Thread: Usage of Structs between Various files is not working

I have four .c files and 1 .h file. Please bear with me, the problem is only on one line. First a bit of context:

main.c

Code:

#include <stdlib.h>#include <stdio.h>
#include "headerfile.h"


int main(){
    char* postfix;
    char* infixedUserInput = getKeyboardInput();
    postfix = convertToPostfix(infixedUserInput);
    return 0;
}

stackUtilities.c

Code:

#include <stdio.h>#include <stdlib.h>


#define MAX_STACK_SIZE 100
#define OPENING_PARENTHESIS (


struct NumStack operandStack = {.stackPointer = 0);
struct CharStack operatorStack = {.stackPointer = 0};


void pushNum(struct NumStack *stack, double pushedValue){
    if (stack -> stackPointer < MAX_STACK_SIZE) {
        stack -> stackValue[stack -> stackPointer++] = pushedValue;
    }
    else {
        fprintf(stderr, "Number Stack full, can't push %g\n", pushedValue);
        exit(-1);
    }
}


double popNum(struct NumStack stack){
    if (stack.stackPointer > 0){
        return stack.stackValue[--stack.stackPointer];
    }
    else {
        fprintf(stderr, "Number Stack empty\n");
        exit(-1);
    }
}


void pushChar(struct CharStack *stack, char pushedValue){
    if (stack -> stackPointer < MAX_STACK_SIZE) {
        stack -> stackValue[stack -> stackPointer++] = pushedValue;
    }
    else {
        fprintf(stderr, "Character Stack full, can't push %g\n", pushedValue);
        exit(-1);
    }
}


char popChar(struct CharStack stack){
    if (stack.stackPointer > 0){
        return stack.stackValue[--stack.stackPointer];
    }
    else {
        fprintf(stderr, "Character Stack empty\n");
        exit(-1);
    }
}


void updateStacks(struct NumStack *operandStack, struct CharStack *operatorStack){
    double answer;
    char operation;
    char operatorStackPointer = operatorStack -> stackPointer;
    if (operatorStackPointer > 0){
        while((operation = popChar(*operatorStack)) != 'OPENING_PARENTHESIS'){
            double secondOperand = popNum(*operandStack);
            double firstOperand = popNum(*operandStack);
            switch(operation){
                case '+':
                    answer = add(firstOperand, secondOperand);
                    break;
                case '-':
                    answer = subtract(firstOperand, secondOperand);
                    break;
                case '*':
                    answer = multiply(firstOperand, secondOperand);
                    break;
                case '/':
                    answer = divide(firstOperand, secondOperand);
                    break;
            }
            pushNum(*operandStack, answer);
        }
    }
}

solveArithmeticEquation.c

Code:

#include <stdlib.h>#include "headerfile.h"

#define CLOSING_PARENTHESIS )

void convertToPostfix(char *infix){
    char token;
    while(token = getToken(*infix) != '\0'){
            if(token == isdigit(token)){
                pushNum(&operandStack, atoi(token));
            }
            else if(token != isdigit(token)){
                pushChar(operatorStack, token);
            }
            else if(token == 'CLOSING_PARENTHESIS'){
                updateStacks(&operandStack, &operatorStack);
            }
    }
}

mathUtilities.c

Code:

double add(double firstOperand, double secondOperand){    return firstOperand + secondOperand;
}


double subtract(double firstOperand, double secondOperand){
    return firstOperand - secondOperand;
}


double multiply(double firstOperand, double secondOperand){
    return firstOperand * secondOperand;
}


double divide(double firstOperand, double secondOperand){
    return firstOperand / secondOperand;
}

headerFile.h

Code:

#define MAX_STACK_SIZE 100

void printCharacterArray(char*);
char* getKeyboardInput(void);
char getToken(char **);


void pushNum(struct NumStack, double);
double popNum(struct NumStack);
void pushChar(struct CharStack , char);
char popChar(struct CharStack);


double add(double, double);
double subtract(double, double);
double multiply(double, double);
double divide(double, double);
void updateStacks(struct NumStack *, struct CharStack *);


struct NumStack{
    double stackValue[MAX_STACK_SIZE];
    int stackPointer;
};


struct CharStack{
    char stackValue[MAX_STACK_SIZE];
    int stackPointer;
};


extern struct NumStack operandStack;
extern struct CharStack operatorStack;

EDIT: Error is on line 9 in the solveArithmeticEquation.c

Compiler is complaining of "type of formal parameter 1 is incomplete"

What I did do to make it work is by putting this all in one file and then it seems fine. So what seems to be the problem? I have genuinely run out of solutions.

So in other words, if I define NumStackTEST and pushNumTEST in solveArithmeticEquations file instead of the stackUtilities file and then do this for line 9:

pushNumTEST(&operandStackTEST, atoi(token));

Then it works. But thats not good enough - I need it in separate files.