Merge bitcoin/bitcoin#28051: Get rid of shutdown.cpp/shutdown.h, use SignalInterrupt directly

6db04be102807ee0120981a9b8de62a55439dabb Get rid of shutdown.cpp/shutdown.h, use SignalInterrupt directly (Ryan Ofsky)
213542b625a6a4885fcbdfe236629a5f381eeb05 refactor: Add InitContext function to initialize NodeContext with global pointers (Ryan Ofsky)
feeb7b816affa790e02e7ba0780c4ef33d2310ff refactor: Remove calls to StartShutdown from KernelNotifications (Ryan Ofsky)
6824eecaf1e74624cf149ed20abd9145c49d614a refactor: Remove call to StartShutdown from stop RPC (Ryan Ofsky)
1d92d89edbb1812dc353084c62772ebb1024d632 util: Get rid of uncaught exceptions thrown by SignalInterrupt class (Ryan Ofsky)
ba93966368d3aaa426b97837ef475ec5aa612f5f refactor: Remove call to ShutdownRequested from IndexWaitSynced (Ryan Ofsky)
42e5829d9710ebebda5de356fab01dd7c149d5fa refactor: Remove call to ShutdownRequested from HTTPRequest (Ryan Ofsky)
73133c36aa9cc09546eabac18d0ea35274dd5d72 refactor: Add NodeContext::shutdown member (Ryan Ofsky)
f4a8bd6e2f03e786a84dd7763d1c04665e6371f2 refactor: Remove call to StartShutdown from qt (Ryan Ofsky)
f0c73c1336bee74fe2d58474ac36bca28c219e85 refactor: Remove call to ShutdownRequested from rpc/mining (Ryan Ofsky)
263b23f0082c60516acced1b03abb8e4d8f9ee46 refactor: Remove call to ShutdownRequested from chainstate init (Ryan Ofsky)

Pull request description:

  This change drops `shutdown.h` and `shutdown.cpp` files, replacing them with a `NodeContext::shutdown` member which is used to trigger shutdowns directly. This gets rid of an unnecessary layer of indirection, and allows getting rid of the `kernel::g_context` global.

  Additionally, this PR tries to improve error handling of `SignalInterrupt` code by marking relevant methods `[[nodiscard]]` to avoid the possibility of uncaught exceptions mentioned https://github.com/bitcoin/bitcoin/pull/27861#discussion_r1255496707.

  Behavior is changing In a few cases which are noted in individual commit messages. Particularly: GUI code more consistently interrupts RPCs when it is shutting down, shutdown state no longer persists between unit tests, the stop RPC now returns an RPC error if requesting shutdown fails instead of aborting, and other failed shutdown calls now log errors instead of aborting.

  This PR is a net reduction in lines of code, but in some cases the explicit error handling and lack of global shutdown functions do make it more verbose. The verbosity can be seen as good thing if it discourages more code from directly triggering shutdowns, and instead encourages code to return errors or send notifications that could be translated into shutdowns. Probably a number of existing shutdown calls could just be replaced by better error handling.

ACKs for top commit:
  achow101:
    ACK 6db04be102807ee0120981a9b8de62a55439dabb
  TheCharlatan:
    Re-ACK 6db04be102807ee0120981a9b8de62a55439dabb
  maflcko:
    ACK 6db04be102807ee0120981a9b8de62a55439dabb 👗
  stickies-v:
    re-ACK 6db04be102807ee0120981a9b8de62a55439dabb

Tree-SHA512: 7a34cb69085f37e813c43bdaded1a0cbf6c53bd95fdde96f0cb45346127fc934604c43bccd3328231ca2f1faf712a7418d047ceabd22ef2dca3c32ebb659e634

0 files changed, 0 insertions, 0 deletions