reactos/ntoskrnl/ke/config.c

126 lines
3.9 KiB
C

/*
* PROJECT: ReactOS Kernel
* LICENSE: GPL - See COPYING in the top level directory
* FILE: ntoskrnl/ke/config.c
* PURPOSE: Configuration Tree Routines
* PROGRAMMERS: Alex Ionescu (alex.ionescu@reactos.org)
*/
/* INCLUDES ******************************************************************/
#include <ntoskrnl.h>
#define NDEBUG
#include <debug.h>
/* FUNCTIONS *****************************************************************/
/*
* @implemented
*/
PCONFIGURATION_COMPONENT_DATA
NTAPI
KeFindConfigurationEntry(IN PCONFIGURATION_COMPONENT_DATA Child,
IN CONFIGURATION_CLASS Class,
IN CONFIGURATION_TYPE Type,
IN PULONG ComponentKey OPTIONAL)
{
PCONFIGURATION_COMPONENT_DATA NextLink = NULL;
/* Start Search at Root */
return KeFindConfigurationNextEntry(Child,
Class,
Type,
ComponentKey,
&NextLink);
}
/*
* @implemented
*/
PCONFIGURATION_COMPONENT_DATA
NTAPI
KeFindConfigurationNextEntry(IN PCONFIGURATION_COMPONENT_DATA Child,
IN CONFIGURATION_CLASS Class,
IN CONFIGURATION_TYPE Type,
IN PULONG ComponentKey OPTIONAL,
IN PCONFIGURATION_COMPONENT_DATA *NextLink)
{
ULONG Key = 0;
ULONG Mask = 0;
PCONFIGURATION_COMPONENT_DATA Sibling;
PCONFIGURATION_COMPONENT_DATA ReturnEntry;
/* If we did get a key, then use it instead */
if (ComponentKey)
{
Key = *ComponentKey;
Mask = -1;
}
/* Loop the Components until we find a a match */
while (Child)
{
/* Check if we are starting somewhere already */
if (*NextLink)
{
/* If we've found the place where we started, clear and continue */
if (Child == *NextLink) *NextLink = NULL;
}
else
{
/* Try to get a match */
if ((Child->ComponentEntry.Class) == Class &&
(Child->ComponentEntry.Type) == Type &&
(Child->ComponentEntry.Key & Mask) == Key)
{
/* Match found */
return Child;
}
}
/* Now we've also got to lookup the siblings */
Sibling = Child->Sibling;
while (Sibling)
{
/* Check if we are starting somewhere already */
if (*NextLink)
{
/* If we've found the place where we started, clear and continue */
if (Sibling == *NextLink) *NextLink = NULL;
}
else
{
/* Try to get a match */
if ((Sibling->ComponentEntry.Class == Class) &&
(Sibling->ComponentEntry.Type == Type) &&
(Sibling->ComponentEntry.Key & Mask) == Key)
{
/* Match found */
return Sibling;
}
}
/* We've got to check if the Sibling has a Child as well */
if (Sibling->Child)
{
/* We're just going to call ourselves again */
ReturnEntry = KeFindConfigurationNextEntry(Sibling->Child,
Class,
Type,
ComponentKey,
NextLink);
if (ReturnEntry) return ReturnEntry;
}
/* Next Sibling */
Sibling = Sibling->Sibling;
}
/* Next Child */
Child = Child->Child;
}
/* If we got here, nothing was found */
return NULL;
}