vendor-info/vendorInfo.c

/* 
 * Win (Thanawin Pattanaphol) 
 * vendorInfo.c
 * 8th August 2024
*/

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

#define MAX_VENDORS 20
#define MAX_FILENAME_LENGTH 4096

int read_input(char str[], int n);

struct vendor_item 
{
	char vendor_name[20];
	char merchandise[15];
	int inventory_count;
	int item_price_baht;	
} vendors[MAX_VENDORS];

int main() 
{
	char file_name[MAX_FILENAME_LENGTH];
	read_input(file_name, MAX_FILENAME_LENGTH);
	
	FILE *fp;
	if ((fp = fopen(file_name, "r")) == NULL) 
	{
		printf("%s cannot be opened.\n", file_name);
		exit(EXIT_FAILURE);
	}

	// calculate file size
	fseek(fp, 0, SEEK_END);
	unsigned long file_size = ftell(fp);
	fseek(fp, 0, SEEK_SET);

	// read file to buffer
	char *file_buffer = (char *) malloc(file_size);
	int index = 0;

	while (fgets(file_buffer, 50, fp) != NULL)
	{
		char *token = strtok(file_buffer, " ");
		strcpy(vendors[index].vendor_name, token); 
		
		token = strtok(NULL, " ");
		strcpy(vendors[index].merchandise, token); 
				
		token = strtok(NULL, " ");
		vendors[index].inventory_count = atoi(token);
				
		token = strtok(NULL, " ");
		vendors[index].item_price_baht = atoi(token);
				
		index++; 
	}

	for (int i = 0; i < MAX_VENDORS; i++) 
	{
		printf("%d | %s %s %d %d\n", i, vendors[i].vendor_name, vendors[i].merchandise, vendors[i].inventory_count, vendors[i].item_price_baht);
	}
	
	fclose(fp);
	free(file_buffer);
	return 0;
};

int read_input(char str[], int n) 
{
	int ch, i = 0;

	while ((ch = getchar()) != '\n') 
	{
		if (i < n) 
		{
			str[i++] = ch;
		}
	}

	str[i] = '\0';
	return i;
}