Thread: String var corrupted after strcpy from another string

Yeah, I was trying to simplify it because it's gonna be lengthy, but oh well...there you go.
And sometimes, it displays

"Unhandled exception at 0x530a3330 in PCD2Assignment.exe: 0xC0000005: Access violation."

But this is not always the case. If replaced salesman_quarter[0].highest_id with another char var like id[6], it will appear the Stacked Around Variable 'id' corrupted error, or it will display
the id then followed by a bunch of junk values.

ps: Please ignore the previous codes.

Code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define     displayField            "%s %14s %14s %14s %14s %21s","Salesman ID", "Qtr1", "Qtr2", "Qtr3", "Qtr4", "Total Sales"
#define  qtrSales_Total            salesman_quarter[i].quarter_sales_total = salesman_quarter[i].quarter_sales[0] + salesman_quarter[i].quarter_sales[1] + salesman_quarter[i].quarter_sales[2] + salesman_quarter[i].quarter_sales[3]
#define     qtrSales_GrandTotal    salesman_quarter[0].grand_total += salesman_quarter[i].quarter_sales_total
#define     qtrSales_AvgSales        salesman_quarter[0].avg_sale = salesman_quarter[0].grand_total / SIZE
#define     getID_Sales            salesman_quarter[i].id, &salesman_quarter[i].quarter_sales[0], &salesman_quarter[i].quarter_sales[1], &salesman_quarter[i].quarter_sales[2], &salesman_quarter[i].quarter_sales[3]
#define     printID_Sales            salesman_quarter[i].id, salesman_quarter[i].quarter_sales[0], salesman_quarter[i].quarter_sales[1], salesman_quarter[i].quarter_sales[2], salesman_quarter[i].quarter_sales[3],salesman_quarter[i].quarter_sales_total

int QtrReport();

typedef struct
{
    char id[6];
    char highest_id[6];
    float quarter_sales[4];
    float quarter_sales_total;
    float highest_sale;
    float avg_sale;
    float grand_total;
}QUARTER;


int QtrReport()
{
    //Local Variables
    int selection;
    int SIZE=2;
        int salesman_num=3;
    char id[6]=" ";
    FILE *salesPtr;
    FILE *memoryPtr;
    
    
    //Open memory for reading previous SIZE
    memoryPtr=fopen("memory.txt","r");
    fscanf(memoryPtr, "%d", &SIZE);
    fclose(memoryPtr);
    //read


    //Open memory for storing latest SIZE for future uses
    memoryPtr= fopen("memory.txt","w");
    if(salesman_num>0)
    {
        SIZE += salesman_num;
        fprintf(memoryPtr, "%d", SIZE);
    }
    fclose(memoryPtr);
    //write


    //Open memory for reading SIZE to control the Loop for     printing out information
    memoryPtr=fopen("memory.txt","r");
    fscanf(memoryPtr, "%d", &SIZE);
    fclose(memoryPtr);
    //read
    
    //Open sales for reading in the infos & validate
    salesPtr = fopen("sales.txt", "r");
    if(!salesPtr)
    {
        printf("ERROR");
        system("pause");
        exit(-1);
    }


    printf(displayField);
    while(!feof(salesPtr))
    {
        for(i=0;i<SIZE;i++)
        {
            fscanf(salesPtr, "%[^|]|RM%f|RM%f|RM%f|RM%f", getID_Sales);
            qtrSales_Total;
            qtrSales_GrandTotal;
            qtrSales_AvgSales;
            printf("\n%s %20.2f %15.2f %15.2f %15.2f%15.2f", printID_Sales);
        }//for
            
    }//while


    for(j=0;j<SIZE;j++)
    {
        if(salesman_quarter[0].highest_sale < salesman_quarter[j].quarter_sales_total)
        {
            salesman_quarter[0].highest_sale = salesman_quarter[j].quarter_sales_total;
            strcpy(salesman_quarter[0].highest_id,salesman_quarter[j].id);
        }//if
    }//for


    printf("\n\nAverage sale by all salesmen is RM%.2f",salesman_quarter[0].avg_sale);
    printf("\nHighest sale RM%.2f is achieved by %s\n\n", salesman_quarter[0].highest_sale,salesman_quarter[0].highest_id);
            
    fclose(salesPtr);
    system("pause");
    system("cls");
    return SIZE;
    
    
}

int main(void)
{
   int holder;

   holder=QtrReport();
   return 0;
}

xeon, that code will not even compile. It is apparently making use of an array named salesman_quarter, but no such array is ever defined.

You are trying to unroll loops, and to construct multiple arguments for function calls, using macros. Such techniques make your code extremely difficult for a mere mortal to diagnose.


I suggest

1) Eliminate the macro trickery. It makes your code harder to get right and (if you manage to get it right) fragile if you ever need to change it. The particular tricks you are using are a really bad idea.

2) Try eliminating code in order to create a SMALL but COMPLETE sample of ACTUAL code that exhibits your problems when compiled and run. In the process of creating that sample, you might realise what the problem is - and not need further help. Worst case is that you will end up with a sample of code that doesn't rely on other people to do mental gymnastics - so someone can probably then provide useful help.