14 files changed, 314 insertions, 80 deletions

diff --git a/Semestr 4/sieci/pracownia2/router/config.h b/Semestr 4/sieci/pracownia2/router/config.h
new file mode 100644
index 0000000..3537c03
--- /dev/null
+++ b/Semestr 4/sieci/pracownia2/router/config.h
@@ -0,0 +1,9 @@
+#ifndef CONFIG_H
+#define CONFIG_H
+
+#define SERVER_PORT 54321
+#define TURN_LEN_S 5
+#define TURN_LEN_MS (1000 * TURN_LEN_S)
+#define TURN_LEN_US (1000000 * TURN_LEN_S)
+
+#endif
\ No newline at end of file
diff --git a/Semestr 4/sieci/pracownia2/router/dist_vector.c b/Semestr 4/sieci/pracownia2/router/dist_vector.c
new file mode 100644
index 0000000..1e09bff
--- /dev/null
+++ b/Semestr 4/sieci/pracownia2/router/dist_vector.c
@@ -0,0 +1,8 @@
+#include "dist_vector.h"
+
+bool is_connected_directly(struct vector_item item) {
+  return (get_network_address(item.network).s_addr == 
+    get_network_address(item.via_ip).s_addr);
+}
+
+void update_distance_vector(list_t *distance_vector, struct vector_item new_item) {}
\ No newline at end of file
diff --git a/Semestr 4/sieci/pracownia2/router/dist_vector.h b/Semestr 4/sieci/pracownia2/router/dist_vector.h
new file mode 100644
index 0000000..cd1a995
--- /dev/null
+++ b/Semestr 4/sieci/pracownia2/router/dist_vector.h
@@ -0,0 +1,24 @@
+#ifndef DIST_VECTOR_H
+#define DIST_VECTOR_H
+
+#include "linked_list.h"
+#include "network_addr.h"
+
+/* Item of the distance vector. 
+ * If <<reachable>> is set to 0, then it means that the network is reachable.
+ * If <<reachable>> has positive value, then it indicates that the network was
+ * unreachable for <<reachable>> turns.
+ */
+struct vector_item {
+  struct network_addr network;
+  router_addr         via_ip;
+  uint8_t             reachable;
+};
+
+/* Returns true if given distance vector item is connected directly, false otherwise */
+bool is_connected_directly(struct vector_item item);
+
+/* Updates the distance vector. */
+void update_distance_vector(list_t *distance_vector, struct vector_item new_item);
+
+#endif
\ No newline at end of file
diff --git a/Semestr 4/sieci/pracownia2/router/linked_list.c b/Semestr 4/sieci/pracownia2/router/linked_list.c
new file mode 100644
index 0000000..b6b5225
--- /dev/null
+++ b/Semestr 4/sieci/pracownia2/router/linked_list.c
@@ -0,0 +1,58 @@
+#include "linked_list.h"
+#include <stdlib.h>
+#include <stdint.h>
+
+node_t *_next(node_t *node) {
+  return (node == NULL) ? NULL : node->next;
+}
+
+void _insert(node_t **head, void *data, size_t data_size) {
+  node_t *new_node = (node_t *)malloc(sizeof(node_t));
+  new_node->data = malloc(data_size);
+  for (int i = 0; i < data_size; i++)
+    *(uint8_t *)(new_node->data + i) = *(uint8_t *)(data + i);
+  
+  new_node->next = *head;
+  *head = new_node;
+}
+
+void _erase(node_t **head) {
+  node_t *next_node = _next(*head);
+  free((*head)->data);
+  free(*head);
+  *head = next_node;
+}
+
+void _free_list(node_t *head) {
+  if (head == NULL) return;
+  _free_list(head->next);
+  free(head->data);
+  free(head);
+}
+
+list_t create_list() {
+  list_t ret;
+  ret.head = NULL;
+  ret.it = NULL;
+  return ret;
+}
+
+void insert(list_t *list, void *data, size_t data_size) {
+  _insert(&list->head, data, data_size);
+}
+
+void erase(list_t *list) {
+  _erase(&list->head);
+}
+
+void iterate(list_t *list) {
+  list->it = _next(list->it);
+}
+
+void reset(list_t *list) {
+  list->it = list->head;
+}
+
+void free_list(list_t *list) {
+  _free_list(list->head);
+}
\ No newline at end of file
diff --git a/Semestr 4/sieci/pracownia2/router/linked_list.h b/Semestr 4/sieci/pracownia2/router/linked_list.h
new file mode 100644
index 0000000..f662dbe
--- /dev/null
+++ b/Semestr 4/sieci/pracownia2/router/linked_list.h
@@ -0,0 +1,38 @@
+#ifndef LINKED_LIST_H
+#define LINKED_LIST_H
+
+#include <stddef.h>
+
+typedef struct node {
+  void *data;
+  struct node *next;
+} node_t;
+
+
+typedef struct list_t {
+  node_t *head;
+  node_t *it;
+} list_t;
+
+/* Creates an empty list */
