如何判断iOS设备硬件型号

+ (NSString*)getMachine{
    size_t size;
    sysctlbyname("hw.machine", NULL, &size, NULL, 0);
    char *name = malloc(size);
    sysctlbyname("hw.machine", name, &size, NULL, 0);
    
    NSString *machine = [NSString stringWithCString:name encoding:NSUTF8StringEncoding];
    
    free(name);

    if( [machine isEqualToString:@"i386"] || [machine isEqualToString:@"x86_64"] ) machine = @"ios_Simulator";
    else if( [machine isEqualToString:@"iPhone1,1"] ) machine = @"iPhone_1G";
    else if( [machine isEqualToString:@"iPhone1,2"] ) machine = @"iPhone_3G";
    else if( [machine isEqualToString:@"iPhone2,1"] ) machine = @"iPhone_3GS";
    else if( [machine isEqualToString:@"iPhone3,1"] ) machine = @"iPhone_4";
    else if( [machine isEqualToString:@"iPod1,1"] ) machine = @"iPod_Touch_1G";
    else if( [machine isEqualToString:@"iPod2,1"] ) machine = @"iPod_Touch_2G";
    else if( [machine isEqualToString:@"iPod3,1"] ) machine = @"iPod_Touch_3G";
    else if( [machine isEqualToString:@"iPod4,1"] ) machine = @"iPod_Touch_4G";
    else if( [machine isEqualToString:@"iPad1,1"] ) machine = @"iPad_1";
    else if( [machine isEqualToString:@"iPad2,1"] ) machine = @"iPad_2";
    
    return machine;
}