Added loss max management

src/mictcp.c

@@ -6,21 +6,137 @@
 #define COLOR_BOLD   "\x1b[1m"
 #define COLOR_RESET   "\x1b[0m"
 
-#define LOSS_RATE 5
+#define DEBUG 1
+
+#define LOSS_RATE 2
 #define TIMEOUT 2
+#define MAX_LOSS_RATE 2
+#define LIST_LENGTH 200
 
 struct mic_tcp_sock g_sock;
 int next_msg_num;
 
+struct node {
+    int isSuccess;
+    struct node *previous;
+};
+
+struct {
+    struct node *head;
+    struct node *tail;
+    int size;
+    int errorNumber;
+} list;
+
+/**
+ * Gets current loss rate
+ *
+ * @return
+ */
+int getLossRate() {
+    if (list.size > 0)
+        return (100 * list.errorNumber / list.size);
+    else
+        return 1;
+}
+
+/**
+ * Checks if the current loss rate is acceptable
+ *
+ * @return
+ */
+int isLossAcceptable() {
+    return getLossRate() <= MAX_LOSS_RATE;
+}
+
+/**
+ * Remove last element from the list and remove a success from count if removed element was a success
+ */
+void popLast() {
+    if (list.size > 0 ) {
+        struct node *last = list.tail;
+        list.tail = last->previous;
+        list.size--;
+        if (last->isSuccess != 1)
+            list.errorNumber--;
+        free(last);
+    }
+}
+
+/**
+ * Inserts a new link at the front of the list.
+ * If the list has reached its max length after insertion, remove last element
+ *
+ * @param isSuccess
+ */
+void insertFirst(int isSuccess) {
+    struct node *link = (struct node*) malloc(sizeof(struct node));
+    link->isSuccess = isSuccess;
+    link->previous = NULL;
+
+    if (list.size > 0)
+        list.head->previous = link;
+    else
+        list.tail = link;
+    list.head = link;
+
+    if (isSuccess != 1)
+        list.errorNumber++;
+
+    list.size++;
+
+    if (list.size > LIST_LENGTH)
+        popLast();
+}
+
+void clearList() {
+    while (list.size > 0) {
+        popLast();
+    }
+}
+
+/**
+ * Saves a network error in the list
+ */
+void saveError() {
+    insertFirst(0);
+}
+
+/**
+ * Saves a network success in the list
+ */
+void saveSuccess() {
+    insertFirst(1);
+}
+
+void printList() {
+    if (DEBUG) {
+        printf("========= LIST =========\n");
+        printf("size: %d\n", list.size);
+        printf("errorNumber: %d\n", list.errorNumber);
+        printf("lossRate: %d\n", getLossRate());
+        printf("isLossAcceptable: %d\n", isLossAcceptable());
+
+        if (list.size > 0) {
+            printf("head: %d\n", list.head->isSuccess);
+            printf("tail: %d\n", list.tail->isSuccess);
+        }
+        printf("========================\n");
+    }
+}
+
 /**
  * Permet de créer un socket entre l’application et MIC-TCP.
  * @return le descripteur du socket ou bien -1 en cas d'erreur.
  */
 int mic_tcp_socket(start_mode sm) {
     int result;
+    if (DEBUG) {
         printf("[MIC-TCP] Appel de la fonction: ");
         printf(__FUNCTION__);
         printf("\n");
+    }
+
     result = initialize_components(sm); /* Appel obligatoire */
     set_loss_rate(LOSS_RATE);
 
@@ -28,6 +144,9 @@ int mic_tcp_socket(start_mode sm) {
     g_sock.state = IDLE;
     next_msg_num = 1;
 
+    list.size = 0;
+    list.errorNumber = 0;
+
     return result;
 }
 
@@ -36,9 +155,11 @@ int mic_tcp_socket(start_mode sm) {
  * @return 0 si succès, et -1 en cas d’échec.
  */
 int mic_tcp_bind(int socket, mic_tcp_sock_addr addr) {
+    if (DEBUG) {
         printf("[MIC-TCP] Appel de la fonction: ");
         printf(__FUNCTION__);
         printf("\n");
+    }
 
     int result = 0;
 
@@ -52,9 +173,11 @@ int mic_tcp_bind(int socket, mic_tcp_sock_addr addr) {
  * @return 0 si succès, -1 si erreur.
  */
 int mic_tcp_accept(int socket, mic_tcp_sock_addr *addr) {
+    if (DEBUG) {
         printf("[MIC-TCP] Appel de la fonction: ");
         printf(__FUNCTION__);
         printf("\n");
+    }
 
     int result = 0;
 
@@ -68,9 +191,11 @@ int mic_tcp_accept(int socket, mic_tcp_sock_addr *addr) {
  * @return 0 si la connexion est établie, et -1 en cas d’échec
  */
 int mic_tcp_connect(int socket, mic_tcp_sock_addr addr) {
+    if (DEBUG) {
         printf("[MIC-TCP] Appel de la fonction: ");
         printf(__FUNCTION__);
         printf("\n");
+    }
 
     int result = 0;
 
@@ -85,12 +210,15 @@ int mic_tcp_connect(int socket, mic_tcp_sock_addr addr) {
  * @return la taille des données envoyées, et -1 en cas d'erreur
  */
 int mic_tcp_send(int socket, char *mesg, int mesg_size) {
+    if (DEBUG) {
         printf("[MIC-TCP] Appel de la fonction: ");
         printf(__FUNCTION__);
         printf("\n");
-    int result = -1;
+    }
+    int result;
+    int errorDetected = 0;
 
