Modified structs to typedef, documented all functions

vendorInfo.c

@@ -1,8 +1,8 @@
 /* 
  * vendorInfo.c
  *
- * Program that 
+ * SEN-102 Intro to Programming - Pre-Assessment
- *
+ * Program that simulates a market containing vendors.
  *
  *    Created by Win (Thanawin Pattanaphol), 28th August 2024
  */
@@ -16,55 +16,58 @@
 #define MAX_FILENAME_LENGTH 4096
 
 /* STRUCTURES */
-struct vendor
+typedef struct vendor
 {
 	char vendor_name[20];
 	char merchandise[15];
 	int inventory_count;
 	int item_price_baht;
 	int revenue;	
-	int duplicate; 
+	int duplicate;
-} vendors[MAX_VENDORS];
+} vendor;
 
-struct search_r
+// Return type for search function
+typedef struct search_r
 {
 	int status;
 	int item_id;
-};
+} search_r;
 
-struct purchase_r
+// Return type for purchase function 
+typedef struct purchase_r
 {
 	int status;
 	char vendor_name[20];
 	int price_owe_baht; 
-}; 
+} purchase_r; 
+
+vendor vendors[MAX_VENDORS];
 
 /* FUNCTION DECLARATION */
-void reset_output();
+int getstr(char str[], size_t n);
-int read_input(char str[], size_t n);
 char *strnlower(char *s, size_t n);
 
-struct search_r search
+search_r search
 (
 	char query[], 
-	struct vendor vendors[MAX_VENDORS], 
+	vendor vendors[MAX_VENDORS], 
 	int total_vendors
 );
 		   
-struct purchase_r purchase
+purchase_r purchase
 (
 	int item_id, 
 	int amount, 
-	struct vendor vendors[MAX_VENDORS]
+	vendor vendors[MAX_VENDORS]
 );
 
-int check_vendors(struct vendor vendors[MAX_VENDORS], int total_vendors);
+int check_vendors(vendor vendors[MAX_VENDORS], int total_vendors);
 
-int main() 
+int main()
-{
+{	
 	char file_name[MAX_FILENAME_LENGTH];
 	printf("Enter name of input file: ");
-	read_input(file_name, MAX_FILENAME_LENGTH);
+	getstr(file_name, MAX_FILENAME_LENGTH);
 	
 	FILE *fp;
 	if ((fp = fopen(file_name, "r")) == NULL) 
@@ -73,15 +76,16 @@ int main()
 		exit(EXIT_FAILURE);
 	}
 
-	// calculate file size
+	// Calculate the file size
 	fseek(fp, 0, SEEK_END);
 	unsigned long file_size = ftell(fp);
 	fseek(fp, 0, SEEK_SET);
 
-	// read file to buffer
+	// Dynamically allocate buffer for file content
 	char *file_buffer = (char *) malloc(file_size);
 	int index = 0;
 
+	// Reading the file with fgets and formatting them using strtok
 	while ((fgets(file_buffer, 50, fp) != NULL) && (index <= MAX_VENDORS - 1))
 	{
 		char *token = strtok(file_buffer, " ");
@@ -102,12 +106,20 @@ int main()
 	int total_vendors = index;
 	printf("\n>>> Read %d vendors from file %s\n", total_vendors, file_name);
 
-	// print out each vendor's info
+	// Print out each vendor's info - excluding duplicates. 
 	for (int i = 0; i <= (total_vendors - 1); i++) 
-	{	
+	{
+		/*
+		  This is similar to a linear search algorithm
+		  i = the current item
+		  j = the item next to i
+
+		  i is being compared to j:
+		      - if i == j then mark both i and j as duplicates
+		      - if not, move on to the next two items
+	    */
 		for (int j = i + 1; j < total_vendors; j++)
 		{
-		
 			if ((strcmp(vendors[i].merchandise, vendors[j].merchandise)) == 0) 
 			{
 				vendors[i].duplicate = 1;
@@ -139,8 +151,7 @@ int main()
 		} 
 		else
 		{
-			printf("\033[0;31mDuplicate record detected!\n");
+			printf("\e[31m%s\e[m\n", "Duplicate record detected!");   
-			reset_output();
 		}
 	}
 	