+list_t create_list();
+
+/* Insert a new node in the begining of a list. */
+void insert(list_t *list, void *data, size_t data_size);
+
+/* Erases first node from the list. */
+void erase(list_t *list);
+
+/* Moves iterator one step. */
+void iterate(list_t *list);
+
+/* Resets the iterator. 
+ * Should execute the function after if you want to itarate unless you didnt insert or erase anything from the list. 
+ */
+void reset(list_t *list);
+
+/* Deletes the whole list. */
+void free_list(list_t *list);
+
+
+#endif
\ No newline at end of file
diff --git a/Semestr 4/sieci/pracownia2/router/network_addr.c b/Semestr 4/sieci/pracownia2/router/network_addr.c
new file mode 100644
index 0000000..a65f48c
--- /dev/null
+++ b/Semestr 4/sieci/pracownia2/router/network_addr.c
@@ -0,0 +1,50 @@
+#include "network_addr.h"
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+struct in_addr _get_broadcast_address(struct in_addr addr, uint16_t netmask) {
+  struct in_addr result = addr;
+  /* bitshift by more than 31 is UB */
+  if (netmask < 32) {
+    result.s_addr |= ~((1<<netmask) - 1);
+  }
+  return result;
+}
+
+struct in_addr _get_network_address(struct in_addr addr, uint16_t netmask) {
+  struct in_addr result = addr;
+  if (netmask == 0) {
+    addr.s_addr = 0;
+  }
+  else {
+    result.s_addr &= ~((1 << (32 - netmask)) - 1);
+  }
+  return result;
+}
+
+struct in_addr get_broadcast_address(struct network_addr na) {
+  return _get_broadcast_address(na.addr, na.netmask);
+}
+
+struct in_addr get_network_address(struct network_addr na) {
+  return _get_network_address(na.addr, na.netmask);
+}
+
+void pretty_print(struct network_addr na) {
+  char ip_addr[20];
+  inet_ntop(AF_INET, &na.addr, ip_addr, sizeof(ip_addr));
+  printf("%s/%d distance %d\n", ip_addr, na.netmask, na.distance);
+}
+
+struct network_addr stora(char *str) {
+  struct network_addr  result;
+  char                addr[20];
+  size_t              ip_preffix = strcspn(str, "/");
+  
+  strncpy(addr, str, strlen(str));
+  addr[ip_preffix] = 0;
+  inet_pton(AF_INET, addr, &(result.addr));
+  result.netmask = atoi(str + ip_preffix + 1);
+  return result;
+}
diff --git a/Semestr 4/sieci/pracownia2/router/network_addr.h b/Semestr 4/sieci/pracownia2/router/network_addr.h
new file mode 100644
index 0000000..777406a
--- /dev/null
+++ b/Semestr 4/sieci/pracownia2/router/network_addr.h
@@ -0,0 +1,43 @@
+#ifndef ROUTER_ADDR_H
+#define ROUTER_ADDR_H
+
+#include <arpa/inet.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#define INFINITY_DIST 128
+
+/* Network address and sitance */
+struct network_addr {
+  struct in_addr  addr;
+  uint16_t        distance;
+  uint8_t         netmask;
+};
+
+typedef struct network_addr router_addr;
+
+/* Item of the distance vector. 
+ * If <<reachable>> is set to 0, then it means that the network is reachable.
+ * If <<reachable>> has positive value, then it indicates that the network was
+ * unreachable for <<reachable>> turns.
+ */
+struct vector_item {
+  struct network_addr network;
+  struct in_addr      via_ip;
+  uint8_t             reachable;
+};
+
+/* Returns broadcast address of a given network. */
+struct in_addr get_broadcast_address(struct network_addr na);
+
+/* Returns network address of a given network */
+struct in_addr get_network_address(struct network_addr na);
+
+/* Prints network_addr via stdio. */
+void pretty_print(struct network_addr na);
+
+/* Converts string of ip in CIDR notation with a netmask to network_addr. */
+struct network_addr stora(char *str);
+
+
+#endif
\ No newline at end of file
diff --git a/Semestr 4/sieci/pracownia2/router/router.c b/Semestr 4/sieci/pracownia2/router/router.c
index f68a6a3..031ead8 100644
--- a/Semestr 4/sieci/pracownia2/router/router.c
+++ b/Semestr 4/sieci/pracownia2/router/router.c
@@ -7,18 +7,13 @@
 #include <stdint.h>
 #include <stdlib.h>
 #include <unistd.h>
-#include "router_addr.h"
+#include "network_addr.h"
 #include "utils.h"
 
