1 /******************************************************************************
2  *
3  * Module Name: psscope - Parser scope stack management routines
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2011, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acparser.h"
47 
48 #define _COMPONENT          ACPI_PARSER
49 ACPI_MODULE_NAME("psscope")
50 
51 /*******************************************************************************
52  *
53  * FUNCTION:    acpi_ps_get_parent_scope
54  *
55  * PARAMETERS:  parser_state        - Current parser state object
56  *
57  * RETURN:      Pointer to an Op object
58  *
59  * DESCRIPTION: Get parent of current op being parsed
60  *
61  ******************************************************************************/
acpi_ps_get_parent_scope(struct acpi_parse_state * parser_state)62 union acpi_parse_object *acpi_ps_get_parent_scope(struct acpi_parse_state
63 						  *parser_state)
64 {
65 
66 	return (parser_state->scope->parse_scope.op);
67 }
68 
69 /*******************************************************************************
70  *
71  * FUNCTION:    acpi_ps_has_completed_scope
72  *
73  * PARAMETERS:  parser_state        - Current parser state object
74  *
75  * RETURN:      Boolean, TRUE = scope completed.
76  *
77  * DESCRIPTION: Is parsing of current argument complete?  Determined by
78  *              1) AML pointer is at or beyond the end of the scope
79  *              2) The scope argument count has reached zero.
80  *
81  ******************************************************************************/
82 
acpi_ps_has_completed_scope(struct acpi_parse_state * parser_state)83 u8 acpi_ps_has_completed_scope(struct acpi_parse_state * parser_state)
84 {
85 
86 	return ((u8)
87 		((parser_state->aml >= parser_state->scope->parse_scope.arg_end
88 		  || !parser_state->scope->parse_scope.arg_count)));
89 }
90 
91 /*******************************************************************************
92  *
93  * FUNCTION:    acpi_ps_init_scope
94  *
95  * PARAMETERS:  parser_state        - Current parser state object
96  *              Root                - the Root Node of this new scope
97  *
98  * RETURN:      Status
99  *
100  * DESCRIPTION: Allocate and init a new scope object
101  *
102  ******************************************************************************/
103 
104 acpi_status
acpi_ps_init_scope(struct acpi_parse_state * parser_state,union acpi_parse_object * root_op)105 acpi_ps_init_scope(struct acpi_parse_state * parser_state,
106 		   union acpi_parse_object * root_op)
107 {
108 	union acpi_generic_state *scope;
109 
110 	ACPI_FUNCTION_TRACE_PTR(ps_init_scope, root_op);
111 
112 	scope = acpi_ut_create_generic_state();
113 	if (!scope) {
114 		return_ACPI_STATUS(AE_NO_MEMORY);
115 	}
116 
117 	scope->common.descriptor_type = ACPI_DESC_TYPE_STATE_RPSCOPE;
118 	scope->parse_scope.op = root_op;
119 	scope->parse_scope.arg_count = ACPI_VAR_ARGS;
120 	scope->parse_scope.arg_end = parser_state->aml_end;
121 	scope->parse_scope.pkg_end = parser_state->aml_end;
122 
123 	parser_state->scope = scope;
124 	parser_state->start_op = root_op;
125 
126 	return_ACPI_STATUS(AE_OK);
127 }
128 
129 /*******************************************************************************
130  *
131  * FUNCTION:    acpi_ps_push_scope
132  *
133  * PARAMETERS:  parser_state        - Current parser state object
134  *              Op                  - Current op to be pushed
135  *              remaining_args      - List of args remaining
136  *              arg_count           - Fixed or variable number of args
137  *
138  * RETURN:      Status
139  *
140  * DESCRIPTION: Push current op to begin parsing its argument
141  *
142  ******************************************************************************/
143 
144 acpi_status
