Skeleton code for a non-blocking UI thread for downloading dives from the DC

This is the skeleton code for a non-blocking ui-thread
It already creates the first-thread ( 'do not block the ui' )
and the second thread ('download from the dive computer')
We can in the future merge both in the same place - I didn't
want to do that now because the download function is written
in the libdivecomputer.c code, and I cant just transform that
to a QThread and use signals, so I used two threads for that.

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>

Makefile

@@ -45,6 +45,7 @@ HEADERS = \
 	qt-ui/profilegraphics.h \
 	qt-ui/globe.h \
 	qt-ui/kmessagewidget.h \
+	qt-ui/downloadfromdivecomputer.h \
 
 
 SOURCES = \
@@ -64,6 +65,7 @@ SOURCES = \
 	sha1.c \
 	statistics.c \
 	time.c \
+	libdivecomputer.c \
 	qt-gui.cpp \
 	qt-ui/addcylinderdialog.cpp \
 	qt-ui/addweightsystemdialog.cpp \
@@ -77,6 +79,7 @@ SOURCES = \
 	qt-ui/profilegraphics.cpp \
 	qt-ui/globe.cpp \
 	qt-ui/kmessagewidget.cpp \
+	qt-ui/downloadfromdivecomputer.cpp \
 	$(RESFILE)
 
 

download-dialog.c

@@ -3,24 +3,12 @@
 #include "dive.h"
 #include "divelist.h"
 #include "display.h"
-#if USE_GTK_UI
-#include "display-gtk.h"
-#include "callbacks-gtk.h"
-#endif
 #include "libdivecomputer.h"
 
 const char *default_dive_computer_vendor;
 const char *default_dive_computer_product;
 const char *default_dive_computer_device;
 
-#if USE_GTK_UI
-static gboolean force_download;
-static gboolean prefer_downloaded;
-
-OPTIONCALLBACK(force_toggle, force_download)
-OPTIONCALLBACK(prefer_dl_toggle, prefer_downloaded)
-#endif
-
 struct product {
 	const char *product;
 	dc_descriptor_t *descriptor;

libdivecomputer.c

@@ -1,5 +1,4 @@
 #include <stdio.h>
-#include <pthread.h>
 #include <unistd.h>
 #include <inttypes.h>
 #include <glib/gi18n.h>
@@ -21,8 +20,9 @@
   #define NOT_FROG
 #endif
 
-static const char *progress_bar_text = "";
+const char *progress_bar_text = "";
-static double progress_bar_fraction = 0.0;
+double progress_bar_fraction = 0.0;
+
 static int stoptime, stopdepth, ndl, po2, cns;
 static gboolean in_deco, first_temp_is_air;
 
@@ -686,7 +686,7 @@ static const char *do_device_import(device_data_t *data)
 	return NULL;
 }
 
-static const char *do_libdivecomputer_import(device_data_t *data)
+const char *do_libdivecomputer_import(device_data_t *data)
 {
 	dc_status_t rc;
 	const char *err;
@@ -709,70 +709,3 @@ static const char *do_libdivecomputer_import(device_data_t *data)
 	dc_context_free(data->context);
 	return err;
 }
-
-#if USE_GTK_UI
-static void *pthread_wrapper(void *_data)
-{
-	device_data_t *data = _data;
-	const char *err_string = do_libdivecomputer_import(data);
-	import_thread_done = 1;
-	return (void *)err_string;
-}
-
-/* this simply ends the dialog without a response and asks not to be fired again
- * as we set this function up in every loop while uemis_download is waiting for
- * the download to finish */
-static gboolean timeout_func(gpointer _data)
-{
-	GtkDialog *dialog = _data;
-	if (!import_thread_cancelled)
-		gtk_dialog_response(dialog, GTK_RESPONSE_NONE);
-	return FALSE;
-}
-
-GError *do_import(device_data_t *data)
-{
-	pthread_t pthread;
-	void *retval;
-	GtkDialog *dialog = data->dialog;
-
-	/* I'm sure there is some better interface for waiting on a thread in a UI main loop */
-	import_thread_done = 0;
-	progress_bar_text = "";
-	progress_bar_fraction = 0.0;
-	pthread_create(&pthread, NULL, pthread_wrapper, data);
-	/* loop here until the import is done or was cancelled by the user;
-	 * in order to get control back from gtk we register a timeout function
-	 * that ends the dialog with no response every 100ms; we then update the
-	 * progressbar and setup the timeout again - unless of course the user
-	 * pressed cancel, in which case we just wait for the download thread
-	 * to react to that and exit */
-	while (!import_thread_done) {
-		if (!import_thread_cancelled) {
-			int result;
-			g_timeout_add(100, timeout_func, dialog);
-			update_progressbar(&data->progress, progress_bar_fraction);
-			update_progressbar_text(&data->progress, progress_bar_text);
-			result = gtk_dialog_run(dialog);
-			switch (result) {
-			case GTK_RESPONSE_CANCEL:
-				import_thread_cancelled = TRUE;
-				progress_bar_text = _("Cancelled...");
-				break;
-			default:
-				/* nothing */
-				break;
-			}
-		} else {
-			update_progressbar(&data->progress, progress_bar_fraction);
-			update_progressbar_text(&data->progress, progress_bar_text);
-			usleep(100000);
-		}
-	}
-	if (pthread_join(pthread, &retval) < 0)
-		retval = _("Odd pthread error return");
-	if (retval)
-		return error(retval, data->vendor, data->product, data->devname);
-	return NULL;
-}
-#endif

