test-setup.sh: Attempt to raise the original signal once more (#18932)

On POSIX-like systems, processes may either terminate normally with an integer exit code. The exit code may span the full range of int, even though all but the waitid() function retur the bottom eight bits. In addition to that, processes may terminate abnormally due to a signal (SIGABRT, SIGSEGV, etc.)

POSIX shells (sh, bash, etc.) are more restrictive, in that they can only return exit codes between 0 and 126. 127 is used to denote that the executable cannot be found. Exit codes above 128 indicate that the process terminated due to a signal.

Right now we let test-setup.sh terminate using the exit code obtained using $?. This means that if a program terminates due to SIGABRT, test-setup.sh terminates with exit code 128+6=134. This causes us to lose some information, as the (remote) execution environment now only sees plain exit codes.

This change extends test-setup.sh to check for exit codes above 128. In that case it will send a signal to itself, so that the original signal condition is raised once again.

See also: bazelbuild/remote-apis#240

Closes #18827.

PiperOrigin-RevId: 547773406
Change-Id: Ia29a6ea1eefdb8caa5624a799755b420a61478a0

Co-authored-by: Ed Schouten <eschouten@apple.com>

tools/test/test-setup.sh

@@ -432,4 +432,8 @@ if [[ -n "$TEST_UNDECLARED_OUTPUTS_ZIP" ]] && cd "$TEST_UNDECLARED_OUTPUTS_DIR";
   fi
 fi
 
+# Raise the original signal if the test terminated abnormally.
+if [ $exitCode -gt 128 ]; then
+  kill -$(($exitCode - 128)) $$ &> /dev/null
+fi
 exit $exitCode