RDKEMW-7226: Add Logs to calculate time for shutdown sequence

[yogeswaransky]

No description provided.

[Copilot]

Pull request overview

This PR adds logging and timing measurements for the telemetry2_0 shutdown sequence to help diagnose shutdown performance issues. The changes instrument both the systemd service shutdown process and the internal C application termination to capture timing information.

Changes:

• Added shutdown timing logs in systemd service file (ExecStop/ExecStopPost) that measure the time from stop initiation to completion
• Added shutdown timing logs in C code (terminate function) that measure internal cleanup duration
• Introduced timestamp-based duration calculation using temporary file for systemd-level timing

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
telemetry2_0.service	Added ExecStop and ExecStopPost commands that log shutdown initiation and completion with elapsed time calculation
source/telemetry2_0.c	Added timing instrumentation in terminate() function to log shutdown start, end, and duration in milliseconds

Comments suppressed due to low confidence (1)

source/telemetry2_0.c:112

• The variable name t2 is less descriptive than t_start. Consider renaming t2 to t_end for improved code readability and consistency.

    struct timespec t2, t_start;

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[Copilot]

The time calculation could produce incorrect results if the nanosecond subtraction (t2.tv_nsec - t_start.tv_nsec) is negative. When t2.tv_nsec is less than t_start.tv_nsec, the division will produce a negative millisecond value. The codebase already has a getLapsedTime function in source/scheduler/scheduler.c that properly handles nanosecond wraparound. Consider using that function instead of performing the calculation inline.

Suggested change

	T2Info("=== [SHUTDOWN] telemetry2_0 shutdown complete, total=%ldms ===\n",
	(t2.tv_sec - t_start.tv_sec) * 1000 + (t2.tv_nsec - t_start.tv_nsec) / 1000000);
	long sec = t2.tv_sec - t_start.tv_sec;
	long nsec = t2.tv_nsec - t_start.tv_nsec;
	if (nsec < 0)
	{
	sec -= 1;
	nsec += 1000000000L;
	}
	long elapsed_ms = sec * 1000L + nsec / 1000000L;
	T2Info("=== [SHUTDOWN] telemetry2_0 shutdown complete, total=%ldms ===\n",
	elapsed_ms);

[Copilot]

The ExecStopPost shell command evaluates data read from /tmp/.t2_stop_start inside an arithmetic expansion ELAPSED=$((T_END - ${T_START:-$T_END})) without any validation or sanitization. Since /tmp is world-writable, a local attacker can repeatedly overwrite /tmp/.t2_stop_start with a payload like $(malicious_command) and eventually win the race, causing that command substitution to execute as the service user (likely root) when the arithmetic expansion is evaluated. To fix this, treat /tmp/.t2_stop_start as untrusted input: either move it to a non-world-writable location with safe permissions or strictly validate that T_START is numeric before using it in arithmetic expansion so that no command substitution or non-numeric content can be interpreted.

Suggested change

ExecStopPost=/bin/sh -c 'T_START=$(cat /tmp/.t2_stop_start 2>/dev/null); T_END=$(date +%%s); ELAPSED=$((T_END - ${T_START:-$T_END})); echo "[SHUTDOWN] $(date +%%Y-%%m-%%dT%%H:%%M:%%S) telemetry2_0 stop completed in ${ELAPSED}s" >> /rdklogs/logs/telemetry2_0.txt.0 2>&1; rm -f /tmp/.t2_stop_start; /bin/rm -rf /tmp/.t2ReadyToReceiveEvents /tmp/telemetry_initialized_bootup /tmp/.t2ConfigReady'

ExecStopPost=/bin/sh -c 'T_START=$(cat /tmp/.t2_stop_start 2>/dev/null); T_END=$(date +%%s); case "$T_START" in ""|*[!0-9]*) T_START=$T_END;; esac; ELAPSED=$((T_END - T_START)); echo "[SHUTDOWN] $(date +%%Y-%%m-%%dT%%H:%%M:%%S) telemetry2_0 stop completed in ${ELAPSED}s" >> /rdklogs/logs/telemetry2_0.txt.0 2>&1; rm -f /tmp/.t2_stop_start; /bin/rm -rf /tmp/.t2ReadyToReceiveEvents /tmp/telemetry_initialized_bootup /tmp/.t2ConfigReady'

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

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[Copilot]

This file uses struct timespec, CLOCK_MONOTONIC, and clock_gettime() but does not include <time.h> directly. It may compile only due to indirect includes, which is not portable/reliable; please add the explicit header include for these time APIs.

[Copilot]

Both clock_gettime() calls ignore the return value. If either fails, the elapsed-time log can be garbage due to uninitialized timespec fields. Please handle failures (e.g., log an error and skip/zero the duration) to keep shutdown logging reliable.