[lldb/crashlog] Make interactive mode display more user-friendly

[mib]

Summary

This patch makes the crashlog interactive mode show the scripted process
status with the crashed scripted thread backtrace after launching it.

rdar://89634338

Signed-off-by: Med Ismail Bennani <[e-mail]>

[mib]

Change implementation to emulate lldb's driver

[JDevlieghere]

LGTM. I left a comment with a suggestion for a context manager but that's up to you.

lldb/examples/python/crashlog.py

1024–1025

This is the perfect pattern for a context manager:

@contextlib.contextmanager
def synchronous(debugger):
    async = debugger.GetAsync()
    debugger.SetAsync(False)
    try:
        yield
    finally:
        debugger.SetAsync(async)

and then you can do:

with synchronous(debugger): 
  ...

[mib]

lldb/examples/python/crashlog.py

1024–1025

TIL, very cool!

[mib]

Use context manager pattern

lldb/examples/python/crashlog.py

 #   ( setenv PYTHONPATH /path/to/LLDB.framework/Resources/Python ; ./crashlog.py ~/Library/Logs/DiagnosticReports/a.crash )
 #
 # On MacOSX sh, bash:
 #   PYTHONPATH=/path/to/LLDB.framework/Resources/Python ./crashlog.py ~/Library/Logs/DiagnosticReports/a.crash
 #----------------------------------------------------------------------
 
 from __future__ import print_function
 import cmd
+import contextlib
 import datetime
 import glob
+import json
 import optparse
 import os
 import platform
 import plistlib
 import re
 import shlex
 import string
 import subprocess
 import sys
 import time
 import uuid
-import json
 
 try:
     # First try for LLDB in case PYTHONPATH is already correctly setup.
     import lldb
 except ImportError:
     # Ask the command line driver for the path to the lldb module. Copy over
     # the environment so that SDKROOT is propagated to xcrun.
     command =  ['xcrun', 'lldb', '-P'] if platform.system() == 'Darwin' else ['lldb', '-P']
def load_crashlog_in_scripted_process(debugger, crash_log_file):
     structured_data.SetFromJSON(json.dumps({ "crashlog_path" : crashlog_path }))
     launch_info = lldb.SBLaunchInfo(None)
     launch_info.SetProcessPluginName("ScriptedProcess")
     launch_info.SetScriptedProcessClassName("crashlog_scripted_process.CrashLogScriptedProcess")
     launch_info.SetScriptedProcessDictionary(structured_data)
     error = lldb.SBError()
     process = target.Launch(launch_info, error)
 
+    if not process or error.Fail():
+        return
+
+    @contextlib.contextmanager
+    def synchronous(debugger):
+        async_state = debugger.GetAsync()
+        debugger.SetAsync(False)
+        try:
+            yield
+        finally:
+            debugger.SetAsync(async_state)
+
+    with synchronous(debugger):
+        run_options = lldb.SBCommandInterpreterRunOptions()
+        run_options.SetStopOnError(True)
+        run_options.SetStopOnCrash(True)
+        run_options.SetEchoCommands(True)
+
+        commands_stream = lldb.SBStream()
+        commands_stream.Print("process status\n")
+        commands_stream.Print("thread backtrace\n")
+        error = debugger.SetInputString(commands_stream.GetData())
+        if error.Success():
+            debugger.RunCommandInterpreter(True, False, run_options, 0, False, True)
+
 def CreateSymbolicateCrashLogOptions(
         command_name,
         description,
         add_interactive_options):
     usage = "usage: %prog [options] <FILE> [FILE ...]"
     option_parser = optparse.OptionParser(
         description=description, prog='crashlog', usage=usage)
     option_parser.add_option(

lldb/test/Shell/ScriptInterpreter/Python/Crashlog/scripted_crashlog_json.test

 # REQUIRES: python, native && target-aarch64 && system-darwin
 
 # RUN: %clang_host -g %S/Inputs/test.c -o %t.out
 
 # RUN: cp %S/Inputs/scripted_crashlog.ips %t.crash
 # RUN: %python %S/patch-crashlog.py --binary %t.out --crashlog %t.crash --offsets '{"main":20, "bar":9, "foo":16}' --json
-# RUN: %lldb %t.out -o 'command script import lldb.macosx.crashlog' -o 'crashlog -i %t.crash' -o 'process status' 2>&1 | FileCheck %s
+# RUN: %lldb %t.out -o 'command script import lldb.macosx.crashlog' -o 'crashlog -i %t.crash' 2>&1 | FileCheck %s
 
 # CHECK: "crashlog" {{.*}} commands have been installed, use the "--help" options on these commands
-# CHECK: Process 92190 stopped
-# CHECK: * thread #1, name = 'CrashLogScriptedThread.thread-0', stop reason = EXC_BAD_ACCESS
-# CHECK: frame #0: 0x0000000104a23f68 scripted_crashlog_json.test.tmp.out`foo at test.c:3:6 [artificial]
+# CHECK: (lldb) process status
+# CHECK-NEXT: Process 92190 stopped
+# CHECK-NEXT: * thread #1, name = 'CrashLogScriptedThread.thread-0', stop reason = EXC_BAD_ACCESS
+# CHECK-NEXT: frame #0: 0x0000000104a23f68 scripted_crashlog_json.test.tmp.out`foo at test.c:3:6 [artificial]
+
+# CHECK: (lldb) thread backtrace
+# CHECK-NEXT: * thread #1, name = 'CrashLogScriptedThread.thread-0', stop reason = EXC_BAD_ACCESS
+# CHECK-NEXT: * frame #0: 0x0000000104a23f68 scripted_crashlog_json.test.tmp.out`foo at test.c:3:6 [artificial]
+# CHECK-NEXT: frame #1: 0x0000000104a23f80 scripted_crashlog_json.test.tmp.out`bar at test.c:6:21 [artificial]
+# CHECK-NEXT: frame #2: 0x0000000104a23fa0 scripted_crashlog_json.test.tmp.out`main(argc=<no summary available>, argv=<unavailable>) at test.c:8:35 [artificial]
+# CHECK-NEXT: frame #3: 0x0000000104a6108c dyld`start(kernArgs=<no summary available>) at dyldMain.cpp:879:18 [opt] [artificial]