fix nested pointers issue in array generation and also fix zero length array IR generation

pythonbpf/vmlinux_parser/class_handler.py

@@ -16,10 +16,37 @@ def get_module_symbols(module_name: str):
     return [name for name in dir(imported_module)], imported_module
 
 
+def unwrap_pointer_type(type_obj: Any) -> Any:
+    """
+    Recursively unwrap all pointer layers to get the base type.
+
+    This handles multiply nested pointers like LP_LP_struct_attribute_group
+    and returns the base type (struct_attribute_group).
+
+    Stops unwrapping when reaching a non-pointer type (one without _type_ attribute).
+
+    Args:
+        type_obj: The type object to unwrap
+
+    Returns:
+        The base type after unwrapping all pointer layers
+    """
+    current_type = type_obj
+    # Keep unwrapping while it's a pointer/array type (has _type_)
+    # But stop if _type_ is just a string or basic type marker
+    while hasattr(current_type, "_type_"):
+        next_type = current_type._type_
+        # Stop if _type_ is a string (like 'c' for c_char)
+        if isinstance(next_type, str):
+            break
+        current_type = next_type
+    return current_type
+
+
 def process_vmlinux_class(
-    node,
+        node,
-    llvm_module,
+        llvm_module,
-    handler: DependencyHandler,
+        handler: DependencyHandler,
 ):
     symbols_in_module, imported_module = get_module_symbols("vmlinux")
     if node.name in symbols_in_module:
@@ -30,10 +57,10 @@ def process_vmlinux_class(
 
 
 def process_vmlinux_post_ast(
-    elem_type_class,
+        elem_type_class,
-    llvm_handler,
+        llvm_handler,
-    handler: DependencyHandler,
+        handler: DependencyHandler,
-    processing_stack=None,
+        processing_stack=None,
 ):
     # Initialize processing stack on first call
     if processing_stack is None:
@@ -113,7 +140,7 @@ def process_vmlinux_post_ast(
 
                     # Process pointer to ctype
                     if isinstance(elem_type, type) and issubclass(
-                        elem_type, ctypes._Pointer
+                            elem_type, ctypes._Pointer
                     ):
                         # Get the pointed-to type
                         pointed_type = elem_type._type_
@@ -126,7 +153,7 @@ def process_vmlinux_post_ast(
 
                     # Process function pointers (CFUNCTYPE)
                     elif hasattr(elem_type, "_restype_") and hasattr(
-                        elem_type, "_argtypes_"
+                            elem_type, "_argtypes_"
                     ):
                         # This is a CFUNCTYPE or similar
                         logger.info(
@@ -158,13 +185,19 @@ def process_vmlinux_post_ast(
                         if hasattr(elem_type, "_length_") and is_complex_type:
                             type_length = elem_type._length_
 
-                        if containing_type.__module__ == "vmlinux":
+                        # Unwrap all pointer layers to get the base type for dependency tracking
-                            new_dep_node.add_dependent(
+                        base_type = unwrap_pointer_type(elem_type)
-                                elem_type._type_.__name__
+                        base_type_module = getattr(base_type, "__module__", None)
-                                if hasattr(elem_type._type_, "__name__")
+
-                                else str(elem_type._type_)
+                        if base_type_module == "vmlinux":
+                            base_type_name = (
+                                base_type.__name__
+                                if hasattr(base_type, "__name__")
+                                else str(base_type)
                             )
-                        elif containing_type.__module__ == ctypes.__name__:
+                            new_dep_node.add_dependent(base_type_name)
+                        elif base_type_module == ctypes.__name__ or base_type_module is None:
+                            # Handle ctypes or types with no module (like some internal ctypes types)
                             if isinstance(elem_type, type):
                                 if issubclass(elem_type, ctypes.Array):
                                     ctype_complex_type = ctypes.Array
@@ -178,7 +211,7 @@ def process_vmlinux_post_ast(
                                 raise TypeError("Unsupported ctypes subclass")
                         else:
                             raise ImportError(
-                                f"Unsupported module of {containing_type}"
+                                f"Unsupported module of {base_type}: {base_type_module}"
                             )
                         logger.debug(
                             f"{containing_type} containing type of parent {elem_name} with {elem_type} and ctype {ctype_complex_type} and length {type_length}"
@@ -191,11 +224,16 @@ def process_vmlinux_post_ast(
                             elem_name, ctype_complex_type
                         )
                         new_dep_node.set_field_type(elem_name, elem_type)
-                        if containing_type.__module__ == "vmlinux":
+
+                        # Check the containing_type module to decide whether to recurse
+                        containing_type_module = getattr(containing_type, "__module__", None)
+                        if containing_type_module == "vmlinux":
+                            # Also unwrap containing_type to get base type name
+                            base_containing_type = unwrap_pointer_type(containing_type)
                             containing_type_name = (
-                                containing_type.__name__
+                                base_containing_type.__name__
-                                if hasattr(containing_type, "__name__")
+                                if hasattr(base_containing_type, "__name__")
-                                else str(containing_type)
+                                else str(base_containing_type)
                             )
 
