ACE/ACEXML/common/FileCharStream.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file    FileCharStream.h
   6  *
   7  *  @author Nanbor Wang <nanbor@cs.wustl.edu>
   8  */
   9 //=============================================================================
  10
  11 #ifndef _ACEXML_FILECHARSTREAM_H_
  12 #define _ACEXML_FILECHARSTREAM_H_
  13
  14 #include /**/ "ace/pre.h"
  15 #include "ACEXML/common/ACEXML_Export.h"
  16
  17 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  18 #pragma once
  19 #endif /* ACE_LACKS_PRAGMA_ONCE */
  20
  21 #include "ACEXML/common/CharStream.h"
  22 #include "ACEXML/common/Encoding.h"
  23
  24 /**
  25  * @class ACEXML_FileCharStream
  26  *
  27  * An implementation of ACEXML_CharStream for reading input from a file.
  28  */
  29 class ACEXML_Export ACEXML_FileCharStream : public ACEXML_CharStream
  30 {
  31 public:
  32   /// Default constructor.
  33   ACEXML_FileCharStream ();
  34
  35   /// Destructor
  36   virtual ~ACEXML_FileCharStream ();
  37
  38   /// Open a file.
  39   int open (const ACEXML_Char *name);
  40
  41   /**
  42    * Accept an already opened file. The stream does not
  43    * assume ownership of open_file.
  44    */
  45   int use_stream (FILE* open_file, const ACEXML_Char *name);
  46
  47   /**
  48    * Returns the available ACEXML_Char in the buffer.  -1
  49    * if the object is not initialized properly.
  50    */
  51   virtual int available ();
  52
  53   /**
  54    * Close this stream and release all resources used by it.
  55    */
  56   virtual int close ();
  57
  58   /**
  59    * Read the next ACEXML_Char.  Return -1 if we are not able to
  60    * return an ACEXML_Char, 0 if succees.
  61    */
  62   virtual int get (ACEXML_Char& ch);
  63
  64   /**
  65    * Read the next batch of ACEXML_Char strings
  66    */
  67   virtual int read (ACEXML_Char *str,
  68                     size_t len);
  69
  70   /**
  71    *  Determine the encoding of the file.
  72    */
  73   virtual int determine_encoding ();
  74
  75
  76   /**
  77    * Peek the next ACEXML_Char in the CharStream.  Return the
  78    * character if success, -1 if EOF is reached.
  79    */
  80   virtual int peek ();
  81
  82   /**
  83    *  Resets the file pointer to the beginning of the stream.
  84    */
  85   virtual void rewind ();
  86
  87   /*
  88    * Get the character encoding for the file.
  89    */
  90   virtual const ACEXML_Char *getEncoding ();
  91
  92   /*
  93    * Get the systemId for the underlying CharStream
  94    */
  95   virtual const ACEXML_Char* getSystemId ();
  96
  97 private:
  98   /** Read the next character as a normal character. Return -1 if EOF is
  99    *  reached, else return 0.
 100    */
 101   int getchar_i (char& ch);
 102
 103 #if defined (ACE_USES_WCHAR)
 104   /**
 105    *  Read the next character from the stream taking into account the
 106    *  encoding of the file.
 107    */
 108   int get_i (ACEXML_Char& ch);
 109
 110   /**
 111    *  Read the next character from the stream taking into account the
 112    *  encoding of the file. Subsequent call to get() returns this
 113    *  character.
 114    */
 115   int peek_i ();
 116
 117 #endif /* ACE_USES_WCHAR */
 118
 119   /// internal accept an already opened file.
 120   int use_stream_i (FILE* open_file, const ACEXML_Char *name);
 121
 122   ACEXML_Char*  filename_;
 123   ACEXML_Char*  encoding_;
 124   ACE_OFF_T     size_;
 125   FILE*         infile_;
 126   bool          close_infile_;
 127   // This is needed to ensure that we can implement a peek operation on a
 128   // UTF-16 encoded file. It is a bit hackish, but there is no other way of
 129   // implementing a peek() as the standard I/O FILE* guarantees only one
 130   // pushback.
 131   ACEXML_Char   peek_;
 132 };
 133
 134
 135 #include /**/ "ace/post.h"
 136
 137 #endif /* _ACEXML_FILECHARSTREAM_H_ */