Fix: dispatching any action causes actmon/actlog to crash with SIGSEGV

[merlea]

• Rename Svr -> Srv
• Always use 2 arguments for callback_done signature

A possible fix for #2829 basically setting all the job_done, action_done callbacks to have a signature void (*ast)(void *astprm, char *msg) and setting msg to NULL when applicable. Using this fix with the case described in #2829 leads to no error.

[zack-vii]

I think we need to add a test maybe using actlog (terminal version of actmon).
What i found is that actmon/actlog dont handle null either .. further they need to be protected in case the action monitor server (mdsip) becomes offline otherwise it may generate a stack overflow.

[zack-vii]

If the ACTION_MONITOR server becomes unreachabel/offline The CheckIN will eventually call MessageAst with a NULL for message. This will cause if (!parseMsg(reply, event)) to skip and call CheckIN recursively until the program stack overflows.

We need to be able to detect this from the callback msg somehow, possibly by returning a special message instead. alternatively the CheckIN must be called from a async outside of MessageAst with some wait time to prevent a runaway process at 100% as well as the stack overflow due to recursion.

[merlea]

OK. I removed the recursive calls to CheckIn since it already had a loop with pauses.

I also put some stubs for tests of actlog based on the original issue. We could compare the output of actlog with the expected one. I am not too familiar with the tests setup so let me know how best to integrate this.

[joshStillerman]

retest this please

[WhoBrokeTheBuild]

By changing the definition of the ast parameter to include arguments, you've triggered some compile errors. You can run a build/test with:

./deploy/build.sh --os=bootstrap
./deploy/build.sh --os=ubuntu24 --test

And here is the error from the Jenkins build:

gcc -Wall -Wextra -Werror   -g -DWITH_DEBUG_SYMBOLS -O0 -fvisibility=hidden  -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -fpic -shared-libgcc -fsigned-char -fno-strict-aliasing   -DLIBPREFIX=MDSplus -pthread -I/workspace/tests/64/_include -I/opt/jenkins/workspace/MDSplus_PR-2835/debian10-64/_include -I/workspace/tests/64/include -I/opt/jenkins/workspace/MDSplus_PR-2835/debian10-64/include  -m64 -c -o tcl_dispatch.o /opt/jenkins/workspace/MDSplus_PR-2835/debian10-64/tcl/tcl_dispatch.c

/opt/jenkins/workspace/MDSplus_PR-2835/debian10-64/tcl/tcl_dispatch.c: In function 'TclDispatch_command':

/opt/jenkins/workspace/MDSplus_PR-2835/debian10-64/tcl/tcl_dispatch.c:510:36: error: passing argument 5 of 'ServerDispatchCommand' from incompatible pointer type [-Werror=incompatible-pointer-types]

                                    CommandDone, c.cmd, iostatusp, NULL, 0);

                                    ^~~~~~~~~~~

In file included from /opt/jenkins/workspace/MDSplus_PR-2835/debian10-64/tcl/tcl_dispatch.c:35:

/opt/jenkins/workspace/MDSplus_PR-2835/debian10-64/include/servershr.h:41:63: note: expected 'void (*)(void *, char *)' but argument is of type 'void (*)(DispatchedCommand *, char *)' {aka 'void (*)(struct <anonymous> *, char *)'}

                                         char *command, void (*ast)(void *, char *),

                                                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~

If you include a fix for that, we will rerun the Jenkins build. Otherwise, we will look into this when we have time.

Thank you for investigating this so thoroughly, we greatly appreciate your help :)