        range.location = [image[@"StartAddress"] unsignedLongLongValue];
        range.length = [image[@"Size"] unsignedLongLongValue];

        if (address >= range.location &&
            address <= range.location+range.length)
        {
            memory = [VMUMemory_NonContiguousTask memoryWithMachTaskContainer:_machContainer addressRange:range architecture:[VMUArchitecture armArchitecture]];
            header = [VMUMachOHeader headerWithMemory:memory address:range.location name:image[@"Identifier"] path:image[@"ExecutablePath"] timestamp:[NSDate date]];
            textStart = [[header segmentNamed:@"__TEXT"] vmaddr];

            return range.location-textStart;
        }
    }
    return 0;
}



@end

// Replacement for _NSCallStackArray - imitates the exact same output when printed with NSLog

@implementation SCCallStackArray

+ (id)arrayWithCallStack:(NSArray *)array
{
    return [[[SCCallStackArray alloc] initWithCallStack:array] autorelease];
}

- (id)initWithCallStack:(NSArray *)array
{
    self = [super init];
    if (self) {
        _descriptions = [[NSMutableArray alloc] initWithCapacity:[array count]];

        NSString *pos, *nextpos;

        for (int i=0;i<[array count];i++) //fugly stuff - must eliminate first line (that's Symbolicator's call you don't need) and preserve the numbers with the correct spacing
        {
//            pos = [array[i] componentsSeparatedByString:@" "][0];
//            nextpos = [array[i+1] componentsSeparatedByString:@" "][0];
//            _descriptions[i] = [NSString stringWithFormat:@"%@ %@",pos,[array[i+1] substringFromIndex:[nextpos length]]];

            _descriptions[i] = array[i];
        }
    }

    return self;
}

- (NSUInteger)count
{
    return [_descriptions count];
}

- (id)objectAtIndex:(NSUInteger)index
{
    return _descriptions[index];
}

- (id)descriptionWithLocale:(id)locale indent:(NSUInteger)level
{
    NSString *indentation = [@"" stringByPaddingToLength:level withString:@" " startingAtIndex:0];

    NSMutableString *output = [NSMutableString stringWithCapacity:4096];
    [output appendString:indentation];
    [output appendString:@"(\n"];
    for (NSString *line in _descriptions)
        [output appendFormat:@"%@\t%@\n",indentation,line];
    [output appendString:indentation];
    [output appendString:@")"];
    return [NSString stringWithString:output];
}


- (void) loadSymbols:(NSDictionary *)symbols // Replace all <redacted> strings with actual symbol names
{
    for (int i=0;i<[_descriptions count];i++)
        for (NSString *hexAddress in [symbols allKeys])
            _descriptions[i] = [[_descriptions[i] stringByReplacingOccurrencesOfString:[NSString stringWithFormat:@"%@",hexAddress] withString:[NSString stringWithFormat:@"%@ %@",hexAddress,symbols[hexAddress]]] stringByReplacingOccurrencesOfString:@"<redacted>" withString:@""];
}

- (void)dealloc
{
    [_descriptions release];
    [super dealloc];
}

@end