Wladimir J. van der Laan 9a2b5f22c1
Merge #18338: Fix wallet unload race condition
41b0baf43c243b64b394e774e336475a489cca2b gui: Handle WalletModel::unload asynchronous (João Barbosa)
ab31b9d6fe7b39713682e3f52d11238dbe042c16 Fix wallet unload race condition (Russell Yanofsky)

Pull request description:

  This PR consists in two fixes. The first fixes a concurrency issues with `boost::signals2`. The second fixes a wallet model destruction while it's being used.

  From boost signal documentation at https://www.boost.org/doc/libs/1_72_0/doc/html/signals2/thread-safety.html:

  > When a signal is invoked by calling signal::operator(), the invocation first acquires a lock on the signal's mutex. Then it obtains a handle to the signal's slot list and combiner. Next it releases the signal's mutex, before invoking the combiner to iterate through the slot list.

  This means that `UnregisterValidationInterface` doesn't prevent more calls to that interface. The fix consists in capturing the `shared_ptr<CValidationInterface>` in each internal slot.

  The GUI bug is fixed by using a `Qt::QueuedConnection` in the `WalletModel::unload` connection.

ACKs for top commit:
  ryanofsky:
    Code review ACK 41b0baf43c243b64b394e774e336475a489cca2b. Only change is moving assert as suggested
  hebasto:
    ACK 41b0baf43c243b64b394e774e336475a489cca2b, tested on Linux Mint 19.3.

Tree-SHA512: 4f712d8de65bc1214411831250de5dc0a9fd505fb84da5baf9f2cc4d551bc3abffc061616f00afe43dba7525af2cd96c9b54aeead9383145e3b8801f25d85f50
2020-03-31 15:07:06 +02:00
..
2020-03-16 10:51:11 +01:00
2019-08-15 13:05:10 +02:00
2019-10-24 16:01:43 -04:00

This directory contains the BitcoinQT graphical user interface (GUI). It uses the cross-platform framework Qt.

The current precise version for Qt 5 is specified in qt.mk.

Compile and run

See build instructions (macOS, Windows, Unix, etc).

To run:

./src/qt/bitcoin-qt

Files and directories

forms

Contains Designer UI files. They are created with Qt Creator, but can be edited using any text editor.

locale

Contains translations. They are periodically updated. The process is described here.

res

Resources such as the icon.

test

Tests.

bitcoingui.(h/cpp)

Represents the main window of the Bitcoin UI.

*model.(h/cpp)

The model. When it has a corresponding controller, it generally inherits from QAbstractTableModel. Models that are used by controllers as helpers inherit from other Qt classes like QValidator.

ClientModel is used by the main application bitcoingui and several models like peertablemodel.

*page.(h/cpp)

A controller. :NAMEpage.cpp generally includes :NAMEmodel.h and forms/:NAME.page.ui with a similar :NAME.

*dialog.(h/cpp)

Various dialogs, e.g. to open a URL. Inherit from QDialog.

paymentserver.(h/cpp)

Used to process BIP21 payment URI requests. Also handles URI based application switching (e.g. when following a bitcoin:... link from a browser).

walletview.(h/cpp)

Represents the view to a single wallet.

Other .h/cpp files

  • UI elements like BitcoinAmountField, which inherit from QWidget.
  • bitcoinstrings.cpp: automatically generated
  • bitcoinunits.(h/cpp): BTC / mBTC / etc handling
  • callback.h
  • guiconstants.h: UI colors, app name, etc
  • guiutil.h: several helper functions
  • macdockiconhandler.(h/mm): macOS dock icon handler
  • macnotificationhandler.(h/mm): display notifications in macOS

Contribute

See CONTRIBUTING.md for general guidelines. Specifically for Qt:

Using Qt Creator as IDE

You can use Qt Creator as an IDE. This is especially useful if you want to change the UI layout.

Download and install the community edition of Qt Creator. Uncheck everything except Qt Creator during the installation process.

Instructions for macOS:

  1. Make sure you installed everything through Homebrew mentioned in the macOS build instructions
  2. Use ./configure with the --enable-debug flag
  3. In Qt Creator do "New Project" -> Import Project -> Import Existing Project
  4. Enter "bitcoin-qt" as project name, enter src/qt as location
  5. Leave the file selection as it is
  6. Confirm the "summary page"
  7. In the "Projects" tab select "Manage Kits..."
  8. Select the default "Desktop" kit and select "Clang (x86 64bit in /usr/bin)" as compiler
  9. Select LLDB as debugger (you might need to set the path to your installation)
  10. Start debugging with Qt Creator (you might need to the executable to "bitcoin-qt" under "Run", which is where you can also add command line arguments)