CriticalSection.zip_ThisIsHow_session资源-CSDN文库

共1个文件

doc：1个

版权申诉

session

101 浏览量 2022-09-22 18:47:34 上传评论收藏 14KB ZIP 举报

资源推荐

资源详情

资源评论

收起资源包目录

CriticalSection.zip （1个子文件）

CriticalSection.doc 170KB

Critical Section

The critical section object is a synchronization object that can be used for mutual exclusion

amongst threads of a single process. The critical section object is not a kernel object. The

critical section object is first created by initializing a CRITICAL_SECTION structure with the

InitializeCriticalSection function. The CRITICAL_SECTION structure is opaque and is not

meant to be public. The function EnterCriticalSection function blocks until no other thread is

in the critical section. After a thread has finished inside the critical section, it calls the

LeaveCriticalSection function. The TryEnterCriticalSection function is a non-blocking

function that can be used to test entry to a critical section code. Finally, the

DeleteCriticalSection function is used to delete the critical section object. These critical section

functions are very efficient and are more usable then the interlocked synchronization functions.

Proto-Type

VOID InitializeCriticalSection

(

LPCRITICAL_SECTION lpCriticalSection

// address of critical section object

);

Info:

The function initializes a critical section object through the

CRITICAL_SECTION structure.

Proto-Type

VOID EnterCriticalSection

(

LPCRITICAL_SECTION lpCriticalSection

// address of critical section object

);

Info:

The function blocks till entry to critical section of code is permited. The

function will not block, if the thread has already entered the critical section

code.

Proto-Type

VOID LeaveCriticalSection

(

LPCRITICAL_SECTION lpCriticalSection

// address of critical section object

);

Info:

The function can be called when a thread is about to leave a critical section of

code.

Proto-Type

VOID DeleteCriticalSection

(

LPCRITICAL_SECTION lpCriticalSection

// address of critical section object

);

Info:

The function deletes the critical section object through the

CRITICAL_SECTION structure.

Proto-Type

BOOL TryEnterCriticalSection

(

LPCRITICAL_SECTION lpCriticalSection

// address of critical section object

);

Info:

The function attempts to enter the critical section of code. If the function

succeeds, the return value is TRUE. If another thread is in the critical section,

the return value is FALSE.

The following program demonstrates an example of using an critical section object. Four

threads all try to enter the critical section code.

// Example of Critical Section Object

#include <windows.h>

#include <stdio.h>

#include <stdlib.h>

#include <assert.h>

CRITICAL_SECTION cs; // shared structure

///////////// Thread Main ///////////////////////

void ThreadMain(char *name)

{

for(;;)

{

EnterCriticalSection(&cs);

/// Critical Section of Code

printf("I %s am in critical Section\n",name);

Sleep(1000);

LeaveCriticalSection(&cs);

}

///////////////////// Create A Child//////////////

HANDLE CreateChild(char *name)

{ HANDLE hThread; DWORD dwId;

hThread=CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)ThreadMain

,(LPVOID)name,0,&dwId); assert(hThread!=NULL);

return hThread;

}

//////////////////// Main ///////////////////////

int main(void)

{ HANDLE hT[4];

InitializeCriticalSection(&cs);

hT[0]=CreateChild("Jasmine"); hT[1]=CreateChild("Jane");

hT[2]=CreateChild("Jill"); hT[3]=CreateChild("Jess");

WaitForMultipleObjects(4,hT,TRUE,INFINITE);

CloseHandle(hT[0]); CloseHandle(hT[1]);

CloseHandle(hT[2]); CloseHandle(hT[3]);

DeleteCriticalSection(&cs); return 0;

}

The next program is a slight modification of the last program. All the threads attempt to enter

the critical section of code. If they can not enter, they just printout that they are waiting to enter

the critical section code.

// The TryEnterCriticalSection Example

#include <windows.h>

#include <stdio.h>

#include <stdlib.h>

#include <assert.h>

CRITICAL_SECTION cs;

///////////// Thread Main ///////////////////////

void ThreadMain(char *name)

{

for(;;)

{

while(TryEnterCriticalSection(&cs)==FALSE)

{ printf("%s is waiting\n",name); }

/// Critical Section of Code

printf("I %s am in critical Section\n",name);

Sleep(1000);

LeaveCriticalSection(&cs);

}

///////////////////// Create A Child//////////////

HANDLE CreateChild(char *name)

{ HANDLE hThread; DWORD dwId;

hThread=CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)ThreadMain

,(LPVOID)name,0,&dwId); assert(hThread!=NULL);

return hThread;

