BaseTools: Add DevicePath support for PCD values
[mirror_edk2.git] / BaseTools / Source / C / DevicePath / UefiDevicePathLib.c
1 /** @file
2 Device Path services. The thing to remember is device paths are built out of
3 nodes. The device path is terminated by an end node that is length
4 sizeof(EFI_DEVICE_PATH_PROTOCOL). That would be why there is sizeof(EFI_DEVICE_PATH_PROTOCOL)
5 all over this file.
6
7 The only place where multi-instance device paths are supported is in
8 environment varibles. Multi-instance device paths should never be placed
9 on a Handle.
10
11 Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
12 This program and the accompanying materials
13 are licensed and made available under the terms and conditions of the BSD License
14 which accompanies this distribution. The full text of the license may be found at
15 http://opensource.org/licenses/bsd-license.php.
16
17 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
18 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
19
20 **/
21
22
23 #include "UefiDevicePathLib.h"
24
25 /**
26 Returns the size of a device path in bytes.
27
28 This function returns the size, in bytes, of the device path data structure
29 specified by DevicePath including the end of device path node.
30 If DevicePath is NULL or invalid, then 0 is returned.
31
32 @param DevicePath A pointer to a device path data structure.
33
34 @retval 0 If DevicePath is NULL or invalid.
35 @retval Others The size of a device path in bytes.
36
37 **/
38 UINTN
39 GetDevicePathSize (
40 CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath
41 )
42 {
43 return UefiDevicePathLibGetDevicePathSize (DevicePath);
44 }
45
46 /**
47 Creates a new copy of an existing device path.
48
49 This function allocates space for a new copy of the device path specified by DevicePath.
50 If DevicePath is NULL, then NULL is returned. If the memory is successfully
51 allocated, then the contents of DevicePath are copied to the newly allocated
52 buffer, and a pointer to that buffer is returned. Otherwise, NULL is returned.
53 The memory for the new device path is allocated from EFI boot services memory.
54 It is the responsibility of the caller to free the memory allocated.
55
56 @param DevicePath A pointer to a device path data structure.
57
58 @retval NULL DevicePath is NULL or invalid.
59 @retval Others A pointer to the duplicated device path.
60
61 **/
62 EFI_DEVICE_PATH_PROTOCOL *
63 DuplicateDevicePath (
64 CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath
65 )
66 {
67 return UefiDevicePathLibDuplicateDevicePath (DevicePath);
68 }
69
70 /**
71 Creates a new device path by appending a second device path to a first device path.
72
73 This function creates a new device path by appending a copy of SecondDevicePath
74 to a copy of FirstDevicePath in a newly allocated buffer. Only the end-of-device-path
75 device node from SecondDevicePath is retained. The newly created device path is
76 returned. If FirstDevicePath is NULL, then it is ignored, and a duplicate of
77 SecondDevicePath is returned. If SecondDevicePath is NULL, then it is ignored,
78 and a duplicate of FirstDevicePath is returned. If both FirstDevicePath and
79 SecondDevicePath are NULL, then a copy of an end-of-device-path is returned.
80
81 If there is not enough memory for the newly allocated buffer, then NULL is returned.
82 The memory for the new device path is allocated from EFI boot services memory.
83 It is the responsibility of the caller to free the memory allocated.
84
85 @param FirstDevicePath A pointer to a device path data structure.
86 @param SecondDevicePath A pointer to a device path data structure.
87
88 @retval NULL If there is not enough memory for the newly allocated buffer.
89 @retval NULL If FirstDevicePath or SecondDevicePath is invalid.
90 @retval Others A pointer to the new device path if success.
91 Or a copy an end-of-device-path if both FirstDevicePath and SecondDevicePath are NULL.
92
93 **/
94 EFI_DEVICE_PATH_PROTOCOL *
95 AppendDevicePath (
96 CONST EFI_DEVICE_PATH_PROTOCOL *FirstDevicePath, OPTIONAL
97 CONST EFI_DEVICE_PATH_PROTOCOL *SecondDevicePath OPTIONAL
98 )
99 {
100 return UefiDevicePathLibAppendDevicePath (FirstDevicePath, SecondDevicePath);
101 }
102
103 /**
104 Creates a new path by appending the device node to the device path.
105
106 This function creates a new device path by appending a copy of the device node
107 specified by DevicePathNode to a copy of the device path specified by DevicePath
108 in an allocated buffer. The end-of-device-path device node is moved after the
109 end of the appended device node.
110 If DevicePathNode is NULL then a copy of DevicePath is returned.
111 If DevicePath is NULL then a copy of DevicePathNode, followed by an end-of-device
112 path device node is returned.
113 If both DevicePathNode and DevicePath are NULL then a copy of an end-of-device-path
114 device node is returned.
115 If there is not enough memory to allocate space for the new device path, then
116 NULL is returned.
117 The memory is allocated from EFI boot services memory. It is the responsibility
118 of the caller to free the memory allocated.
119
120 @param DevicePath A pointer to a device path data structure.
121 @param DevicePathNode A pointer to a single device path node.
122
123 @retval NULL If there is not enough memory for the new device path.
124 @retval Others A pointer to the new device path if success.
125 A copy of DevicePathNode followed by an end-of-device-path node
126 if both FirstDevicePath and SecondDevicePath are NULL.
127 A copy of an end-of-device-path node if both FirstDevicePath
128 and SecondDevicePath are NULL.
129
130 **/
131 EFI_DEVICE_PATH_PROTOCOL *
132 AppendDevicePathNode (
133 CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath, OPTIONAL
134 CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathNode OPTIONAL
135 )
136 {
137 return UefiDevicePathLibAppendDevicePathNode (DevicePath, DevicePathNode);
138 }
139
140 /**
141 Creates a new device path by appending the specified device path instance to the specified device
142 path.
