From fa1e8610f8182d1d1f20315682c7e31bca7ed2a3 Mon Sep 17 00:00:00 2001
From: Aadhavan Srinivasan <aadhavan@twomorecents.org>
Date: Fri, 14 Apr 2023 15:30:51 -0500
Subject: [PATCH] Fixed bug with manipulation of the message string, by
 creating a copy of the string parameter

---
 message_helpers.c | 28 ++++++++++++++++++----------
 1 file changed, 18 insertions(+), 10 deletions(-)

diff --git a/message_helpers.c b/message_helpers.c
index 1c87f3b..edcf33f 100644
--- a/message_helpers.c
+++ b/message_helpers.c
@@ -25,26 +25,34 @@ char* fetch_from_string(char* message, char* indicator) {
 }
 
 char* fetch_message_string(char* message) {
-	int num_of_terminators;
 
-	char* start = strstr(message,"START_OF_MESSAGE");
+	char* message_copy = malloc(strlen(message));
+	strcpy(message_copy,message);
+
+	int num_of_terminators = 0;
+	int start_index = 0;
+	int end_index = 0;
+	int message_length = 0;
+
+
+	char* start = strstr(message_copy,"START_OF_MESSAGE");
 	if (start == NULL) {
 		return NULL;
 	}
-	int start_index = start - message;
+	start_index = start - message_copy;
 	start_index += strlen("START_OF_MESSAGE");
 
-	while (*(message + start_index) == '\n' || *(message + start_index) == '\r') {
+	while (*(message_copy + start_index) == '\n' || *(message_copy + start_index) == '\r') {
 		start_index++;
 	}
 	
-	char* end = strstr(message,"END_OF_MESSAGE");
+	char* end = strstr(message_copy,"END_OF_MESSAGE");
 	if (end == NULL) {
 		return NULL;
 	}
-	int end_index = end - message;
+	end_index = end - message_copy;
 
-	if (*(message + end_index-2) = '\r') {
+	if (*(message_copy + end_index-2) == '\r') {
 		num_of_terminators = 2;
 	} else {
 		num_of_terminators = 1;
@@ -52,15 +60,15 @@ char* fetch_message_string(char* message) {
 
 	end_index -= num_of_terminators;
 
-	int message_length = end_index - start_index;
+	message_length = end_index - start_index;
 	char* message_string = malloc(message_length + 2);
 
-	printf("Message length is %d\n",message_length);
+	printf("Message goes from %d to %d\n",start_index,end_index);
 
 	for (int i=0; i<message_length; i++) { /* The reason the upper-bound is message_length-1 is because the last 
 						character is a new-line, which the user would not have typed. */
 
-		*(message_string + i) = *(message + start_index + i);
+		*(message_string + i) = *(message_copy + start_index + i);
 		printf("%c",*(message_string + i));
 	}