code.delx.au - refind/blob - refind/lib.c

   1 /*
   2  * refit/lib.c
   3  * General library functions
   4  *
   5  * Copyright (c) 2006-2009 Christoph Pfisterer
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions are
  10  * met:
  11  *
  12  *  * Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  *  * Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the
  18  *    distribution.
  19  *
  20  *  * Neither the name of Christoph Pfisterer nor the names of the
  21  *    contributors may be used to endorse or promote products derived
  22  *    from this software without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  25  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  26  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  27  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  28  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  29  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  30  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  31  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  34  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  */
  36 /*
  37  * Modifications copyright (c) 2012 Roderick W. Smith
  38  *
  39  * Modifications distributed under the terms of the GNU General Public
  40  * License (GPL) version 3 (GPLv3), a copy of which must be distributed
  41  * with this source code or binaries made from it.
  42  *
  43  */
  44
  45 #include "global.h"
  46 #include "lib.h"
  47 #include "icns.h"
  48 #include "screen.h"
  49 #include "refit_call_wrapper.h"
  50
  51 // variables
  52
  53 EFI_HANDLE       SelfImageHandle;
  54 EFI_LOADED_IMAGE *SelfLoadedImage;
  55 EFI_FILE         *SelfRootDir;
  56 EFI_FILE         *SelfDir;
  57 CHAR16           *SelfDirPath;
  58
  59 REFIT_VOLUME     *SelfVolume = NULL;
  60 REFIT_VOLUME     **Volumes = NULL;
  61 UINTN            VolumesCount = 0;
  62
  63 // Maximum size for disk sectors
  64 #define SECTOR_SIZE 4096
  65
  66 // functions
  67
  68 static EFI_STATUS FinishInitRefitLib(VOID);
  69
  70 static VOID UninitVolumes(VOID);
  71
  72 //
  73 // self recognition stuff
  74 //
  75
  76 EFI_STATUS InitRefitLib(IN EFI_HANDLE ImageHandle)
  77 {
  78     EFI_STATUS  Status;
  79     CHAR16      *DevicePathAsString;
  80     CHAR16      BaseDirectory[256];
  81     UINTN       i;
  82
  83     SelfImageHandle = ImageHandle;
  84     Status = refit_call3_wrapper(BS->HandleProtocol, SelfImageHandle, &LoadedImageProtocol, (VOID **) &SelfLoadedImage);
  85     if (CheckFatalError(Status, L"while getting a LoadedImageProtocol handle"))
  86         return EFI_LOAD_ERROR;
  87
  88     // find the current directory
  89     DevicePathAsString = DevicePathToStr(SelfLoadedImage->FilePath);
  90     if (DevicePathAsString != NULL) {
  91         StrCpy(BaseDirectory, DevicePathAsString);
  92         FreePool(DevicePathAsString);
  93         for (i = StrLen(BaseDirectory); i > 0 && BaseDirectory[i] != '\\'; i--) ;
  94         BaseDirectory[i] = 0;
  95     } else
  96         BaseDirectory[0] = 0;
  97     SelfDirPath = StrDuplicate(BaseDirectory);
  98
  99     return FinishInitRefitLib();
 100 }
 101
 102 // called before running external programs to close open file handles
 103 VOID UninitRefitLib(VOID)
 104 {
 105     UninitVolumes();
 106
 107     if (SelfDir != NULL) {
 108         refit_call1_wrapper(SelfDir->Close, SelfDir);
 109         SelfDir = NULL;
 110     }
 111
 112     if (SelfRootDir != NULL) {
 113         refit_call1_wrapper(SelfRootDir->Close, SelfRootDir);
 114         SelfRootDir = NULL;
 115     }
 116 }
 117
 118 // called after running external programs to re-open file handles
 119 EFI_STATUS ReinitRefitLib(VOID)
 120 {
 121     ReinitVolumes();
 122
 123     if (SelfVolume != NULL && SelfVolume->RootDir != NULL)
 124         SelfRootDir = SelfVolume->RootDir;
 125
 126     return FinishInitRefitLib();
 127 }
 128
 129 static EFI_STATUS FinishInitRefitLib(VOID)
 130 {
 131     EFI_STATUS  Status;
 132
 133     if (SelfRootDir == NULL) {
 134         SelfRootDir = LibOpenRoot(SelfLoadedImage->DeviceHandle);
 135         if (SelfRootDir == NULL) {
 136             CheckError(EFI_LOAD_ERROR, L"while (re)opening our installation volume");
 137             return EFI_LOAD_ERROR;
 138         }
 139     }
 140
 141     Status = refit_call5_wrapper(SelfRootDir->Open, SelfRootDir, &SelfDir, SelfDirPath, EFI_FILE_MODE_READ, 0);
 142     if (CheckFatalError(Status, L"while opening our installation directory"))
 143         return EFI_LOAD_ERROR;
 144
 145     return EFI_SUCCESS;
 146 }
 147
 148 //
 149 // list functions
 150 //
 151
 152 VOID CreateList(OUT VOID ***ListPtr, OUT UINTN *ElementCount, IN UINTN InitialElementCount)
 153 {
 154     UINTN AllocateCount;
 155
 156     *ElementCount = InitialElementCount;
 157     if (*ElementCount > 0) {
 158         AllocateCount = (*ElementCount + 7) & ~7;   // next multiple of 8
 159         *ListPtr = AllocatePool(sizeof(VOID *) * AllocateCount);
 160     } else {
 161         *ListPtr = NULL;
 162     }
 163 }
 164
 165 VOID AddListElement(IN OUT VOID ***ListPtr, IN OUT UINTN *ElementCount, IN VOID *NewElement)
