Add an async helper function to connect an rpc context to a program/version

diff --git a/include/nfsc/libnfs-raw.h b/include/nfsc/libnfs-raw.h
index 47a6333f3d209b2f5912a27812184d7bfcfd6836..b37d67cc94135287e2502f1d2e283aa46b09f486 100644 (file)
--- a/include/nfsc/libnfs-raw.h
+++ b/include/nfsc/libnfs-raw.h
@@ -78,6 +78,21 @@ void rpc_set_next_xid(struct rpc_context *rpc, uint32_t xid);
  *                    : data is NULL.
  */
 int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data);
+/*
+ * Async function to connect to a specific RPC program/version
+ * Function returns
+ *  0 : The connection was initiated. Once the connection establish finishes, the callback will be invoked.
+ * <0 : An error occured when trying to set up the connection. The callback will not be invoked.
+ *
+ * When the callback is invoked, status indicates the result:
+ * RPC_STATUS_SUCCESS : The tcp connection was successfully established.
+ *                      data is NULL.
+ * RPC_STATUS_ERROR   : The connection failed to establish.
+ *                      data is the erro string.
+ * RPC_STATUS_CANCEL  : The connection attempt was aborted before it could complete.
+ *                    : data is NULL.
+ */
+int rpc_connect_program_async(struct rpc_context *rpc, char *server, int program, int version, rpc_cb cb, void *private_data);
 /*
  * When disconnecting a connection in flight. All commands in flight will be called with the callback
  * and status RPC_STATUS_ERROR. Data will be the error string for the disconnection.

diff --git a/lib/libnfs.c b/lib/libnfs.c
index 0b831234ac0e84479d0847bf0cfc0e88c28972a5..8a2f16fcc21419dcae10361cec7013722396fe2c 100644 (file)
--- a/lib/libnfs.c
+++ b/lib/libnfs.c
@@ -219,6 +219,155 @@ void nfs_destroy_context(struct nfs_context *nfs)
        free(nfs);
 }
 
+struct rpc_cb_data {
+       char *server;
+       uint32_t program;
+       uint32_t version;
+
+       rpc_cb cb;
+       void *private_data;
+};       
+
+void free_rpc_cb_data(struct rpc_cb_data *data)
+{
+       free(data->server);
+       data->server = NULL;
+       free(data);
+}
+
+static void rpc_connect_program_4_cb(struct rpc_context *rpc, int status, void *command_data, void *private_data)
+{
+       struct rpc_cb_data *data = private_data;
+
+       assert(rpc->magic == RPC_CONTEXT_MAGIC);
+
+       /* Dont want any more callbacks even if the socket is closed */
+       rpc->connect_cb = NULL;
+
+       if (status == RPC_STATUS_ERROR) {
+               data->cb(rpc, status, command_data, data->private_data);
+               free_rpc_cb_data(data);
+               return;
+       }
+       if (status == RPC_STATUS_CANCEL) {
+               data->cb(rpc, status, "Command was cancelled", data->private_data);
+               free_rpc_cb_data(data);
+               return;
+       }
+
+       data->cb(rpc, status, NULL, data->private_data);
+       free_rpc_cb_data(data);
+}
+
+static void rpc_connect_program_3_cb(struct rpc_context *rpc, int status, void *command_data, void *private_data)
+{
+       struct rpc_cb_data *data = private_data;
+       uint32_t rpc_port;
+
+       assert(rpc->magic == RPC_CONTEXT_MAGIC);
+
+       if (status == RPC_STATUS_ERROR) {       
+               data->cb(rpc, status, command_data, data->private_data);
+               free_rpc_cb_data(data);
+               return;
+       }
+       if (status == RPC_STATUS_CANCEL) {
+               data->cb(rpc, status, "Command was cancelled", data->private_data);
+               free_rpc_cb_data(data);
+               return;
+       }
+
+       rpc_port = *(uint32_t *)command_data;
+       if (rpc_port == 0) {
+               rpc_set_error(rpc, "RPC error. Program is not available on %s", data->server);
+               data->cb(rpc, RPC_STATUS_ERROR, rpc_get_error(rpc), data->private_data);
+               free_rpc_cb_data(data);
+               return;
+       }
+
+       rpc_disconnect(rpc, "normal disconnect");
+       if (rpc_connect_async(rpc, data->server, rpc_port, rpc_connect_program_4_cb, data) != 0) {
+               data->cb(rpc, status, command_data, data->private_data);
+               free_rpc_cb_data(data);
+               return;
+       }
+}
+
+static void rpc_connect_program_2_cb(struct rpc_context *rpc, int status, void *command_data, void *private_data)
+{
+       struct rpc_cb_data *data = private_data;
+
+       assert(rpc->magic == RPC_CONTEXT_MAGIC);
+
+       if (status == RPC_STATUS_ERROR) {
+               data->cb(rpc, status, command_data, data->private_data);
+               free_rpc_cb_data(data);
+               return;
+       }
+       if (status == RPC_STATUS_CANCEL) {
+               data->cb(rpc, status, "Command was cancelled", data->private_data);
+               free_rpc_cb_data(data);
+               return;
+       }
+
+       if (rpc_pmap_getport_async(rpc, data->program, data->version, IPPROTO_TCP, rpc_connect_program_3_cb, private_data) != 0) {
+               data->cb(rpc, status, command_data, data->private_data);
+               free_rpc_cb_data(data);
+               return;
+       }
+}
+
+static void rpc_connect_program_1_cb(struct rpc_context *rpc, int status, void *command_data, void *private_data)
+{
+       struct rpc_cb_data *data = private_data;
+
+       assert(rpc->magic == RPC_CONTEXT_MAGIC);
+
+       /* Dont want any more callbacks even if the socket is closed */
+       rpc->connect_cb = NULL;
+
+       if (status == RPC_STATUS_ERROR) {
+               data->cb(rpc, status, command_data, data->private_data);
+               free_rpc_cb_data(data);
+               return;
+       }
+       if (status == RPC_STATUS_CANCEL) {
+               data->cb(rpc, status, "Command was cancelled", data->private_data);
+               free_rpc_cb_data(data);
+               return;
+       }
+
+       if (rpc_pmap_null_async(rpc, rpc_connect_program_2_cb, data) != 0) {
+               data->cb(rpc, status, command_data, data->private_data);
+               free_rpc_cb_data(data);
+               return;
+       }
+}
+
+int rpc_connect_program_async(struct rpc_context *rpc, char *server, int program, int version, rpc_cb cb, void *private_data)
+{
+       struct rpc_cb_data *data;
+
+       data = malloc(sizeof(struct rpc_cb_data));
+       if (data == NULL) {
+               return -1;
+       }
+       memset(data, 0, sizeof(struct rpc_cb_data));
+       data->server       = strdup(server);
+       data->program      = program;
+       data->version      = version;
+
+       data->cb           = cb;
+       data->private_data = private_data;
+
+       if (rpc_connect_async(rpc, server, 111, rpc_connect_program_1_cb, data) != 0) {
+               rpc_set_error(rpc, "Failed to start connection");
+               free_rpc_cb_data(data);
+               return -1;
+       }
+       return 0;
+}
+
 void free_nfs_cb_data(struct nfs_cb_data *data)
 {
        if (data->saved_path != NULL) {