-#define SERVER_PORT 54321
-#define TURN_LEN_S 5
-#define TURN_LEN_MS (1000 * TURN_LEN_S)
-#define TURN_LEN_US (1000000 * TURN_LEN_S)
-
-uint16_t read_configuration(struct router_addr** networks) {
+uint16_t read_configuration(struct network_addr** networks) {
   uint16_t n;
   scanf("%hd", &n);
-  *networks = malloc(n * sizeof(struct router_addr));
+  *networks = malloc(n * sizeof(struct network_addr));
   for (int i = 0; i < n; i++) {
     char addr[20];
     char _dist[10];
@@ -30,7 +25,7 @@ uint16_t read_configuration(struct router_addr** networks) {
   return n;
 }
 
-void listen_for_routers(int sockfd, int timeout, int networks_number, struct router_addr *netowrks) {
+void listen_for_routers(int sockfd, int timeout, int networks_number, struct network_addr *netowrks) {
   printf("Listening for %dms.\n", timeout);
   while (poll_socket_modify_timeout(sockfd, &timeout)) {
     printf("Poll returned, remaining timeout: %dms.\n", timeout);
@@ -40,12 +35,6 @@ void listen_for_routers(int sockfd, int timeout, int networks_number, struct rou
 }
 
 int send_distance_vector(int sockfd, struct in_addr network) {
-  struct sockaddr_in network_address;
-  bzero (&network_address, sizeof(network_address));
-  network_address.sin_family       = AF_INET;
-  network_address.sin_port         = htons(SERVER_PORT);
-  network_address.sin_addr         = network;
-
   char* message = "Hello server! My name is S1\n";
   ssize_t message_len = strlen(message);
   int result;
@@ -53,12 +42,12 @@ int send_distance_vector(int sockfd, struct in_addr network) {
   char addr[20];
   inet_ntop(AF_INET, &network, addr, sizeof(addr));
   printf("Sending datagram to %s\n", addr);
-  if ((result = sendto(sockfd, message, message_len, 0, (struct sockaddr*) &network_address, sizeof(network_address))) != message_len) {
+  if ((result = send_message(sockfd, message, message_len, network)) != message_len) {
     fprintf(stderr, "sendto error: %s\n", strerror(errno));
   }
 }
 
-void propagate_distance_vector(int sockfd, int networks_number, struct router_addr *networks) {
+void propagate_distance_vector(int sockfd, int networks_number, struct network_addr *networks) {
   printf("Propagating distance vector\n");
   for (int i = 0; i < networks_number; i++) {
     struct in_addr broadcast_address = get_broadcast_address(networks[i]);
@@ -67,7 +56,7 @@ void propagate_distance_vector(int sockfd, int networks_number, struct router_ad
   printf("Distance vector propagated.\n\n");
 }
 
-void router_loop(int sockfd, int networks_number, struct router_addr *networks) {
+void router_loop(int sockfd, int networks_number, struct network_addr *networks) {
   printf("Starting the router loop...\n");
   for (;;) {
     listen_for_routers(sockfd, TURN_LEN_MS, networks_number, networks);
@@ -76,7 +65,7 @@ void router_loop(int sockfd, int networks_number, struct router_addr *networks)
 }
 
