Allow open of read-only files

The retry-as-r/o code was expecting an IOException rather than an
UnauthorizedAccessException.  The CLI was mostly working, because
commands are specifically r/o or r/w and the initial open uses the
appropriate mode, but the GUI was failing.

This adds a read-only test to the CLI test suite.  It wouldn't
have failed before, because it's just detecting success/failure,
but it seems like a useful thing to exercise.

(Issue #9)

AppCommon/WorkTree.cs

@@ -310,7 +310,7 @@ public WorkTree(string hostPathName, DepthLimiter depthLimitFunc, bool asReadOnl
                     FileAccess access = asReadOnly ? FileAccess.Read : FileAccess.ReadWrite;
                     hostStream = new FileStream(hostPathName, FileMode.Open, access,
                         FileShare.Read);
-                } catch (IOException ex) {
+                } catch (UnauthorizedAccessException ex) {
                     // Retry with read-only access unless we did that the first time around.
                     if (asReadOnly) {
                         throw;

cp2/ExtArchive.cs

@@ -231,7 +231,7 @@ private static bool OpenComponents(List<string> components, bool isReadOnly,
             try {
                 hostStream = new FileStream(hostFileName, FileMode.Open,
                     isReadOnly ? FileAccess.Read : FileAccess.ReadWrite, FileShare.Read);
-            } catch (IOException ex) {
+            } catch (Exception ex) {
                 Console.Error.WriteLine("Unable to open '" + hostFileName + "': " + ex.Message);
                 return false;
             }

cp2/Tests/TestMisc.cs

@@ -35,6 +35,7 @@ public static void RunTest(ParamsBag parms) {
             parms.FromNAPS = true;
 
             TestCtrlNames(parms);
+            TestReadOnly(parms);
 
             // AppleWorks filename formatting has been disabled.
             //TestAppleWorksName(parms);
@@ -203,5 +204,40 @@ private static void TestAppleWorksName(ParamsBag parms) {
                 Environment.CurrentDirectory = oldCurrentDir;
             }
         }
+
+        private static void TestReadOnly(ParamsBag parms) {
+            // Grab a copy of a ProDOS disk image.
+            string proTestName = "simple-dir-test.po";
+            FileUtil.CopyFile(Path.Join(Controller.TEST_DATA, "prodos", proTestName),
+                Path.Join(Controller.TEST_TMP, proTestName));
+
+            string oldCurrentDir = Environment.CurrentDirectory;
+            try {
+                Environment.CurrentDirectory = Controller.TEST_TMP;
+
+                // Delete a file to make sure things are set up correctly.
+                if (!Delete.HandleDelete("rm",
+                        new string[] { proTestName, "FILES.ADD.WITH" }, parms)) {
+                    throw new Exception("Initial rm failed");
+                }
+
+                // Mark the disk read-only.
+                FileInfo finfo = new FileInfo(proTestName);
+                finfo.IsReadOnly = true;
+
+                // Try another deletion, should fail cleanly.
+                if (Delete.HandleDelete("rm",
+                        new string[] { proTestName, "FILES.ADD.WITH" }, parms)) {
+                    throw new Exception("Read-only rm succeeded");
+                }
+
+                // The read-only "list" operation should succeed.
+                if (!Catalog.HandleList("list", new string[] { proTestName }, parms)) {
+                    throw new Exception("Read-only list failed");
+                }
+            } finally {
+                Environment.CurrentDirectory = oldCurrentDir;
+            }
+        }
     }
 }

cp2_wpf/MainController.cs

@@ -496,7 +496,7 @@ private void DoOpenWorkFile(string pathName, bool asReadOnly) {
                 // File is fully parsed.  Generate the archive tree.
                 PopulateArchiveTree();
             } catch (Exception ex) {
-                // Expecting IOException and InvalidDataException.
+                // Expecting IOException, UnauthorizedAccessException, and InvalidDataException.
                 ShowFileError("Unable to open file: " + ex.Message);
                 return;
             } finally {
@@ -613,7 +613,7 @@ private void DoOpenPhysicalDrive(string deviceName, bool asReadOnly) {
                 // File is fully parsed.  Generate the archive tree.
                 PopulateArchiveTree();
             } catch (Exception ex) {
-                // Expecting IOException and InvalidDataException.
+                // Expecting IOException, UnauthorizedAccessException, and InvalidDataException.
                 ShowFileError("Unable to open file: " + ex.Message);
                 return;
             } finally {