auto import from //depot/cupcake/@135843
diff --git a/linker/debugger.c b/linker/debugger.c
new file mode 100644
index 0000000..5bb065c
--- /dev/null
+++ b/linker/debugger.c
@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <ctype.h>
+#include <signal.h>
+#include <sys/mman.h>
+
+#include "linker.h"
+
+#include <sys/socket.h>
+#include <cutils/sockets.h>
+
+void notify_gdb_of_libraries();
+
+void debugger_signal_handler(int n)
+{
+    unsigned tid;
+    int s;
+
+    /* avoid picking up GC interrupts */
+    signal(SIGUSR1, SIG_IGN);
+
+    tid = gettid();
+    s = socket_local_client("android:debuggerd",
+            ANDROID_SOCKET_NAMESPACE_ABSTRACT, SOCK_STREAM);
+
+    if(s >= 0) {
+        /* debugger knows our pid from the credentials on the
+         * local socket but we need to tell it our tid.  It
+         * is paranoid and will verify that we are giving a tid
+         * that's actually in our process
+         */
+        write(s, &tid, sizeof(unsigned));
+
+        read(s, &tid, 1);
+        notify_gdb_of_libraries();
+        close(s);
+    }
+
+    /* remove our net so we fault for real when we return */
+    signal(n, SIG_IGN);
+}
+
+void debugger_init()
+{
+    signal(SIGILL, debugger_signal_handler);
+    signal(SIGABRT, debugger_signal_handler);
+    signal(SIGBUS, debugger_signal_handler);
+    signal(SIGFPE, debugger_signal_handler);
+    signal(SIGSEGV, debugger_signal_handler);
+    signal(SIGSTKFLT, debugger_signal_handler);
+    signal(SIGPIPE, debugger_signal_handler);
+}