#
# This file defines the layer that talks to lldb
#
import os, re, sys
import lldb
import vim
from vim_ui import UI
# =================================================
# Convert some enum value to its string counterpart
# =================================================
# Shamelessly copy/pasted from lldbutil.py in the test suite
def state_type_to_str(enum):
"""Returns the stateType string given an enum."""
if enum == lldb.eStateInvalid:
return "invalid"
elif enum == lldb.eStateUnloaded:
return "unloaded"
elif enum == lldb.eStateConnected:
return "connected"
elif enum == lldb.eStateAttaching:
return "attaching"
elif enum == lldb.eStateLaunching:
return "launching"
elif enum == lldb.eStateStopped:
return "stopped"
elif enum == lldb.eStateRunning:
return "running"
elif enum == lldb.eStateStepping:
return "stepping"
elif enum == lldb.eStateCrashed:
return "crashed"
elif enum == lldb.eStateDetached:
return "detached"
elif enum == lldb.eStateExited:
return "exited"
elif enum == lldb.eStateSuspended:
return "suspended"
else:
raise Exception("Unknown StateType enum")
class StepType:
INSTRUCTION = 1
INSTRUCTION_OVER = 2
INTO = 3
OVER = 4
OUT = 5
class LLDBController(object):
""" Handles Vim and LLDB events such as commands and lldb events. """
# Timeouts (sec) for waiting on new events. Because vim is not multi-threaded, we are restricted to
# servicing LLDB events from the main UI thread. Usually, we only process events that are already
# sitting on the queue. But in some situations (when we are expecting an event as a result of some
# user interaction) we want to wait for it. The constants below set these wait period in which the
# Vim UI is "blocked". Lower numbers will make Vim more responsive, but LLDB will be delayed and higher
# numbers will mean that LLDB events are processed faster, but the Vim UI may appear less responsive at
# times.
eventDelayStep = 2
eventDelayLaunch = 1
eventDelayContinue = 1
def __init__(self):
""" Creates the LLDB SBDebugger object and initializes the UI class. """
self.target = None
self.process = None
self.load_dependent_modules = True
self.dbg = lldb.SBDebugger.Create()
self.commandInterpreter = self.dbg.GetCommandInterpreter()
self.ui = UI()
def completeCommand(self, a, l, p):
""" Returns a list of viable completions for command a with length l and cursor at p """
assert l[0] == 'L'
# Remove first 'L' character that all commands start with
l = l[1:]
# Adjust length as string has 1 less character
p = int(p) - 1
result = lldb.SBStringList()
num = self.commandInterpreter.HandleCompletion(l, p, 1, -1, result)
if num == -1:
# FIXME: insert completion character... what's a completion character?
pass
elif num == -2:
# FIXME: replace line with result.GetStringAtIndex(0)
pass
if result.GetSize() > 0:
results = filter(None, [result.GetStringAtIndex(x) for x in range(result.GetSize())])
return results
else:
return []
def doStep(self, stepType):
""" Perform a step command and block the UI for eventDelayStep seconds in order to process
events on lldb's event queue.
FIXME: if the step does not complete in eventDelayStep seconds, we relinquish control to
the main thread to avoid the appearance of a "hang". If this happens, the UI will
update whenever; usually when the user moves the cursor. This is somewhat annoying.
"""
if not self.process:
sys.stderr.write("No process to step")
return
t = self.process.GetSelectedThread()
if stepType == StepType.INSTRUCTION:
t.StepInstruction(False)
if stepType == StepType.INSTRUCTION_OVER:
t.StepInstruction(True)
elif stepType == StepType.INTO:
t.StepInto()
elif stepType == StepType.OVER:
t.StepOver()
elif stepType == StepType.OUT:
t.StepOut()
self.processPendingEvents(self.eventDelayStep, True)
def doSelect(self, command, args):
""" Like doCommand, but suppress output when "select" is the first argument."""
a = args.split(' ')
return self.doCommand(command, args, "select" != a[0], True)
def doProcess(self, args):
""" Handle 'process' command. If 'launch' is requested, use doLaunch() instead
of the command interpreter to start the inferior process.
