Stefano - C-Web-Server

src/cache.c

@@ -9,19 +9,34 @@
  */
 struct cache_entry *alloc_entry(char *path, char *content_type, void *content, int content_length)
 {
-    ///////////////////
-    // IMPLEMENT ME! //
-    ///////////////////
+    struct cache_entry *new_cache_entry = malloc(sizeof *new_cache_entry);
+
+    // Deep copy
+    new_cache_entry->path = malloc(strlen(path) + 1);
+    strcpy(new_cache_entry->path, path);
+
+    new_cache_entry->content_type = malloc(strlen(content_type) + 1);
+    strcpy(new_cache_entry->content_type, content_type);
+
+    new_cache_entry->content_length = content_length;
+
+    new_cache_entry->content = malloc(content_length);
+    memcpy(new_cache_entry->content, content, content_length);
+
+    new_cache_entry->prev = new_cache_entry->next = NULL;
+
+    return new_cache_entry;
 }
 
 /**
  * Deallocate a cache entry
  */
 void free_entry(struct cache_entry *entry)
 {
-    ///////////////////
-    // IMPLEMENT ME! //
-    ///////////////////
+    free(entry->path);
+    free(entry->content_type);
+    free(entry->content);
+    free(entry);
 }
 
 /**
@@ -91,9 +106,14 @@ struct cache_entry *dllist_remove_tail(struct cache *cache)
  */
 struct cache *cache_create(int max_size, int hashsize)
 {
-    ///////////////////
-    // IMPLEMENT ME! //
-    ///////////////////
+    struct cache *cache = malloc(sizeof *cache);
+
+    cache->index = hashtable_create(hashsize, NULL);
+    cache->head = cache->tail = NULL;
+    cache->cur_size = 0;
+    cache->max_size = max_size;
+
+    return cache;
 }
 
 void cache_free(struct cache *cache)
@@ -122,17 +142,35 @@ void cache_free(struct cache *cache)
  */
 void cache_put(struct cache *cache, char *path, char *content_type, void *content, int content_length)
 {
-    ///////////////////
-    // IMPLEMENT ME! //
-    ///////////////////
+    struct cache_entry *entry = alloc_entry(path, content_type, content, content_length);
+
+    dllist_insert_head(cache, entry);
+
+    hashtable_put(cache->index, path, entry);
+
+    cache->cur_size++;
+
+    if (cache->cur_size > cache->max_size) {
+        struct cache_entry *removed_cache_entry = dllist_remove_tail(cache);
+        hashtable_delete(cache->index, removed_cache_entry->path);
+        free_entry(removed_cache_entry);
+        if (cache->cur_size != cache->max_size) {
+            cache->cur_size = cache->max_size;
+        }
+    }
 }
 
 /**
  * Retrieve an entry from the cache
  */
 struct cache_entry *cache_get(struct cache *cache, char *path)
 {
-    ///////////////////
-    // IMPLEMENT ME! //
-    ///////////////////
+    struct cache_entry *entry = hashtable_get(cache->index, path);
+
+    if (entry == NULL) {
+        return NULL;
+    }
+
+    dllist_move_to_head(cache, entry);
+    return entry;
 }

src/file.c

@@ -72,4 +72,4 @@ void file_free(struct file_data *filedata)
 {
     free(filedata->data);
     free(filedata);
-}
+}

src/server.c

@@ -52,12 +52,30 @@ int send_response(int fd, char *header, char *content_type, void *body, int cont
 {
     const int max_response_size = 262144;
     char response[max_response_size];
-
+
+    // Generate date
+    time_t rawtime;
+    struct tm *current_time;
+    time(&rawtime);
+    current_time = localtime(&rawtime);
+
     // Build HTTP response and store it in response
-
-    ///////////////////
-    // IMPLEMENT ME! //
-    ///////////////////
+    sprintf(response,
+            "%s\n"
+            "Date: %s" // Example: Wed Dec 20 13:05:11 PST 2017
+            "Connection: close\n"
+            "Content-Length: %d\n"
+            "Content-Type: %s\n"
+            "\n"
+            "%s",
+            header,
+            asctime(current_time),
+            content_length,
+            content_type,
+            body
+    );
+
+    int response_length = strlen(response);
 
