logd: separate Chatty only vs generic LogBufferTests

Separate these tests such that future log buffer implementations can
be run against the generic tests.  Use a parameterized fixture to
allow testing any number of log buffers.

Test: these unit tests
Change-Id: I6d90838e8efa019b934d08da25cab0c2405b66cd
diff --git a/logd/LogBufferTest.h b/logd/LogBufferTest.h
new file mode 100644
index 0000000..feaa279
--- /dev/null
+++ b/logd/LogBufferTest.h
@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2020 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.
+ */
+
+#pragma once
+
+#include <string>
+#include <vector>
+
+#include <gtest/gtest.h>
+
+#include "ChattyLogBuffer.h"
+#include "LogReaderList.h"
+#include "LogStatistics.h"
+#include "LogTags.h"
+#include "LogWhiteBlackList.h"
+
+struct LogMessage {
+    logger_entry entry;
+    std::string message;
+    bool regex_compare = false;  // Only set for expected messages, when true 'message' should be
+                                 // interpretted as a regex.
+};
+
+// Compares the ordered list of expected and result, causing a test failure with appropriate
+// information on failure.
+void CompareLogMessages(const std::vector<LogMessage>& expected,
+                        const std::vector<LogMessage>& result);
+// Sets hdr_size and len parameters appropriately.
+void FixupMessages(std::vector<LogMessage>* messages);
+
+class TestWriter : public LogWriter {
+  public:
+    TestWriter(std::vector<LogMessage>* msgs, bool* released)
+        : LogWriter(0, true, true), msgs_(msgs), released_(released) {}
+    bool Write(const logger_entry& entry, const char* message) override {
+        msgs_->emplace_back(LogMessage{entry, std::string(message, entry.len), false});
+        return true;
+    }
+
+    void Release() {
+        if (released_) *released_ = true;
+    }
+
+    std::string name() const override { return "test_writer"; }
+
+  private:
+    std::vector<LogMessage>* msgs_;
+    bool* released_;
+};
+
+class LogBufferTest : public testing::TestWithParam<std::string> {
+  protected:
+    void SetUp() override {
+        if (GetParam() == "chatty") {
+            log_buffer_.reset(new ChattyLogBuffer(&reader_list_, &tags_, &prune_, &stats_));
+        } else {
+            FAIL() << "Unknown buffer type selected for test";
+        }
+    }
+
+    void LogMessages(const std::vector<LogMessage>& messages) {
+        for (auto& [entry, message, _] : messages) {
+            log_buffer_->Log(static_cast<log_id_t>(entry.lid), log_time(entry.sec, entry.nsec),
+                             entry.uid, entry.pid, entry.tid, message.c_str(), message.size());
+        }
+    }
+
+    LogReaderList reader_list_;
+    LogTags tags_;
+    PruneList prune_;
+    LogStatistics stats_{false};
+    std::unique_ptr<LogBuffer> log_buffer_;
+};