/* -*- C++ -*- */
// $Id$

// ============================================================================
//
// = LIBRARY
//    ace
//
// = FILENAME
//    Read_Buffer.h
//
// = AUTHOR
//    Doug Schmidt and Seth Widoff
//
// ============================================================================

#if !defined (ACE_READ_BUFFER_H)
#define ACE_READ_BUFFER_H

#include "ace/ACE.h"
#include "ace/Malloc.h"

class ACE_Export ACE_Read_Buffer
{
  // = TITLE
  //     Efficiently reads an artibrarily large buffer from an input
  //     stream up to and including a termination character.  Also
  //     performs search/replace on single occurrences a character in
  //     the buffer using the principles of Integrated Layer
  //     Processing.
  //
  // = DESCRIPTION
  //     This implementation is optimized to do a single dynamic
  //     allocation and make only one copy of the data.  It uses
  //     recursion and the run-time stack to accomplish this
  //     efficiently.
public:
  // = Initialization and termination methods.
  ACE_Read_Buffer (FILE *fp, int close_on_delete = 0, ACE_Allocator * = 0);
  // Read from a FILE *.

  ACE_Read_Buffer (ACE_HANDLE handle, int close_on_delete = 0, ACE_Allocator * = 0);
  // Read from an open HANDLE.

  ~ACE_Read_Buffer (void);
  // Closes the FILE *.

  // Returns a dynamically allocated pointer to n+1 bytes of data from
  // the input stream up to (and including) the <terminator>.  If
  // <search> is >= 0 then all occurrences of the <search> value are
  // substituted with the <replace> value.  The last of the n+1 bytes
  // of data is a 0, so that if data is test, strlen () can be used on
  // it.
  char *read (int terminator = EOF,
              int search = '\n',
              int replace = '\0');

  size_t replaced (void) const;
  // Returns the number of characters replaced during a <read>.

  size_t size (void) const;
  // Returns the size of the allocated buffer obtained during a <read>,
  // not including the null terminator.

  void dump (void) const;
  // Dump the state of the object.

private:
  char *rec_read (int term, int search, int replace);
  // Recursive helper method that does the work...

  size_t size_;
  // The total number of characters in the buffer.

  size_t occurrences_;
  // The total number of characters replaced.

  FILE *stream_;
  // The stream we are reading from.

  int close_on_delete_;
  // Keeps track of whether we should close the FILE in the
  // destructor.

  ACE_Allocator *allocator_;
  // Pointer to the allocator.

  // = Disallow copying and assignment...
  void operator= (const ACE_Read_Buffer &);
  ACE_Read_Buffer (const ACE_Read_Buffer &);
};

#if defined (__ACE_INLINE__)
# include "ace/Read_Buffer.i"
#endif /* __ACE_INLINE__ */

#endif /* ACE_READ_BUFFER_H */