dictlib.c File Reference

#include <ntddk.h>
#include <classpnp.h>

Include dependency graph for dictlib.c:

Go to the source code of this file.

Classes
struct	_DICTIONARY_HEADER

Macros
#define	DICTIONARY_SIGNATURE   'tciD'

Typedefs
typedef struct _DICTIONARY_HEADER	DICTIONARY_HEADER
typedef struct _DICTIONARY_HEADER *	PDICTIONARY_HEADER

Functions
VOID	InitializeDictionary (IN PDICTIONARY Dictionary)
BOOLEAN	TestDictionarySignature (IN PDICTIONARY Dictionary)
NTSTATUS	AllocateDictionaryEntry (IN PDICTIONARY Dictionary, IN ULONGLONG Key, _In_range_(0, sizeof(FILE_OBJECT_EXTENSION)) IN ULONG Size, IN ULONG Tag, OUT PVOID *Entry)
PVOID	GetDictionaryEntry (IN PDICTIONARY Dictionary, IN ULONGLONG Key)
VOID	FreeDictionaryEntry (IN PDICTIONARY Dictionary, IN PVOID Entry)

Macro Definition Documentation

DICTIONARY_SIGNATURE

#define DICTIONARY_SIGNATURE   'tciD'

Definition at line 38 of file dictlib.c.

Typedef Documentation

DICTIONARY_HEADER

typedef struct _DICTIONARY_HEADER DICTIONARY_HEADER

Definition at line 54 of file dictlib.c.

PDICTIONARY_HEADER

typedef struct _DICTIONARY_HEADER * PDICTIONARY_HEADER

Definition at line 54 of file dictlib.c.

Function Documentation

AllocateDictionaryEntry()

NTSTATUS AllocateDictionaryEntry	(	IN PDICTIONARY	Dictionary,
		IN ULONGLONG	Key,
		_In_range_(0, sizeof(FILE_OBJECT_EXTENSION)) IN ULONG	Size,
		IN ULONG	Tag,
		OUT PVOID *	Entry
	)

Definition at line 78 of file dictlib.c.

{
    PDICTIONARY_HEADER header;
    KIRQL oldIrql;
    PDICTIONARY_HEADER *entry;
 
    NTSTATUS status = STATUS_SUCCESS;
 
    *Entry = NULL;
 
    header = ExAllocatePoolWithTag(NonPagedPoolNx,
                                   Size + sizeof(DICTIONARY_HEADER),
                                   Tag);
 
    if(header == NULL) {
        return STATUS_INSUFFICIENT_RESOURCES;
    }
 
    RtlZeroMemory(header, sizeof(DICTIONARY_HEADER) + Size);
    header->Key = Key;
 
    //
    // Find the correct location for this entry in the dictionary.
    //
 
    KeAcquireSpinLock(&(Dictionary->SpinLock), &oldIrql);
 
    TRY {
 
        entry = &(Dictionary->List);
 
        while(*entry != NULL) {
            if((*entry)->Key == Key) {
 
                //
                // Dictionary must have unique keys.
                //
 
                status = STATUS_OBJECT_NAME_COLLISION;
                LEAVE;
 
            } else if ((*entry)->Key < Key) {
 
                //
                // We will go ahead and insert the key in here.
                //
                break;
            } else {
                entry = &((*entry)->Next);
            }
        }
 
        //
        // If we make it here then we will go ahead and do the insertion.
        //
 
        header->Next = *entry;
        *entry = header;
 
    } FINALLY {
        KeReleaseSpinLock(&(Dictionary->SpinLock), oldIrql);
 
        if(!NT_SUCCESS(status)) {
            FREE_POOL(header);
        } else {
            *Entry = (PVOID) header->Data;
        }
    }
    return status;
}

FreeDictionaryEntry()

VOID FreeDictionaryEntry	(	IN PDICTIONARY	Dictionary,
		IN PVOID	Entry
	)

Definition at line 189 of file dictlib.c.

{
    PDICTIONARY_HEADER header;
    PDICTIONARY_HEADER *entry;
    KIRQL oldIrql;
    BOOLEAN found;
 
    found = FALSE;
    header = CONTAINING_RECORD(Entry, DICTIONARY_HEADER, Data);
 
    KeAcquireSpinLock(&(Dictionary->SpinLock), &oldIrql);
 
    entry = &(Dictionary->List);
    while(*entry != NULL) {
 
        if(*entry == header) {
            *entry = header->Next;
            found = TRUE;
            break;
        } else {
            entry = &(*entry)->Next;
        }
    }
 
    KeReleaseSpinLock(&(Dictionary->SpinLock), oldIrql);
 
    //
    // calling this w/an invalid pointer invalidates the dictionary system,
    // so NT_ASSERT() that we never try to Free something not in the list
    //
 
    NT_ASSERT(found);
    if (found) {
        FREE_POOL(header);
    }
 
    return;
 
}

Referenced by ClasspCreateClose().

GetDictionaryEntry()

PVOID GetDictionaryEntry	(	IN PDICTIONARY	Dictionary,
		IN ULONGLONG	Key
	)

Definition at line 157 of file dictlib.c.

{
    PDICTIONARY_HEADER entry;
    PVOID data;
    KIRQL oldIrql;
 
 
    data = NULL;
 
    KeAcquireSpinLock(&(Dictionary->SpinLock), &oldIrql);
 
    entry = Dictionary->List;
    while (entry != NULL) {
 
        if (entry->Key == Key) {
            data = entry->Data;
            break;
        } else {
            entry = entry->Next;
        }
    }
 
    KeReleaseSpinLock(&(Dictionary->SpinLock), oldIrql);
 
    return data;
}

Referenced by _IRQL_requires_max_().

InitializeDictionary()

VOID InitializeDictionary

(

IN PDICTIONARY

Dictionary

)

Definition at line 58 of file dictlib.c.

{
    RtlZeroMemory(Dictionary, sizeof(DICTIONARY));
    Dictionary->Signature = DICTIONARY_SIGNATURE;
    KeInitializeSpinLock(&Dictionary->SpinLock);
    return;
}

TestDictionarySignature()

BOOLEAN TestDictionarySignature

(

IN PDICTIONARY

Dictionary

)

Definition at line 70 of file dictlib.c.

{
    return Dictionary->Signature == DICTIONARY_SIGNATURE;
}