incidentd can now handle multiple callers asking it for incident reports

Test: bit incident_test:* GtsIncidentManagerTestCases:*
Bug: 123543706
Change-Id: I9f671dd5d8b2ad139f952a23e575c2be16120459
diff --git a/cmds/incidentd/src/proto_util.cpp b/cmds/incidentd/src/proto_util.cpp
new file mode 100644
index 0000000..be2f24f
--- /dev/null
+++ b/cmds/incidentd/src/proto_util.cpp
@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2017 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 "proto_util.h"
+
+#include <google/protobuf/io/zero_copy_stream_impl.h>
+
+#include <android/util/protobuf.h>
+#include <android/util/ProtoOutputStream.h>
+#include <android-base/file.h>
+
+namespace android {
+namespace os {
+namespace incidentd {
+
+using namespace android::base;
+using namespace android::util;
+using google::protobuf::io::FileOutputStream;
+
+// special section ids
+const int FIELD_ID_INCIDENT_HEADER = 1;
+
+status_t write_header_section(int fd, const vector<uint8_t>& buf) {
+    status_t err;
+    const size_t bufSize = buf.size();
+
+    if (buf.empty()) {
+        return NO_ERROR;
+    }
+
+    err = write_section_header(fd, FIELD_ID_INCIDENT_HEADER, bufSize);
+    if (err != NO_ERROR) {
+        return err;
+    }
+
+    err = WriteFully(fd, (uint8_t const*)buf.data(), bufSize);
+    if (err != NO_ERROR) {
+        return err;
+    }
+
+    return NO_ERROR;
+}
+
+status_t write_section_header(int fd, int sectionId, size_t size) {
+    uint8_t buf[20];
+    uint8_t* p = write_length_delimited_tag_header(buf, sectionId, size);
+    return WriteFully(fd, buf, p - buf) ? NO_ERROR : -errno;
+}
+
+status_t write_section(int fd, int sectionId, const MessageLite& message) {
+    status_t err;
+
+    err = write_section_header(fd, sectionId, message.ByteSize());
+    if (err != NO_ERROR) {
+        return err;
+    }
+
+    FileOutputStream stream(fd);
+    if (!message.SerializeToZeroCopyStream(&stream)) {
+        return stream.GetErrno();
+    } else {
+        return NO_ERROR;
+    }
+}
+
+
+
+}  // namespace incidentd
+}  // namespace os
+}  // namespace android
+