diff base/MatrixFileCache.cpp @ 87:7de62a884810

* Start factoring out the spectrogram's FFT cache into a separate set of
  classes that will permit a choice of disk or memory cache strategies

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/base/MatrixFileCache.cpp	Tue May 02 12:27:41 2006 +0000
@@ -0,0 +1,266 @@
+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+
+/*
+    Sonic Visualiser
+    An audio file viewer and annotation editor.
+    Centre for Digital Music, Queen Mary, University of London.
+    This file copyright 2006 Chris Cannam.
+    
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License as
+    published by the Free Software Foundation; either version 2 of the
+    License, or (at your option) any later version.  See the file
+    COPYING included with this distribution for more information.
+*/
+
+#include "MatrixFileCache.h"
+#include "base/TempDirectory.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <iostream>
+
+#include <cstdio>
+
+#include <QFileInfo>
+#include <QDir>
+
+MatrixFileCache::MatrixFileCache(QString fileBase, Mode mode) :
+    m_fd(-1),
+    m_off(-1),
+    m_mode(mode),
+    m_width(0),
+    m_height(0),
+    m_rx(0),
+    m_rw(0),
+    m_range(0),
+    m_headerSize(2 * sizeof(size_t))
+{
+    QDir tempDir(TempDirectory::instance()->getPath());
+    QString fileName(tempDir.filePath(QString("%1.mfc").arg(fileBase)));
+    bool newFile = !QFileInfo(fileName).exists();
+
+    if (newFile && mode == ReadOnly) {
+        std::cerr << "ERROR: MatrixFileCache::MatrixFileCache: Read-only mode "
+                  << "specified, but cache file does not exist" << std::endl;
+        return;
+    }
+
+    int flags = 0;
+    mode_t fmode = S_IRUSR | S_IWUSR;
+
+    if (mode == ReadWrite) {
+        flags = O_RDWR | O_CREAT;
+    } else {
+        flags = O_RDONLY;
+    }
+
+    if ((m_fd = ::open(fileName.toLocal8Bit(), flags, mode)) < 0) {
+        ::perror("Open failed");
+        std::cerr << "ERROR: MatrixFileCache::MatrixFileCache: "
+                  << "Failed to open cache file \""
+                  << fileName.toStdString() << "\"";
+        if (mode == ReadWrite) std::cerr << " for writing";
+        std::cerr << std::endl;
+    }
+
+    if (newFile) {
+        resize(0, 0); // write header
+    } else {
+        size_t header[2];
+        if (::read(m_fd, header, 2 * sizeof(size_t))) {
+            perror("Read failed");
+            std::cerr << "ERROR: MatrixFileCache::MatrixFileCache: "
+                      << "Failed to read header" << std::endl;
+            return;
+        }
+        m_width = header[0];
+        m_height = header[1];
+        seekTo(0, 0);
+    }
+
+    std::cerr << "MatrixFileCache::MatrixFileCache: Done, size is " << m_width << "x" << m_height << std::endl;
+
+}
+
+MatrixFileCache::~MatrixFileCache()
+{
+    if (m_fd >= 0) {
+        if (::close(m_fd) < 0) {
+            ::perror("MatrixFileCache::~MatrixFileCache: close failed");
+        }
+    }
+}
+
+size_t 
+MatrixFileCache::getWidth() const
+{
+    return m_width;
+}
+
+size_t
+MatrixFileCache::getHeight() const
+{
+    return m_height;
+}
+
+void
+MatrixFileCache::resize(size_t w, size_t h)
+{
+    if (m_mode != ReadWrite) {
+        std::cerr << "ERROR: MatrixFileCache::resize called on read-only cache"
+                  << std::endl;
+        return;
+    }
+
+    off_t off = m_headerSize + (w * h * sizeof(float));
+
+    if (w * h > m_width * m_height) {
+
+        if (::lseek(m_fd, off - sizeof(float), SEEK_SET) == (off_t)-1) {
+            ::perror("Seek failed");
+            std::cerr << "ERROR: MatrixFileCache::resize(" << w << ", "