 166 {
 167     UINTN AllocateCount;
 168
 169     if ((*ElementCount & 7) == 0) {
 170         AllocateCount = *ElementCount + 8;
 171         if (*ElementCount == 0)
 172             *ListPtr = AllocatePool(sizeof(VOID *) * AllocateCount);
 173         else
 174             *ListPtr = ReallocatePool(*ListPtr, sizeof(VOID *) * (*ElementCount), sizeof(VOID *) * AllocateCount);
 175     }
 176     (*ListPtr)[*ElementCount] = NewElement;
 177     (*ElementCount)++;
 178 } /* VOID AddListElement() */
 179
 180 VOID FreeList(IN OUT VOID ***ListPtr, IN OUT UINTN *ElementCount)
 181 {
 182     UINTN i;
 183
 184     if (*ElementCount > 0) {
 185         for (i = 0; i < *ElementCount; i++) {
 186             // TODO: call a user-provided routine for each element here
 187             FreePool((*ListPtr)[i]);
 188         }
 189         FreePool(*ListPtr);
 190     }
 191 }
 192
 193 //
 194 // firmware device path discovery
 195 //
 196
 197 static UINT8 LegacyLoaderMediaPathData[] = {
 198     0x04, 0x06, 0x14, 0x00, 0xEB, 0x85, 0x05, 0x2B,
 199     0xB8, 0xD8, 0xA9, 0x49, 0x8B, 0x8C, 0xE2, 0x1B,
 200     0x01, 0xAE, 0xF2, 0xB7, 0x7F, 0xFF, 0x04, 0x00,
 201 };
 202 static EFI_DEVICE_PATH *LegacyLoaderMediaPath = (EFI_DEVICE_PATH *)LegacyLoaderMediaPathData;
 203
 204 VOID ExtractLegacyLoaderPaths(EFI_DEVICE_PATH **PathList, UINTN MaxPaths, EFI_DEVICE_PATH **HardcodedPathList)
 205 {
 206     EFI_STATUS          Status;
 207     UINTN               HandleCount = 0;
 208     UINTN               HandleIndex, HardcodedIndex;
 209     EFI_HANDLE          *Handles;
 210     EFI_HANDLE          Handle;
 211     UINTN               PathCount = 0;
 212     UINTN               PathIndex;
 213     EFI_LOADED_IMAGE    *LoadedImage;
 214     EFI_DEVICE_PATH     *DevicePath;
 215     BOOLEAN             Seen;
 216
 217     MaxPaths--;  // leave space for the terminating NULL pointer
 218
 219     // get all LoadedImage handles
 220     Status = LibLocateHandle(ByProtocol, &LoadedImageProtocol, NULL,
 221                              &HandleCount, &Handles);
 222     if (CheckError(Status, L"while listing LoadedImage handles")) {
 223         if (HardcodedPathList) {
 224             for (HardcodedIndex = 0; HardcodedPathList[HardcodedIndex] && PathCount < MaxPaths; HardcodedIndex++)
 225                 PathList[PathCount++] = HardcodedPathList[HardcodedIndex];
 226         }
 227         PathList[PathCount] = NULL;
 228         return;
 229     }
 230     for (HandleIndex = 0; HandleIndex < HandleCount && PathCount < MaxPaths; HandleIndex++) {
 231         Handle = Handles[HandleIndex];
 232
 233         Status = refit_call3_wrapper(BS->HandleProtocol, Handle, &LoadedImageProtocol, (VOID **) &LoadedImage);
 234         if (EFI_ERROR(Status))
 235             continue;  // This can only happen if the firmware scewed up, ignore it.
 236
 237         Status = refit_call3_wrapper(BS->HandleProtocol, LoadedImage->DeviceHandle, &DevicePathProtocol, (VOID **) &DevicePath);
 238         if (EFI_ERROR(Status))
 239             continue;  // This happens, ignore it.
 240
 241         // Only grab memory range nodes
 242         if (DevicePathType(DevicePath) != HARDWARE_DEVICE_PATH || DevicePathSubType(DevicePath) != HW_MEMMAP_DP)
 243             continue;
 244
 245         // Check if we have this device path in the list already
 246         // WARNING: This assumes the first node in the device path is unique!
 247         Seen = FALSE;
 248         for (PathIndex = 0; PathIndex < PathCount; PathIndex++) {
 249             if (DevicePathNodeLength(DevicePath) != DevicePathNodeLength(PathList[PathIndex]))
 250                 continue;
 251             if (CompareMem(DevicePath, PathList[PathIndex], DevicePathNodeLength(DevicePath)) == 0) {
 252                 Seen = TRUE;
 253                 break;
 254             }
 255         }
 256         if (Seen)
 257             continue;
 258
 259         PathList[PathCount++] = AppendDevicePath(DevicePath, LegacyLoaderMediaPath);
 260     }
 261     FreePool(Handles);
 262
 263     if (HardcodedPathList) {
 264         for (HardcodedIndex = 0; HardcodedPathList[HardcodedIndex] && PathCount < MaxPaths; HardcodedIndex++)
 265             PathList[PathCount++] = HardcodedPathList[HardcodedIndex];
 266     }
 267     PathList[PathCount] = NULL;
 268 }
 269
 270 //
 271 // volume functions
 272 //
 273
 274 static VOID ScanVolumeBootcode(IN OUT REFIT_VOLUME *Volume, OUT BOOLEAN *Bootable)
 275 {
 276     EFI_STATUS              Status;
 277     UINT8                   SectorBuffer[SECTOR_SIZE];
 278     UINTN                   i;
 279     MBR_PARTITION_INFO      *MbrTable;
 280     BOOLEAN                 MbrTableFound;
 281
 282     Volume->HasBootCode = FALSE;
 283     Volume->OSIconName = NULL;
 284     Volume->OSName = NULL;
 285     *Bootable = FALSE;
 286
 287     if (Volume->BlockIO == NULL)
 288         return;
 289     if (Volume->BlockIO->Media->BlockSize > SECTOR_SIZE)
 290         return;   // our buffer is too small...
 291
 292     // look at the boot sector (this is used for both hard disks and El Torito images!)
