alg : 找1 to N的质数(筛法)
算法思路参考 :
质数筛法 : http://blog.csdn.net/program_think/article/details/7032600
在驱动层实现了一个质数筛法.
/// @file Function.h /// @brief 功能的实现 #ifndef __FUNCTION_H__ #define __FUNCTION_H__ #include <ntddk.h> #ifndef BYTE #define BYTE unsigned char #endif #define BYTE_BITS 8 #define BYTE_BITS_MASK(x) (1 << x) /// @fn PrintPerime /// @brief 打印 0~nMax 之间的质数, 用筛法实现 void PrintPerime(size_t nMax); /// @fn MakePerime /// @brief 制作质数Buffer void MakePerime(size_t nMax, BYTE * pcPerime, size_t nBufLenPerime); /// @fn ShowPerime /// @brief 打印质数Buffer void ShowPerime(size_t nMax, BYTE * pcPerime, size_t nBufLenPerime); /// @fn IsNumberPerime /// @brief 判断一个数是否是质数 BOOLEAN IsNumberPerime(size_t nNumber, BYTE * pcPerime, size_t nBufLenPerime); /// @fn IsNumberPerimeFlag /// @brief 判断一个数是否是质数标记 BOOLEAN IsNumberPerimeFlag(size_t nNumber, BYTE * pcPerime, size_t nBufLenPerime); /// @fn SetMultipleValue /// @brief 设置nNumber倍数的值为bVal void SetMultipleValue(size_t nNumber, BOOLEAN bVal, BYTE * pcPerime, size_t nBufLenPerime); /// @fn SetNumberValue /// @brief 设置nNumber的值为bVal void SetNumberValue(size_t nNumber, BOOLEAN bVal, BYTE * pcPerime, size_t nBufLenPerime); /// @fn IsNumberNeedSkip /// @brief 是否为需要逃过判断的数, 0, 1, 不需要判断质数 BOOLEAN IsNumberNeedSkip(size_t nNumber); #endif
/// @file Function.c
/// @brief 功能的实现
#include "Function.h"
void PrintPerime(size_t nMax)
{
/// 用1Bit代表一个数, 1Byte代表8个数, 用N Bytes 代表 0~nMax
size_t nByteNumber = (nMax - nMax % 8) / 8 + ((0 == (nMax % 8)) ? 0 : 1);
BYTE * pcPerime = ExAllocatePoolWithTag(PagedPool, nByteNumber, 'PRIM');
if (NULL == pcPerime)
{
DbgPrint("NULL == pcPerime\r\n");
return;
}
memset(pcPerime, 0xff, nByteNumber); ///< 假设所有的数都是质数
/// 设置0, 1不是素数为初始条件
SetNumberValue(0, FALSE, pcPerime, nByteNumber);
SetNumberValue(1, FALSE, pcPerime, nByteNumber);
MakePerime(nMax, pcPerime, nByteNumber);
ShowPerime(nMax, pcPerime, nByteNumber);
ExFreePool(pcPerime);
}
void MakePerime(size_t nMax, BYTE * pcPerime, size_t nBufLenPerime)
{
/// pcPerime 给定的值都是质数标记
size_t nLoop = 0; ///< Buffer的循环
size_t nLoopByte = 0; ///< Buffer中字节的循环
size_t nNumberCur = 0; ///< 当前位代表的数字, 如果是质数, 直接打印出来
for (nLoop = 0; nLoop <nBufLenPerime; nLoop++)
{
for (nLoopByte = 0; nLoopByte < BYTE_BITS; nLoopByte++)
{
if (!IsNumberPerime(nNumberCur, pcPerime, nBufLenPerime))
SetNumberValue(nNumberCur, FALSE, pcPerime, nBufLenPerime);
SetMultipleValue(nNumberCur, FALSE, pcPerime, nBufLenPerime); ///< 每个数的倍数都不是质数
if (nNumberCur++ >= nMax)
