Add <hardware/qemu_pipe.h> header.

This header is used to implement qemu pipes, a very fast way to exchange
messages between the guest and the emulator program. See implementation and
tests under development/tools/emulator/system/libqemu/

Change-Id: I8272435cb9bf6e2a96ac62b9a56cbc5930052682

diff --git a/include/hardware/qemu_pipe.h b/include/hardware/qemu_pipe.h
new file mode 100644 (file)
index 0000000..146fea7
--- /dev/null
+++ b/include/hardware/qemu_pipe.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef ANDROID_INCLUDE_HARDWARE_QEMU_PIPE_H
+#define ANDROID_INCLUDE_HARDWARE_QEMU_PIPE_H
+
+/* Try to open a new Qemu fast-pipe. This function returns a file descriptor
+ * that can be used to communicate with a named service managed by the
+ * emulator.
+ *
+ * This file descriptor can be used as a standard pipe/socket descriptor.
+ *
+ * 'pipeName' is the name of the emulator service you want to connect to.
+ * E.g. 'opengles' or 'camera'.
+ *
+ * On success, return a valid file descriptor
+ * Returns -1 on error, and errno gives the error code, e.g.:
+ *
+ *    EINVAL  -> unknown/unsupported pipeName
+ *    ENOSYS  -> fast pipes not available in this system.
+ *
+ * ENOSYS should never happen, except if you're trying to run within a
+ * misconfigured emulator.
+ *
+ * You should be able to open several pipes to the same pipe service,
+ * except for a few special cases (e.g. GSM modem), where EBUSY will be
+ * returned if more than one client tries to connect to it.
+ */
+extern int  qemu_pipe_open(const char*  pipeName);
+
+#endif /* ANDROID_INCLUDE_HARDWARE_QEMUD_PIPE_H */