trainee material

7/31/2019 Trainee Material

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Table of Contents

1. Basic Instruction ........................... 2

2. Code Standards ........................... 3

3. C Compiler Preprocessors ........................... 5

4. Dynamic Memory Allocation ........................... 7

5. About typedef ........................... 8

6. If-Else and its Alternatives ........................... 9

7. Structural Arrangements ........................... 14

8. Container Concept ........................... 169. How to Use VOID pointer ........................... 18

10. About Offset ........................... 20

11. Array of Pointer ........................... 21

12. About Segmentation Fault ........................... 24

13. How to make Domain Application ........................... 29

13.1. About Event ........................... 29

13.2. Structure Construction ........................... 30

13.3. Signature Construction ........................... 36

13.4. Sample Code for Signature .......................... 37


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Basic Instruction

*modularize the code.

*Use datatype as NODE for structure pointer avaiable inside the structures

The NODE is nothing but the datatype of void

typedef void NODE;

*If possible use generic pointer(void*) to write common functions,so thatwe can call the function without respect to its pointer type, And we can

retrive the data by typecast.

*Declarations should be at the top of the function, not in execution part of

the program.

*Memory allocated using malloc or calloc should be freed if it is not

not used anywhere.

*One must not free or use the chunk of memory which is already freed using

free function.It 'll raise segmentation fault.

*free function must be called to free the chunk of memory which is

created either by malloc or by calloc function.*Here we should Use linkedList to persist Data as of now.

Createing Directory

Syntax : $ mkdir FolderName

Example : $ mkdir Protech

Change to forward(fwd) Directory : $ cd folderNameChange to backward(bwd) Directory : $ cd ..

Some Commands for related Directory

Change to bwd More than 1 directory : $ cd ../../../

: $ cd ../FolderName

: $ cd FolderName/SubFolder

Createing File

Syntax : $ vi FileName.Extension

Example : $ vi Source.c

Compiling C source code:

gcc main.c (to create binary file(a.out))

gcc -c main.c (to create object file)

Vi Editor shortcuts:

V= to select a line. Press up or down arrows to select more lines.

Y= to copy the selected line(s).

p= to paste next to the current line.

Note:

Here the motto is, The code should be simple and efficient

The structures designing for Domain(like OMS,HMS,Reseller,Auditor,etc..,)

should be less memory consuming and accessing time for the data should be less.


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P= to paste Previous to the current line.

u= to undo the changes.

Ctrl+r= to redo the undone action.

Code Standards:

Our Organization has some basic formats for codings. This should be uniqueand every one should Follow this. They are given below,

In variable declaration, A variable name should contains the Prefix of the

date type declared. That is a variable name should tell that what date type

is this. For example:

int iRollNo; // integer variable

float fAmount; // float variable

char cSex; // character variable

ADDRESS oPermanentAddress; // object variable

ADDRESS *pTemporaryAddress; // pointer variable

If there is more than one word in a variable name, then each first letter of

the each word should be in Capital. For example,

Roll no ---> RollNo

Permanent address ---> PermanentAddress

Temporary address ---> TemporaryAddress

Give proper name to the variables. Using the name itself, we can

understand the role of that variable.

All Function prototype and construct the structures in Header file(*.h) notin source file(*.c).Include that header file in your source file If required.

Minimal usage of temporary variables used in a function.Mostly avoid

temporary variables inside functions.

For Functions, Function name tells that whats is going to do.If there is

more than one word in a function name, then each first letter of the each

word should be in Capital

Each Function should be written in a separate file. The filename should be

the function name.

When writing a function, think and make it as a common function. Its

useful for other domains also.

To make a common function, instead of using the structure parameter use

offsets. Its useful for other structure functions also.


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Avoid the use of if-else statements in a function. Use logical operators and

bitwise operators in a function.Instead of if-else probably Function

Pointers and Array of pointers can be used for efficiency.

A function should be written in Efficient and simple manner.

For example, strcpy() function

int strcpy(char *cSource, char *cDestination)

{

while(*cDestination != '\0')

{

*cSource = *cDestination;

cSource = cSource + 1;

cDestination = cDestination + 1;

}}

The above function is rewritten in a efficient and simple manner like this,

int strcpy(char *cSource, char *cDestination)

{

while(*cSource++ = *cDestination++) ;

}

The defined Macros should be in Uppercase.

Each function should be of Return type as int .Because to reporting error

in the funtion.You have to construct function such that if the function

return 0 means non-Error . Returns non-Zero means Error.So that

communicate with one function to other function.

Proper Error handling must be for each function. Example : NULL should

be checked for nullable variables.

Use Conditional Inclusion in the Header files.

