Add an abstract IOStream class

6 files changed, 235 insertions, 17 deletions

diff --git a/taglib/mpeg/mpegfile.cpp b/taglib/mpeg/mpegfile.cpp
index 3b3513ae..9786c99a 100644
--- a/taglib/mpeg/mpegfile.cpp
+++ b/taglib/mpeg/mpegfile.cpp
@@ -113,6 +113,16 @@ MPEG::File::File(FileName file, ID3v2::FrameFactory *frameFactory,
     read(readProperties, propertiesStyle);
 }
 
+MPEG::File::File(IOStream *stream, ID3v2::FrameFactory *frameFactory,
+                 bool readProperties, Properties::ReadStyle propertiesStyle) :
+  TagLib::File(stream)
+{
+  d = new FilePrivate(frameFactory);
+
+  if(isOpen())
+    read(readProperties, propertiesStyle);
+}
+
 MPEG::File::~File()
 {
   delete d;
diff --git a/taglib/mpeg/mpegfile.h b/taglib/mpeg/mpegfile.h
index 7b41328a..cff5469d 100644
--- a/taglib/mpeg/mpegfile.h
+++ b/taglib/mpeg/mpegfile.h
@@ -85,13 +85,26 @@ namespace TagLib {
        * file's audio properties will also be read using \a propertiesStyle.  If
        * false, \a propertiesStyle is ignored.  The frames will be created using
        * \a frameFactory.
+       *
+       * \deprecated This constructor will be dropped in favor of the one below
+       * in a future version.
        */
-      // BIC: merge with the above constructor
       File(FileName file, ID3v2::FrameFactory *frameFactory,
            bool readProperties = true,
            Properties::ReadStyle propertiesStyle = Properties::Average);
 
       /*!
+       * Contructs an MPEG file from \a stream.  If \a readProperties is true the
+       * file's audio properties will also be read using \a propertiesStyle.  If
+       * false, \a propertiesStyle is ignored.  The frames will be created using
+       * \a frameFactory.
+       */
+      // BIC: merge with the above constructor
+      File(IOStream *stream, ID3v2::FrameFactory *frameFactory,
+           bool readProperties = true,
+           Properties::ReadStyle propertiesStyle = Properties::Average);
+
+      /*!
        * Destroys this instance of the File.
        */
       virtual ~File();
diff --git a/taglib/toolkit/tfile.cpp b/taglib/toolkit/tfile.cpp
index 946d7ea2..63c28e5a 100644
--- a/taglib/toolkit/tfile.cpp
+++ b/taglib/toolkit/tfile.cpp
@@ -71,6 +71,7 @@ public:
   FilePrivate(FileName fileName);
 
   FILE *file;
+  IOStream *stream;
 
   FileNameHandle name;
 
@@ -129,6 +130,12 @@ File::File(FileName file)
   d = new FilePrivate(file);
 }
 
+File::File(IOStream *stream)
+{
+  d = new FilePrivate(""); // TODO
+  d->stream = stream;
+}
+
 File::~File()
 {
   if(d->file)
diff --git a/taglib/toolkit/tfile.h b/taglib/toolkit/tfile.h
index da322809..ee6f0488 100644
--- a/taglib/toolkit/tfile.h
+++ b/taglib/toolkit/tfile.h
@@ -29,6 +29,7 @@
 #include "taglib_export.h"
 #include "taglib.h"
 #include "tbytevector.h"
+#include "tiostream.h"
 
 namespace TagLib {
 
@@ -36,22 +37,6 @@ namespace TagLib {
   class Tag;
   class AudioProperties;
 
-#ifdef _WIN32
-  class TAGLIB_EXPORT FileName
-  {
-  public:
-    FileName(const wchar_t *name) : m_wname(name) {}
-    FileName(const char *name) : m_name(name) {}
-    operator const wchar_t *() const { return m_wname.c_str(); }
-    operator const char *() const { return m_name.c_str(); }
-  private:
-    std::string m_name;
-    std::wstring m_wname;
-  };
-#else
-  typedef const char *FileName;
-#endif
-
   //! A file class with some useful methods for tag manipulation
 
   /*!
@@ -241,6 +226,14 @@ namespace TagLib {
     File(FileName file);
 
