low.c File Reference

#include "precomp.h"
#include <bootmbr.h>

Go to the source code of this file.

Classes
struct	_tagCHS
Defines
#define	MAX_TRANSFER   65536
#define	PSTART(p)
#define	PLENGTH(p)
#define	ZeroPartitionTableEntry(p)   SetPartitionTableEntry(p,0,SYSID_UNUSED,0,0,NULL);
#define	SECCNT(l)   ((ULONG)(((ULONGLONG)l.QuadPart)/((ULONGLONG)bps)))
Typedefs
typedef _tagCHS	CHS
typedef _tagCHS *	PCHS
Functions
ARC_STATUS	LowOpenDisk (IN PCHAR DevicePath, OUT PULONG DiskId)
ARC_STATUS	LowCloseDisk (IN ULONG DiskId)
ARC_STATUS	LowGetDriveGeometry (IN PCHAR DevicePath, OUT PULONG TotalSectorCount, OUT PULONG SectorSize, OUT PULONG SectorsPerTrack, OUT PULONG Heads)
ARC_STATUS	LowGetPartitionGeometry (IN PCHAR PartitionPath, OUT PULONG TotalSectorCount, OUT PULONG SectorSize, OUT PULONG SectorsPerTrack, OUT PULONG Heads)
ARC_STATUS	LowReadSectors (IN ULONG VolumeId, IN ULONG SectorSize, IN ULONG StartingSector, IN ULONG NumberOfSectors, OUT PVOID Buffer)
ARC_STATUS	LowWriteSectors (IN ULONG VolumeId, IN ULONG SectorSize, IN ULONG StartingSector, IN ULONG NumberOfSectors, IN PVOID Buffer)
PCHAR	AlGetPathnameFromComponent (IN PCONFIGURATION_COMPONENT Component)
ARC_STATUS	LowQueryPathFromComponent (IN PCONFIGURATION_COMPONENT Component, OUT PCHAR *Path)
ARC_STATUS	LowTraverseChildren (IN PCONFIGURATION_COMPONENT Parent, IN CONFIGURATION_CLASS *ConfigClass OPTIONAL, IN CONFIGURATION_TYPE *ConfigType OPTIONAL, IN OUT PCONFIGURATION_COMPONENT *MatchingArray OPTIONAL, IN OUT PULONG CurrentLength)
ARC_STATUS	LowQueryComponentList (IN CONFIGURATION_CLASS *ConfigClass OPTIONAL, IN CONFIGURATION_TYPE *ConfigType OPTIONAL, OUT PCONFIGURATION_COMPONENT **ComponentList, OUT PULONG ListLength)
ARC_STATUS	LowQueryPathList (IN CONFIGURATION_CLASS *ConfigClass OPTIONAL, IN CONFIGURATION_TYPE *ConfigType OPTIONAL, OUT PCHAR **PathList, OUT PULONG ListLength)
ARC_STATUS	LowFreePathList (IN PCHAR *PathList, IN ULONG ListLength)
ARC_STATUS	LowQueryFdiskPathList (OUT PCHAR **PathList, OUT PULONG ListLength)
ARC_STATUS	LowFreeFdiskPathList (IN OUT PCHAR *PathList, IN ULONG ListLength)
ARC_STATUS	LowGetDiskLayout (IN PCHAR Path, OUT PDRIVE_LAYOUT_INFORMATION *DriveLayout)
VOID	CalculateCHSVals (IN ULONG Start, IN ULONG Size, IN ULONG spt, IN ULONG h, OUT PCHS chs)
VOID	SetPartitionTableEntry (IN OUT PPARTITION_DESCRIPTOR p, IN UCHAR Active, IN UCHAR SysID, IN ULONG RelativeSector, IN ULONG SectorCount, IN PCHS chs)
VOID	ZeroPartitionTable (PPARTITION_DESCRIPTOR PartitionTable)
ARC_STATUS	LowSetDiskLayout (IN PCHAR Path, IN PDRIVE_LAYOUT_INFORMATION DriveLayout)
Variables
PCHAR	MnemonicTable []
CHAR	Pathname [256]

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Define Documentation

#define MAX_TRANSFER   65536

Definition at line 208 of file low.c. Referenced by LowReadSectors(), and LowWriteSectors().

#define PLENGTH (  p   )

Value: ( \ (ULONG) ((p)->PartitionLengthLsb0) + \ (ULONG) ((p)->PartitionLengthLsb1 << 8) + \ (ULONG) ((p)->PartitionLengthMsb0 << 16) + \ (ULONG) ((p)->PartitionLengthMsb1 << 24) ) Referenced by LowGetDiskLayout().

