Why Pset6 check cat.exe and non-existant file going wrong?

Question

:( Requesting cat.exe returns error code 501 \ expected output, not an exit code of 0 :( Requesting non-existant file returns error code 404 \ expected output, not an exit code of 0

code for lookup and parse-

/**
 * Returns MIME type for supported extensions, else NULL.
 */
const char* lookup(const char* path)
{
    char* ext = strstr(path,".");

     if (strcasecmp(ext,".css") == 0)
     {
        return "text/css";
     }
     else if (strcasecmp(ext,".html") == 0)
     {
        return "text/html";
     }
     else if (strcasecmp(ext,".gif") == 0)
     {
        return "image/gif";
     }
     else if (strcasecmp(ext,".ico") == 0)
     {
        return "image/x-icon";
     }
     else if (strcasecmp(ext,".jpg") == 0)
     {
        return "image/jpeg";
     }
     else if (strcasecmp(ext,".js") == 0)
     {
        return "text/javascript";
     }
     else if (strcasecmp(ext,".php") == 0)
     {
        return "text/x-php";
     }
     else if (strcasecmp(ext,".png") == 0)
     {
        return "image/png";
     }
     else
     return NULL;
}

/**
 * Parses a request-line, storing its absolute-path at abs_path 
 * and its query string at query, both of which are assumed
 * to be at least of length LimitRequestLine + 1.
 */
bool parse(const char* line, char* abs_path, char* query)
{
    if (strstr(line,"HTTP/1.1") == NULL)
    {
        error(505);
        return false;
    }

    int blnk_count = 0;
    int x = 0;
    while (line[x] != '\0')
    {
        if (line[x] == '"')
        {
            error(400);
            return false;
        }
        if (line[x] == ' ')
        {
            blnk_count++;
        }
        x++;
    }
    if (blnk_count != 2)
    {
        error(400);
        return false;
    }
    if (strncmp(line,"GET ",4) != 0)
    {
        error(405);
        return false;
    }
    if (strncmp(line,"GET /",5) != 0)
    {
        error(501);
        return false;
    }
    char* ptr1 = strchr(line,'/');
    char* ptr2 = strchr(line,'?');

    if (ptr2 == NULL)
    {
        ptr2 = strrchr(line,' ');
    }

    char path[ptr2 - ptr1 + 1];
    int n = ptr2 - ptr1;

    for (int i=0;i<n;i++)
    {
        path[i]=*ptr1;
        ptr1++;
    }
    path[n]='\0';

    strcpy(abs_path,path);
    free(path);

    if (*ptr1 == '?')
    {
        if (*(ptr1+1) ==' ')
        {
            query = "\0";
        }
        else
        {
            ptr1 = ptr1+1;
            ptr2 = (strchr(line,' '));
            char temp_query[ptr2 - ptr1 + 1];
            int m = ptr2 - ptr1;

            for (int i=0;i<n;i++)
            {
                temp_query[i] = *ptr1;
                ptr1++;
            }
            temp_query[m]='\0';
            strcpy(query,temp_query);
            free(temp_query);
        }
    }
    else if(*ptr1 == ' ')
    {
        query = "\0";
    }

    return true;
}

Answer 1

First suggest you send a request to server from browser or curl. You will discover that server seg faults. (That's what this \ expected output, not an exit code of 0 feedback from check50 indicates).

Next, in Week4 > Section > Dynamic Memory Allocation review the "Three Golden Rules" of memory allocation, around 8:45.

(1) Every block of memory that you malloc() must subsequently be free() d. (2) Only memory that you malloc() should be free() d. (3) Do not free() a block of memory more than once.

Then review your program for "violations" of the second rule. I see two places.