1 files changed, 131 insertions, 0 deletions
diff --git a/src/cmd/htmlroff/t17.c b/src/cmd/htmlroff/t17.c
new file mode 100644
index 00000000..2800ec76
--- /dev/null
+++ b/src/cmd/htmlroff/t17.c
@@ -0,0 +1,131 @@
+#include "a.h"
+
+/*
+ * 17.  Environment switching.
+ */
+typedef struct Env Env;
+struct Env
+{
+	int s;
+	int s0;
+	int f;
+	int f0;
+	int fi;
+	int ad;
+	int ce;
+	int v;
+	int v0;
+	int ls;
+	int ls0;
+	int it;
+	/* - ta */
+	/* - tc */
+	/* - lc */
+	/* - ul */
+	/* - cu */
+	/* - cc */
+	/* - c2 */
+	/* - nh */
+	/* - hy */
+	/* - hc */
+	/* - lt */
+	/* - nm */
+	/* - nn */
+	/* - mc */
+};
+
+Env defenv =
+{
+	10,
+	10,
+	1,
+	1,
+	1,
+	1,
+	0,
+	12,
+	12,
+	0,
+	0,
+	0,
+};
+
+Env env[3];
+Env *evstack[20];
+int nevstack;
+
+void
+saveenv(Env *e)
+{
+	e->s = getnr(L(".s"));
+	e->s0 = getnr(L(".s0"));
+	e->f = getnr(L(".f"));
+	e->f0 = getnr(L(".f0"));
+	e->fi = getnr(L(".fi"));
+	e->ad = getnr(L(".ad"));
+	e->ce = getnr(L(".ce"));
+	e->v = getnr(L(".v"));
+	e->v0 = getnr(L(".v0"));
+	e->ls = getnr(L(".ls"));
+	e->ls0 = getnr(L(".ls0"));
+	e->it = getnr(L(".it"));
+}
+
+void
+restoreenv(Env *e)
+{
+	nr(L(".s"), e->s);
+	nr(L(".s0"), e->s0);
+	nr(L(".f"), e->f);
+	nr(L(".f0"), e->f0);
+	nr(L(".fi"), e->fi);
+	nr(L(".ad"), e->ad);
+	nr(L(".ce"), e->ce);
+	nr(L(".v"), e->v);
+	nr(L(".v0"), e->v0);
+	nr(L(".ls"), e->ls);
+	nr(L(".ls0"), e->ls0);
+	nr(L(".it"), e->it);
+
+	nr(L(".ev"), e-env);
+	runmacro1(L("font"));
+}
+
+
+void
+r_ev(int argc, Rune **argv)
+{
+	int i;
+	Env *e;
+	
+	if(argc == 1){
+		if(nevstack <= 0){
+			if(verbose) warn(".ev stack underflow");
+			return;
+		}
+		restoreenv(evstack[--nevstack]);
+		return;
+	}
+	if(nevstack >= nelem(evstack))
+		sysfatal(".ev stack overflow");
+	i = eval(argv[1]);
+	if(i < 0 || i > 2){
+		warn(".ev bad environment %d", i);
+		i = 0;
+	}
+	e = &env[getnr(L(".ev"))];
+	saveenv(e);
+	evstack[nevstack++] = e;
+	restoreenv(&env[i]);
+}
+
+void
+t17init(void)
+{
+	int i;
+	
+	for(i=0; i<nelem(env); i++)
+		env[i] = defenv;
+
+	addreq(L("ev"), r_ev, -1);
+}