     // Send it all!
     int rv = send(fd, response, response_length, 0);
@@ -76,16 +94,13 @@ int send_response(int fd, char *header, char *content_type, void *body, int cont
 void get_d20(int fd)
 {
     // Generate a random number between 1 and 20 inclusive
+    srand(time(NULL));
+    char random_number_string[20];
+    int random_number = rand() % 20;
+    sprintf(random_number_string, "%d", random_number);
 
-    ///////////////////
-    // IMPLEMENT ME! //
-    ///////////////////
-
     // Use send_response() to send it back as text/plain data
-
-    ///////////////////
-    // IMPLEMENT ME! //
-    ///////////////////
+    send_response(fd, "HTTP/1.1 200 OK", "text/plain", random_number_string, strlen(random_number_string));
 }
 
 /**
@@ -94,7 +109,7 @@ void get_d20(int fd)
 void resp_404(int fd)
 {
     char filepath[4096];
-    struct file_data *filedata; 
+    struct file_data *filedata;
     char *mime_type;
 
     // Fetch the 404.html file
@@ -119,9 +134,26 @@ void resp_404(int fd)
  */
 void get_file(int fd, struct cache *cache, char *request_path)
 {
-    ///////////////////
-    // IMPLEMENT ME! //
-    ///////////////////
+    char filepath[4096];
+    struct file_data *filedata;
+    char *mime_type;
+    struct cache_entry *cached_file = cache_get(cache, request_path);
+
+    if (cached_file != NULL) {
+        send_response(fd, "HTTP/1.1 200 OK", cached_file->content_type, cached_file->content, cached_file->content_length);
+    } else {
+        sprintf(filepath, "./serverroot%s", request_path);
+
+        mime_type = mime_type_get(filepath);
+
+        filedata = file_load(filepath);
+
+        send_response(fd, "HTTP/1.1 200 OK", mime_type, filedata->data, filedata->size);
+
+        cache_put(cache, request_path, mime_type, filedata->data, filedata->size);
+
+        file_free(filedata);
+    }
 }
 
 /**
@@ -144,6 +176,8 @@ void handle_http_request(int fd, struct cache *cache)
 {
     const int request_buffer_size = 65536; // 64K
     char request[request_buffer_size];
+    char method[200];
+    char path[8192];
 
     // Read request
     int bytes_recvd = recv(fd, request, request_buffer_size - 1, 0);
@@ -153,19 +187,22 @@ void handle_http_request(int fd, struct cache *cache)
         return;
     }
 
-
-    ///////////////////
-    // IMPLEMENT ME! //
-    ///////////////////
-
     // Read the three components of the first request line
-
+    sscanf(request, "%s %s", method, path);
+
     // If GET, handle the get endpoints
-
-    //    Check if it's /d20 and handle that special case
-    //    Otherwise serve the requested file by calling get_file()
-
-
+    if (strcmp(method, "GET") == 0) {
+        if (strcmp(path, "/d20") == 0) {
+            //    Check if it's /d20 and handle that special case
+            get_d20(fd);
+        } else if (path != NULL) {
+            //    Otherwise serve the requested file by calling get_file()
+            get_file(fd, cache, path);
+        } else {
+            resp_404(fd);
+        }
+    }
+
     // (Stretch) If POST, handle the post request
 }
 
@@ -187,7 +224,7 @@ int main(void)
         fprintf(stderr, "webserver: fatal error getting listening socket\n");
         exit(1);
     }
-
+    
     printf("webserver: waiting for connections on port %s...\n", PORT);
 
     // This is the main loop that accepts incoming connections and