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linux-stable-rt/drivers/acpi/utilities/utmisc.c

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/*******************************************************************************
*
* Module Name: utmisc - common utility procedures
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2006, R. Byron Moore
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
* 3. Neither the names of the above-listed copyright holders nor the names
* of any contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*/
#include <acpi/acpi.h>
#include <acpi/acnamesp.h>
#define _COMPONENT ACPI_UTILITIES
ACPI_MODULE_NAME("utmisc")
/*******************************************************************************
*
* FUNCTION: acpi_ut_allocate_owner_id
*
* PARAMETERS: owner_id - Where the new owner ID is returned
*
* RETURN: Status
*
* DESCRIPTION: Allocate a table or method owner ID. The owner ID is used to
* track objects created by the table or method, to be deleted
* when the method exits or the table is unloaded.
*
******************************************************************************/
acpi_status acpi_ut_allocate_owner_id(acpi_owner_id * owner_id)
{
acpi_native_uint i;
acpi_native_uint j;
acpi_native_uint k;
acpi_status status;
ACPI_FUNCTION_TRACE("ut_allocate_owner_id");
/* Guard against multiple allocations of ID to the same location */
if (*owner_id) {
ACPI_ERROR((AE_INFO, "Owner ID [%2.2X] already exists",
*owner_id));
return_ACPI_STATUS(AE_ALREADY_EXISTS);
}
/* Mutex for the global ID mask */
status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* Find a free owner ID, cycle through all possible IDs on repeated
* allocations. (ACPI_NUM_OWNERID_MASKS + 1) because first index may have
* to be scanned twice.
*/
for (i = 0, j = acpi_gbl_last_owner_id_index;
i < (ACPI_NUM_OWNERID_MASKS + 1); i++, j++) {
if (j >= ACPI_NUM_OWNERID_MASKS) {
j = 0; /* Wraparound to start of mask array */
}
for (k = acpi_gbl_next_owner_id_offset; k < 32; k++) {
if (acpi_gbl_owner_id_mask[j] == ACPI_UINT32_MAX) {
/* There are no free IDs in this mask */
break;
}
if (!(acpi_gbl_owner_id_mask[j] & (1 << k))) {
/*
* Found a free ID. The actual ID is the bit index plus one,
* making zero an invalid Owner ID. Save this as the last ID
* allocated and update the global ID mask.
*/
acpi_gbl_owner_id_mask[j] |= (1 << k);
acpi_gbl_last_owner_id_index = (u8) j;
acpi_gbl_next_owner_id_offset = (u8) (k + 1);
/*
* Construct encoded ID from the index and bit position
*
* Note: Last [j].k (bit 255) is never used and is marked
* permanently allocated (prevents +1 overflow)
*/
*owner_id =
(acpi_owner_id) ((k + 1) + ACPI_MUL_32(j));
ACPI_DEBUG_PRINT((ACPI_DB_VALUES,
"Allocated owner_id: %2.2X\n",
(unsigned int)*owner_id));
goto exit;
}
}
acpi_gbl_next_owner_id_offset = 0;
}
/*
* All owner_ids have been allocated. This typically should
* not happen since the IDs are reused after deallocation. The IDs are
* allocated upon table load (one per table) and method execution, and
* they are released when a table is unloaded or a method completes
* execution.
*
* If this error happens, there may be very deep nesting of invoked control
* methods, or there may be a bug where the IDs are not released.
*/
status = AE_OWNER_ID_LIMIT;
ACPI_ERROR((AE_INFO,
"Could not allocate new owner_id (255 max), AE_OWNER_ID_LIMIT"));
exit:
(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_release_owner_id
*
* PARAMETERS: owner_id_ptr - Pointer to a previously allocated owner_iD
*
* RETURN: None. No error is returned because we are either exiting a
* control method or unloading a table. Either way, we would
* ignore any error anyway.