libdivecomputer.h

@@ -1,6 +1,11 @@
 #ifndef LIBDIVECOMPUTER_H
 #define LIBDIVECOMPUTER_H
 
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /* libdivecomputer */
 #include <libdivecomputer/version.h>
 #include <libdivecomputer/device.h>
@@ -20,12 +25,12 @@ typedef struct device_data_t {
 	dc_context_t *context;
 	int preexisting;
 	gboolean force_download;
-#if USE_GTK_UI
-	progressbar_t progress;
-	GtkDialog *dialog;
-#endif
 } device_data_t;
 
-extern GError *do_import(device_data_t *data);
+const char *do_libdivecomputer_import(device_data_t *data);
+
+#ifdef __cplusplus
+}
+#endif
 
 #endif

qt-ui/downloadfromdivecomputer.cpp

@@ -0,0 +1,73 @@
+#include "downloadfromdivecomputer.h"
+#include "ui_downloadfromdivecomputer.h"
+
+#include "../libdivecomputer.h"
+
+#include <QThread>
+#include <QDebug>
+
+namespace DownloadFromDcGlobal{
+	const char *err_string;
+};
+
+extern const char *progress_bar_text;
+extern double progress_bar_fraction;
+
+DownloadFromDCWidget::DownloadFromDCWidget(QWidget* parent, Qt::WindowFlags f) :
+	QDialog(parent, f), ui(new Ui::DownloadFromDiveComputer), thread(0)
+{
+	ui->setupUi(this);
+	ui->progressBar->hide();
+	ui->progressBar->setMinimum(0);
+	ui->progressBar->setMaximum(100);
+}
+
+void DownloadFromDCWidget::on_cancel_clicked()
+{
+	close();
+}
+
+void DownloadFromDCWidget::on_ok_clicked()
+{
+
+	ui->progressBar->setValue(0);
+	ui->progressBar->show();
+
+	if(thread){
+		thread->deleteLater();
+	}
+
+	device_data_t data;
+	// still need to fill the data info here.
+	thread = new InterfaceThread(this, &data);
+	connect(thread, SIGNAL(updateInterface(int)), ui->progressBar, SLOT(setValue(int)), Qt::QueuedConnection); // Qt::QueuedConnection == threadsafe.
+	connect(thread, SIGNAL(updateInterface(int)), this, SLOT(setValue(int)), Qt::QueuedConnection); // Qt::QueuedConnection == threadsafe.
+	thread->start();
+}
+
+DownloadThread::DownloadThread(device_data_t* data): data(data)
+{
+}
+
+void DownloadThread::run()
+{
+	do_libdivecomputer_import(data);
+	qDebug() << "Download thread started";
+}
+
+InterfaceThread::InterfaceThread(QObject* parent, device_data_t* data): QThread(parent), data(data)
+{
+
+}
+
+void InterfaceThread::run()
+{
+	DownloadThread *download = new DownloadThread(data);
+
+	download->start();
+ 	while(download->isRunning()){
+		msleep(200);
+ 		updateInterface(progress_bar_fraction *100);
+ 	}
+	updateInterface(100);
+}