 293     Status = refit_call5_wrapper(Volume->BlockIO->ReadBlocks,
 294                                  Volume->BlockIO, Volume->BlockIO->Media->MediaId,
 295                                  Volume->BlockIOOffset, SECTOR_SIZE, SectorBuffer);
 296     if (!EFI_ERROR(Status)) {
 297
 298         if (*((UINT16 *)(SectorBuffer + 510)) == 0xaa55 && SectorBuffer[0] != 0) {
 299             *Bootable = TRUE;
 300             Volume->HasBootCode = TRUE;
 301         }
 302
 303         // detect specific boot codes
 304         if (CompareMem(SectorBuffer + 2, "LILO", 4) == 0 ||
 305             CompareMem(SectorBuffer + 6, "LILO", 4) == 0 ||
 306             CompareMem(SectorBuffer + 3, "SYSLINUX", 8) == 0 ||
 307             FindMem(SectorBuffer, SECTOR_SIZE, "ISOLINUX", 8) >= 0) {
 308             Volume->HasBootCode = TRUE;
 309             Volume->OSIconName = L"linux";
 310             Volume->OSName = L"Linux";
 311
 312         } else if (FindMem(SectorBuffer, 512, "Geom\0Hard Disk\0Read\0 Error", 26) >= 0) {   // GRUB
 313             Volume->HasBootCode = TRUE;
 314             Volume->OSIconName = L"grub,linux";
 315             Volume->OSName = L"Linux";
 316
 317         } else if ((*((UINT32 *)(SectorBuffer + 502)) == 0 &&
 318                     *((UINT32 *)(SectorBuffer + 506)) == 50000 &&
 319                     *((UINT16 *)(SectorBuffer + 510)) == 0xaa55) ||
 320                     FindMem(SectorBuffer, SECTOR_SIZE, "Starting the BTX loader", 23) >= 0) {
 321             Volume->HasBootCode = TRUE;
 322             Volume->OSIconName = L"freebsd";
 323             Volume->OSName = L"FreeBSD";
 324
 325         } else if (FindMem(SectorBuffer, 512, "!Loading", 8) >= 0 ||
 326                    FindMem(SectorBuffer, SECTOR_SIZE, "/cdboot\0/CDBOOT\0", 16) >= 0) {
 327             Volume->HasBootCode = TRUE;
 328             Volume->OSIconName = L"openbsd";
 329             Volume->OSName = L"OpenBSD";
 330
 331         } else if (FindMem(SectorBuffer, 512, "Not a bootxx image", 18) >= 0 ||
 332                    *((UINT32 *)(SectorBuffer + 1028)) == 0x7886b6d1) {
 333             Volume->HasBootCode = TRUE;
 334             Volume->OSIconName = L"netbsd";
 335             Volume->OSName = L"NetBSD";
 336
 337         } else if (FindMem(SectorBuffer, SECTOR_SIZE, "NTLDR", 5) >= 0) {
 338             Volume->HasBootCode = TRUE;
 339             Volume->OSIconName = L"win";
 340             Volume->OSName = L"Windows";
 341
 342         } else if (FindMem(SectorBuffer, SECTOR_SIZE, "BOOTMGR", 7) >= 0) {
 343             Volume->HasBootCode = TRUE;
 344             Volume->OSIconName = L"winvista,win";
 345             Volume->OSName = L"Windows";
 346
 347         } else if (FindMem(SectorBuffer, 512, "CPUBOOT SYS", 11) >= 0 ||
 348                    FindMem(SectorBuffer, 512, "KERNEL  SYS", 11) >= 0) {
 349             Volume->HasBootCode = TRUE;
 350             Volume->OSIconName = L"freedos";
 351             Volume->OSName = L"FreeDOS";
 352
 353         } else if (FindMem(SectorBuffer, 512, "OS2LDR", 6) >= 0 ||
 354                    FindMem(SectorBuffer, 512, "OS2BOOT", 7) >= 0) {
 355             Volume->HasBootCode = TRUE;
 356             Volume->OSIconName = L"ecomstation";
 357             Volume->OSName = L"eComStation";
 358
 359         } else if (FindMem(SectorBuffer, 512, "Be Boot Loader", 14) >= 0) {
 360             Volume->HasBootCode = TRUE;
 361             Volume->OSIconName = L"beos";
 362             Volume->OSName = L"BeOS";
 363
 364         } else if (FindMem(SectorBuffer, 512, "yT Boot Loader", 14) >= 0) {
 365             Volume->HasBootCode = TRUE;
 366             Volume->OSIconName = L"zeta,beos";
 367             Volume->OSName = L"ZETA";
 368
 369         } else if (FindMem(SectorBuffer, 512, "\x04" "beos\x06" "system\x05" "zbeos", 18) >= 0 ||
 370                    FindMem(SectorBuffer, 512, "\x06" "system\x0c" "haiku_loader", 20) >= 0) {
 371             Volume->HasBootCode = TRUE;
 372             Volume->OSIconName = L"haiku,beos";
 373             Volume->OSName = L"Haiku";
 374
 375         }
 376
 377         // NOTE: If you add an operating system with a name that starts with 'W' or 'L', you
 378         //  need to fix AddLegacyEntry in main.c.
 379
 380 #if REFIT_DEBUG > 0
 381         Print(L"  Result of bootcode detection: %s %s (%s)\n",
 382               Volume->HasBootCode ? L"bootable" : L"non-bootable",
 383               Volume->OSName, Volume->OSIconName);
 384 #endif
 385
 386         if (FindMem(SectorBuffer, 512, "Non-system disk", 15) >= 0)   // dummy FAT boot sector
 387             Volume->HasBootCode = FALSE;
 388
 389         // check for MBR partition table
 390         if (*((UINT16 *)(SectorBuffer + 510)) == 0xaa55) {
 391             MbrTableFound = FALSE;
 392             MbrTable = (MBR_PARTITION_INFO *)(SectorBuffer + 446);
 393             for (i = 0; i < 4; i++)
 394                 if (MbrTable[i].StartLBA && MbrTable[i].Size)
 395                     MbrTableFound = TRUE;
 396             for (i = 0; i < 4; i++)
 397                 if (MbrTable[i].Flags != 0x00 && MbrTable[i].Flags != 0x80)
 398                     MbrTableFound = FALSE;
 399             if (MbrTableFound) {
 400                 Volume->MbrPartitionTable = AllocatePool(4 * 16);
 401                 CopyMem(Volume->MbrPartitionTable, MbrTable, 4 * 16);
 402             }
 403         }
 404
 405     } else {
 406 #if REFIT_DEBUG > 0
 407         CheckError(Status, L"while reading boot sector");
 408 #endif
 409     }
 410 }
 411
 412 // default volume icon based on disk kind
 413 static VOID ScanVolumeDefaultIcon(IN OUT REFIT_VOLUME *Volume)
 414 {
 415     switch (Volume->DiskKind) {
 416        case DISK_KIND_INTERNAL:
 417           Volume->VolBadgeImage = BuiltinIcon(BUILTIN_ICON_VOL_INTERNAL);
 418           break;
 419        case DISK_KIND_EXTERNAL:
 420           Volume->VolBadgeImage = BuiltinIcon(BUILTIN_ICON_VOL_EXTERNAL);
 421           break;
 422        case DISK_KIND_OPTICAL:
 423           Volume->VolBadgeImage = BuiltinIcon(BUILTIN_ICON_VOL_OPTICAL);
 424           break;
 425     } // switch()
 426 }
 427
 428 static VOID ScanVolume(IN OUT REFIT_VOLUME *Volume)
 429 {
 430     EFI_STATUS              Status;
 431     EFI_DEVICE_PATH         *DevicePath, *NextDevicePath;
 432     EFI_DEVICE_PATH         *DiskDevicePath, *RemainingDevicePath;
 433     EFI_HANDLE              WholeDiskHandle;
 434     UINTN                   PartialLength;
 435     EFI_FILE_SYSTEM_INFO    *FileSystemInfoPtr;
 436     BOOLEAN                 Bootable;
 437
 438     // get device path
 439     Volume->DevicePath = DuplicateDevicePath(DevicePathFromHandle(Volume->DeviceHandle));
 440 #if REFIT_DEBUG > 0
