diff data/fileio/FileSource.cpp @ 317:c324d410b096

* RemoteFile -> FileSource
  now it's used all over the place for local files as well.

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/data/fileio/FileSource.cpp	Thu Oct 18 16:20:26 2007 +0000
@@ -0,0 +1,718 @@
+/* -*- 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 2007 QMUL.
+    
+    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 "FileSource.h"
+#include "base/TempDirectory.h"
+#include "base/Exceptions.h"
+
+#include <QHttp>
+#include <QFtp>
+#include <QFileInfo>
+#include <QDir>
+#include <QApplication>
+#include <QProgressDialog>
+#include <QHttpResponseHeader>
+
+#include <iostream>
+
+int
+FileSource::m_count = 0;
+
+QMutex
+FileSource::m_fileCreationMutex;
+
+FileSource::RemoteRefCountMap
+FileSource::m_refCountMap;
+
+FileSource::RemoteLocalMap
+FileSource::m_remoteLocalMap;
+
+QMutex
+FileSource::m_mapMutex;
+
+FileSource::FileSource(QString fileOrUrl, bool showProgress) :
+    m_url(fileOrUrl),
+    m_ftp(0),
+    m_http(0),
+    m_localFile(0),
+    m_ok(false),
+    m_lastStatus(0),
+    m_remote(isRemote(fileOrUrl)),
+    m_done(false),
+    m_leaveLocalFile(false),
+    m_progressDialog(0),
+    m_progressShowTimer(this),
+    m_refCounted(false)
+{
+    std::cerr << "FileSource::FileSource(" << fileOrUrl.toStdString() << ")" << std::endl;
+
+    if (!canHandleScheme(m_url)) {
+        std::cerr << "FileSource::FileSource: ERROR: Unsupported scheme in URL \"" << m_url.toString().toStdString() << "\"" << std::endl;
+        m_errorString = tr("Unsupported scheme in URL");
+        return;
+    }
+
+    init(showProgress);
+
+    if (isRemote() &&
+        (fileOrUrl.contains('%') ||
+         fileOrUrl.contains("--"))) { // for IDNA
+
+        waitForStatus();
+
+        if (!isAvailable()) {
+            // The URL was created on the assumption that the string
+            // was human-readable.  Let's try again, this time
+            // assuming it was already encoded.
+            std::cerr << "FileSource::FileSource: Failed to retrieve URL \""
+                      << fileOrUrl.toStdString() 
+                      << "\" as human-readable URL; "
+                      << "trying again treating it as encoded URL"
+                      << std::endl;
+            m_url.setEncodedUrl(fileOrUrl.toAscii());
+            init(showProgress);
+        }
+    }
+}
+
+FileSource::FileSource(QUrl url, bool showProgress) :
+    m_url(url),
+    m_ftp(0),
+    m_http(0),
+    m_localFile(0),
+    m_ok(false),
+    m_lastStatus(0),
+    m_remote(isRemote(url.toString())),
+    m_done(false),
+    m_leaveLocalFile(false),
+    m_progressDialog(0),
+    m_progressShowTimer(this),
+    m_refCounted(false)
+{
+    std::cerr << "FileSource::FileSource(" << url.toString().toStdString() << ") [as url]" << std::endl;
+
+    if (!canHandleScheme(m_url)) {
+        std::cerr << "FileSource::FileSource: ERROR: Unsupported scheme in URL \"" << m_url.toString().toStdString() << "\"" << std::endl;
+        m_errorString = tr("Unsupported scheme in URL");
+        return;
+    }
+
+    init(showProgress);
+}
+
+FileSource::FileSource(const FileSource &rf) :
+    QObject(),
+    m_url(rf.m_url),
+    m_ftp(0),
+    m_http(0),
+    m_localFile(0),
+    m_ok(rf.m_ok),
+    m_lastStatus(rf.m_lastStatus),
+    m_remote(rf.m_remote),
+    m_done(false),
+    m_leaveLocalFile(false),
+    m_progressDialog(0),
+    m_progressShowTimer(0),
+    m_refCounted(false)
+{
+    std::cerr << "FileSource::FileSource(" << m_url.toString().toStdString() << ") [copy ctor]" << std::endl;
+
+    if (!canHandleScheme(m_url)) {
+        std::cerr << "FileSource::FileSource: ERROR: Unsupported scheme in URL \"" << m_url.toString().toStdString() << "\"" << std::endl;
+        m_errorString = tr("Unsupported scheme in URL");
+        return;
+    }
+
+    if (!isRemote()) {
+        m_localFilename = rf.m_localFilename;
+    } else {
+        QMutexLocker locker(&m_mapMutex);
+        std::cerr << "FileSource::FileSource(copy ctor): ref count is "
+                  << m_refCountMap[m_url] << std::endl;
+        if (m_refCountMap[m_url] > 0) {
+            m_refCountMap[m_url]++;
+            std::cerr << "raised it to " << m_refCountMap[m_url] << std::endl;
+            m_localFilename = m_remoteLocalMap[m_url];
+            m_refCounted = true;
