StdLibPrivateInternalFiles/Include/Device/Device.h

   1 /** @file
   2   Device Abstraction Utility Routines
   3
   4   Copyright (c) 2011, Intel Corporation. All rights reserved.<BR>
   5   This program and the accompanying materials are licensed and made available
   6   under the terms and conditions of the BSD License which accompanies this
   7   distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php.
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13   Depends upon: <kfile.h>
  14 **/
  15 #ifndef __DEV_UTILITY_H__
  16 #define __DEV_UTILITY_H__
  17
  18 #define CON_COOKIE    0x62416F49    ///< 'IoAb'
  19
  20 typedef enum {
  21   PathAbsolute = 0,
  22   PathRelative,
  23   PathMapping,
  24   PathError
  25 } PATH_CLASS;
  26
  27 typedef struct _Device_Node {
  28   LIST_ENTRY        DevList;        ///< List of registered device abstractions
  29   const CHAR16     *DevName;
  30   const GUID       *DevProto;
  31   void             *InstanceList;   ///< Array of instances for this device
  32   FO_OPEN           OpenFunc;
  33   UINT32            InstanceSize;   ///< Size of each instance in the InstanceList
  34   UINT32            NumInstances;   ///< Number of instances in InstanceList
  35   UINT32            OpModes;        ///< Supported modes of operation
  36 } DeviceNode;
  37
  38 __BEGIN_DECLS
  39
  40 extern LIST_ENTRY       daDeviceList;     ///< List of registered devices.
  41 extern DeviceNode      *daDefaultDevice;  ///< Device to use if nothing else found
  42 extern DeviceNode      *daRootDevice;     ///< Device containing the root file system
  43 extern DeviceNode      *daCurrentDevice;  ///< Device currently being accessed
  44
  45 /** Add a new device to the device list.
  46
  47     @param  DevName       Name of the device to add.
  48     @param  DevProto      Pointer to the GUID identifying the protocol associated with this device.
  49                           If DevProto is NULL, startup code will not try to find instances
  50                           of this device.
  51     @param  OpenFunc      Pointer to the device's Open function.
  52     @param  InstanceList  Optional pointer to the device's initialized instance list.
  53                           If InstanceList is NULL, the application startup code will
  54                           scan for instances of the protocol identified by DevProto and
  55                           populate the InstanceList in the order those protocols are found.
  56     @param  NumInstance   Number of instances in InstanceList.
  57     @param  Modes         Bit-mapped flags indicating operations (R, W, RW, ...) permitted to this device.
  58
  59 **/
  60 DeviceNode * EFIAPI __DevRegister( const CHAR16 *DevName, GUID *DevProto, FO_OPEN OpenFunc,
  61                                    void *InstanceList, int NumInstance, UINT32 InstanceSize, UINT32 Modes);
  62
  63 /** Find a DeviceNode matching DevName or DevProto, or both.
  64
  65     If DevName is NULL, then the device name is not used in the search.
  66     If DevProto is NULL, then the protocol GUID is not used in the search.
  67     If both are NULL, then INVALID_PARAMETER is returned.
  68     If both DevName and DevProto are specified, then both must match.
  69     If both are specified but only one matches, then DEVICE_ERROR is returned.
  70
  71     @param  DevName     Name of the Device Abstraction to find.
  72     @param  DevProto    GUID of the Protocol associated with the Device Abstraction.
  73     @param  Node        Pointer to the pointer to receive the found Device Node's address.
  74
  75     @retval RETURN_SUCCESS              The desired Device Node was found.
  76     @retval RETURN_INVALID_PARAMETER    Both DevName and DevProto are NULL or Node is NULL.
  77     @retval RETURN_DEVICE_ERROR         One, but not both, of DevNode and DevProto matched.
  78 **/
  79 EFI_STATUS EFIAPI __DevSearch( CHAR16 *DevName, GUID *DevProto, DeviceNode **Node);
  80
  81 /** Identify the type of path pointed to by Path.
  82
  83     Paths are classified based upon their initial character sequences.
  84       ^\\       Absolute Path
  85       ^\.       Relative Path
  86       ^[^:\\]:  Mapping Path
  87       .*        Relative Path
  88
  89     Mapping paths are broken into two parts at the ':'.  The part to the left of the ':'
  90     is the Map Name, pointed to by Path, and the part to the right of the ':' is pointed
  91     to by NewPath.
