upload android base code part6

android/device/generic/goldfish-opengl/system/OpenglSystemCommon/ProcessPipe.cpp

@@ -0,0 +1,78 @@
+/*
+* Copyright (C) 2016 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.
+*/
+
+#include "renderControl_enc.h"
+#include "qemu_pipe.h"
+
+#include <cutils/log.h>
+#include <pthread.h>
+
+static int                sProcPipe = 0;
+static pthread_once_t     sProcPipeOnce = PTHREAD_ONCE_INIT;
+// sProcUID is a unique ID per process assigned by the host.
+// It is different from getpid().
+static uint64_t           sProcUID = 0;
+
+// processPipeInitOnce is used to generate a process unique ID (puid).
+// processPipeInitOnce will only be called at most once per process.
+// Use it with pthread_once for thread safety.
+// The host associates resources with process unique ID (puid) for memory cleanup.
+// It will fallback to the default path if the host does not support it.
+// Processes are identified by acquiring a per-process 64bit unique ID from the
+// host.
+static void processPipeInitOnce() {
+    sProcPipe = qemu_pipe_open("GLProcessPipe");
+    if (sProcPipe < 0) {
+        sProcPipe = 0;
+        ALOGW("Process pipe failed");
+        return;
+    }
+    // Send a confirmation int to the host
+    int32_t confirmInt = 100;
+    ssize_t stat = 0;
+    do {
+        stat = ::write(sProcPipe, (const char*)&confirmInt,
+                sizeof(confirmInt));
+    } while (stat < 0 && errno == EINTR);
+
+    if (stat != sizeof(confirmInt)) { // failed
+        close(sProcPipe);
+        sProcPipe = 0;
+        ALOGW("Process pipe failed");
+        return;
+    }
+
+    // Ask the host for per-process unique ID
+    do {
+        stat = ::read(sProcPipe, (char*)&sProcUID,
+                      sizeof(sProcUID));
+    } while (stat < 0 && errno == EINTR);
+
+    if (stat != sizeof(sProcUID)) {
+        close(sProcPipe);
+        sProcPipe = 0;
+        sProcUID = 0;
+        ALOGW("Process pipe failed");
+        return;
+    }
+}
+
+bool processPipeInit(renderControl_encoder_context_t *rcEnc) {
+    pthread_once(&sProcPipeOnce, processPipeInitOnce);
+    if (!sProcPipe) return false;
+    rcEnc->rcSetPuid(rcEnc, sProcUID);
+    return true;
+}