Use -Wall while compilation to show all warnings.eg. $ gcc main.c foo.c -Wall

Input And Output codes should have separate files. Should not mingle

with any other function codes.


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C compiler preprocessors

Preprocessor commands are executed before the compiler compiles the

source code. These commands will change the original code usually to suit the operating

environment and/or to add code that will be required by calls to library functions.

Preprocessors are recognised by the leading # in their names.

Include preprocessor

The include preprocessor will add source code to your existing source. This

is used to include header files that contain function declarations.

* '< >' says to the preprocessor that the file is in the system libraries.

Example: #include

* means that this is a user defined file. Absolute or relative paths may be

defined. Example: #include "myheaders.h"

#include "/usr/home/leslim/myheaders.h"

#define preproces

The#define preprocessor allows us to define symbolic names and constants.

A quick example

#define PI 3.14159

This statement will translate every occurance of PI in the program to

3.14159. Here is a more complete example:

#define PI 3.14159

main(){

int r=10; float cir;

cir = PI * (r*r);

}


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Conditional Inclusion

Use Conditional Inclusion at the time of header file include. The #if lines

evaluates a constant integer expression (which may not include sizeof, casts or enum

constants). If the expression is non-zero, subsequent lines until an #endif or #elif or #else

are included. (The preprocessor statement #elif is like else if ). The expressiondefined(name) in a #if is 1 if the has been defined, and 0 otherwise.

Example:

#ifndef _HMSHeader_

#define _HMSHeader_

/* HMS Structures */

typedef struct Container

{

void *pNext;void *pDataPtr;

}CONTAINER;

typedef struct Todo

{

int iEntryDate;

int iTodoTask;

int iDueDate;

int iDueTime;

char cPriority; // 0-Low,1-Medium, 2-High

int iNotes;}TODO;

/* All structures will com here */

#endif


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Dynamic Memory Allocate

Malloc (memory allocation) is used to dynamically allocate memory at run

time. Possible uses for this function are

Read records of an unknown length.

Read an unknown number of database records.

Link lists.

The simplest way to reserve memory is to code something like

The example above has two problems

1) If the data is less than 1000 bytes we are wasting memory.

2) If the data is greater than 1000 bytes the program is going to crash.

3) The 1000 bytes are reserved throught out the life of the program. If this

was a long running program that rarely used the memory, it would again be wasteful

malloc allows us to allocate exactly the correct amount of memory and with

the use of free only for the time it is required.

Malloc return type is void Pointer thats we use typecast.

Calloc (memory allocation) allocates memory for an array of nmemb

elements of size bytes each and returns a pointer to the allocated memory. The memory is

set to zero

Library: stdlib.h

Prototype: void *malloc(size_t size);

Syntax: char * String; String = (char *) malloc(1000);

Main()

{

char string[1000];

strcpy(string, "Some text");

}

Syntax:

#include

void *calloc(size_t nmemb, size_t size);


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Typedef

Every variable has a data type. typedef is used to define new data type

names to make a program more readable to the programmer.

These examples are EXACTLY the same to the compiler. But the right hand

example tells the programmer the type of money he is dealing with.

Some Other type of Typedef:

1) typedef enum {FALSE=0, TRUE} Boolean

main () {

Boolean flag = TRUE;

}

2) typedef char *String;

main() {

String Text = "Thunderbird";

printf("%s\n", Text);

}

3) typedef struct {

int age;

char *name

} person;

person people;

As a final note, you can create several data types in one hit.

typedef int Pounds, Shillings, Pennies, Dollars, Cents;

Main(){

int Money;

Money=20;

}

Main(){

typedef int Pounds;

Pounds Money=20;

}


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If Else

We want check something in our Program means to use If else. Suppose

we check more than one data,in that time the Occurance ofifis more.So Our coding will

be more lenghy and Not Effective way of Program.We should follow the below

standards.

Scenario - I From HMS:

In Home Management System, To-Do Module is used to write the things we

want to do. To add a new to-do User has to enter the to-do contents ( pick up laundry,

buy flowers, pickup dad from airport etc ) and due date and time. This due date and time

is a future date and time only. If date is current date, then time should be a future one.

