Help with cs50 server

Question

EDIT Done with server.c and pset6! Thanks to everyone that helped me! EDIT

I really need some help understanding what my issue is with server.c. I have been working on this for a few days and cannot resolve my problems. When I run check50 I get these errors:

:) server.c exists

:) server compiles

:( Requesting cat.jpg returns 200, image/jpeg, and correct image

:( Requesting cat.html returns 200, text/html, and correct file

:( Requesting cat2.HTML returns 200, text/html, and correct file

:( Requesting cat3.HtMl returns 200, text/html, and correct file
   \ expected an exit code of 0, not standard error of "======= Backtrace: =========\n======= M..."

:( Requesting cat.gif returns 200, image/gif, and correct file

:( Requesting favicon.ico returns 200, image/x-icon, and correct file

:) Requesting test.css returns 200, text/css, and correct file

:( Requesting test.js returns 200, text/javascript, and correct file
   \ expected an exit code of 0, not standard error of "======= Backtrace: =========\n======= M..."

:) Requesting hello.php returns 200, text/html, and correct output

:) Requesting hello.php? returns 200, text/html, and correct output

:( Requesting hello.php?name=Alice returns 200, text/html, and correct 
output
   \ expected output, but not "X-Powered-By: PHP/5.5.7\r\nContent-type..."

:) Requesting /test redirects to /test/

:( Requesting /test/ outputs /test/index.html

:( Requesting directory containing index.php outputs index.php
   \ expected output, but not "HTTP/1.1 200 OK\r\nContent-Type: text/h..."

:( Requesting two files in a row (cat.html then cat.jpg) succeeds

Here is my code:

Lookup:

//extension variable
char* extension = strrchr(path, '.');

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

Parse:

//ensure HTTP method is GET
if (line[0] != 'G' || line[1] != 'E' || line[2] != 'T' || line[3] != ' ')
{
    error(405);
    return false;
}

//ensure line only has two spaces
int spaces = 0;
for (int i = 0, j = strlen(line); i < j; i++)
{
    if (line[i] == ' ')
    {
        spaces++;
    }

    if (spaces > 2)
    {
        error(400);
        return false; 
    }
}

//ensure request target starts with /
char* RT = strchr(line, ' ');
if (RT[1] != '/')
{
    error(501);
    return false;
}

//throw an error at user if RT has "
for (int i = 0; RT[i + 1] != ' '; i++)
{
    if (RT[i + 1] == '"')
    {
        error(400);
        return false;
    }
}

//iterate over line and store request target in abs_path
int count = 1;
while (RT[count] != ' ' && RT[count] != '?')
{
    abs_path[count - 1] = RT[count];
    abs_path[count] = '\0';
    count++;
}

//check if request target has a query
int qcount = 0;
if (RT[count] == '?')
{
    if (RT[count + 1] == ' ')
    {
        query[0] = '\0';
        count++;
    }
    else
    {
        count++;
        while (RT[count] != ' ')
        {
            query[qcount] = RT[count];
            query[qcount + 1] = '\0';
            count++;
        }
    }

}

//ensure HTTP version is version 1.1
if (RT[count + 1] != 'H' || RT[count + 2] != 'T' || RT[count + 3] != 'T' || RT[count + 4] != 'P' || RT[count + 5] != '/' || RT[count + 6] != '1' || RT[count + 7] != '.' || RT[count + 8] != '1')
{
    error(505);
    return false;
}

return true;

Load:

if (file == NULL)
{
    return false;
}

//create buffer
char* buffer = malloc(sizeof(file));
int c;

//keep count of bytes
int count = 0;

//iterate over file storing in buffer
while ((c = fgetc(file)) != EOF)
{
    buffer[count] = (char) c;
    count++;
}

//put buffer in content and count into length
*content = buffer;
*length = count;

return true;

Indexes:

//variables for index
char* html = "index.html";
char* php = "index.php";

//create a copy of path
char* copy = malloc(1000);

for (int i = 0, j = strlen(path); i < j; i++)
{
    copy[i] = path[i];
}

if (copy[strlen(copy - 1)] != '/')
{
    strcat(copy, "/");
}

//concatenate copy with index.html and index.php
char* html_index = strcat(copy, html);
char* php_index = strcat(copy, php);

//check if index.html or index.php actually exists
if (access(html_index, F_OK) == 0)
{
    free(copy);
    return html_index;
}
else if (access(php_index, F_OK) == 0)
{
    free(copy);
    return php_index;
}
else
{
    free(copy);
    return NULL;
}

Any help would be appreciated! Thanks!

Answer 1

This line if (copy[strlen(copy - 1)] != '/') might be causing problems in your indexes function. It looks wrong in any case. Look carefully at your parentheses.

Your variable copy is not properly null-terminated, so there's no telling what the strcats will do. You might want to review the man page for calloc. [As an aside, the allocation of copy for 1000 bytes is very rando. You could get a more realistic approximation of the maximum length it will be. How about the length of path plus the length of index.html (the longer of the two) plus the pesky null-byte.]

Also, review the spec for indexes

given a /path/to/a/directory, returns /path/to/a/directory/index.php if index.php actually exists therein, or /path/to/a/directory/index.html if index.html actually exists therein, or NULL.

Does your code do what the spec requires? Order is significant.