+        } else {
+            m_ok = false;
+            m_lastStatus = 404;
+        }
+    }
+
+    m_done = true;
+}
+
+FileSource::~FileSource()
+{
+    std::cerr << "FileSource(" << m_url.toString().toStdString() << ")::~FileSource" << std::endl;
+
+    cleanup();
+
+    if (isRemote() && !m_leaveLocalFile) deleteCacheFile();
+}
+
+void
+FileSource::init(bool showProgress)
+{
+    if (!isRemote()) {
+        m_localFilename = m_url.toLocalFile();
+        m_ok = true;
+        if (!QFileInfo(m_localFilename).exists()) {
+            m_lastStatus = 404;
+        } else {
+            m_lastStatus = 200;
+        }
+        m_done = true;
+        return;
+    }
+
+    if (createCacheFile()) {
+        std::cerr << "FileSource::init: Already have this one" << std::endl;
+        m_ok = true;
+        if (!QFileInfo(m_localFilename).exists()) {
+            m_lastStatus = 404;
+        } else {
+            m_lastStatus = 200;
+        }
+        m_done = true;
+        return;
+    }
+
+    if (m_localFilename == "") return;
+    m_localFile = new QFile(m_localFilename);
+    m_localFile->open(QFile::WriteOnly);
+
+    QString scheme = m_url.scheme().toLower();
+
+    std::cerr << "FileSource::init: Don't have local copy of \""
+              << m_url.toString().toStdString() << "\", retrieving" << std::endl;
+
+    if (scheme == "http") {
+        initHttp();
+    } else if (scheme == "ftp") {
+        initFtp();
+    } else {
+        m_remote = false;
+        m_ok = false;
+    }
+
+    if (m_ok) {
+        
+        QMutexLocker locker(&m_mapMutex);
+
+        if (m_refCountMap[m_url] > 0) {
+            // someone else has been doing the same thing at the same time,
+            // but has got there first
+            cleanup();
+            m_refCountMap[m_url]++;
+            std::cerr << "FileSource::init: Another FileSource has got there first, abandoning our download and using theirs" << std::endl;
+            m_localFilename = m_remoteLocalMap[m_url];
+            m_refCounted = true;
+            m_ok = true;
+            if (!QFileInfo(m_localFilename).exists()) {
+                m_lastStatus = 404;
+            }
+            m_done = true;
+            return;
+        }
+
+        m_remoteLocalMap[m_url] = m_localFilename;
+        m_refCountMap[m_url]++;
+        m_refCounted = true;
+
+        if (showProgress) {
+            m_progressDialog = new QProgressDialog(tr("Downloading %1...").arg(m_url.toString()), tr("Cancel"), 0, 100);
+            m_progressDialog->hide();
+            connect(&m_progressShowTimer, SIGNAL(timeout()),
+                    this, SLOT(showProgressDialog()));
+            connect(m_progressDialog, SIGNAL(canceled()), this, SLOT(cancelled()));
+            m_progressShowTimer.setSingleShot(true);
+            m_progressShowTimer.start(2000);
+        }
+    }
+}
+
+void
+FileSource::initHttp()
+{
+    m_ok = true;
+    m_http = new QHttp(m_url.host(), m_url.port(80));
+    connect(m_http, SIGNAL(done(bool)), this, SLOT(done(bool)));
+    connect(m_http, SIGNAL(dataReadProgress(int, int)),
+            this, SLOT(dataReadProgress(int, int)));
+    connect(m_http, SIGNAL(responseHeaderReceived(const QHttpResponseHeader &)),
+            this, SLOT(httpResponseHeaderReceived(const QHttpResponseHeader &)));
+
+    // I don't quite understand this.  url.path() returns a path
+    // without percent encoding; for example, spaces appear as
+    // literal spaces.  This generally won't work if sent to the
+    // server directly.  You can retrieve a correctly encoded URL
+    // from QUrl using url.toEncoded(), but that gives you the
+    // whole URL; there doesn't seem to be any way to retrieve
+    // only an encoded path.  Furthermore there doesn't seem to be
+    // any way to convert a retrieved path into an encoded path
+    // without explicitly specifying that you don't want the path
+    // separators ("/") to be encoded.  (Besides being painful to
+    // manage, I don't see how this can work correctly in any case
+    // where a percent-encoded "/" is supposed to appear within a
+    // path element?)  There also seems to be no way to retrieve
+    // the path plus query string, i.e. everything that I need to
+    // send to the HTTP server.  And no way for QHttp to take a
+    // QUrl argument.  I'm obviously missing something.