"""
a = args.split(' ')
if len(args) == 0 or (len(a) > 0 and a[0] != 'launch'):
self.doCommand("process", args)
#self.ui.update(self.target, "", self)
else:
self.doLaunch('-s' not in args, "")
def doAttach(self, process_name):
""" Handle process attach. """
error = lldb.SBError()
self.processListener = lldb.SBListener("process_event_listener")
self.target = self.dbg.CreateTarget('')
self.process = self.target.AttachToProcessWithName(self.processListener, process_name, False, error)
if not error.Success():
sys.stderr.write("Error during attach: " + str(error))
return
self.ui.activate()
self.pid = self.process.GetProcessID()
print "Attached to %s (pid=%d)" % (process_name, self.pid)
def doDetach(self):
if self.process is not None and self.process.IsValid():
pid = self.process.GetProcessID()
state = state_type_to_str(self.process.GetState())
self.process.Detach()
self.processPendingEvents(self.eventDelayLaunch)
def doLaunch(self, stop_at_entry, args):
""" Handle process launch. """
error = lldb.SBError()
fs = self.target.GetExecutable()
exe = os.path.join(fs.GetDirectory(), fs.GetFilename())
if self.process is not None and self.process.IsValid():
pid = self.process.GetProcessID()
state = state_type_to_str(self.process.GetState())
self.process.Destroy()
launchInfo = lldb.SBLaunchInfo(args.split(' '))
self.process = self.target.Launch(launchInfo, error)
if not error.Success():
sys.stderr.write("Error during launch: " + str(error))
return
# launch succeeded, store pid and add some event listeners
self.pid = self.process.GetProcessID()
self.processListener = lldb.SBListener("process_event_listener")
self.process.GetBroadcaster().AddListener(self.processListener, lldb.SBProcess.eBroadcastBitStateChanged)
print "Launched %s %s (pid=%d)" % (exe, args, self.pid)
if not stop_at_entry:
self.doContinue()
else:
self.processPendingEvents(self.eventDelayLaunch)
def doTarget(self, args):
""" Pass target command to interpreter, except if argument is not one of the valid options, or
is create, in which case try to create a target with the argument as the executable. For example:
target list ==> handled by interpreter
target create blah ==> custom creation of target 'blah'
target blah ==> also creates target blah
"""
target_args = [#"create",
"delete",
"list",
"modules",
"select",
"stop-hook",
"symbols",
"variable"]
a = args.split(' ')
if len(args) == 0 or (len(a) > 0 and a[0] in target_args):
self.doCommand("target", args)
return
elif len(a) > 1 and a[0] == "create":
exe = a[1]
elif len(a) == 1 and a[0] not in target_args:
exe = a[0]
err = lldb.SBError()
self.target = self.dbg.CreateTarget(exe, None, None, self.load_dependent_modules, err)
if not self.target:
sys.stderr.write("Error creating target %s. %s" % (str(exe), str(err)))
return
self.ui.activate()
self.ui.update(self.target, "created target %s" % str(exe), self)
def doContinue(self):
""" Handle 'contiue' command.
FIXME: switch to doCommand("continue", ...) to handle -i ignore-count param.
"""
if not self.process or not self.process.IsValid():
sys.stderr.write("No process to continue")
return
self.process.Continue()
self.processPendingEvents(self.eventDelayContinue)
def doBreakpoint(self, args):
""" Handle breakpoint command with command interpreter, except if the user calls
"breakpoint" with no other args, in which case add a breakpoint at the line
under the cursor.
