Cosas de Distribuidos I.

[z.facultad/75.74/practicos.git] / practicas / pipi / src / nameserver.cpp

diff --git a/practicas/pipi/src/nameserver.cpp b/practicas/pipi/src/nameserver.cpp
index 46e571c687b0a3adf715959babd8a3aa63bb8d91..4fd894a51eaaedab6aaa2e1fec1f02e44f8268b9 100644 (file)
--- a/practicas/pipi/src/nameserver.cpp
+++ b/practicas/pipi/src/nameserver.cpp
@@ -8,8 +8,6 @@
 #include <iostream>
 #endif
 
 #include <iostream>
 #endif
 

-#define DEBUG_RESOLV
-

 NameServer::Name::Name(const std::string& s)
 {
     std::istringstream iss(s);
 NameServer::Name::Name(const std::string& s)
 {
     std::istringstream iss(s);


@@ -48,7 +46,7 @@ static std::istream& parsezone(std::istream& is, NameServer::Zone& z)
         throw std::runtime_error("Error al parsear");
     z.name = sname;
 #ifdef DEBUG_PARSER
         throw std::runtime_error("Error al parsear");
     z.name = sname;
 #ifdef DEBUG_PARSER

-    std::cerr << "parsezone: IP = " << ip << "\n\n";
+    std::cout << "NameServer::parsezone: IP = " << ip << "\n\n";

 #endif
     z.parent = IPAddr(ip);
     // un record por linea, sin líneas vacías
 #endif
     z.parent = IPAddr(ip);
     // un record por linea, sin líneas vacías


@@ -62,13 +60,13 @@ static std::istream& parsezone(std::istream& is, NameServer::Zone& z)
             throw std::runtime_error("Error al parsear");
         typedef NameServer::Record Rec;
 #ifdef DEBUG_PARSER
             throw std::runtime_error("Error al parsear");
         typedef NameServer::Record Rec;
 #ifdef DEBUG_PARSER

-        std::cerr << "parsezone: IP = " << ip << "\n\n";
+        std::cout << "NameServer::parsezone: IP = " << ip << "\n\n";

 #endif
         Rec r((type == "NS") ? Rec::NS : Rec::A, IPAddr(ip));
         z.records.insert(NameServer::Zone::records_t::value_type(key, r));
     }
 #ifdef DEBUG_PARSER
 #endif
         Rec r((type == "NS") ? Rec::NS : Rec::A, IPAddr(ip));
         z.records.insert(NameServer::Zone::records_t::value_type(key, r));
     }
 #ifdef DEBUG_PARSER

-    std::cerr << "parsezone: " << z << "\n\n";
+    std::cout << "NameServer::parsezone: " << z << "\n\n";

 #endif
     return is;
 }
 #endif
     return is;
 }


@@ -108,9 +106,15 @@ NameServer::NameServer(std::istream& is, IPIn& ipin, IPOut& ipout,
         zones.push_back(z);
         z.clear();
 #ifdef DEBUG_PARSER
         zones.push_back(z);
         z.clear();
 #ifdef DEBUG_PARSER

-        std::cerr << "NameServer: " << z << "\n\n";
+        std::cout << "NameServer::NameServer: " << z << "\n\n";

 #endif
     }
 #endif
     }

+
+#ifdef DEBUG_RESOLV
+    std::cout << "NameServer::NameServer: req_que_id = " << req_que.que_id
+        << ", res_que_id = " << res_que.que_id
+        << ", snd_que_id = " << snd_que.que_id << "\n";
+#endif

 }
 
 /// Devuelve la parte izquierda de n, si la parte derecha coincide exactamente
 }
 
 /// Devuelve la parte izquierda de n, si la parte derecha coincide exactamente


@@ -138,7 +142,8 @@ name_split(NameServer::Name n, NameServer::Name m)
         r.push_back(n[i++]);
     std::reverse(r.begin(), r.end());
 #ifdef DEBUG_NAME
         r.push_back(n[i++]);
     std::reverse(r.begin(), r.end());
 #ifdef DEBUG_NAME