break;
}
}
}
BOOLEAN IsNumberNeedSkip(size_t nNumber)
{
return ((0 == nNumber) || (1 == nNumber));
}
void SetNumberValue(size_t nNumber, BOOLEAN bVal, BYTE * pcPerime, size_t nBufLenPerime)
{
size_t nBytesPosBit = nNumber % BYTE_BITS; ///< 在该字节的位(位置)
size_t nBytesPos = (nNumber - nBytesPosBit) / BYTE_BITS; ///< 在Buffer中的字节位置
if (bVal)
*(pcPerime + nBytesPos) |= BYTE_BITS_MASK(nBytesPosBit);
else
*(pcPerime + nBytesPos) &= ~(BYTE_BITS_MASK(nBytesPosBit));
}
void SetMultipleValue(size_t nNumber, BOOLEAN bVal, BYTE * pcPerime, size_t nBufLenPerime)
{
size_t nLoop = 0; ///< Buffer的循环
size_t nLoopByte = 0; ///< Buffer中字节的循环
size_t nNumberCur = 0; ///< 当前位代表的数字, 如果是质数, 直接打印出来
size_t nBytesPosBit = 0; ///< 在该字节的位(位置)
size_t nBytesPos = 0; ///< 在Buffer中的字节位置
if (IsNumberNeedSkip(nNumber))
return;
nBytesPosBit = nNumber % BYTE_BITS;
nBytesPos = (nNumber - nBytesPosBit) / BYTE_BITS;
nNumberCur = nBytesPos * BYTE_BITS + nBytesPosBit;
for (nLoop = nBytesPos; nLoop <nBufLenPerime; nLoop++)
{
for (nLoopByte = nBytesPosBit; nLoopByte < BYTE_BITS; nLoopByte++)
{
if (nNumberCur <= nNumber) ///< 不包括设置nNumber
{
nNumberCur++;
continue;
}
if (0 == (nNumberCur % nNumber))
{
/// 当前数能被nNumber整除, 是nNumber的倍数
SetNumberValue(nNumberCur, bVal, pcPerime, nBufLenPerime);
}
nNumberCur++;
}
nBytesPosBit = 0; ///< 除了第一次使用, 都是从0开始
}
}
BOOLEAN IsNumberPerimeFlag(size_t nNumber, BYTE * pcPerime, size_t nBufLenPerime)
{
size_t nBytesPosBit = nNumber % BYTE_BITS; ///< 在该字节的位(位置)
size_t nBytesPos = (nNumber - nBytesPosBit) / BYTE_BITS; ///< 在Buffer中的字节位置
if (IsNumberNeedSkip(nNumber))
return FALSE;
return (0 == (*(pcPerime + nBytesPos) & BYTE_BITS_MASK(nBytesPosBit))) ? FALSE : TRUE;
}
BOOLEAN IsNumberPerime(size_t nNumber, BYTE * pcPerime, size_t nBufLenPerime)
{
BOOLEAN bIsPerime = TRUE;
size_t nPos = 0;
size_t nPosMax = 0;
size_t nBytesPosBit = nNumber % BYTE_BITS; ///< 在该字节的位(位置)
size_t nBytesPos = (nNumber - nBytesPosBit) / BYTE_BITS; ///< 在Buffer中的字节位置
if (!IsNumberPerimeFlag(nNumber, pcPerime, nBufLenPerime))
return FALSE; ///< 如果已经被前面的操作置为"非质数", 直接返回"非质数"
/// 在nNumber之前的数都已经正确的标记了是否为质数
/// 只有一半以下的数， 有可能被整除
nPosMax = (size_t)((nNumber - (nNumber % 2)) / 2);
for (nPos = 2; nPos <= nPosMax; nPos++)
{
if (!IsNumberPerimeFlag(nPos, pcPerime, nBufLenPerime)) ///< 不是质数不用整除
continue;
if ((nNumber % nPos) == 0)
{
bIsPerime = FALSE;
break;
}
}
return bIsPerime;
}
void ShowPerime(size_t nMax, BYTE * pcPerime, size_t nBufLenPerime)
{
