From: Nick Bowler <nbowler@draconx.ca>
Date: Fri, 7 Feb 2020 03:26:38 +0000 (-0500)
Subject: Require flex to build the scanner.
X-Git-Url: http://git.draconx.ca/gitweb/gob-dx.git/commitdiff_plain/14f532691ec5161558c80bfbaa81be053d05f0ca

Require flex to build the scanner.

There is not much point in compatibility with various lex incarnations,
since the generated files are distributed and the user does not need
any lex tool to simply build from a tarball.

This additionally avoids a problem with AC_PROG_LEX which can hard-fail
the configure run when the selected lex command is not working, even
if the tool is not needed for the build.  Now, a fatal error will only
be generated if the tool is required at make time.
---

diff --git a/Makefile.am b/Makefile.am
index 7f09957..e8afbc6 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -20,48 +20,72 @@ EXTRA_DIST = COPYING.GPL3 COPYING.generated-code \
              examples/foo-some-interface.gob examples/gtk-button-count.gob \
              examples/my-glade-main.c examples/my-glade.glade \
              examples/my-glade.gob gob2.spec src/generate_treefuncs.pl \
-             src/treefuncs.def src/treefuncs.stamp t/str.gob t/test-fooable.c \
-             t/test-fooable.h t/test.gob
+             src/lexer.l src/lexer.stamp src/treefuncs.def \
+             src/treefuncs.stamp t/str.gob t/test-fooable.c t/test-fooable.h \
+             t/test.gob
 
 CLEANFILES =
 DISTCLEANFILES =
-MAINTAINERCLEANFILES = src/treefuncs.c src/treefuncs.h src/treefuncs.stamp
+MAINTAINERCLEANFILES = src/lexer.c src/lexer.h src/lexer.stamp \
+                       src/treefuncs.c src/treefuncs.h src/treefuncs.stamp
 
 EXTRA_PROGRAMS = parser-rdeps
-parser_rdeps_SOURCES = src/main.c src/lexer.l
+parser_rdeps_SOURCES = src/main.c src/lexer.c
 $(parser_rdeps_OBJECTS): src/parse.h
 
 noinst_HEADERS = src/main.h src/treefuncs.h src/out.h src/util.h src/checks.h
 
 gob2_SOURCES = src/main.c src/main.h src/treefuncs.c src/out.c src/util.c \
-               src/checks.c src/parse.y src/lexer.l
-gob2_LDADD = $(LIBGLIB_LIBS) @LEXLIB@
+               src/checks.c src/parse.y src/lexer.c src/lexer.h
+gob2_LDADD = $(LIBGLIB_LIBS)
 $(gob2_OBJECTS): src/treefuncs.h
 
 man_MANS = doc/gob2.1
 EXTRA_DIST += doc/makehtml.pl
 
-PERL_ERROR = @:; { \
-	  printf '%s: ERROR: perl was not available at configure time.\n' "$@"; \
-	  printf '%s: If perl is installed but was not detected by configure,\n' "$@"; \
-	  printf '%s: consider setting PERL and re-running configure.\n' "$@"; \
-	} 1>&2; false
+FLEX_V   = $(FLEX_V_@AM_V@)
+FLEX_V_  = $(FLEX_V_@AM_DEFAULT_V@)
+FLEX_V_0 = @printf '  %$(DX_ALIGN_V)s %s\n' 'FLEX    ' $<;
+
+TOOL_ERROR = { \
+  echo "ERROR: *** $$tool is missing on your system."; \
+  echo "       *** Because of this, I cannot compile $$toolsrc, but"; \
+  echo "       *** (perhaps because you modified it) the sources appear out"; \
+  echo "       *** of date.  If $$tool is installed but was not detected by"; \
+  echo "       *** configure, consired setting $$toolvar and re-running configure."; \
+  echo "       *** See config.log for more details."; } >&2; false
 
