1 /*++
2 
3 Copyright (c) 2004 - 2006, Intel Corporation. All rights reserved.<BR>
4 This program and the accompanying materials
5 are licensed and made available under the terms and conditions of the BSD License
6 which accompanies this distribution.  The full text of the license may be found at
7 http://opensource.org/licenses/bsd-license.php
8 
9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
11 
12 
13 Module Name:
14 
15   EdkIIGlueDevicePathLib.h
16 
17 Abstract:
18 
19   Public header file for Device Path Lib
20 
21 --*/
22 
23 #ifndef __EDKII_GLUE_DEVICE_PATH_LIB_H__
24 #define __EDKII_GLUE_DEVICE_PATH_LIB_H__
25 
26 
27 #define GetDevicePathSize(_DEVICEPATH)                      GlueGetDevicePathSize(_DEVICEPATH)
28 #define DuplicateDevicePath(_DEVICEPATH)                    GlueDuplicateDevicePath(_DEVICEPATH)
29 #define AppendDevicePath(_FIRSTPATH, _SECONDPATH)           GlueAppendDevicePath(_FIRSTPATH, _SECONDPATH)
30 #define AppendDevicePathNode(_DEVICEPATH, _DEVICEPATHNODE)  GlueAppendDevicePathNode(_DEVICEPATH, _DEVICEPATHNODE)
31 #define AppendDevicePathInstance(_SOURCE, _INSTANCE)        GlueAppendDevicePathInstance(_SOURCE,_INSTANCE)
32 #define GetNextDevicePathInstance(_DEVICEPATH, _SIZE)       GlueGetNextDevicePathInstance(_DEVICEPATH, _SIZE)
33 #define IsDevicePathMultiInstance(_DEVICEPATH)              GlueIsDevicePathMultiInstance(_DEVICEPATH)
34 #define DevicePathFromHandle(_HANDLE)                       GlueDevicePathFromHandle(_HANDLE)
35 #define FileDevicePath(_DEVICE, _FILENAME)                  GlueFileDevicePath(_DEVICE, _FILENAME)
36 
37 
38 /**
39   Returns the size of a device path in bytes.
40 
41   This function returns the size, in bytes, of the device path data structure specified by
42   DevicePath including the end of device path node.  If DevicePath is NULL, then 0 is returned.
43 
44   @param  DevicePath                 A pointer to a device path data structure.
45 
46   @return The size of a device path in bytes.
47 
48 **/
49 UINTN
50 EFIAPI
51 GlueGetDevicePathSize (
52   IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath
53   );
54 
55 /**
56   Creates a new device path by appending a second device path to a first device path.
57 
58   This function allocates space for a new copy of the device path specified by DevicePath.  If
59   DevicePath is NULL, then NULL is returned.  If the memory is successfully allocated, then the
60   contents of DevicePath are copied to the newly allocated buffer, and a pointer to that buffer
61   is returned.  Otherwise, NULL is returned.
62 
63   @param  DevicePath                 A pointer to a device path data structure.
64 
65   @return A pointer to the duplicated device path.
66 
67 **/
68 EFI_DEVICE_PATH_PROTOCOL *
69 EFIAPI
70 GlueDuplicateDevicePath (
71   IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath
72   );
73 
74 /**
75   Creates a new device path by appending a second device path to a first device path.
76 
77   This function creates a new device path by appending a copy of SecondDevicePath to a copy of
78   FirstDevicePath in a newly allocated buffer.  Only the end-of-device-path device node from
79   SecondDevicePath is retained. The newly created device path is returned.
80   If FirstDevicePath is NULL, then it is ignored, and a duplicate of SecondDevicePath is returned.
81   If SecondDevicePath is NULL, then it is ignored, and a duplicate of FirstDevicePath is returned.
82   If both FirstDevicePath and SecondDevicePath are NULL, then NULL is returned.
83   If there is not enough memory for the newly allocated buffer, then NULL is returned.
84   The memory for the new device path is allocated from EFI boot services memory. It is the
85   responsibility of the caller to free the memory allocated.
86 
87   @param  FirstDevicePath            A pointer to a device path data structure.
88   @param  SecondDevicePath           A pointer to a device path data structure.
89 
90   @return A pointer to the new device path.
91 
92 **/
93 EFI_DEVICE_PATH_PROTOCOL *
94 EFIAPI
95 GlueAppendDevicePath (
96   IN CONST EFI_DEVICE_PATH_PROTOCOL  *FirstDevicePath,  OPTIONAL
97   IN CONST EFI_DEVICE_PATH_PROTOCOL  *SecondDevicePath  OPTIONAL
98   );
99 
100 /**
101   Creates a new path by appending the device node to the device path.
102 
103   This function creates a new device path by appending a copy of the device node specified by
104   DevicePathNode to a copy of the device path specified by DevicePath in an allocated buffer.
105   The end-of-device-path device node is moved after the end of the appended device node.
106   If DevicePath is NULL, then NULL is returned.
107   If DevicePathNode is NULL, then NULL is returned.
108   If there is not enough memory to allocate space for the new device path, then NULL is returned.
109   The memory is allocated from EFI boot services memory. It is the responsibility of the caller to
110   free the memory allocated.
111 
112   @param  DevicePath                 A pointer to a device path data structure.
113   @param  DevicePathNode             A pointer to a single device path node.
114 
115   @return A pointer to the new device path.
116 
117 **/
118 EFI_DEVICE_PATH_PROTOCOL *
119 EFIAPI
120 GlueAppendDevicePathNode (
121   IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath,     OPTIONAL
122   IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePathNode  OPTIONAL
123   );
124 
125 /**
126   Creates a new device path by appending the specified device path instance to the specified device
127   path.
