[SCM] exiv2 packaging branch, master, updated. debian/0.25-3.1-3734-gdcbc29a

[Maximiliano Curia]

Gitweb-URL: http://git.debian.org/?p=pkg-kde/kde-extras/exiv2.git;a=commitdiff;h=ebe5bb0

The following commit has been merged in the master branch:
commit ebe5bb0a278121a36ee66bdfb1c6ed02753b99c1
Author: Andreas Huggel <ahuggel at gmx.net>
Date:   Sun Jun 25 18:11:01 2006 +0000

    Added experimental mmap support to improve read performance for TIFF and PNG images, barely tested and only on Linux
---
 src/basicio.cpp   | 32 +++++++++++++++++++++++++++++++-
 src/basicio.hpp   | 30 ++++++++++++++++++++++++++++++
 src/pngimage.cpp  |  8 +-------
 src/tiffimage.cpp |  9 +--------
 4 files changed, 63 insertions(+), 16 deletions(-)

diff --git a/src/basicio.cpp b/src/basicio.cpp
index 045a194..6424048 100644
--- a/src/basicio.cpp
+++ b/src/basicio.cpp
@@ -48,6 +48,7 @@ EXIV2_RCSID("@(#) $Id$")
 #include <cstdlib>                      // for alloc(), realloc(), free()
 #include <sys/types.h>                  // for stat()
 #include <sys/stat.h>                   // for stat()
+#include <sys/mman.h>                   // for mmap() and munmap()
 #ifdef EXV_HAVE_PROCESS_H
 # include <process.h>
 #endif
@@ -64,15 +65,44 @@ EXIV2_RCSID("@(#) $Id$")
 namespace Exiv2 {
 
     FileIo::FileIo(const std::string& path)
-        : path_(path), fp_(0), opMode_(opSeek)
+        : path_(path), fp_(0), opMode_(opSeek), pMappedArea_(0), mappedLength_(0)
     {
     }
 
     FileIo::~FileIo()
     {
+        munmap();
         close();
     }
 
+
+// Todo: Experimental
+    void FileIo::munmap()
+    {
+        if (pMappedArea_ != 0) {
+            if (::munmap(pMappedArea_, mappedLength_) != 0) {
+                throw Error(2, path_, strError(), "munmap");
+            }
+        }
+        pMappedArea_ = 0;
+        mappedLength_ = 0;
+    }
+
+    const byte* FileIo::mmap()
+    {
+        assert(fp_ != 0);
+        munmap();
+        mappedLength_ = size();
+        void* rc = ::mmap(0, mappedLength_, PROT_READ, MAP_SHARED, fileno(fp_), 0);
+        if (MAP_FAILED == rc) {
+            throw Error(2, path_, strError(), "mmap");            
+        }
+        pMappedArea_ = static_cast<byte*>(rc);
+        return pMappedArea_;
+    }
+
+
+
     BasicIo::AutoPtr FileIo::temporary() const
     {
         BasicIo::AutoPtr basicIo;
diff --git a/src/basicio.hpp b/src/basicio.hpp
index 1726569..61fb2f6 100644
--- a/src/basicio.hpp
+++ b/src/basicio.hpp
@@ -172,6 +172,17 @@ namespace Exiv2 {
               Nonzero if failure;
          */
         virtual int seek(long offset, Position pos) = 0;
+        /*!
+          @brief Allow efficient direct access to the IO data by mapping it 
+                 into the process's address space.
+
+          Todo: This is currently only for read access.
+         */
+        virtual const byte* mmap() =0;
+        /*!
+          @brief Remove a mapping established with mmap().
+         */
+        virtual void  munmap() =0;
         //@}
 
         //! @name Accessors
@@ -393,6 +404,12 @@ namespace Exiv2 {
                  Nonzero if failure;
          */
         virtual int seek(long offset, Position pos);
+        /*!
+          @brief Map the file into the process's address space. The file must
+                 be open before mmap() is called.
+         */
+        virtual const byte* mmap();
+        virtual void  munmap();
         //@}
 
         //! @name Accessors
@@ -446,6 +463,12 @@ namespace Exiv2 {
         FILE *fp_;
         OpMode opMode_;
 
+
+// Todo: Experimental
+        byte* pMappedArea_;
+        size_t mappedLength_;
+
+
         // METHODS
         /*!
           @brief Switch to a new access mode, reopening the file if needed.
@@ -589,6 +612,13 @@ namespace Exiv2 {
                  Nonzero if failure;
          */
         virtual int seek(long offset, Position pos);
+        /*!
+          @brief Allow direct access to the underlying data buffer. The buffer
+                 is not protected against write access except for the const
+                 specifier.
+         */
+        virtual const byte* mmap() { return data_; }
+        virtual void  munmap() {}
         //@}
 
         //! @name Accessors
diff --git a/src/pngimage.cpp b/src/pngimage.cpp
index 5174c98..a5d692e 100644
--- a/src/pngimage.cpp
+++ b/src/pngimage.cpp
@@ -126,20 +126,14 @@ namespace Exiv2 {
             throw Error(9, io_->path(), strError());
         }
         IoCloser closer(*io_);
-
         // Ensure that this is the correct image type
         if (!isThisType(*io_, false)) 
         {
             if (io_->error() || io_->eof()) throw Error(14);
             throw Error(3, "PNG");
         }
-
         clearMetadata();
-
-        DataBuf buf = io_->read(io_->size());
-        if (io_->error() || io_->eof()) throw Error(14);
-
-        PngChunk::decode(this, buf.pData_, buf.size_);
+        PngChunk::decode(this, io_->mmap(), io_->size());
 
     } // PngImage::readMetadata
 
diff --git a/src/tiffimage.cpp b/src/tiffimage.cpp
index a2444b3..7ff0eb3 100644
--- a/src/tiffimage.cpp
+++ b/src/tiffimage.cpp
@@ -126,14 +126,7 @@ namespace Exiv2 {
             throw Error(33);
         }
         clearMetadata();
-
-        // Read the image into a memory buffer
-        long len = io_->size();
-        DataBuf buf(len);
-        io_->read(buf.pData_, len);
-        if (io_->error() || io_->eof()) throw Error(14);
-
-        TiffParser::decode(this, buf.pData_, buf.size_,
+        TiffParser::decode(this, io_->mmap(), io_->size(),
                            TiffCreator::create, TiffDecoder::findDecoder);
 
     } // TiffImage::readMetadata

-- 
exiv2 packaging