9bac71350d98580cc7441957fc7c3fa2f4158553 build: make HAVE_O_CLOEXEC available outside LevelDB (bugfix) (Sebastian Falbesoner)
584fd91d2d294883e6896dbd64a2176528e94581 init: only use pipe2 if availabile, check in configure (Sebastian Falbesoner)
Pull request description:
The result of the O_CLOEXEC availability check is currently only set in the Makefile and passed to LevelDB (see `LEVELDB_CPPFLAGS_INT` in `src/Makefile.leveldb.include`), but not defined to be used in our codebase. This means that code within the preprocessor conditional `#if HAVE_O_CLOEXEC` was actually never compiled. On the master branch this is currently used for pipe creation in `src/shutdown.cpp`, PR #21007 moves this part to a new module (I found the issue while testing that PR).
The fix is similar to the one in #19803, which solved the same problem for HAVE_FDATASYNC.
In the course of working on the PR it turned out that pipe2 is not available an all platforms, hence a configure check and a corresponding define HAVE_PIPE2 is introduced and used.
The PR can be tested by anyone with a system that has pipe2 and O_CLOEXEC available by putting gibberish into the HAVE_O_CLOEXEC block: on master, everything should compile fine, on PR, the compiler should abort with an error. At least that's my naive way of testing preprocessor logic, happy to hear more sophisticated ways :-)
ACKs for top commit:
laanwj:
Code review ACK 9bac71350d98580cc7441957fc7c3fa2f4158553
Tree-SHA512: aec89faf6ba52b6f014c610ebef7b725d9e967207d58b42a4a71afc9f1268fcb673ecc85b33a2a3debba8105a304dd7edaba4208c5373fcef2ab83e48a170051
1fabd59e7 Break circular dependency: init -> * -> init by extracting shutdown.h (Ben Woosley)
e62fdfeea Drop unused init.h includes (Ben Woosley)
Pull request description:
Most includers just wanted to react to pending shutdown.
This isolates access to `fRequestShutdown` and limits access to the shutdown api functions, including the new `CancelShutdown` for setting it to `false`.
Tree-SHA512: df42f75dfbba163576710e9a67cf1228531fd99d70a2f187bfba0bcc476d6749cf88180a97e66a81bb5b6c3c7f0917de7402d26039ba7b644cb7509b02f7e267