size_t nLoop = 0; ///< Buffer的循环
size_t nLoopByte = 0; ///< Buffer中字节的循环
size_t nNumberCur = 0; ///< 当前位代表的数字, 如果是质数, 直接打印出来
for (nLoop = 0; nLoop <nBufLenPerime; nLoop++)
{
for (nLoopByte = 0; nLoopByte < BYTE_BITS; nLoopByte++)
{
if ((*(pcPerime + nLoop) & BYTE_BITS_MASK(nLoopByte)) > 0)
DbgPrint("%d\r\n", nNumberCur);
if (nNumberCur++ >= nMax)
break;
}
}
}
调用 PrintPerime
/// @file sys.c
/// @brief 驱动主程序
#include <ntddk.h>
#include "Function.h"
#define MODULE_NAME L"DrvDemo"
#define DRIVER_NAME MODULE_NAME L".sys"
#define DEVICE_NAME_GLOBAL L"\\\\.\\" MODULE_NAME
#define DEVICE_NAME L"\\device\\" MODULE_NAME
#define LINK_NAME L"\\dosDevices\\" MODULE_NAME
NTSTATUS DispatchCommon(PDEVICE_OBJECT pDeviceObject, PIRP pIrp);
VOID DriverUnload(PDRIVER_OBJECT pDriverObject);
NTSTATUS DriverEntry(IN PDRIVER_OBJECT pDriverObject,
IN PUNICODE_STRING pRegPath)
{
size_t nIndex = 0;
/// 找出40000以内的素数（筛法）
size_t nReqPerimeMax = 40000; ///< 求质数的范围上限
NTSTATUS ntStatus = STATUS_SUCCESS;
PDEVICE_OBJECT pDeviceObject = NULL;
UNICODE_STRING ustrDeviceName = {0};
UNICODE_STRING ustrLinkName = {0};
DbgPrint(">> DriverEntry\r\n");
RtlInitUnicodeString(&ustrDeviceName, DEVICE_NAME);
RtlInitUnicodeString(&ustrLinkName, LINK_NAME);
ntStatus = IoCreateDevice(
pDriverObject,
0,
&ustrDeviceName,
FILE_DEVICE_UNKNOWN,
0,
FALSE,
&pDeviceObject);
if (!NT_SUCCESS(ntStatus))
{
DbgPrint("<< DriverEntry : error IoCreateDevice\r\n");
return ntStatus;
}
pDeviceObject->Flags |= DO_BUFFERED_IO;
ntStatus = IoCreateSymbolicLink(
&ustrLinkName,
&ustrDeviceName);
if (!NT_SUCCESS(ntStatus))
{
DbgPrint("<< DriverEntry : error IoDeleteDevice\r\n");
IoDeleteDevice(pDeviceObject);
return ntStatus;
}
for(nIndex = 0; nIndex < IRP_MJ_MAXIMUM_FUNCTION; nIndex++)
{
pDriverObject->MajorFunction[nIndex] = DispatchCommon;
}
pDriverObject->DriverUnload = DriverUnload;
PrintPerime(nReqPerimeMax); /// 找出nReqPerimeMax以内的素数（筛法）
DbgPrint("<< DriverEntry\r\n");
return STATUS_SUCCESS;
}
VOID DriverUnload(PDRIVER_OBJECT pDriverObject)
{
UNICODE_STRING ustrLinkName = {0};
DbgPrint(">> DriverUnload\r\n");
RtlInitUnicodeString(&ustrLinkName, LINK_NAME);
IoDeleteDevice(pDriverObject->DeviceObject);
IoDeleteSymbolicLink(&ustrLinkName);
DbgPrint("<< DriverUnload\r\n");
}
NTSTATUS DispatchCommon(PDEVICE_OBJECT pDeviceObject, PIRP pIrp)
{
pIrp->IoStatus.Information = 0;
pIrp->IoStatus.Status = STATUS_SUCCESS;
IoCompleteRequest(pIrp, IO_NO_INCREMENT);
return STATUS_SUCCESS;
}
实验截图:
