Just use raw close() for discard

contrib/ruby/test/client_test.rb

@@ -903,6 +903,18 @@ def test_close_terminate_parent_connection
     assert_match "TRILOGY_CLOSED_CONNECTION", error.message
   end
 
+  def test_discard_closes_connection
+    client = new_tcp_client
+
+    assert_equal [1], client.query("SELECT 1").to_a.first
+
+    client.discard!
+
+    assert_raises Trilogy::ConnectionClosed do
+      client.query("SELECT 1")
+    end
+  end
+
   def test_discard_doesnt_terminate_parent_connection
     skip("Fork isn't supported on this platform") unless Process.respond_to?(:fork)
 

inc/trilogy/socket.h

@@ -76,6 +76,7 @@ typedef struct trilogy_sock_t {
     int (*wait_cb)(struct trilogy_sock_t *self, trilogy_wait_t wait);
     int (*shutdown_cb)(struct trilogy_sock_t *self);
     int (*close_cb)(struct trilogy_sock_t *self);
+    int (*discard_cb)(struct trilogy_sock_t *self);
     int (*fd_cb)(struct trilogy_sock_t *self);
 
     trilogy_sockopt_t opts;
@@ -102,6 +103,7 @@ static inline int trilogy_sock_wait_write(trilogy_sock_t *sock) { return sock->w
 static inline int trilogy_sock_shutdown(trilogy_sock_t *sock) { return sock->shutdown_cb(sock); }
 
 static inline int trilogy_sock_close(trilogy_sock_t *sock) { return sock->close_cb(sock); }
+static inline int trilogy_sock_discard(trilogy_sock_t *sock) { return sock->discard_cb(sock); }
 
 static inline int trilogy_sock_fd(trilogy_sock_t *sock) { return sock->fd_cb(sock); }
 

src/client.c

@@ -768,6 +768,7 @@ int trilogy_discard(trilogy_conn_t *conn)
 {
     int rc = trilogy_sock_discard(conn->socket);
     if (rc == TRILOGY_OK) {
+        conn->socket = NULL;
         trilogy_free(conn);
     }
     return rc;

src/socket.c

@@ -109,6 +109,9 @@ static int _cb_raw_close(trilogy_sock_t *_sock)
     return rc;
 }
 
+// Close and discard are the same for a raw socket
+#define _cb_raw_discard _cb_raw_close
+
 static int _cb_raw_shutdown(trilogy_sock_t *_sock) { return shutdown(trilogy_sock_fd(_sock), SHUT_RDWR); }
 
 static int set_nonblocking_fd(int sock)
@@ -235,6 +238,7 @@ trilogy_sock_t *trilogy_sock_new(const trilogy_sockopt_t *opts)
     sock->base.wait_cb = _cb_wait;
     sock->base.shutdown_cb = _cb_raw_shutdown;
     sock->base.close_cb = _cb_raw_close;
+    sock->base.discard_cb = _cb_raw_discard;
     sock->base.fd_cb = _cb_raw_fd;
     sock->base.opts = *opts;
 
@@ -347,6 +351,7 @@ static int _cb_ssl_shutdown(trilogy_sock_t *_sock)
     sock->base.write_cb = _cb_raw_write;
     sock->base.shutdown_cb = _cb_raw_shutdown;
     sock->base.close_cb = _cb_raw_close;
+    sock->base.discard_cb = _cb_raw_discard;
     sock->ssl = NULL;
 
     return _cb_raw_shutdown(_sock);
@@ -363,6 +368,16 @@ static int _cb_ssl_close(trilogy_sock_t *_sock)
     return _cb_raw_close(_sock);
 }
 
+static int _cb_ssl_discard(trilogy_sock_t *_sock) {
+    struct trilogy_sock *sock = (struct trilogy_sock *)_sock;
+    if (sock->ssl != NULL) {
+        // unlike close, we do not want to send SSL_shutdown
+        SSL_free(sock->ssl);
+        sock->ssl = NULL;
+    }
+    return _cb_raw_close(_sock);
+}
+
 #if OPENSSL_VERSION_NUMBER >= 0x1010000fL
 
 static int trilogy_tls_version_map[] = {0, TLS1_VERSION, TLS1_1_VERSION, TLS1_2_VERSION
@@ -614,35 +629,11 @@ int trilogy_sock_upgrade_ssl(trilogy_sock_t *_sock)
     sock->base.write_cb = _cb_ssl_write;
     sock->base.shutdown_cb = _cb_ssl_shutdown;
     sock->base.close_cb = _cb_ssl_close;
+    sock->base.discard_cb = _cb_ssl_discard;
     return TRILOGY_OK;
 
 fail:
     SSL_free(sock->ssl);
     sock->ssl = NULL;
     return TRILOGY_OPENSSL_ERR;
 }
-
-int trilogy_sock_discard(trilogy_sock_t *_sock)
-{
-    struct trilogy_sock *sock = (struct trilogy_sock *)_sock;
-
-    if (sock->fd < 0) {
-        return TRILOGY_OK;
-    }
-
-    int null_fd = open("/dev/null", O_RDWR | O_CLOEXEC);
-    if (null_fd < 0) {
-        return TRILOGY_SYSERR;
-    }
-
-    if (dup2(null_fd, sock->fd) < 0) {
-        close(null_fd);
-        return TRILOGY_SYSERR;
-    }
-
-    if (close(null_fd) < 0) {
-        return TRILOGY_SYSERR;
-    }
-
-    return TRILOGY_OK;
-}