Screen for ToDo Module in HMS

Int IsGreater(int iFirst, int iSecond)

{

if(iFirst > iSecond)

return 1;

else

return 0;

}

int IsGreater(int iFirst, int iSecond)

{

return (iFirst > iSecond);

}

Normal way of If-Else Our Standards If-Else


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Wrong Way of Apporach

HMS To-Do Structure

typedef struct Todo

{

int iEntryDate;

int iTodoTask;int iDueDate;

int iDueTime;

char cPriority; // 0-Low, 1-Medium, 2-High

int iNotes;

}TODO;

Int RunCreateTODO(HMS *HMSRoot, TODO *Todo)

{ int i,j,date;

i=(IsCurrentDate(Todo->iDueDate));

if(i==-1) {

printf("Past Date:\n");

return 1;

}

GetCurrentDate(&date);

if(date==(Todo->iDueDate))

{

j=(IsCurrentTime(Todo->iDueTime));

if(jpTODO,(void*)Todo);

///* This function is used to add the node in List. */

return 0;

}

Tempory Variable

i,data,j

DrawBack

UnWanted Printf

I=(IsCurrentDate(Todo->iDueDate));

if(i==-1) { // Set of lines }


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In Our Apporach

Scenario - II From HMS

There are many types of expenses we make in our day to day life. For

Record that Use Expense Module in HMS. We spend some money the expense should be

less than or equal to our Cash balance or Bank balance.

Expense Screen in HMS

int RunCreateTODO(HMS *HMSRoot, TODO *Todo)

{

int iDate;

return ((((iDate = IsCurrentDate(Todo->iDueDate))==-1) ||

((iDate==0) && (IsCurrentTime(Todo->iDueTime) < 1))) ||

AssignContainer((void **)&HMSRoot->pTODO, (void*)ToDo);

}


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Sub Screen in Expense (Above Screen)


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Wrong Way of Apporach

Our Apporach

int CheckExpenseAmountWithPaymentTypeAmount

(HMS *pHMSRoot, RECIPAYMENT *pPayment, void *pBankRef)

{

if(pPayment->cReceiptPaymentType == 0)

return CheckCashBalance(pHMSRoot,pPayment);

else if( pPayment->cReceiptPaymentType == 1)

return CheckBankBalance(pHMSRoot, pPayment,pBankRef );

}

int IsFloatValueSmallOrEqual(float fFirstAmt, float fSecondAmt)

{

return fFirstAmt > fSecondAmt ;

}

int CheckCashBalance(HMS *pHMSRoot, RECIPAYMENT *pPayment)

{

return IsFloatValueSmallOrEqual(pHMSRoot->fCashBalance,pPayment->fReceiptPaymentAmount);

}

int CheckExpenseAmountWithPaymentTypeAmount

(HMS *pHMSRoot, RECIPAYMENT *pPayment, void *pBankRef)

{

int (*FnPtrCheckCashBank[])(HMS*,RECIPAYMENT *,void*) =

{ CheckCashBalance, CheckBankBalance};

return (*FnPtrCheckCashBank[(int)pPayment-> cReceiptPaymentType])

(pHMSRoot,pPayment,pBankOrCardRef);

}

Become Like that

Using Function Pointer


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Structural Arrangement

1.Reusablity

2.MemoryConception

3.Fast Access Data.

Normal Party Structure for all domain

ReUseable

Typedef struct PartyEntity{

int iPartyID;

int iName;

char cPartyType;

// Cus,Sup,Cus/Sup/Agency,If Party Config And TxnBank Config is same1bit

//char cBankConfigureStatus;

int iAsOnDate;

float fOpeningBalance;

float fCurrentBalance;

float fOverallRankOfParty;

int iPaymentOrReceiptCount[2];

int iInstrumentLastDate[7][3];

void *pPartyItemDetails; //Arranged acc to Items best response

float fDueAmount;

int iTotalTransactionCount;

int iBankTxnCount;

int iCashTxnCount;

float fAverageInstrumentAmount[2];

int iAddressLine1;

int iAddressLine2;

int iArea;

int iContactNo;int iFAXNo;

int iEMailID;//abc_xyz

int iEMailAddress;//@gmail.com

int iPANNo;

int iLicenseNo;//CST No

NODE *pLocation;//DIRECT LocationConfig(City,State,Country)

int iPinCode;

};


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Same PartyEntity But Break Address

In the above example we Break the address Node.Because in the kind ofNode to needed for all domain.Suppose its no Need means to put NULL.Null is Nothing

but 0.

If suppose one scenario To show all payment for Specfic Customer so

we kept the Payment Reference to Customer also.

