// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/*******************************************************************************
 *
 * Module Name: nsnames - Name manipulation and search
 *
 ******************************************************************************/

#include <acpi/acpi.h>
#include "accommon.h"
#include "amlcode.h"
#include "acnamesp.h"

#define _COMPONENT          ACPI_NAMESPACE
ACPI_MODULE_NAME("nsnames")

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_get_external_pathname
 *
 * PARAMETERS:  node            - Namespace node whose pathname is needed
 *
 * RETURN:      Pointer to storage containing the fully qualified name of
 *              the node, In external format (name segments separated by path
 *              separators.)
 *
 * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
 *              for error and debug statements.
 *
 ******************************************************************************/
char *acpi_ns_get_external_pathname(struct acpi_namespace_node *node)
{
        char *name_buffer;

        ACPI_FUNCTION_TRACE_PTR(ns_get_external_pathname, node);

        name_buffer = acpi_ns_get_normalized_pathname(node, FALSE);
        return_PTR(name_buffer);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_get_pathname_length
 *
 * PARAMETERS:  node        - Namespace node
 *
 * RETURN:      Length of path, including prefix
 *
 * DESCRIPTION: Get the length of the pathname string for this node
 *
 ******************************************************************************/

acpi_size acpi_ns_get_pathname_length(struct acpi_namespace_node *node)
{
        acpi_size size;

        /* Validate the Node */

        if (ACPI_GET_DESCRIPTOR_TYPE(node) != ACPI_DESC_TYPE_NAMED) {
                ACPI_ERROR((AE_INFO,
                            "Invalid/cached reference target node: %p, descriptor type %d",
                            node, ACPI_GET_DESCRIPTOR_TYPE(node)));
                return (0);
        }

        size = acpi_ns_build_normalized_path(node, NULL, 0, FALSE);
        return (size);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_handle_to_name
 *
 * PARAMETERS:  target_handle           - Handle of named object whose name is
 *                                        to be found
 *              buffer                  - Where the name is returned
 *
 * RETURN:      Status, Buffer is filled with name if status is AE_OK
 *
 * DESCRIPTION: Build and return a full namespace name
 *
 ******************************************************************************/

acpi_status
acpi_ns_handle_to_name(acpi_handle target_handle, struct acpi_buffer *buffer)
{
        acpi_status status;
        struct acpi_namespace_node *node;
        const char *node_name;

        ACPI_FUNCTION_TRACE_PTR(ns_handle_to_name, target_handle);

        node = acpi_ns_validate_handle(target_handle);
        if (!node) {
                return_ACPI_STATUS(AE_BAD_PARAMETER);
        }

        /* Validate/Allocate/Clear caller buffer */

        status = acpi_ut_initialize_buffer(buffer, ACPI_PATH_SEGMENT_LENGTH);
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        /* Just copy the ACPI name from the Node and zero terminate it */

        node_name = acpi_ut_get_node_name(node);
        ACPI_COPY_NAMESEG(buffer->pointer, node_name);
        ((char *)buffer->pointer)[ACPI_NAMESEG_SIZE] = 0;

        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%4.4s\n", (char *)buffer->pointer));
        return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_handle_to_pathname
 *
 * PARAMETERS:  target_handle           - Handle of named object whose name is
 *                                        to be found
 *              buffer                  - Where the pathname is returned
 *              no_trailing             - Remove trailing '_' for each name
 *                                        segment
 *
 * RETURN:      Status, Buffer is filled with pathname if status is AE_OK
 *
 * DESCRIPTION: Build and return a full namespace pathname
 *
 ******************************************************************************/

acpi_status
acpi_ns_handle_to_pathname(acpi_handle target_handle,
                           struct acpi_buffer *buffer, u8 no_trailing)
{
        acpi_status status;
        struct acpi_namespace_node *node;
        acpi_size required_size;

        ACPI_FUNCTION_TRACE_PTR(ns_handle_to_pathname, target_handle);

        node = acpi_ns_validate_handle(target_handle);
        if (!node) {
                return_ACPI_STATUS(AE_BAD_PARAMETER);
        }

        /* Determine size required for the caller buffer */

        required_size =
            acpi_ns_build_normalized_path(node, NULL, 0, no_trailing);
        if (!required_size) {
                return_ACPI_STATUS(AE_BAD_PARAMETER);
        }

