regulators: Add getMessages method
Add getMessages method. It gets the journal messages that have the
specified field set to the specified value.
Tested:
* Get field "_PID" with value "1".
* Get field "_SYSTEMD_UNIT" with value "init.scope".
* Get a field that does not exist and return vector size is 0.
* max parameter is 0 and return all messages.
* max parameter is less than number of messages in journal
and return max number of messages.
* max parameter is more than number of messages in journal
and return all messages
Signed-off-by: Bob King <Bob_King@wistron.com>
Change-Id: I6a9410b5509b3044c1de103e71276e8e7c241fa6
diff --git a/phosphor-regulators/src/journal.cpp b/phosphor-regulators/src/journal.cpp
new file mode 100644
index 0000000..be94275
--- /dev/null
+++ b/phosphor-regulators/src/journal.cpp
@@ -0,0 +1,150 @@
+
+/**
+ * Copyright © 2020 IBM Corporation
+ *
+ * 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 "journal.hpp"
+
+#include <string.h>
+#include <time.h>
+
+#include <cstdint>
+#include <ctime>
+#include <stdexcept>
+
+using namespace phosphor::logging;
+
+namespace phosphor::power::regulators
+{
+
+class JournalCloser
+{
+ public:
+ JournalCloser() = delete;
+ JournalCloser(const JournalCloser&) = delete;
+ JournalCloser(JournalCloser&&) = delete;
+ JournalCloser& operator=(const JournalCloser&) = delete;
+ JournalCloser& operator=(JournalCloser&&) = delete;
+
+ JournalCloser(sd_journal* journal) : journal{journal}
+ {
+ }
+ ~JournalCloser()
+ {
+ sd_journal_close(journal);
+ }
+
+ private:
+ sd_journal* journal{nullptr};
+};
+
+std::string SystemdJournal::getFieldValue(sd_journal* journal,
+ const char* field) const
+{
+ const char* data{nullptr};
+ size_t length{0};
+
+ // Get field data
+ int rc = sd_journal_get_data(journal, field, (const void**)&data, &length);
+ if (rc < 0)
+ {
+ throw std::runtime_error{
+ std::string{"Failed to read journal entry field: "} +
+ strerror(-rc)};
+ }
+
+ // Get field value
+ size_t prefix{0};
+ const void* eq = memchr(data, '=', length);
+ if (eq)
+ {
+ prefix = (const char*)eq - data + 1;
+ }
+ else
+ {
+ prefix = 0;
+ }
+
+ std::string value{data + prefix, length - prefix};
+
+ return value;
+}
+
+std::vector<std::string>
+ SystemdJournal::getMessages(const std::string& field,
+ const std::string& fieldValue, unsigned int max)
+{
+ sd_journal* journal;
+ std::vector<std::string> messages;
+
+ int rc = sd_journal_open(&journal, SD_JOURNAL_LOCAL_ONLY);
+ if (rc < 0)
+ {
+ throw std::runtime_error{std::string{"Failed to open journal: "} +
+ strerror(-rc)};
+ }
+
+ JournalCloser closer{journal};
+
+ SD_JOURNAL_FOREACH_BACKWARDS(journal)
+ {
+ // Get input field
+ std::string value = getFieldValue(journal, field.c_str());
+
+ // Compare field value and read data
+ if (value == fieldValue)
+ {
+ // Get SYSLOG_IDENTIFIER field
+ std::string syslog = getFieldValue(journal, "SYSLOG_IDENTIFIER");
+
+ // Get _PID field
+ std::string pid = getFieldValue(journal, "_PID");
+
+ // Get MESSAGE field
+ std::string message = getFieldValue(journal, "MESSAGE");
+
+ // Get realtime
+ uint64_t usec{0};
+ rc = sd_journal_get_realtime_usec(journal, &usec);
+ if (rc < 0)
+ {
+ throw std::runtime_error{
+ std::string{"Failed to get journal entry timestamp: "} +
+ strerror(-rc)};
+ }
+
+ // Convert realtime microseconds to date format
