Add a source code sanity check.

Makefile.am

@@ -1,5 +1,5 @@
 
-SUBDIRS = src tools fonts doc
+SUBDIRS = src tools fonts doc test
 DIST_SUBDIRS = $(SUBDIRS)
 
 EXTRA_DIST = bootstrap

configure.ac

@@ -78,5 +78,6 @@ AC_OUTPUT([
   tools/Makefile
   fonts/Makefile
   doc/Makefile
+  test/Makefile
 ])
 

src/Makefile.am

@@ -10,3 +10,5 @@ toilet_CPPFLAGS = -DFONTDIR=\"$(datadir)/figlet\"
 toilet_CFLAGS = @CACA_CFLAGS@
 toilet_LDADD = @CACA_LIBS@ @GETOPT_LIBS@ @ZLIB_LIBS@
 
+echo-sources: ; echo $(SOURCES)
+

test/Makefile.am

@@ -0,0 +1,6 @@
+# $Id$
+
+EXTRA_DIST = check-build
+
+TESTS = check-build
+

test/check-build

@@ -0,0 +1,34 @@
+#!/bin/sh
+
+ret=0
+
+#
+# Check that we have no tabs or trailing spaces in the source code
+#
+failure=0
+for dir in src tools; do
+  pushd ../$dir >/dev/null
+  for x in $(make echo-sources); do
+    if grep '[[:space:]]$' "$x" >/dev/null 2>&1; then
+      echo "error: $dir/$x contains trailing spaces"
+      failure=1
+    fi
+    if grep '	' "$x" >/dev/null 2>&1; then
+      echo "error: $dir/$x contains tabs"
+      failure=1
+    fi
+  done
+  popd >/dev/null
+done
+if test "$failure" != "0"; then
+  ret=1
+else
+  echo "0 errors in source code"
+fi
+
+if test "$ret" != "0"; then
+  exit 1
+fi
+
+exit 0
+

tools/Makefile.am

@@ -6,3 +6,5 @@ caca2tlf_SOURCES = caca2tlf.c
 caca2tlf_CFLAGS = @CACA_CFLAGS@
 caca2tlf_LDADD = @CACA_LIBS@
 
+echo-sources: ; echo $(SOURCES)
+