psloop.c

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 *              Status              - Parse status before complete Op
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Complete Op
 *
 ******************************************************************************/

static acpi_status
acpi_ps_complete_op(struct acpi_walk_state *walk_state,
		    union acpi_parse_object **op, acpi_status status)
{
	acpi_status status2;

	ACPI_FUNCTION_TRACE_PTR(ps_complete_op, walk_state);

	/*
	 * Finished one argument of the containing scope
	 */
	walk_state->parser_state.scope->parse_scope.arg_count--;

	/* Close this Op (will result in parse subtree deletion) */

	status2 = acpi_ps_complete_this_op(walk_state, *op);
	if (ACPI_FAILURE(status2)) {
		return_ACPI_STATUS(status2);
	}

	*op = NULL;

	switch (status) {
	case AE_OK:
		break;

	case AE_CTRL_TRANSFER:

		/* We are about to transfer to a called method */

		walk_state->prev_op = NULL;
		walk_state->prev_arg_types = walk_state->arg_types;
		return_ACPI_STATUS(status);

	case AE_CTRL_END:

		acpi_ps_pop_scope(&(walk_state->parser_state), op,
				  &walk_state->arg_types,
				  &walk_state->arg_count);

		if (*op) {
			walk_state->op = *op;
			walk_state->op_info =
			    acpi_ps_get_opcode_info((*op)->common.aml_opcode);
			walk_state->opcode = (*op)->common.aml_opcode;

			status = walk_state->ascending_callback(walk_state);
			status =
			    acpi_ps_next_parse_state(walk_state, *op, status);

			status2 = acpi_ps_complete_this_op(walk_state, *op);
			if (ACPI_FAILURE(status2)) {
				return_ACPI_STATUS(status2);
			}
		}

		status = AE_OK;
		break;

	case AE_CTRL_BREAK:
	case AE_CTRL_CONTINUE:

		/* Pop off scopes until we find the While */

		while (!(*op) || ((*op)->common.aml_opcode != AML_WHILE_OP)) {
			acpi_ps_pop_scope(&(walk_state->parser_state), op,
					  &walk_state->arg_types,
					  &walk_state->arg_count);

			if ((*op)->common.aml_opcode != AML_WHILE_OP) {
				status2 = acpi_ds_result_stack_pop(walk_state);
				if (ACPI_FAILURE(status2)) {
					return_ACPI_STATUS(status2);
				}
			}
		}

		/* Close this iteration of the While loop */

		walk_state->op = *op;
		walk_state->op_info =
		    acpi_ps_get_opcode_info((*op)->common.aml_opcode);
		walk_state->opcode = (*op)->common.aml_opcode;

		status = walk_state->ascending_callback(walk_state);
		status = acpi_ps_next_parse_state(walk_state, *op, status);

		status2 = acpi_ps_complete_this_op(walk_state, *op);
		if (ACPI_FAILURE(status2)) {
			return_ACPI_STATUS(status2);
		}

		status = AE_OK;
		break;

	case AE_CTRL_TERMINATE:

		/* Clean up */
		do {
			if (*op) {
				status2 =
				    acpi_ps_complete_this_op(walk_state, *op);
				if (ACPI_FAILURE(status2)) {
					return_ACPI_STATUS(status2);
				}
				status2 = acpi_ds_result_stack_pop(walk_state);
				if (ACPI_FAILURE(status2)) {
					return_ACPI_STATUS(status2);
				}

				acpi_ut_delete_generic_state
				    (acpi_ut_pop_generic_state
				     (&walk_state->control_state));
			}

			acpi_ps_pop_scope(&(walk_state->parser_state), op,
					  &walk_state->arg_types,
					  &walk_state->arg_count);

		} while (*op);

		return_ACPI_STATUS(AE_OK);

	default:		/* All other non-AE_OK status */

		do {
			if (*op) {
				status2 =
				    acpi_ps_complete_this_op(walk_state, *op);
				if (ACPI_FAILURE(status2)) {
					return_ACPI_STATUS(status2);
				}
			}

			acpi_ps_pop_scope(&(walk_state->parser_state), op,
					  &walk_state->arg_types,
					  &walk_state->arg_count);

		} while (*op);

#if 0
		/*
		 * TBD: Cleanup parse ops on error
		 */
		if (*op == NULL) {
			acpi_ps_pop_scope(parser_state, op,
					  &walk_state->arg_types,
					  &walk_state->arg_count);
		}
#endif
		walk_state->prev_op = NULL;
		walk_state->prev_arg_types = walk_state->arg_types;
		return_ACPI_STATUS(status);
	}