                             # Check for self-reference or already processed
@@ -212,21 +250,21 @@ def process_vmlinux_post_ast(
                                 )
                                 new_dep_node.set_field_ready(elem_name, True)
                             else:
-                                # Process recursively - THIS WAS MISSING
+                                # Process recursively - use base containing type, not the pointer wrapper
                                 new_dep_node.add_dependent(containing_type_name)
                                 process_vmlinux_post_ast(
-                                    containing_type,
+                                    base_containing_type,
                                     llvm_handler,
                                     handler,
                                     processing_stack,
                                 )
                                 new_dep_node.set_field_ready(elem_name, True)
-                        elif containing_type.__module__ == ctypes.__name__:
+                        elif containing_type_module == ctypes.__name__ or containing_type_module is None:
                             logger.debug(f"Processing ctype internal{containing_type}")
                             new_dep_node.set_field_ready(elem_name, True)
                         else:
                             raise TypeError(
-                                "Module not supported in recursive resolution"
+                                f"Module not supported in recursive resolution: {containing_type_module}"
                             )
                     else:
                         new_dep_node.add_dependent(
@@ -245,9 +283,12 @@ def process_vmlinux_post_ast(
                     raise ValueError(
                         f"{elem_name} with type {elem_type} from module {module_name} not supported in recursive resolver"
                     )
-
+    elif module_name == ctypes.__name__ or module_name is None:
+        # Handle ctypes types - these don't need processing, just return
+        logger.debug(f"Skipping ctypes type {current_symbol_name}")
+        return True
     else:
-        raise ImportError("UNSUPPORTED Module")
+        raise ImportError(f"UNSUPPORTED Module {module_name}")
 
     logger.info(
         f"{current_symbol_name} processed and handler readiness {handler.is_ready}"

pythonbpf/vmlinux_parser/import_detector.py

@@ -11,7 +11,9 @@ from .class_handler import process_vmlinux_class
 logger = logging.getLogger(__name__)
 
 
-def detect_import_statement(tree: ast.AST) -> list[tuple[str, ast.ImportFrom]]:
+def detect_import_statement(
+    tree: ast.AST,
+) -> list[tuple[str, ast.ImportFrom, str, str]]:
     """
     Parse AST and detect import statements from vmlinux.
 
@@ -25,7 +27,7 @@ def detect_import_statement(tree: ast.AST) -> list[tuple[str, ast.ImportFrom]]:
         List of tuples containing (module_name, imported_item) for each vmlinux import
 
     Raises:
-        SyntaxError: If multiple imports from vmlinux are attempted or import * is used
+        SyntaxError: If import * is used
     """
     vmlinux_imports = []
 
@@ -40,28 +42,19 @@ def detect_import_statement(tree: ast.AST) -> list[tuple[str, ast.ImportFrom]]:
                         "Please import specific types explicitly."
                     )
 
-                # Check for multiple imports: from vmlinux import A, B, C
-                if len(node.names) > 1:
-                    imported_names = [alias.name for alias in node.names]
-                    raise SyntaxError(
-                        f"Multiple imports from vmlinux are not supported. "
-                        f"Found: {', '.join(imported_names)}. "
-                        f"Please use separate import statements for each type."
-                    )
-
                 # Check if no specific import is specified (should not happen with valid Python)
                 if len(node.names) == 0:
                     raise SyntaxError(
                         "Import from vmlinux must specify at least one type."
                     )
 