     /*!
+     * Construct a File object and use the \a stream instance.
+     *
+     * \note Constructor is protected since this class should only be
+     * instantiated through subclasses.
+     */
+    File(IOStream *stream);
+
+    /*!
      * Marks the file as valid or invalid.
      *
      * \see isValid()
diff --git a/taglib/toolkit/tiostream.cpp b/taglib/toolkit/tiostream.cpp
new file mode 100644
index 00000000..12c4b6fe
--- /dev/null
+++ b/taglib/toolkit/tiostream.cpp
@@ -0,0 +1,37 @@
+/***************************************************************************
+    copyright            : (C) 2011 by Lukas Lalinsky
+    email                : lalinsky@gmail.com
+ ***************************************************************************/
+
+/***************************************************************************
+ *   This library is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU Lesser General Public License version   *
+ *   2.1 as published by the Free Software Foundation.                     *
+ *                                                                         *
+ *   This library is distributed in the hope that it will be useful, but   *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
+ *   Lesser General Public License for more details.                       *
+ *                                                                         *
+ *   You should have received a copy of the GNU Lesser General Public      *
+ *   License along with this library; if not, write to the Free Software   *
+ *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA         *
+ *   02110-1301  USA                                                       *
+ *                                                                         *
+ *   Alternatively, this file is available under the Mozilla Public        *
+ *   License Version 1.1.  You may obtain a copy of the License at         *
+ *   http://www.mozilla.org/MPL/                                           *
+ ***************************************************************************/
+
+#include "tiostream.h"
+
+using namespace TagLib;
+
+////////////////////////////////////////////////////////////////////////////////
+// public members
+////////////////////////////////////////////////////////////////////////////////
+
+IOStream::~IOStream()
+{
+  delete d;
+}
diff --git a/taglib/toolkit/tiostream.h b/taglib/toolkit/tiostream.h
new file mode 100644
index 00000000..fee02e8f
--- /dev/null
+++ b/taglib/toolkit/tiostream.h
@@ -0,0 +1,158 @@
+/***************************************************************************
+    copyright            : (C) 2011 by Lukas Lalinsky
+    email                : lalinsky@gmail.com
+ ***************************************************************************/
+
+/***************************************************************************
+ *   This library is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU Lesser General Public License version   *
+ *   2.1 as published by the Free Software Foundation.                     *
+ *                                                                         *
+ *   This library is distributed in the hope that it will be useful, but   *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
+ *   Lesser General Public License for more details.                       *
+ *                                                                         *
+ *   You should have received a copy of the GNU Lesser General Public      *
+ *   License along with this library; if not, write to the Free Software   *
+ *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA         *
+ *   02110-1301  USA                                                       *
+ *                                                                         *
+ *   Alternatively, this file is available under the Mozilla Public        *
+ *   License Version 1.1.  You may obtain a copy of the License at         *
+ *   http://www.mozilla.org/MPL/                                           *
+ ***************************************************************************/
+
+#ifndef TAGLIB_IOSTREAM_H
+#define TAGLIB_IOSTREAM_H
+
+#include "taglib_export.h"
+#include "taglib.h"
+#include "tbytevector.h"
+
+namespace TagLib {
+
+#ifdef _WIN32
+  class TAGLIB_EXPORT FileName
+  {
+  public:
+    FileName(const wchar_t *name) : m_wname(name) {}
+    FileName(const char *name) : m_name(name) {}
+    operator const wchar_t *() const { return m_wname.c_str(); }
+    operator const char *() const { return m_name.c_str(); }
+  private:
+    std::string m_name;
+    std::wstring m_wname;
+  };
+#else
+  typedef const char *FileName;
+#endif
+
+  //! An abstract class that provides operations on a sequence of bytes
+
+  class TAGLIB_EXPORT IOStream
+  {
+  public:
+    /*!
+     * Position in the file used for seeking.
+     */
+    enum Position {
+      //! Seek from the beginning of the file.
+      Beginning,
+      //! Seek from the current position in the file.
+      Current,
+      //! Seek from the end of the file.
+      End
+    };
+
+    /*!
+     * Destroys this IOStream instance.
+     */
+    virtual ~IOStream();
+
+    /*!
+     * Returns the stream name in the local file system encoding.
+     */
+    virtual FileName name() const = 0;
+
+    /*!
+     * Reads a block of size \a length at the current get pointer.
+     */
+    virtual ByteVector readBlock(ulong length) = 0;
+
+    /*!
+     * Attempts to write the block \a data at the current get pointer.  If the
+     * file is currently only opened read only -- i.e. readOnly() returns true --
+     * this attempts to reopen the file in read/write mode.
+     *
+     * \note This should be used instead of using the streaming output operator
+     * for a ByteVector.  And even this function is significantly slower than
+     * doing output with a char[].
+     */
+    virtual void writeBlock(const ByteVector &data) = 0;
+
+    /*!
+     * Insert \a data at position \a start in the file overwriting \a replace
+     * bytes of the original content.
+     *
+     * \note This method is slow since it requires rewriting all of the file
+     * after the insertion point.
+     */
+    virtual void insert(const ByteVector &data, ulong start = 0, ulong replace = 0) = 0;
+
+    /*!
+     * Removes a block of the file starting a \a start and continuing for
+     * \a length bytes.
+     *
+     * \note This method is slow since it involves rewriting all of the file
+     * after the removed portion.
+     */
+    virtual void removeBlock(ulong start = 0, ulong length = 0) = 0;
+
+    /*!
+     * Returns true if the file is read only (or if the file can not be opened).
+     */
+    virtual bool readOnly() const = 0;
+
+    /*!
+     * Since the file can currently only be opened as an argument to the
+     * constructor (sort-of by design), this returns if that open succeeded.
+     */
+    virtual bool isOpen() const = 0;
+
+    /*!
+     * Returns true if the file is open and readble.
+     */
+    virtual bool isValid() const = 0;
+
+    /*!
+     * Move the I/O pointer to \a offset in the stream from position \a p.  This
+     * defaults to seeking from the beginning of the stream.
+     *
+     * \see Position
+     */
+    virtual void seek(long offset, Position p = Beginning) = 0;
+
+    /*!
+     * Reset the end-of-stream and error flags on the stream.
+     */
+    virtual void clear() = 0;
+
+    /*!
+     * Returns the current offset within the stream.
+     */
+    virtual long tell() const = 0;
+
+    /*!
+     * Returns the length of the stream.
+     */
+    virtual long length() = 0;
+
+  private:
+    IOStream(const IOStream &);
+    IOStream &operator=(const IOStream &);
+  };
+
+}
+
+#endif