1 files changed, 106 insertions, 0 deletions
diff --git a/logd/LogReaderThread.h b/logd/LogReaderThread.h
new file mode 100644
index 0000000000..20624f2e44
--- /dev/null
+++ b/logd/LogReaderThread.h
@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2012-2013 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 <pthread.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <time.h>
+
+#include <chrono>
+#include <condition_variable>
+#include <list>
+#include <memory>
+
+#include <log/log.h>
+
+#include "LogBuffer.h"
+#include "LogWriter.h"
+
+class LogReaderList;
+
+class LogReaderThread {
+  public:
+    LogReaderThread(LogBuffer* log_buffer, LogReaderList* reader_list,
+                    std::unique_ptr<LogWriter> writer, bool non_block, unsigned long tail,
+                    LogMask log_mask, pid_t pid, log_time start_time, uint64_t sequence,
+                    std::chrono::steady_clock::time_point deadline);
+    void triggerReader_Locked() { thread_triggered_condition_.notify_all(); }
+
+    void triggerSkip_Locked(log_id_t id, unsigned int skip) { skip_ahead_[id] = skip; }
+    void cleanSkip_Locked();
+
+    void release_Locked() {
+        // gracefully shut down the socket.
+        writer_->Shutdown();
+        release_ = true;
+        thread_triggered_condition_.notify_all();
+    }
+
+    bool IsWatching(log_id_t id) const { return flush_to_state_->log_mask() & (1 << id); }
+    bool IsWatchingMultiple(LogMask log_mask) const {
+        return flush_to_state_->log_mask() & log_mask;
+    }
+
+    std::string name() const { return writer_->name(); }
+    uint64_t start() const { return flush_to_state_->start(); }
+    std::chrono::steady_clock::time_point deadline() const { return deadline_; }
+    FlushToState& flush_to_state() { return *flush_to_state_; }
+
+  private:
+    void ThreadFunction();
+    // flushTo filter callbacks
+    FilterResult FilterFirstPass(log_id_t log_id, pid_t pid, uint64_t sequence, log_time realtime);
+    FilterResult FilterSecondPass(log_id_t log_id, pid_t pid, uint64_t sequence, log_time realtime);
+
+    std::condition_variable thread_triggered_condition_;
+    LogBuffer* log_buffer_;
+    LogReaderList* reader_list_;
+    std::unique_ptr<LogWriter> writer_;
+
+    // Set to true to cause the thread to end and the LogReaderThread to delete itself.
+    bool release_ = false;
+
+    // If set to non-zero, only pids equal to this are read by the reader.
+    const pid_t pid_;
+    // When a reader is referencing (via start_) old elements in the log buffer, and the log
+    // buffer's size grows past its memory limit, the log buffer may request the reader to skip
+    // ahead a specified number of logs.
+    unsigned int skip_ahead_[LOG_ID_MAX];
+    // LogBuffer::FlushTo() needs to store state across subsequent calls.
+    std::unique_ptr<FlushToState> flush_to_state_;
+
+    // These next three variables are used for reading only the most recent lines aka `adb logcat
+    // -t` / `adb logcat -T`.
+    // tail_ is the number of most recent lines to print.
+    unsigned long tail_;
+    // count_ is the result of a first pass through the log buffer to determine how many total
+    // messages there are.
+    unsigned long count_;
+    // index_ is used along with count_ to only start sending lines once index_ > (count_ - tail_)
+    // and to disconnect the reader (if it is dumpAndClose, `adb logcat -t`), when index_ >= count_.
+    unsigned long index_;
+
+    // When a reader requests logs starting from a given timestamp, its stored here for the first
+    // pass, such that logs before this time stamp that are accumulated in the buffer are ignored.
+    log_time start_time_;
+    // CLOCK_MONOTONIC based deadline used for log wrapping.  If this deadline expires before logs
+    // wrap, then wake up and send the logs to the reader anyway.
+    std::chrono::steady_clock::time_point deadline_;
+    // If this reader is 'dumpAndClose' and will disconnect once it has read its intended logs.
+    const bool non_block_;
+};