eliminate global value for *CONNECTION*

Signed-off-by: Sean Whitton <spwhitton@spwhitton.name>

4 files changed, 25 insertions, 39 deletions

diff --git a/src/connection.lisp b/src/connection.lisp
index 6efce31..f839a65 100644
--- a/src/connection.lisp
+++ b/src/connection.lisp
@@ -20,12 +20,9 @@
 
 ;;;; Connections
 
-;; global value gets set in connection/local.lisp, but the symbol is not
-;; exported as it should only get bound by DEPLOY*
 (defvar *connection* nil
   "Object representing the currently active connection.
-Connections dynamically bind this variable and then apply properties.  Its
-global value should be regarded as a constant.")
+Deployments dynamically bind this variable and then apply properties.")
 
 ;; generic function operating on keywords which identify connection types
 (defgeneric establish-connection (type remaining &key)
diff --git a/src/connection/local.lisp b/src/connection/local.lisp
index 4de70c1..a8a967c 100644
--- a/src/connection/local.lisp
+++ b/src/connection/local.lisp
@@ -76,11 +76,3 @@ root Lisp is running on, as the root Lisp's uid."))
 
 (defmethod connection-upload ((connection local-connection) from to)
   (copy-file from to))
-
-;; set the root Lisp's connection context now we've defined its value -- other
-;; implementations of ESTABLISH-CONNECTION will rely on this when they call
-;; RUN, READFILE etc.
-(eval-when (:load-toplevel :execute)
-  (unless consfigurator::*connection*
-    (setq consfigurator::*connection*
-	  (make-instance 'local-connection))))
diff --git a/src/data.lisp b/src/data.lisp
index 63d5e2d..a264030 100644
--- a/src/data.lisp
+++ b/src/data.lisp
@@ -345,9 +345,6 @@ of the current connection, where each entry is of the form
 		    "-type" "f" "-printf" "%P\\n")
 	    (and (zerop exit) (lines out)))))
 
-;; we can't just default REMAINING to :LOCAL in the lambda list because it is
-;; legitimate for callers to explicitly pass nil.
-;;
 ;; TODO on remote side, catch read errors and signal our own which says
 ;; something more specific -- "This has probably been caused by an attempt to
 ;; use a property application specification or set of static informational
@@ -412,8 +409,7 @@ achieved by sending the return value of this function into a REPL's stdin."
 		 (require "asdf")
 		 (let ((*standard-output* *error-output*))
 		   ,(wrap load-forms))
-		 ,(wrap `((deploy* ',(or remaining-connections :local)
-				   ,*host*)))))))))
+		 ,(wrap `((deploy* ',remaining-connections ,*host*)))))))))
 
 (defun request-lisp-systems ()
   "Request that all Lisp systems required by the host currently being deployed
diff --git a/src/deployment.lisp b/src/deployment.lisp
index 4aef20f..46dc944 100644
--- a/src/deployment.lisp
+++ b/src/deployment.lisp
@@ -122,35 +122,36 @@ into HOST's propspec cannot be done without either the implicit context
 established by a consfig (specifically, by IN-CONSFIG) or with an explicit
 specification of the SYSTEMS slot of the resultant property application
 specification."
-  ;; make a partial own-copy of HOST so that connections can add new pieces of
-  ;; required prerequisite data; specifically, so that they can request the
-  ;; source code of ASDF systems
-  (let ((*host* (make-instance 'host
-			       :attrs (copy-list (slot-value host 'hostattrs))
-			       :props (slot-value host 'propspec))))
-    (labels
-	((connect (connections)
-	   (destructuring-bind ((type . args) . remaining) connections
-	     ;; implementations of ESTABLISH-CONNECTION which call
-	     ;; CONTINUE-DEPLOY* or CONTINUE-DEPLOY*-PROGRAM return nil to us
-	     (when-let ((*connection*
-			 (apply #'establish-connection type remaining args)))
-	       (if remaining
-		   (connect remaining)
-		   (eval-propspec (slot-value *host* 'propspec)))
-	       (connection-teardown *connection*)))))
-      (connect (loop for connection in (ensure-cons connections)
+  (labels
+      ((connect (connections)
+	 (destructuring-bind ((type . args) . remaining) connections
+	   ;; implementations of ESTABLISH-CONNECTION which call
+	   ;; CONTINUE-DEPLOY* or CONTINUE-DEPLOY*-PROGRAM return nil to us
+	   (when-let ((*connection*
+		       (apply #'establish-connection type remaining args)))
+	     (if remaining
+		 (connect remaining)
+		 (eval-propspec (host-propspec *host*)))
+	     (connection-teardown *connection*)))))
+    ;; make a partial own-copy of HOST so that connections can add new pieces
+    ;; of required prerequisite data; specifically, so that they can request
+    ;; the source code of ASDF systems
+    (let ((*host* (make-instance 'host :props (host-propspec host)
+				       :attrs (copy-list (hostattrs host)))))
+      (connect (normalise-connections connections)))))
+
+(defun normalise-connections (connections)
+  (let ((chain (loop for connection in (ensure-cons connections)
 		     collect (apply #'preprocess-connection-args
-				    (ensure-cons connection)))))))
+				    (ensure-cons connection)))))
+    (if (eq :local (caar chain)) chain (cons '(:local) chain))))
 
-;; we can't just default CONNECTIONS to :LOCAL in the lambda list, because it
-;; is legitimate for callers to explicitly pass nil
 (defun continue-deploy* (remaining-connections)
   "Complete the work of an enclosing call to DEPLOY*.
 
 Used by implementations of ESTABLISH-CONNECTION which need to do something like
 fork(2) and then return to Consfigurator's primary loop in the child."
-  (deploy* (or remaining-connections :local) *host*))
+  (deploy* remaining-connections *host*))
 
 ;; these might need to be special-cased in parsing propspecs, because we
 ;; probably want it to be easy for the user to pass unevaluated propspecs to