        /* Validate/Allocate/Clear caller buffer */

        status = acpi_ut_initialize_buffer(buffer, required_size);
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        /* Build the path in the caller buffer */

        (void)acpi_ns_build_normalized_path(node, buffer->pointer,
                                            (u32)required_size, no_trailing);

        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%s [%X]\n",
                          (char *)buffer->pointer, (u32) required_size));
        return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_build_normalized_path
 *
 * PARAMETERS:  node        - Namespace node
 *              full_path   - Where the path name is returned
 *              path_size   - Size of returned path name buffer
 *              no_trailing - Remove trailing '_' from each name segment
 *
 * RETURN:      Return 1 if the AML path is empty, otherwise returning (length
 *              of pathname + 1) which means the 'FullPath' contains a trailing
 *              null.
 *
 * DESCRIPTION: Build and return a full namespace pathname.
 *              Note that if the size of 'FullPath' isn't large enough to
 *              contain the namespace node's path name, the actual required
 *              buffer length is returned, and it should be greater than
 *              'PathSize'. So callers are able to check the returning value
 *              to determine the buffer size of 'FullPath'.
 *
 ******************************************************************************/

u32
acpi_ns_build_normalized_path(struct acpi_namespace_node *node,
                              char *full_path, u32 path_size, u8 no_trailing)
{
        u32 length = 0, i;
        char name[ACPI_NAMESEG_SIZE] ACPI_NONSTRING;
        u8 do_no_trailing;
        char c, *left, *right;
        struct acpi_namespace_node *next_node;

        ACPI_FUNCTION_TRACE_PTR(ns_build_normalized_path, node);

#define ACPI_PATH_PUT8(path, size, byte, length)    \
        do {                                            \
                if ((length) < (size))                      \
                {                                           \
                        (path)[(length)] = (byte);              \
                }                                           \
                (length)++;                                 \
        } while (0)

        /*
         * Make sure the path_size is correct, so that we don't need to
         * validate both full_path and path_size.
         */
        if (!full_path) {
                path_size = 0;
        }

        if (!node) {
                goto build_trailing_null;
        }

        next_node = node;
        while (next_node && next_node != acpi_gbl_root_node) {
                if (next_node != node) {
                        ACPI_PATH_PUT8(full_path, path_size,
                                       AML_DUAL_NAME_PREFIX, length);
                }

                ACPI_MOVE_32_TO_32(name, &next_node->name);
                do_no_trailing = no_trailing;
                for (i = 0; i < 4; i++) {
                        c = name[4 - i - 1];
                        if (do_no_trailing && c != '_') {
                                do_no_trailing = FALSE;
                        }
                        if (!do_no_trailing) {
                                ACPI_PATH_PUT8(full_path, path_size, c, length);
                        }
                }

                next_node = next_node->parent;
        }

        ACPI_PATH_PUT8(full_path, path_size, AML_ROOT_PREFIX, length);

        /* Reverse the path string */

        if (length <= path_size) {
                left = full_path;
                right = full_path + length - 1;

                while (left < right) {
                        c = *left;
                        *left++ = *right;
                        *right-- = c;
                }
        }

        /* Append the trailing null */

build_trailing_null:
        ACPI_PATH_PUT8(full_path, path_size, '\0', length);

#undef ACPI_PATH_PUT8

        return_UINT32(length);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_get_normalized_pathname
 *
 * PARAMETERS:  node            - Namespace node whose pathname is needed
 *              no_trailing     - Remove trailing '_' from each name segment
 *
 * RETURN:      Pointer to storage containing the fully qualified name of
 *              the node, In external format (name segments separated by path
 *              separators.)
 *
 * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
 *              for error and debug statements. All trailing '_' will be
 *              removed from the full pathname if 'NoTrailing' is specified..
 *
 ******************************************************************************/

char *acpi_ns_get_normalized_pathname(struct acpi_namespace_node *node,
                                      u8 no_trailing)
{
        char *name_buffer;
        acpi_size size;

        ACPI_FUNCTION_TRACE_PTR(ns_get_normalized_pathname, node);

        /* Calculate required buffer size based on depth below root */

        size = acpi_ns_build_normalized_path(node, NULL, 0, no_trailing);
        if (!size) {
                return_PTR(NULL);
        }