#define PSTART (  p   )

Value: ( \ (ULONG) ((p)->StartingSectorLsb0) + \ (ULONG) ((p)->StartingSectorLsb1 << 8) + \ (ULONG) ((p)->StartingSectorMsb0 << 16) + \ (ULONG) ((p)->StartingSectorMsb1 << 24) ) Referenced by LowGetDiskLayout().

#define SECCNT (  l   )     ((ULONG)(((ULONGLONG)l.QuadPart)/((ULONGLONG)bps)))

Referenced by LowSetDiskLayout().

#define ZeroPartitionTableEntry (  p   )     SetPartitionTableEntry(p,0,SYSID_UNUSED,0,0,NULL);

Definition at line 1060 of file low.c. Referenced by LowSetDiskLayout(), and ZeroPartitionTable().

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Typedef Documentation

typedef struct _tagCHS CHS

typedef struct _tagCHS * PCHS

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Function Documentation

PCHAR AlGetPathnameFromComponent (  IN PCONFIGURATION_COMPONENT  Component  )

Definition at line 422 of file low.c. References ArcGetParent, CHAR, MnemonicTable, NULL, Pathname, PCONFIGURATION_COMPONENT, and sprintf(). Referenced by LowQueryPathFromComponent(). 00428 : 00429 00430 This function builds an ARC pathname for the specified component. 00431 00432 Arguments: 00433 00434 Component - Supplies a pointer to a configuration component. 00435 00436 Return Value: 00437 00438 Returns a pointer to a string which contains the ARC pathname for the 00439 component. NOTE: The string is stored in static storage, and must be 00440 copied by the user before another call to this routine. 00441 00442 --*/ 00443 { 00444 PCONFIGURATION_COMPONENT ParentComponent; 00445 CHAR NewSegment[16]; 00446 CHAR Tempname[256]; 00447 00448 Pathname[0] = 0; 00449 00450 // 00451 // Loop while not at the root component. 00452 // 00453 00454 while ((ParentComponent = ArcGetParent(Component)) != NULL) { 00455 00456 // 00457 // Build new pathname segment from the Component type and key. 00458 // 00459 00460 sprintf(NewSegment, 00461 "%s(%d)", 00462 MnemonicTable[Component->Type], 00463 Component->Key); 00464 00465 // 00466 // Add the new segment as a prefix of the current pathname. 00467 // 00468 00469 strcpy(Tempname, Pathname); 00470 strcpy(Pathname, NewSegment); 00471 strcat(Pathname, Tempname); 00472 00473 // 00474 // Move to the parent component. 00475 // 00476 00477 Component = ParentComponent; 00478 } 00479 00480 return Pathname; 00481 } /******************* END OF DAVIDRO CODE *********************************/

VOID CalculateCHSVals (  IN ULONG  Start, IN ULONG  Size, IN ULONG  spt, IN ULONG  h, OUT PCHS  chs )

Definition at line 980 of file low.c. References End, Size, Start, and USHORT. Referenced by LowSetDiskLayout(). { ULONG spc = spt * h; // sectors per cylinder ULONG r; ULONG End = Start+Size-1; chs->StartCylinder = (USHORT)(Start/spc); r = Start % spc; chs->StartHead = (UCHAR)(r / spt); chs->StartSector = (UCHAR)((r % spt) + 1); // sector is 1-based chs->EndCylinder = (USHORT)(End/spc); r = End % spc; chs->EndHead = (UCHAR)(r / spt); chs->EndSector = (UCHAR)((r % spt) + 1); // sector is 1-based }

ARC_STATUS LowCloseDisk (  IN ULONG  DiskId  )

Definition at line 36 of file low.c. References ArcClose. Referenced by CheckIfDiskIsOffLine(), LowGetDiskLayout(), LowSetDiskLayout(), and ZapSector(). : This routine closes the supplied device. Arguments: DiskId - Supplies the disk id. Return Value: ArcClose --*/ { return ArcClose(DiskId); }

ARC_STATUS LowFreeFdiskPathList (  IN OUT PCHAR *  PathList, IN ULONG  ListLength )

Definition at line 786 of file low.c. References LowFreePathList(). Referenced by FdiskCleanUp(). : This routine frees up the space taken by the path lists. Arguments: PathList - Supplies the paths. ListLength - Supplies the number of paths. Return Value: ESUCCESS --*/ { return LowFreePathList(PathList, ListLength); }

ARC_STATUS LowFreePathList (  IN PCHAR *  PathList, IN ULONG  ListLength )

Definition at line 721 of file low.c. References ESUCCESS, and FreeMemory. Referenced by FmtFreeFatPartitionList(), FmtQueryFatPartitionList(), LowFreeFdiskPathList(), and LowQueryPathList(). : This routine frees up the space taken by the path lists. Arguments: PathList - Supplies the paths. ListLength - Supplies the number of paths. Return Value: ESUCCESS --*/ { ULONG i; for (i = 0; i < ListLength; i++) { if (PathList[i]) { FreeMemory(PathList[i]); } } FreeMemory(PathList); return ESUCCESS; }