-    std::cerr << "name_split(" << n << ", " << m << ") -> " << r << "\n";
+    std::cout << "NameServer::name_split(" << n << ", " << m << ") -> "
+        << r << "\n";

 #endif
     return r;
 }
 #endif
     return r;
 }


@@ -217,8 +222,12 @@ struct search_zone: std::unary_function< NameServer::Zone, bool >
 /// Resuelve un nombre de forma directa (no recursiva)
 ResolvProtoResponse NameServer::resolv_direct(const Name& n)
 {
 /// Resuelve un nombre de forma directa (no recursiva)
 ResolvProtoResponse NameServer::resolv_direct(const Name& n)
 {

+#ifdef DEBUG_TRACE
+    std::cout << "NameServer::resolv_direct()\n";
+#endif

 #ifdef DEBUG_RESOLV
 #ifdef DEBUG_RESOLV

-    std::cerr << "resolv_direct -> tratando de resolver: " << n << "\n";
+    std::cout << "NameServer::resolv_direct -> tratando de resolver: "
+        << n << "\n";

 #endif
     search_zone zs(n);
     bool found;
 #endif
     search_zone zs(n);
     bool found;


@@ -228,26 +237,39 @@ ResolvProtoResponse NameServer::resolv_direct(const Name& n)
     if (found)
     {
 #ifdef DEBUG_RESOLV
     if (found)
     {
 #ifdef DEBUG_RESOLV

-        std::cerr << "resolv_direct found (local/hijo): " << zs.resp << "\n";
+        std::cout << "NameServer::resolv_direct -> found (local/hijo): "
+            << zs.resp << "\n";

 #endif
         return zs.resp;
     }
     if (zs.local)
     {
 #ifdef DEBUG_RESOLV
 #endif
         return zs.resp;
     }
     if (zs.local)
     {
 #ifdef DEBUG_RESOLV

-        std::cerr << "resolv_direct NOT FOUND (es local pero no existe)\n";
+        std::cout << "NameServer::resolv_direct -> NOT FOUND (es local pero "
+            "no existe)\n";

 #endif
         return ResolvProtoResponse(RP_RES_NOTFOUND);
     }
 #endif
         return ResolvProtoResponse(RP_RES_NOTFOUND);
     }

-    cache_t::const_iterator i = cache.find(n);
-    // TODO TTL!?!
+    cache_t::iterator i = cache.find(n);

     if (i != cache.end())
     {
     if (i != cache.end())
     {

+        const CacheRecord& cr = i->second;

 #ifdef DEBUG_RESOLV
 #ifdef DEBUG_RESOLV

-        std::cerr << "resolv_direct found (en cache): " << i->second << "\n";
+        std::cout << "NameServer::resolv_direct -> found (en cache): "
+            << cr << "\n";

 #endif
 #endif

-        const CacheRecord& cr = i->second;
-        return ResolvProtoResponse(RP_RES_A, cr.ttl, cr.ips);
+        if (unsigned(time(NULL)) > cr.expire) // Expiró
+        {
+            cache.erase(i);
+#ifdef DEBUG_RESOLV
+            std::cout << "                          -> pero no sirve, expiró "
+                "hace unos " << (time(NULL) - cr.expire) << " segundos\n";
+#endif
+        }
+        else
+        {
+            return ResolvProtoResponse(RP_RES_A, cr.ttl, cr.ips);
+        }

     }
     if (zones.size())
     {
     }
     if (zones.size())
     {


@@ -255,13 +277,13 @@ ResolvProtoResponse NameServer::resolv_direct(const Name& n)
         for (zones_t::const_iterator i = zones.begin(); i != zones.end(); ++i)
         {
 #ifdef DEBUG_RESOLV
         for (zones_t::const_iterator i = zones.begin(); i != zones.end(); ++i)
         {
 #ifdef DEBUG_RESOLV

-            std::cerr << "resolv_direct -> evaluando padre " << i->parent
-                << "\n";
+            std::cout << "NameServer::resolv_direct -> evaluando padre "
+                << i->parent << "\n";

