refactor: Get process IDs by iterating /proc. Improve readability in JsonConnection option handling. (#843)

Co-authored-by: brindosch <edeltraud70@gmx.de>

src/hyperion-aml/hyperion-aml.cpp

@@ -1,5 +1,4 @@
 
-
 // QT includes
 #include <QCoreApplication>
 #include <QImage>

src/hyperion-remote/JsonConnection.cpp

@@ -372,7 +372,6 @@ void JsonConnection::setConfig(const QString &jsonString)
 	command["command"] = QString("config");
 	command["subcommand"] = QString("setconfig");
 
-
 	if (jsonString.size() > 0)
 	{
 		QJsonObject configObj;
@@ -384,9 +383,6 @@ void JsonConnection::setConfig(const QString &jsonString)
 		command["config"] = configObj;
 	}
 
-
-
-
 	// send command message
 	QJsonObject reply = sendMessage(command);
 
@@ -423,72 +419,26 @@ void JsonConnection::setAdjustment(
 		adjust["id"] = adjustmentId;
 	}
 
-	if (redAdjustment.isValid())
+	const auto addAdjustmentIfValid = [&] (const QString & name, const QColor & adjustment) {
+		if (adjustment.isValid())
 		{
-		QJsonArray red;
-		red.append(redAdjustment.red());
-		red.append(redAdjustment.green());
-		red.append(redAdjustment.blue());
-		adjust["red"] = red;
+			QJsonArray color;
+			color.append(adjustment.red());
+			color.append(adjustment.green());
+			color.append(adjustment.blue());
+			adjust[name] = color;
 		}
+	};
 
-	if (greenAdjustment.isValid())
-	{
-		QJsonArray green;
-		green.append(greenAdjustment.red());
-		green.append(greenAdjustment.green());
-		green.append(greenAdjustment.blue());
-		adjust["green"] = green;
-	}
+	addAdjustmentIfValid("red",     redAdjustment);
+	addAdjustmentIfValid("green",   greenAdjustment);
+	addAdjustmentIfValid("blue",    blueAdjustment);
+	addAdjustmentIfValid("cyan",    cyanAdjustment);
+	addAdjustmentIfValid("magenta", magentaAdjustment);
+	addAdjustmentIfValid("yellow",  yellowAdjustment);
+	addAdjustmentIfValid("white",   whiteAdjustment);
+	addAdjustmentIfValid("black",   blackAdjustment);
 
-	if (blueAdjustment.isValid())
-	{
-		QJsonArray blue;
-		blue.append(blueAdjustment.red());
-		blue.append(blueAdjustment.green());
-		blue.append(blueAdjustment.blue());
-		adjust["blue"] = blue;
-	}
-	if (cyanAdjustment.isValid())
-	{
-		QJsonArray cyan;
-		cyan.append(cyanAdjustment.red());
-		cyan.append(cyanAdjustment.green());
-		cyan.append(cyanAdjustment.blue());
-		adjust["cyan"] = cyan;
-	}
-	if (magentaAdjustment.isValid())
-	{
-		QJsonArray magenta;
-		magenta.append(magentaAdjustment.red());
-		magenta.append(magentaAdjustment.green());
-		magenta.append(magentaAdjustment.blue());
-		adjust["magenta"] = magenta;
-	}
-	if (yellowAdjustment.isValid())
-	{
-		QJsonArray yellow;
-		yellow.append(yellowAdjustment.red());
-		yellow.append(yellowAdjustment.green());
-		yellow.append(yellowAdjustment.blue());
-		adjust["yellow"] = yellow;
-	}
-	if (whiteAdjustment.isValid())
-	{
-		QJsonArray white;
-		white.append(whiteAdjustment.red());
-		white.append(whiteAdjustment.green());
-		white.append(whiteAdjustment.blue());
-		adjust["white"] = white;
-	}
-	if (blackAdjustment.isValid())
-	{
-		QJsonArray black;
-		black.append(blackAdjustment.red());
-		black.append(blackAdjustment.green());
-		black.append(blackAdjustment.blue());
-		adjust["black"] = black;
-	}
 	if (backlightThreshold != nullptr)
 	{
 		adjust["backlightThreshold"] = *backlightThreshold;

src/hyperiond/detectProcess.h

@@ -1,8 +1,11 @@
 #pragma once
 
-#include <QString>
-#include <QProcess>
 #include <QByteArray>
+#include <QDir>
+#include <QFile>
+#include <QRegExp>
+#include <QString>
+#include <QTextStream>
 
 #ifdef WIN32
 // psapi.h requires windows.h to be included
@@ -12,7 +15,6 @@
 
 unsigned int getProcessIdsByProcessName(const char *processName, QStringList &listOfPids)
 {
-
 	// Clear content of returned list of PIDS
 	listOfPids.clear();
 
@@ -57,33 +59,36 @@ unsigned int getProcessIdsByProcessName(const char *processName, QStringList &li
 		}
 	}
 
-	return listOfPids.count();
-
 #else
 
-	// Run pgrep, which looks through the currently running processses and lists the process IDs
-	// which match the selection criteria to stdout.
-	QProcess process;
-	process.start("pgrep", QStringList() << processName);
-	process.waitForReadyRead();
+	QDir dir("/proc");
+	dir.setFilter(QDir::Dirs);
+	dir.setSorting(QDir::Name | QDir::Reversed);
 
-	QByteArray bytes = process.readAllStandardOutput();
+	for (const QString & pid : dir.entryList()) {
+		QRegExp regexp("\\d*");
+		if (!regexp.exactMatch(pid))
+		{
+			/* Not a number, can not be PID */
+			continue;
+		}
 
-	process.terminate();
-	process.waitForFinished();
-	process.kill();
+		QFile cmdline("/proc/" + pid + "/cmdline");
+		if (!cmdline.open(QFile::ReadOnly | QFile::Text))
+		{
+			/* Can not open cmdline file */
+			continue;
+		}
 
-	// Output is something like "2472\n2323" for multiple instances
-	if (bytes.isEmpty())
-		return 0;
-
-	#if (QT_VERSION >= QT_VERSION_CHECK(5, 14, 0))
-		listOfPids = QString(bytes).split("\n", Qt::SkipEmptyParts);
-	#else
-		listOfPids = QString(bytes).split("\n", QString::SkipEmptyParts);
-	#endif
-
-	return listOfPids.count();
+		QTextStream in(&cmdline);
+		QString command = in.readAll();
+		if (command.startsWith(processName))
+		{
+			listOfPids.push_back(pid);
+		}
+	}
 
 #endif
+
+	return listOfPids.count();
 }

src/hyperiond/main.cpp

@@ -153,7 +153,6 @@ int main(int argc, char** argv)
 	Logger::setLogLevel(Logger::WARNING);
 
 	// check if we are running already an instance
-	// TODO Do not use pgrep on linux, instead iter /proc
 	// TODO Allow one session per user
 	// http://www.qtcentre.org/threads/44489-Get-Process-ID-for-a-running-application
 	QStringList listOfPids;