acpi_ps_push_scope(struct acpi_parse_state * parser_state,union acpi_parse_object * op,u32 remaining_args,u32 arg_count)145 acpi_ps_push_scope(struct acpi_parse_state *parser_state,
146 		   union acpi_parse_object *op,
147 		   u32 remaining_args, u32 arg_count)
148 {
149 	union acpi_generic_state *scope;
150 
151 	ACPI_FUNCTION_TRACE_PTR(ps_push_scope, op);
152 
153 	scope = acpi_ut_create_generic_state();
154 	if (!scope) {
155 		return_ACPI_STATUS(AE_NO_MEMORY);
156 	}
157 
158 	scope->common.descriptor_type = ACPI_DESC_TYPE_STATE_PSCOPE;
159 	scope->parse_scope.op = op;
160 	scope->parse_scope.arg_list = remaining_args;
161 	scope->parse_scope.arg_count = arg_count;
162 	scope->parse_scope.pkg_end = parser_state->pkg_end;
163 
164 	/* Push onto scope stack */
165 
166 	acpi_ut_push_generic_state(&parser_state->scope, scope);
167 
168 	if (arg_count == ACPI_VAR_ARGS) {
169 
170 		/* Multiple arguments */
171 
172 		scope->parse_scope.arg_end = parser_state->pkg_end;
173 	} else {
174 		/* Single argument */
175 
176 		scope->parse_scope.arg_end = ACPI_TO_POINTER(ACPI_MAX_PTR);
177 	}
178 
179 	return_ACPI_STATUS(AE_OK);
180 }
181 
182 /*******************************************************************************
183  *
184  * FUNCTION:    acpi_ps_pop_scope
185  *
186  * PARAMETERS:  parser_state        - Current parser state object
187  *              Op                  - Where the popped op is returned
188  *              arg_list            - Where the popped "next argument" is
189  *                                    returned
190  *              arg_count           - Count of objects in arg_list
191  *
192  * RETURN:      Status
193  *
194  * DESCRIPTION: Return to parsing a previous op
195  *
196  ******************************************************************************/
197 
198 void
acpi_ps_pop_scope(struct acpi_parse_state * parser_state,union acpi_parse_object ** op,u32 * arg_list,u32 * arg_count)199 acpi_ps_pop_scope(struct acpi_parse_state *parser_state,
200 		  union acpi_parse_object **op, u32 * arg_list, u32 * arg_count)
201 {
202 	union acpi_generic_state *scope = parser_state->scope;
203 
204 	ACPI_FUNCTION_TRACE(ps_pop_scope);
205 
206 	/* Only pop the scope if there is in fact a next scope */
207 
208 	if (scope->common.next) {
209 		scope = acpi_ut_pop_generic_state(&parser_state->scope);
210 
211 		/* Return to parsing previous op */
212 
213 		*op = scope->parse_scope.op;
214 		*arg_list = scope->parse_scope.arg_list;
215 		*arg_count = scope->parse_scope.arg_count;
216 		parser_state->pkg_end = scope->parse_scope.pkg_end;
217 
218 		/* All done with this scope state structure */
219 
220 		acpi_ut_delete_generic_state(scope);
221 	} else {
222 		/* Empty parse stack, prepare to fetch next opcode */
223 
224 		*op = NULL;
225 		*arg_list = 0;
226 		*arg_count = 0;
227 	}
228 
229 	ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
230 			  "Popped Op %p Args %X\n", *op, *arg_count));
231 	return_VOID;
232 }
233 
234 /*******************************************************************************
235  *
236  * FUNCTION:    acpi_ps_cleanup_scope
237  *
238  * PARAMETERS:  parser_state        - Current parser state object
239  *
240  * RETURN:      None
241  *
242  * DESCRIPTION: Destroy available list, remaining stack levels, and return
243  *              root scope
244  *
245  ******************************************************************************/
246 
acpi_ps_cleanup_scope(struct acpi_parse_state * parser_state)247 void acpi_ps_cleanup_scope(struct acpi_parse_state *parser_state)
248 {
249 	union acpi_generic_state *scope;
250 
251 	ACPI_FUNCTION_TRACE_PTR(ps_cleanup_scope, parser_state);
252 
253 	if (!parser_state) {
254 		return_VOID;
255 	}
256 
257 	/* Delete anything on the scope stack */
258 
259 	while (parser_state->scope) {
260 		scope = acpi_ut_pop_generic_state(&parser_state->scope);
261 		acpi_ut_delete_generic_state(scope);
262 	}
263 
264 	return_VOID;
265 }
266