	/* This scope complete? */

	if (acpi_ps_has_completed_scope(&(walk_state->parser_state))) {
		acpi_ps_pop_scope(&(walk_state->parser_state), op,
				  &walk_state->arg_types,
				  &walk_state->arg_count);
		ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Popped scope, Op=%p\n", *op));
	} else {
		*op = NULL;
	}

	return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ps_complete_final_op
 *
 * PARAMETERS:  walk_state          - Current state
 *              Op                  - Current Op
 *              Status              - Current parse status before complete last
 *                                    Op
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Complete last Op.
 *
 ******************************************************************************/

static acpi_status
acpi_ps_complete_final_op(struct acpi_walk_state *walk_state,
			  union acpi_parse_object *op, acpi_status status)
{
	acpi_status status2;

	ACPI_FUNCTION_TRACE_PTR(ps_complete_final_op, walk_state);

	/*
	 * Complete the last Op (if not completed), and clear the scope stack.
	 * It is easily possible to end an AML "package" with an unbounded number
	 * of open scopes (such as when several ASL blocks are closed with
	 * sequential closing braces). We want to terminate each one cleanly.
	 */
	ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "AML package complete at Op %p\n",
			  op));
	do {
		if (op) {
			if (walk_state->ascending_callback != NULL) {
				walk_state->op = op;
				walk_state->op_info =
				    acpi_ps_get_opcode_info(op->common.
							    aml_opcode);
				walk_state->opcode = op->common.aml_opcode;

				status =
				    walk_state->ascending_callback(walk_state);
				status =
				    acpi_ps_next_parse_state(walk_state, op,
							     status);
				if (status == AE_CTRL_PENDING) {
					status =
					    acpi_ps_complete_op(walk_state, &op,
								AE_OK);
					if (ACPI_FAILURE(status)) {
						return_ACPI_STATUS(status);
					}
				}

				if (status == AE_CTRL_TERMINATE) {
					status = AE_OK;

					/* Clean up */
					do {
						if (op) {
							status2 =
							    acpi_ps_complete_this_op
							    (walk_state, op);
							if (ACPI_FAILURE
							    (status2)) {
								return_ACPI_STATUS
								    (status2);
							}
						}

						acpi_ps_pop_scope(&
								  (walk_state->
								   parser_state),
								  &op,
								  &walk_state->
								  arg_types,
								  &walk_state->
								  arg_count);

					} while (op);

					return_ACPI_STATUS(status);
				}

				else if (ACPI_FAILURE(status)) {

					/* First error is most important */

					(void)
					    acpi_ps_complete_this_op(walk_state,
								     op);
					return_ACPI_STATUS(status);
				}
			}

			status2 = acpi_ps_complete_this_op(walk_state, op);
			if (ACPI_FAILURE(status2)) {
				return_ACPI_STATUS(status2);
			}
		}

		acpi_ps_pop_scope(&(walk_state->parser_state), &op,
				  &walk_state->arg_types,
				  &walk_state->arg_count);

	} while (op);

	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ps_parse_loop
 *
 * PARAMETERS:  walk_state          - Current state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
 *              a tree of ops.
 *
 ******************************************************************************/

acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)
{
	acpi_status status = AE_OK;
	union acpi_parse_object *op = NULL;	/* current op */
	struct acpi_parse_state *parser_state;
	u8 *aml_op_start = NULL;

	ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state);

	if (walk_state->descending_callback == NULL) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	parser_state = &walk_state->parser_state;
	walk_state->arg_types = 0;

#if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))

	if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {

		/* We are restarting a preempted control method */

		if (acpi_ps_has_completed_scope(parser_state)) {
			/*
			 * We must check if a predicate to an IF or WHILE statement
			 * was just completed
			 */
			if ((parser_state->scope->parse_scope.op) &&
			    ((parser_state->scope->parse_scope.op->common.
			      aml_opcode == AML_IF_OP)
			     || (parser_state->scope->parse_scope.op->common.
				 aml_opcode == AML_WHILE_OP))
			    && (walk_state->control_state)
			    && (walk_state->control_state->common.state ==
				ACPI_CONTROL_PREDICATE_EXECUTING)) {
				/*
				 * A predicate was just completed, get the value of the
				 * predicate and branch based on that value
				 */
				walk_state->op = NULL;
				status =
				    acpi_ds_get_predicate_value(walk_state,
								ACPI_TO_POINTER
								(TRUE));
				if (ACPI_FAILURE(status)
				    && ((status & AE_CODE_MASK) !=
					AE_CODE_CONTROL)) {
					if (status == AE_AML_NO_RETURN_VALUE) {
						ACPI_EXCEPTION((AE_INFO, status,
								"Invoked method did not return a value"));

