logd: add a SerializedLogBuffer suitable for compression
Initial commit for a SerializedLogBuffer. The intention here is for
the serialized data to be compressed (currently using zlib) to allow
for substantially longer logs in the same memory footprint.
Test: unit tests
Change-Id: I2528e4e1ff1cf3bc91130173a107f371f04d911a
diff --git a/logd/SerializedLogChunkTest.cpp b/logd/SerializedLogChunkTest.cpp
new file mode 100644
index 0000000..6572503
--- /dev/null
+++ b/logd/SerializedLogChunkTest.cpp
@@ -0,0 +1,284 @@
+/*
+ * 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.
+ */
+
+#include "SerializedLogChunk.h"
+
+#include <limits>
+
+#include <android-base/stringprintf.h>
+#include <android/log.h>
+#include <gtest/gtest.h>
+
+using android::base::StringPrintf;
+
+TEST(SerializedLogChunk, smoke) {
+ size_t chunk_size = 10 * 4096;
+ auto chunk = SerializedLogChunk{chunk_size};
+ EXPECT_EQ(chunk_size, chunk.PruneSize());
+
+ static const char log_message[] = "log message";
+ size_t expected_total_len = sizeof(SerializedLogEntry) + sizeof(log_message);
+ ASSERT_TRUE(chunk.CanLog(expected_total_len));
+ EXPECT_TRUE(chunk.CanLog(chunk_size));
+ EXPECT_FALSE(chunk.CanLog(chunk_size + 1));
+
+ log_time time(CLOCK_REALTIME);
+ auto* entry = chunk.Log(1234, time, 0, 1, 2, log_message, sizeof(log_message));
+ ASSERT_NE(nullptr, entry);
+
+ EXPECT_EQ(1234U, entry->sequence());
+ EXPECT_EQ(time, entry->realtime());
+ EXPECT_EQ(0U, entry->uid());
+ EXPECT_EQ(1, entry->pid());
+ EXPECT_EQ(2, entry->tid());
+ EXPECT_EQ(sizeof(log_message), entry->msg_len());
+ EXPECT_STREQ(log_message, entry->msg());
+ EXPECT_EQ(expected_total_len, entry->total_len());
+
+ EXPECT_FALSE(chunk.CanLog(chunk_size));
+ EXPECT_EQ(static_cast<int>(expected_total_len), chunk.write_offset());
+ EXPECT_EQ(1234U, chunk.highest_sequence_number());
+}
+
+TEST(SerializedLogChunk, fill_log_exactly) {
+ static const char log_message[] = "this is a log message";
+ size_t individual_message_size = sizeof(SerializedLogEntry) + sizeof(log_message);
+ size_t chunk_size = individual_message_size * 3;
+ auto chunk = SerializedLogChunk{chunk_size};
+ EXPECT_EQ(chunk_size, chunk.PruneSize());
+
+ ASSERT_TRUE(chunk.CanLog(individual_message_size));
+ EXPECT_NE(nullptr, chunk.Log(1, log_time(), 1000, 1, 1, log_message, sizeof(log_message)));
+
+ ASSERT_TRUE(chunk.CanLog(individual_message_size));
+ EXPECT_NE(nullptr, chunk.Log(2, log_time(), 1000, 2, 1, log_message, sizeof(log_message)));
+
+ ASSERT_TRUE(chunk.CanLog(individual_message_size));
+ EXPECT_NE(nullptr, chunk.Log(3, log_time(), 1000, 3, 1, log_message, sizeof(log_message)));
+
+ EXPECT_FALSE(chunk.CanLog(1));
+}
+
+TEST(SerializedLogChunk, three_logs) {
+ size_t chunk_size = 10 * 4096;
+ auto chunk = SerializedLogChunk{chunk_size};
+
+ chunk.Log(2, log_time(0x1234, 0x5678), 0x111, 0x222, 0x333, "initial message",
+ strlen("initial message"));
+ chunk.Log(3, log_time(0x2345, 0x6789), 0x444, 0x555, 0x666, "second message",
+ strlen("second message"));
+ auto uint64_t_max = std::numeric_limits<uint64_t>::max();
+ auto uint32_t_max = std::numeric_limits<uint32_t>::max();
+ chunk.Log(uint64_t_max, log_time(uint32_t_max, uint32_t_max), uint32_t_max, uint32_t_max,
+ uint32_t_max, "last message", strlen("last message"));
+
+ static const char expected_buffer_data[] =
+ "\x11\x01\x00\x00\x22\x02\x00\x00\x33\x03\x00\x00" // UID PID TID
+ "\x02\x00\x00\x00\x00\x00\x00\x00" // Sequence
+ "\x34\x12\x00\x00\x78\x56\x00\x00" // Timestamp
+ "\x0F\x00initial message" // msg_len + message
+ "\x44\x04\x00\x00\x55\x05\x00\x00\x66\x06\x00\x00" // UID PID TID
+ "\x03\x00\x00\x00\x00\x00\x00\x00" // Sequence
+ "\x45\x23\x00\x00\x89\x67\x00\x00" // Timestamp
+ "\x0E\x00second message" // msg_len + message
+ "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF" // UID PID TID
+ "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF" // Sequence
+ "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF" // Timestamp
+ "\x0C\x00last message"; // msg_len + message
+
+ for (size_t i = 0; i < chunk_size; ++i) {
+ if (i < sizeof(expected_buffer_data)) {
+ EXPECT_EQ(static_cast<uint8_t>(expected_buffer_data[i]), chunk.data()[i])
+ << "position: " << i;
+ } else {
+ EXPECT_EQ(0, chunk.data()[i]) << "position: " << i;
+ }
+ }
+}
+
+// Check that the CHECK() in DecReaderRefCount() if the ref count goes bad is caught.
