解析FTP LIST命令返回的目录列表

有个程序要分析FTP服务器返回的目录列表，本来以为比较简单，也在网上查了几个帖子，可都是一知半解的。于是下载了Filezilla的源代码，她的源文件
directorylistingparser.h
directorylistingparser.cpp
就是解析目录列表的，有同样需求的不妨看一看，还是挺费事的，不同平台要都要特殊处理。我把头文件贴出来：

#ifndef __DIRECTORYLISTINGPARSER_H__
#define __DIRECTORYLISTINGPARSER_H__

/* This class is responsible for parsing the directory listings returned by
* the server.
* Unfortunatly, RFC959 did not specify the format of directory listings, so
* each server uses its own format. In addition to that, in most cases the
* listings were not designed to be machine-parsable, they were meant to be
* human readable by users of that particular server.
* By far the most common format is the one returned by the Unix "ls -l"
* command. However, legacy systems are still in place, especially in big
* companies. These often use very exotic listing styles.
* Another problem are localized listings containing date strings. In some
* cases these listings are ambiguous and cannot be distinguished.
* Example for an ambiguous date: 04-05-06. All of the 6 permutations for
* the location of year, month and day are valid dates.
* Some servers send multiline listings where a single entry can span two
* lines, this has to be detected as well, as far as possible.
*
* Some servers send MVS style listings which can consist of just the
* filename without any additional data. In order to prevent problems, this
* format is only parsed if the server is in fact recognizes as MVS server.
*
* Please see tests/dirparsertest.cpp for a list of supported formats and the
* expected parser result.
*
* If adding data to the parser, it first decomposes the raw data into lines,
* which then are processed further. Each line gets consecutively tested for
* different formats, starting with the most common Unix style format.
* Lines not containing a recognized format (e.g. a part of a multiline
* entry) are rememberd and if the next line cannot be parsed either, they
* get concatenated to be parsed again (and discarded if not recognized).
*/

class CLine;
class CToken;
class CControlSocket;
class CDirectoryListingParser
{
public:
  CDirectoryListingParser(CControlSocket* pControlSocket, const CServer& server);
  ~CDirectoryListingParser();

  CDirectoryListing Parse( const CServerPath &path);

   void AddData( char *pData, int len);
   void AddLine( const wxChar* pLine);

   void Reset();

   void SetTimezoneOffset( const wxTimeSpan& span) { m_timezoneOffset = span; }

   void SetServer( const CServer& server) { m_server = server; };

protected:
  CLine *GetLine( bool breakAtEnd = false);

   void ParseData( bool partial);

   bool ParseLine(CLine *pLine, const enum ServerType serverType, bool concatenated);

   bool ParseAsUnix(CLine *pLine, CDirentry &entry, bool expect_date);
   bool ParseAsDos(CLine *pLine, CDirentry &entry);
   bool ParseAsEplf(CLine *pLine, CDirentry &entry);
   bool ParseAsVms(CLine *pLine, CDirentry &entry);
   bool ParseAsIbm(CLine *pLine, CDirentry &entry);
   bool ParseOther(CLine *pLine, CDirentry &entry);
   bool ParseAsWfFtp(CLine *pLine, CDirentry &entry);
   bool ParseAsIBM_MVS(CLine *pLine, CDirentry &entry);
   bool ParseAsIBM_MVS_PDS(CLine *pLine, CDirentry &entry);
   bool ParseAsIBM_MVS_PDS2(CLine *pLine, CDirentry &entry);
   bool ParseAsIBM_MVS_Migrated(CLine *pLine, CDirentry &entry);
   bool ParseAsMlsd(CLine *pLine, CDirentry &entry);
   bool ParseAsOS9(CLine *pLine, CDirentry &entry);
  
   // Only call this if servertype set to ZVM since it conflicts
   // with other formats.
   bool ParseAsZVM(CLine *pLine, CDirentry &entry);

   // Only call this if servertype set to HPNONSTOP since it conflicts
   // with other formats.
   bool ParseAsHPNonstop(CLine *pLine, CDirentry &entry);

   // Date / time parsers
   bool ParseUnixDateTime(CLine *pLine, int &index, CDirentry &entry);
   bool ParseShortDate(CToken &token, CDirentry &entry, bool saneFieldOrder = false);
   bool ParseTime(CToken &token, CDirentry &entry);

   // Parse file sizes given like this: 123.4M
   bool ParseComplexFileSize(CToken& token, wxLongLong& size, int blocksize = -1);

   bool GetMonthFromName( const wxString& name, int &month);

  CControlSocket* m_pControlSocket;

   static std::map<wxString, int> m_MonthNamesMap;
  
   struct t_list
  {
     char *p;
     int len;
  };
   int m_currentOffset;

  std::list<t_list> m_DataList;
  std::list<CDirentry> m_entryList;

  CLine *m_prevLine;

  CServer m_server;

   bool m_fileListOnly;
  std::list<wxString> m_fileList;
  
   bool m_maybeMultilineVms;

  wxTimeSpan m_timezoneOffset;
};

#endif