        /* Allocate a buffer to be returned to caller */

        name_buffer = ACPI_ALLOCATE_ZEROED(size);
        if (!name_buffer) {
                ACPI_ERROR((AE_INFO, "Could not allocate %u bytes", (u32)size));
                return_PTR(NULL);
        }

        /* Build the path in the allocated buffer */

        (void)acpi_ns_build_normalized_path(node, name_buffer, (u32)size,
                                            no_trailing);

        ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES, "%s: Path \"%s\"\n",
                              ACPI_GET_FUNCTION_NAME, name_buffer));

        return_PTR(name_buffer);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_build_prefixed_pathname
 *
 * PARAMETERS:  prefix_scope        - Scope/Path that prefixes the internal path
 *              internal_path       - Name or path of the namespace node
 *
 * RETURN:      None
 *
 * DESCRIPTION: Construct a fully qualified pathname from a concatenation of:
 *              1) Path associated with the prefix_scope namespace node
 *              2) External path representation of the Internal path
 *
 ******************************************************************************/

char *acpi_ns_build_prefixed_pathname(union acpi_generic_state *prefix_scope,
                                      const char *internal_path)
{
        acpi_status status;
        char *full_path = NULL;
        char *external_path = NULL;
        char *prefix_path = NULL;
        acpi_size prefix_path_length = 0;

        /* If there is a prefix, get the pathname to it */

        if (prefix_scope && prefix_scope->scope.node) {
                prefix_path =
                    acpi_ns_get_normalized_pathname(prefix_scope->scope.node,
                                                    TRUE);
                if (prefix_path) {
                        prefix_path_length = strlen(prefix_path);
                }
        }

        status = acpi_ns_externalize_name(ACPI_UINT32_MAX, internal_path,
                                          NULL, &external_path);
        if (ACPI_FAILURE(status)) {
                goto cleanup;
        }

        /* Merge the prefix path and the path. 2 is for one dot and trailing null */

        full_path =
            ACPI_ALLOCATE_ZEROED(prefix_path_length + strlen(external_path) +
                                 2);
        if (!full_path) {
                goto cleanup;
        }

        /* Don't merge if the External path is already fully qualified */

        if (prefix_path && (*external_path != '\\') && (*external_path != '^')) {
                strcat(full_path, prefix_path);
                if (prefix_path[1]) {
                        strcat(full_path, ".");
                }
        }

        acpi_ns_normalize_pathname(external_path);
        strcat(full_path, external_path);

cleanup:
        if (prefix_path) {
                ACPI_FREE(prefix_path);
        }
        if (external_path) {
                ACPI_FREE(external_path);
        }

        return (full_path);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_normalize_pathname
 *
 * PARAMETERS:  original_path       - Path to be normalized, in External format
 *
 * RETURN:      The original path is processed in-place
 *
 * DESCRIPTION: Remove trailing underscores from each element of a path.
 *
 *              For example:  \A___.B___.C___ becomes \A.B.C
 *
 ******************************************************************************/

void acpi_ns_normalize_pathname(char *original_path)
{
        char *input_path = original_path;
        char *new_path_buffer;
        char *new_path;
        u32 i;

        /* Allocate a temp buffer in which to construct the new path */

        new_path_buffer = ACPI_ALLOCATE_ZEROED(strlen(input_path) + 1);
        new_path = new_path_buffer;
        if (!new_path_buffer) {
                return;
        }

        /* Special characters may appear at the beginning of the path */

        if (*input_path == '\\') {
                *new_path = *input_path;
                new_path++;
                input_path++;
        }

        while (*input_path == '^') {
                *new_path = *input_path;
                new_path++;
                input_path++;
        }

        /* Remainder of the path */

        while (*input_path) {

                /* Do one nameseg at a time */

                for (i = 0; (i < ACPI_NAMESEG_SIZE) && *input_path; i++) {
                        if ((i == 0) || (*input_path != '_')) { /* First char is allowed to be underscore */
                                *new_path = *input_path;
                                new_path++;
                        }

                        input_path++;
                }

                /* Dot means that there are more namesegs to come */

                if (*input_path == '.') {
                        *new_path = *input_path;
                        new_path++;
                        input_path++;
                }
        }

        *new_path = 0;
        strcpy(original_path, new_path_buffer);
        ACPI_FREE(new_path_buffer);
}