 441     if (Volume->DevicePath != NULL) {
 442         Print(L"* %s\n", DevicePathToStr(Volume->DevicePath));
 443 #if REFIT_DEBUG >= 2
 444         DumpHex(1, 0, DevicePathSize(Volume->DevicePath), Volume->DevicePath);
 445 #endif
 446     }
 447 #endif
 448
 449     Volume->DiskKind = DISK_KIND_INTERNAL;  // default
 450
 451     // get block i/o
 452     Status = refit_call3_wrapper(BS->HandleProtocol, Volume->DeviceHandle, &BlockIoProtocol, (VOID **) &(Volume->BlockIO));
 453     if (EFI_ERROR(Status)) {
 454         Volume->BlockIO = NULL;
 455         Print(L"Warning: Can't get BlockIO protocol.\n");
 456     } else {
 457         if (Volume->BlockIO->Media->BlockSize == 2048)
 458             Volume->DiskKind = DISK_KIND_OPTICAL;
 459     }
 460
 461     // scan for bootcode and MBR table
 462     Bootable = FALSE;
 463     ScanVolumeBootcode(Volume, &Bootable);
 464
 465     // detect device type
 466     DevicePath = Volume->DevicePath;
 467     while (DevicePath != NULL && !IsDevicePathEndType(DevicePath)) {
 468         NextDevicePath = NextDevicePathNode(DevicePath);
 469
 470         if (DevicePathType(DevicePath) == MESSAGING_DEVICE_PATH &&
 471             (DevicePathSubType(DevicePath) == MSG_USB_DP ||
 472              DevicePathSubType(DevicePath) == MSG_USB_CLASS_DP ||
 473              DevicePathSubType(DevicePath) == MSG_1394_DP ||
 474              DevicePathSubType(DevicePath) == MSG_FIBRECHANNEL_DP))
 475             Volume->DiskKind = DISK_KIND_EXTERNAL;    // USB/FireWire/FC device -> external
 476         if (DevicePathType(DevicePath) == MEDIA_DEVICE_PATH &&
 477             DevicePathSubType(DevicePath) == MEDIA_CDROM_DP) {
 478             Volume->DiskKind = DISK_KIND_OPTICAL;     // El Torito entry -> optical disk
 479             Bootable = TRUE;
 480         }
 481
 482         if (DevicePathType(DevicePath) == MEDIA_DEVICE_PATH && DevicePathSubType(DevicePath) == MEDIA_VENDOR_DP) {
 483             Volume->IsAppleLegacy = TRUE;             // legacy BIOS device entry
 484             // TODO: also check for Boot Camp GUID
 485             Bootable = FALSE;   // this handle's BlockIO is just an alias for the whole device
 486         }
 487
 488         if (DevicePathType(DevicePath) == MESSAGING_DEVICE_PATH) {
 489             // make a device path for the whole device
 490             PartialLength = (UINT8 *)NextDevicePath - (UINT8 *)(Volume->DevicePath);
 491             DiskDevicePath = (EFI_DEVICE_PATH *)AllocatePool(PartialLength + sizeof(EFI_DEVICE_PATH));
 492             CopyMem(DiskDevicePath, Volume->DevicePath, PartialLength);
 493             CopyMem((UINT8 *)DiskDevicePath + PartialLength, EndDevicePath, sizeof(EFI_DEVICE_PATH));
 494
 495             // get the handle for that path
 496             RemainingDevicePath = DiskDevicePath;
 497             //Print(L"  * looking at %s\n", DevicePathToStr(RemainingDevicePath));
 498             Status = refit_call3_wrapper(BS->LocateDevicePath, &BlockIoProtocol, &RemainingDevicePath, &WholeDiskHandle);
 499             //Print(L"  * remaining: %s\n", DevicePathToStr(RemainingDevicePath));
 500             FreePool(DiskDevicePath);
 501
 502             if (!EFI_ERROR(Status)) {
 503                 //Print(L"  - original handle: %08x - disk handle: %08x\n", (UINT32)DeviceHandle, (UINT32)WholeDiskHandle);
 504
 505                 // get the device path for later
 506                 Status = refit_call3_wrapper(BS->HandleProtocol, WholeDiskHandle, &DevicePathProtocol, (VOID **) &DiskDevicePath);
 507                 if (!EFI_ERROR(Status)) {
 508                     Volume->WholeDiskDevicePath = DuplicateDevicePath(DiskDevicePath);
 509                 }
 510
 511                 // look at the BlockIO protocol
 512                 Status = refit_call3_wrapper(BS->HandleProtocol, WholeDiskHandle, &BlockIoProtocol, (VOID **) &Volume->WholeDiskBlockIO);
 513                 if (!EFI_ERROR(Status)) {
 514
 515                     // check the media block size
 516                     if (Volume->WholeDiskBlockIO->Media->BlockSize == 2048)
 517                         Volume->DiskKind = DISK_KIND_OPTICAL;
 518
 519                 } else {
 520                     Volume->WholeDiskBlockIO = NULL;
 521                     //CheckError(Status, L"from HandleProtocol");
 522                 }
 523             } //else
 524               //  CheckError(Status, L"from LocateDevicePath");
 525         }
 526
 527         DevicePath = NextDevicePath;
 528     } // while
 529
 530     if (!Bootable) {
 531 #if REFIT_DEBUG > 0
 532         if (Volume->HasBootCode)
 533             Print(L"  Volume considered non-bootable, but boot code is present\n");
 534 #endif
 535         Volume->HasBootCode = FALSE;
 536     }
 537
 538     // default volume icon based on disk kind
 539     ScanVolumeDefaultIcon(Volume);
 540
 541     // open the root directory of the volume
 542     Volume->RootDir = LibOpenRoot(Volume->DeviceHandle);
 543     if (Volume->RootDir == NULL) {
 544         return;
 545     }
 546
 547     // get volume name
 548     FileSystemInfoPtr = LibFileSystemInfo(Volume->RootDir);
 549     if (FileSystemInfoPtr != NULL) {
 550         Volume->VolName = StrDuplicate(FileSystemInfoPtr->VolumeLabel);
 551         FreePool(FileSystemInfoPtr);
 552     }
 553
 554     // TODO: if no official volume name is found or it is empty, use something else, e.g.:
 555     //   - name from bytes 3 to 10 of the boot sector
 556     //   - partition number
 557     //   - name derived from file system type or partition type
 558
 559     // get custom volume icon if present
 560     if (FileExists(Volume->RootDir, L".VolumeIcon.icns"))
 561         Volume->VolBadgeImage = LoadIcns(Volume->RootDir, L".VolumeIcon.icns", 32);
 562 }
 563
 564 static VOID ScanExtendedPartition(REFIT_VOLUME *WholeDiskVolume, MBR_PARTITION_INFO *MbrEntry)
 565 {
 566     EFI_STATUS              Status;
 567     REFIT_VOLUME            *Volume;
 568     UINT32                  ExtBase, ExtCurrent, NextExtCurrent;
 569     UINTN                   i;
 570     UINTN                   LogicalPartitionIndex = 4;
 571     UINT8                   SectorBuffer[512];
 572     BOOLEAN                 Bootable;
 573     MBR_PARTITION_INFO      *EMbrTable;
 574
 575     ExtBase = MbrEntry->StartLBA;
 576
 577     for (ExtCurrent = ExtBase; ExtCurrent; ExtCurrent = NextExtCurrent) {
 578         // read current EMBR
 579       Status = refit_call5_wrapper(WholeDiskVolume->BlockIO->ReadBlocks,
 580                                    WholeDiskVolume->BlockIO,
 581                                    WholeDiskVolume->BlockIO->Media->MediaId,
 582                                    ExtCurrent, 512, SectorBuffer);