143
144 This function creates a new device path by appending a copy of the device path
145 instance specified by DevicePathInstance to a copy of the device path specified
146 by DevicePath in a allocated buffer.
147 The end-of-device-path device node is moved after the end of the appended device
148 path instance and a new end-of-device-path-instance node is inserted between.
149 If DevicePath is NULL, then a copy if DevicePathInstance is returned.
150 If DevicePathInstance is NULL, then NULL is returned.
151 If DevicePath or DevicePathInstance is invalid, then NULL is returned.
152 If there is not enough memory to allocate space for the new device path, then
153 NULL is returned.
154 The memory is allocated from EFI boot services memory. It is the responsibility
155 of the caller to free the memory allocated.
156
157 @param DevicePath A pointer to a device path data structure.
158 @param DevicePathInstance A pointer to a device path instance.
159
160 @return A pointer to the new device path.
161
162 **/
163 EFI_DEVICE_PATH_PROTOCOL *
164 AppendDevicePathInstance (
165 CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath, OPTIONAL
166 CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathInstance OPTIONAL
167 )
168 {
169 return UefiDevicePathLibAppendDevicePathInstance (DevicePath, DevicePathInstance);
170 }
171
172 /**
173 Creates a copy of the current device path instance and returns a pointer to the next device path
174 instance.
175
176 This function creates a copy of the current device path instance. It also updates
177 DevicePath to point to the next device path instance in the device path (or NULL
178 if no more) and updates Size to hold the size of the device path instance copy.
179 If DevicePath is NULL, then NULL is returned.
180 If DevicePath points to a invalid device path, then NULL is returned.
181 If there is not enough memory to allocate space for the new device path, then
182 NULL is returned.
183 The memory is allocated from EFI boot services memory. It is the responsibility
184 of the caller to free the memory allocated.
185 If Size is NULL, then ASSERT().
186
187 @param DevicePath On input, this holds the pointer to the current
188 device path instance. On output, this holds
189 the pointer to the next device path instance
190 or NULL if there are no more device path
191 instances in the device path pointer to a
192 device path data structure.
193 @param Size On output, this holds the size of the device
194 path instance, in bytes or zero, if DevicePath
195 is NULL.
196
197 @return A pointer to the current device path instance.
198
199 **/
200 EFI_DEVICE_PATH_PROTOCOL *
201 GetNextDevicePathInstance (
202 EFI_DEVICE_PATH_PROTOCOL **DevicePath,
203 UINTN *Size
204 )
205 {
206 return UefiDevicePathLibGetNextDevicePathInstance (DevicePath, Size);
207 }
208
209 /**
210 Creates a device node.
211
212 This function creates a new device node in a newly allocated buffer of size
213 NodeLength and initializes the device path node header with NodeType and NodeSubType.
214 The new device path node is returned.
215 If NodeLength is smaller than a device path header, then NULL is returned.
216 If there is not enough memory to allocate space for the new device path, then
217 NULL is returned.
218 The memory is allocated from EFI boot services memory. It is the responsibility
219 of the caller to free the memory allocated.
220
221 @param NodeType The device node type for the new device node.
222 @param NodeSubType The device node sub-type for the new device node.
223 @param NodeLength The length of the new device node.
224
225 @return The new device path.
226
227 **/
228 EFI_DEVICE_PATH_PROTOCOL *
229 CreateDeviceNode (
230 UINT8 NodeType,
231 UINT8 NodeSubType,
232 UINT16 NodeLength
233 )
234 {
235 return UefiDevicePathLibCreateDeviceNode (NodeType, NodeSubType, NodeLength);
236 }
237
238 /**
239 Determines if a device path is single or multi-instance.
240
241 This function returns TRUE if the device path specified by DevicePath is
242 multi-instance.
243 Otherwise, FALSE is returned.
244 If DevicePath is NULL or invalid, then FALSE is returned.
245
246 @param DevicePath A pointer to a device path data structure.
247
248 @retval TRUE DevicePath is multi-instance.
249 @retval FALSE DevicePath is not multi-instance, or DevicePath
250 is NULL or invalid.
251
252 **/
253 BOOLEAN
254 IsDevicePathMultiInstance (
255 CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath
256 )
257 {
258 return UefiDevicePathLibIsDevicePathMultiInstance (DevicePath);
259 }
260
261 /**
262 Convert text to the binary representation of a device node.
263
264 @param TextDeviceNode TextDeviceNode points to the text representation of a device
265 node. Conversion starts with the first character and continues
266 until the first non-device node character.
267
268 @return A pointer to the EFI device node or NULL if TextDeviceNode is NULL or there was
269 insufficient memory or text unsupported.
270
271 **/
272 EFI_DEVICE_PATH_PROTOCOL *
273 ConvertTextToDeviceNode (
274 CONST CHAR16 *TextDeviceNode
275 )
276 {
277 return UefiDevicePathLibConvertTextToDeviceNode (TextDeviceNode);
278 }
279
280 /**
281 Convert text to the binary representation of a device path.
282
283
284 @param TextDevicePath TextDevicePath points to the text representation of a device
285 path. Conversion starts with the first character and continues
286 until the first non-device node character.
287
288 @return A pointer to the allocated device path or NULL if TextDeviceNode is NULL or
289 there was insufficient memory.
290
291 **/
292 EFI_DEVICE_PATH_PROTOCOL *
293 ConvertTextToDevicePath (
294 CONST CHAR16 *TextDevicePath
295 )
296 {
297 return UefiDevicePathLibConvertTextToDevicePath (TextDevicePath);
298 }