*
* DESCRIPTION: Release a table or method owner ID. Valid IDs are 1 - 255
*
******************************************************************************/
void acpi_ut_release_owner_id(acpi_owner_id * owner_id_ptr)
{
acpi_owner_id owner_id = *owner_id_ptr;
acpi_status status;
acpi_native_uint index;
u32 bit;
ACPI_FUNCTION_TRACE_U32("ut_release_owner_id", owner_id);
/* Always clear the input owner_id (zero is an invalid ID) */
*owner_id_ptr = 0;
/* Zero is not a valid owner_iD */
if (owner_id == 0) {
ACPI_ERROR((AE_INFO, "Invalid owner_id: %2.2X", owner_id));
return_VOID;
}
/* Mutex for the global ID mask */
status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
if (ACPI_FAILURE(status)) {
return_VOID;
}
/* Normalize the ID to zero */
owner_id--;
/* Decode ID to index/offset pair */
index = ACPI_DIV_32(owner_id);
bit = 1 << ACPI_MOD_32(owner_id);
/* Free the owner ID only if it is valid */
if (acpi_gbl_owner_id_mask[index] & bit) {
acpi_gbl_owner_id_mask[index] ^= bit;
} else {
ACPI_ERROR((AE_INFO,
"Release of non-allocated owner_id: %2.2X",
owner_id + 1));
}
(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
return_VOID;
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_strupr (strupr)
*
* PARAMETERS: src_string - The source string to convert
*
* RETURN: None
*
* DESCRIPTION: Convert string to uppercase
*
* NOTE: This is not a POSIX function, so it appears here, not in utclib.c
*
******************************************************************************/
void acpi_ut_strupr(char *src_string)
{
char *string;
ACPI_FUNCTION_ENTRY();
if (!src_string) {
return;
}
/* Walk entire string, uppercasing the letters */
for (string = src_string; *string; string++) {
*string = (char)ACPI_TOUPPER(*string);
}
return;
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_print_string
*
* PARAMETERS: String - Null terminated ASCII string
* max_length - Maximum output length
*
* RETURN: None
*
* DESCRIPTION: Dump an ASCII string with support for ACPI-defined escape
* sequences.
*
******************************************************************************/
void acpi_ut_print_string(char *string, u8 max_length)
{
u32 i;
if (!string) {
acpi_os_printf("<\"NULL STRING PTR\">");
return;
}
acpi_os_printf("\"");
for (i = 0; string[i] && (i < max_length); i++) {
/* Escape sequences */
switch (string[i]) {
case 0x07:
acpi_os_printf("\\a"); /* BELL */
break;
case 0x08:
acpi_os_printf("\\b"); /* BACKSPACE */
break;
case 0x0C:
acpi_os_printf("\\f"); /* FORMFEED */
break;
case 0x0A:
acpi_os_printf("\\n"); /* LINEFEED */
break;
case 0x0D:
acpi_os_printf("\\r"); /* CARRIAGE RETURN */
break;
case 0x09:
acpi_os_printf("\\t"); /* HORIZONTAL TAB */
break;
case 0x0B:
acpi_os_printf("\\v"); /* VERTICAL TAB */
break;
case '\'': /* Single Quote */
case '\"': /* Double Quote */
case '\\': /* Backslash */
acpi_os_printf("\\%c", (int)string[i]);
break;
default:
/* Check for printable character or hex escape */
if (ACPI_IS_PRINT(string[i])) {
/* This is a normal character */
acpi_os_printf("%c", (int)string[i]);
} else {
/* All others will be Hex escapes */
acpi_os_printf("\\x%2.2X", (s32) string[i]);
}
break;
}
}
acpi_os_printf("\"");
if (i == max_length && string[i]) {
acpi_os_printf("...");
}
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_dword_byte_swap
*
* PARAMETERS: Value - Value to be converted
*
* RETURN: u32 integer with bytes swapped
*
* DESCRIPTION: Convert a 32-bit value to big-endian (swap the bytes)
*
******************************************************************************/
u32 acpi_ut_dword_byte_swap(u32 value)
{
union {
u32 value;
u8 bytes[4];
} out;
union {
u32 value;
u8 bytes[4];
} in;
ACPI_FUNCTION_ENTRY();
in.value = value;
out.bytes[0] = in.bytes[3];
out.bytes[1] = in.bytes[2];
out.bytes[2] = in.bytes[1];
out.bytes[3] = in.bytes[0];
return (out.value);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_set_integer_width
*
* PARAMETERS: Revision From DSDT header
*
* RETURN: None
*
* DESCRIPTION: Set the global integer bit width based upon the revision
* of the DSDT. For Revision 1 and 0, Integers are 32 bits.
* For Revision 2 and above, Integers are 64 bits. Yes, this
* makes a difference.