 583         if (EFI_ERROR(Status))
 584             break;
 585         if (*((UINT16 *)(SectorBuffer + 510)) != 0xaa55)
 586             break;
 587         EMbrTable = (MBR_PARTITION_INFO *)(SectorBuffer + 446);
 588
 589         // scan logical partitions in this EMBR
 590         NextExtCurrent = 0;
 591         for (i = 0; i < 4; i++) {
 592             if ((EMbrTable[i].Flags != 0x00 && EMbrTable[i].Flags != 0x80) ||
 593                 EMbrTable[i].StartLBA == 0 || EMbrTable[i].Size == 0)
 594                 break;
 595             if (IS_EXTENDED_PART_TYPE(EMbrTable[i].Type)) {
 596                 // set next ExtCurrent
 597                 NextExtCurrent = ExtBase + EMbrTable[i].StartLBA;
 598                 break;
 599             } else {
 600
 601                 // found a logical partition
 602                 Volume = AllocateZeroPool(sizeof(REFIT_VOLUME));
 603                 Volume->DiskKind = WholeDiskVolume->DiskKind;
 604                 Volume->IsMbrPartition = TRUE;
 605                 Volume->MbrPartitionIndex = LogicalPartitionIndex++;
 606                 Volume->VolName = PoolPrint(L"Partition %d", Volume->MbrPartitionIndex + 1);
 607                 Volume->BlockIO = WholeDiskVolume->BlockIO;
 608                 Volume->BlockIOOffset = ExtCurrent + EMbrTable[i].StartLBA;
 609                 Volume->WholeDiskBlockIO = WholeDiskVolume->BlockIO;
 610
 611                 Bootable = FALSE;
 612                 ScanVolumeBootcode(Volume, &Bootable);
 613                 if (!Bootable)
 614                     Volume->HasBootCode = FALSE;
 615
 616                 ScanVolumeDefaultIcon(Volume);
 617
 618                 AddListElement((VOID ***) &Volumes, &VolumesCount, Volume);
 619
 620             }
 621         }
 622     }
 623 }
 624
 625 VOID ScanVolumes(VOID)
 626 {
 627     EFI_STATUS              Status;
 628     UINTN                   HandleCount = 0;
 629     UINTN                   HandleIndex;
 630     EFI_HANDLE              *Handles;
 631     REFIT_VOLUME            *Volume, *WholeDiskVolume;
 632     UINTN                   VolumeIndex, VolumeIndex2;
 633     MBR_PARTITION_INFO      *MbrTable;
 634     UINTN                   PartitionIndex;
 635     UINT8                   *SectorBuffer1, *SectorBuffer2;
 636     UINTN                   SectorSum, i;
 637
 638     FreePool(Volumes);
 639     Volumes = NULL;
 640     VolumesCount = 0;
 641
 642     // get all filesystem handles
 643     Status = LibLocateHandle(ByProtocol, &BlockIoProtocol, NULL, &HandleCount, &Handles);
 644     // was: &FileSystemProtocol
 645     if (Status == EFI_NOT_FOUND)
 646         return;  // no filesystems. strange, but true...
 647     if (CheckError(Status, L"while listing all file systems"))
 648         return;
 649
 650     // first pass: collect information about all handles
 651     for (HandleIndex = 0; HandleIndex < HandleCount; HandleIndex++) {
 652         Volume = AllocateZeroPool(sizeof(REFIT_VOLUME));
 653         Volume->DeviceHandle = Handles[HandleIndex];
 654         ScanVolume(Volume);
 655
 656         AddListElement((VOID ***) &Volumes, &VolumesCount, Volume);
 657
 658         if (Volume->DeviceHandle == SelfLoadedImage->DeviceHandle)
 659             SelfVolume = Volume;
 660     }
 661     FreePool(Handles);
 662
 663     if (SelfVolume == NULL)
 664         Print(L"WARNING: SelfVolume not found");
 665
 666     // second pass: relate partitions and whole disk devices
 667     for (VolumeIndex = 0; VolumeIndex < VolumesCount; VolumeIndex++) {
 668         Volume = Volumes[VolumeIndex];
 669         // check MBR partition table for extended partitions
 670         if (Volume->BlockIO != NULL && Volume->WholeDiskBlockIO != NULL &&
 671             Volume->BlockIO == Volume->WholeDiskBlockIO && Volume->BlockIOOffset == 0 &&
 672             Volume->MbrPartitionTable != NULL) {
 673             MbrTable = Volume->MbrPartitionTable;
 674             for (PartitionIndex = 0; PartitionIndex < 4; PartitionIndex++) {
 675                 if (IS_EXTENDED_PART_TYPE(MbrTable[PartitionIndex].Type)) {
 676                    ScanExtendedPartition(Volume, MbrTable + PartitionIndex);
 677                 }
 678             }
 679         }
 680
 681         // search for corresponding whole disk volume entry
 682         WholeDiskVolume = NULL;
 683         if (Volume->BlockIO != NULL && Volume->WholeDiskBlockIO != NULL &&
 684             Volume->BlockIO != Volume->WholeDiskBlockIO) {
 685             for (VolumeIndex2 = 0; VolumeIndex2 < VolumesCount; VolumeIndex2++) {
 686                 if (Volumes[VolumeIndex2]->BlockIO == Volume->WholeDiskBlockIO &&
 687                     Volumes[VolumeIndex2]->BlockIOOffset == 0)
 688                     WholeDiskVolume = Volumes[VolumeIndex2];
 689             }
 690         }
 691
 692         if (WholeDiskVolume != NULL && WholeDiskVolume->MbrPartitionTable != NULL) {
 693             // check if this volume is one of the partitions in the table
 694             MbrTable = WholeDiskVolume->MbrPartitionTable;
 695             SectorBuffer1 = AllocatePool(512);
 696             SectorBuffer2 = AllocatePool(512);
 697             for (PartitionIndex = 0; PartitionIndex < 4; PartitionIndex++) {
 698                 // check size
 699                 if ((UINT64)(MbrTable[PartitionIndex].Size) != Volume->BlockIO->Media->LastBlock + 1)
 700                     continue;
 701
 702                 // compare boot sector read through offset vs. directly
 703                 Status = refit_call5_wrapper(Volume->BlockIO->ReadBlocks,
 704                                              Volume->BlockIO, Volume->BlockIO->Media->MediaId,
 705                                              Volume->BlockIOOffset, 512, SectorBuffer1);
 706                 if (EFI_ERROR(Status))
 707                     break;
 708                 Status = refit_call5_wrapper(Volume->WholeDiskBlockIO->ReadBlocks,
 709                                              Volume->WholeDiskBlockIO, Volume->WholeDiskBlockIO->Media->MediaId,
 710                                              MbrTable[PartitionIndex].StartLBA, 512, SectorBuffer2);
 711                 if (EFI_ERROR(Status))
 712                     break;
 713                 if (CompareMem(SectorBuffer1, SectorBuffer2, 512) != 0)
 714                     continue;
 715                 SectorSum = 0;
 716                 for (i = 0; i < 512; i++)
 717                     SectorSum += SectorBuffer1[i];
 718                 if (SectorSum < 1000)
 719                     continue;
 720
 721                 // TODO: mark entry as non-bootable if it is an extended partition
 722
 723                 // now we're reasonably sure the association is correct...
