add

src/cmd/htmlroff/t4.c

@@ -0,0 +1,142 @@
+#include "a.h"
+
+/*
+ * 4 - Text filling, centering, and adjusting.  
+ * 	"\ " - unbreakable space
+ * 	.n register - length of last line
+ *	nl register - text baseline position on this page
+ *	.h register - baseline high water mark
+ *	.k register - current horizontal output position
+ *	\p - cause break at end of word, justify
+ *	\& - non-printing zero-width filler
+ *	tr - output translation
+ *	\c - break (but don't) input line in .nf mode
+ *	\c - break (but don't) word in .fi mode
+ */
+
+int
+e_space(void)
+{
+	return 0xA0;	/* non-breaking space */
+}
+
+int
+e_amp(void)
+{
+	return Uempty;
+}
+
+int
+e_c(void)
+{
+	getrune();
+	bol = 1;
+	return 0;
+}
+
+void
+r_br(int argc, Rune **argv)
+{
+	USED(argc);
+	USED(argv);
+	br();
+}
+
+/* fill mode on */
+void
+r_fi(int argc, Rune **argv)
+{
+	USED(argc);
+	USED(argv);
+	nr(L(".fi"), 1);
+// warn(".fi");
+}
+
+/* no-fill mode */
+void
+r_nf(int argc, Rune **argv)
+{
+	USED(argc);
+	USED(argv);
+	nr(L(".fi"), 0);
+}
+
+/* adjust */
+void
+r_ad(int argc, Rune **argv)
+{
+	int c, n;
+	
+	nr(L(".j"), getnr(L(".j"))|1);
+	if(argc < 2)
+		return;
+	c = argv[1][0];
+	switch(c){
+	default:
+		fprint(2, "%L: bad adjust %C\n", c);
+		return;
+	case 'r':
+		n = 2*2|1;
+		break;
+	case 'l':
+		n = 0;
+		break;
+	case 'c':
+		n = 1*2|1;
+		break;
+	case 'b':
+	case 'n':
+		n = 0*2|1;
+		break;
+	case '0':
+	case '1':
+	case '2':
+	case '3':
+	case '4':
+	case '5':
+		n = c-'0';
+		break;
+	}
+	nr(L(".j"), n);
+}
+
+/* no adjust */
+void
+r_na(int argc, Rune **argv)
+{
+	USED(argc);
+	USED(argv);
+
+	nr(L(".j"), getnr(L(".j"))&~1);
+}
+
+/* center next N lines */
+void
+r_ce(int argc, Rune **argv)
+{
+	if(argc < 2)
+		nr(L(".ce"), 1);
+	else
+		nr(L(".ce"), eval(argv[1]));
+	/* XXX set trap */
+}
+
+void
+t4init(void)
+{
+	nr(L(".fi"), 1);
+	nr(L(".j"), 1);
+
+	addreq(L("br"), r_br, 0);
+	addreq(L("fi"), r_fi, 0);
+	addreq(L("nf"), r_nf, 0);
+	addreq(L("ad"), r_ad, -1);
+	addreq(L("na"), r_na, 0);
+	addreq(L("ce"), r_ce, -1);
+	
+	addesc(' ', e_space, 0);
+	addesc('p', e_warn, 0);
+	addesc('&', e_amp, 0);
+	addesc('c', e_c, 0);
+}
+