-                # Valid single import
+                # Support multiple imports: from vmlinux import A, B, C
                 for alias in node.names:
                     import_name = alias.name
-                    # Use alias if provided, otherwise use the original name (commented)
+                    # Use alias if provided, otherwise use the original name
-                    # as_name = alias.asname if alias.asname else alias.name
+                    as_name = alias.asname if alias.asname else alias.name
-                    vmlinux_imports.append(("vmlinux", node))
+                    vmlinux_imports.append(("vmlinux", node, import_name, as_name))
-                    logger.info(f"Found vmlinux import: {import_name}")
+                    logger.info(f"Found vmlinux import: {import_name} as {as_name}")
 
         # Handle "import vmlinux" statements (not typical but should be rejected)
         elif isinstance(node, ast.Import):
@@ -73,6 +66,7 @@ def detect_import_statement(tree: ast.AST) -> list[tuple[str, ast.ImportFrom]]:
                     )
 
     logger.info(f"Total vmlinux imports detected: {len(vmlinux_imports)}")
+    # print(f"\n**************\n{vmlinux_imports}\n**************\n")
     return vmlinux_imports
 
 
@@ -103,40 +97,37 @@ def vmlinux_proc(tree: ast.AST, module):
     with open(source_file, "r") as f:
         mod_ast = ast.parse(f.read(), filename=source_file)
 
-    for import_mod, import_node in import_statements:
+    for import_mod, import_node, imported_name, as_name in import_statements:
-        for alias in import_node.names:
+        found = False
-            imported_name = alias.name
+        for mod_node in mod_ast.body:
-            found = False
+            if isinstance(mod_node, ast.ClassDef) and mod_node.name == imported_name:
-            for mod_node in mod_ast.body:
+                process_vmlinux_class(mod_node, module, handler)
-                if (
+                found = True
-                    isinstance(mod_node, ast.ClassDef)
+                break
-                    and mod_node.name == imported_name
+            if isinstance(mod_node, ast.Assign):
-                ):
+                for target in mod_node.targets:
-                    process_vmlinux_class(mod_node, module, handler)
+                    if isinstance(target, ast.Name) and target.id == imported_name:
-                    found = True
+                        process_vmlinux_assign(mod_node, module, assignments, as_name)
-                    break
+                        found = True
-                if isinstance(mod_node, ast.Assign):
+                        break
-                    for target in mod_node.targets:
+            if found:
-                        if isinstance(target, ast.Name) and target.id == imported_name:
+                break
-                            process_vmlinux_assign(mod_node, module, assignments)
+        if not found:
-                            found = True
+            logger.info(f"{imported_name} not found as ClassDef or Assign in vmlinux")
-                            break
-                if found:
-                    break
-            if not found:
-                logger.info(
-                    f"{imported_name} not found as ClassDef or Assign in vmlinux"
-                )
 
     IRGenerator(module, handler, assignments)
     return assignments
 
 
-def process_vmlinux_assign(node, module, assignments: dict[str, AssignmentInfo]):
+def process_vmlinux_assign(
+    node, module, assignments: dict[str, AssignmentInfo], target_name=None
+):
     """Process assignments from vmlinux module."""
     # Only handle single-target assignments
     if len(node.targets) == 1 and isinstance(node.targets[0], ast.Name):
-        target_name = node.targets[0].id
+        # Use provided target_name (for aliased imports) or fall back to original name
+        if target_name is None:
+            target_name = node.targets[0].id
 
         # Handle constant value assignments
         if isinstance(node.value, ast.Constant):

pythonbpf/vmlinux_parser/ir_gen/debug_info_gen.py

@@ -46,13 +46,14 @@ def debug_info_generation(
 
     if struct.name.startswith("struct_"):
         struct_name = struct.name.removeprefix("struct_")
+        # Create struct type with all members
+        struct_type = generator.create_struct_type_with_name(
+            struct_name, members, struct.__sizeof__() * 8, is_distinct=True
+        )
     else:
-        raise ValueError("Unions are not supported in the current version")
+        logger.warning("Blindly handling Unions present in vmlinux dependencies")
-    # Create struct type with all members
+        struct_type = None
-    struct_type = generator.create_struct_type_with_name(
+        # raise ValueError("Unions are not supported in the current version")
-        struct_name, members, struct.__sizeof__() * 8, is_distinct=True
-    )
-
     return struct_type
 
 
@@ -62,7 +63,7 @@ def _get_field_debug_type(
     generator: DebugInfoGenerator,
     parent_struct: DependencyNode,
     generated_debug_info: List[Tuple[DependencyNode, Any]],
-) -> tuple[Any, int]:
+) -> tuple[Any, int] | None:
     """
     Determine the appropriate debug type for a field based on its Python/ctypes type.
 