 724                 Volume->IsMbrPartition = TRUE;
 725                 Volume->MbrPartitionIndex = PartitionIndex;
 726                 if (Volume->VolName == NULL)
 727                     Volume->VolName = PoolPrint(L"Partition %d", PartitionIndex + 1);
 728                 break;
 729             }
 730
 731             FreePool(SectorBuffer1);
 732             FreePool(SectorBuffer2);
 733         }
 734
 735     }
 736 } /* VOID ScanVolumes() */
 737
 738 static VOID UninitVolumes(VOID)
 739 {
 740     REFIT_VOLUME            *Volume;
 741     UINTN                   VolumeIndex;
 742
 743     for (VolumeIndex = 0; VolumeIndex < VolumesCount; VolumeIndex++) {
 744         Volume = Volumes[VolumeIndex];
 745
 746         if (Volume->RootDir != NULL) {
 747             refit_call1_wrapper(Volume->RootDir->Close, Volume->RootDir);
 748             Volume->RootDir = NULL;
 749         }
 750
 751         Volume->DeviceHandle = NULL;
 752         Volume->BlockIO = NULL;
 753         Volume->WholeDiskBlockIO = NULL;
 754     }
 755 }
 756
 757 VOID ReinitVolumes(VOID)
 758 {
 759     EFI_STATUS              Status;
 760     REFIT_VOLUME            *Volume;
 761     UINTN                   VolumeIndex;
 762     EFI_DEVICE_PATH         *RemainingDevicePath;
 763     EFI_HANDLE              DeviceHandle, WholeDiskHandle;
 764
 765     for (VolumeIndex = 0; VolumeIndex < VolumesCount; VolumeIndex++) {
 766         Volume = Volumes[VolumeIndex];
 767
 768         if (Volume->DevicePath != NULL) {
 769             // get the handle for that path
 770             RemainingDevicePath = Volume->DevicePath;
 771             Status = refit_call3_wrapper(BS->LocateDevicePath, &BlockIoProtocol, &RemainingDevicePath, &DeviceHandle);
 772
 773             if (!EFI_ERROR(Status)) {
 774                 Volume->DeviceHandle = DeviceHandle;
 775
 776                 // get the root directory
 777                 Volume->RootDir = LibOpenRoot(Volume->DeviceHandle);
 778
 779             } else
 780                 CheckError(Status, L"from LocateDevicePath");
 781         }
 782
 783         if (Volume->WholeDiskDevicePath != NULL) {
 784             // get the handle for that path
 785             RemainingDevicePath = Volume->WholeDiskDevicePath;
 786             Status = refit_call3_wrapper(BS->LocateDevicePath, &BlockIoProtocol, &RemainingDevicePath, &WholeDiskHandle);
 787
 788             if (!EFI_ERROR(Status)) {
 789                 // get the BlockIO protocol
 790                 Status = refit_call3_wrapper(BS->HandleProtocol, WholeDiskHandle, &BlockIoProtocol, (VOID **) &Volume->WholeDiskBlockIO);
 791                 if (EFI_ERROR(Status)) {
 792                     Volume->WholeDiskBlockIO = NULL;
 793                     CheckError(Status, L"from HandleProtocol");
 794                 }
 795             } else
 796                 CheckError(Status, L"from LocateDevicePath");
 797         }
 798     }
 799 }
 800
 801 //
 802 // file and dir functions
 803 //
 804
 805 BOOLEAN FileExists(IN EFI_FILE *BaseDir, IN CHAR16 *RelativePath)
 806 {
 807     EFI_STATUS         Status;
 808     EFI_FILE_HANDLE    TestFile;
 809
 810     Status = refit_call5_wrapper(BaseDir->Open, BaseDir, &TestFile, RelativePath, EFI_FILE_MODE_READ, 0);
 811     if (Status == EFI_SUCCESS) {
 812         refit_call1_wrapper(TestFile->Close, TestFile);
 813         return TRUE;
 814     }
 815     return FALSE;
 816 }
 817
 818 EFI_STATUS DirNextEntry(IN EFI_FILE *Directory, IN OUT EFI_FILE_INFO **DirEntry, IN UINTN FilterMode)
 819 {
 820     EFI_STATUS Status;
 821     VOID *Buffer;
 822     UINTN LastBufferSize, BufferSize;
 823     INTN IterCount;
 824
 825     for (;;) {
 826
 827         // free pointer from last call
 828         if (*DirEntry != NULL) {
 829             FreePool(*DirEntry);
 830             *DirEntry = NULL;
 831         }
 832
 833         // read next directory entry
 834         LastBufferSize = BufferSize = 256;
 835         Buffer = AllocatePool(BufferSize);
 836         for (IterCount = 0; ; IterCount++) {
 837             Status = refit_call3_wrapper(Directory->Read, Directory, &BufferSize, Buffer);
 838             if (Status != EFI_BUFFER_TOO_SMALL || IterCount >= 4)
 839                 break;
 840             if (BufferSize <= LastBufferSize) {
 841                 Print(L"FS Driver requests bad buffer size %d (was %d), using %d instead\n", BufferSize, LastBufferSize, LastBufferSize * 2);
 842                 BufferSize = LastBufferSize * 2;
 843 #if REFIT_DEBUG > 0
 844             } else {
 845                 Print(L"Reallocating buffer from %d to %d\n", LastBufferSize, BufferSize);
 846 #endif
 847             }
 848             Buffer = ReallocatePool(Buffer, LastBufferSize, BufferSize);
 849             LastBufferSize = BufferSize;
 850         }
 851         if (EFI_ERROR(Status)) {
 852             FreePool(Buffer);
 853             break;
 854         }
 855
 856         // check for end of listing
 857         if (BufferSize == 0) {    // end of directory listing
 858             FreePool(Buffer);
 859             break;
 860         }
 861
 862         // entry is ready to be returned