qt-ui/downloadfromdivecomputer.h

@@ -0,0 +1,46 @@
+#ifndef DOWNLOADFROMDIVECOMPUTER_H
+#define DOWNLOADFROMDIVECOMPUTER_H
+#include <QDialog>
+#include <QThread>
+
+namespace Ui{
+	class DownloadFromDiveComputer;
+}
+struct device_data_t;
+
+class DownloadThread : public QThread{
+	Q_OBJECT
+public:
+    explicit DownloadThread(device_data_t* data);
+    virtual void run();
+private:
+	device_data_t *data;
+};
+
+class InterfaceThread : public QThread{
+	Q_OBJECT
+public:
+	InterfaceThread(QObject *parent, device_data_t *data) ;
+    virtual void run();
+
+Q_SIGNALS:
+	void updateInterface(int value);
+private:
+	device_data_t *data;
+};
+
+class DownloadFromDCWidget : public QDialog{
+	Q_OBJECT
+public:
+    explicit DownloadFromDCWidget(QWidget* parent = 0, Qt::WindowFlags f = 0);
+
+public slots:
+	void on_ok_clicked();
+	void on_cancel_clicked();
+private:
+	Ui::DownloadFromDiveComputer *ui;
+	InterfaceThread *thread;
+};
+
+
+#endif

qt-ui/downloadfromdivecomputer.ui

@@ -0,0 +1,110 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>DownloadFromDiveComputer</class>
+ <widget class="QDialog" name="DownloadFromDiveComputer">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>331</width>
+    <height>199</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Form</string>
+  </property>
+  <layout class="QGridLayout" name="gridLayout">
+   <item row="0" column="0">
+    <widget class="QLabel" name="label">
+     <property name="text">
+      <string>Vendor</string>
+     </property>
+    </widget>
+   </item>
+   <item row="0" column="1" colspan="2">
+    <widget class="QLabel" name="label_2">
+     <property name="text">
+      <string>Dive Computer</string>
+     </property>
+    </widget>
+   </item>
+   <item row="1" column="0">
+    <widget class="QComboBox" name="vendor"/>
+   </item>
+   <item row="1" column="1" colspan="2">
+    <widget class="QComboBox" name="diveComputerName"/>
+   </item>
+   <item row="2" column="0" colspan="3">
+    <widget class="QLabel" name="label_3">
+     <property name="text">
+      <string>Device or Mount Point</string>
+     </property>
+    </widget>
+   </item>
+   <item row="3" column="0" colspan="2">
+    <widget class="QLineEdit" name="mountPoint"/>
+   </item>
+   <item row="3" column="2">
+    <widget class="QToolButton" name="search">
+     <property name="text">
+      <string>...</string>
+     </property>
+    </widget>
+   </item>
+   <item row="4" column="0" colspan="3">
+    <widget class="QCheckBox" name="forceDownload">
+     <property name="text">
+      <string>Force download of all dives</string>
+     </property>
+    </widget>
+   </item>
+   <item row="5" column="0" colspan="3">
+    <widget class="QCheckBox" name="preferDownloaded">
+     <property name="text">
+      <string>Always prefer downloaded dives</string>
+     </property>
+    </widget>
+   </item>
+   <item row="6" column="0" colspan="3">
+    <layout class="QHBoxLayout" name="horizontalLayout">
+     <item>
+      <spacer name="horizontalSpacer">
+       <property name="orientation">
+        <enum>Qt::Horizontal</enum>
+       </property>
+       <property name="sizeHint" stdset="0">
+        <size>
+         <width>40</width>
+         <height>20</height>
+        </size>
+       </property>
+      </spacer>
+     </item>
+     <item>
+      <widget class="QPushButton" name="ok">
+       <property name="text">
+        <string>OK</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QPushButton" name="cancel">
+       <property name="text">
+        <string>Cancel</string>
+       </property>
+      </widget>
+     </item>
+    </layout>
+   </item>
+   <item row="7" column="0" colspan="3">
+    <widget class="QProgressBar" name="progressBar">
+     <property name="value">
+      <number>24</number>
+     </property>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>

qt-ui/mainwindow.cpp

@@ -25,6 +25,7 @@
 #include "../pref.h"
 #include "modeldelegates.h"
 #include "models.h"
+#include "downloadfromdivecomputer.h"
 
 static MainWindow* instance = 0;
 
@@ -160,7 +161,8 @@ void MainWindow::on_actionQuit_triggered()
 
 void MainWindow::on_actionDownloadDC_triggered()
 {
-	qDebug("actionDownloadDC");
+	DownloadFromDCWidget* downloadWidget = new DownloadFromDCWidget();
+	downloadWidget->show();
 }
 
 void MainWindow::on_actionDownloadWeb_triggered()