Thread Support

[GoogleCodeExporter]

EDB currently has no support for debugging multi-threaded applications. When
you attach to a process, it simple attaches to the primary thread.

[GoogleCodeExporter]

There should be changes in the underlying functions to allow plugins and even
the debugger to get the state of a specific thread.
This is needed for example when setting hardware breakpoints.

[GoogleCodeExporter]

What you suggest is actually implemented to a certain degree. Basically, the
debugging core has a concept of an "active" thread.

When you ask it to set/get the state, it will act upon the active thread. By
default, after any given event, this will be the thread which triggered the
event. However, plugins can choose to set it manually to another thread ID. So
for example, you could do the following:

State state;
edb::tid_t t = edb::v1::debugger_core->active_thread();
edb::v1::debugger_core->set_active_thread(1234);
edb::v1::debugger_core->get_state(state);     // get the state of thread 1234
state.eip = 0x41414141; 
edb::v1::debugger_core->set_state(state);
edb::v1::debugger_core->set_active_thread(t); // reset the active thread to what it was

that will set the EIP of thread 1234 to 0x41414141 without effecting the other
threads.

[eteran]

With the new API in place, it is now trivial to access and modify the state of individual threads. And a fix has been applied the hardware BP plugin to utilize it