CONTAINER *pPayment;

Typedef struct PartyEntity

{

int iPartyID;int iName;

char cPartyType;

// Cus,Sup,Cus/Sup/Agency,If Party Config And TxnBank Config is same1bit

//char cBankConfigureStatus;

int iAsOnDate;


float fCurrentBalance;

float fOverallRankOfParty;

int iPaymentOrReceiptCount[2];

int iInstrumentLastDate[7][3];

void *pPartyItemDetails; //Arranged acc to Items best response

float fDueAmount;

int iTotalTransactionCount;

int iBankTxnCount;int iCashTxnCount;

float fAverageInstrumentAmount[2];

container *pAddress;

};

typedef struct Address

{

int iAddressLine1;

int iAddressLine2;

int iArea;

int iContactNo;

int iFAXNo;

int iEMailID;//abc_xyz

int iEMailAddress;//@gmail.com

int iPANNo;

int iLicenseNo;//CST No

NODE *pLocation;//DIRECT LocationConfig(City,State,Country)

int iPinCode;

}ADDRESS;


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Screen for SUGAR

We entered data and click the Add Button, above all details will be store in

the Below corresponding Struct Variables its become a NODE.

After that we keep that data in our Memory so, use some DataStructure

like LinkedList,Tree,Array etc.,Here we use linked list but structural arrangement is

different.That Concept Name is CONTAINER.

CONTAINER Concept

Container is nothing but the wrapper that is List.Its have

1.DataPointer

2. Next Node Address

Typedef struct OtherIndustriesConfig{

int iItemCode;

int iItemName;

int iDistance;

int iDescription;

Node *pLocation;

}OTHERINDUSTRIESCONFIG;


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Here DataPointer is nothing but OtherIndustriesConfig Structure.Before

fill data we allocate the memory for that.

Now we make or Append that node to CONTAINER.So we make the

Container Node first

Make a Container for recently get Node.

Struct Container *pNext; ==>NULL

Struct

PotherIndustriesConfig

Address=>2004

Address=>1000

Container Node

OTHERINDUSTRIESCONFIG *pOtherIndustriesConfig;pOtherIndustriesConfig =

(OTHERINDUSTRIESCONFIG*)malloc(sizeof(OTHERINDUSTRIESCONFIG))

Typedef struct Container

{struct Container *pNext;

NODE *pDataPonter;

}


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Insert in to Container List

How to Use VOID

Typedef struct Container

{

void *pNext;NODE *pDataPonter;

}CONTAINER;

CONTAINER *pRoot,*pTemp;

void *pRoot,*pTemp;

Root=pTemp->pNext

pRoot=(void **)*pTemp

Pnext

Void **pRoot,

*(int*)*pRoot

*(int*)(((int*)*root)+1)

DataPointer

Void *pRoot,

*(int*)pRoot

*(int*)(pRoot+4)

Container

Root->pDataPointer=

pTemp->pDataPointer

*(int*)(pRoot+4)=*(int*)(Temp+4)

pNext => 1008

DataPointer =>2010

pNext => 1012

DataPointer =>2020

pNext => NULL

DataPointer =>2030

1000 1008 1016

Int AssignContainer(CONTAINER **pRoot,NODE *pNode)

{

CONTAINER *pTempContainer=(CONTAINER *)malloc(8);

pTempContainer->pDataPointer=pNode;

pTempContainer->pNext =*pRoot;

*pRoot=pTempContainer;return 0;

}


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Int AssignContainer(CONTAINER **pRoot,NODE *pNode)

{

CONTAINER *pTempContainer=(CONTAINER *)malloc(8);

pTempContainer->pDataPointer=pNode;pTempContainer->pNext =*pRoot;

*pRoot=pTempContainer;

return 0;

}

Example Code With Out Using Void

IitemCode

IitemName

Idistance

Idescription

1000

2000

1000

1004

1008

1012

Node

*pNode

*(pNode+0)

*(pNode+4)

*(pNode+8)

Void *Node;

Typedef struct OtherIndustriesConfig

{

int iItemCode;

int iItemName;int iDistance;

int iDescription;

}OTHERINDUSTRIESCONFIG;

OTHERINDUSTRIESCONFIG *pTemp;pTemp=

(OTHERINDUSTRIESCONFIG*)malloc(sizeof(OTHERINDUSTRIESCONFIG));

Node=pTemp;

Offset


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Example Code With Using Void

Offset is a Number its increment by what we mention.

*(int *)(pTempContainer+4)

Here pTempContainer increment by 4. That 4 is Offset.Itsdiffer from datatype to datatype.