+
+    // So, two ways to do this: query the bits from the URL,
+    // encode them individually, and glue them back together
+    // again...
+/*
+    QString path = QUrl::toPercentEncoding(m_url.path(), "/");
+    QList<QPair<QString, QString> > query = m_url.queryItems();
+    if (!query.empty()) {
+        QStringList q2;
+        for (QList<QPair<QString, QString> >::iterator i = query.begin();
+             i != query.end(); ++i) {
+            q2.push_back(QString("%1=%3")
+                         .arg(QString(QUrl::toPercentEncoding(i->first)))
+                         .arg(QString(QUrl::toPercentEncoding(i->second))));
+        }
+        path = QString("%1%2%3")
+            .arg(path).arg("?")
+            .arg(q2.join("&"));
+    }
+*/
+
+    // ...or, much simpler but relying on knowledge about the
+    // scheme://host/path/path/query etc format of the URL, we can
+    // get the whole URL ready-encoded and then split it on "/" as
+    // appropriate...
+        
+    QString path = "/" + QString(m_url.toEncoded()).section('/', 3);
+
+    std::cerr << "FileSource: path is \""
+              << path.toStdString() << "\"" << std::endl;
+        
+    m_http->get(path, m_localFile);
+}
+
+void
+FileSource::initFtp()
+{
+    m_ok = true;
+    m_ftp = new QFtp;
+    connect(m_ftp, SIGNAL(done(bool)), this, SLOT(done(bool)));
+    connect(m_ftp, SIGNAL(commandFinished(int, bool)),
+            this, SLOT(ftpCommandFinished(int, bool)));
+    connect(m_ftp, SIGNAL(dataTransferProgress(qint64, qint64)),
+            this, SLOT(dataTransferProgress(qint64, qint64)));
+    m_ftp->connectToHost(m_url.host(), m_url.port(21));
+    
+    QString username = m_url.userName();
+    if (username == "") {
+        username = "anonymous";
+    }
+    
+    QString password = m_url.password();
+    if (password == "") {
+        password = QString("%1@%2").arg(getenv("USER")).arg(getenv("HOST"));
+    }
+    
+    m_ftp->login(username, password);
+    
+    QString dirpath = m_url.path().section('/', 0, -2);
+    QString filename = m_url.path().section('/', -1);
+    
+    if (dirpath == "") dirpath = "/";
+    m_ftp->cd(dirpath);
+    m_ftp->get(filename, m_localFile);
+}
+
+void
+FileSource::cleanup()
+{
+    m_done = true;
+    if (m_http) {
+        QHttp *h = m_http;
+        m_http = 0;
+        h->abort();
+        h->deleteLater();
+    }
+    if (m_ftp) {
+        QFtp *f = m_ftp;
+        m_ftp = 0;
+        f->abort();
+        f->deleteLater();
+    }
+    delete m_progressDialog;
+    m_progressDialog = 0;
+    delete m_localFile; // does not actually delete the file
+    m_localFile = 0;
+}
+
+bool
+FileSource::isRemote(QString fileOrUrl)
+{
+    QString scheme = QUrl(fileOrUrl).scheme().toLower();
+    return (scheme == "http" || scheme == "ftp");
+}
+
+bool
+FileSource::canHandleScheme(QUrl url)
+{
+    QString scheme = url.scheme().toLower();
+    return (scheme == "http" || scheme == "ftp" ||
+            scheme == "file" || scheme == "");
+}
+
+bool
+FileSource::isAvailable()
+{
+    waitForStatus();
+    bool available = true;
+    if (!m_ok) available = false;
+    else available = (m_lastStatus / 100 == 2);
+    std::cerr << "FileSource::isAvailable: " << (available ? "yes" : "no")
+              << std::endl;
+    return available;
+}
+
+void
+FileSource::waitForStatus()
+{
+    while (m_ok && (!m_done && m_lastStatus == 0)) {
+//        std::cerr << "waitForStatus: processing (last status " << m_lastStatus << ")" << std::endl;
+        QApplication::processEvents();
+    }
+}
+
+void
+FileSource::waitForData()
+{
+    while (m_ok && !m_done) {
+        QApplication::processEvents();
+    }
+}
+
+void
+FileSource::setLeaveLocalFile(bool leave)
+{
+    m_leaveLocalFile = leave;
+}
+
+bool
+FileSource::isOK() const
+{
+    return m_ok;
+}
+
+bool
+FileSource::isDone() const
+{
+    return m_done;
+}
+
+bool
+FileSource::isRemote() const
+{
+    return m_remote;
+}
+
+QString
