(sh-get-indent-info): Only indent a continuation line if SPC or TAB precedes \.

(sh-get-indent-info): Simplify.
(sh-mark-init, sh-learn-buffer-indent, sh-add-completer): with-current-buffer.

etc/NEWS

@@ -2181,6 +2181,9 @@ line is left untouched.
 The function `c-toggle-syntactic-indentation' can be used to toggle
 syntactic indentation.
 
+** In sh-script, a continuation line is only indented if the backslash was
+preceded by a SPC or a TAB.
+	
 ---
 ** Perl mode has a new variable `perl-indent-continued-arguments'.
 

lisp/progmodes/sh-script.el

@@ -2033,11 +2033,20 @@ STRING	     This is ignored for the purposes of calculating
 	;; Continuation lines are handled specially
 	(if (sh-this-is-a-continuation)
 	    (progn
-	      ;; We assume the line being continued is already
-	      ;; properly indented...
-	      ;; (setq prev-line-end (sh-prev-line))
-	      (setq align-point (sh-prev-line nil))
-	      (setq result (list '(+ sh-indent-for-continuation)))
+              (setq result
+                    (if (save-excursion
+                          (beginning-of-line)
+                          (not (memq (char-before (- (point) 2)) '(?\s ?\t))))
+                        ;; By convention, if the continuation \ is not
+                        ;; preceded by a SPC or a TAB it means that the line
+                        ;; is cut at a place where spaces cannot be freely
+                        ;; added/removed.  I.e. do not indent the line.
+                        (list '(= nil))
+                      ;; We assume the line being continued is already
+                      ;; properly indented...
+                      ;; (setq prev-line-end (sh-prev-line))
+                      (setq align-point (sh-prev-line nil))
+                      (list '(+ sh-indent-for-continuation))))
 	      (setq have-result t))
 	  (beginning-of-line)
 	  (skip-chars-forward " \t")
@@ -2130,10 +2139,9 @@ STRING	     This is ignored for the purposes of calculating
       (sh-debug "result is now: %s" result)
 
       (or result
-	  (if prev-line-end
-	      (setq result (list (list t prev-line-end)))
-	    (setq result (list (list '= 'sh-first-lines-indent)))
-	    ))
+	  (setq result (list (if prev-line-end
+                                 (list t prev-line-end)
+                               (list '= 'sh-first-lines-indent)))))
 
       (if (eq result t)
 	  (setq result nil))
@@ -2695,11 +2703,9 @@ unless optional argument ARG (the prefix when interactive) is non-nil."
 
 (defun sh-mark-init (buffer)
   "Initialize a BUFFER to be used by `sh-mark-line'."
-  (save-excursion
-    (set-buffer (get-buffer-create buffer))
+  (with-current-buffer (get-buffer-create buffer)
     (erase-buffer)
-    (occur-mode)
-    ))
+    (occur-mode)))
 
 
 (defun sh-mark-line (message point buffer &optional add-linenum occur-point)
@@ -2972,8 +2978,7 @@ This command can often take a long time to run."
 	  (let ((var (car learned-var)))
 	    (sh-mark-line (format "  %s %s" var (symbol-value var))
 			  (nth 2 learned-var) out-buffer)))
-	(save-excursion
-	  (set-buffer out-buffer)
+	(with-current-buffer out-buffer
 	  (goto-char (point-min))
 	  (insert
 	   (format "Indentation values for buffer %s.\n" name)
@@ -3244,8 +3249,7 @@ nil means to return the best completion of STRING, or nil if there is none.
 t means to return a list of all possible completions of STRING.
 `lambda' means to return t if STRING is a valid completion as it stands."
   (let ((sh-shell-variables
-	 (save-excursion
-	   (set-buffer sh-add-buffer)
+	 (with-current-buffer sh-add-buffer
 	   (or sh-shell-variables-initialized
 	       (sh-shell-initialize-variables))
 	   (nconc (mapcar (lambda (var)