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2022-03-29 14:54:55 +01:00
parent 97776f12e0
commit 74977804b1
2 changed files with 29 additions and 7 deletions

View File

@@ -28,6 +28,10 @@ namespace Bloom::DebugServers::Gdb
Connection() = delete;
Connection(const Connection&) = delete;
Connection& operator = (Connection&) = delete;
/*
* TODO: Implement this. For now, use the move constructor.
*/
Connection& operator = (Connection&&) = delete;
Connection(Connection&& other) noexcept
@@ -69,16 +73,24 @@ namespace Bloom::DebugServers::Gdb
private:
std::optional<int> socketFileDescriptor;
EpollInstance epollInstance = EpollInstance();
struct sockaddr_in socketAddress = {};
int maxPacketSize = 1024;
/**
* The interruptEventNotifier allows us to interrupt blocking IO calls on the GDB debug server.
* Under the hood, this is just a wrapper for a Linux event notifier. See the EventNotifier class for more.
* The interruptEventNotifier (instance of EventNotifier) allows us to interrupt blocking I/O calls on this
* connection's socket. Under the hood, the EventNotifier class is just an RAII wrapper for a Linux eventfd
* object.
*
* The file descriptors of the eventfd object and the socket are both added to an EpollInstance (which is just
* an RAII wrapper for a Linux epoll instance). The EpollInstance object is then used to wait for events on
* either of the two file descriptors. See any of the Connection I/O functions (e.g Connection::read()) for
* more on this.
*
* See the EventNotifier and EpollInstance classes for more.
*/
EventNotifier& interruptEventNotifier;
EpollInstance epollInstance = EpollInstance();
bool readInterruptEnabled = false;
/**
@@ -132,8 +144,16 @@ namespace Bloom::DebugServers::Gdb
*/
void write(const std::vector<unsigned char>& buffer);
/**
* Removes this->interruptEventNotifier's file descriptor from the EpollInstance (this->epollInstance),
* preventing subsequent I/O operations on this->socketFileDescriptor from being interrupted.
*/
void disableReadInterrupts();
/**
* Inserts this->interruptEventNotifier's file descriptor into the EpollInstance (this->epollInstance),
* allowing for subsequent I/O operations on this->socketFileDescriptor to be interrupted.
*/
void enableReadInterrupts();
};
}

View File

@@ -89,12 +89,14 @@ namespace Bloom::DebugServers::Gdb
int serverSocketFileDescriptor = -1;
/**
* We don't listen on the this->serverSocketFileDescriptor directly. Instead, we use an EpollInstance to
* monitor both this->serverSocketFileDescriptor and this->interruptEventNotifier. This allows us to interrupt
* any blocking socket IO calls when EventNotifier::notify() is called on this->interruptEventNotifier.
* When waiting for a connection, we don't listen on the this->serverSocketFileDescriptor directly. Instead,
* we use an EpollInstance to monitor both this->serverSocketFileDescriptor and this->interruptEventNotifier.
* This allows us to interrupt any blocking socket IO calls when EventNotifier::notify() is called on
* this->interruptEventNotifier.
*
* See GdbRspDebugServer::init()
* See DebugServer::interruptEventNotifier
* See EpollInstance
* See EventNotifier
*/
EpollInstance epollInstance = EpollInstance();