@@ -78,7 +79,11 @@ def _get_field_debug_type(
     """
     # Handle complex types (arrays, pointers)
     if field.ctype_complex_type is not None:
-        if issubclass(field.ctype_complex_type, ctypes.Array):
+        #TODO: Check if this is a CFUNCTYPE (function pointer), but sadly it just checks callable for now
+        if callable(field.ctype_complex_type):
+            # Handle function pointer types, create a void pointer as a placeholder
+            return generator.create_pointer_type(None), 64
+        elif issubclass(field.ctype_complex_type, ctypes.Array):
             # Handle array types
             element_type, base_type_size = _get_basic_debug_type(
                 field.containing_type, generator

pythonbpf/vmlinux_parser/ir_gen/ir_generation.py

@@ -11,6 +11,9 @@ logger = logging.getLogger(__name__)
 
 
 class IRGenerator:
+    # This field keeps track of the non_struct names to avoid duplicate name errors.
+    type_number = 0
+    unprocessed_store = []
     # get the assignments dict and add this stuff to it.
     def __init__(self, llvm_module, handler: DependencyHandler, assignments):
         self.llvm_module = llvm_module
@@ -68,6 +71,7 @@ class IRGenerator:
                                 dep_node_from_dependency, processing_stack
                             )
                         else:
+                            print(struct)
                             raise RuntimeError(
                                 f"Warning: Dependency {dependency} not found in handler"
                             )
@@ -82,6 +86,7 @@ class IRGenerator:
                 members_dict = {}
                 for field_name, field in struct.fields.items():
                     # Get the generated field name from our dictionary, or use field_name if not found
+                    print(f"DEBUG: {struct.name}, {field_name}")
                     if (
                         struct.name in self.generated_field_names
                         and field_name in self.generated_field_names[struct.name]
@@ -129,7 +134,20 @@ class IRGenerator:
 