ARC_STATUS LowGetDiskLayout (  IN PCHAR  Path, OUT PDRIVE_LAYOUT_INFORMATION *  DriveLayout )

Definition at line 812 of file low.c. References _PARTITION_DESCRIPTOR::ActiveFlag, AlAllocateHeap(), AlDeallocateHeap(), AlReallocateHeap(), ARC_STATUS, BOOT_RECORD_SIGNATURE, BOOT_SIGNATURE_OFFSET, dummy(), ENOMEM, ESUCCESS, FALSE, Handle, LowCloseDisk(), LowGetDriveGeometry(), LowOpenDisk(), LowReadSectors(), NULL, NUM_PARTITION_TABLE_ENTRIES, PARTITION_TABLE_OFFSET, _PARTITION_DESCRIPTOR::PartitionType, PLENGTH, PSTART, PUSHORT, SYSID_EXTENDED, SYSID_UNUSED, and TRUE. Referenced by InitializePartitionLists(). { ARC_STATUS status; ULONG Handle; ULONG i,ExtendedStart,BootSector,Entry; ULONG dummy,bps; BOOLEAN Link,mbr; PDRIVE_LAYOUT_INFORMATION DriveInfo; PPARTITION_INFORMATION p; PCHAR SectorBuffer; PPARTITION_DESCRIPTOR ptable; #define PSTART(p) ( \ (ULONG) ((p)->StartingSectorLsb0) + \ (ULONG) ((p)->StartingSectorLsb1 << 8) + \ (ULONG) ((p)->StartingSectorMsb0 << 16) + \ (ULONG) ((p)->StartingSectorMsb1 << 24) ) #define PLENGTH(p) ( \ (ULONG) ((p)->PartitionLengthLsb0) + \ (ULONG) ((p)->PartitionLengthLsb1 << 8) + \ (ULONG) ((p)->PartitionLengthMsb0 << 16) + \ (ULONG) ((p)->PartitionLengthMsb1 << 24) ) if((DriveInfo = AlAllocateHeap(sizeof(DRIVE_LAYOUT_INFORMATION) + (500*sizeof(PARTITION_INFORMATION)))) == NULL) { return(ENOMEM); } p = &DriveInfo->PartitionEntry[0]; if((status = LowGetDriveGeometry(Path,&dummy,&bps,&dummy,&dummy)) != ESUCCESS) { AlDeallocateHeap(DriveInfo); return(status); } if((SectorBuffer = AlAllocateHeap(bps)) == NULL) { AlDeallocateHeap(DriveInfo); return(ENOMEM); } ptable = (PPARTITION_DESCRIPTOR)(SectorBuffer + (2*PARTITION_TABLE_OFFSET)); if((status = LowOpenDisk(Path,&Handle)) != ESUCCESS) { AlDeallocateHeap(SectorBuffer); AlDeallocateHeap(DriveInfo); return(status); } mbr = TRUE; Entry = 0; BootSector = 0; ExtendedStart = 0; status = ESUCCESS; do { if((status = LowReadSectors(Handle,bps,BootSector,1,SectorBuffer)) != ESUCCESS) { break; } // This is to catch the case where there is no MBR yet. if(((PUSHORT)SectorBuffer)[BOOT_SIGNATURE_OFFSET] != BOOT_RECORD_SIGNATURE) { break; } Link = FALSE; for(i=0; i<NUM_PARTITION_TABLE_ENTRIES; i++) { if(ptable[i].PartitionType == SYSID_UNUSED) { // set as unused. p[Entry].PartitionType = SYSID_UNUSED; p[Entry].BootIndicator = FALSE; p[Entry].RewritePartition = FALSE; p[Entry].PartitionLength.QuadPart = 0; p[Entry].HiddenSectors = 0; p[Entry].StartingOffset.QuadPart = 0; p[Entry].RecognizedPartition = FALSE; } else { LARGE_INTEGER Result1, Result2; p[Entry].PartitionType = ptable[i].PartitionType; p[Entry].BootIndicator = ptable[i].ActiveFlag; p[Entry].RewritePartition = FALSE; p[Entry].PartitionLength.QuadPart = UInt32x32To64(PLENGTH(ptable + i),bps); // BUGBUG (tedm) the following are not correct for link // entries in the extended partition. // But fdisk does not use these values in // this case so blow it off. As of // 11/13/91, IoReadPartitionTable has the // same bug. p[Entry].HiddenSectors = PSTART(ptable + i); Result1.QuadPart = UInt32x32To64(PSTART(ptable + i),bps); Result2.QuadPart = UInt32x32To64(BootSector,bps); p[Entry].StartingOffset.QuadPart = Result1.QuadPart + Result2.QuadPart; p[Entry].RecognizedPartition = TRUE; // BUGBUG this is broken if(p[Entry].PartitionType == SYSID_EXTENDED) { Link = TRUE; if(mbr) { mbr = FALSE; BootSector = PSTART(ptable + i); ExtendedStart = BootSector; } else { BootSector = ExtendedStart + PSTART(ptable + i); } } } Entry++; } } while(Link); LowCloseDisk(Handle); AlDeallocateHeap(SectorBuffer); if(status != ESUCCESS) { AlDeallocateHeap(DriveInfo); return(status); } // reallocate DriveInfo, set PartitionCount field. // DriveInfo is shrinking. DriveInfo = AlReallocateHeap(DriveInfo, sizeof(DRIVE_LAYOUT_INFORMATION) + ((Entry - 1) * sizeof(PARTITION_INFORMATION)) ); DriveInfo->PartitionCount = Entry; *DriveLayout = DriveInfo; return(ESUCCESS); }