*
******************************************************************************/
void acpi_ut_set_integer_width(u8 revision)
{
if (revision <= 1) {
acpi_gbl_integer_bit_width = 32;
acpi_gbl_integer_nybble_width = 8;
acpi_gbl_integer_byte_width = 4;
} else {
acpi_gbl_integer_bit_width = 64;
acpi_gbl_integer_nybble_width = 16;
acpi_gbl_integer_byte_width = 8;
}
}
#ifdef ACPI_DEBUG_OUTPUT
/*******************************************************************************
*
* FUNCTION: acpi_ut_display_init_pathname
*
* PARAMETERS: Type - Object type of the node
* obj_handle - Handle whose pathname will be displayed
* Path - Additional path string to be appended.
* (NULL if no extra path)
*
* RETURN: acpi_status
*
* DESCRIPTION: Display full pathname of an object, DEBUG ONLY
*
******************************************************************************/
void
acpi_ut_display_init_pathname(u8 type,
struct acpi_namespace_node *obj_handle,
char *path)
{
acpi_status status;
struct acpi_buffer buffer;
ACPI_FUNCTION_ENTRY();
/* Only print the path if the appropriate debug level is enabled */
if (!(acpi_dbg_level & ACPI_LV_INIT_NAMES)) {
return;
}
/* Get the full pathname to the node */
buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
status = acpi_ns_handle_to_pathname(obj_handle, &buffer);
if (ACPI_FAILURE(status)) {
return;
}
/* Print what we're doing */
switch (type) {
case ACPI_TYPE_METHOD:
acpi_os_printf("Executing ");
break;
default:
acpi_os_printf("Initializing ");
break;
}
/* Print the object type and pathname */
acpi_os_printf("%-12s %s",
acpi_ut_get_type_name(type), (char *)buffer.pointer);
/* Extra path is used to append names like _STA, _INI, etc. */
if (path) {
acpi_os_printf(".%s", path);
}
acpi_os_printf("\n");
ACPI_MEM_FREE(buffer.pointer);
}
#endif
/*******************************************************************************
*
* FUNCTION: acpi_ut_valid_acpi_name
*
* PARAMETERS: Name - The name to be examined
*
* RETURN: TRUE if the name is valid, FALSE otherwise
*
* DESCRIPTION: Check for a valid ACPI name. Each character must be one of:
* 1) Upper case alpha
* 2) numeric
* 3) underscore
*
******************************************************************************/
u8 acpi_ut_valid_acpi_name(u32 name)
{
char *name_ptr = (char *)&name;
char character;
acpi_native_uint i;
ACPI_FUNCTION_ENTRY();
for (i = 0; i < ACPI_NAME_SIZE; i++) {
character = *name_ptr;
name_ptr++;
if (!((character == '_') ||
(character >= 'A' && character <= 'Z') ||
(character >= '0' && character <= '9'))) {
return (FALSE);
}
}
return (TRUE);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_valid_acpi_character
*
* PARAMETERS: Character - The character to be examined
*
* RETURN: 1 if Character may appear in a name, else 0
*
* DESCRIPTION: Check for a printable character
*
******************************************************************************/
u8 acpi_ut_valid_acpi_character(char character)
{
ACPI_FUNCTION_ENTRY();
return ((u8) ((character == '_') ||
(character >= 'A' && character <= 'Z') ||
(character >= '0' && character <= '9')));
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_strtoul64
*
* PARAMETERS: String - Null terminated string
* Base - Radix of the string: 10, 16, or ACPI_ANY_BASE
* ret_integer - Where the converted integer is returned
*
* RETURN: Status and Converted value
*
* DESCRIPTION: Convert a string into an unsigned value.
* NOTE: Does not support Octal strings, not needed.
*
******************************************************************************/
acpi_status
acpi_ut_strtoul64(char *string, u32 base, acpi_integer * ret_integer)
{
u32 this_digit = 0;
acpi_integer return_value = 0;
acpi_integer quotient;
ACPI_FUNCTION_TRACE("ut_stroul64");
if ((!string) || !(*string)) {
goto error_exit;
}
switch (base) {
case ACPI_ANY_BASE:
case 10:
case 16:
break;
default:
/* Invalid Base */
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Skip over any white space in the buffer */
while (ACPI_IS_SPACE(*string) || *string == '\t') {
string++;
}
/*
* If the input parameter Base is zero, then we need to
* determine if it is decimal or hexadecimal:
*/
if (base == 0) {
if ((*string == '0') && (ACPI_TOLOWER(*(string + 1)) == 'x')) {
base = 16;
string += 2;
} else {
base = 10;
}
}
/*
* For hexadecimal base, skip over the leading
* 0 or 0x, if they are present.
