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Right, I see the use in this now. How difficult would it be to wrap this up in a reusable script that you could run directly, instead of having to manually work
by robbles 14y ago
Right, I see the use in this now. How difficult would it be to wrap this up in a reusable script that you could run directly, instead of having to manually work through the debugger prompt?
- ebroder 14y agoHmm, it'd probably be doable. In particular, you can use the "commands" command to script what happens when you hit a breakpoint (a friend talked about this in a Ksplice GDB blog post: https://blogs.oracle.com/ksplice/entry/8_gdb_tricks_you_should#command https://blogs.oracle.com/ksplice/entry/8_gdb_tricks_you_shou...) Normally, the "finish" command will interrupt any script you're in the middle of executing, so we have to do a bit of an ugly hack to make sure our script keeps running: b PyEval_EvalFrameEx if strcmp(PyString_AsString(f->f_code->co_name), "handle_uncaught_exception") == 0 commands disable frame 3 python gdb.execute('finish') gdb.execute('shell git stash pop') gdb.execute('call PyImport_ReloadModule(PyImport_AddModule("monospace.views"))') gdb.execute('call PyImport_ReloadModule(PyImport_AddModule("monospace.urls"))') gdb.execute('set $self = PyDict_GetItemString(f->f_locals, "self")') gdb.execute('set $request = PyDict_GetItemString(f->f_locals, "request")') gdb.execute('set $get_response = PyObject_GetAttrString($self, "get_response")') gdb.execute('set $args = Py_BuildValue("(O)", $request)') gdb.execute('set $rax PyObject_Call($get_response, $args, 0)') gdb.execute('enable') gdb.execute('c') end c end (Bah. Edited because I couldn't get monospace text working) You could put those commands into a file and run "gdb -p <my django process> -x <my commands file>" Of course, instead of shelling out to git stash pop, you'd probably want to pause so you could update the code. And you may need to reload more modules than just monospace.views and monospace.urls, depending on the change.
- Luyt 14y ago> Edited because I couldn't get monospace text working If you start each line with a few spaces, HN will format it as source code: b PyEval_EvalFrameEx if strcmp(PyString_AsString(f->f_code->co_name), "handle_uncaught_exception") == 0 commands disable frame 3 python gdb.execute('finish') gdb.execute('shell git stash pop') gdb.execute('call PyImport_ReloadModule(PyImport_AddModule("monospace.views"))') gdb.execute('call PyImport_ReloadModule(PyImport_AddModule("monospace.urls"))') gdb.execute('set $self = PyDict_GetItemString(f->f_locals, "self")') gdb.execute('set $request = PyDict_GetItemString(f->f_locals, "request")') gdb.execute('set $get_response = PyObject_GetAttrString($self, "get_response")') gdb.execute('set $args = Py_BuildValue("(O)", $request)') gdb.execute('set $rax PyObject_Call($get_response, $args, 0)') gdb.execute('enable') gdb.execute('c') end c end
- rmaccloy 14y agoThis actually exists, sort of: http://pyrasite.readthedocs.org/en/latest/index.html http://pyrasite.readthedocs.org/en/latest/index.html I've done this manually a few times, but with foresight attaching signal handlers that open up a port or dump stack (a la `jstack`) is usually less finicky.