inputfile.cpp

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/*
 * This file is part of the PulseView project.
 *
 * Copyright (C) 2015 Joel Holdsworth <joel@airwebreathe.org.uk>
 *
 * 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.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#include <cassert>
#include <fstream>
#include <vector>

#include <QDebug>
#include <QString>

#include <pv/globalsettings.hpp>

#include "inputfile.hpp"

using sigrok::InputFormat;

using std::map;
using std::out_of_range;
using std::pair;
using std::shared_ptr;
using std::streamsize;
using std::string;
using std::ifstream;
using std::ios;
using std::vector;

namespace pv {
namespace devices {

// Use a 4MB chunk size for reading a file into memory. Larger values don't
// seem to provide any substancial performance improvements, but can cause
// UI lag and a visually "stuttering" display of the data currently loading.
const streamsize InputFile::BufferSize = (4 * 1024 * 1024);

InputFile::InputFile(const shared_ptr<sigrok::Context> &context,
    const string &file_name,
    shared_ptr<sigrok::InputFormat> format,
    const map<string, Glib::VariantBase> &options) :
    File(file_name),
    context_(context),
    format_(format),
    options_(options),
    interrupt_(false)
{
}

InputFile::InputFile(const shared_ptr<sigrok::Context> &context,
    QSettings &settings):
    File(""),
    context_(context),
    interrupt_(false)
{
    file_name_ = settings.value("filename").toString().toStdString();

    QString format_name = settings.value("format").toString();

    // Find matching format
    const map<string, shared_ptr<InputFormat> > formats = context->input_formats();

    try {
        format_ = formats.at(format_name.toStdString());

        // Restore all saved options
        int options = settings.value("options").toInt();

        for (int i = 0; i < options; i++) {
            settings.beginGroup("option" + QString::number(i));
            QString name = settings.value("name").toString();
            options_[name.toStdString()] = GlobalSettings::restore_variantbase(settings);
            settings.endGroup();
        }

    } catch (out_of_range&) {
        qWarning() << "Could not find input format" << format_name <<
            "needed to restore session input file";
    }
}

void InputFile::save_meta_to_settings(QSettings &settings)
{
    settings.setValue("filename", QString::fromStdString(file_name_));

    settings.setValue("format", QString::fromStdString(format_->name()));

    settings.setValue("options", (int)options_.size());

    int i = 0;
    for (const pair<const string, Glib::VariantBase>& option : options_) {
        settings.beginGroup("option" + QString::number(i));
        settings.setValue("name", QString::fromStdString(option.first));
        GlobalSettings::store_variantbase(settings, option.second);
        settings.endGroup();
        i++;
    }
}

void InputFile::open()
{
    if (session_)
        close();
    else
        session_ = context_->create_session();

    if (!format_)
        return;

    input_ = format_->create_input(options_);

    if (!input_)
        throw QString("Failed to create input");

    // open() should add the input device to the session but
    // we can't open the device without sending some data first
    f = new ifstream(file_name_, ios::binary);

    vector<char> buffer(BufferSize);

    f->read(buffer.data(), BufferSize);
    const streamsize size = f->gcount();

    if (size == 0)
        throw QString("Failed to read file");

    input_->send(buffer.data(), size);

    try {
        device_ = input_->device();
    } catch (sigrok::Error& e) {
        throw e;
    }

    session_->add_device(device_);
}

void InputFile::close()
{
    if (session_)
        session_->remove_devices();
}

void InputFile::start()
{
}

void InputFile::run()
{
    if (!input_)
        return;

    if (!f) {
        // Previous call to run() processed the entire file already
        f = new ifstream(file_name_, ios::binary);
        input_->reset();
    }

    vector<char> buffer(BufferSize);

    interrupt_ = false;
    while (!interrupt_ && !f->eof()) {
        f->read(buffer.data(), BufferSize);
        const streamsize size = f->gcount();
        if (size == 0)
            break;

        input_->send(buffer.data(), size);

        if (size != BufferSize)
            break;
    }

    input_->end();

    delete f;
    f = nullptr;
}

void InputFile::stop()
{
    interrupt_ = true;
}

} // namespace devices
} // namespace pv