}

//////////////////// Main ///////////////////////

int main(void)

{ HANDLE hT[4];

InitializeCriticalSection(&cs);

hT[0]=CreateChild("Jasmine"); hT[1]=CreateChild("Jane");

hT[2]=CreateChild("Jill"); hT[3]=CreateChild("Jess");

WaitForMultipleObjects(4,hT,TRUE,INFINITE);

CloseHandle(hT[0]); CloseHandle(hT[1]);

CloseHandle(hT[2]); CloseHandle(hT[3]);

DeleteCriticalSection(&cs); return 0;

}

Tutorial contains four steps:

� Step 1 - posting registered window message with HWND_BROADCAST parameter to notify

other instances when text is changed.

� Step 2 - using memory-mapped file to set the same text in all instances.

� Step 3 - synchronizing access to common memory block between all instances.

� Step 4 - advanced synchronization using inter-process Single Writer/Multiple Reader

Guard. (New)

The projects are built using MFC, this allows to concentrate on interprocess communication

features and not on boring implementation details.

Step 1. Notification.

On this step we build dialog-based application which notifies other instances that text in edit box

is changed by user. Dialog which receives such message handles it by some way - for example,

adds "*" to text in edit box.

� Create new MFC dialog-based application. Call in SameText. Remove Cancel button

from dialog template; set "Close" text to IDOK button. Add edit box to dialog and set it's

ID to IDC_EDIT_BOX. Arrange controls on dialog template.

� Using MFC Class Wizard, add member CEdit m_edit_box to CSameTextDlg class.

Member is connected to IDC_EDIT_BOX edit box.

� Add protected member BOOL m_bNotify to CSameTextDlg class and set it to TRUE in

constructor. This member will be used in EN_CHANGE message handler to prevent program

reaction when text in edit box is changed by SetWindowText and not by user.

� Add next constant to the start of SameTextDlg.cpp file:

Collapse

// Registered window message posted when user changes text in edit box

const UINT wm_Message =

RegisterWindowMessage(_T("CC667211-7CE9-40c5-809A-1DA48E4014C4"));

String constant is copied using GUIDGen utility which comes with Microsoft Visual

Studio.

� Using MFC Class Wizard, add EN_CHANGE message handler to CSameTextDlg class for

IDC_EDIT_BOX control. This function is called when user changes text in edit box.

� Add manually handling of registered window message wm_Message to CSameTextDlg

class. Add OnMessageTextChanged function definition to SameTextDlg.h:

评论收藏

内容反馈

版权申诉

朱moyimi

粉丝: 65
资源: 1万+

CriticalSection.zip_This Is How_session

最新资源

CriticalSection.zip_This Is How_session

criticalsection.rar_CriticalSection_critical

Critical-section.zip_critical_临界区

CriticalSection.rar_easy

CriticalSection.rar_CCriticalSection_CriticalSection

CriticalSection.rar_CriticalSection_线程临界区

CriticalSection.rar_CriticalSection

Critical_Sections.rar_Critical Section_DEMO

critical-section.gz_critical_临界区_线程临界区

criticalsection.zip_Windows编程_Windows_Unix_

guanjianlujing.zip_critical_critical path

critical_path-关键路径-邻接表有向图.zip_AdjListDirNetwork.h_C++ 有向图_buffal

Zotero-5.0.96.2_setup.zip

JAVA_RMI_Win.zip_The Bat_rmi

dbscan.zip_DBSCAN_DBScan java_NOISE_spatial clustering_threshold

cpm.zip_CPM C/C++_cpm_zip

Examples_critical_region.rar_critical_临界区_线程临界区

CriticalSection.rar_进程与线程_Visual_C++_

1.rar_Critical Theory_site:www.pudn.com_机器人_语音特征

ViewIE V1.01

冰河的渗透实战笔记-冰河.pdf

大灰狼远控2021最新版，解压密码222

J-LINK V10 V11固件.rar

ISO21434.pdf

Web安全漏洞扫描工具-AWVS14

stm32f103 adc采样+dma传输+fft处理 频率计_fft处理_stm32_ADCFFT_频率计_ADC采样_

CTF 竞赛入门指南（ctf-all-in-one）.pdf

Web中间件常见漏洞总结.pdf

jts-1.14.zip

CobaltStrike4.4.zip

最新资源

stm32f103 adc采样+dma传输+fft处理频率计_fft处理_stm32_ADCFFT_频率计_ADC采样_