ARC_STATUS LowGetDriveGeometry (  IN PCHAR  DevicePath, OUT PULONG  TotalSectorCount, OUT PULONG  SectorSize, OUT PULONG  SectorsPerTrack, OUT PULONG  Heads )

Definition at line 59 of file low.c. References Buffer, LowGetPartitionGeometry(), SectorSize, and sprintf(). Referenced by GetGeometry(), LowGetDiskLayout(), and LowSetDiskLayout(). { char Buffer[256]; sprintf(Buffer,"%spartition(0)",DevicePath); return(LowGetPartitionGeometry(Buffer,TotalSectorCount,SectorSize,SectorsPerTrack,Heads)); }

ARC_STATUS LowGetPartitionGeometry (  IN PCHAR  PartitionPath, OUT PULONG  TotalSectorCount, OUT PULONG  SectorSize, OUT PULONG  SectorsPerTrack, OUT PULONG  Heads )

Definition at line 76 of file low.c. References ARC_STATUS, ArcClose, ArcGetComponent, ArcGetConfigurationData, ArcGetFileInformation, ArcOpen, ArcOpenReadOnly, CHAR, _CONFIGURATION_COMPONENT::ConfigurationDataLength, E2BIG, EINVAL, _FILE_INFORMATION::EndingAddress, ESUCCESS, FILE_INFORMATION, NULL, SectorSize, and _FILE_INFORMATION::StartingAddress. Referenced by FmtFatFormat(), FmtIsFat(), and LowGetDriveGeometry(). : This routine computes the drive geometry for the given partition or physical disk. Arguments: PartitionPath - Supplies a path to the partition or physical disk. NumberOfSectors - Returns the number of sectors. SectorSize - Returns the sector size. SectorsPerTrack - Returns the number of sectors per track. Heads - Returns the number of heads. Return Value: ArcOpen, ArcGetFileInformation, ArcClose, E2BIG, ESUCCESS --*/ { FILE_INFORMATION file_info; ARC_STATUS r; ULONG fileid; LARGE_INTEGER l; CM_DISK_GEOMETRY_DEVICE_DATA *DiskGeometry; CONFIGURATION_COMPONENT *DiskComponent; CM_PARTIAL_RESOURCE_LIST *DiskConfiguration; CHAR DataBuffer[sizeof(CM_PARTIAL_RESOURCE_LIST) + sizeof(CM_DISK_GEOMETRY_DEVICE_DATA)]; CM_PARTIAL_RESOURCE_DESCRIPTOR *DiskData; // Always assume 512 bytes per sector. *SectorSize = 512; // Assume the SCSI default values for number of heads and sectors per track *SectorsPerTrack = 32; *Heads = 64; // See if there is device specific data describing the geometry of // the drive. If there is none, then just use the default SCSI // values. DiskComponent = ArcGetComponent(PartitionPath); if (DiskComponent == NULL) { return EINVAL; } // // See if the ConfigurationDataLength is correct // It should contain one DeviceSpecific resource descriptor // if (DiskComponent->ConfigurationDataLength == sizeof(CM_PARTIAL_RESOURCE_LIST) + sizeof(CM_DISK_GEOMETRY_DEVICE_DATA) ) { DiskConfiguration = (CM_PARTIAL_RESOURCE_LIST *)DataBuffer; r = ArcGetConfigurationData(DiskConfiguration,DiskComponent); if (r == ESUCCESS) { // // See if the Configuration Data has ARC version 1.3 or greater // if ( (DiskConfiguration->Version == 1 && DiskConfiguration->Revision >=3 ) || (DiskConfiguration->Version > 1) ) { DiskData = &(DiskConfiguration->PartialDescriptors[DiskConfiguration->Count-1]); if (DiskData->Type == CmResourceTypeDeviceSpecific) { if (DiskData->u.DeviceSpecificData.DataSize == sizeof(CM_DISK_GEOMETRY_DEVICE_DATA)) { DiskGeometry = (CM_DISK_GEOMETRY_DEVICE_DATA *) &(DiskConfiguration->PartialDescriptors[DiskConfiguration->Count]); *SectorsPerTrack = DiskGeometry->SectorsPerTrack; *Heads = DiskGeometry->NumberOfHeads; *SectorSize = DiskGeometry->BytesPerSector; } } } } } // PrintError("SectorSize = %08x",*SectorSize); // PrintError("SectorsPerTrack = %08x",*SectorsPerTrack); // PrintError("Heads = %08x",*Heads); r = ArcOpen(PartitionPath, ArcOpenReadOnly, &fileid); if (r != ESUCCESS) { return r; } r = ArcGetFileInformation(fileid, &file_info); if (r != ESUCCESS) { return r; } r = ArcClose(fileid); if (r != ESUCCESS) { return r; } l.QuadPart = file_info.EndingAddress.QuadPart - file_info.StartingAddress.QuadPart; l.QuadPart = ((ULONGLONG)l.QuadPart) / ((ULONGLONG)(*SectorSize)); if (l.HighPart) { return E2BIG; } *TotalSectorCount = l.LowPart; return ESUCCESS; }

ARC_STATUS LowOpenDisk (  IN PCHAR  DevicePath, OUT PULONG  DiskId )

Definition at line 6 of file low.c. References ArcOpen, ArcOpenReadWrite, and sprintf(). Referenced by CheckIfDiskIsOffLine(), LowGetDiskLayout(), LowSetDiskLayout(), and ZapSector(). : This routine opens the supplied device for DASD access. Arguments: DevicePath - Supplies the device path to be opened. DiskId - Returns the disk id. Return Value: ArcOpen --*/ { char buffer[256]; sprintf(buffer,"%spartition(0)",DevicePath); return ArcOpen(buffer, ArcOpenReadWrite, DiskId); }

ARC_STATUS LowQueryComponentList (  IN CONFIGURATION_CLASS *ConfigClass  OPTIONAL, IN CONFIGURATION_TYPE *ConfigType  OPTIONAL, OUT PCONFIGURATION_COMPONENT **  ComponentList, OUT PULONG  ListLength )

Definition at line 595 of file low.c. References AllocateMemory, ARC_STATUS, ENOMEM, ESUCCESS, LowTraverseChildren(), and NULL. Referenced by LowQueryPathList(). : This routine returns an array of components whose class and type match the ones given. (Since each parameter is optional, you can do type-only and class-only searches.) The array is allocated on the heap and contains pointers to the actual components (NOT copies). Arguments: ConfigClass - Supplies the configuation class to search for. ConfigType - Supplies the configuration type to search for. ComponentList - Returns a list of pointers to components whose class and type match 'ConfigClass' and 'ConfigType'. ListLength - Returns the number of components in the list. Return Value: LowTraverseChildren, ENOMEM --*/ { ARC_STATUS r; *ListLength = 0; r = LowTraverseChildren(NULL, ConfigClass, ConfigType, NULL, ListLength); if (r != ESUCCESS) { return r; } if (!(*ComponentList = (PCONFIGURATION_COMPONENT*) AllocateMemory( (*ListLength)*sizeof(PCONFIGURATION_COMPONENT)))) { return ENOMEM; } *ListLength = 0; return LowTraverseChildren(NULL, ConfigClass, ConfigType, *ComponentList, ListLength); }

ARC_STATUS LowQueryFdiskPathList (  OUT PCHAR **  PathList, OUT PULONG  ListLength )

Definition at line 756 of file low.c. References CONFIGURATION_TYPE, DiskPeripheral, LowQueryPathList(), and NULL. Referenced by FdiskInitialize(). : This routine returns a list of paths to all the devices of interest to FDISK. Arguments: PathList - Returns a list of paths. ListLength - Returns the length of the list. Return Value: LowQueryComponentList, LowQueryPathFromComponent, ESUCCESS --*/ { CONFIGURATION_TYPE config_type; config_type = DiskPeripheral; return LowQueryPathList(NULL, &config_type, PathList, ListLength); }

ARC_STATUS LowQueryPathFromComponent (  IN PCONFIGURATION_COMPONENT  Component, OUT PCHAR *  Path )

Definition at line 486 of file low.c. References AlGetPathnameFromComponent(), AllocateMemory, ENOMEM, ESUCCESS, path, and strlen(). Referenced by LowQueryPathList(). : This routine computes a path from a component. The resulting path is allocated on the heap. Arguments: Component - Supplies a component. Path - Returns the path corresponding to that component. Return Value: ENOMEM, ESUCCESS --*/ { PCHAR p; PCHAR path; p = AlGetPathnameFromComponent(Component); path = AllocateMemory(strlen(p) + 1); if (!path) { return ENOMEM; } strcpy(path, p); *Path = path; return ESUCCESS; }