 863         *DirEntry = (EFI_FILE_INFO *)Buffer;
 864
 865         // filter results
 866         if (FilterMode == 1) {   // only return directories
 867             if (((*DirEntry)->Attribute & EFI_FILE_DIRECTORY))
 868                 break;
 869         } else if (FilterMode == 2) {   // only return files
 870             if (((*DirEntry)->Attribute & EFI_FILE_DIRECTORY) == 0)
 871                 break;
 872         } else                   // no filter or unknown filter -> return everything
 873             break;
 874
 875     }
 876     return Status;
 877 }
 878
 879 VOID DirIterOpen(IN EFI_FILE *BaseDir, IN CHAR16 *RelativePath OPTIONAL, OUT REFIT_DIR_ITER *DirIter)
 880 {
 881     if (RelativePath == NULL) {
 882         DirIter->LastStatus = EFI_SUCCESS;
 883         DirIter->DirHandle = BaseDir;
 884         DirIter->CloseDirHandle = FALSE;
 885     } else {
 886         DirIter->LastStatus = refit_call5_wrapper(BaseDir->Open, BaseDir, &(DirIter->DirHandle), RelativePath, EFI_FILE_MODE_READ, 0);
 887         DirIter->CloseDirHandle = EFI_ERROR(DirIter->LastStatus) ? FALSE : TRUE;
 888     }
 889     DirIter->LastFileInfo = NULL;
 890 }
 891
 892 BOOLEAN DirIterNext(IN OUT REFIT_DIR_ITER *DirIter, IN UINTN FilterMode, IN CHAR16 *FilePattern OPTIONAL,
 893                     OUT EFI_FILE_INFO **DirEntry)
 894 {
 895     if (DirIter->LastFileInfo != NULL) {
 896         FreePool(DirIter->LastFileInfo);
 897         DirIter->LastFileInfo = NULL;
 898     }
 899
 900     if (EFI_ERROR(DirIter->LastStatus))
 901         return FALSE;   // stop iteration
 902
 903     for (;;) {
 904         DirIter->LastStatus = DirNextEntry(DirIter->DirHandle, &(DirIter->LastFileInfo), FilterMode);
 905         if (EFI_ERROR(DirIter->LastStatus))
 906             return FALSE;
 907         if (DirIter->LastFileInfo == NULL)  // end of listing
 908             return FALSE;
 909         if (FilePattern != NULL) {
 910             if ((DirIter->LastFileInfo->Attribute & EFI_FILE_DIRECTORY))
 911                 break;
 912             if (MetaiMatch(DirIter->LastFileInfo->FileName, FilePattern))
 913                 break;
 914             // else continue loop
 915         } else
 916             break;
 917     }
 918
 919     *DirEntry = DirIter->LastFileInfo;
 920     return TRUE;
 921 }
 922
 923 EFI_STATUS DirIterClose(IN OUT REFIT_DIR_ITER *DirIter)
 924 {
 925     if (DirIter->LastFileInfo != NULL) {
 926         FreePool(DirIter->LastFileInfo);
 927         DirIter->LastFileInfo = NULL;
 928     }
 929     if (DirIter->CloseDirHandle)
 930         refit_call1_wrapper(DirIter->DirHandle->Close, DirIter->DirHandle);
 931     return DirIter->LastStatus;
 932 }
 933
 934 //
 935 // file name manipulation
 936 //
 937
 938 // Returns the filename portion (minus path name) of the
 939 // specified file
 940 CHAR16 * Basename(IN CHAR16 *Path)
 941 {
 942     CHAR16  *FileName;
 943     UINTN   i;
 944
 945     FileName = Path;
 946
 947     if (Path != NULL) {
 948         for (i = StrLen(Path); i > 0; i--) {
 949             if (Path[i-1] == '\\' || Path[i-1] == '/') {
 950                 FileName = Path + i;
 951                 break;
 952             }
 953         }
 954     }
 955
 956     return FileName;
 957 }
 958
 959 VOID ReplaceExtension(IN OUT CHAR16 *Path, IN CHAR16 *Extension)
 960 {
 961     UINTN i;
 962
 963     for (i = StrLen(Path); i >= 0; i--) {
 964         if (Path[i] == '.') {
 965             Path[i] = 0;
 966             break;
 967         }
 968         if (Path[i] == '\\' || Path[i] == '/')
 969             break;
 970     }
 971     StrCat(Path, Extension);
 972 }
 973
 974 //
 975 // memory string search
 976 //
 977
 978 INTN FindMem(IN VOID *Buffer, IN UINTN BufferLength, IN VOID *SearchString, IN UINTN SearchStringLength)
 979 {
 980     UINT8 *BufferPtr;
 981     UINTN Offset;
 982
 983     BufferPtr = Buffer;
 984     BufferLength -= SearchStringLength;
 985     for (Offset = 0; Offset < BufferLength; Offset++, BufferPtr++) {
 986         if (CompareMem(BufferPtr, SearchString, SearchStringLength) == 0)
 987             return (INTN)Offset;
 988     }
 989
 990     return -1;
 991 }
 992
 993 // Performs a case-insensitive search of BigStr for SmallStr.
 994 // Returns TRUE if found, FALSE if not.
 995 BOOLEAN StriSubCmp(IN CHAR16 *SmallStr, IN CHAR16 *BigStr) {
 996    CHAR16 *SmallCopy, *BigCopy;
 997    BOOLEAN Found = FALSE;
 998    UINTN StartPoint = 0, NumCompares = 0, SmallLen = 0;
 999
1000    if ((SmallStr != NULL) && (BigStr != NULL) && (StrLen(BigStr) >= StrLen(SmallStr))) {
1001       SmallCopy = StrDuplicate(SmallStr);
1002       BigCopy = StrDuplicate(BigStr);
1003       StrLwr(SmallCopy);
1004       StrLwr(BigCopy);
1005       SmallLen = StrLen(SmallCopy);
1006       NumCompares = StrLen(BigCopy) - SmallLen + 1;
1007       while ((!Found) && (StartPoint < NumCompares)) {
1008          Found = (StrnCmp(SmallCopy, &BigCopy[StartPoint++], SmallLen) == 0);
1009       } // while
1010       FreePool(SmallCopy);
1011       FreePool(BigCopy);
1012    } // if
1013
1014    return (Found);
1015 } // BOOLEAN StriSubCmp()
1016
1017 // Merges two strings, creating a new one and returning a pointer to it.