"""
a = args.split(' ')
if len(args) == 0:
show_output = False
# User called us with no args, so toggle the bp under cursor
cw = vim.current.window
cb = vim.current.buffer
name = cb.name
line = cw.cursor[0]
# Since the UI is responsbile for placing signs at bp locations, we have to
# ask it if there already is one or more breakpoints at (file, line)...
if self.ui.haveBreakpoint(name, line):
bps = self.ui.getBreakpoints(name, line)
args = "delete %s" % " ".join([str(b.GetID()) for b in bps])
self.ui.deleteBreakpoints(name, line)
else:
args = "set -f %s -l %d" % (name, line)
else:
show_output = True
self.doCommand("breakpoint", args, show_output)
return
def doRefresh(self):
""" process pending events and update UI on request """
status = self.processPendingEvents()
def doShow(self, name):
""" handle :Lshow <name> """
if not name:
self.ui.activate()
return
if self.ui.showWindow(name):
self.ui.update(self.target, "", self)
def doHide(self, name):
""" handle :Lhide <name> """
if self.ui.hideWindow(name):
self.ui.update(self.target, "", self)
def doExit(self):
self.dbg.Terminate()
self.dbg = None
def getCommandResult(self, command, command_args):
""" Run cmd in the command interpreter and returns (success, output) """
result = lldb.SBCommandReturnObject()
cmd = "%s %s" % (command, command_args)
self.commandInterpreter.HandleCommand(cmd, result)
return (result.Succeeded(), result.GetOutput() if result.Succeeded() else result.GetError())
def doCommand(self, command, command_args, print_on_success = True, goto_file=False):
""" Run cmd in interpreter and print result (success or failure) on the vim status line. """
(success, output) = self.getCommandResult(command, command_args)
if success:
self.ui.update(self.target, "", self, goto_file)
if len(output) > 0 and print_on_success:
print output
else:
sys.stderr.write(output)
def getCommandOutput(self, command, command_args=""):
""" runs cmd in the command interpreter andreturns (status, result) """
result = lldb.SBCommandReturnObject()
cmd = "%s %s" % (command, command_args)
self.commandInterpreter.HandleCommand(cmd, result)
return (result.Succeeded(), result.GetOutput() if result.Succeeded() else result.GetError())
def processPendingEvents(self, wait_seconds=0, goto_file=True):
""" Handle any events that are queued from the inferior.
Blocks for at most wait_seconds, or if wait_seconds == 0,
process only events that are already queued.
"""
status = None
num_events_handled = 0
if self.process is not None:
event = lldb.SBEvent()
old_state = self.process.GetState()
new_state = None
done = False
if old_state == lldb.eStateInvalid or old_state == lldb.eStateExited:
# Early-exit if we are in 'boring' states
pass
else:
while not done and self.processListener is not None:
if not self.processListener.PeekAtNextEvent(event):
if wait_seconds > 0:
# No events on the queue, but we are allowed to wait for wait_seconds
# for any events to show up.
self.processListener.WaitForEvent(wait_seconds, event)
new_state = lldb.SBProcess.GetStateFromEvent(event)
num_events_handled += 1
done = not self.processListener.PeekAtNextEvent(event)
else:
# An event is on the queue, process it here.
self.processListener.GetNextEvent(event)
new_state = lldb.SBProcess.GetStateFromEvent(event)
# continue if stopped after attaching
if old_state == lldb.eStateAttaching and new_state == lldb.eStateStopped:
self.process.Continue()
# If needed, perform any event-specific behaviour here
num_events_handled += 1
if num_events_handled == 0:
pass
else:
if old_state == new_state:
status = ""
self.ui.update(self.target, status, self, goto_file)
def returnCompleteCommand(a, l, p):
""" Returns a "\n"-separated string with possible completion results
for command a with length l and cursor at p.
"""
separator = "\n"
results = ctrl.completeCommand(a, l, p)
vim.command('return "%s%s"' % (separator.join(results), separator))
def returnCompleteWindow(a, l, p):
""" Returns a "\n"-separated string with possible completion results
for commands that expect a window name parameter (like hide/show).
FIXME: connect to ctrl.ui instead of hardcoding the list here
"""
separator = "\n"
results = ['breakpoints', 'backtrace', 'disassembly', 'locals', 'threads', 'registers']
vim.command('return "%s%s"' % (separator.join(results), separator))
global ctrl
ctrl = LLDBController()