+TEST(SerializedLogChunk, catch_DecCompressedRef_CHECK) {
+ size_t chunk_size = 10 * 4096;
+ auto chunk = SerializedLogChunk{chunk_size};
+ EXPECT_DEATH({ chunk.DecReaderRefCount(true); }, "");
+ EXPECT_DEATH({ chunk.DecReaderRefCount(false); }, "");
+}
+
+// Check that the CHECK() in ClearUidLogs() if the ref count is greater than 0 is caught.
+TEST(SerializedLogChunk, catch_ClearUidLogs_CHECK) {
+ size_t chunk_size = 10 * 4096;
+ auto chunk = SerializedLogChunk{chunk_size};
+ chunk.IncReaderRefCount();
+ EXPECT_DEATH({ chunk.ClearUidLogs(1000, LOG_ID_MAIN, nullptr); }, "");
+ chunk.DecReaderRefCount(false);
+}
+
+class UidClearTest : public testing::TestWithParam<bool> {
+ protected:
+ template <typename Write, typename Check>
+ void Test(const Write& write, const Check& check, bool expected_result) {
+ write(chunk_);
+
+ bool finish_writing = GetParam();
+ if (finish_writing) {
+ chunk_.FinishWriting();
+ }
+ EXPECT_EQ(expected_result, chunk_.ClearUidLogs(kUidToClear, LOG_ID_MAIN, nullptr));
+ if (finish_writing) {
+ chunk_.IncReaderRefCount();
+ }
+
+ check(chunk_);
+
+ if (finish_writing) {
+ chunk_.DecReaderRefCount(false);
+ }
+ }
+
+ static constexpr size_t kChunkSize = 10 * 4096;
+ static constexpr uid_t kUidToClear = 1000;
+ static constexpr uid_t kOtherUid = 1234;
+
+ SerializedLogChunk chunk_{kChunkSize};
+};
+
+// Test that ClearUidLogs() is a no-op if there are no logs of that UID in the buffer.
+TEST_P(UidClearTest, no_logs_in_chunk) {
+ auto write = [](SerializedLogChunk&) {};
+ auto check = [](SerializedLogChunk&) {};
+
+ Test(write, check, true);
+}
+
+// Test that ClearUidLogs() is a no-op if there are no logs of that UID in the buffer.
+TEST_P(UidClearTest, no_logs_from_uid) {
+ static const char msg[] = "this is a log message";
+ auto write = [](SerializedLogChunk& chunk) {
+ chunk.Log(1, log_time(), kOtherUid, 1, 2, msg, sizeof(msg));
+ };
+
+ auto check = [](SerializedLogChunk& chunk) {
+ auto* entry = chunk.log_entry(0);
+ EXPECT_STREQ(msg, entry->msg());
+ };
+
+ Test(write, check, false);
+}
+
+// Test that ClearUidLogs() returns true if all logs in a given buffer correspond to the given UID.
+TEST_P(UidClearTest, all_single) {
+ static const char msg[] = "this is a log message";
+ auto write = [](SerializedLogChunk& chunk) {
+ chunk.Log(1, log_time(), kUidToClear, 1, 2, msg, sizeof(msg));
+ };
+ auto check = [](SerializedLogChunk&) {};
+
+ Test(write, check, true);
+}
+
+// Test that ClearUidLogs() returns true if all logs in a given buffer correspond to the given UID.