+                      << h << "): seek failed, cannot resize" << std::endl;
+            return;
+        }
+
+        // guess this requires efficient support for sparse files
+        
+        float f(0);
+        if (::write(m_fd, &f, sizeof(float)) != sizeof(float)) {
+            ::perror("WARNING: MatrixFileCache::resize: write failed");
+        }
+
+    } else {
+        
+        if (::ftruncate(m_fd, off) < 0) {
+            ::perror("MatrixFileCache::resize: ftruncate failed");
+        }
+    }
+
+    m_width = 0;
+    m_height = 0;
+    m_off = 0;
+
+    if (::lseek(m_fd, 0, SEEK_SET) == (off_t)-1) {
+        ::perror("ERROR: MatrixFileCache::resize: Seek to write header failed");
+        return;
+    }
+
+    size_t header[2];
+    header[0] = w;
+    header[1] = h;
+    if (::write(m_fd, header, 2 * sizeof(size_t)) != 2 * sizeof(size_t)) {
+        ::perror("ERROR: MatrixFileCache::resize: Failed to write header");
+        return;
+    }
+
+    m_width = w;
+    m_height = h;
+
+    seekTo(0, 0);
+}
+
+void
+MatrixFileCache::reset()
+{
+    if (m_mode != ReadWrite) {
+        std::cerr << "ERROR: MatrixFileCache::reset called on read-only cache"
+                  << std::endl;
+        return;
+    }
+    
+    //...
+}
+
+void
+MatrixFileCache::setRangeOfInterest(size_t x, size_t width)
+{
+}
+
+float
+MatrixFileCache::getValueAt(size_t x, size_t y) const
+{
+    if (m_rw > 0 && x >= m_rx && x < m_rx + m_rw) {
+        return m_range[x - m_rx][y];
+    }
+
+    if (!seekTo(x, y)) return 0.f;
+    float value;
+    if (::read(m_fd, &value, sizeof(float)) != sizeof(float)) {
+        ::perror("MatrixFileCache::getValueAt: read failed");
+        return 0.f;
+    }
+    return value;
+}
+
+void
+MatrixFileCache::getColumnAt(size_t x, float *values) const
+{
+    if (m_rw > 0 && x >= m_rx && x < m_rx + m_rw) {
+        for (size_t y = 0; y < m_height; ++y) {
+            values[y] = m_range[x - m_rx][y];
+        }
+    }
+
+    if (!seekTo(x, 0)) return;
+    if (::read(m_fd, values, m_height * sizeof(float)) != m_height * sizeof(float)) {
+        ::perror("MatrixFileCache::getColumnAt: read failed");
+    }
+    return;
+}
+
+void
+MatrixFileCache::setValueAt(size_t x, size_t y, float value)
+{
+    if (m_mode != ReadWrite) {
+        std::cerr << "ERROR: MatrixFileCache::setValueAt called on read-only cache"
+                  << std::endl;
+        return;
+    }
+
+    if (!seekTo(x, y)) return;
+    if (::write(m_fd, &value, sizeof(float)) != sizeof(float)) {
+        ::perror("WARNING: MatrixFileCache::setValueAt: write failed");
+    }
+
+    //... update range as appropriate
+}
+
+void
+MatrixFileCache::setColumnAt(size_t x, float *values)
+{
+    if (m_mode != ReadWrite) {
+        std::cerr << "ERROR: MatrixFileCache::setColumnAt called on read-only cache"
+                  << std::endl;
+        return;
+    }
+
+    if (!seekTo(x, 0)) return;
+    if (::write(m_fd, values, m_height * sizeof(float)) != m_height * sizeof(float)) {
+        ::perror("WARNING: MatrixFileCache::setColumnAt: write failed");
+    }
+
+    //... update range as appropriate
+}
+
+bool
+MatrixFileCache::seekTo(size_t x, size_t y) const
+{
+    off_t off = m_headerSize + (x * m_height + y) * sizeof(float);
+    if (off == m_off) return true;
+
+    if (::lseek(m_fd, off, SEEK_SET) == (off_t)-1) {
+        ::perror("Seek failed");
+        std::cerr << "ERROR: MatrixFileCache::seekTo(" << x << ", " << y
+                  << ") failed" << std::endl;
+        return false;
+    }
+
+    m_off = off;
+    return true;
+}
+