+ char dateBuffer[80];
+ std::string date;
+ std::time_t timeInSecs = usec / 1000000;
+ strftime(dateBuffer, sizeof(dateBuffer), "%b %d %H:%M:%S",
+ std::localtime(&timeInSecs));
+ date = dateBuffer;
+
+ // Store value to messages
+ value = date + " " + syslog + "[" + pid + "]: " + message;
+ messages.insert(messages.begin(), value);
+ }
+ // Set the maximum number of messages
+ if ((max != 0) && (messages.size() >= max))
+ {
+ break;
+ }
+ }
+
+ return messages;
+}
+
+} // namespace phosphor::power::regulators
\ No newline at end of file
diff --git a/phosphor-regulators/src/journal.hpp b/phosphor-regulators/src/journal.hpp
index 47dc347..4499aa6 100644
--- a/phosphor-regulators/src/journal.hpp
+++ b/phosphor-regulators/src/journal.hpp
@@ -15,6 +15,8 @@
*/
#pragma once
+#include <systemd/sd-journal.h>
+
#include <phosphor-logging/log.hpp>
#include <string>
@@ -82,6 +84,21 @@
* @param messages messages to log
*/
virtual void logInfo(const std::vector<std::string>& messages) = 0;
+
+ /**
+ * Gets the journal messages that have the specified field set to the
+ * specified value.
+ *
+ * @param field journal field to use during search
+ * @param fieldValue expected field value
+ * @param max Maximum number of messages to return.
+ * Specify 0 to return all matching messages.
+ *
+ * @return matching messages from the journal
+ */
+ virtual std::vector<std::string> getMessages(const std::string& field,
+ const std::string& fieldValue,
+ unsigned int max = 0) = 0;
};
/**
@@ -100,6 +117,11 @@
SystemdJournal& operator=(SystemdJournal&&) = delete;
virtual ~SystemdJournal() = default;
+ /** @copydoc Journal::getMessages() */
+ virtual std::vector<std::string> getMessages(const std::string& field,
+ const std::string& fieldValue,
+ unsigned int max) override;
+
/** @copydoc Journal::logDebug(const std::string&) */
virtual void logDebug(const std::string& message) override
{
@@ -147,6 +169,16 @@
logInfo(message);
}
}
+
+ private:
+ /**
+ * Gets the data object associated with a specific field from the
+ * current journal entry and return the data as string.
+ *
+ * @param journal the current journal entry
+ * @param field journal field to use during search
+ */
+ std::string getFieldValue(sd_journal* journal, const char* field) const;
};
} // namespace phosphor::power::regulators
diff --git a/phosphor-regulators/src/meson.build b/phosphor-regulators/src/meson.build
index ed22808..b20e0bd 100644
--- a/phosphor-regulators/src/meson.build
+++ b/phosphor-regulators/src/meson.build
@@ -13,6 +13,7 @@
'exception_utils.cpp',
'ffdc_file.cpp',
'id_map.cpp',
+ 'journal.cpp',
'pmbus_utils.cpp',
'rail.cpp',
'sensor_monitoring.cpp',
diff --git a/phosphor-regulators/test/mock_journal.hpp b/phosphor-regulators/test/mock_journal.hpp
index d1ebe0b..fbb67a7 100644
--- a/phosphor-regulators/test/mock_journal.hpp
+++ b/phosphor-regulators/test/mock_journal.hpp
@@ -41,6 +41,10 @@
MockJournal& operator=(MockJournal&&) = delete;
virtual ~MockJournal() = default;
+ MOCK_METHOD(std::vector<std::string>, getMessages,
+ (const std::string& field, const std::string& fieldValue,
+ unsigned int max),
+ (override));
MOCK_METHOD(void, logDebug, (const std::string& message), (override));
MOCK_METHOD(void, logDebug, (const std::vector<std::string>& messages),
(override));