Allow option to ignore module load errors in ScriptedProcess (#127153)

Current state in scripted process expects [all the
modules](https://github.com/llvm/llvm-project/blob/912b154f3a3f8c3cebf5cc5731fd8b0749762da5/lldb/source/Plugins/Process/scripted/ScriptedProcess.cpp#L498)
passed into "get_loaded_images" to load successfully else none of them
load. Even if a module loads fine, [but has already been
appended](https://github.com/llvm/llvm-project/blob/912b154f3a3f8c3cebf5cc5731fd8b0749762da5/lldb/source/Plugins/Process/scripted/ScriptedProcess.cpp#L495)
it still fails. This is restrictive and does not help our usecase.

**Usecase**: We have a parent scripted process using coredump +
tombstone.

1) Scripted process uses child elf-core process to read memory dump

2) Uses tombstones to pass thread names and modules.

We do not know whether the modules will be successfully downloaded
before creating the scripted process. We use [python module
callbacks](https://github.com/llvm/llvm-project/blob/a57e58dbfaae0e86eb5cafeddf8b598f14b96e36/lldb/source/Target/Platform.cpp#L1593)
to download a module from symbol server at LLDB load time when the
scripted process is being created. The issue is that if one of the
symbol is not found from the list specified in tombstone, none of the
modules load in scripted process. Even if we ensure symbols are present
in symbol server before creating the scripted process, if the load
address is wrong or if the module is already appended, all module loads
are skipped.

**Solution**: Pass in a custom boolean option arg for every module from
python scripted process plugin which will indicate whether to ignore the
module load error. This will provide the flexibility to user for loading
the successfully fetched modules into target while ignoring the failed
ones

---------

Co-authored-by: rchamala <rachamal@fb.com>

1 files changed, 15 insertions, 1 deletions

diff --git a/lldb/test/API/functionalities/scripted_process/TestStackCoreScriptedProcess.py b/lldb/test/API/functionalities/scripted_process/TestStackCoreScriptedProcess.py
index a5c79378bab5..22b0d01c2c17 100644
--- a/lldb/test/API/functionalities/scripted_process/TestStackCoreScriptedProcess.py
+++ b/lldb/test/API/functionalities/scripted_process/TestStackCoreScriptedProcess.py
@@ -76,6 +76,12 @@ class StackCoreScriptedProcesTestCase(TestBase):
             )
         self.assertTrue(corefile_process, PROCESS_IS_VALID)
 
+        # Create a random lib which does not exist in the corefile.
+        random_dylib = self.get_module_with_name(corefile_target, "random.dylib")
+        self.assertFalse(
+            random_dylib, "Dynamic library random.dylib should not be found."
+        )
+
         structured_data = lldb.SBStructuredData()
         structured_data.SetFromJSON(
             json.dumps(
@@ -83,7 +89,15 @@ class StackCoreScriptedProcesTestCase(TestBase):
                     "backing_target_idx": self.dbg.GetIndexOfTarget(
                         corefile_process.GetTarget()
                     ),
-                    "libbaz_path": self.getBuildArtifact("libbaz.dylib"),
+                    "custom_modules": [
+                        {
+                            "path": self.getBuildArtifact("libbaz.dylib"),
+                        },
+                        {
+                            "path": "/random/path/random.dylib",
+                            "load_addr": 12345678,
+                        },
+                    ],
                 }
             )
         )