@@ -148,7 +159,6 @@ int main()
 
 	while (1) 
 	{
-		// CHECK IF ALL MERCHANDISE ARE EMPTY
 		if(check_vendors(vendors, total_vendors) == 0)
 		{
 			break;	
@@ -156,9 +166,12 @@ int main()
 	
 		char user_query[100];
 		printf("What do you want to buy? (DONE to end) ");
-		read_input(user_query, 100);
+		getstr(user_query, 100);
 
-		if (strcmp(user_query, "DONE") == 0) 
+		if (
+		    (strcmp(user_query, "DONE") == 0) ||
+		    (strcmp(user_query, "done") == 0)
+		) 
 		{
 			break;
 		}
@@ -179,12 +192,15 @@ int main()
 				char input[10];
 
 				printf("How many do you want to buy? ");
-				read_input(input, 10);
+				getstr(input, 10);
 
+				// If a character of a string was sent, the return value would always be 0
+				// If a negative number was sent, the return value will always be negative.
+				
 				if(atoi(input) > 0) 
 				{
 					int item_amount = atoi(input);
-					struct purchase_r response = purchase(item.item_id, item_amount, vendors);
+					purchase_r response = purchase(item.item_id, item_amount, vendors);
 
 					if (response.status == 0)
 					{
@@ -195,28 +211,33 @@ int main()
 					}
 					else
 					{
-						printf("\033[0;31mSorry -- %s does not have enough items available\n",
+						printf("\e[31m%s -- %s %s\e[m\n",
-							response.vendor_name
+							   "Sorry",
+							   response.vendor_name,
+							   "does not have enough items available"
 						);
-						reset_output();
 					}
 				}
 				else 
 				{
-					printf("\033[0;31mYou must enter a positive whole number for the number of items\n");	
+					printf("\e[31m%s\e[m\n",
-					reset_output();	
+						   "You must enter a positive whole number for the number of items"
+					);                      	
 				}
 
 			}
 			else if (item.status == 2)
 			{
-				printf("\033[0;31mThis item has duplicate records, please choose another item\n");
+				printf("\e[31m%s\e[m\n",
-				reset_output();
+					   "This item has duplicate records, please choose another item"
+				);
 			}
 			else
 			{
-				printf("\033[0;31mNo vendor in this market sells %s\n", user_query);
+				printf("\e[31m%s %s\e[m\n",
-				reset_output();
+					   "No vendor in this market sells",
+					   user_query
+			    );
 			}
 		}
 	}
@@ -248,22 +269,16 @@ int main()
 	return 0;
 };
 
-/* 
-	Output color reset
-*/
-void reset_output()
-{
-	printf("\033[0m");
-};
-
 /*
-	read_input: Custom read input function
+	getstr: Custom read input function
-	str = string itself
-	n = max amount of characters that the function is able to read into buffer
 
-	reads one character at a time into buffer and adds a null terminator when finish reading
+	Parameters: 
+	    - str = string itself
+	    - n = max amount of characters that the function is able to read into buffer
+
+	Reads one character at a time into buffer and adds a null terminator when finish reading
 */
-int read_input(char str[], size_t n) 
+int getstr(char str[], size_t n) 
 {
 	int ch, i = 0;
 
@@ -285,7 +300,9 @@ int read_input(char str[], size_t n)
 	Parameters:
 		- s: String
 		- n: Length of string
-	
+
+    Return values:
+	    - (char *): Lowercased version of the string. 
 */
 char *strnlower(char *s, size_t n)
 {
@@ -299,17 +316,18 @@ char *strnlower(char *s, size_t n)
 	Search function
 
 	Parameters:
-		- query: search query
+		- (string) query: search query
-		- vendors: the vendor table
+		- (vendor) vendors: the vendor table
-		- total_vendors: the amount of vendors
+		- (int) total_vendors: the amount of vendors
 
 	Return values:
-		- i: Item Number
+	    (search_r) response:
-		- 0: No results found
+	    - status: 0 (Found item)
+		- status: 1 (No results)
+		- status: 2 (Found duplicate item)
 */
 
