3 files changed, 32 insertions, 14 deletions

diff --git a/launcher/minecraft/Library.cpp b/launcher/minecraft/Library.cpp
index 1689e27c..42a42d87 100644
--- a/launcher/minecraft/Library.cpp
+++ b/launcher/minecraft/Library.cpp
@@ -112,9 +112,9 @@ QList<NetAction::Ptr> Library::getDownloads(
     {
         if(isNative())
         {
-            if(m_nativeClassifiers.contains(runtimeContext.currentSystem()))
+            auto nativeClassifier = getCompatibleNative(runtimeContext);
+            if(!nativeClassifier.isNull())
             {
-                auto nativeClassifier = m_nativeClassifiers[runtimeContext.currentSystem()];
                 if(nativeClassifier.contains("${arch}"))
                 {
                     auto nat32Classifier = nativeClassifier;
@@ -215,7 +215,7 @@ bool Library::isActive(const RuntimeContext & runtimeContext) const
         RuleAction ruleResult = Disallow;
         for (auto rule : m_rules)
         {
-            RuleAction temp = rule->apply(this);
+            RuleAction temp = rule->apply(this, runtimeContext);
             if (temp != Defer)
                 ruleResult = temp;
         }
@@ -223,7 +223,7 @@ bool Library::isActive(const RuntimeContext & runtimeContext) const
     }
     if (isNative())
     {
-        result = result && m_nativeClassifiers.contains(runtimeContext.currentSystem());
+        result = result && !getCompatibleNative(runtimeContext).isNull();
     }
     return result;
 }
@@ -238,6 +238,19 @@ bool Library::isAlwaysStale() const
     return m_hint == "always-stale";
 }
 
+QString Library::getCompatibleNative(const RuntimeContext & runtimeContext) const {
+    // try to match precise classifier "[os]-[arch]"
+    auto entry = m_nativeClassifiers.constFind(runtimeContext.getClassifier());
+    // try to match imprecise classifier on legacy architectures "[os]"
+    if (entry == m_nativeClassifiers.constEnd() && runtimeContext.isLegacyArch())
+        entry = m_nativeClassifiers.constFind(runtimeContext.system);
+
+    if (entry == m_nativeClassifiers.constEnd())
+        return QString();
+
+    return entry.value();
+}
+
 void Library::setStoragePrefix(QString prefix)
 {
     m_storagePrefix = prefix;
@@ -271,9 +284,10 @@ QString Library::filename(const RuntimeContext & runtimeContext) const
 
     // otherwise native, override classifiers. Mojang HACK!
     GradleSpecifier nativeSpec = m_name;
-    if (m_nativeClassifiers.contains(runtimeContext.currentSystem()))
+    QString nativeClassifier = getCompatibleNative(runtimeContext);
+    if (!nativeClassifier.isNull())
     {
-        nativeSpec.setClassifier(m_nativeClassifiers[runtimeContext.currentSystem()]);
+        nativeSpec.setClassifier(nativeClassifier);
     }
     else
     {
@@ -299,9 +313,10 @@ QString Library::storageSuffix(const RuntimeContext & runtimeContext) const
 
     // otherwise native, override classifiers. Mojang HACK!
     GradleSpecifier nativeSpec = m_name;
-    if (m_nativeClassifiers.contains(runtimeContext.currentSystem()))
+    QString nativeClassifier = getCompatibleNative(runtimeContext);
+    if (!nativeClassifier.isNull())
     {
-        nativeSpec.setClassifier(m_nativeClassifiers[runtimeContext.currentSystem()]);
+        nativeSpec.setClassifier(nativeClassifier);
     }
     else
     {
diff --git a/launcher/minecraft/Library.h b/launcher/minecraft/Library.h
index e0432fb8..b8fae9ec 100644
--- a/launcher/minecraft/Library.h
+++ b/launcher/minecraft/Library.h
@@ -3,6 +3,7 @@
 #include <net/NetAction.h>
 #include <QPair>
 #include <QList>
+#include <QString>
 #include <QStringList>
 #include <QMap>
 #include <QDir>
@@ -155,6 +156,8 @@ public: /* methods */
     QList<NetAction::Ptr> getDownloads(const RuntimeContext & runtimeContext, class HttpMetaCache * cache,
                                      QStringList & failedLocalFiles, const QString & overridePath) const;
 
+    QString getCompatibleNative(const RuntimeContext & runtimeContext) const;
+
 private: /* methods */
     /// the default storage prefix used by PolyMC
     static QString defaultStoragePrefix();
diff --git a/launcher/minecraft/Rule.h b/launcher/minecraft/Rule.h
index 2ed49d78..4c75cee4 100644
--- a/launcher/minecraft/Rule.h
+++ b/launcher/minecraft/Rule.h
@@ -37,7 +37,7 @@ class Rule
 {
 protected:
     RuleAction m_result;
-    virtual bool applies(const Library *parent) = 0;
+    virtual bool applies(const Library *parent, const RuntimeContext & runtimeContext) = 0;
 
 public:
     Rule(RuleAction result) : m_result(result)
@@ -45,9 +45,9 @@ public:
     }
     virtual ~Rule() {};
     virtual QJsonObject toJson() = 0;
-    RuleAction apply(const Library *parent)
+    RuleAction apply(const Library *parent, const RuntimeContext & runtimeContext)
     {
-        if (applies(parent))
+        if (applies(parent, runtimeContext))
             return m_result;
         else
             return Defer;
@@ -63,9 +63,9 @@ private:
     QString m_version_regexp;
 
 protected:
-    virtual bool applies(const Library *)
+    virtual bool applies(const Library *, const RuntimeContext & runtimeContext)
     {
-        return (m_system == RuntimeContext::currentSystem());
+        return runtimeContext.classifierMatches(m_system);
     }
     OsRule(RuleAction result, QString system, QString version_regexp)
         : Rule(result), m_system(system), m_version_regexp(version_regexp)
@@ -84,7 +84,7 @@ public:
 class ImplicitRule : public Rule
 {
 protected:
-    virtual bool applies(const Library *)
+    virtual bool applies(const Library *, const RuntimeContext & runtimeContext)
     {
         return true;
     }