Function Ext2BuildName

Ext4Fsd/memory.c:1358–1425

BOOLEAN
Ext2BuildName(
    IN OUT PUNICODE_STRING  Target,
    IN PUNICODE_STRING      File,
    IN PUNICODE_STRING      Parent
)
{
    USHORT  Length = 0;
    USHORT  ParentLen = 0;
    BOOLEAN bBackslash = TRUE;

    /* free the original buffer */
    if (Target->Buffer) {
        DEC_MEM_COUNT(PS_MCB_NAME, Target->Buffer, Target->MaximumLength);
        Ext2FreePool(Target->Buffer, EXT2_FNAME_MAGIC);
        Target->Length = Target->MaximumLength = 0;
    }

    /* check the parent directory's name and backslash */
    if (Parent && Parent->Buffer && Parent->Length > 0) {
        ParentLen = Parent->Length / sizeof(WCHAR);
        if (Parent->Buffer[ParentLen - 1] == L'\\') {
            bBackslash = FALSE;
        }
    }

    if (Parent == NULL || File->Buffer[0] == L'\\') {
        /* must be root inode */
        ASSERT(ParentLen == 0);
        bBackslash = FALSE;
    }

    /* allocate and initialize new name buffer */
    Length  = File->Length;
    Length += (ParentLen + (bBackslash ? 1 : 0)) * sizeof(WCHAR);

    Target->Buffer = Ext2AllocatePool(
                         PagedPool,
                         Length + 2,
                         EXT2_FNAME_MAGIC
                     );

    if (!Target->Buffer) {
        DEBUG(DL_ERR, ( "Ex2BuildName: failed to allocate name bufer.\n"));
        return FALSE;
    }
    RtlZeroMemory(Target->Buffer, Length + 2);

    if (ParentLen) {
        RtlCopyMemory(&Target->Buffer[0],
                      Parent->Buffer,
                      ParentLen * sizeof(WCHAR));
    }

    if (bBackslash) {
        Target->Buffer[ParentLen++] = L'\\';
    }