 src/treefuncs.stamp: src/generate_treefuncs.pl src/treefuncs.def
 if !HAVE_PERL
-	$(PERL_ERROR)
+	@tool=perl toolvar=PERL toolsrc=src/treefuncs.def; $(TOOL_ERROR)
 endif
-	$(AM_V_at) $(MKDIR_P) $(@D)
+	$(AM_V_at) $(MKDIR_P) $(@D) && touch $@.tmp
 	$(AM_V_GEN) (cd $(@D) && \
 	  $(PERL) $(abs_srcdir)/src/generate_treefuncs.pl \
 	          $(abs_srcdir)/src/treefuncs.def; )
-	$(AM_V_at) touch $@
+	$(AM_V_at) mv -f $@.tmp $@
+
+.l.c: ;
+.l.stamp:
+if !HAVE_FLEX
+	@tool=flex toolvar=FLEX toolsrc=$<; $(TOOL_ERROR)
+endif
+	$(AM_V_at) touch $@.tmp
+	$(AM_V_at) rm -f $*.h.tmp; mv -f $*.h $*.h.tmp 2>/dev/null; :
+	$(FLEX_V) $(FLEX) -o $*.c --header-file=$*.h $(FLEXFLAGS) $<
+	$(AM_V_at) if cmp $*.h.tmp $*.h >/dev/null 2>&1; \
+	  then mv -f $*.h.tmp $*.h; \
+	  else rm -f $*.h.tmp; fi
+	$(AM_V_at) mv -f $@.tmp $@
 
 .stamp.c:
 	@test -f $@ || { rm -f $<; $(MAKE) $(AM_MAKEFLAGS) $<; }
 .stamp.h:
 	@test -f $@ || { rm -f $<; $(MAKE) $(AM_MAKEFLAGS) $<; }
 
+# Required to prevent the builtin lex rule from superseding ours
+src/lexer.c src/lexer.h: src/lexer.stamp
+
 html-local: doc/gob2.html
 doc/gob2.html: doc/gob2.1
 if !HAVE_PERL
@@ -95,7 +119,7 @@ EXTRA_DIST += common/m4/gob2.m4
 
 git_changelog_start = 2cd951c678998b2b0230c8eb25717ecf0f1dd2db
 dist-hook: generate-changelog
-generate-changelog:
+generate-changelog: unfuck-distdir
 	-: "$${GIT_DIR=$(top_srcdir)/.git}"; \
 	  test -d "$$GIT_DIR" || exit 0; { \
 	    $(PERL) -x $(top_srcdir)/build-aux/gitlog-to-changelog -- \
@@ -107,6 +131,23 @@ generate-changelog:
 	rm -f $(distdir)/ChangeLog.gen
 .PHONY: generate-changelog
 
+# Ensure that any generated headers, which may be left unchanged to improve
+# incremental build performance, are fully up-to-date in the distribution.
+dist-hook: update-headers
+update-headers: unfuck-distdir
+	touch -c $(distdir)/src/lexer.h
+.PHONY: update-headers
+
+# When running "make dist" in a VPATH build with a read-only srcdir, Automake
+# will produce a distribution with all files read-only.  Moreover, the files
+# are read-only in distdir when the dist hooks are run.  This hook will fix
+# up the permission.  All dist hooks that modify files in distdir should list
+# unfuck-distdir as a prerequisite.
+dist-hook: unfuck-distdir
+unfuck-distdir:
+	find '$(distdir)' -type f -exec chmod u+w {} +
+.PHONY: unfuck-distdir
+
 GENERIC_V   = $(GENERIC_V_@AM_V@)
 GENERIC_V_  = $(GENERIC_V_@AM_DEFAULT_V@)
 GENERIC_V_0 = @printf '%2.0s%$(DX_ALIGN_V)s %s\n'
diff --git a/common b/common
index 4705ffd..803e498 160000
--- a/common
+++ b/common
@@ -1 +1 @@
-Subproject commit 4705ffd69e7b7551bab4650f9e49756667be783b
+Subproject commit 803e498e869f88d9daceadf143e3360c17cb7410
diff --git a/configure.ac b/configure.ac
index f3e4b91..b43fc7c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -16,7 +16,6 @@ DX_AUTOMAKE_COMPAT
 
 AC_PROG_CC
 AC_PROG_CXX
-AC_PROG_LEX
 AC_PROG_YACC
 
 AC_ARG_VAR([PERL], [command to execute perl programs])
@@ -25,6 +24,9 @@ AM_CONDITIONAL([HAVE_PERL], [$PERL -e 'my $x = 42; exit $x'; test $? = 42])
 
 LT_INIT
 
+DX_PROG_FLEX([], [have_flex=yes], [have_flex=no])
+AM_CONDITIONAL([HAVE_FLEX], [test x"$have_flex" = x"yes"])
+
 DX_LIB_GLIB2
 
 dnl Dependencies for test suite
diff --git a/src/.gitignore b/src/.gitignore
index 27aec08..89b3329 100644
--- a/src/.gitignore
+++ b/src/.gitignore
@@ -1,4 +1,5 @@
-/lexer.c
+/lexer.[ch]
+/lexer.stamp
 /parse.[ch]
-/treefuncs.stamp
 /treefuncs.[ch]
+/treefuncs.stamp