如何在ios中使用ASL获取控制台日志？

Question

我想使用ASL获取控制台日志。我已经编写了下面的代码，并且我在iPhone模拟器中获得了所有控制台日志，但是当我使用iPhone 4.1和iPad时，我从控制台开始就没有充分的手段。我尝试了很多。

- (NSMutableArray *)getAppLogByApp:(NSString *)appName 
{ 
    NSMutableArray  *lObjAppLogsPtr = (NSMutableArray *)nil; 
    LogInfo   *lObjLogInfoPtr = (LogInfo *)nil; 

    aslmsg q, m; 
    int i; 
    const char *key, *val, *lAppName; 
    NSDateFormatter *lObjDateFormatter = [[NSDateFormatter alloc] init]; 
    [lObjDateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"]; 


    q = asl_new(ASL_TYPE_QUERY); 

    //also set the log level to fetch if is set to the global variable m_cObjLogMessageLevel 
    const char* lObjASLLogLevel = [[NSString stringWithFormat:@"%d", m_cLogMessageLevel] UTF8String]; 
    asl_set_query(q, ASL_KEY_LEVEL, lObjASLLogLevel, ASL_QUERY_OP_LESS_EQUAL | ASL_QUERY_OP_NUMERIC); 
    //asl_set_query(q, ASL_KEY_LEVEL, lObjASLLogLevel, ASL_QUERY_OP_EQUAL | ASL_QUERY_OP_NUMERIC); 
    //if appName passed to it then fetch the logs for this application only 
    if ((NSString *)nil != appName && 0 < appName.length) 
    { 
     lAppName = [appName UTF8String]; 
     asl_set_query(q, ASL_KEY_SENDER, lAppName, ASL_QUERY_OP_EQUAL); 
    } 

    aslresponse r = asl_search(NULL, q); 

    while (NULL != (m = aslresponse_next(r))) 
    { 
     if ((NSMutableArray *)nil == lObjAppLogsPtr) 
     { 
      lObjAppLogsPtr = [[NSMutableArray alloc] init]; 
     } 

     for (i = 0; (NULL != (key = asl_key(m, i))); i++) 
     { 
      NSString *keyString = [NSString stringWithUTF8String:(char *)key]; 

      val = asl_get(m, key); 

      NSString *lObjValString = nil; 
      if (nil != val) 
      { 
       lObjValString = [NSString stringWithUTF8String:val]; 
      } 
      else 
      { 
       //NSLog(@"Val in nil"); 
       lObjValString = @""; 
      } 

      if ((LogInfo *)nil == lObjLogInfoPtr) 
      { 
       lObjLogInfoPtr = [[LogInfo alloc] init]; 
      } 


      if(YES == [keyString isEqualToString:@"Level"]) 
      { 
       lObjLogInfoPtr.m_cObjLevel = lObjValString; 
      } 
      else if(YES == [keyString isEqualToString:@"Time"]) 
      { 
       //convert the time to YYYY-MM-DD HH:MM:SS format 
       time_t time = strtol(val, NULL, 0); 

       NSDate *lObjDatePtr = [[NSDate dateWithTimeIntervalSince1970:time] copy]; 
       NSString *lObjDateStringPtr = [lObjDateFormatter stringFromDate:lObjDatePtr]; 
       lObjLogInfoPtr.m_cObjTime = lObjDateStringPtr; 
      } 
      else if(YES == [keyString isEqualToString:@"Sender"]) 
      { 
       lObjLogInfoPtr.m_cObjSender = lObjValString; 
      } 
      else if(YES == [keyString isEqualToString:@"Message"]) 
      { 
       lObjLogInfoPtr.m_cObjMessage = lObjValString; 
      } 
     } 

     //Add the loginfo array 
     [lObjAppLogsPtr addObject:lObjLogInfoPtr]; 
     //Release the loginfo and set it to nil for further use 
     [lObjLogInfoPtr release]; 
     lObjLogInfoPtr = (LogInfo *)nil; 
    } 

    if (NULL != r) 
    { 
     aslresponse_free(r); 
    } 

    //free the als msg object 
    asl_free(q); 
    [lObjDateFormatter release]; 


    return lObjAppLogsPtr; 
} 

这里LogIngo是NSObject一个子类。 请帮助我。自一周以来我一直在尝试。

Answer 1

在Mac上（因此在iOS模拟器中）的行为是不同的;在Mac上，默认情况下，进程可以读取其他进程创建的日志条目。在iOS设备上，ASL将只有返回由进程生成的日志条目，并且仅当您明确将ASL_KEY_READ_UID设置为“-1”时。

另外，日志在设备上被修剪得相当积极，并且可能只包含应用程序当前运行所做的条目。 （如果您想保留日志条目并且使用Swift，则可能需要查看更强大的日志记录程序包，例如CleanroomLogger。）

如果您使用的是Swift，源项目名为CleanroomASL，它提供了用于读写Apple系统日志条目的类型安全API。使用CleanroomASL，搜索翔升日志条目看起来像：

let client = ASLClient() 
let query = ASLQueryObject() 

client.search(query) { record in 
    if let record = record { 
     // we've gotten a log entry for the search. 
     // 'record' is of type ASLQueryObject.ResultRecord 
    } 
    else { 
     // there are no more log entries to process 
    } 
    // return true while we still want to get results 
    // or return false when we don't want to process more 
    return true 
} 

您可以通过设置额外的查询键约束自己的搜索查询：

query.setQueryKey(.Message, value: nil, operation: .KeyExists, modifiers: .None) 
query.setQueryKey(.Time, value: Int(NSDate().timeIntervalSince1970 - (60 * 60)), operation: .GreaterThanOrEqualTo, modifiers: .None) 

上面的代码将返回记录的最后都ASL日志条目5分钟也具有.Message属性的值。