1 files changed, 73 insertions, 0 deletions
diff --git a/nsprpub/pr/tests/pushtop.c b/nsprpub/pr/tests/pushtop.c
new file mode 100644
index 0000000000..621a7c7248
--- /dev/null
+++ b/nsprpub/pr/tests/pushtop.c
@@ -0,0 +1,73 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* A regression test for bug 794316 */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "prio.h"
+
+static PRIOMethods dummyMethods;
+
+int main()
+{
+    PRDescIdentity topId, middleId, bottomId;
+    PRFileDesc *top, *middle, *bottom;
+    PRFileDesc *fd;
+
+    topId = PR_GetUniqueIdentity("top");
+    middleId = PR_GetUniqueIdentity("middle");
+    bottomId = PR_GetUniqueIdentity("bottom");
+
+    top = PR_CreateIOLayerStub(topId, &dummyMethods);
+    middle = PR_CreateIOLayerStub(middleId, &dummyMethods);
+    bottom = PR_CreateIOLayerStub(bottomId, &dummyMethods);
+
+    fd = bottom;
+    PR_PushIOLayer(fd, PR_TOP_IO_LAYER, middle);
+    PR_PushIOLayer(fd, PR_TOP_IO_LAYER, top);
+
+    top = fd;
+    middle = top->lower;
+    bottom = middle->lower;
+
+    /* Verify that the higher pointers are correct. */
+    if (middle->higher != top) {
+        fprintf(stderr, "middle->higher is wrong\n");
+        fprintf(stderr, "FAILED\n");
+        exit(1);
+    }
+    if (bottom->higher != middle) {
+        fprintf(stderr, "bottom->higher is wrong\n");
+        fprintf(stderr, "FAILED\n");
+        exit(1);
+    }
+
+    top = PR_PopIOLayer(fd, topId);
+    top->dtor(top);
+
+    middle = fd;
+    bottom = middle->lower;
+
+    /* Verify that the higher pointer is correct. */
+    if (bottom->higher != middle) {
+        fprintf(stderr, "bottom->higher is wrong\n");
+        fprintf(stderr, "FAILED\n");
+        exit(1);
+    }
+
+    middle = PR_PopIOLayer(fd, middleId);
+    middle->dtor(middle);
+    if (fd->identity != bottomId) {
+        fprintf(stderr, "The bottom layer has the wrong identity\n");
+        fprintf(stderr, "FAILED\n");
+        exit(1);
+    }
+    fd->dtor(fd);
+
+    printf("PASS\n");
+    return 0;
+}