 (defun git-rev-parse (rev)
   "Parse a revision name and return its SHA1."
   (git-get-string-sha1
-   (git-call-process-env-string nil "rev-parse" rev)))
+   (git-call-process-string "rev-parse" rev)))
 
 (defun git-config (key)
   "Retrieve the value associated to KEY in the git repository config file."
-  (let ((str (git-call-process-env-string nil "config" key)))
+  (let ((str (git-call-process-string "config" key)))
     (and str (car (split-string str "\n")))))
 
 (defun git-symbolic-ref (ref)
   "Wrapper for the git-symbolic-ref command."
-  (let ((str (git-call-process-env-string nil "symbolic-ref" ref)))
+  (let ((str (git-call-process-string "symbolic-ref" ref)))
     (and str (car (split-string str "\n")))))
 
 (defun git-update-ref (ref newval &optional oldval reason)

  "Build a list of NAME=VALUE strings from a list of environment strings."
  (mapcar (lambda (entry) (concat (car entry) "=" (cdr entry))) env))

(defun git-call-process-env (buffer env &rest args)
  "Wrapper for call-process that sets environment strings."
  (let ((process-environment (append (git-get-env-strings env)
                                     process-environment)))
    (apply #'call-process "git" nil buffer nil args)))

(defun git-call-process-display-error (&rest args)
  "Wrapper for call-process that displays error messages."


(defun git-empty-db-p ()
  "Check if the git db is empty (no commit done yet)."
  (not (eq 0 (git-call-process nil "rev-parse" "--verify" "HEAD"))))

(defun git-get-merge-heads ()
  "Retrieve the merge heads from the MERGE_HEAD file if present."
