InOsEmuPkg/Library/ThunkProtocolList/ThunkProtocolList.c

   1 /** @file
   2   Emulator Thunk to abstract OS services from pure EFI code
   3
   4   Copyright (c) 2008 - 2011, Apple Inc. All rights reserved.<BR>
   5   Copyright (c) 2011, Intel Corporation. All rights reserved.<BR>
   6
   7   This program and the accompanying materials
   8   are licensed and made available under the terms and conditions of the BSD License
   9   which accompanies this distribution.  The full text of the license may be found at
  10   http://opensource.org/licenses/bsd-license.php
  11
  12   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #include <Uefi.h>
  18 #include <Library/BaseLib.h>
  19 #include <Library/BaseMemoryLib.h>
  20 #include <Library/DebugLib.h>
  21 #include <Library/MemoryAllocationLib.h>
  22
  23 #include <Protocol/EmuIoThunk.h>
  24
  25
  26 #define EMU_IO_THUNK_PROTOCOL_DATA_SIGNATURE SIGNATURE_32('E','m','u','T')
  27
  28 typedef struct {
  29   UINTN                 Signature;
  30   EMU_IO_THUNK_PROTOCOL Data;
  31   BOOLEAN               EmuBusDriver;
  32   LIST_ENTRY            Link;
  33 } EMU_IO_THUNK_PROTOCOL_DATA;
  34
  35 LIST_ENTRY  mThunkList = INITIALIZE_LIST_HEAD_VARIABLE (mThunkList);
  36
  37
  38 EFI_STATUS
  39 EFIAPI
  40 AddThunkProtocol (
  41   IN  EMU_IO_THUNK_PROTOCOL   *ThunkIo,
  42   IN  CHAR16                  *ConfigString,
  43   IN  BOOLEAN                 EmuBusDriver
  44   )
  45 {
  46   CHAR16                      *StartString;
  47   CHAR16                      *SubString;
  48   UINTN                       Instance;
  49   EMU_IO_THUNK_PROTOCOL_DATA  *Private;
  50
  51   if (ThunkIo == NULL) {
  52     return EFI_INVALID_PARAMETER;
  53   }
  54
  55   Instance = 0;
  56   StartString = AllocatePool (StrSize (ConfigString));
  57   StrCpy (StartString, ConfigString);
  58   while (*StartString != '\0') {
  59
  60     //
  61     // Find the end of the sub string
  62     //
  63     SubString = StartString;
  64     while (*SubString != '\0' && *SubString != '!') {
  65       SubString++;
  66     }
  67
  68     if (*SubString == '!') {
  69       //
  70       // Replace token with '\0' to make sub strings. If this is the end
  71       //  of the string SubString will already point to NULL.
  72       //
  73       *SubString = '\0';
  74       SubString++;
  75     }
  76
  77     Private = AllocatePool (sizeof (EMU_IO_THUNK_PROTOCOL_DATA));
  78     if (Private == NULL) {
  79       return EFI_OUT_OF_RESOURCES;
  80     }
  81     Private->Signature          = EMU_IO_THUNK_PROTOCOL_DATA_SIGNATURE;
  82     Private->EmuBusDriver       = EmuBusDriver;
  83
  84     CopyMem (&Private->Data, ThunkIo, sizeof (EMU_IO_THUNK_PROTOCOL));
  85     Private->Data.Instance      = Instance++;
  86     Private->Data.ConfigString  = StartString;
  87
  88     InsertTailList (&mThunkList, &Private->Link);
  89
  90     //
  91     // Parse Next sub string. This will point to '\0' if we are at the end.
  92     //
  93     StartString = SubString;
  94   }
  95
  96   return EFI_SUCCESS;
  97 }
  98
  99
 100 EFI_STATUS
 101 EFIAPI
 102 GetNextThunkProtocol (
 103   IN  BOOLEAN                 EmuBusDriver,
 104   OUT EMU_IO_THUNK_PROTOCOL   **Instance  OPTIONAL
 105   )
 106 {
 107   LIST_ENTRY                   *Link;
 108   EMU_IO_THUNK_PROTOCOL_DATA   *Private;
 109
 110   if (mThunkList.ForwardLink == &mThunkList) {
 111     // Skip parsing an empty list
 112     return EFI_NOT_FOUND;
 113   }
 114
 115   for (Link = mThunkList.ForwardLink; Link != &mThunkList; Link = Link->ForwardLink) {
 116     Private = CR (Link, EMU_IO_THUNK_PROTOCOL_DATA, Link, EMU_IO_THUNK_PROTOCOL_DATA_SIGNATURE);
 117     if (EmuBusDriver & !Private->EmuBusDriver) {
 118       continue;
 119     } else if (*Instance == NULL) {
 120       // Find 1st match in list
 121       *Instance = &Private->Data;
 122       return EFI_SUCCESS;
 123     } else if (*Instance == &Private->Data) {
 124       // Matched previous call so look for valid next entry
 125       Link = Link->ForwardLink;
 126       if (Link == &mThunkList) {
 127         return EFI_NOT_FOUND;
 128       }
 129       Private = CR (Link, EMU_IO_THUNK_PROTOCOL_DATA, Link, EMU_IO_THUNK_PROTOCOL_DATA_SIGNATURE);
 130       *Instance = &Private->Data;
 131       return EFI_SUCCESS;
 132     }
 133   }
 134
 135
 136   return EFI_NOT_FOUND;
 137 }
 138