  92
  93     If Path was not a Mapping Path, then NewPath is set to Path.
  94
  95     @param[in]    Path      Pointer to the path to be classified.
  96     @param[out]   NewPath   Pointer to the path portion of a mapping path.
  97
  98     @retval PathAbsolute  Path is an absolute path. NewPath points to the first '\'.
  99     @retval PathRelative  Path is a relative path. NewPath = Path.
 100     @retval PathMapping   Path is a mapping path.  NewPath points to the ':'.
 101     @retval PathError     Path is NULL.
 102 **/
 103 PATH_CLASS EFIAPI ClassifyPath(IN wchar_t *Path, OUT wchar_t **NewPath, int * const Length);
 104
 105 /*  Normalize a narrow-character path and produce a wide-character path
 106     that has forward slashes replaced with backslashes.
 107     Backslashes are directory separators in UEFI File Paths.
 108
 109     It is the caller's responsibility to eventually free() the returned buffer.
 110
 111     @param[in]    path    A pointer to the narrow-character path to be normalized.
 112
 113     @return     A pointer to a buffer containing the normalized, wide-character, path.
 114 */
 115 wchar_t *
 116 NormalizePath( const char *path);
 117
 118 /** Process a MBCS path returning the final absolute path and the target device.
 119
 120     @param path
 121     @param FullPath
 122     @param DevNode
 123
 124     @retval RETURN_SUCCESS
 125     @retval RETURN_INVALID_PARAMETER
 126     @retval RETURN_NOT_FOUND
 127 **/
 128 RETURN_STATUS
 129 EFIAPI
 130 ParsePath( const char *path, wchar_t **FullPath, DeviceNode **DevNode, int *Which);
 131
 132 /** Process a wide character string representing a Mapping Path and extract the instance number.
 133
 134     The instance number is the sequence of decimal digits immediately to the left
 135     of the ":" in the Map Name portion of a Mapping Path.
 136
 137     This function is called with a pointer to beginning of the Map Name.
 138     Thus Path[Length] must be a ':' and Path[Length - 1] must be a decimal digit.
 139     If either of these are not true, an instance value of 0 is returned.
 140
 141     If Path is NULL, an instance value of 0 is returned.
 142
 143     @param[in]  Path    Points to the beginning of a Mapping Path
 144     @param[in]  Length  Number of valid characters to the left of the ':'
 145
 146     @return   Returns either 0 or the value of the contiguous digits to the left of the ':'.
 147 **/
 148 int
 149 EFIAPI
 150 PathInstance( const wchar_t *Path, int length);
 151
 152 /** Transform a relative path into an absolute path.
 153
 154     If Path is NULL, return NULL.
 155     Otherwise, pre-pend the CWD to Path then process the resulting path to:
 156       - Replace "/./" with "/"
 157       - Replace "/<dirname>/../" with "/"
 158       - Do not allow one to back up past the root, "/"
 159
 160     Also sets the Current Working Device to the Root Device.
 161
 162     Path must be a previously allocated buffer.  PathAdjust will
 163     allocate a new buffer to hold the results of the transformation
 164     then free Path.  A pointer to the newly allocated buffer is returned.
 165
 166     @param[in]  Path    A pointer to the path to be transformed.  This buffer
 167                         will always be freed.
 168
 169     @return   A pointer to a buffer containing the transformed path.
 170 **/
 171 wchar_t *
 172 EFIAPI
 173 PathAdjust(wchar_t *Path);
 174
 175 /** Replace the leading portion of Path with any aliases.
 176
 177     Aliases are read from /etc/fstab.  If there is an associated device, the
 178     Current Working Device is set to that device.
 179
 180     Path must be a previously allocated buffer.  PathAlias will
 181     allocate a new buffer to hold the results of the transformation
 182     then free Path.  A pointer to the newly allocated buffer is returned.
 183
 184     @param[in]    Path    A pointer to the original, unaliased, path.  This
 185                           buffer is always freed.
 186     @param[out]   Node    Filled in with a pointer to the Device Node describing
 187                           the device abstraction associated with this path.
 188
 189     @return     A pointer to a buffer containing the aliased path.
 190 **/
 191 wchar_t *
 192 EFIAPI
 193 PathAlias(wchar_t *Path, DeviceNode **Node);
 194
 195 __END_DECLS
 196
 197 #endif  /* __DEV_UTILITY_H__ */