Pointer Arithmentic

Increment

DataType Size Size

Of *

Increment Sample Start

Address

Sample End

Address

Int* 4 4 + + 2000 2004Float* 4 4 + + 3000 3004

Char* 1 4 + + 1000 1001

Void* 1 4 + + 300 301

Structure* Sizeof

(Struct

ure) 4

+ +

300

300+Sizeof

(Structure)

Int AssignContainer (void **pRoot,void *pNode)

{

void *pTempContainer=(int *)calloc(1,8);*(int *)(pTempContainer+4)=(int )((int *)pNode);

(int *)*(int *)pTempContainer=(int*)*pRoot;

*pRoot=(int*)pTempContainer;

return 0;

}

Insert Node

Container Create


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Decrements

DataType Size Size

Of *

Decrement Sample Start

Address

Sample End

Address

Int* 4 4 - - 2004 2000

Float* 4 4 - - 3004 3000

Char* 1 4 - - 1001 1000

Void* 1 4 - - 301 300

Structure* Sizeof

(Struct

ure) 4

- -

300

300-Sizeof

(Structure)

Array of Pointer

The way there can be an array of ints or an array of floats,similarly there

can be an array of pointers. Since a pointer variable always contains an address, an array

of pointers would be nothing but a collection of addresses. The addresses present in the

array of pointers can be addresses of isolated variables or addresses of array elements or

any other addresses. All rules that apply to an ordinary array apply to the array of

pointers as well. I think a program would clarify the concept.

In OMS(Office Mgmt System) have one scenario that is.,

The above Root is OMS Main Root.we want to insert a Node to any one SubRoot like (Enquiry,Quotation....) with respect to its type passed as its argument.There are

TWO way to insert

Typedef struct Oms{

CONTAINER *pEnquiry;

CONTAINER *pQuotation;

CONTAINER *pOrder;

CONTAINER *pDc;

CONTAINER *pInvoice;

CONTAINER *pGoodsReturn;

CONTAINER *pGRN;

}OMS;


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Normal Way

The above case we can also switch case but it is also Inefficient.

DrawBack Of Above Coding

No.Of Lines More

More Checking

if... else if

Code Repeat in every if AssignContainer

int RunCreateAndInsertInstrument(OMS *pOMSRoot,Node *pInstrument,

int iInstrumentNo)

{

if(iInstumentNo==1)

{// Enquiry Instument

AssignContainer(&pOMSRoot->pEnquiry, Node *pInstrument );

}

else if(iInstumentNo==2)

{

// Qutation Instument

AssignContainer(&pOMSRoot->pQuotation, Node *pInstrument );

}


{

// Order Instument;

AssignContainer(&pOMSRoot->pOrder, Node *pInstrument );}


{

// DC Instument;

AssignContainer(&pOMSRoot->pDC, Node *pInstrument );

}


{

// Invoice Instument;

AssignContainer(pOMSRoot->pInvoice, Node *pInstrument );

}

else if(iInstumentNo==6){

// Goods Returns Instument;

AssignContainer(&pOMSRoot->pGoodReturns, Node *pInstrument );

}


{

// GRN Instument;

AssignContainer(&pOMSRoot->pGRN, Node *pInstrument );

}

}


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we rectify the above drawbacks.Here we use Array of Pointers

Double Pointer

Int AssignContainer (void *pRoot,void *pNode)

{

void *pTempContainer=(int *)calloc(1,8);

*(int *)(pTempContainer+4)=(int )((int *)pNode);

*pRoot=InsertFirst(*pRoot,pNode);

return 0;

}

void *InsertFirst(void *pRoot,void *pNode){

(int *)*(int *)pNode=(int*)pRoot;pRoot=(int*)pNode;

return pRoot;

}

Int AssignContainer (void *pRoot,void *pNode)

{

void *pTempContainer=(int *)calloc(1,8);

*(int *)(pTempContainer+4)=(int )((int *)pNode);

InsertFirst(&pRoot,pNode);return 0;

}

void *InsertFirst(void **pRoot,void *pNode){

(int *)*(int *)pNode=(int*)*pRoot;

*pRoot=(int*)pNode;

}

int RunCreateAndInsertInstrument(OMS *pOMSRoot,Node *pInstrument,int iInstrumentNo)

{

Void *pInstrumentRoot[]={&pOMSRoot->pEnquiry,&pOMSRoot->pQuotation,

&pOMSRoot->pOrder,&pOMSRoot->pGRN,

&pOMSRoot->pDC,&pOMSRoot->pInvoice,

&pOMSRoot->pGoodsReturn};

AssignContainer(pInstrumentRoot[iInstrumentNo],pInstrument);

}

Return the Root

address

Return Type Void

Pointer

Address of Root


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How to Avoid Segmentation Fault

Fault - I

#includetypedef struct Party

{

int iPartyId;

char *cPartyName;

}Party;

int main()

{

Party *pNewParty;

printf("Pointer Addr:\t%p\n",pNewParty);

printf("PartyId:\t[%d]\nPartyName:\t[%s]\n",

pNewParty->iPartyId,pNewParty->cPartyName);

return 0;

