From 0b53da0e1860e6dcf2b02ac02a21e9f60def58a4 Mon Sep 17 00:00:00 2001
From: Flavien Haas <flavien@MacBook-Pro-de-Flavien.local>
Date: Tue, 29 Oct 2019 09:05:24 +0100
Subject: [PATCH] traduction du programme serveur

---
 serveur_echo.c | 127 +++++++++++++++++++++++--------------------------
 1 file changed, 60 insertions(+), 67 deletions(-)

diff --git a/serveur_echo.c b/serveur_echo.c
index 2781ce3..1bb791b 100755
--- a/serveur_echo.c
+++ b/serveur_echo.c
@@ -8,84 +8,77 @@
 
 #define BUF_SIZE 500
 
-int
-main(int argc, char *argv[])
-{
-    struct addrinfo hints;
-    struct addrinfo *result, *rp;
-    int sfd, s;
-    struct sockaddr_storage peer_addr;
-    socklen_t peer_addr_len;
-    ssize_t nread;
-    char buf[BUF_SIZE];
-
-    if (argc != 2) {
-        fprintf(stderr, "Usage: %s port\n", argv[0]);
-        exit(EXIT_FAILURE);
+int main(int argc, char *argv[]){
+  struct addrinfo hints;
+  struct addrinfo *result, *rp;
+  int sfd, s;
+  struct sockaddr_storage peer_addr;
+  socklen_t peer_addr_len;
+  ssize_t nread;
+  char buf[BUF_SIZE];
+
+  if (argc != 2) {
+    fprintf(stderr, "Usage: %s port\n", argv[0]);
+    exit(EXIT_FAILURE);
+  }
+
+  //remplissage de la structure hints contenants la configuration réseau du serveur
+  memset(&hints, 0, sizeof(struct addrinfo));
+  hints.ai_family = AF_INET6;    // utilisation du serveur sur IPv6 (AF_UNSPEC pour IPv4/6)
+  hints.ai_socktype = SOCK_DGRAM; // socket en mode datagramme
+
+  s = getaddrinfo(NULL, argv[1], &hints, &result);
+  if (s != 0) {
+    fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(s));
+    exit(EXIT_FAILURE);
+  }
+
+  /* getaddrinfo () retourne une liste de structures d'adresses.
+     Essayez chaque adresse jusqu'à ce que nous ayons réussi à bind(2).
+     Si socket() (ou bind()) échoue, nous (fermons le socket et)
+     essayons l'adresse suivante */
+
+  for (rp = result; rp != NULL; rp = rp->ai_next) {
+    sfd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
+    if (sfd == -1){
+      continue;
     }
 
-    memset(&hints, 0, sizeof(struct addrinfo));
-    hints.ai_family = AF_UNSPEC;    /* Allow IPv4 or IPv6 */
-    hints.ai_socktype = SOCK_DGRAM; /* Datagram socket */
-    hints.ai_flags = AI_PASSIVE;    /* For wildcard IP address */
-    hints.ai_protocol = 0;          /* Any protocol */
-    hints.ai_canonname = NULL;
-    hints.ai_addr = NULL;
-    hints.ai_next = NULL;
-
-    s = getaddrinfo(NULL, argv[1], &hints, &result);
-    if (s != 0) {
-        fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(s));
-        exit(EXIT_FAILURE);
+    if (bind(sfd, rp->ai_addr, rp->ai_addrlen) == 0){
+      break;                             /* Succès */
     }
 
-    /* getaddrinfo() returns a list of address structures.
-       Try each address until we successfully bind(2).
-       If socket() (or bind()) fails, we (close the socket
-       and) try the next address. */
+    close(sfd);
+  }
 
-    for (rp = result; rp != NULL; rp = rp->ai_next) {
-        sfd = socket(rp->ai_family, rp->ai_socktype,
-                rp->ai_protocol);
-        if (sfd == -1)
-            continue;
+  if (rp == NULL) {                      /* Aucune adresse n'a pu marcher */
+    fprintf(stderr, "Could not bind\n");
+    exit(EXIT_FAILURE);
+  }
 
-        if (bind(sfd, rp->ai_addr, rp->ai_addrlen) == 0)
-            break;                  /* Success */
+  freeaddrinfo(result);                  /* libère le buffer */
 
-        close(sfd);
-    }
+  /* Lit les datagrammes et les renvois au client */
 
-    if (rp == NULL) {               /* No address succeeded */
-        fprintf(stderr, "Could not bind\n");
-        exit(EXIT_FAILURE);
+  for (;;) {
+    peer_addr_len = sizeof(struct sockaddr_storage);
+    nread = recvfrom(sfd, buf, BUF_SIZE, 0, (struct sockaddr *) &peer_addr, &peer_addr_len);
+    if (nread == -1){
+      continue;                          /* ignore la mauvaise requete */
     }
 
-    freeaddrinfo(result);           /* No longer needed */
-
-    /* Read datagrams and echo them back to sender */
-
-    for (;;) {
-        peer_addr_len = sizeof(struct sockaddr_storage);
-        nread = recvfrom(sfd, buf, BUF_SIZE, 0,
-                (struct sockaddr *) &peer_addr, &peer_addr_len);
-        if (nread == -1)
-            continue;               /* Ignore failed request */
+    char host[NI_MAXHOST], service[NI_MAXSERV];
 
-        char host[NI_MAXHOST], service[NI_MAXSERV];
-
-        s = getnameinfo((struct sockaddr *) &peer_addr,
-                        peer_addr_len, host, NI_MAXHOST,
-                        service, NI_MAXSERV, NI_NUMERICSERV);
-       if (s == 0)
-            printf("Received %ld bytes from %s:%s\n",
-                    (long) nread, host, service);
-        else
-            fprintf(stderr, "getnameinfo: %s\n", gai_strerror(s));
+    s = getnameinfo((struct sockaddr *) &peer_addr, peer_addr_len, host, NI_MAXHOST, service, NI_MAXSERV, NI_NUMERICSERV);
+    if (s == 0){
+      printf("Recu %ld octets de %s:%s\n", (long) nread, host, service);
+    }
+    else{
+      fprintf(stderr, "getnameinfo: %s\n", gai_strerror(s));
+    }
 
-        if (sendto(sfd, buf, nread, 0,
-                    (struct sockaddr *) &peer_addr,
-                    peer_addr_len) != nread)
-            fprintf(stderr, "Error sending response\n");
+    if (sendto(sfd, buf, nread, 0, (struct sockaddr *) &peer_addr, peer_addr_len) != nread){
+      fprintf(stderr, "Erreur d'envoi de la reponse\n");
     }
+  }
 }