1 files changed, 165 insertions, 0 deletions
diff --git a/src/cmd/tcs/conv_big5.c b/src/cmd/tcs/conv_big5.c
new file mode 100644
index 00000000..d81c8717
--- /dev/null
+++ b/src/cmd/tcs/conv_big5.c
@@ -0,0 +1,165 @@
+#ifdef	PLAN9
+#include	<u.h>
+#include	<libc.h>
+#include	<bio.h>
+#else
+#include	<stdio.h>
+#include	<unistd.h>
+#include	"plan9.h"
+#endif
+#include	"hdr.h"
+#include	"conv.h"
+#include	"big5.h"
+
+/*
+	a state machine for interpreting big5 (hk format).
+*/
+void
+big5proc(int c, Rune **r, long input_loc)
+{
+	static enum { state0, state1 } state = state0;
+	static int lastc;
+	long n, ch, f, cold = c;
+
+	switch(state)
+	{
+	case state0:	/* idle state */
+		if(c < 0)
+			return;
+		if(c >= 0xA1){
+			lastc = c;
+			state = state1;
+			return;
+		}
+		if(c == 26)
+			c = '\n';
+		emit(c);
+		return;
+
+	case state1:	/* seen a font spec */
+		if(c >= 64 && c <= 126)
+			c -= 64;
+		else if(c >= 161 && c <= 254)
+			c = c-161 + 63;
+		else {
+			nerrors++;
+			if(squawk)
+				EPR "%s: bad big5 glyph (from 0x%x,0x%lx) near byte %ld in %s\n",
+					argv0, lastc, cold, input_loc, file);
+			if(!clean)
+				emit(BADMAP);
+			state = state0;
+			return;
+		}
+		if(lastc >= 161 && lastc <= 254)
+			f = lastc - 161;
+		else {
+			nerrors++;
+			if(squawk)
+				EPR "%s: bad big5 font %d (from 0x%x,0x%lx) near byte %ld in %s\n",
+					argv0, lastc-161, lastc, cold, input_loc, file);
+			if(!clean)
+				emit(BADMAP);
+			state = state0;
+			return;
+		}
+		n = f*BIG5FONT + c;
+		if(n < BIG5MAX)
+			ch = tabbig5[n];
+		else
+			ch = -1;
+		if(ch < 0){
+			nerrors++;
+			if(squawk)
+				EPR "%s: unknown big5 %ld (from 0x%x,0x%lx) near byte %ld in %s\n",
+					argv0, n, lastc, cold, input_loc, file);
+			if(!clean)
+				emit(BADMAP);
+		} else
+			emit(ch);
+		state = state0;
+	}
+}
+
+void
+big5_in(int fd, long *notused, struct convert *out)
+{
+	Rune ob[N];
+	Rune *r, *re;
+	uchar ibuf[N];
+	int n, i;
+	long nin;
+
+	USED(notused);
+	r = ob;
+	re = ob+N-3;
+	nin = 0;
+	while((n = read(fd, ibuf, sizeof ibuf)) > 0){
+		for(i = 0; i < n; i++){
+			big5proc(ibuf[i], &r, nin++);
+			if(r >= re){
+				OUT(out, ob, r-ob);
+				r = ob;
+			}
+		}
+		if(r > ob){
+			OUT(out, ob, r-ob);
+			r = ob;
+		}
+	}
+	big5proc(-1, &r, nin);
+	if(r > ob)
+		OUT(out, ob, r-ob);
+}
+
+void
+big5_out(Rune *base, int n, long *notused)
+{
+	char *p;
+	int i;
+	Rune r;
+	static int first = 1;
+
+	USED(notused);
+	if(first){
+		first = 0;
+		for(i = 0; i < NRUNE; i++)
+			tab[i] = -1;
+		for(i = 0; i < BIG5MAX; i++)
+			if(tabbig5[i] != -1)
+				tab[tabbig5[i]] = i;
+	}
+	nrunes += n;
+	p = obuf;
+	for(i = 0; i < n; i++){
+		r = base[i];
+		if(r < 128)
+			*p++ = r;
+		else {
+			if(tab[r] != -1){
+				r = tab[r];
+				if(r >= BIG5MAX){
+					*p++ = 0xA1;
+					*p++ = r-BIG5MAX;
+					continue;
+				} else {
+					*p++ = 0xA1 + (r/BIG5FONT);
+					r = r%BIG5FONT;
+					if(r <= 62) r += 64;
+					else r += 0xA1-63;
+					*p++ = r;
+					continue;
+				}
+			}
+			if(squawk)
+				EPR "%s: rune 0x%x not in output cs\n", argv0, r);
+			nerrors++;
+			if(clean)
+				continue;
+			*p++ = BYTEBADMAP;
+		}
+	}
+	noutput += p-obuf;
+	if(p > obuf)
+		write(1, obuf, p-obuf);
+}