Support Wayland monitor selection by connector name

src/platform/linux/wlgrab.cpp

@@ -3,6 +3,7 @@
  * @brief Definitions for wlgrab capture.
  */
 // standard includes
+#include <algorithm>
 #include <thread>
 
 // local includes
@@ -57,6 +58,30 @@ namespace wl {
 
         if (streamedMonitor >= 0 && streamedMonitor < interface.monitors.size()) {
           monitor = interface.monitors[streamedMonitor].get();
+        } else {
+          auto by_name = std::find_if(
+            std::begin(interface.monitors),
+            std::end(interface.monitors),
+            [&display_name](const auto &candidate) {
+              return candidate->name == display_name;
+            });
+
+          if (by_name != std::end(interface.monitors)) {
+            monitor = by_name->get();
+          } else {
+            auto by_description = std::find_if(
+              std::begin(interface.monitors),
+              std::end(interface.monitors),
+              [&display_name](const auto &candidate) {
+                return candidate->description == display_name;
+              });
+
+            if (by_description != std::end(interface.monitors)) {
+              monitor = by_description->get();
+            } else {
+              BOOST_LOG(warning) << "No Wayland monitor matched output_name='"sv << display_name << "'; falling back to monitor 0"sv;
+            }
+          }
         }
       }
 
@@ -431,8 +456,12 @@ namespace platf {
 
       BOOST_LOG(info) << "Monitor " << x << " is "sv << monitor->name << ": "sv << monitor->description;
 
-      display_names.emplace_back(std::to_string(x));
+      if (!monitor->name.empty()) {
-    }
+        display_names.emplace_back(monitor->name);
+      } else {
+        display_names.emplace_back(std::to_string(x));
+      }
+      }
 
     BOOST_LOG(info) << "--------- End of Wayland monitor list ---------"sv;