Fixed failure copying reference when multiple process accessing.

kekyo · May 8, 2024 · caa490e · caa490e
1 parent aeab549
commit caa490e
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Showing 2 changed files with 54 additions and 2 deletions.
diff --git a/chibild/chibild.core/CilLinker.cs b/chibild/chibild.core/CilLinker.cs
@@ -507,7 +507,7 @@ injectToAssemblyPath is { } injectPath ?
                         Path.GetFileName(module.FileName));
                     if (tp != module.FileName)
                     {
-                        File.Copy(
+                        Utilities.SafeCopy(
                             module.FileName,
                             tp);
 
@@ -524,7 +524,7 @@ injectToAssemblyPath is { } injectPath ?
                                 Path.GetFileNameWithoutExtension(module.FileName) + ext);
                             if (File.Exists(fp) && fp != tp)
                             {
-                                File.Copy(fp, tp);
+                                Utilities.SafeCopy(fp, tp);
 
                                 this.logger.Information(
                                     $"Copied: {Path.GetFileName(fp)}");

diff --git a/chibild/chibild.core/Internal/Utilities.cs b/chibild/chibild.core/Internal/Utilities.cs
@@ -143,4 +143,56 @@ public static bool UpdateBytes(
         }
         return false;
     }
+
+    public static void SafeCopy(string from, string to)
+    {
+        // Note that although named 'Safe',
+        // atomic replacement of files is not realized.
+
+        var to1 = Guid.NewGuid().ToString("N");
+        var to2 = Guid.NewGuid().ToString("N");
+
+        try
+        {
+            File.Copy(from, to1);
+        }
+        catch
+        {
+            File.Delete(to1);
+            throw;
+        }
+
+        var isExistTo = File.Exists(to);
+        if (isExistTo)
+        {
+            try
+            {
+                File.Move(to, to2);
+            }
+            catch
+            {
+                File.Delete(to1);
+                throw;
+            }
+        }
+
+        try
+        {
+            File.Move(to1, to);
+        }
+        catch
+        {
+            File.Delete(to1);
+            if (isExistTo)
+            {
+                File.Move(to2, to);
+            }
+            throw;
+        }
+
+        if (isExistTo)
+        {
+            File.Delete(to2);
+        }
+    }
 }