         for field_name, field in struct.fields.items():
             # does not take arrays and similar types into consideration yet.
-            if field.ctype_complex_type is not None and issubclass(
+            if callable(field.ctype_complex_type):
+                # Function pointer case - generate a simple field accessor
+                field_co_re_name, returned = self._struct_name_generator(
+                    struct, field, field_index
+                )
+                print(field_co_re_name)
+                field_index += 1
+                globvar = ir.GlobalVariable(
+                    self.llvm_module, ir.IntType(64), name=field_co_re_name
+                )
+                globvar.linkage = "external"
+                globvar.set_metadata("llvm.preserve.access.index", debug_info)
+                self.generated_field_names[struct.name][field_name] = globvar
+            elif field.ctype_complex_type is not None and issubclass(
                 field.ctype_complex_type, ctypes.Array
             ):
                 array_size = field.type_size
@@ -137,7 +155,7 @@ class IRGenerator:
                 if containing_type.__module__ == ctypes.__name__:
                     containing_type_size = ctypes.sizeof(containing_type)
                     if array_size == 0:
-                        field_co_re_name = self._struct_name_generator(
+                        field_co_re_name, returned = self._struct_name_generator(
                             struct, field, field_index, True, 0, containing_type_size
                         )
                         globvar = ir.GlobalVariable(
@@ -149,7 +167,7 @@ class IRGenerator:
                         field_index += 1
                         continue
                     for i in range(0, array_size):
-                        field_co_re_name = self._struct_name_generator(
+                        field_co_re_name, returned = self._struct_name_generator(
                             struct, field, field_index, True, i, containing_type_size
                         )
                         globvar = ir.GlobalVariable(
@@ -163,12 +181,26 @@ class IRGenerator:
                 array_size = field.type_size
                 containing_type = field.containing_type
                 if containing_type.__module__ == "vmlinux":
-                    containing_type_size = self.handler[
+                    print(struct)
-                        containing_type.__name__
+                    # Unwrap all pointer layers to get the base struct type
-                    ].current_offset
+                    base_containing_type = containing_type
-                    for i in range(0, array_size):
+                    while hasattr(base_containing_type, "_type_"):
-                        field_co_re_name = self._struct_name_generator(
+                        next_type = base_containing_type._type_
-                            struct, field, field_index, True, i, containing_type_size
+                        # Stop if _type_ is a string (like 'c' for c_char)
+                        #TODO: stacked pointers not handl;ing ctypes check here as well
+                        if isinstance(next_type, str):
+                            break
+                        base_containing_type = next_type
+
+                    # Get the base struct name
+                    base_struct_name = base_containing_type.__name__ if hasattr(base_containing_type, "__name__") else str(base_containing_type)
+
+                    # Look up the size using the base struct name
+                    containing_type_size = self.handler[base_struct_name].current_offset
+                    print(f"GAY: {array_size}, {struct.name}, {field_name}")
+                    if array_size == 0:
+                        field_co_re_name, returned = self._struct_name_generator(
+                            struct, field, field_index, True, 0, containing_type_size
                         )
                         globvar = ir.GlobalVariable(
                             self.llvm_module, ir.IntType(64), name=field_co_re_name
@@ -176,9 +208,21 @@ class IRGenerator:
                         globvar.linkage = "external"
                         globvar.set_metadata("llvm.preserve.access.index", debug_info)
                         self.generated_field_names[struct.name][field_name] = globvar
-                    field_index += 1
+                        field_index += 1
+                    else:
+                        for i in range(0, array_size):
+                            field_co_re_name, returned = self._struct_name_generator(
+                                struct, field, field_index, True, i, containing_type_size
+                            )
+                            globvar = ir.GlobalVariable(
+                                self.llvm_module, ir.IntType(64), name=field_co_re_name
+                            )
+                            globvar.linkage = "external"
+                            globvar.set_metadata("llvm.preserve.access.index", debug_info)
+                            self.generated_field_names[struct.name][field_name] = globvar
+                        field_index += 1
             else:
-                field_co_re_name = self._struct_name_generator(
+                field_co_re_name, returned = self._struct_name_generator(
                     struct, field, field_index
                 )
                 field_index += 1
@@ -198,7 +242,7 @@ class IRGenerator:
         is_indexed: bool = False,
         index: int = 0,
         containing_type_size: int = 0,
-    ) -> str:
+    ) -> tuple[str, bool]:
         # TODO: Does not support Unions as well as recursive pointer and array type naming
         if is_indexed:
             name = (
@@ -208,7 +252,7 @@ class IRGenerator:
                 + "$"
                 + f"0:{field_index}:{index}"
             )
-            return name
+            return name, True
         elif struct.name.startswith("struct_"):
             name = (
                 "llvm."
@@ -217,9 +261,18 @@ class IRGenerator:
                 + "$"
                 + f"0:{field_index}"
             )
-            return name
+            return name, True
         else:
-            print(self.handler[struct.name])
+            logger.warning(
-            raise TypeError(
+                "Blindly handling non-struct type to avoid type errors in vmlinux IR generation. Possibly a union."
-                "Name generation cannot occur due to type name not starting with struct"
             )
+            self.type_number += 1
+            unprocessed_type = "unprocessed_type_" + str(self.handler[struct.name].name)
+            if self.unprocessed_store.__contains__(unprocessed_type):
+                return unprocessed_type + "_" + str(self.type_number), False
+            else:
+                self.unprocessed_store.append(unprocessed_type)
+                return unprocessed_type,  False
+            # raise TypeError(
+            #     "Name generation cannot occur due to type name not starting with struct"
+            # )

tests/failing_tests/vmlinux/requests.py

@@ -0,0 +1,21 @@
+from vmlinux import struct_request, struct_pt_regs, XDP_PASS
+from pythonbpf import bpf, section, bpfglobal, compile_to_ir
+import logging
+
+
+@bpf
+@section("kprobe/blk_mq_start_request")
+def example(ctx: struct_pt_regs):
+    req = struct_request(ctx.di)
+    c = req.__data_len
+    d = XDP_PASS
+    print(f"data length {c} and test {d}")
+
+
+@bpf
+@bpfglobal
+def LICENSE() -> str:
+    return "GPL"
+
+
+compile_to_ir("requests.py", "requests.ll", loglevel=logging.INFO)

tests/failing_tests/vmlinux/requests2.py

@@ -0,0 +1,19 @@
+from vmlinux import struct_kobj_type
+from pythonbpf import bpf, section, bpfglobal, compile_to_ir
+import logging
+from ctypes import c_void_p
+
+
+@bpf
+@section("kprobe/blk_mq_start_request")
+def example(ctx: c_void_p):
+    print(f"data lengt")
+
+
+@bpf
+@bpfglobal
+def LICENSE() -> str:
+    return "GPL"
+
+
+compile_to_ir("requests.py", "requests.ll", loglevel=logging.INFO)