-/* TO-DO IMPLEMENT RESPONSE STRUCT */
+search_r search(char query[], vendor vendors[MAX_VENDORS], int total_vendors)
-struct search_r search(char query[], struct vendor vendors[MAX_VENDORS], int total_vendors)
 {
 	int i; 
 	for (i = 0; i < total_vendors; i++)
@@ -319,7 +337,7 @@ struct search_r search(char query[], struct vendor vendors[MAX_VENDORS], int tot
 		{
 			if (vendors[i].duplicate == 0)
 			{
-				struct search_r response;
+				search_r response;
 				response.status = 0;
 				response.item_id = i;
 				
@@ -328,7 +346,7 @@ struct search_r search(char query[], struct vendor vendors[MAX_VENDORS], int tot
 			}
 			else
 			{	
-				struct search_r response;
+				search_r response;
 				response.status = 2;
 				return (response);
 			}
@@ -337,7 +355,7 @@ struct search_r search(char query[], struct vendor vendors[MAX_VENDORS], int tot
 
 	if (i == total_vendors)
 	{
-		struct search_r response;
+		search_r response;
 		response.status = 1;
 		response.item_id = 0;
 		return (response);
@@ -345,7 +363,7 @@ struct search_r search(char query[], struct vendor vendors[MAX_VENDORS], int tot
 };
 
 /* 
-	Purchase function
+	purchase: Purchase function
 
 	Parameters:
 		- item_id: The item id that the user is purchasing
@@ -353,16 +371,19 @@ struct search_r search(char query[], struct vendor vendors[MAX_VENDORS], int tot
 		- vendors: vendor table
 
 	Return values:
-		- 
+	    (purchase_r) response:
+	    - status: 0 (Purchase successful)
+		- status: 1 (Vendor does not have enough items)
 */
-struct purchase_r purchase(int item_id, int amount, struct vendor vendors[MAX_VENDORS])
+
+purchase_r purchase(int item_id, int amount, vendor vendors[MAX_VENDORS])
 {
 	if(amount <= vendors[item_id].inventory_count)
 	{
 		// Decrease vendor inventory
 		vendors[item_id].inventory_count = vendors[item_id].inventory_count - amount;
 
-		struct purchase_r response;
+		purchase_r response;
 
 		response.status = 0;
 		strcpy(response.vendor_name, vendors[item_id].vendor_name);
@@ -370,11 +391,11 @@ struct purchase_r purchase(int item_id, int amount, struct vendor vendors[MAX_VE
 
 		vendors[item_id].revenue = vendors[item_id].item_price_baht * amount; 
 		
-		return (response);
+		return response;
 	}
 	else
 	{
-		struct purchase_r response; 
+		purchase_r response; 
 		response.status = 1;
 		strcpy(response.vendor_name, vendors[item_id].vendor_name);
 		
@@ -383,23 +404,29 @@ struct purchase_r purchase(int item_id, int amount, struct vendor vendors[MAX_VE
 };
 
 /* 
-	Check function
+	check_vendors: Custom function to check if all vendors are empty.
 
 	Parameters:
+	    - vendors[MAX_VENDORS]: (vendor) All of the vendors.
+		- total_vendors: (integer) Total vendors in market.
+
+	Return values:
+	    - (int) 0: All vendors are empty.
+		- (int) 1: There are still items left. 
 */
-int check_vendors(struct vendor vendors[MAX_VENDORS], int total_vendors)
+
+int check_vendors(vendor vendors[MAX_VENDORS], int total_vendors)
 {
 	int i;
 	for (i = 0; i < total_vendors; i++)
-	{	
+	{
-		// If there are any items left
+		// Condition: Vendors that are not empty (Check if not marked as duplicates) 
 		if (vendors[i].inventory_count != 0 && vendors[i].duplicate == 0)
 		{
 			return 1;
 		}
 	}
 
-	// There aren't any
 	if (i == total_vendors)
 	{
 		return 0;

vendorsmall.data

@@ -1,4 +1,4 @@
 Win phone 1 50
-Win books 1 70
+Peter books 1 70
-Win books 5 100
+Amy teeshirts 5 100
 Deez computers 5 80