 #endif
             if (i->parent != IPAddr(0))
             {
 #ifdef DEBUG_RESOLV
 #endif
             if (i->parent != IPAddr(0))
             {
 #ifdef DEBUG_RESOLV

-                std::cerr << "resolv_direct found (al padre): "
+                std::cout << "NameServer::resolv_direct -> found (al padre): "

                     << i->parent << "\n";
 #endif
                 ResolvProtoResponse rpr(RP_RES_NS, i->ttl);
                     << i->parent << "\n";
 #endif
                 ResolvProtoResponse rpr(RP_RES_NS, i->ttl);


@@ -271,7 +293,7 @@ ResolvProtoResponse NameServer::resolv_direct(const Name& n)
         }
     }
 #ifdef DEBUG_RESOLV
         }
     }
 #ifdef DEBUG_RESOLV

-    std::cerr << "resolv_direct NOT FOUND (no hay padre)\n";
+    std::cout << "NameServer::resolv_direct -> NOT FOUND (no hay padre)\n";

 #endif
     // No hay padre, no puedo hacer nada más
     return ResolvProtoResponse(RP_RES_NOTFOUND);
 #endif
     // No hay padre, no puedo hacer nada más
     return ResolvProtoResponse(RP_RES_NOTFOUND);


@@ -280,19 +302,23 @@ ResolvProtoResponse NameServer::resolv_direct(const Name& n)
 /// Resuelve un nombre de forma recursiva
 ResolvProtoResponse NameServer::resolv_recursive(const Name& n)
 {
 /// Resuelve un nombre de forma recursiva
 ResolvProtoResponse NameServer::resolv_recursive(const Name& n)
 {

+#ifdef DEBUG_TRACE
+    std::cout << "NameServer::resolv_recursive()\n";
+#endif

     ResolvProtoResponse rpr = resolv_direct(n);
     switch (rpr.ret)
     {
         case RP_RES_NS:
 #ifdef DEBUG_RESOLV
     ResolvProtoResponse rpr = resolv_direct(n);
     switch (rpr.ret)
     {
         case RP_RES_NS:
 #ifdef DEBUG_RESOLV

-            std::cerr << "resolv_recursive -> redirect a " << rpr << "\n";
+            std::cout << "NameServer::resolv_recursive -> redirect a "
+                << rpr << "\n";

 #endif
             return resolv_recursive_r(n, rpr); // Sigo "bajando"
         case RP_RES_A:
 #ifdef DEBUG_RESOLV
 #endif
             return resolv_recursive_r(n, rpr); // Sigo "bajando"
         case RP_RES_A:
 #ifdef DEBUG_RESOLV

-            std::cerr << "resolv_recursive -> gotcha! " << rpr << "\n";
+            std::cout << "NameServer::resolv_recursive -> gotcha! "
+                << rpr << "\n";

 #endif
 #endif

-            // TODO agregar a cache

             break;
     }
     return rpr; // Devuelvo el A o NOTFOUND
             break;
     }
     return rpr; // Devuelvo el A o NOTFOUND


@@ -302,6 +328,9 @@ ResolvProtoResponse NameServer::resolv_recursive(const Name& n)
 ResolvProtoResponse NameServer::resolv_recursive_r(const Name& n,
         ResolvProtoResponse rpr)
 {
 ResolvProtoResponse NameServer::resolv_recursive_r(const Name& n,
         ResolvProtoResponse rpr)
 {

+#ifdef DEBUG_TRACE
+    std::cout << "NameServer::resolv_recursive_r()\n";
+#endif

     ResolvProtoResponse r;
     for (ResolvProtoResponse::ipvec_t::const_iterator ip = rpr.ips.begin();
             ip != rpr.ips.end(); ++ip)
     ResolvProtoResponse r;
     for (ResolvProtoResponse::ipvec_t::const_iterator ip = rpr.ips.begin();
             ip != rpr.ips.end(); ++ip)


@@ -311,25 +340,27 @@ ResolvProtoResponse NameServer::resolv_recursive_r(const Name& n,
         {
             case RP_RES_NS:
 #ifdef DEBUG_RESOLV
         {
             case RP_RES_NS:
 #ifdef DEBUG_RESOLV

