Add path check for channel buffer cleanup

Author: PascalBoeschoten

src/Driver.cxx

@@ -33,32 +33,34 @@ void freeUnusedChannelBuffers()
 
   try {
     std::string pciPath = "/sys/bus/pci/drivers/uio_pci_dma/";
-    for (auto &entry : boost::make_iterator_range(bfs::directory_iterator(pciPath), {})) {
-      auto filename = entry.path().filename().string();
-      if (filename.size() == 12) {
-        // The PCI directory names are 12 characters long
-        auto pciAddress = filename.substr(5); // Remove leading '0000:'
+    if (boost::filesystem::exists(pciPath)) {
+      for (auto &entry : boost::make_iterator_range(bfs::directory_iterator(pciPath), {})) {
+        auto filename = entry.path().filename().string();
+        if (filename.size() == 12) {
+          // The PCI directory names are 12 characters long
+          auto pciAddress = filename.substr(5); // Remove leading '0000:'
 
-        if (PciAddress::fromString(pciAddress)) {
-          // This is a valid PCI address
-          std::string dmaPath("/sys/bus/pci/drivers/uio_pci_dma/" + filename + "/dma");
-          for (auto &entry : boost::make_iterator_range(bfs::directory_iterator(dmaPath), {})) {
-            auto bufferId = entry.path().filename().string();
-            if (bfs::is_directory(entry)) {
-              std::string mapPath = dmaPath + "/" + bufferId + "/map";
-              std::string freePath = dmaPath + "/free";
-              auto fuserResult = AliceO2::Common::System::executeCommand("fuser " + mapPath);
-              if (fuserResult.empty()) {
-                // No process is using it, we can free the buffer!
-                logger << "Freeing PDA buffer '" + mapPath + "'" << InfoLogger::InfoLogger::endm;
-                auto fuserResult = AliceO2::Common::System::executeCommand("echo " + bufferId + " > " + freePath);
+          if (PciAddress::fromString(pciAddress)) {
+            // This is a valid PCI address
+            std::string dmaPath("/sys/bus/pci/drivers/uio_pci_dma/" + filename + "/dma");
+            for (auto &entry : boost::make_iterator_range(bfs::directory_iterator(dmaPath), {})) {
+              auto bufferId = entry.path().filename().string();
+              if (bfs::is_directory(entry)) {
+                std::string mapPath = dmaPath + "/" + bufferId + "/map";
+                std::string freePath = dmaPath + "/free";
+                auto fuserResult = AliceO2::Common::System::executeCommand("fuser " + mapPath);
+                if (fuserResult.empty()) {
+                  // No process is using it, we can free the buffer!
+                  logger << "Freeing PDA buffer '" + mapPath + "'" << InfoLogger::InfoLogger::endm;
+                  auto fuserResult = AliceO2::Common::System::executeCommand("echo " + bufferId + " > " + freePath);
+                }
               }
             }
           }
         }
       }
     }
-  } catch (const boost::filesystem::filesystem_error& e) {
+  } catch (const boost::filesystem::filesystem_error &e) {
     logger << "Failed to free buffers: " << e.what() << InfoLogger::InfoLogger::endm;
     throw;
   }