1018 // If AddChar != 0, the specified character is placed between the two original
1019 // strings (unless the first string is NULL). The original input string
1020 // *First is de-allocated and replaced by the new merged string.
1021 // This is similar to StrCat, but safer and more flexible because
1022 // MergeStrings allocates memory that's the correct size for the
1023 // new merged string, so it can take a NULL *First and it cleans
1024 // up the old memory. It should *NOT* be used with a constant
1025 // *First, though....
1026 VOID MergeStrings(IN OUT CHAR16 **First, IN CHAR16 *Second, CHAR16 AddChar) {
1027    UINTN Length1 = 0, Length2 = 0;
1028    CHAR16* NewString;
1029
1030    if (*First != NULL)
1031       Length1 = StrLen(*First);
1032    if (Second != NULL)
1033       Length2 = StrLen(Second);
1034    NewString = AllocatePool(sizeof(CHAR16) * (Length1 + Length2 + 2));
1035    NewString[0] = 0;
1036    if (NewString != NULL) {
1037       if (*First != NULL) {
1038          StrCat(NewString, *First);
1039          if (AddChar) {
1040             NewString[Length1] = AddChar;
1041             NewString[Length1 + 1] = 0;
1042          } // if (AddChar)
1043       } // if (First != NULL)
1044       if (First != NULL)
1045          StrCat(NewString, Second);
1046       FreePool(*First);
1047       *First = NewString;
1048    } else {
1049       Print(L"Error! Unable to allocate memory in MergeStrings()!\n");
1050    } // if/else
1051 } // static CHAR16* MergeStrings()
1052
1053 // Takes an input pathname (*Path) and locates the final directory component
1054 // of that name. For instance, if the input path is 'EFI\foo\bar.efi', this
1055 // function returns the string 'foo'.
1056 // Assumes the pathname is separated with backslashes.
1057 CHAR16 *FindLastDirName(IN CHAR16 *Path) {
1058    UINTN i, StartOfElement = 0, EndOfElement = 0, PathLength, CopyLength;
1059    CHAR16 *Found = NULL;
1060
1061    PathLength = StrLen(Path);
1062    // Find start & end of target element
1063    for (i = 0; i < PathLength; i++) {
1064       if (Path[i] == '\\') {
1065          StartOfElement = EndOfElement;
1066          EndOfElement = i;
1067       } // if
1068    } // for
1069    // Extract the target element
1070    if (EndOfElement > 0) {
1071       while ((StartOfElement < PathLength) && (Path[StartOfElement] == '\\')) {
1072          StartOfElement++;
1073       } // while
1074       EndOfElement--;
1075       if (EndOfElement >= StartOfElement) {
1076          CopyLength = EndOfElement - StartOfElement + 1;
1077          Found = StrDuplicate(&Path[StartOfElement]);
1078          if (Found != NULL)
1079             Found[CopyLength] = 0;
1080       } // if (EndOfElement >= StartOfElement)
1081    } // if (EndOfElement > 0)
1082    return (Found);
1083 } // CHAR16 *FindLastDirName
1084
1085 // Returns the directory portion of a pathname. For instance,
1086 // if FullPath is 'EFI\foo\bar.efi', this function returns the
1087 // string 'EFI\foo'.
1088 CHAR16 *FindPath(IN CHAR16* FullPath) {
1089    UINTN i, LastBackslash = 0;
1090    CHAR16 *PathOnly;
1091
1092    for (i = 0; i < StrLen(FullPath); i++) {
1093       if (FullPath[i] == '\\')
1094          LastBackslash = i;
1095    } // for
1096    PathOnly = StrDuplicate(FullPath);
1097    PathOnly[LastBackslash] = 0;
1098    return (PathOnly);
1099 }
1100
1101 // Returns all the digits in the input string, including intervening
1102 // non-digit characters. For instance, if InString is "foo-3.3.4-7.img",
1103 // this function returns "3.3.4-7". If InString contains no digits,
1104 // the return value is NULL.
1105 CHAR16 *FindNumbers(IN CHAR16 *InString) {
1106    UINTN i, StartOfElement, EndOfElement = 0, InLength, CopyLength;
1107    CHAR16 *Found = NULL;
1108
1109    InLength = StartOfElement = StrLen(InString);
1110    // Find start & end of target element
1111    for (i = 0; i < InLength; i++) {
1112       if ((InString[i] >= '0') && (InString[i] <= '9')) {
1113          if (StartOfElement > i)
1114             StartOfElement = i;
1115          if (EndOfElement < i)
1116             EndOfElement = i;
1117       } // if
1118    } // for
1119    // Extract the target element
1120    if (EndOfElement > 0) {
1121       if (EndOfElement >= StartOfElement) {
1122          CopyLength = EndOfElement - StartOfElement + 1;
1123          Found = StrDuplicate(&InString[StartOfElement]);
1124          if (Found != NULL)
1125             Found[CopyLength] = 0;
1126       } // if (EndOfElement >= StartOfElement)
1127    } // if (EndOfElement > 0)
1128    return (Found);
1129 } // CHAR16 *FindNumbers()
1130
1131 // Find the #Index element (numbered from 0) in a comma-delimited string
1132 // of elements.
1133 // Returns the found element, or NULL if Index is out of range of InString
1134 // is NULL.
1135 CHAR16 *FindCommaDelimited(IN CHAR16 *InString, IN UINTN Index) {
1136    UINTN    StartPos = 0, CurPos = 0;
1137    BOOLEAN  Found = FALSE;
1138    CHAR16   *FoundString = NULL;
1139
1140    if (InString != NULL) {
1141       // After while() loop, StartPos marks start of item #Index
1142       while ((Index > 0) && (CurPos < StrLen(InString))) {
1143          if (InString[CurPos] == L',') {
1144             Index--;
1145             StartPos = CurPos + 1;
1146          } // if
1147          CurPos++;
1148       } // while
1149       // After while() loop, CurPos is one past the end of the element
1150       while ((CurPos < StrLen(InString)) && (!Found)) {
1151          if (InString[CurPos] == L',')
1152             Found = TRUE;
1153          else
1154             CurPos++;
1155       } // while
1156    } // if
1157    if (Index == 0)
1158       FoundString = StrDuplicate(&InString[StartPos]);
1159    if (FoundString != NULL)
1160       FoundString[CurPos - StartPos] = 0;
1161    return (FoundString);
1162 } // CHAR16 *FindCommaDelimited()