-                std::cerr << "resolv_recursive_r -> redirect a " << r << "\n";
+                std::cout << "NameServer::resolv_recursive_r -> redirect a "
+                    << r << "\n";

 #endif
                 return resolv_recursive_r(n, r); // Sigo "bajando"
             case RP_RES_NOTFOUND:
 #ifdef DEBUG_RESOLV
 #endif
                 return resolv_recursive_r(n, r); // Sigo "bajando"
             case RP_RES_NOTFOUND:
 #ifdef DEBUG_RESOLV

-                std::cerr << "resolv_recursive_r -> NOT FOUND en " << *ip
-                    << ", sigo probando\n";
+                std::cout << "NameServer::resolv_recursive_r -> NOT FOUND en "
+                    << *ip << ", sigo probando\n";

 #endif
                 break; // Sigo probando del mismo nivel
             case RP_RES_A:
 #ifdef DEBUG_RESOLV
 #endif
                 break; // Sigo probando del mismo nivel
             case RP_RES_A:
 #ifdef DEBUG_RESOLV

-                std::cerr << "resolv_recursive_r -> gotcha! " << r << "\n";
+                std::cout << "NameServer::resolv_recursive_r -> gotcha! "
+                    << r << "\n";

 #endif
 #endif

-                // TODO agregar a cache

                 return r; // Gotcha!
         }
     }
 #ifdef DEBUG_RESOLV
                 return r; // Gotcha!
         }
     }
 #ifdef DEBUG_RESOLV

-    std::cerr << "resolv_recursive_r -> NOT FOUND, no hay más por hacer\n";
+    std::cout << "NameServer::resolv_recursive_r -> NOT FOUND, no hay más "
+        "por hacer\n";

 #endif
     return r; // NOTFOUND
 }
 #endif
     return r; // NOTFOUND
 }


@@ -337,9 +368,12 @@ ResolvProtoResponse NameServer::resolv_recursive_r(const Name& n,
 /// Consulta a otro name server sobre un nombre
 ResolvProtoResponse NameServer::query(const Name& n, const IPAddr& ip)
 {
 /// Consulta a otro name server sobre un nombre
 ResolvProtoResponse NameServer::query(const Name& n, const IPAddr& ip)
 {

+#ifdef DEBUG_TRACE
+    std::cout << "NameServer::query()\n";
+#endif

     ResolvProtoRequest r(std::string(n), RP_REQ_DIRECT);
 #ifdef DEBUG_RESOLV
     ResolvProtoRequest r(std::string(n), RP_REQ_DIRECT);
 #ifdef DEBUG_RESOLV

-    std::cerr << "query -> pidiendo " << r << " a " << ip << "\n";
+    std::cout << "NameServer::query -> pidiendo " << r << " a " << ip << "\n";

 #endif
     // Envía a través de la cola de envío
     snd_que.transmit(std::string(r), ip);
 #endif
     // Envía a través de la cola de envío
     snd_que.transmit(std::string(r), ip);


@@ -347,13 +381,20 @@ ResolvProtoResponse NameServer::query(const Name& n, const IPAddr& ip)
     std::string buf = res_que.receive(mac);
     ResolvProtoResponse resp(buf);
 #ifdef DEBUG_RESOLV
     std::string buf = res_que.receive(mac);
     ResolvProtoResponse resp(buf);
 #ifdef DEBUG_RESOLV

-    std::cerr << "query -> recibido " << resp << " de " << ip << "\n";
+    std::cout << "NameServer::query -> recibido " << resp << " de "
+        << ip << "\n";

 #endif
 #endif

+    // Agrego a cache
+    if (resp.ret == RP_RES_A)
+        cache[n] = CacheRecord(time(NULL) + resp.ttl, resp.ttl, resp.ips);

     return resp;
 }
 
 void NameServer::recv_loop()
 {
     return resp;
 }
 
 void NameServer::recv_loop()
 {

+#ifdef DEBUG_TRACE
+    std::cout << "NameServer::recv_loop()\n";
+#endif

     while (true)
     {
         IPAddr src, dst;
     while (true)
     {
         IPAddr src, dst;