*/
if ((base == 16) &&
(*string == '0') && (ACPI_TOLOWER(*(string + 1)) == 'x')) {
string += 2;
}
/* Any string left? */
if (!(*string)) {
goto error_exit;
}
/* Main loop: convert the string to a 64-bit integer */
while (*string) {
if (ACPI_IS_DIGIT(*string)) {
/* Convert ASCII 0-9 to Decimal value */
this_digit = ((u8) * string) - '0';
} else {
if (base == 10) {
/* Digit is out of range */
goto error_exit;
}
this_digit = (u8) ACPI_TOUPPER(*string);
if (ACPI_IS_XDIGIT((char)this_digit)) {
/* Convert ASCII Hex char to value */
this_digit = this_digit - 'A' + 10;
} else {
/*
* We allow non-hex chars, just stop now, same as end-of-string.
* See ACPI spec, string-to-integer conversion.
*/
break;
}
}
/* Divide the digit into the correct position */
(void)
acpi_ut_short_divide((ACPI_INTEGER_MAX -
(acpi_integer) this_digit), base,
&quotient, NULL);
if (return_value > quotient) {
goto error_exit;
}
return_value *= base;
return_value += this_digit;
string++;
}
/* All done, normal exit */
*ret_integer = return_value;
return_ACPI_STATUS(AE_OK);
error_exit:
/* Base was set/validated above */
if (base == 10) {
return_ACPI_STATUS(AE_BAD_DECIMAL_CONSTANT);
} else {
return_ACPI_STATUS(AE_BAD_HEX_CONSTANT);
}
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_create_update_state_and_push
*
* PARAMETERS: Object - Object to be added to the new state
* Action - Increment/Decrement
* state_list - List the state will be added to
*
* RETURN: Status
*
* DESCRIPTION: Create a new state and push it
*
******************************************************************************/
acpi_status
acpi_ut_create_update_state_and_push(union acpi_operand_object *object,
u16 action,
union acpi_generic_state **state_list)
{
union acpi_generic_state *state;
ACPI_FUNCTION_ENTRY();
/* Ignore null objects; these are expected */
if (!object) {
return (AE_OK);
}
state = acpi_ut_create_update_state(object, action);
if (!state) {
return (AE_NO_MEMORY);
}
acpi_ut_push_generic_state(state_list, state);
return (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_walk_package_tree
*
* PARAMETERS: source_object - The package to walk
* target_object - Target object (if package is being copied)
* walk_callback - Called once for each package element
* Context - Passed to the callback function
*
* RETURN: Status
*
* DESCRIPTION: Walk through a package
*
******************************************************************************/
acpi_status
acpi_ut_walk_package_tree(union acpi_operand_object * source_object,
void *target_object,
acpi_pkg_callback walk_callback, void *context)
{
acpi_status status = AE_OK;
union acpi_generic_state *state_list = NULL;
union acpi_generic_state *state;
u32 this_index;
union acpi_operand_object *this_source_obj;
ACPI_FUNCTION_TRACE("ut_walk_package_tree");
state = acpi_ut_create_pkg_state(source_object, target_object, 0);
if (!state) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
while (state) {
/* Get one element of the package */
this_index = state->pkg.index;
this_source_obj = (union acpi_operand_object *)
state->pkg.source_object->package.elements[this_index];
/*
* Check for:
* 1) An uninitialized package element. It is completely
* legal to declare a package and leave it uninitialized
* 2) Not an internal object - can be a namespace node instead
* 3) Any type other than a package. Packages are handled in else
* case below.
*/
if ((!this_source_obj) ||
(ACPI_GET_DESCRIPTOR_TYPE(this_source_obj) !=
ACPI_DESC_TYPE_OPERAND)
|| (ACPI_GET_OBJECT_TYPE(this_source_obj) !=
ACPI_TYPE_PACKAGE)) {
status =
walk_callback(ACPI_COPY_TYPE_SIMPLE,
this_source_obj, state, context);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
state->pkg.index++;
while (state->pkg.index >=
state->pkg.source_object->package.count) {
/*
* We've handled all of the objects at this level, This means
* that we have just completed a package. That package may
* have contained one or more packages itself.