 int main() {
-  struct router_addr* networks;
+  struct network_addr* networks;
   int n = read_configuration(&networks);
   for (int i = 0; i < n; i++) {
     pretty_print(networks[i]);
diff --git a/Semestr 4/sieci/pracownia2/router/router_addr.c b/Semestr 4/sieci/pracownia2/router/router_addr.c
deleted file mode 100644
index 1e4c086..0000000
--- a/Semestr 4/sieci/pracownia2/router/router_addr.c
+++ /dev/null
@@ -1,32 +0,0 @@
-#include "router_addr.h"
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-
-struct in_addr get_broadcast_address(struct router_addr ra) {
-  struct in_addr result = ra.addr;
-  /* bitshift by more than 31 is UB */
-  if (ra.netmask < 32) {
-    result.s_addr |= ~((1<<ra.netmask) - 1);
-  }
-  return result;
-}
-
-void pretty_print(struct router_addr ra) {
-  char ip_addr[20];
-  inet_ntop(AF_INET, &ra.addr, ip_addr, sizeof(ip_addr));
-  printf("%s/%d distance %d\n", ip_addr, ra.netmask, ra.distance);
-}
-
-/* converts string of IP with netmask in CIDR notation to router_addr */
-struct router_addr stora(char *str) {
-  struct router_addr  result;
-  char                addr[20];
-  size_t              ip_preffix = strcspn(str, "/");
-  
-  strncpy(addr, str, strlen(str));
-  addr[ip_preffix] = 0;
-  inet_pton(AF_INET, addr, &(result.addr));
-  result.netmask = atoi(str + ip_preffix + 1);
-  return result;
-}
\ No newline at end of file
diff --git a/Semestr 4/sieci/pracownia2/router/router_addr.h b/Semestr 4/sieci/pracownia2/router/router_addr.h
deleted file mode 100644
index bebb0f5..0000000
--- a/Semestr 4/sieci/pracownia2/router/router_addr.h
+++ /dev/null
@@ -1,19 +0,0 @@
-#ifndef ROUTER_ADDR_H
-#define ROUTER_ADDR_H
-
-#include <arpa/inet.h>
-#include <stdint.h>
-
-struct router_addr {
-  struct in_addr  addr;
-  uint16_t        distance;
-  uint8_t         netmask;
-};
-
-struct in_addr get_broadcast_address(struct router_addr ra);
-
-void pretty_print(struct router_addr ra);
-
-struct router_addr stora(char *str);
-
-#endif
\ No newline at end of file
diff --git a/Semestr 4/sieci/pracownia2/router/test.c b/Semestr 4/sieci/pracownia2/router/test.c
new file mode 100644
index 0000000..ebc6df1
--- /dev/null
+++ b/Semestr 4/sieci/pracownia2/router/test.c
@@ -0,0 +1,40 @@
+#include "linked_list.h"
+#include <stdlib.h>
+#include <stdio.h>
+
+/* Prints the list of ints to stdio */
+void print_list(list_t list) {
+  printf("List: ");
+  reset(&list);
+  while (list.it != NULL) {
+    printf("%d, ", *(int *)(list.it->data));
+    iterate(&list);
+  }
+  printf("\n");
+  reset(&list);
+}
+
+int main() {
+  int n;
+  scanf("%d", &n);
+  list_t list = create_list();
+
+  for (int i = 0; i < n; i++) {
+    int t;
+    scanf("%d", &t);
+    // insert
+    if (t == 0) {
+      int val = 0;
+      scanf("%d", &val);
+      insert(&list, &val, sizeof(int));
+    }
+    if (t == 1) {
+      erase(&list);
+    }
+    if (t == 2) {
+      print_list(list);
+    }
+  }
+
+  free_list(&list);
+}
\ No newline at end of file
diff --git a/Semestr 4/sieci/pracownia2/router/utils.c b/Semestr 4/sieci/pracownia2/router/utils.c
index 9f008eb..2872a35 100644
--- a/Semestr 4/sieci/pracownia2/router/utils.c
+++ b/Semestr 4/sieci/pracownia2/router/utils.c
@@ -21,10 +21,12 @@ void bind_to_port(int sockfd, uint16_t port) {
   server_address.sin_family       = AF_INET;
   server_address.sin_port         = htons(port);
   server_address.sin_addr.s_addr  = htonl(INADDR_ANY);
+  
   if (bind(sockfd, (struct sockaddr*)&server_address, sizeof(server_address)) < 0) {
     fprintf(stderr, "Bind error: %s\n", strerror(errno));
     exit(EXIT_FAILURE);
   }
+  
   int broadcastPermission = 1;
   setsockopt (sockfd, SOL_SOCKET, SO_BROADCAST, (void *)&broadcastPermission, sizeof(broadcastPermission));
 }
@@ -38,16 +40,17 @@ int poll_socket_modify_timeout(int sockfd, int *timeout) {
     fprintf(stderr, "poll_modify_timeout: timeout is negative.\n");
     exit(EXIT_FAILURE);
   }
-  
+
   struct pollfd fds;
+  struct timespec start;
+  struct timespec finish;
+  
   fds.fd = sockfd;
   fds.events = POLLIN;
   fds.revents = 0;
-
-  struct timespec start;
   clock_gettime(CLOCK_REALTIME, &start);
-  int result = poll(&fds, 1, *timeout);
   
