From: Mikko Rasa <tdb@tdb.fi>
Date: Fri, 4 Dec 2015 09:36:07 +0000 (+0200)
Subject: Make ResourceManager thread-safe
X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=commitdiff_plain;h=5ef508ffc324d4f00239555c0566e4c1f2c9c5c4

Make ResourceManager thread-safe

Since a big part of the class is loading resources asynchronously, it
makes sense that resources can also be created from another thread.
---

diff --git a/source/resourcemanager.cpp b/source/resourcemanager.cpp
index bcc4839b..52e5866a 100644
--- a/source/resourcemanager.cpp
+++ b/source/resourcemanager.cpp
@@ -66,12 +66,20 @@ void ResourceManager::set_max_retain_frames(unsigned f)
 
 void ResourceManager::add_resource(Resource &r)
 {
+	MutexLock lock(map_mutex);
 	insert_unique(resources, &r, ManagedResource(r));
 }
 
-void *ResourceManager::get_data_for_resource(const Resource &r)
+const ResourceManager::ManagedResource &ResourceManager::get_managed_resource(const Resource &r) const
 {
-	return &get_item(resources, &r);
+	MutexLock lock(map_mutex);
+	return get_item(resources, &r);
+}
+
+ResourceManager::ManagedResource &ResourceManager::get_managed_resource(const Resource &r)
+{
+	MutexLock lock(map_mutex);
+	return get_item(resources, &r);
 }
 
 void ResourceManager::set_resource_location(Resource &r, DataFile::Collection &c, const string &n)
@@ -81,8 +89,11 @@ void ResourceManager::set_resource_location(Resource &r, DataFile::Collection &c
 
 void ResourceManager::set_resource_location(Resource &r, const ResourceLocation &l)
 {
-	ManagedResource &managed = get_item(resources, &r);
-	managed.location = l;
+	{
+		MutexLock lock(map_mutex);
+		ManagedResource &managed = get_item(resources, &r);
+		managed.location = l;
+	}
 
 	if(policy==LOAD_IMMEDIATELY)
 		load_resource(r);
@@ -90,13 +101,13 @@ void ResourceManager::set_resource_location(Resource &r, const ResourceLocation
 
 const ResourceManager::ResourceLocation *ResourceManager::get_resource_location(const Resource &r) const
 {
-	const ManagedResource &managed = get_item(resources, &r);
+	const ManagedResource &managed = get_managed_resource(r);
 	return managed.location.collection ? &managed.location : 0;
 }
 
 void ResourceManager::load_resource(Resource &r)
 {
-	ManagedResource &managed = get_item(resources, &r);
+	ManagedResource &managed = get_managed_resource(r);
 	if(!managed.location.collection)
 		throw runtime_error("no location");
 
@@ -139,7 +150,7 @@ void ResourceManager::resource_used(const Resource &r)
 
 void ResourceManager::remove_resource(Resource &r)
 {
-	ManagedResource &managed = get_item(resources, &r);
+	ManagedResource &managed = get_managed_resource(r);
 	ManagedResource::State state = managed.state;
 	if(state==ManagedResource::LOAD_QUEUED)
 	{
@@ -149,17 +160,19 @@ void ResourceManager::remove_resource(Resource &r)
 	}
 	else if(state>ManagedResource::LOAD_QUEUED && state<ManagedResource::LOADED)
 		thread.remove_resource(managed);
+
+	MutexLock lock(map_mutex);
 	remove_existing(resources, &r);
 }
 
 void ResourceManager::watch_resource(const Resource &r, ResourceWatcher &w)
 {
-	get_item(resources, &r).add_watcher(w);
+	get_managed_resource(r).add_watcher(w);
 }
 
 void ResourceManager::unwatch_resource(const Resource &r, ResourceWatcher &w)
 {
-	get_item(resources, &r).remove_watcher(w);
+	get_managed_resource(r).remove_watcher(w);
 }
 
 void ResourceManager::tick()
@@ -175,6 +188,7 @@ void ResourceManager::tick()
 
 	if(do_unload)
 	{
+		MutexLock lock(map_mutex);
 		if(max_retain_frames && frame>=next_unload)
 		{
 			unload_by_age();
@@ -224,7 +238,7 @@ void ResourceManager::unload_by_size()
 {
 	unsigned unload_limit = frame-min_retain_frames;
 
-	while(get_total_data_size()>size_limit)
+	while(get_total_data_size_()>size_limit)
 	{
 		ManagedResource *best = 0;
 		UInt64 best_impact = 0;
@@ -246,7 +260,7 @@ void ResourceManager::unload_by_size()
 	}
 }
 
-UInt64 ResourceManager::get_total_data_size() const
+UInt64 ResourceManager::get_total_data_size_() const
 {
 	UInt64 total = 0;
 	for(ResourceMap::const_iterator i=resources.begin(); i!=resources.end(); ++i)
@@ -255,6 +269,12 @@ UInt64 ResourceManager::get_total_data_size() const
 	return total;
 }
 
+UInt64 ResourceManager::get_total_data_size() const
+{
+	MutexLock lock(map_mutex);
+	return get_total_data_size_();
+}
+
 bool ResourceManager::age_order(ManagedResource *mr1, ManagedResource *mr2)
 {
 	return mr1->last_used>mr2->last_used;
diff --git a/source/resourcemanager.h b/source/resourcemanager.h
index 399d479a..9378d920 100644
--- a/source/resourcemanager.h
+++ b/source/resourcemanager.h
@@ -114,6 +114,7 @@ private:
 
 	LoadingPolicy policy;
 	bool async_loads;
+	mutable Mutex map_mutex;
 	ResourceMap resources;
 	LoadQueue queue;
 	UInt64 size_limit;
@@ -134,7 +135,11 @@ public:
 	void set_max_retain_frames(unsigned);
 
 	void add_resource(Resource &);
-	void *get_data_for_resource(const Resource &);
+private:
+	const ManagedResource &get_managed_resource(const Resource &) const;
+	ManagedResource &get_managed_resource(const Resource &);
+public:
+	void *get_data_for_resource(const Resource &r) { return &get_managed_resource(r); }
 	void set_resource_location(Resource &, DataFile::Collection &, const std::string &);
 	void set_resource_location(Resource &, const ResourceLocation &);
 	const ResourceLocation *get_resource_location(const Resource &) const;
@@ -151,6 +156,7 @@ private:
 	void dispatch_work();
 	void unload_by_age();
 	void unload_by_size();
+	UInt64 get_total_data_size_() const;
 public:
 	UInt64 get_total_data_size() const;