@@ -391,38 +432,49 @@ void NameServer::recv_loop()
 
 void NameServer::send_loop()
 {
 
 void NameServer::send_loop()
 {

+#ifdef DEBUG_TRACE
+    std::cout << "NameServer::send_loop()\n";
+#endif
+    while (true)
+    {
+        Dev::mac_type mac = 0;
+        std::string buf = snd_que.receive(mac);
+#ifdef DEBUG_RESOLV
+        uint8_t type;
+        memcpy(&type, buf.data(), sizeof(uint8_t));
+        std::cout << "NameServer::send_loop() -> envío ";
+        if (type == RP_REQ_DIRECT || type == RP_REQ_RECURSIVE)
+            std::cout << "request " << ResolvProtoRequest(buf) << "\n";
+        else
+            std::cout << "response " << ResolvProtoResponse(buf) << "\n";
+#endif
+        ipout.send(buf, RESOLV_PROTO, IPAddr(mac));
+    }
+}
+
+void NameServer::req_loop()
+{
+#ifdef DEBUG_TRACE
+    std::cout << "NameServer::req_loop()\n";
+#endif

     while (true)
     {
     while (true)
     {

-        if (!req_que.empty())
-        {
-            Dev::mac_type mac = 0;
-            ResolvProtoRequest req(req_que.receive(mac));

 #ifdef DEBUG_RESOLV
 #ifdef DEBUG_RESOLV

-            std::cout << "NameServer::send_loop() -> recibido " << req << "\n";
+        std::cout << "----------------------------------------------------\n";

 #endif
 #endif

-            ResolvProtoResponse res
-                = (req.query_type == RP_REQ_DIRECT)
-                ? resolv_direct(req.name)
-                : resolv_recursive(req.name);
+        Dev::mac_type mac = 0;
+        ResolvProtoRequest req(req_que.receive(mac));

 #ifdef DEBUG_RESOLV
 #ifdef DEBUG_RESOLV

-            std::cout << "NameServer::send_loop() -> respondo " << res << "\n";
+        std::cout << "NameServer::req_loop() -> recibido " << req << "\n";

 #endif
 #endif

-            ipout.send(res, RESOLV_PROTO, IPAddr(mac));
-        }
-        else if (!snd_que.empty()) // Hay un request para enviar
-        {
-            Dev::mac_type mac = 0;
-            std::string buf = snd_que.receive(mac);
+        ResolvProtoResponse res
+            = (req.query_type == RP_REQ_DIRECT)
+            ? resolv_direct(req.name)
+            : resolv_recursive(req.name);

 #ifdef DEBUG_RESOLV
 #ifdef DEBUG_RESOLV

-            std::cout << "NameServer::send_loop() -> envío request "
-                << ResolvProtoRequest(buf) << "\n";
+        std::cout << "NameServer::req_loop() -> respondo " << res << "\n";

 #endif
 #endif

-            ipout.send(buf, RESOLV_PROTO, IPAddr(mac));
-        }
-        else // No hay nada, esperamos un rato
-        {
-            usleep(10000);
-        }
+        snd_que.transmit(std::string(res), IPAddr(mac));

     }
 }
 
     }
 }
 


@@ -455,7 +507,8 @@ std::ostream& operator<< (std::ostream& os, const NameServer::Zone& z)
 
 std::ostream& operator<< (std::ostream& os, const NameServer::CacheRecord& cr)
 {
 
 std::ostream& operator<< (std::ostream& os, const NameServer::CacheRecord& cr)
 {

-    os << "CacheRecord(ttl=" << cr.ttl << ", records=";
+    os << "CacheRecord(expire=" << cr.expire << " [now=" << time(NULL)
+        << "], ttl=" << cr.ttl << ", records=";

     std::copy(cr.ips.begin(), cr.ips.end(),
             std::ostream_iterator< IPAddr >(os, ","));
     return os << ")";
     std::copy(cr.ips.begin(), cr.ips.end(),
             std::ostream_iterator< IPAddr >(os, ","));
     return os << ")";