1 | // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 |
2 | /****************************************************************************** |
3 | * |
4 | * Module Name: exstorob - AML object store support, store to object |
5 | * |
6 | * Copyright (C) 2000 - 2023, Intel Corp. |
7 | * |
8 | *****************************************************************************/ |
9 | |
10 | #include <acpi/acpi.h> |
11 | #include "accommon.h" |
12 | #include "acinterp.h" |
13 | |
14 | #define _COMPONENT ACPI_EXECUTER |
15 | ACPI_MODULE_NAME("exstorob" ) |
16 | |
17 | /******************************************************************************* |
18 | * |
19 | * FUNCTION: acpi_ex_store_buffer_to_buffer |
20 | * |
21 | * PARAMETERS: source_desc - Source object to copy |
22 | * target_desc - Destination object of the copy |
23 | * |
24 | * RETURN: Status |
25 | * |
26 | * DESCRIPTION: Copy a buffer object to another buffer object. |
27 | * |
28 | ******************************************************************************/ |
29 | acpi_status |
30 | acpi_ex_store_buffer_to_buffer(union acpi_operand_object *source_desc, |
31 | union acpi_operand_object *target_desc) |
32 | { |
33 | u32 length; |
34 | u8 *buffer; |
35 | |
36 | ACPI_FUNCTION_TRACE_PTR(ex_store_buffer_to_buffer, source_desc); |
37 | |
38 | /* If Source and Target are the same, just return */ |
39 | |
40 | if (source_desc == target_desc) { |
41 | return_ACPI_STATUS(AE_OK); |
42 | } |
43 | |
44 | /* We know that source_desc is a buffer by now */ |
45 | |
46 | buffer = ACPI_CAST_PTR(u8, source_desc->buffer.pointer); |
47 | length = source_desc->buffer.length; |
48 | |
49 | /* |
50 | * If target is a buffer of length zero or is a static buffer, |
51 | * allocate a new buffer of the proper length |
52 | */ |
53 | if ((target_desc->buffer.length == 0) || |
54 | (target_desc->common.flags & AOPOBJ_STATIC_POINTER)) { |
55 | target_desc->buffer.pointer = ACPI_ALLOCATE(length); |
56 | if (!target_desc->buffer.pointer) { |
57 | return_ACPI_STATUS(AE_NO_MEMORY); |
58 | } |
59 | |
60 | target_desc->buffer.length = length; |
61 | } |
62 | |
63 | /* Copy source buffer to target buffer */ |
64 | |
65 | if (length <= target_desc->buffer.length) { |
66 | |
67 | /* Clear existing buffer and copy in the new one */ |
68 | |
69 | memset(target_desc->buffer.pointer, 0, |
70 | target_desc->buffer.length); |
71 | memcpy(target_desc->buffer.pointer, buffer, length); |
72 | |
73 | #ifdef ACPI_OBSOLETE_BEHAVIOR |
74 | /* |
75 | * NOTE: ACPI versions up to 3.0 specified that the buffer must be |
76 | * truncated if the string is smaller than the buffer. However, "other" |
77 | * implementations of ACPI never did this and thus became the defacto |
78 | * standard. ACPI 3.0A changes this behavior such that the buffer |
79 | * is no longer truncated. |
80 | */ |
81 | |
82 | /* |
83 | * OBSOLETE BEHAVIOR: |
84 | * If the original source was a string, we must truncate the buffer, |
85 | * according to the ACPI spec. Integer-to-Buffer and Buffer-to-Buffer |
86 | * copy must not truncate the original buffer. |
87 | */ |
88 | if (original_src_type == ACPI_TYPE_STRING) { |
89 | |
90 | /* Set the new length of the target */ |
91 | |
92 | target_desc->buffer.length = length; |
93 | } |
94 | #endif |
95 | } else { |
96 | /* Truncate the source, copy only what will fit */ |
97 | |
98 | memcpy(target_desc->buffer.pointer, buffer, |
99 | target_desc->buffer.length); |
100 | |
101 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, |
102 | "Truncating source buffer from %X to %X\n" , |
103 | length, target_desc->buffer.length)); |
104 | } |
105 | |
106 | /* Copy flags */ |
107 | |
108 | target_desc->buffer.flags = source_desc->buffer.flags; |
109 | target_desc->common.flags &= ~AOPOBJ_STATIC_POINTER; |
110 | return_ACPI_STATUS(AE_OK); |
111 | } |
112 | |
113 | /******************************************************************************* |
114 | * |
115 | * FUNCTION: acpi_ex_store_string_to_string |
116 | * |
117 | * PARAMETERS: source_desc - Source object to copy |
118 | * target_desc - Destination object of the copy |
119 | * |
120 | * RETURN: Status |
121 | * |
122 | * DESCRIPTION: Copy a String object to another String object |
123 | * |
124 | ******************************************************************************/ |
125 | |
126 | acpi_status |
127 | acpi_ex_store_string_to_string(union acpi_operand_object *source_desc, |
128 | union acpi_operand_object *target_desc) |
129 | { |
130 | u32 length; |
131 | u8 *buffer; |
132 | |
133 | ACPI_FUNCTION_TRACE_PTR(ex_store_string_to_string, source_desc); |
134 | |
135 | /* If Source and Target are the same, just return */ |
136 | |
137 | if (source_desc == target_desc) { |
138 | return_ACPI_STATUS(AE_OK); |
139 | } |
140 | |
141 | /* We know that source_desc is a string by now */ |
142 | |
143 | buffer = ACPI_CAST_PTR(u8, source_desc->string.pointer); |
144 | length = source_desc->string.length; |
145 | |
146 | /* |
147 | * Replace existing string value if it will fit and the string |
148 | * pointer is not a static pointer (part of an ACPI table) |
149 | */ |
150 | if ((length < target_desc->string.length) && |
151 | (!(target_desc->common.flags & AOPOBJ_STATIC_POINTER))) { |
152 | /* |
153 | * String will fit in existing non-static buffer. |
154 | * Clear old string and copy in the new one |
155 | */ |
156 | memset(target_desc->string.pointer, 0, |
157 | (acpi_size)target_desc->string.length + 1); |
158 | memcpy(target_desc->string.pointer, buffer, length); |
159 | } else { |
160 | /* |
161 | * Free the current buffer, then allocate a new buffer |
162 | * large enough to hold the value |
163 | */ |
164 | if (target_desc->string.pointer && |
165 | (!(target_desc->common.flags & AOPOBJ_STATIC_POINTER))) { |
166 | |
167 | /* Only free if not a pointer into the DSDT */ |
168 | |
169 | ACPI_FREE(target_desc->string.pointer); |
170 | } |
171 | |
172 | target_desc->string.pointer = |
173 | ACPI_ALLOCATE_ZEROED((acpi_size)length + 1); |
174 | |
175 | if (!target_desc->string.pointer) { |
176 | return_ACPI_STATUS(AE_NO_MEMORY); |
177 | } |
178 | |
179 | target_desc->common.flags &= ~AOPOBJ_STATIC_POINTER; |
180 | memcpy(target_desc->string.pointer, buffer, length); |
181 | } |
182 | |
183 | /* Set the new target length */ |
184 | |
185 | target_desc->string.length = length; |
186 | return_ACPI_STATUS(AE_OK); |
187 | } |
188 | |