it works except the terminal is echoing

when ssh is called with '-tt'

it echoes back its stdin to the terminal, which dumps the source code of
the rpc there

it echoes before the remote bash code even runs, like how the terminal
sometimes buffers input in the display when there is nothing on the
other end listening for it.

the solution is probably running 'ssh' from within 'socat' as documented
in socat(1)

1 files changed, 38 insertions, 25 deletions

diff --git a/src/rpc.bash b/src/rpc.bash
index eb41538..44f7020 100644
--- a/src/rpc.bash
+++ b/src/rpc.bash
@@ -50,22 +50,28 @@ recursive_dependencies()
 
 # Input: $BASH_RPC_REMOTE_DEST - hostname passed to ssh (uses ssh host aliases)
 # Input: $BASH_RPC_SSH_OPTIONS - option arguments passed to ssh (they precede '--')
-# Input: $1 - bash shell script source code to run remotely
-# Input: $2, $3, ... - command line arguments passed to the remote bash shell
-# Input: stdin, stdout, stderr: passed to ssh
+# Input; $BASH_RPC_STDIN_IS_TTY - controls whether to allocate ssh pty.  Doesn't work.
+# Input: $1 - shell script source code to run in the remote bash
+# Input: $2, $3, ... - command line arguments passed to the remote bash
+# Input: stdin, stdout, stderr: passed to the remote bash over ssh
+# Input: "$0" - copied to remote bash's $0
+# Input: "$SHELL" - remote shell to launch (better be bash)
 bash_rpc_remote_run_script()
 {
-        (
-                local script="$1"
-                shift
-                set -- "$SHELL" -c "${script@Q}" "$0" "${@@Q}"
-                set -x
-                exec ssh \
-                        "${BASH_RPC_SSH_OPTIONS[@]}" \
-                        -- \
-                        "${BASH_RPC_REMOTE_DEST:-localhost}" \
-                        "$@"
-        )
+        local script="$1"
+        shift
+        exec ssh \
+                "${BASH_RPC_SSH_OPTIONS[@]}" -- \
+                "${BASH_RPC_REMOTE_DEST:-localhost}" \
+                "$SHELL" -c "${script@Q}" "$0" "${@@Q}"
+}
+
+with_ssh_option()
+{
+        local BASH_RPC_SSH_OPTIONS
+        BASH_RPC_SSH_OPTIONS+=("$1")
+        shift
+        "$@"
 }
 
 # Preserves the rest of stdin for the command.
@@ -73,14 +79,20 @@ bash_rpc_eval_stdin()
 {
         [ "$1" -gt 0 ] || return
         read -N"$1" -r || return
-        shift # prepare "$@" for script execution context
-        source <(printf '%s' "$REPLY" | tr -d '\015')
+
+        # Prepare "$@" for script execution context.
+        shift
+
+        # Even unset REPLY to leave pristine environment.
+        eval "unset REPLY; $(cat <<< "$REPLY")"
 }
 
 remote_run_function_simple()
 {
         script_source=$(declare -f "$1" && printf '"$@";\n')
-        bash_rpc_remote_run_script "$script_source" "$@"
+        bash_rpc_remote_run_script  \
+                "$script_source" \
+                "$@"
 }
 
 remote_run_function()
@@ -91,15 +103,16 @@ remote_run_function()
                 declare -f $funcs
                 printf '"$@"\n' "$main"
         )
-        BASH_RPC_SSH_OPTIONS=(-tt)
+
+        local BASH_RPC_STDIN_IS_TTY=$([ ! -t 0 ] || echo y)
         {
                 printf '%s' "$stage2_source"
-                if [ -t 0 ]
-                then
-                        socat stdio PTY
-                else
-                        cat
-                fi
-        } | remote_run_function_simple bash_rpc_eval_stdin "${#stage2_source}" "$@"
+                cat
+        } |
+                ${BASH_RPC_STDIN_IS_TTY:+ with_ssh_option '-tt'} \
+                remote_run_function_simple \
+                        bash_rpc_eval_stdin \
+                                "${#stage2_source}" \
+                                "$@"
 }