improved Emscripten support: fixed configure-checks, generate *.js and detect EMCurses

 * Emscripten can be used (theoretically) to build a host-only platform-independant version
   of SciTECO (running under node.js instead of the browser).
 * I ported netbsd-curses with Emscripten for that purpose. Therefore, adaptions for running
   in the browser are restricted to EMcurses now.

4 files changed, 33 insertions, 14 deletions

diff --git a/configure.ac b/configure.ac
index 032ab10..dd4854d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -57,7 +57,6 @@ AX_CXX_COMPILE_STDCXX(11, noext, mandatory)
 AC_PROG_CC
 AC_PROG_CC_C99
 AC_PROG_SED
-AC_PROG_GREP
 AC_PROG_INSTALL
 
 # Mainly because of Scintilla, which depends on
@@ -88,10 +87,18 @@ case $host in
 	;;
 esac
 
-# Detect Clang. Emscripten is based on Clang as well.
-if $CXX --version | $GREP -E "clang|Emscripten" >/dev/null; then
+# Detect Clang (including Emscripten).
+# A particular warning does not cooperate well with our use
+# of the BSD data structures.
+AC_CHECK_DECL(__clang__, [
 	CXXFLAGS="$CXXFLAGS -Wno-mismatched-tags"
-fi
+])
+
+# Changing the EXEEXT on emscripten ensures that we don't
+# need a special Makefile rule to generate Javascript files.
+AC_CHECK_DECL(EMSCRIPTEN, [
+	EXEEXT=.js
+])
 
 AC_CHECK_PROG(DATE, date, date)
 if [[ x$DATE = x ]]; then
@@ -179,7 +186,10 @@ esac
 # Some of this will only be found on glibc,
 # others on FreeBSD/jemalloc.
 AC_CHECK_HEADERS([malloc.h malloc_np.h])
-AC_CHECK_FUNCS([malloc_trim malloc_usable_size])
+AC_CHECK_FUNCS([malloc_trim malloc_usable_size], [
+	# Sometimes the declaration is missing.
+	AC_CHECK_DECLS([malloc_trim])
+])
 
 #
 # Config options
diff --git a/src/cmdline.cpp b/src/cmdline.cpp
index daf1a9b..9262e27 100644
--- a/src/cmdline.cpp
+++ b/src/cmdline.cpp
@@ -47,6 +47,12 @@
 #include "error.h"
 #include "cmdline.h"
 
+extern "C" {
+#if defined(HAVE_MALLOC_TRIM) && !HAVE_DECL_MALLOC_TRIM
+int malloc_trim(size_t pad);
+#endif
+}
+
 namespace SciTECO {
 
 static gchar *filename_complete(const gchar *filename, gchar completed = ' ',
diff --git a/src/interface-curses/interface-curses.cpp b/src/interface-curses/interface-curses.cpp
index 96ce0d4..a06fe30 100644
--- a/src/interface-curses/interface-curses.cpp
+++ b/src/interface-curses/interface-curses.cpp
@@ -89,6 +89,15 @@
 #define A_UNDERLINE 0
 #endif
 
+/**
+ * Whether we're on EMCurses.
+ * Could be replaced with a configure-time check for
+ * PDC_emscripten_set_handler().
+ */
+#if defined(__PDCURSES__) && defined(EMSCRIPTEN)
+#define EMCURSES
+#endif
+
 #ifdef NCURSES_VERSION
 #if defined(G_OS_UNIX) || defined(G_OS_HAIKU)
 /**
@@ -630,7 +639,7 @@ InterfaceCurses::init_interactive(void)
 	cmdline_window = newwin(0, 0, LINES - 1, 0);
 	keypad(cmdline_window, TRUE);
 
-#ifdef EMSCRIPTEN
+#ifdef EMCURSES
         nodelay(cmdline_window, TRUE);
 #endif
 
@@ -1533,7 +1542,7 @@ InterfaceCurses::event_loop_impl(void)
 	wnoutrefresh(cmdline_window);
 	doupdate();
 
-#ifdef EMSCRIPTEN
+#ifdef EMCURSES
 	PDC_emscripten_set_handler(event_loop_iter, TRUE);
 	/*
 	 * We must not block emscripten's main loop,
diff --git a/src/parser.h b/src/parser.h
index f61d335..9255268 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -149,13 +149,7 @@ protected:
 
 	MicroState state;
 
-#ifdef EMSCRIPTEN
-	/* FIXME: Shouldn't be required! */
-	__attribute__((noinline))
-#else
-	inline
-#endif
-	void
+	inline void
 	set(MicroState next)
 	{
 		if (next != state)