}

Output Screen

Its Garbage Value May be here

Segment fault will occure


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Fault - II

#include

typedef struct Party

{

int iPartyId;

char *cPartyName;

}Party;

int main()

{

Party *pNewParty=NULL;


printf("PartyId:\t[%d]\nPartyName:\t[%s]\n",


return 0;

}

Output Screen


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Solution - I

#include


{

int iPartyId;

char *cPartyName;

}Party;

int main()

{


pNewParty = (Party*)malloc(sizeof(Party));

pNewParty->cPartyName = (char*)malloc(50,sizeof(char));

pNewParty->iPartyId = 10;

strcpy(pNewParty->cPartyName,"Alocious");

printf("Pointer Addr:\t%p\n",pNewParty);printf("PartyId:\t[%d]\nPartyName:\t[%s]\n",


return 0;

}

Output Screen


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Solution II

#include


{

int iPartyId;char *cPartyName;

}Party;

int main()

{


pNewParty = (Party*)malloc(sizeof(Party));

pNewParty->cPartyName = (char*)malloc(50,sizeof(char));

pNewParty->iPartyId = 10;

pNewParty->cPartyName = strdup("Alocious");


printf("PartyId:\t[%d]\nPartyName:\t[%s]\n",pNewParty->iPartyId,pNewParty->cPartyName);

return 0;

}

Output Screen


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Solution - III

#include


{

int iPartyId;char *cPartyName;

}Party;

int main()

{

Party oOldParty;

Party *pNewParty = &oOldParty;

oOldParty.cPartyName = (char*)malloc(50,sizeof(char));

oOldParty.iPartyId = 10;

strcpy(oOldParty.cPartyName,"Alocious");

printf("Pointer Addr:\t%p\n",pNewParty);printf("PartyId:\t[%d]\nPartyName:\t[%s]\n",


return 0;

}

Output Screen


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How to make a Domain Application*:

From the Domain Analyst , the Domain requirement may be came by either

as document or pdf or oral.The Programmer have to convert that requirement in to

Structures and Signatures . The structures are nothing but the group of related data for

the given domain requirement in an organized mannar.After that Using those structures

create the signatures ,The signatures are nothing but the flow of functions invoked while

tigger an event.*--> The Examples contains less content for understanding purpose.The Actual content 'll moreWhat do you meant by Event:

The Event is an action what an Applictaion 'll perform.For example, Lets

take a Domain called OMS(Office Management System).In the OMS, There are many

modules are there namely Enquiry, Quotation, Order, GRN, DC, Invoice,GoodsReturn, Party, Accounts, etc.., In that modules, It can contains the action like

search, Create, Update ,Delete, Restore, etc.., are termed as events.

If we write a function for an event means the function should be prefixed

with Run. Note that the prefix should not be suited for any other subfunction.

Each Events may or may not have set business rules or business

validation.That business rules were narrated via document or oral by Domain Analyst

For Example, we took the Enquiry, where imagine the Enquiry is you are the shopkeeper

professionally you'll enquire rate and details of some item or product from many different

shops. The enquiry which is made by you is purchase enquiry. To whom it has been

made is Supplier.When someone Enquire from you is the Sale Enquiry, the person who

enquired is termed as Customer. The customer and supplier has same set of

parameters. So, we call them as Party.

Eg for Signature(Function) naming for Events.

RunCreateEnquiry(......)

RunUpdateEnquiry(......)


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How to construct a Structure for Domain Requirement:

The construction(Design) of structures should be simplified and use to put

the variables whereever required for optimized search and minimal consumption of

memory.

Lets see some examples,First we'll take the Party screen and designstructure for it.

Screenshot:

One of the Event

Parameters


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Typedef struct PartyEntity{int iPartyID;

int iName;

/* cPartyType - 2-bit--[0-customer/1-supplier/2-Both]

- 2-bit--[Company Classification]

[ 0-Manufacture/1-Industry

/2-SEZ /3-Others]

*/

char cPartyType;

Container *pPartyAddress;

int iContactPerson;

int iContactNo;

int iMobileNo;

int iFAXNo;

int iEMailId;

Node *pTaxOrientedNo;

int iAsOnDate;


float fDueAmount;

NODE *pSalesInstrument;

NODE *pPurchaseInstrument;

}PartyEntity;

Char cPartyType-- Here this

parameter holds 2 parameter

value as described above in Blue

color Font.If write a normal mean

it'll like below

char cType;

char cCompanyClassification

Because of this one byte'll be

wasted. So while designing

structures you have to combined

the parameter like this.To avoid

wastage. This is applicable only

parameters having defined value

This variable is designed as a pointer

Because that variable holds Tax

oriented nos like (PAN No,TIN No,

CST No,etc).But all party donot have

this so here minimal wastage of

memory.Due to the memory 'll be

created when those no exist.