ARC_STATUS LowQueryPathList (  IN CONFIGURATION_CLASS *ConfigClass  OPTIONAL, IN CONFIGURATION_TYPE *ConfigType  OPTIONAL, OUT PCHAR **  PathList, OUT PULONG  ListLength )

Definition at line 651 of file low.c. References AllocateMemory, ARC_STATUS, ENOMEM, ESUCCESS, FreeMemory, LowFreePathList(), LowQueryComponentList(), LowQueryPathFromComponent(), and NULL. Referenced by FmtQueryFatPartitionList(), and LowQueryFdiskPathList(). : This routine returns a list of paths to the components that are of class ConfigClass and of type ConfigType. Arguments: ConfigClass - Supplies the configuation class to search for. ConfigType - Supplies the configuration type to search for. PathList - Returns a list of paths to the components. ListLength - Returns the number of components in the list. Return Value: LowQueryComponentList, LowQueryPathFromComponent --*/ { PCONFIGURATION_COMPONENT* component_list; ULONG list_length; ARC_STATUS r; ULONG i; PCHAR* path_list; r = LowQueryComponentList(ConfigClass, ConfigType, &component_list, &list_length); if (r != ESUCCESS) { return r; } if (!(path_list = (PCHAR*) AllocateMemory(list_length*sizeof(PCHAR)))) { FreeMemory(component_list); return ENOMEM; } for (i = 0; i < list_length; i++) { path_list[i] = NULL; } for (i = 0; i < list_length; i++) { r = LowQueryPathFromComponent(component_list[i], &path_list[i]); if (r != ESUCCESS) { FreeMemory(component_list); LowFreePathList(path_list, list_length); return r; } } FreeMemory(component_list); *PathList = path_list; *ListLength = list_length; return ESUCCESS; }

ARC_STATUS LowReadSectors (  IN ULONG  VolumeId, IN ULONG  SectorSize, IN ULONG  StartingSector, IN ULONG  NumberOfSectors, OUT PVOID  Buffer )

Definition at line 212 of file low.c. References ARC_STATUS, ArcRead, ArcSeek, Buffer, c, EIO, ESUCCESS, MAX_TRANSFER, min, SectorSize, and SeekAbsolute. Referenced by FmtIsFatPartition(), FmtVerifySectors(), and LowGetDiskLayout(). : This routine reads 'NumberOfSectors' sectors starting at sector 'StartingSector' on the volume with ID 'VolumeId'. Arguments: VolumeId - Supplies the ID for the volume. SectorSize - Supplies the number of bytes per sector. StartingSector - Supplies the starting sector for the read. NumberOfSectors - Supplies the number of sectors to read. Buffer - Returns the read in sectors. Return Value: ArcSeek, ArcRead, EIO, ESUCCESS --*/ { ARC_STATUS r; ULONG c; LARGE_INTEGER l; ULONG i; ULONG transfer; PCHAR buf; ULONG total; l.QuadPart = UInt32x32To64(StartingSector,SectorSize); buf = (PCHAR) Buffer; r = ArcSeek(VolumeId, &l, SeekAbsolute); if (r != ESUCCESS) { return r; } total = SectorSize*NumberOfSectors; for (i = 0; i < total; i += MAX_TRANSFER) { transfer = min(MAX_TRANSFER, total - i); r = ArcRead(VolumeId, &buf[i], transfer, &c); if (r != ESUCCESS) { return r; } if (c != transfer) { return EIO; } } return ESUCCESS; }

ARC_STATUS LowSetDiskLayout (  IN PCHAR  Path, IN PDRIVE_LAYOUT_INFORMATION  DriveLayout )

