checkpoint

Alpm/ExtensionMethods.cs

@@ -0,0 +1,48 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Runtime.ConstrainedExecution;
+
+namespace Foodsoft.Alpm
+{
+    public static class ExtensionMethods
+    {
+        [PrePrepareMethod]
+        public static Package? FindSatisfier(this IEnumerable<Package> pkgList, string depString)
+        {
+            var refs = new Dictionary<IntPtr, Package?>(10);
+            var listPtr = IntPtr.Zero;
+            
+            RuntimeHelpers.PrepareConstrainedRegions();
+            try
+            {
+                foreach (var pkg in pkgList)
+                {
+                    var release = false;
+                    var handle = pkg.Handle;
+                    var pkgPtr = handle.DangerousGetHandle();
+                    
+                    refs.Add(pkgPtr, null);
+                    handle.DangerousAddRef(ref release);
+                    if (!release) throw new ObjectDisposedException(handle.GetType().FullName);
+
+                    refs[pkgPtr] = pkg;
+                    listPtr = alpm.alpm_list_add(listPtr, handle.DangerousGetHandle());
+                }
+
+                var foundPtr = alpm.alpm_find_satisfier(listPtr, depString);
+                return foundPtr != IntPtr.Zero
+                    ? refs[foundPtr]
+                    : null;
+            }
+            finally
+            {
+                alpm.alpm_list_free(listPtr);
+                foreach (var pkg in refs.Values)
+                {
+                    pkg?.Handle.DangerousRelease();
+                }
+            }
+        }
+    }
+}