The variable is not given by DomainAnalyst.But the Developer has to

thing and introduce some variables

like this.For fast Retrival due for the

party. Introduce variables whereever

it required.Keep it mind This is for

fast access.

These 2 variables means where the party

do any transaction'll be pushed here.so

that we can retrive all the transaction

made by the party.. We can as simply say

it as an Object in OOPs concept.If we

take a party we can get records with

respect to him.

Typedef struct SaleInstrument

{

Container *pEnquiry[3];

Container *pQuotation[3];

Container *pOrder[3];

Container *pDC[3];

Container *pInvoice[3];

Container *pGoodsReturn[3];

Container *pPaymentOrReceipt[2];

}SalesInstrument;


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Lets take another Example Enquiry :

screenshot:

The Item should be list because One Enquiry

may contain many items

Decides Purchase or Sales flow


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Typedef struct ItemDetails

{

Node *pItemRef; // StockItemRef or PreviousItemRef

char cStatus; // 0 - StockRef, 1 - PrevItemRef

int iDescription;

float fQuantity;

int iUOM;

}ItemDetails;

typedef struct EnqQuoOrdItem

{

ItemDetails pItemDetails;

float fRateUOM;}EnqQuoOrdItem;

typedef struct Enquiry

{

int iNo;

int iDate;

int iRemarks;

char cStatus;

Container *pEnqQuoOrdItem;

Node *pParty;Container *pNextInstrument;

}Enquiry;


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Lets see for quotation: Load the Previous Enquiry. If the user made

the quotation with respect to Enquiry


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Typedef struct Quotation

{

int iNo;int iDate;

int iRemarks;

char cStatus;

Container *pEnqQuoOrdItem;

union{

Node *pParty;

Container *pPrevInstrument;

};

Container *pNextInstrument;Node *pTermsConditions;

float fTotAmtPerUOM;

}Quotation;

Here We use union, Because the quotation

can be made via Enquiry or Directly. If

quotation is come via Enquiry means that

Enquiry Node in the variable

pPrevInstrument and If Direct means

holds party in the variable pParty.

The cStatus 'll give information about what

is stored

typedef struct OMS

{

CONTAINER *pCompanyProfile;

CONTAINER *pParty[3];

CONTAINER *pEnquiry[2][3];

CONTAINER *pQuotation[2][3];

}OMS;

pParty ,Here the party is in array because

as we already discussed the party 'll

Customer,Supplier,Both..,With respect to

the party Type the party node'll be inserte

in respective index.

Each part Domain has its main structure,as simply

says that is the database for that domain, it contains

all the root pointer or head pointer if required

when an event is triggered the checking also go

from here and the final node should be inserted in

corresponding root if required

Enquiry

node 'll be

inserted Here

Quotation

node 'll be

inserted Here

This array for sales

and Purchase

This array for current

status of that Instrument

Pending/moved/closed


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How to construct signatures:

The signatures are nothing but the function prototypes, which is used to

satisfy the domain requirement or business needs.When an event(create,update..)

triggered an set of functions should be called those functions are arranged in a flow with

its prototype using that flow itself we can check whether the event 'll completely work ornot.Actually the construction of signatures is equivalent to code.Let see how to construct.

'll we take the Party for the event Create(Save).

On save of party we've to check the following things.Note that the business

rules which mentioned below is minimal for understanding purpose.But the actual

content 'll be more.

1. Check whether the party is already exist

2. Generate the unique Id for the party.

3. Check whether the AsOnDate is not future date.

4. Check whether the AsOnDate is not lesser that Company start date.

int RunCreateParty(OMS *OMSRoot,PartyEntity *pInputParty);

int IsValidAsOnDate(int iCompanyProfileDate,int iAsOnDate);

int IsNotFutureDate(int iAsOnDate);

int GetCurrentDate(int *iCurrentDate);

int IsGreaterThanOrEqual(int iAsOnDate,int iCompanyProfileDate);int GetBitStream(int cPartyType,int iBitPattern,int *pPartyType);

int IsPartyAlreadyExist(CONTAINER *pPartyRoot,int iPartyName);

------If all the above condition TRUE.

int SetUniqueId(int *iPartyId,int iModuleNo);

int CreateAndCopyPartyNode(PartyEntity **pPartyNode,PartyEntity *pInputParty);

int AssignContainer(CONTAINER **pPartyRoot,NODE *pPartyNode);

These are the business rules tobe considered

while creating a party.If it fails the operations

should be aborted.