Definition at line 1076 of file low.c. References AlAllocateHeap(), AlDeallocateHeap(), ARC_STATUS, ASRT, BOOT_RECORD_SIGNATURE, BOOT_SIGNATURE_OFFSET, CalculateCHSVals(), dummy(), ENOMEM, ENTRIES_PER_BOOTSECTOR, ESUCCESS, FALSE, Handle, LowCloseDisk(), LowGetDriveGeometry(), LowOpenDisk(), LowWriteSectors(), min, NULL, PARTITION_TABLE_OFFSET, _PARTITION_DESCRIPTOR::PartitionType, PUSHORT, SECCNT, SetPartitionTableEntry(), SYSID_EXTENDED, SYSID_UNUSED, TRUE, ZeroPartitionTable(), and ZeroPartitionTableEntry. Referenced by WriteDriveLayout(). { ARC_STATUS status; ULONG dummy,bps,spt,h; PCHAR SectorBuffer; ULONG Handle; PPARTITION_DESCRIPTOR PartitionTable; PPARTITION_INFORMATION p; BOOLEAN mbr = TRUE,Update; ULONG BootSector = 0,ExtendedPartitionStart = 0, NextBootSector; ULONG i,j,UsedCount; CHS chs; #define SECCNT(l) ((ULONG)(((ULONGLONG)l.QuadPart)/((ULONGLONG)bps))) ASRT(DriveLayout->PartitionCount); if((status = LowGetDriveGeometry(Path,&dummy,&bps,&spt,&h)) != ESUCCESS) { return(status); } // allocate a buffer for sector I/O if((SectorBuffer = AlAllocateHeap(bps)) == NULL) { return(ENOMEM); } // // Use x86 bootcode as a template so the disk will boot an x86 // if it is moved to disk0 on an x86 machine. // RtlMoveMemory(SectorBuffer,x86BootCode,min(X86BOOTCODE_SIZE,bps)); ((PUSHORT)SectorBuffer)[BOOT_SIGNATURE_OFFSET] = BOOT_RECORD_SIGNATURE; PartitionTable = (PPARTITION_DESCRIPTOR)(&(((PUSHORT)SectorBuffer)[PARTITION_TABLE_OFFSET])); if((status = LowOpenDisk(Path,&Handle)) != ESUCCESS) { AlDeallocateHeap(SectorBuffer); return(status); } ASRT(!(DriveLayout->PartitionCount % ENTRIES_PER_BOOTSECTOR)); for(i=0; i<DriveLayout->PartitionCount; i+=ENTRIES_PER_BOOTSECTOR) { Update = FALSE; UsedCount = 0; ZeroPartitionTable(PartitionTable); for(j=0; j<ENTRIES_PER_BOOTSECTOR; j++) { p = &DriveLayout->PartitionEntry[i+j]; switch(p->PartitionType) { case SYSID_UNUSED: ZeroPartitionTableEntry(PartitionTable+j); break; case SYSID_EXTENDED: NextBootSector = SECCNT(p->StartingOffset); CalculateCHSVals(NextBootSector,SECCNT(p->PartitionLength),spt,h,&chs); SetPartitionTableEntry(PartitionTable+j, p->BootIndicator, SYSID_EXTENDED, SECCNT(p->StartingOffset) - ExtendedPartitionStart, SECCNT(p->PartitionLength), &chs ); if(mbr) { mbr = FALSE; ExtendedPartitionStart = NextBootSector; } break; default: CalculateCHSVals(SECCNT(p->StartingOffset),SECCNT(p->PartitionLength),spt,h,&chs); SetPartitionTableEntry(PartitionTable+j, p->BootIndicator, p->PartitionType, SECCNT(p->StartingOffset) - BootSector, SECCNT(p->PartitionLength), &chs ); break; } Update = Update || p->RewritePartition; if(p->PartitionType != SYSID_UNUSED) { UsedCount++; } } if(Update || !UsedCount) { if((status = LowWriteSectors(Handle,bps,BootSector,1,SectorBuffer)) != ESUCCESS) { LowCloseDisk(Handle); AlDeallocateHeap(SectorBuffer); return(status); } } BootSector = NextBootSector; } LowCloseDisk(Handle); AlDeallocateHeap(SectorBuffer); return(ESUCCESS); }

ARC_STATUS LowTraverseChildren (  IN PCONFIGURATION_COMPONENT  Parent, IN CONFIGURATION_CLASS *ConfigClass  OPTIONAL, IN CONFIGURATION_TYPE *ConfigType  OPTIONAL, IN OUT PCONFIGURATION_COMPONENT *MatchingArray  OPTIONAL, IN OUT PULONG  CurrentLength )

Definition at line 528 of file low.c. References ARC_STATUS, ArcGetChild, ArcGetPeer, _CONFIGURATION_COMPONENT::Class, CurrentLength, ESUCCESS, and _CONFIGURATION_COMPONENT::Type. Referenced by LowQueryComponentList(). : This routine traverses the trees whose parent is 'Parent'. If the Matching array is provided then it will be filled with pointers to all of the components whose type and class match 'ConfigType' and 'ConfigClass'. Also, the 'CurrentLength' is incremented by the number of nodes that match. Arguments: Parent - Supplies the root of the tree. ConfigClass - Supplies the class to search for. ConfigType - Supplies the type to search for. CurrentLength - Supplies the current count. Return Value: ESUCCESS --*/ { PCONFIGURATION_COMPONENT pc; ARC_STATUS r; if (!(pc = ArcGetChild(Parent))) { return ESUCCESS; } for (;;) { if ((!ConfigClass || pc->Class == *ConfigClass) && (!ConfigType || pc->Type == *ConfigType)) { if (MatchingArray) { MatchingArray[*CurrentLength] = pc; } (*CurrentLength)++; } r = LowTraverseChildren(pc, ConfigClass, ConfigType, MatchingArray, CurrentLength); if (r != ESUCCESS) { return r; } if (!(pc = ArcGetPeer(pc))) { break; } } return ESUCCESS; }

