// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
 *
 * Module Name: pstree - Parser op tree manipulation/traversal/search
 *
 * Copyright (C) 2000 - 2025, Intel Corp.
 *
 *****************************************************************************/

#include <acpi/acpi.h>
#include "accommon.h"
#include "acparser.h"
#include "amlcode.h"
#include "acconvert.h"

#define _COMPONENT          ACPI_PARSER
ACPI_MODULE_NAME("pstree")

/* Local prototypes */
#ifdef ACPI_OBSOLETE_FUNCTIONS
union acpi_parse_object *acpi_ps_get_child(union acpi_parse_object *op);
#endif

/*******************************************************************************
 *
 * FUNCTION:    acpi_ps_get_arg
 *
 * PARAMETERS:  op              - Get an argument for this op
 *              argn            - Nth argument to get
 *
 * RETURN:      The argument (as an Op object). NULL if argument does not exist
 *
 * DESCRIPTION: Get the specified op's argument.
 *
 ******************************************************************************/

union acpi_parse_object *acpi_ps_get_arg(union acpi_parse_object *op, u32 argn)
{
        union acpi_parse_object *arg = NULL;
        const struct acpi_opcode_info *op_info;

        ACPI_FUNCTION_ENTRY();

/*
        if (Op->Common.aml_opcode == AML_INT_CONNECTION_OP)
        {
                return (Op->Common.Value.Arg);
        }
*/
        /* Get the info structure for this opcode */

        op_info = acpi_ps_get_opcode_info(op->common.aml_opcode);
        if (op_info->class == AML_CLASS_UNKNOWN) {

                /* Invalid opcode or ASCII character */

                return (NULL);
        }

        /* Check if this opcode requires argument sub-objects */

        if (!(op_info->flags & AML_HAS_ARGS)) {

                /* Has no linked argument objects */

                return (NULL);
        }

        /* Get the requested argument object */

        arg = op->common.value.arg;
        while (arg && argn) {
                argn--;
                arg = arg->common.next;
        }

        return (arg);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ps_append_arg
 *
 * PARAMETERS:  op              - Append an argument to this Op.
 *              arg             - Argument Op to append
 *
 * RETURN:      None.
 *
 * DESCRIPTION: Append an argument to an op's argument list (a NULL arg is OK)
 *
 ******************************************************************************/

void
acpi_ps_append_arg(union acpi_parse_object *op, union acpi_parse_object *arg)
{
        union acpi_parse_object *prev_arg;
        const struct acpi_opcode_info *op_info;

        ACPI_FUNCTION_TRACE(ps_append_arg);

        if (!op) {
                return_VOID;
        }

        /* Get the info structure for this opcode */

        op_info = acpi_ps_get_opcode_info(op->common.aml_opcode);
        if (op_info->class == AML_CLASS_UNKNOWN) {

                /* Invalid opcode */

                ACPI_ERROR((AE_INFO, "Invalid AML Opcode: 0x%2.2X",
                            op->common.aml_opcode));
                return_VOID;
        }

        /* Check if this opcode requires argument sub-objects */

        if (!(op_info->flags & AML_HAS_ARGS)) {

                /* Has no linked argument objects */

                return_VOID;
        }

        /* Append the argument to the linked argument list */

        if (op->common.value.arg) {

                /* Append to existing argument list */

                prev_arg = op->common.value.arg;
                while (prev_arg->common.next) {
                        prev_arg = prev_arg->common.next;
                }
                prev_arg->common.next = arg;
        } else {
                /* No argument list, this will be the first argument */

                op->common.value.arg = arg;
        }

        /* Set the parent in this arg and any args linked after it */

        while (arg) {
                arg->common.parent = op;
                arg = arg->common.next;

                op->common.arg_list_length++;
        }

        return_VOID;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ps_get_depth_next
 *
 * PARAMETERS:  origin          - Root of subtree to search
 *              op              - Last (previous) Op that was found
 *
 * RETURN:      Next Op found in the search.
 *
 * DESCRIPTION: Get next op in tree (walking the tree in depth-first order)
 *              Return NULL when reaching "origin" or when walking up from root
 *
 ******************************************************************************/

union acpi_parse_object *acpi_ps_get_depth_next(union acpi_parse_object *origin,
                                                union acpi_parse_object *op)
{
        union acpi_parse_object *next = NULL;
        union acpi_parse_object *parent;
        union acpi_parse_object *arg;

        ACPI_FUNCTION_ENTRY();

        if (!op) {
                return (NULL);
        }

        /* Look for an argument or child */

        next = acpi_ps_get_arg(op, 0);
        if (next) {
                ASL_CV_LABEL_FILENODE(next);
                return (next);
        }

        /* Look for a sibling */

        next = op->common.next;
        if (next) {
                ASL_CV_LABEL_FILENODE(next);
                return (next);
        }

        /* Look for a sibling of parent */

        parent = op->common.parent;

        while (parent) {
                arg = acpi_ps_get_arg(parent, 0);
                while (arg && (arg != origin) && (arg != op)) {

                        ASL_CV_LABEL_FILENODE(arg);
                        arg = arg->common.next;
                }

                if (arg == origin) {

                        /* Reached parent of origin, end search */

                        return (NULL);
                }

                if (parent->common.next) {

                        /* Found sibling of parent */

                        ASL_CV_LABEL_FILENODE(parent->common.next);
                        return (parent->common.next);
                }

                op = parent;
                parent = parent->common.parent;
        }

        ASL_CV_LABEL_FILENODE(next);
        return (next);
}

#ifdef ACPI_OBSOLETE_FUNCTIONS
/*******************************************************************************
 *
 * FUNCTION:    acpi_ps_get_child
 *
 * PARAMETERS:  op              - Get the child of this Op
 *
 * RETURN:      Child Op, Null if none is found.
 *
 * DESCRIPTION: Get op's children or NULL if none
 *
 ******************************************************************************/

union acpi_parse_object *acpi_ps_get_child(union acpi_parse_object *op)
{
        union acpi_parse_object *child = NULL;

        ACPI_FUNCTION_ENTRY();

        switch (op->common.aml_opcode) {
        case AML_SCOPE_OP:
        case AML_ELSE_OP:
        case AML_DEVICE_OP:
        case AML_THERMAL_ZONE_OP:
        case AML_INT_METHODCALL_OP:

                child = acpi_ps_get_arg(op, 0);
                break;

        case AML_BUFFER_OP:
        case AML_PACKAGE_OP:
        case AML_VARIABLE_PACKAGE_OP:
        case AML_METHOD_OP:
        case AML_IF_OP:
        case AML_WHILE_OP:
        case AML_FIELD_OP:

                child = acpi_ps_get_arg(op, 1);
                break;

        case AML_POWER_RESOURCE_OP:
        case AML_INDEX_FIELD_OP:

                child = acpi_ps_get_arg(op, 2);
                break;

        case AML_PROCESSOR_OP:
        case AML_BANK_FIELD_OP:

                child = acpi_ps_get_arg(op, 3);
                break;

        default:

                /* All others have no children */

                break;
        }

        return (child);
}
#endif