+TEST_P(UidClearTest, all_multiple) {
+ static const char msg[] = "this is a log message";
+ auto write = [](SerializedLogChunk& chunk) {
+ chunk.Log(2, log_time(), kUidToClear, 1, 2, msg, sizeof(msg));
+ chunk.Log(3, log_time(), kUidToClear, 1, 2, msg, sizeof(msg));
+ chunk.Log(4, log_time(), kUidToClear, 1, 2, msg, sizeof(msg));
+ };
+ auto check = [](SerializedLogChunk&) {};
+
+ Test(write, check, true);
+}
+
+static std::string MakePrintable(const uint8_t* in, size_t length) {
+ std::string result;
+ for (size_t i = 0; i < length; ++i) {
+ uint8_t c = in[i];
+ if (isprint(c)) {
+ result.push_back(c);
+ } else {
+ result.append(StringPrintf("\\%02x", static_cast<int>(c) & 0xFF));
+ }
+ }
+ return result;
+}
+
+// This test clears UID logs at the beginning and end of the buffer, as well as two back to back
+// logs in the interior.
+TEST_P(UidClearTest, clear_beginning_and_end) {
+ static const char msg1[] = "this is a log message";
+ static const char msg2[] = "non-cleared message";
+ static const char msg3[] = "back to back cleared messages";
+ static const char msg4[] = "second in a row gone";
+ static const char msg5[] = "but we save this one";
+ static const char msg6[] = "and this 1!";
+ static const char msg7[] = "the last one goes too";
+ auto write = [](SerializedLogChunk& chunk) {
+ ASSERT_NE(nullptr, chunk.Log(1, log_time(), kUidToClear, 1, 2, msg1, sizeof(msg1)));
+ ASSERT_NE(nullptr, chunk.Log(2, log_time(), kOtherUid, 1, 2, msg2, sizeof(msg2)));
+ ASSERT_NE(nullptr, chunk.Log(3, log_time(), kUidToClear, 1, 2, msg3, sizeof(msg3)));
+ ASSERT_NE(nullptr, chunk.Log(4, log_time(), kUidToClear, 1, 2, msg4, sizeof(msg4)));
+ ASSERT_NE(nullptr, chunk.Log(5, log_time(), kOtherUid, 1, 2, msg5, sizeof(msg5)));
+ ASSERT_NE(nullptr, chunk.Log(6, log_time(), kOtherUid, 1, 2, msg6, sizeof(msg6)));
+ ASSERT_NE(nullptr, chunk.Log(7, log_time(), kUidToClear, 1, 2, msg7, sizeof(msg7)));
+ };
+
+ auto check = [](SerializedLogChunk& chunk) {
+ size_t read_offset = 0;
+ auto* entry = chunk.log_entry(read_offset);
+ EXPECT_STREQ(msg2, entry->msg());
+ read_offset += entry->total_len();
+
+ entry = chunk.log_entry(read_offset);
+ EXPECT_STREQ(msg5, entry->msg());
+ read_offset += entry->total_len();
+
+ entry = chunk.log_entry(read_offset);
+ EXPECT_STREQ(msg6, entry->msg()) << MakePrintable(chunk.data(), chunk.write_offset());
+ read_offset += entry->total_len();
+
+ EXPECT_EQ(static_cast<int>(read_offset), chunk.write_offset());
+ };
+ Test(write, check, false);
+}
+
+// This tests the opposite case of beginning_and_end, in which we don't clear the beginning or end
+// logs. There is a single log pruned in the middle instead of back to back logs.
+TEST_P(UidClearTest, save_beginning_and_end) {
+ static const char msg1[] = "saved first message";
+ static const char msg2[] = "cleared interior message";
+ static const char msg3[] = "last message stays";
+ auto write = [](SerializedLogChunk& chunk) {
+ ASSERT_NE(nullptr, chunk.Log(1, log_time(), kOtherUid, 1, 2, msg1, sizeof(msg1)));
+ ASSERT_NE(nullptr, chunk.Log(2, log_time(), kUidToClear, 1, 2, msg2, sizeof(msg2)));
+ ASSERT_NE(nullptr, chunk.Log(3, log_time(), kOtherUid, 1, 2, msg3, sizeof(msg3)));
+ };
+
+ auto check = [](SerializedLogChunk& chunk) {
+ size_t read_offset = 0;
+ auto* entry = chunk.log_entry(read_offset);
+ EXPECT_STREQ(msg1, entry->msg());
+ read_offset += entry->total_len();
+
+ entry = chunk.log_entry(read_offset);
+ EXPECT_STREQ(msg3, entry->msg());
+ read_offset += entry->total_len();
+
+ EXPECT_EQ(static_cast<int>(read_offset), chunk.write_offset());
+ };
+ Test(write, check, false);
+}
+
+INSTANTIATE_TEST_CASE_P(UidClearTests, UidClearTest, testing::Values(true, false));