/****************************************************************************** * * Module Name: dswstate - Dispatcher parse tree walk management routines * *****************************************************************************/ /* * 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/acparser.h> #include <acpi/acdispat.h> #include <acpi/acnamesp.h> #define _COMPONENT ACPI_DISPATCHER ACPI_MODULE_NAME("dswstate") /* Local prototypes */ #ifdef ACPI_OBSOLETE_FUNCTIONS acpi_status acpi_ds_result_insert(void *object, u32 index, struct acpi_walk_state *walk_state); acpi_status acpi_ds_obj_stack_delete_all(struct acpi_walk_state *walk_state); acpi_status acpi_ds_obj_stack_pop_object(union acpi_operand_object **object, struct acpi_walk_state *walk_state); void *acpi_ds_obj_stack_get_value(u32 index, struct acpi_walk_state *walk_state); #endif #ifdef ACPI_FUTURE_USAGE /******************************************************************************* * * FUNCTION: acpi_ds_result_remove * * PARAMETERS: Object - Where to return the popped object * Index - Where to extract the object * walk_state - Current Walk state * * RETURN: Status * * DESCRIPTION: Pop an object off the bottom of this walk's result stack. In * other words, this is a FIFO. * ******************************************************************************/ acpi_status acpi_ds_result_remove(union acpi_operand_object **object, u32 index, struct acpi_walk_state *walk_state) { union acpi_generic_state *state; ACPI_FUNCTION_NAME("ds_result_remove"); state = walk_state->results; if (!state) { ACPI_ERROR((AE_INFO, "No result object pushed! State=%p", walk_state)); return (AE_NOT_EXIST); } if (index >= ACPI_OBJ_MAX_OPERAND) { ACPI_ERROR((AE_INFO, "Index out of range: %X State=%p Num=%X", index, walk_state, state->results.num_results)); } /* Check for a valid result object */ if (!state->results.obj_desc[index]) { ACPI_ERROR((AE_INFO, "Null operand! State=%p #Ops=%X, Index=%X", walk_state, state->results.num_results, index)); return (AE_AML_NO_RETURN_VALUE); } /* Remove the object */ state->results.num_results--; *object = state->results.obj_desc[index]; state->results.obj_desc[index] = NULL; ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] Index=%X State=%p Num=%X\n", *object, (*object) ? acpi_ut_get_object_type_name(*object) : "NULL", index, walk_state, state->results.num_results)); return (AE_OK); } #endif /* ACPI_FUTURE_USAGE */ /******************************************************************************* * * FUNCTION: acpi_ds_result_pop * * PARAMETERS: Object - Where to return the popped object * walk_state - Current Walk state * * RETURN: Status * * DESCRIPTION: Pop an object off the bottom of this walk's result stack. In * other words, this is a FIFO. * ******************************************************************************/ acpi_status acpi_ds_result_pop(union acpi_operand_object ** object, struct acpi_walk_state * walk_state) { acpi_native_uint index; union acpi_generic_state *state; ACPI_FUNCTION_NAME("ds_result_pop"); state = walk_state->results; if (!state) { return (AE_OK); } if (!state->results.num_results) { ACPI_ERROR((AE_INFO, "Result stack is empty! State=%p", walk_state)); return (AE_AML_NO_RETURN_VALUE); } /* Remove top element */ state->results.num_results--; for (index = ACPI_OBJ_NUM_OPERANDS; index; index--) { /* Check for a valid result object */ if (state->results.obj_desc[index - 1]) { *object = state->results.obj_desc[index - 1]; state->results.obj_desc[index - 1] = NULL; ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] Index=%X State=%p Num=%X\n", *object, (*object) ? acpi_ut_get_object_type_name(*object) : "NULL", (u32) index - 1, walk_state, state->results.num_results)); return (AE_OK); } } ACPI_ERROR((AE_INFO, "No result objects! State=%p", walk_state)); return (AE_AML_NO_RETURN_VALUE); } /******************************************************************************* * * FUNCTION: acpi_ds_result_pop_from_bottom * * PARAMETERS: Object - Where to return the