					}

					ACPI_EXCEPTION((AE_INFO, status,
							"GetPredicate Failed"));
					return_ACPI_STATUS(status);
				}

				status =
				    acpi_ps_next_parse_state(walk_state, op,
							     status);
			}

			acpi_ps_pop_scope(parser_state, &op,
					  &walk_state->arg_types,
					  &walk_state->arg_count);
			ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
					  "Popped scope, Op=%p\n", op));
		} else if (walk_state->prev_op) {

			/* We were in the middle of an op */

			op = walk_state->prev_op;
			walk_state->arg_types = walk_state->prev_arg_types;
		}
	}
#endif

	/* Iterative parsing loop, while there is more AML to process: */

	while ((parser_state->aml < parser_state->aml_end) || (op)) {
		aml_op_start = parser_state->aml;
		if (!op) {
			status =
			    acpi_ps_create_op(walk_state, aml_op_start, &op);
			if (ACPI_FAILURE(status)) {
				if (status == AE_CTRL_PARSE_CONTINUE) {
					continue;
				}

				if (status == AE_CTRL_PARSE_PENDING) {
					status = AE_OK;
				}

				status =
				    acpi_ps_complete_op(walk_state, &op,
							status);
				if (ACPI_FAILURE(status)) {
					return_ACPI_STATUS(status);
				}

				continue;
			}

			op->common.aml_offset = walk_state->aml_offset;

			if (walk_state->op_info) {
				ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
						  "Opcode %4.4X [%s] Op %p Aml %p AmlOffset %5.5X\n",
						  (u32) op->common.aml_opcode,
						  walk_state->op_info->name, op,
						  parser_state->aml,
						  op->common.aml_offset));
			}
		}

		/*
		 * Start arg_count at zero because we don't know if there are
		 * any args yet
		 */
		walk_state->arg_count = 0;

		/* Are there any arguments that must be processed? */

		if (walk_state->arg_types) {

			/* Get arguments */

			status =
			    acpi_ps_get_arguments(walk_state, aml_op_start, op);
			if (ACPI_FAILURE(status)) {
				status =
				    acpi_ps_complete_op(walk_state, &op,
							status);
				if (ACPI_FAILURE(status)) {
					return_ACPI_STATUS(status);
				}

				continue;
			}
		}

		/* Check for arguments that need to be processed */

		if (walk_state->arg_count) {
			/*
			 * There are arguments (complex ones), push Op and
			 * prepare for argument
			 */
			status = acpi_ps_push_scope(parser_state, op,
						    walk_state->arg_types,
						    walk_state->arg_count);
			if (ACPI_FAILURE(status)) {
				status =
				    acpi_ps_complete_op(walk_state, &op,
							status);
				if (ACPI_FAILURE(status)) {
					return_ACPI_STATUS(status);
				}

				continue;
			}

			op = NULL;
			continue;
		}

		/*
		 * All arguments have been processed -- Op is complete,
		 * prepare for next
		 */
		walk_state->op_info =
		    acpi_ps_get_opcode_info(op->common.aml_opcode);
		if (walk_state->op_info->flags & AML_NAMED) {
			if (acpi_gbl_depth) {
				acpi_gbl_depth--;
			}

			if (op->common.aml_opcode == AML_REGION_OP) {
				/*
				 * Skip parsing of control method or opregion body,
				 * because we don't have enough info in the first pass
				 * to parse them correctly.
				 *
				 * Completed parsing an op_region declaration, we now
				 * know the length.
				 */
				op->named.length =
				    (u32) (parser_state->aml - op->named.data);
			}
		}

		if (walk_state->op_info->flags & AML_CREATE) {
			/*
			 * Backup to beginning of create_xXXfield declaration (1 for
			 * Opcode)
			 *
			 * body_length is unknown until we parse the body
			 */
			op->named.length =
			    (u32) (parser_state->aml - op->named.data);
		}

		/* This op complete, notify the dispatcher */

		if (walk_state->ascending_callback != NULL) {
			walk_state->op = op;
			walk_state->opcode = op->common.aml_opcode;

			status = walk_state->ascending_callback(walk_state);
			status =
			    acpi_ps_next_parse_state(walk_state, op, status);
			if (status == AE_CTRL_PENDING) {
				status = AE_OK;
			}
		}

		status = acpi_ps_complete_op(walk_state, &op, status);
		if (ACPI_FAILURE(status)) {
			return_ACPI_STATUS(status);
		}

	}			/* while parser_state->Aml */

	status = acpi_ps_complete_final_op(walk_state, op, status);
	return_ACPI_STATUS(status);
}