fix: check for existing string before mkstr

README

@@ -15,22 +15,22 @@ TECHNICALS
         * data structure that represents a node of the tree
     struct nod *mknod(struct nod *prnt)
         * create a child node below given parent node 
-        * returns: pointer to said node or NULL if fails
+        * returns: pointer to said node or NULL if function fails
     int mkstr(struct nod *rot, char *str)
         * fit string into tree if it does not already exist
         * warning: string has to be null-byte terminated 
-        * returns: the assigned ID of the string or -1 if fails
+        * returns: the assigned ID of the string, 0 if string 
+            is already inside tree, or -1 if function fails
     int gentree(struct nod *rot, char *strs)
         * generate tree from character seperated strings
         * warning: seperation character is '\n'
-        * returns: 0 if ok or -1 if fails
+        * returns: 0 if ok or -1 if function fails
     int streecmp(struct nod *rot, char *str) 
         * traverse tree and search for str
         * returns: id of string or 0 if there is no match
 
 TODO
 
-    * Detect strings which are already inside the tree
     * Memory leaks
     * Alloc/free functions
     * NULL checking

streecmp.c

@@ -39,6 +39,10 @@ struct nod *mknod(struct nod *nod, int loc) {
 int mkstr(struct nod *nod, char *str) {
     struct nod *target = nod->pool[*str];
     if (target != NULL) {
+        if (*str == '\0') {
+            return 0;
+        }
+
         return mkstr(target, str+1);
     }
 

test.c

@@ -136,14 +136,15 @@ int main(void) {
 
     int cnt = 1;
     for (char *tok = strtok(strs_cpy, "\n"); tok != NULL; tok
-            = strtok(NULL, "\n"), cnt++) {
+            = strtok(NULL, "\n")) {
         int found = streecmp(rot, tok);
         if (found == cnt) {
-            fprintf(stdout, "[+][%d\t] Success: could find"
-                    " '%s' in tree\n", cnt, tok);
+            fprintf(stdout, "[+][%d/%d] Success: could find"
+                    " '%s' in tree\n", cnt, found, tok);
+            cnt++;
         } else {
-            fprintf(stderr, "[-][%d\t] Error: could not find"
-                    " '%s' in tree\n", cnt, tok);
+            fprintf(stderr, "[-][%d/%d] Error: could not find"
+                    " '%s' in tree\n", cnt, found, tok);
         }
     }