add

src/cmd/htmlroff/char.c

@@ -0,0 +1,116 @@
+#include "a.h"
+
+/*
+ * Translate Unicode to HTML by asking tcs(1).
+ * This way we don't have yet another table.
+ */
+Rune*
+rune2html(Rune r)
+{
+	static Biobuf b;
+	static int fd = -1;
+	static Rune **tcscache[256];
+	int p[2];
+	char *q;
+	
+	if(r == '\n')
+		return L("\n");
+
+	if(tcscache[r>>8] && tcscache[r>>8][r&0xFF])
+		return tcscache[r>>8][r&0xFF];
+
+	if(fd < 0){
+		if(pipe(p) < 0)
+			sysfatal("pipe: %r");
+		switch(fork()){
+		case -1:
+			sysfatal("fork: %r");
+		case 0:
+			dup(p[0], 0);
+			dup(p[0], 1);
+			close(p[1]);
+			execl("tcs", "tcs", "-t", "html", nil);
+			_exits(0);
+		default:
+			close(p[0]);
+			fd = p[1];
+			Binit(&b, fd, OREAD);
+			break;
+		}
+	}
+	fprint(fd, "%C\n", r);
+	q = Brdline(&b, '\n');
+	if(q == nil)
+		sysfatal("tcs: early eof");
+	q[Blinelen(&b)-1] = 0;
+	if(tcscache[r>>8] == nil)
+		tcscache[r>>8] = emalloc(256*sizeof tcscache[0][0]);
+	tcscache[r>>8][r&0xFF] = erunesmprint("%s", q);
+	return tcscache[r>>8][r&0xFF];
+}
+
+/*
+ * Translate troff to Unicode by looking in troff's utfmap.
+ * This way we don't have yet another hard-coded table.
+ */
+typedef struct Trtab Trtab;
+struct Trtab
+{
+	char t[3];
+	Rune r;
+};
+
+static Trtab trtab[200];
+int ntrtab;
+
+static Trtab trinit[] =
+{
+	"pl",		Upl,
+	"eq",	Ueq,
+	"em",	0x2014,
+	"en",	0x2013,
+	"mi",	Umi,
+	"fm",	0x2032,
+};
+
+Rune
+troff2rune(Rune *rs)
+{
+	char *file, *f[10], *p, s[3];
+	int i, nf;
+	Biobuf *b;
+	
+	if(rs[0] >= Runeself || rs[1] >= Runeself)
+		return Runeerror;
+	s[0] = rs[0];
+	s[1] = rs[1];
+	s[2] = 0;
+	if(ntrtab == 0){
+		for(i=0; i<nelem(trinit) && ntrtab < nelem(trtab); i++){
+			trtab[ntrtab] = trinit[i];
+			ntrtab++;
+		}
+		file = "/sys/lib/troff/font/devutf/utfmap";
+		if((b = Bopen(file, OREAD)) == nil)
+			sysfatal("open %s: %r", file);
+		while((p = Brdline(b, '\n')) != nil){
+			p[Blinelen(b)-1] = 0;
+			nf = getfields(p, f, nelem(f), 0, "\t");
+			for(i=0; i+2<=nf && ntrtab<nelem(trtab); i+=2){
+				chartorune(&trtab[ntrtab].r, f[i]);
+				memmove(trtab[ntrtab].t, f[i+1], 2);
+				ntrtab++;
+			}
+		}
+		Bterm(b);
+		
+		if(ntrtab >= nelem(trtab))
+			fprint(2, "%s: trtab too small\n", argv0);
+	}
+	
+	for(i=0; i<ntrtab; i++)
+		if(strcmp(s, trtab[i].t) == 0)
+			return trtab[i].r;
+	return Runeerror;
+}
+