+FileSource::getLocation() const
+{
+    return m_url.toString();
+}
+
+QString
+FileSource::getLocalFilename() const
+{
+    return m_localFilename;
+}
+
+QString
+FileSource::getContentType() const
+{
+    return m_contentType;
+}
+
+QString
+FileSource::getExtension() const
+{
+    if (m_localFilename != "") {
+        return QFileInfo(m_localFilename).suffix().toLower();
+    } else {
+        return QFileInfo(m_url.toLocalFile()).suffix().toLower();
+    }
+}
+
+QString
+FileSource::getErrorString() const
+{
+    return m_errorString;
+}
+
+void
+FileSource::dataReadProgress(int done, int total)
+{
+    dataTransferProgress(done, total);
+}
+
+void
+FileSource::httpResponseHeaderReceived(const QHttpResponseHeader &resp)
+{
+    m_lastStatus = resp.statusCode();
+    if (m_lastStatus / 100 >= 4) {
+        m_errorString = QString("%1 %2")
+            .arg(resp.statusCode()).arg(resp.reasonPhrase());
+        std::cerr << "FileSource::responseHeaderReceived: "
+                  << m_errorString.toStdString() << std::endl;
+    } else {
+        std::cerr << "FileSource::responseHeaderReceived: "
+                  << m_lastStatus << std::endl;
+        if (resp.hasContentType()) m_contentType = resp.contentType();
+    }        
+}
+
+void
+FileSource::ftpCommandFinished(int id, bool error)
+{
+    std::cerr << "FileSource::ftpCommandFinished(" << id << ", " << error << ")" << std::endl;
+
+    if (!m_ftp) return;
+
+    QFtp::Command command = m_ftp->currentCommand();
+
+    if (!error) {
+        std::cerr << "FileSource::ftpCommandFinished: success for command "
+                  << command << std::endl;
+        return;
+    }
+
+    if (command == QFtp::ConnectToHost) {
+        m_errorString = tr("Failed to connect to FTP server");
+    } else if (command == QFtp::Login) {
+        m_errorString = tr("Login failed");
+    } else if (command == QFtp::Cd) {
+        m_errorString = tr("Failed to change to correct directory");
+    } else if (command == QFtp::Get) {
+        m_errorString = tr("FTP download aborted");
+    }
+
+    m_lastStatus = 400; // for done()
+}
+
+void
+FileSource::dataTransferProgress(qint64 done, qint64 total)
+{
+    if (!m_progressDialog) return;
+
+    int percent = int((double(done) / double(total)) * 100.0 - 0.1);
+    emit progress(percent);
+
+    if (percent > 0) {
+        m_progressDialog->setValue(percent);
+        m_progressDialog->show();
+    }
+}
+
+void
+FileSource::cancelled()
+{
+    m_done = true;
+    cleanup();
+
+    m_ok = false;
+    m_errorString = tr("Download cancelled");
+}
+
+void
+FileSource::done(bool error)
+{
+    std::cerr << "FileSource::done(" << error << ")" << std::endl;
+
+    if (m_done) return;
+
+    emit progress(100);
+
+    if (error) {
+        if (m_http) {
+            m_errorString = m_http->errorString();
+        } else if (m_ftp) {
+            m_errorString = m_ftp->errorString();
+        }
+    }
+
+    if (m_lastStatus / 100 >= 4) {
+        error = true;
+    }
+
+    cleanup();
+
+    if (!error) {
+        QFileInfo fi(m_localFilename);
+        if (!fi.exists()) {
+            m_errorString = tr("Failed to create local file %1").arg(m_localFilename);
+            error = true;
+        } else if (fi.size() == 0) {
+            m_errorString = tr("File contains no data!");
+            error = true;
+        }
+    }
+
+    if (error) {
+        std::cerr << "FileSource::done: error is " << error << ", deleting cache file" << std::endl;
+        deleteCacheFile();
+    }
+
+    m_ok = !error;
+    m_done = true;
+    emit ready();
+}
+
+void
+FileSource::deleteCacheFile()
+{
+    std::cerr << "FileSource::deleteCacheFile(\"" << m_localFilename.toStdString() << "\")" << std::endl;
+
+    cleanup();
+
+    if (m_localFilename == "") {
+        return;
+    }
+
+    if (!isRemote()) {
+        std::cerr << "not a cache file" << std::endl;
+        return;
+    }
+
+    if (m_refCounted) {
+
+        QMutexLocker locker(&m_mapMutex);
