From 7dfe705717eb8a39df47db84daafdb2cc16ac55e Mon Sep 17 00:00:00 2001
From: James Turner <zakalawe@mac.com>
Date: Mon, 28 May 2018 21:57:31 +0200
Subject: [PATCH] Resource manager clean-up code

---
 simgear/misc/ResourceManager.cxx | 34 +++++++++++++++++++++++++++-----
 simgear/misc/ResourceManager.hxx | 12 ++++++++---
 2 files changed, 38 insertions(+), 8 deletions(-)

diff --git a/simgear/misc/ResourceManager.cxx b/simgear/misc/ResourceManager.cxx
index 178cc96e..71d83928 100644
--- a/simgear/misc/ResourceManager.cxx
+++ b/simgear/misc/ResourceManager.cxx
@@ -20,11 +20,17 @@
 #include <simgear_config.h>
 
 #include <simgear/misc/ResourceManager.hxx>
+#include <simgear/debug/logstream.hxx>
 
 namespace simgear
 {
     
-static ResourceManager* static_manager = NULL;
+static ResourceManager* static_manager = nullptr;
+
+ResourceProvider::~ResourceProvider()
+{
+    // pin to this compilation unit
+}
 
 ResourceManager::ResourceManager()
 {
@@ -40,13 +46,20 @@ ResourceManager* ResourceManager::instance()
     return static_manager;
 }    
 
+ResourceManager::~ResourceManager()
+{
+    assert(this == static_manager);
+    static_manager = nullptr;
+    std::for_each(_providers.begin(), _providers.end(), 
+        [](ResourceProvider* p) { delete p; });
+}
 /**
  * trivial provider using a fixed base path
  */
 class BasePathProvider : public ResourceProvider
 {
 public:
-    BasePathProvider(const SGPath& aBase, int aPriority) :
+    BasePathProvider(const SGPath& aBase, ResourceManager::Priority aPriority) :
         ResourceProvider(aPriority),
         _base(aBase)
     {
@@ -69,6 +82,8 @@ void ResourceManager::addBasePath(const SGPath& aPath, Priority aPriority)
 
 void ResourceManager::addProvider(ResourceProvider* aProvider)
 {
+    assert(aProvider);
+
     ProviderVec::iterator it = _providers.begin();
     for (; it != _providers.end(); ++it) {
       if (aProvider->priority() > (*it)->priority()) {
@@ -81,6 +96,16 @@ void ResourceManager::addProvider(ResourceProvider* aProvider)
     _providers.push_back(aProvider);
 }
 
+void ResourceManager::removeProvider(ResourceProvider* aProvider)
+{
+    assert(aProvider);
+    auto it = std::find(_providers.begin(), _providers.end(), aProvider);
+    if (it == _providers.end()) {
+        SG_LOG(SG_GENERAL, SG_DEV_ALERT, "unknown provider doing remove");
+        return;
+    }
+}
+
 SGPath ResourceManager::findPath(const std::string& aResource, SGPath aContext)
 {
     if (!aContext.isNull()) {
@@ -90,9 +115,8 @@ SGPath ResourceManager::findPath(const std::string& aResource, SGPath aContext)
         }
     }
     
-    ProviderVec::iterator it = _providers.begin();
-    for (; it != _providers.end(); ++it) {
-      SGPath path = (*it)->resolve(aResource, aContext);
+    for (auto provider : _providers) {
+      SGPath path = provider->resolve(aResource, aContext);
       if (!path.isNull()) {
         return path;
       }
diff --git a/simgear/misc/ResourceManager.hxx b/simgear/misc/ResourceManager.hxx
index bfaa5310..a15aaf15 100644
--- a/simgear/misc/ResourceManager.hxx
+++ b/simgear/misc/ResourceManager.hxx
@@ -36,6 +36,8 @@ class ResourceProvider;
 class ResourceManager
 {
 public:
+    ~ResourceManager();
+
     typedef enum {
       PRIORITY_DEFAULT = 0,
       PRIORITY_FALLBACK = -100,
@@ -55,6 +57,8 @@ public:
      */
     void addProvider(ResourceProvider* aProvider);
     
+    void removeProvider(ResourceProvider* aProvider);
+
     /**
      * given a resource name (or path), find the appropriate real resource
      * path.
@@ -75,17 +79,19 @@ class ResourceProvider
 public:
     virtual SGPath resolve(const std::string& aResource, SGPath& aContext) const = 0;
     
-    virtual int priority() const
+    virtual ~ResourceProvider();
+
+    virtual ResourceManager::Priority priority() const
     {
       return _priority;
     }
     
 protected:
-    ResourceProvider(int aPriority) :
+    ResourceProvider(ResourceManager::Priority aPriority) :
       _priority(aPriority)
     {}
     
-    int _priority;
+    ResourceManager::Priority _priority = ResourceManager::PRIORITY_DEFAULT;
 };
     
 } // of simgear namespace