gdb/python/lib/gdb/dap/next.py

   1 # Copyright 2022-2024 Free Software Foundation, Inc.
   2
   3 # This program is free software; you can redistribute it and/or modify
   4 # it under the terms of the GNU General Public License as published by
   5 # the Free Software Foundation; either version 3 of the License, or
   6 # (at your option) any later version.
   7 #
   8 # This program is distributed in the hope that it will be useful,
   9 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 # GNU General Public License for more details.
  12 #
  13 # You should have received a copy of the GNU General Public License
  14 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15
  16 import gdb
  17
  18 from .events import exec_and_expect_stop
  19 from .server import capability, request
  20 from .startup import in_gdb_thread, send_gdb, send_gdb_with_response
  21 from .state import set_thread
  22
  23
  24 # Helper function to set the current thread and the scheduler-locking
  25 # mode.  Returns True if scheduler-locking was successfully set to
  26 # 'on', False in all other cases, including error.  When SELECT is
  27 # True, also select that thread's newest frame.
  28 @in_gdb_thread
  29 def _handle_thread_step(thread_id, single_thread, select=False):
  30     # Ensure we're going to step the correct thread.
  31     set_thread(thread_id)
  32     if single_thread:
  33         result = True
  34         arg = "on"
  35     else:
  36         result = False
  37         arg = "off"
  38     try:
  39         # This can fail, depending on the target, so catch the error
  40         # and report to our caller.  We can't use exec_and_log because
  41         # that does not propagate exceptions.
  42         gdb.execute("set scheduler-locking " + arg, from_tty=True, to_string=True)
  43     except gdb.error:
  44         result = False
  45     # Other DAP code may select a frame, and the "finish" command uses
  46     # the selected frame.
  47     if select:
  48         gdb.newest_frame().select()
  49     return result
  50
  51
  52 @request("next", response=False)
  53 def next(
  54     *, threadId: int, singleThread: bool = False, granularity: str = "statement", **args
  55 ):
  56     _handle_thread_step(threadId, singleThread)
  57     cmd = "next"
  58     if granularity == "instruction":
  59         cmd += "i"
  60     exec_and_expect_stop(cmd)
  61
  62
  63 @capability("supportsSteppingGranularity")
  64 @capability("supportsSingleThreadExecutionRequests")
  65 @request("stepIn", response=False)
  66 def step_in(
  67     *, threadId: int, singleThread: bool = False, granularity: str = "statement", **args
  68 ):
  69     _handle_thread_step(threadId, singleThread)
  70     cmd = "step"
  71     if granularity == "instruction":
  72         cmd += "i"
  73     exec_and_expect_stop(cmd)
  74
  75
  76 @request("stepOut", response=False)
  77 def step_out(*, threadId: int, singleThread: bool = False, **args):
  78     _handle_thread_step(threadId, singleThread, True)
  79     exec_and_expect_stop("finish")
  80
  81
  82 # This is a server-side request because it is funny: it wants to
  83 # 'continue' but also return a result, which precludes using
  84 # response=False.  Using 'continue &' would mostly work ok, but this
  85 # yields races when a stop occurs before the response is sent back to
  86 # the client.
  87 @request("continue", on_dap_thread=True)
  88 def continue_request(*, threadId: int, singleThread: bool = False, **args):
  89     locked = send_gdb_with_response(lambda: _handle_thread_step(threadId, singleThread))
  90     send_gdb(lambda: exec_and_expect_stop("continue"))
  91     return {"allThreadsContinued": not locked}