+  int result = poll(&fds, 1, *timeout);
   if (result == -1) {
     fprintf(stderr, "poll error: %s\n", strerror(errno));
     exit(EXIT_FAILURE);
@@ -56,15 +59,14 @@ int poll_socket_modify_timeout(int sockfd, int *timeout) {
     *timeout = 0;
     return 0;
   }
-  struct timespec finish;
+
   clock_gettime(CLOCK_REALTIME, &finish);
   *timeout -= get_time_interval(start, finish);
   printf("Timeout: %dms, time waiting: %ldms.\n", *timeout, get_time_interval(start, finish));
   return result;
 }   
 
-/* For debug purposes only */
-void recv_and_print(int sockfd, int networks_number, struct router_addr *networks) {
+void recv_and_print(int sockfd, int networks_number, struct network_addr *networks) {
   struct sockaddr_in  sender;
   socklen_t           sender_len = sizeof(sender);
   uint8_t             buffer[IP_MAXPACKET + 1];
@@ -87,4 +89,14 @@ void recv_and_print(int sockfd, int networks_number, struct router_addr *network
 
   buffer[datagram_len] = 0;
   printf("%ld-byte message: +%s+\n", datagram_len, buffer);
-}
\ No newline at end of file
+}
+
+size_t send_message(int sockfd, char *buffer, int buffer_len, struct in_addr network) {
+  struct sockaddr_in network_address;
+  bzero (&network_address, sizeof(network_address));
+  network_address.sin_family       = AF_INET;
+  network_address.sin_port         = htons(SERVER_PORT);
+  network_address.sin_addr         = network;
+  
+  return sendto(sockfd, buffer, buffer_len, 0, (struct sockaddr*) &network_address, sizeof(network_address));
+}
diff --git a/Semestr 4/sieci/pracownia2/router/utils.h b/Semestr 4/sieci/pracownia2/router/utils.h
index 3d36aed..63ad6fb 100644
--- a/Semestr 4/sieci/pracownia2/router/utils.h
+++ b/Semestr 4/sieci/pracownia2/router/utils.h
@@ -2,22 +2,35 @@
 #define UTILS_H
 #define UTILS_H
 
+#include "config.h"
 #include <stdint.h>
 #include <time.h>
 #include <poll.h>
-#include "router_addr.h"
+#include "network_addr.h"
 
 #define NS_TO_MS(X) ((long)(X) / (long)1000000)
 #define S_TO_MS(X) ((long)(X) * (long)1000)
 
+/* Returns a UDP socket. */
 int get_socket();
 
+/* Binds socket to given port and set the broadcast permission. */
 void bind_to_port(int sockfd, uint16_t port);
 
+/* Computes the time elapsed between start and finish in miliseconds. */
 long get_time_interval(struct timespec start, struct timespec finish);
 
+/* Polls given socket with given timeout and changes the timeout accordingly. */
 int poll_socket_modify_timeout(int sockfd, int *timeout);
 
-void recv_and_print(int sockfd, int networks_number, struct router_addr *networks);
+/* For debug purposes only. Recieves and prints UDP message. */
+void recv_and_print(int sockfd, int networks_number, struct network_addr *networks);
+
+/* Sends message in buffer of length buffer_len to addr through given socket. 
+ * IT DOES NOT TERMINATE THE PROGRAM IF SENDTO RETURNS ANY ERRORS! 
+ * One must handle the errors on their own. 
+ */  
+size_t send_message(int sockfd, char *buffer, int buffer_len, struct in_addr addr);
+
 
 #endif
\ No newline at end of file
diff --git a/Semestr 4/sieci/pracownia2/router/vector.h b/Semestr 4/sieci/pracownia2/router/vector.h
new file mode 100644
index 0000000..4cd0039
--- /dev/null
+++ b/Semestr 4/sieci/pracownia2/router/vector.h
@@ -0,0 +1 @@
+#ifndef 
\ No newline at end of file