9b009fae6e qa: Test concurrent wallet loading (João Barbosa)
b9971ae585 wallet: Handle concurrent wallet loading (João Barbosa)
Pull request description:
This PR handles concurrent wallet loading.
This can be tested by running in parallel the following script a couple of times:
```sh
for i in {1..10}
do
src/bitcoin-cli -regtest loadwallet foo
src/bitcoin-cli -regtest unloadwallet foo
done
```
Eventually the error occurs:
```
error code: -4
error message:
Wallet already being loading.
```
For reference, loading and already loaded wallet gives:
```
error code: -4
error message:
Wallet file verification failed. Error loading wallet w1. Duplicate -wallet filename specified.
```
Fixes#19232.
ACKs for top commit:
MarcoFalke:
Concept ACK 9b009fae6e I have not reviewed the code
hebasto:
ACK 9b009fae6e, tested on Linux Mint 20 (x86_64):
ryanofsky:
Code review good-but-not-ideal ACK 9b009fae6e
Tree-SHA512: 0ccd77b03c0926e4c4e51efb31e193b93cb4b9ffe8bac6bb018f7344c55dfd939b873b8cf5e657dca73e6202eb75aa672de2acb787cc133184b0b3b51e47b972
5c3c7cc50c