Missing RAS COMMANDLINE, environment variables in core from mac

[pshipton]

Looking at a core file produced on AArch64 mac, running !coreinfo shows the following information is not available:

COMMANDLINE
COMMANDLINE is not available

Environment variables are not available

#15251 (comment)

@knn-k @keithc-ca

[knn-k]

This is not specific to AArch64. Intel macOS does not implement the feature, either.

openj9/debugtools/DDR_VM/src/com/ibm/j9ddr/corereaders/macho/MachoDumpReader.java

Lines 340 to 343 in aea459a

	public String getCommandLine() throws DataUnavailableException
	{
	throw new DataUnavailableException("No command line available on OSX");
	}

[pshipton]

We added command line capture into an environment variable so we should be able to implement it.
#14536

[knn-k]

The macOS build seems to capture only the command instead of the full command line. See an example below:

Test program:

public class GetCommandLine {
	public static void main(String[] args) {
		System.out.println("commandLine = [" + System.getenv("OPENJ9_JAVA_COMMAND_LINE") + "]");
	}
}

Running it on macOS:

% jdk-11.0.16.1+1/Contents/Home/bin/java -cp ~/Documents/java GetCommandLine
commandLine = [jdk-11.0.16.1+1/Contents/Home/bin/java]

It does not show the arguments -cp ~/Documents/java GetCommandLine.
Do I misunderstand anything?

[knn-k]

I opened PR #16104 to fix captureCommandLine() on macOS for the problem I found above.
The original code in #14536 was using the variable start correctly, but #14684 changed it to buffer.
FYI. @keithc-ca

[knn-k]

The problem here is how to put the information of environment variables in the core files for macOS (Intel/AArch64) in the Mach-O format.
I have little knowledge for that.