128 
129   This function creates a new device path by appending a copy of the device path instance specified
130   by DevicePathInstance to a copy of the device path secified by DevicePath in a allocated buffer.
131   The end-of-device-path device node is moved after the end of the appended device path instance
132   and a new end-of-device-path-instance node is inserted between.
133   If DevicePath is NULL, then a copy if DevicePathInstance is returned.
134   If DevicePathInstance is NULL, then NULL is returned.
135   If there is not enough memory to allocate space for the new device path, then NULL is returned.
136   The memory is allocated from EFI boot services memory. It is the responsibility of the caller to
137   free the memory allocated.
138 
139   @param  DevicePath                 A pointer to a device path data structure.
140   @param  DevicePathInstance         A pointer to a device path instance.
141 
142   @return A pointer to the new device path.
143 
144 **/
145 EFI_DEVICE_PATH_PROTOCOL *
146 EFIAPI
147 GlueAppendDevicePathInstance (
148   IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath,        OPTIONAL
149   IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePathInstance OPTIONAL
150   );
151 
152 /**
153   Creates a copy of the current device path instance and returns a pointer to the next device path
154   instance.
155 
156   This function creates a copy of the current device path instance. It also updates DevicePath to
157   point to the next device path instance in the device path (or NULL if no more) and updates Size
158   to hold the size of the device path instance copy.
159   If DevicePath is NULL, then NULL is returned.
160   If there is not enough memory to allocate space for the new device path, then NULL is returned.
161   The memory is allocated from EFI boot services memory. It is the responsibility of the caller to
162   free the memory allocated.
163   If Size is NULL, then ASSERT().
164 
165   @param  DevicePath                 On input, this holds the pointer to the current device path
166                                      instance. On output, this holds the pointer to the next device
167                                      path instance or NULL if there are no more device path
168                                      instances in the device path pointer to a device path data
169                                      structure.
170   @param  Size                       On output, this holds the size of the device path instance, in
171                                      bytes or zero, if DevicePath is NULL.
172 
173   @return A pointer to the current device path instance.
174 
175 **/
176 EFI_DEVICE_PATH_PROTOCOL *
177 EFIAPI
178 GlueGetNextDevicePathInstance (
179   IN OUT EFI_DEVICE_PATH_PROTOCOL    **DevicePath,
180   OUT UINTN                          *Size
181   );
182 
183 /**
184   Creates a copy of the current device path instance and returns a pointer to the next device path
185   instance.
186 
187   This function creates a new device node in a newly allocated buffer of size NodeLength and
188   initializes the device path node header with NodeType and NodeSubType.  The new device path node
189   is returned.
190   If NodeLength is smaller than a device path header, then NULL is returned.
191   If there is not enough memory to allocate space for the new device path, then NULL is returned.
192   The memory is allocated from EFI boot services memory. It is the responsibility of the caller to
193   free the memory allocated.
194 
195   @param  NodeType                   The device node type for the new device node.
196   @param  NodeSubType                The device node sub-type for the new device node.
197   @param  NodeLength                 The length of the new device node.
198 
199   @return The new device path.
200 
201 **/
202 EFI_DEVICE_PATH_PROTOCOL *
203 EFIAPI
204 CreateDeviceNode (
205   IN UINT8                           NodeType,
206   IN UINT8                           NodeSubType,
207   IN UINT16                          NodeLength
208   );
209 
210 /**
211   Determines if a device path is single or multi-instance.
212 
213   This function returns TRUE if the device path specified by DevicePath is multi-instance.
214   Otherwise, FALSE is returned.  If DevicePath is NULL, then FALSE is returned.
215 
216   @param  DevicePath                 A pointer to a device path data structure.
217 
218   @retval  TRUE                      DevicePath is multi-instance.
219   @retval  FALSE                     DevicePath is not multi-instance or DevicePath is NULL.
220 
221 **/
222 BOOLEAN
223 EFIAPI
224 GlueIsDevicePathMultiInstance (
225   IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath
226   );
227 
228 /**
229   Retrieves the device path protocol from a handle.
230 
231   This function returns the device path protocol from the handle specified by Handle.  If Handle is
232   NULL or Handle does not contain a device path protocol, then NULL is returned.
233 
234   @param  Handle                     The handle from which to retrieve the device path protocol.
235 
236   @return The device path protocol from the handle specified by Handle.
237 
238 **/
239 EFI_DEVICE_PATH_PROTOCOL *
240 EFIAPI
241 GlueDevicePathFromHandle (
242   IN EFI_HANDLE                      Handle
243   );
244 
245 /**
246   Allocates a device path for a file and appends it to an existing device path.
247 
248   If Device is a valid device handle that contains a device path protocol, then a device path for
249   the file specified by FileName  is allocated and appended to the device path associated with the
250   handle Device.  The allocated device path is returned.  If Device is NULL or Device is a handle
251   that does not support the device path protocol, then a device path containing a single device
252   path node for the file specified by FileName is allocated and returned.
253   If FileName is NULL, then ASSERT().
254 
255   @param  Device                     A pointer to a device handle.  This parameter is optional and
256                                      may be NULL.
257   @param  FileName                   A pointer to a Null-terminated Unicode string.
258 
259   @return The allocated device path.
260 
261 **/
262 EFI_DEVICE_PATH_PROTOCOL *
263 EFIAPI
264 GlueFileDevicePath (
265   IN EFI_HANDLE                      Device,     OPTIONAL
266   IN CONST CHAR16                    *FileName
267   );
268 
269 #endif
270