Makefile: Allow specifying the path to emacs

Running emacs on macOS, the emacs binary is inside the app bundle, not
on the path, so it's useful to be able to specify it.

diff --git a/Makefile b/Makefile
index 0846ede74235b51df28ef84ab602a9d8959d557c..a2bb127679533f1e82806e0c4d69ea0ee54b0df7 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -14,6 +14,8 @@ SWIPL      ?= swipl
 SWIPLBASE   = $(shell $(SWIPL) --dump-runtime-variables | grep PLBASE   | cut -f 2 -d = | cut -f 1 -d ';')
 SWIPLLIBDIR = $(shell $(SWIPL) --dump-runtime-variables | grep PLLIBDIR | cut -f 2 -d = | cut -f 1 -d ';')
 
+EMACS ?= emacs
+
 TARGET   = $(BASENAME)-module.$(SOEXT)
 OBJECT   = $(BASENAME).o
 SOURCE   = $(BASENAME).c
@@ -42,9 +44,9 @@ clean:
        rm -f $(TARGET) $(OBJECT) $(BASENAME).info $(BASENAME).texi $(BASENAME).html
 
 $(BASENAME).info:: README.org
-       emacs -Q --batch --eval "(require 'ox-texinfo)" \
+       $(EMACS) -Q --batch --eval "(require 'ox-texinfo)" \
                --eval "(with-current-buffer (find-file \"README.org\") (org-export-to-file (quote texinfo) \"$@\" nil nil nil nil nil (quote org-texinfo-compile)))"
 
 check: $(TARGET)
-       emacs --batch --eval '(add-to-list (quote load-path) (expand-file-name "."))' \
+       $(EMACS) --batch --eval '(add-to-list (quote load-path) (expand-file-name "."))' \
                -l ert -l sweep -l sweep-tests.el -f ert-run-tests-batch-and-exit