-    while (result == -1) {
+    do {
         struct mic_tcp_pdu pdu;
         pdu.payload.data = mesg;
         pdu.payload.size = mesg_size;
@@ -103,27 +231,39 @@ int mic_tcp_send(int socket, char *mesg, int mesg_size) {
         pdu.header.ack = 0;
         pdu.header.fin = 0;
 
+        if (DEBUG)
             printf("\n[MIC-TCP] Sending PDU\n");
+
         if ((result = IP_send(pdu, g_sock.addr)) != -1) {
             struct mic_tcp_pdu rcv_pdu;
             struct mic_tcp_sock_addr rcv_sock_addr;
+            if (DEBUG)
                 printf("[MIC-TCP] Waiting for ACK\n");
+
             result = IP_recv(&rcv_pdu, &rcv_sock_addr, TIMEOUT);
-            if (result == -1)
+            if (result == -1 && DEBUG)
                 printf("[MIC-TCP] "COLOR_BOLD"Timeout"COLOR_RESET"\n");
             else if (rcv_pdu.header.ack_num != next_msg_num + 1) {
+                if (DEBUG) {
                     printf("[MIC-TCP] Received ACK: %d | "COLOR_RED"INVALID"COLOR_RESET"\n", rcv_pdu.header.ack_num);
                     printf("[MIC-TCP]    | Expected: %d\n", next_msg_num + 1);
                     printf("[MIC-TCP]    | Received: %d\n", rcv_pdu.header.ack_num);
-                result = -1;
-            } else
-                printf("[MIC-TCP] Received ACK: "COLOR_GREEN"VALID"COLOR_RESET"\n");
-        } else
-            printf("[MIC-TCP] Ip_send "COLOR_RED"ERROR"COLOR_RESET"\n");
                 }
+                result = -1;
+            } else if (DEBUG)
+                printf("[MIC-TCP] Received ACK: "COLOR_GREEN"VALID"COLOR_RESET"\n");
+        } else if (DEBUG)
+            printf("[MIC-TCP] Ip_send "COLOR_RED"ERROR"COLOR_RESET"\n");
+
+        if (result == -1 && errorDetected == 0) {
+            errorDetected = 1;
+            saveError();
+        }else
+            saveSuccess();
+        printList();
+    } while (result == -1 && isLossAcceptable() == 0);
 
     next_msg_num = next_msg_num + 1;
-
     return result;
 }
 
@@ -134,9 +274,11 @@ int mic_tcp_send(int socket, char *mesg, int mesg_size) {
  * NB : cette fonction fait appel à la fonction app_buffer_get()
  */
 int mic_tcp_recv(int socket, char *mesg, int max_mesg_size) {
+    if (DEBUG) {
         printf("[MIC-TCP] Appel de la fonction: ");
         printf(__FUNCTION__);
         printf("\n");
+    }
 
     int result = -1;
 
@@ -157,12 +299,14 @@ int mic_tcp_recv(int socket, char *mesg, int max_mesg_size) {
  * @return 0 si tout se passe bien et -1 en cas d'erreur
  */
 int mic_tcp_close(int socket) {
+    if (DEBUG) {
         printf("[MIC-TCP] Appel de la fonction :  ");
         printf(__FUNCTION__);
         printf("\n");
+    }
 
     g_sock.state = CLOSED;
-
+    clearList();
     return -1;
 }
 
@@ -173,9 +317,11 @@ int mic_tcp_close(int socket) {
  * app_buffer_put().
  */
 void process_received_PDU(mic_tcp_pdu pdu, mic_tcp_sock_addr addr) {
+    if (DEBUG) {
         printf("[MIC-TCP] Appel de la fonction: ");
         printf(__FUNCTION__);
         printf("\n");
+    }
 
     struct mic_tcp_pdu ack_pdu;
     ack_pdu.header.source_port = 0;
@@ -185,17 +331,20 @@ void process_received_PDU(mic_tcp_pdu pdu, mic_tcp_sock_addr addr) {
     ack_pdu.header.ack = 0;
     ack_pdu.header.fin = 0;
 
-    if (pdu.header.seq_num == next_msg_num) {
+    if (pdu.header.seq_num >= next_msg_num) {
-        next_msg_num = next_msg_num + 1;
+        next_msg_num = pdu.header.seq_num + 1;
         app_buffer_put(pdu.payload);
+        if (DEBUG)
             printf("[MIC-TCP] Received PDU: "COLOR_GREEN"VALID"COLOR_RESET"\n");
-    } else {
+    } else if (DEBUG) {
         printf("[MIC-TCP] Received PDU: "COLOR_RED"INVALID"COLOR_RESET"\n");
         printf("[MIC-TCP]    | Expected: %d\n", next_msg_num);
         printf("[MIC-TCP]    | Received: %d\n", pdu.header.seq_num);
     }
 
-    ack_pdu.header.ack_num = next_msg_num;
+    if (DEBUG)
         printf("[MIC-TCP] Sending ack: %d\n", next_msg_num);
+
+    ack_pdu.header.ack_num = next_msg_num;
     IP_send(ack_pdu, addr);
 }