+        m_refCounted = false;
+
+        if (m_refCountMap[m_url] > 0) {
+            m_refCountMap[m_url]--;
+            std::cerr << "reduced ref count to " << m_refCountMap[m_url] << std::endl;
+            if (m_refCountMap[m_url] > 0) {
+                m_done = true;
+                return;
+            }
+        }
+    }
+
+    m_fileCreationMutex.lock();
+
+    if (!QFile(m_localFilename).remove()) {
+        std::cerr << "FileSource::deleteCacheFile: ERROR: Failed to delete file \"" << m_localFilename.toStdString() << "\"" << std::endl;
+    } else {
+        std::cerr << "FileSource::deleteCacheFile: Deleted cache file \"" << m_localFilename.toStdString() << "\"" << std::endl;
+        m_localFilename = "";
+    }
+
+    m_fileCreationMutex.unlock();
+
+    m_done = true;
+}
+
+void
+FileSource::showProgressDialog()
+{
+    if (m_progressDialog) m_progressDialog->show();
+}
+
+bool
+FileSource::createCacheFile()
+{
+    {
+        QMutexLocker locker(&m_mapMutex);
+
+        std::cerr << "FileSource::createCacheFile: refcount is " << m_refCountMap[m_url] << std::endl;
+
+        if (m_refCountMap[m_url] > 0) {
+            m_refCountMap[m_url]++;
+            m_localFilename = m_remoteLocalMap[m_url];
+            std::cerr << "raised it to " << m_refCountMap[m_url] << std::endl;
+            m_refCounted = true;
+            return true;
+        }
+    }
+
+    QDir dir;
+    try {
+        dir = TempDirectory::getInstance()->getSubDirectoryPath("download");
+    } catch (DirectoryCreationFailed f) {
+        std::cerr << "FileSource::createCacheFile: ERROR: Failed to create temporary directory: " << f.what() << std::endl;
+        return "";
+    }
+
+    QString filepart = m_url.path().section('/', -1, -1,
+                                            QString::SectionSkipEmpty);
+
+    QString extension = filepart.section('.', -1);
+    QString base = filepart;
+    if (extension != "") {
+        base = base.left(base.length() - extension.length() - 1);
+    }
+    if (base == "") base = "remote";
+
+    QString filename;
+
+    if (extension == "") {
+        filename = base;
+    } else {
+        filename = QString("%1.%2").arg(base).arg(extension);
+    }
+
+    QString filepath(dir.filePath(filename));
+
+    std::cerr << "FileSource::createCacheFile: URL is \"" << m_url.toString().toStdString() << "\", dir is \"" << dir.path().toStdString() << "\", base \"" << base.toStdString() << "\", extension \"" << extension.toStdString() << "\", filebase \"" << filename.toStdString() << "\", filename \"" << filepath.toStdString() << "\"" << std::endl;
+
+    QMutexLocker fcLocker(&m_fileCreationMutex);
+
+    ++m_count;
+
+    if (QFileInfo(filepath).exists() ||
+        !QFile(filepath).open(QFile::WriteOnly)) {
+
+        std::cerr << "FileSource::createCacheFile: Failed to create local file \""
+                  << filepath.toStdString() << "\" for URL \""
+                  << m_url.toString().toStdString() << "\" (or file already exists): appending suffix instead" << std::endl;
+
+
+        if (extension == "") {
+            filename = QString("%1_%2").arg(base).arg(m_count);
+        } else {
+            filename = QString("%1_%2.%3").arg(base).arg(m_count).arg(extension);
+        }
+        filepath = dir.filePath(filename);
+
+        if (QFileInfo(filepath).exists() ||
+            !QFile(filepath).open(QFile::WriteOnly)) {
+
+            std::cerr << "FileSource::createCacheFile: ERROR: Failed to create local file \""
+                      << filepath.toStdString() << "\" for URL \""
+                      << m_url.toString().toStdString() << "\" (or file already exists)" << std::endl;
+
+            return "";
+        }
+    }
+
+    std::cerr << "FileSource::createCacheFile: url "
+              << m_url.toString().toStdString() << " -> local filename "
+              << filepath.toStdString() << std::endl;
+    
+    m_localFilename = filepath;
+
+    return false;
+}