From 3b0d63f09b6bfc5de215e27eef8a5934eb4d3851 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Sat, 19 Nov 2022 13:52:09 +0200
Subject: [PATCH] Add functions to look up subdevices of composite input
 devices

---
 source/input/device.cpp | 12 ++++++++++++
 source/input/device.h   |  2 ++
 source/input/hub.cpp    | 22 ++++++++++++++++++++++
 source/input/hub.h      |  3 +++
 4 files changed, 39 insertions(+)

diff --git a/source/input/device.cpp b/source/input/device.cpp
index 452af22..d5b3b86 100644
--- a/source/input/device.cpp
+++ b/source/input/device.cpp
@@ -1,6 +1,8 @@
 #include <msp/strings/format.h>
 #include "device.h"
 
+using namespace std;
+
 namespace Msp {
 namespace Input {
 
@@ -11,6 +13,16 @@ Device::Device(DeviceType t):
 Device::~Device()
 { }
 
+Device *Device::find_subdevice(const string &n)
+{
+	return (n==name ? this : 0);
+}
+
+Device *Device::find_subdevice(DeviceType t, unsigned i)
+{
+	return (t==type && i==0 ? this : 0);
+}
+
 bool Device::get_button_state(unsigned btn) const
 {
 	if(btn>=buttons.size())
diff --git a/source/input/device.h b/source/input/device.h
index 853ec96..4544776 100644
--- a/source/input/device.h
+++ b/source/input/device.h
@@ -69,6 +69,8 @@ public:
 
 	DeviceType get_type() const { return type; }
 	const std::string &get_name() const { return name; }
+	virtual Device *find_subdevice(DeviceType, unsigned = 0);
+	virtual Device *find_subdevice(const std::string &);
 	bool get_button_state(unsigned) const;
 	float get_axis_value(unsigned) const;
 
diff --git a/source/input/hub.cpp b/source/input/hub.cpp
index b83d10d..e45cd65 100644
--- a/source/input/hub.cpp
+++ b/source/input/hub.cpp
@@ -25,6 +25,28 @@ void Hub::attach(Device &dev)
 	dev.signal_axis_motion.connect(sigc::bind_return(sigc::bind(sigc::mem_fun(this, &Hub::axis_motion), index), false));
 }
 
+Device *Hub::find_subdevice(DeviceType t, unsigned n)
+{
+	for(vector<Device *>::const_iterator i=devices.begin(); i!=devices.end(); ++i)
+		if(Device *dev = (*i)->find_subdevice(t, 0))
+		{
+			if(!n)
+				return dev;
+			--n;
+		}
+	return 0;
+}
+
+Device *Hub::find_subdevice(const string &n)
+{
+	if(n==name)
+		return this;
+	for(vector<Device *>::const_iterator i=devices.begin(); i!=devices.end(); ++i)
+		if(Device *dev = (*i)->find_subdevice(n))
+			return dev;
+	return 0;
+}
+
 std::string Hub::get_button_name(unsigned btn) const
 {
 	unsigned dev_index = btn>>8;
diff --git a/source/input/hub.h b/source/input/hub.h
index b89196e..55d5876 100644
--- a/source/input/hub.h
+++ b/source/input/hub.h
@@ -23,6 +23,9 @@ public:
 	/// Attaches an input device to the hub.
 	void attach(Device &dev);
 
+	virtual Device *find_subdevice(DeviceType, unsigned = 0);
+	virtual Device *find_subdevice(const std::string &);
+
 	virtual std::string get_button_name(unsigned) const;
 	virtual std::string get_axis_name(unsigned) const;
 protected:
-- 
2.43.0