popped object * walk_state - Current Walk state * * RETURN: Status * * DESCRIPTION: Pop an object off the bottom of this walk's result stack. In * other words, this is a FIFO. * ******************************************************************************/ acpi_status acpi_ds_result_pop_from_bottom(union acpi_operand_object ** object, struct acpi_walk_state * walk_state) { acpi_native_uint index; union acpi_generic_state *state; ACPI_FUNCTION_NAME("ds_result_pop_from_bottom"); state = walk_state->results; if (!state) { ACPI_ERROR((AE_INFO, "No result object pushed! State=%p", walk_state)); return (AE_NOT_EXIST); } if (!state->results.num_results) { ACPI_ERROR((AE_INFO, "No result objects! State=%p", walk_state)); return (AE_AML_NO_RETURN_VALUE); } /* Remove Bottom element */ *object = state->results.obj_desc[0]; /* Push entire stack down one element */ for (index = 0; index < state->results.num_results; index++) { state->results.obj_desc[index] = state->results.obj_desc[index + 1]; } state->results.num_results--; /* Check for a valid result object */ if (!*object) { ACPI_ERROR((AE_INFO, "Null operand! State=%p #Ops=%X Index=%X", walk_state, state->results.num_results, (u32) index)); return (AE_AML_NO_RETURN_VALUE); } ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] Results=%p State=%p\n", *object, (*object) ? acpi_ut_get_object_type_name(*object) : "NULL", state, walk_state)); return (AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ds_result_push * * PARAMETERS: Object - Where to return the popped object * walk_state - Current Walk state * * RETURN: Status * * DESCRIPTION: Push an object onto the current result stack * ******************************************************************************/ acpi_status acpi_ds_result_push(union acpi_operand_object * object, struct acpi_walk_state * walk_state) { union acpi_generic_state *state; ACPI_FUNCTION_NAME("ds_result_push"); state = walk_state->results; if (!state) { ACPI_ERROR((AE_INFO, "No result stack frame during push")); return (AE_AML_INTERNAL); } if (state->results.num_results == ACPI_OBJ_NUM_OPERANDS) { ACPI_ERROR((AE_INFO, "Result stack overflow: Obj=%p State=%p Num=%X", object, walk_state, state->results.num_results)); return (AE_STACK_OVERFLOW); } if (!object) { ACPI_ERROR((AE_INFO, "Null Object! Obj=%p State=%p Num=%X", object, walk_state, state->results.num_results)); return (AE_BAD_PARAMETER); } state->results.obj_desc[state->results.num_results] = object; state->results.num_results++; ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n", object, object ? acpi_ut_get_object_type_name((union acpi_operand_object *) object) : "NULL", walk_state, state->results.num_results, walk_state->current_result)); return (AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ds_result_stack_push * * PARAMETERS: walk_state - Current Walk state * * RETURN: Status * * DESCRIPTION: Push an object onto the walk_state result stack. * ******************************************************************************/ acpi_status acpi_ds_result_stack_push(struct acpi_walk_state * walk_state) { union acpi_generic_state *state; ACPI_FUNCTION_NAME("ds_result_stack_push"); state = acpi_ut_create_generic_state(); if (!state) { return (AE_NO_MEMORY); } state->common.data_type = ACPI_DESC_TYPE_STATE_RESULT; acpi_ut_push_generic_state(&walk_state->results, state); ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Results=%p State=%p\n", state, walk_state)); return (AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ds_result_stack_pop * * PARAMETERS: walk_state - Current Walk state * * RETURN: Status * * DESCRIPTION: Pop an object off of the walk_state result stack. * ******************************************************************************/ acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state * walk_state) { union acpi_generic_state *state; ACPI_FUNCTION_NAME("ds_result_stack_pop"); /* Check for stack underflow */ if (walk_state->results == NULL) { ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Underflow - State=%p\n", walk_state)); return (AE_AML_NO_OPERAND); } state = acpi_ut_pop_generic_state(&walk_state->results); ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Result=%p remaining_results=%X State=%p\n", state, state->results.num_results, walk_state)); acpi_ut_delete_generic_state(state); return (AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ds_obj_stack_push * * PARAMETERS: Object - Object to push * walk_state - Current Walk state * * RETURN: Status * * DESCRIPTION: Push an object onto this walk's object/operand stack * ******************************************************************************/ acpi_status acpi_ds_obj_stack_push(void *object, struct acpi_walk_state * walk_state) { ACPI_FUNCTION_NAME("ds_obj_stack_push"); /* Check for stack overflow */ if (walk_state->num_operands >= ACPI_OBJ_NUM_OPERANDS) { ACPI_ERROR((AE_INFO, "Object stack overflow! Obj=%p State=%p #Ops=%X", object, walk_state, walk_state->num_operands)); return (AE_STACK_OVERFLOW); } /* Put the object onto the stack */ walk_state->operands[walk_state->num_operands] = object; walk_state->num_operands++; ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n", object, acpi_ut_get_object_type_name((union acpi_operand_object *) object), walk_state, walk_state->num_operands)); return (AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ds_obj_stack_pop * * PARAMETERS: pop_count - Number of objects/entries to pop * walk_state - Current Walk state * * RETURN: Status * * DESCRIPTION: Pop this walk's object stack. Objects on the stack are NOT * deleted by this routine. * ******************************************************************************/ acpi_status acpi_ds_obj_stack_pop(u32 pop_count, struct acpi_walk_state * walk_state) { u32 i; ACPI_FUNCTION_NAME("ds_obj_stack_pop"); for (i = 0; i < pop_count; i++) { /* Check for stack underflow */ if (walk_state->num_operands == 0) { ACPI_ERROR((AE_INFO, "Object stack underflow! Count=%X State=%p #Ops=%X", pop_count, walk_state, walk_state->num_operands)); return (AE_STACK_UNDERFLOW); } /* Just set the stack entry to null */ walk_state->num_operands--; walk_state->operands[walk_state->num_operands] = NULL; } ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n", pop_count, walk_state, walk_state->num_operands)); return (AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ds_obj_stack_pop_and_delete * * PARAMETERS: pop_count - Number of objects/entries to pop * walk_state - Current Walk state * * RETURN: Status * * DESCRIPTION: Pop this walk's object stack and delete each object that is * popped off. * ******************************************************************************/ acpi_status acpi_ds_obj_stack_pop_and_delete(u32 pop_count, struct acpi_walk_state * walk_state) { u32 i; union acpi_operand_object *obj_desc; ACPI_FUNCTION_NAME("ds_obj_stack_pop_and_delete"); for (i = 0; i < pop_count; i++) { /* Check for stack underflow */ if (walk_state->num_operands == 0) { ACPI_ERROR((AE_INFO, "Object stack underflow! Count=%X State=%p #Ops=%X", pop_count, walk_state, walk_state->num_operands)); return (AE_STACK_UNDERFLOW); } /* Pop the stack and delete an object if present in this stack entry */ walk_state->num_operands--; obj_desc = walk_state->operands[walk_state->num_operands]; if (obj_desc) { acpi_ut_remove_reference(walk_state-> operands[walk_state-> num_operands]); walk_state->operands[walk_state->num_operands] = NULL; } } ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n", pop_count, walk_state, walk_state->num_operands)); return (AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ds_get_current_walk_state * * PARAMETERS: Thread - Get current active state for this Thread * * RETURN: Pointer to the current walk state * * DESCRIPTION: Get the walk state that is at the head of the list (the "current" * walk state.) * ******************************************************************************/ struct acpi_walk_state *acpi_ds_get_current_walk_state(struct acpi_thread_state *thread) { ACPI_FUNCTION_NAME("ds_get_current_walk_state"); if (!thread) { return (NULL); } ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Current walk_state %p\n", thread->walk_state_list)); return (thread->walk_state_list); } /******************************************************************************* * * FUNCTION: acpi_ds_push_walk_state * * PARAMETERS: walk_state - State to push * Thread - Thread state object * * RETURN: None * * DESCRIPTION: Place the Thread state at the head of the state list. * ******************************************************************************/ void acpi_ds_push_walk_state(struct acpi_walk_state *walk_state, struct acpi_thread_state *thread) { ACPI_FUNCTION_TRACE("ds_push_walk_state"); walk_state->next = thread->walk_state_list; thread->walk_state_list = walk_state; return_VOID; } /******************************************************************************* * * FUNCTION: acpi_ds_pop_walk_state * * PARAMETERS: Thread - Current thread state * * RETURN: A walk_state object popped from the thread's stack * * DESCRIPTION: Remove and return the walkstate object that is at the head of * the walk stack for the given walk list. NULL indicates that * the list is empty. * ******************************************************************************/ struct acpi_walk_state *acpi_ds_pop_walk_state(struct acpi_thread_state *thread) { struct acpi_walk_state *walk_state; ACPI_FUNCTION_TRACE("ds_pop_walk_state"); walk_state = thread->walk_state_list; if (walk_state) { /* Next walk state becomes the current walk state */ thread->walk_state_list = walk_state->next; /* * Don't clear the NEXT field, this serves as an indicator * that there is a parent WALK STATE * Do Not: walk_state->Next = NULL; */ } return_PTR(walk_state); } /******************************************************************************* * * FUNCTION: acpi_ds_create_walk_state * * PARAMETERS: owner_id - ID for object creation * Origin - Starting point for this walk * mth_desc - Method object * Thread - Current thread state * * RETURN: Pointer to the new walk state. * * DESCRIPTION: Allocate and initialize a new walk state. The current walk * state is set to this new state. * ******************************************************************************/ struct acpi_walk_state *acpi_ds_create_walk_state(acpi_owner_id owner_id, union acpi_parse_object *origin, union acpi_operand_object *mth_desc, struct acpi_thread_state *thread) { struct acpi_walk_state *walk_state; acpi_status status; ACPI_FUNCTION_TRACE("ds_create_walk_state"); walk_state = ACPI_MEM_CALLOCATE(sizeof(struct acpi_walk_state)); if (!walk_state) { return_PTR(NULL); } walk_state->data_type = ACPI_DESC_TYPE_WALK; walk_state->owner_id = owner_id; walk_state->origin = origin; walk_state->method_desc = mth_desc; walk_state->thread = thread; walk_state->parser_state.start_op = origin; /* Init the method args/local */ #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY)) acpi_ds_method_data_init(walk_state); #endif /* Create an initial result stack entry */ status = acpi_ds_result_stack_push(walk_state); if (ACPI_FAILURE(status)) { ACPI_MEM_FREE(walk_state); return_PTR(NULL); } /* Put the new state at the head of the walk list */ if (thread) { acpi_ds_push_walk_state(walk_state, thread); } return_PTR(walk_state); } /******************************************************************************* * * FUNCTION: acpi_ds_init_aml_walk * * PARAMETERS: walk_state - New state to be initialized * Op - Current parse op * method_node - Control method NS node, if any * aml_start - Start of AML * aml_length - Length of AML * Info - Method info block (params, etc.) * pass_number - 1, 2, or 3 * * RETURN: Status * * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk * ******************************************************************************/ acpi_status acpi_ds_init_aml_walk(struct acpi_walk_state *walk_state, union acpi_parse_object *op, struct acpi_namespace_node *method_node, u8 * aml_start, u32 aml_length, struct acpi_parameter_info *info, u8 pass_number) { acpi_status status; struct acpi_parse_state *parser_state = &walk_state->parser_state; union acpi_parse_object *extra_op; ACPI_FUNCTION_TRACE("ds_init_aml_walk"); walk_state->parser_state.aml = walk_state->parser_state.aml_start = aml_start; walk_state->parser_state.aml_end = walk_state->parser_state.pkg_end = aml_start + aml_length; /* The next_op of the next_walk will be the beginning of the method */ walk_state->next_op = NULL; walk_state->pass_number = pass_number; if (info) { if (info->parameter_type == ACPI_PARAM_GPE) { walk_state->gpe_event_info = ACPI_CAST_PTR(struct acpi_gpe_event_info, info->parameters); } else { walk_state->params = info->parameters; walk_state->caller_return_desc = &info->return_object; } } status = acpi_ps_init_scope(&walk_state->parser_state, op); if (ACPI_FAILURE(status)) { return_ACPI_STATUS(status); } if (method_node) { walk_state->parser_state.start_node = method_node; walk_state->walk_type = ACPI_WALK_METHOD; walk_state->method_node = method_node; walk_state->method_desc = acpi_ns_get_attached_object(method_node); /* Push start scope on scope stack and make it current */ status = acpi_ds_scope_stack_push(method_node, ACPI_TYPE_METHOD, walk_state); if (ACPI_FAILURE(status)) { return_ACPI_STATUS(status); } /* Init the method arguments */ status = acpi_ds_method_data_init_args(walk_state->params, ACPI_METHOD_NUM_ARGS, walk_state); if (ACPI_FAILURE(status)) { return_ACPI_STATUS(status); } } else { /* * Setup the current scope. * Find a Named Op that has a namespace node associated with it. * search upwards from this Op. Current scope is the first * Op with a namespace node. */ extra_op = parser_state->start_op; while (extra_op && !extra_op->common.node) { extra_op = extra_op->common.parent; } if (!extra_op) { parser_state->start_node = NULL; } else { parser_state->start_node = extra_op->common.node; } if (parser_state->start_node) { /* Push start scope on scope stack and make it current */ status = acpi_ds_scope_stack_push(parser_state->start_node, parser_state->start_node-> type, walk_state); if (ACPI_FAILURE(status)) { return_ACPI_STATUS(status); } } } status = acpi_ds_init_callbacks(walk_state, pass_number); return_ACPI_STATUS(status); } /******************************************************************************* * * FUNCTION: acpi_ds_delete_walk_state * * PARAMETERS: walk_state - State to delete * * RETURN: Status * * DESCRIPTION: Delete a walk state including all internal data structures * ******************************************************************************/ void acpi_ds_delete_walk_state(struct acpi_walk_state *walk_state) { union acpi_generic_state *state; ACPI_FUNCTION_TRACE_PTR("ds_delete_walk_state", walk_state); if (!walk_state) { return; } if (walk_state->data_type != ACPI_DESC_TYPE_WALK) { ACPI_ERROR((AE_INFO, "%p is not a valid walk state", walk_state)); return; } if (walk_state->parser_state.scope) { ACPI_ERROR((AE_INFO, "%p walk still has a scope list", walk_state)); } /* Always must free any linked control states */ while (walk_state->control_state) { state = walk_state->control_state; walk_state->control_state = state->common.next; acpi_ut_delete_generic_state(state); } /* Always must free any linked parse states */ while (walk_state->scope_info) { state = walk_state->scope_info; walk_state->scope_info = state->common.next; acpi_ut_delete_generic_state(state); } /* Always must free any stacked result states */ while (walk_state->results) { state = walk_state->results; walk_state->results = state->common.next; acpi_ut_delete_generic_state(state); } ACPI_MEM_FREE(walk_state); return_VOID; } #ifdef ACPI_OBSOLETE_FUNCTIONS /******************************************************************************* * * FUNCTION: acpi_ds_result_insert * * PARAMETERS: Object - Object to push * Index - Where to insert the object * walk_state - Current Walk state * * RETURN: Status * * DESCRIPTION: Insert an object onto this walk's result stack * ******************************************************************************/ acpi_status acpi_ds_result_insert(void *object, u32 index, struct acpi_walk_state *walk_state) { union acpi_generic_state *state; ACPI_FUNCTION_NAME("ds_result_insert"); state = walk_state->results; if (!state) { ACPI_ERROR((AE_INFO, "No result object pushed! State=%p", walk_state)); return (AE_NOT_EXIST); } if (index >= ACPI_OBJ_NUM_OPERANDS) { ACPI_ERROR((AE_INFO, "Index out of range: %X Obj=%p State=%p Num=%X", index, object, walk_state, state->results.num_results)); return (AE_BAD_PARAMETER); } if (!object) { ACPI_ERROR((AE_INFO, "Null Object! Index=%X Obj=%p State=%p Num=%X", index, object, walk_state, state->results.num_results)); return (AE_BAD_PARAMETER); } state->results.obj_desc[index] = object; state->results.num_results++; ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n", object, object ? acpi_ut_get_object_type_name((union acpi_operand_object *) object) : "NULL", walk_state, state->results.num_results, walk_state->current_result)); return (AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ds_obj_stack_delete_all * * PARAMETERS: walk_state - Current Walk state * * RETURN: Status * * DESCRIPTION: Clear the object stack by deleting all objects that are on it. * Should be used with great care, if at all! * ******************************************************************************/ acpi_status acpi_ds_obj_stack_delete_all(struct acpi_walk_state * walk_state) { u32 i; ACPI_FUNCTION_TRACE_PTR("ds_obj_stack_delete_all", walk_state); /* The stack size is configurable, but fixed */ for (i = 0; i < ACPI_OBJ_NUM_OPERANDS; i++) { if (walk_state->operands[i]) { acpi_ut_remove_reference(walk_state->operands[i]); walk_state->operands[i] = NULL; } } return_ACPI_STATUS(AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ds_obj_stack_pop_object * * PARAMETERS: Object - Where to return the popped object * walk_state - Current Walk state * * RETURN: Status * * DESCRIPTION: Pop this walk's object stack. Objects on the stack are NOT * deleted by this routine. * ******************************************************************************/ acpi_status acpi_ds_obj_stack_pop_object(union acpi_operand_object **object, struct acpi_walk_state *walk_state) { ACPI_FUNCTION_NAME("ds_obj_stack_pop_object"); /* Check for stack underflow */ if (walk_state->num_operands == 0) { ACPI_ERROR((AE_INFO, "Missing operand/stack empty! State=%p #Ops=%X", walk_state, walk_state->num_operands)); *object = NULL; return (AE_AML_NO_OPERAND); } /* Pop the stack */ walk_state->num_operands--; /* Check for a valid operand */ if (!walk_state->operands[walk_state->num_operands]) { ACPI_ERROR((AE_INFO, "Null operand! State=%p #Ops=%X", walk_state, walk_state->num_operands)); *object = NULL; return (AE_AML_NO_OPERAND); } /* Get operand and set stack entry to null */ *object = walk_state->operands[walk_state->num_operands]; walk_state->operands[walk_state->num_operands] = NULL; ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n", *object, acpi_ut_get_object_type_name(*object), walk_state, walk_state->num_operands)); return (AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ds_obj_stack_get_value * * PARAMETERS: Index - Stack index whose value is desired. Based * on the top of the stack (index=0 == top) * walk_state - Current Walk state * * RETURN: Pointer to the requested operand * * DESCRIPTION: Retrieve an object from this walk's operand stack. Index must * be within the range of the current stack pointer. * ******************************************************************************/ void *acpi_ds_obj_stack_get_value(u32 index, struct acpi_walk_state *walk_state) { ACPI_FUNCTION_TRACE_PTR("ds_obj_stack_get_value", walk_state); /* Can't do it if the stack is empty */ if (walk_state->num_operands == 0) { return_PTR(NULL); } /* or if the index is past the top of the stack */ if (index > (walk_state->num_operands - (u32) 1)) { return_PTR(NULL); } return_PTR(walk_state-> operands[(acpi_native_uint) (walk_state->num_operands - 1) - index]); } #endif