fix warnings and added more comments

assignment_2.c

@@ -16,11 +16,11 @@ Description: validate of x509 cert against DNS name
 
 // get column from csv
 char* getfield(char* line, int num){
-    char* tok;
+    char* column;
     char *newline = strtok(line, "\n");
-    for (tok = strtok(newline, ","); tok && *tok; tok = strtok(NULL, ",")){   
+    for (column = strtok(newline, ","); column && *column; column = strtok(NULL, ",")){   
         if (!--num)
-            return tok;
+            return column;
     }
     return NULL;
 }
@@ -189,18 +189,14 @@ int cmp_san(X509 *cert, char *url){
 }
 
 int validate_url(X509 *cert, char *url){
+    // validation process
     int time_result = cmp_time(cert);
-    int cn_result = cmp_cn(cert, &url);
+    int cn_result = cmp_cn(cert, url);
     int rsa_result = cmp_rsa_length(cert);
     int ca_result = cmp_ca(cert);
     int eku_result = cmp_key_usage(cert);
-    int san_result = cmp_san(cert, &url);
-    // printf("%i\n",time_result);
-    // printf("%i\n",cn_result);
-    // printf("%i\n",rsa_result);
-    // printf("%i\n",ca_result);
-    // printf("%i\n",eku_result);
-    // printf("%i\n",san_result);
+    int san_result = cmp_san(cert, url);
+
     int result;
     // only one fo SAN and CN should be 
     if (cn_result == 0){
@@ -214,7 +210,7 @@ int validate_url(X509 *cert, char *url){
     return 1;
 }
 
-int read_and_validate(const char *test_cert_example, const char *url){
+int read_and_validate(const char *test_cert_example, char *url){
     // const char test_cert_example[] = "cert-file2.pem";
     BIO *certificate_bio = NULL;
     X509 *cert = NULL;