ARC_STATUS LowWriteSectors (  IN ULONG  VolumeId, IN ULONG  SectorSize, IN ULONG  StartingSector, IN ULONG  NumberOfSectors, IN PVOID  Buffer )

Definition at line 281 of file low.c. References ARC_STATUS, ArcSeek, ArcWrite, Buffer, c, EIO, ESUCCESS, MAX_TRANSFER, min, SectorSize, and SeekAbsolute. Referenced by FmtFatFormat(), LowSetDiskLayout(), and ZapSector(). : This routine write 'NumberOfSectors' sectors starting at sector 'StartingSector' on the volume with ID 'VolumeId'. Arguments: VolumeId - Supplies the ID for the volume. SectorSize - Supplies the number of bytes per sector. StartingSector - Supplies the starting sector for the write. NumberOfSectors - Supplies the number of sectors to write. Buffer - Supplies the sectors to write. Return Value: ArcSeek, ArcWrite, EIO, ESUCCESS --*/ { ARC_STATUS r; ULONG c; LARGE_INTEGER l; ULONG i; ULONG transfer; PCHAR buf; ULONG total; l.QuadPart = UInt32x32To64(StartingSector,SectorSize); buf = (PCHAR) Buffer; r = ArcSeek(VolumeId, &l, SeekAbsolute); if (r != ESUCCESS) { return r; } total = SectorSize*NumberOfSectors; for (i = 0; i < total; i += MAX_TRANSFER) { transfer = min(MAX_TRANSFER, total - i); r = ArcWrite(VolumeId, &buf[i], transfer, &c); if (r != ESUCCESS) { return r; } if (c != transfer) { return EIO; } } return ESUCCESS; }

VOID SetPartitionTableEntry (  IN OUT PPARTITION_DESCRIPTOR  p, IN UCHAR  Active, IN UCHAR  SysID, IN ULONG  RelativeSector, IN ULONG  SectorCount, IN PCHS  chs )

Definition at line 1005 of file low.c. References Active. Referenced by LowSetDiskLayout(). { // first get the easy ones out of the way. p->ActiveFlag = Active; p->PartitionType = SysID; if(chs) { p->StartingTrack = chs->StartHead; p->EndingTrack = chs->EndHead; } else { p->StartingTrack = 0; p->EndingTrack = 0; } if(chs) { // pack sector/cyl values p->StartingCylinderLsb = (chs->StartSector & 0x3f) | ((chs->StartCylinder >> 2) & 0xc0); p->StartingCylinderMsb = (UCHAR)chs->StartCylinder; p->EndingCylinderLsb = (chs->EndSector & 0x3f) | ((chs->EndCylinder >> 2) & 0xc0); p->EndingCylinderMsb = (UCHAR)chs->EndCylinder; } else { p->StartingCylinderLsb = 0; p->StartingCylinderMsb = 0; p->EndingCylinderLsb = 0; p->EndingCylinderMsb = 0; } // now handle the relative and total sector counts p->StartingSectorLsb0 = (UCHAR)(RelativeSector >> 0 ); p->StartingSectorLsb1 = (UCHAR)(RelativeSector >> 8 ); p->StartingSectorMsb0 = (UCHAR)(RelativeSector >> 16); p->StartingSectorMsb1 = (UCHAR)(RelativeSector >> 24); p->PartitionLengthLsb0 = (UCHAR)(SectorCount >> 0 ); p->PartitionLengthLsb1 = (UCHAR)(SectorCount >> 8 ); p->PartitionLengthMsb0 = (UCHAR)(SectorCount >> 16); p->PartitionLengthMsb1 = (UCHAR)(SectorCount >> 24); }

VOID ZeroPartitionTable (  PPARTITION_DESCRIPTOR  PartitionTable  )

Definition at line 1063 of file low.c. References ENTRIES_PER_BOOTSECTOR, and ZeroPartitionTableEntry. Referenced by LowSetDiskLayout(). { ULONG i; for(i=0; i<ENTRIES_PER_BOOTSECTOR; i++) { ZeroPartitionTableEntry(PartitionTable+i); } }

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Variable Documentation

PCHAR MnemonicTable[]

Definition at line 373 of file low.c. Referenced by AlGetPathnameFromComponent().

CHAR Pathname[256]

Definition at line 418 of file low.c. Referenced by AlGetPathnameFromComponent().

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