After the business rules satisfies an Unique Id should be created and

and allocate the memory for the party because while we get from user

we can't assure that the node is created by using malloc or calloc.so

create a node and copy the contents from input node to new node.

After that we have to persist the data so Insert the new node in the party root

in the OMSRoot w.r.t. its type.

Is- When the function

characteristic'll be 0 or 1

i.e.., True or False


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Codes for above Signatures:

Note: Error means return Non-Zero,Success means return Zero

Every function should follows.

Normal RunCreateParty Code:

Int RunCreateParty(OMS *pOMSRoot,PartyEntity *pInputParty)

{

PartyEntity *pPartyNode=NULL;

int iPartyType = 0 ;

if(!pInputParty || !pOMSRoot)

return -1;

if(!pOMSRoot->pCompanyConfig)

return 1;

if( IsValidAsOnDate(pOMSRoot->pCompanyConfig->iCompanyStartDate,

pInputParty->iAsOnDate) )

return 1;

GetBitStream(pInputParty->cPartyType,0x3,&iPartyType);

if( !IsPartyAlreadyExist(pOMSRoot->pParty[iPartyType],pInputParty->iPartyName))

return 1;

SetUniqueId(&pInputParty->iPartyId,1);

CreateAndCopyPartyNode(&pPartyNode,pInputParty);

AssignContainer(&pOMSRoot->pParty[iPartyType]),pPartyNode);

return 0;

}

Our Expectational Style:

Int RunCreateParty(OMS *pOMSRoot,PartyEntity *pInputParty)

{

PartyEntity *pPartyNode=NULL;

int iPartyType = 0 ;

if(!pInputParty || !pOMSRoot)

return -1;

if(!pOMSRoot->pCompanyConfig)

return 1;

return ( IsValidAsOnDate(pOMSRoot->pCompanyConfig->iCompanyStartDate,pInputParty->iAsOnDate)|| (GetBitStream(pInputParty->cPartyType,0x3,&iPartyType))

|| (!IsPartyAlreadyExist(pOMSRoot->pParty[iPartyType],pInputParty->iPartyName))

|| (SetUniqueId(&pInputParty->iPartyId,1))

|| (CreateAndCopyPartyNode(&pPartyNode,pInputParty))

|| (AssignContainer(&pOMSRoot->pParty[iPartyType]),pPartyNode));

}


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Normal IsValidAsOnDate Code:

Int IsValidAsOnDate(int iDate,int iAsOnDate){

if( !IsFutureDate(iAsOnDate) )

return 1;

if( IsLesser(iAsOnDate,iDate) // If Error Returns in Lesser means GreaterThanOrEqual.

return 0;

return 1;

}

int IsFutureDate(int iAsOnDate)

{

int iCurrentDate = 0;GetCurrentDate(&iCurrentDate);

if( IsGreater(iAsOnDate,iCurrentDate) ) // If Error in Greater Means LesserThanOrEqual

return 1;

return 0;

}

int IsLesser(int iLesser,int iNonLesser)

{

if( iLesser < iNonLesser)

return 0;return 1;

}

int IsGreater(int iGreater,int iNonGreater)

{

if( iGreater > iNonGreater)

return 0;

return 1;

}


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Our Expectational IsValidAsOnDate Code:

Int IsValidAsOnDate(int iDate,int iAsOnDate){

return ( !IsFutureDate(iAsOnDate) ) || ( !IsLesser(iAsOnDate,iDate) );

}

int IsFutureDate(int iAsOnDate)

{

int iCurrentDate = 0;

GetCurrentDate(&iCurrentDate);

return ( IsGreater(iAsOnDate,iCurrentDate) );

}

int IsLesser(int iLesser,int iNonLesser)

{

return !( iLesser < iNonLesser);

}

int IsGreater(int iGreater,int iNonGreater)

{

return !( iGreater > iNonGreater);

}


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For Practice:

1. Make the IsPartyAlreadyExist into COMMON function with reference to the

previous sections.

2. Use to make GetBitStream and SetBitStream with your own Parameters.

Int IsPartyAlreadyExist(CONTAINER *pPartyRoot,int iPartyName)

{

while( pPartyRoot && ( ((PartyEntity*)pPartyRoot->pDataPtr)->iPartyName != iPartyName))

pPartyRoot = pPartyRoot->pNext;

return !(pPartyRoot);

}

int CreateAndCopyPartyNode(PartyEntity **pPartyNode,PartyEntity *pInput)

{

*pPartyNode = (PartyEntity*)calloc(1,sizeof(PartyEntity));

memcpy(*pPartyNode,pInput,sizeof(PartyEntity));

return 0;

}

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