Allow ssh_session_info() to work for disconnected sessions (#59)

Co-authored-by: Jeroen Ooms <jeroenooms@gmail.com>

Author: billdenney

NEWS

@@ -1,6 +1,7 @@
 0.8.3
   - Windows: update to libssh 0.10.5
   - scp_upload() now copies the file mode permissions similar to scp -p
+  - ssh_session_info() now works for disconnected sessions
 
 0.8.2
   - Fix strict-prototypes warnings

R/connect.R

@@ -51,7 +51,8 @@ ssh_connect <- function(host, keyfile = NULL, passwd = askpass, verbose = FALSE)
 #' @aliases ssh_info
 #' @useDynLib ssh C_ssh_info
 ssh_session_info <- function(session){
-  assert_session(session)
+  if(!inherits(session, "ssh_session"))
+    stop('Argument "session" must be an ssh session', call. = FALSE)
   out <- .Call(C_ssh_info, session)
   structure(out, names = c("user", "host", "identity", "port", "connected", "sha1"))
 }
@@ -109,14 +110,16 @@ me <- function(){
 }
 
 assert_session <- function(x){
-  if(!inherits(x, "ssh_session"))
-    stop('Argument "session" must be an ssh session', call. = FALSE)
+  info <- ssh_info(x)
+  if(isFALSE(info$connected))
+    stop('SSH session has been disconnected. Please connect to a new session', call. = FALSE)
 }
 
 #' @export
 print.ssh_session <- function(x, ...){
   info <- ssh_session_info(x)
-  cat(sprintf("<ssh session>\nconnected: %s@%s:%d\nserver: %s\n", info$user, info$host, info$port, info$sha1))
+  status <- ifelse(info$connected, 'connected', 'disconnected')
+  cat(sprintf("<ssh session>\n%s@%s:%d (%s)\nserver: %s\n", info$user, info$host, info$port, status, info$sha1))
 }
 
 #' @export

src/session.c

@@ -4,8 +4,8 @@ ssh_session ssh_ptr_get(SEXP ptr){
   ssh_session ssh = (ssh_session) R_ExternalPtrAddr(ptr);
   if(ssh == NULL)
     Rf_error("SSH session pointer is dead");
-  if(!ssh_is_connected(ssh))
-    Rf_error("ssh session has been disconnected");
+  //if(!ssh_is_connected(ssh))
+  //  Rf_error("ssh session has been disconnected");
   return ssh;
 }
 
@@ -212,17 +212,18 @@ SEXP C_ssh_info(SEXP ptr){
   ssh_key key;
   unsigned char * hash = NULL;
   size_t hlen = 0;
-  assert_or_disconnect(myssh_get_publickey(ssh, &key), "ssh_get_publickey", ssh);
-  assert_or_disconnect(ssh_get_publickey_hash(key, SSH_PUBLICKEY_HASH_SHA1, &hash, &hlen), "ssh_get_publickey_hash", ssh);
+  if (connected) {
+    assert_or_disconnect(myssh_get_publickey(ssh, &key), "ssh_get_publickey", ssh);
+    assert_or_disconnect(ssh_get_publickey_hash(key, SSH_PUBLICKEY_HASH_SHA1, &hash, &hlen), "ssh_get_publickey_hash", ssh);
+  }
 
   SEXP out = PROTECT(Rf_allocVector(VECSXP, 6));
   SET_VECTOR_ELT(out, 0, make_string(user));
   SET_VECTOR_ELT(out, 1, make_string(host));
   SET_VECTOR_ELT(out, 2, make_string(identity));
   SET_VECTOR_ELT(out, 3, Rf_ScalarInteger(port));
   SET_VECTOR_ELT(out, 4, Rf_ScalarLogical(connected));
-  SET_VECTOR_ELT(out, 5, make_string(ssh_get_hexa(hash, hlen)));
-
+  SET_VECTOR_ELT(out, 5, connected ? make_string(ssh_get_hexa(hash, hlen)) : Rf_ScalarString(NA_STRING));
   if(user) ssh_string_free_char(user);
   if(host) ssh_string_free_char(host);
   if(identity) ssh_string_free_char(identity);