On Wed, 21 Feb 2024 21:13:36 GMT, Alex Menkov <amen...@openjdk.org> wrote:
> VirtualMachine.loadAgentPath/loadAgentLibrary can fail with > AgentLoadException in 2 cases: > - attach listener returns error; in the case the exception is thrown from > HotSpotVirtualMachine.processCompletionStatus (called from > HotSpotVirtualMachine.execute); > - attach listener returns success, but reply does not contain Agent_onAttach > return code ("return code: %d" message). > > before jdk21 if attach listener fails to load required library, it returned > error (case 1) > from jdk21 attach listener always returns success (case 2) > Both cases are ok, but for 2nd case HotSpotVirtualMachine.loadAgentLibrary > read only single line of the response message, so exception message didn't > contain error details. > > The fix updates HotSpotVirtualMachine.loadAgentLibrary to read the whole > response message. > Walking through the code, fixed some other minor things in attach listener > and attach API implementation (commented in the code) > > Testing: > - test/jdk/com/sun/tools; > - tier1,tier2,tier5-svc This pull request has now been integrated. Changeset: fc67c2b4 Author: Alex Menkov <amen...@openjdk.org> URL: https://git.openjdk.org/jdk/commit/fc67c2b4f17216d4adcc0825d0f378ae4f150025 Stats: 150 lines in 6 files changed: 109 ins; 16 del; 25 mod 8325530: Vague error message when com.sun.tools.attach.VirtualMachine fails to load agent library Reviewed-by: sspitsyn, cjplummer ------------- PR: https://git.openjdk.org/jdk/pull/17954