*
* Delete this state and pop the previous state (package).
*/
acpi_ut_delete_generic_state(state);
state = acpi_ut_pop_generic_state(&state_list);
/* Finished when there are no more states */
if (!state) {
/*
* We have handled all of the objects in the top level
* package just add the length of the package objects
* and exit
*/
return_ACPI_STATUS(AE_OK);
}
/*
* Go back up a level and move the index past the just
* completed package object.
*/
state->pkg.index++;
}
} else {
/* This is a subobject of type package */
status =
walk_callback(ACPI_COPY_TYPE_PACKAGE,
this_source_obj, state, context);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* Push the current state and create a new one
* The callback above returned a new target package object.
*/
acpi_ut_push_generic_state(&state_list, state);
state = acpi_ut_create_pkg_state(this_source_obj,
state->pkg.
this_target_obj, 0);
if (!state) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
}
}
/* We should never get here */
return_ACPI_STATUS(AE_AML_INTERNAL);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_generate_checksum
*
* PARAMETERS: Buffer - Buffer to be scanned
* Length - number of bytes to examine
*
* RETURN: The generated checksum
*
* DESCRIPTION: Generate a checksum on a raw buffer
*
******************************************************************************/
u8 acpi_ut_generate_checksum(u8 * buffer, u32 length)
{
u32 i;
signed char sum = 0;
for (i = 0; i < length; i++) {
sum = (signed char)(sum + buffer[i]);
}
return ((u8) (0 - sum));
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_error, acpi_ut_warning, acpi_ut_info
*
* PARAMETERS: module_name - Caller's module name (for error output)
* line_number - Caller's line number (for error output)
* Format - Printf format string + additional args
*
* RETURN: None
*
* DESCRIPTION: Print message with module/line/version info
*
******************************************************************************/
void ACPI_INTERNAL_VAR_XFACE
acpi_ut_error(char *module_name, u32 line_number, char *format, ...)
{
va_list args;
acpi_os_printf("ACPI Error (%s-%04d): ", module_name, line_number);
va_start(args, format);
acpi_os_vprintf(format, args);
acpi_os_printf(" [%X]\n", ACPI_CA_VERSION);
}
void ACPI_INTERNAL_VAR_XFACE
acpi_ut_exception(char *module_name,
u32 line_number, acpi_status status, char *format, ...)
{
va_list args;
acpi_os_printf("ACPI Exception (%s-%04d): %s, ", module_name,
line_number, acpi_format_exception(status));
va_start(args, format);
acpi_os_vprintf(format, args);
acpi_os_printf(" [%X]\n", ACPI_CA_VERSION);
}
void ACPI_INTERNAL_VAR_XFACE
acpi_ut_warning(char *module_name, u32 line_number, char *format, ...)
{
va_list args;
acpi_os_printf("ACPI Warning (%s-%04d): ", module_name, line_number);
va_start(args, format);
acpi_os_vprintf(format, args);
acpi_os_printf(" [%X]\n", ACPI_CA_VERSION);
}
void ACPI_INTERNAL_VAR_XFACE
acpi_ut_info(char *module_name, u32 line_number, char *format, ...)
{
va_list args;
acpi_os_printf("ACPI (%s-%04d): ", module_name, line_number);
va_start(args, format);
acpi_os_vprintf(format, args);
acpi_os_printf(" [%X]\n", ACPI_CA_VERSION);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_report_error, Warning, Info
*
* PARAMETERS: module_name - Caller's module name (for error output)
* line_number - Caller's line number (for error output)
*
* RETURN: None
*
* DESCRIPTION: Print error message
*
* Note: Legacy only, should be removed when no longer used by drivers.
*
******************************************************************************/
void acpi_ut_report_error(char *module_name, u32 line_number)
{
acpi_os_printf("ACPI Error (%s-%04d): ", module_name, line_number);
}
void acpi_ut_report_warning(char *module_name, u32 line_number)
{
acpi_os_printf("ACPI Warning (%s-%04d): ", module_name, line_number);
}
void acpi_ut_report_info(char *module_name, u32 line_number)
{
acpi_os_printf("ACPI (%s-%04d): ", module_name, line_number);
}
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