Add CJK codecs support as discussed on python-dev. (SF #873597)
Several style fixes are suggested by Martin v. Loewis and
Marc-Andre Lemburg. Thanks!
diff --git a/Modules/cjkcodecs/_gbk.c b/Modules/cjkcodecs/_gbk.c
new file mode 100644
index 0000000..b5d058a
--- /dev/null
+++ b/Modules/cjkcodecs/_gbk.c
@@ -0,0 +1,78 @@
+/*
+ * _gbk.c: the GBK codec
+ *
+ * Written by Hye-Shik Chang <perky@FreeBSD.org>
+ * $CJKCodecs: _gbk.c,v 1.2 2003/12/31 05:46:55 perky Exp $
+ */
+
+#include "codeccommon.h"
+#include "tweak_gbk.h"
+
+ENCMAP(gbcommon)
+DECMAP(gb2312)
+DECMAP(gbkext)
+
+ENCODER(gbk)
+{
+ while (inleft > 0) {
+ Py_UNICODE c = IN1;
+ DBCHAR code;
+
+ if (c < 0x80) {
+ WRITE1(c)
+ NEXT(1, 1)
+ continue;
+ }
+ UCS4INVALID(c)
+
+ RESERVE_OUTBUF(2)
+
+ GBK_PREENCODE(c, code)
+ else TRYMAP_ENC(gbcommon, code, c);
+ else return 1;
+
+ OUT1((code >> 8) | 0x80)
+ if (code & 0x8000)
+ OUT2((code & 0xFF)) /* MSB set: GBK */
+ else
+ OUT2((code & 0xFF) | 0x80) /* MSB unset: GB2312 */
+ NEXT(1, 2)
+ }
+
+ return 0;
+}
+
+DECODER(gbk)
+{
+ while (inleft > 0) {
+ unsigned char c = IN1;
+
+ RESERVE_OUTBUF(1)
+
+ if (c < 0x80) {
+ OUT1(c)
+ NEXT(1, 1)
+ continue;
+ }
+
+ RESERVE_INBUF(2)
+
+ GBK_PREDECODE(c, IN2, **outbuf)
+ else TRYMAP_DEC(gb2312, **outbuf, c ^ 0x80, IN2 ^ 0x80);
+ else TRYMAP_DEC(gbkext, **outbuf, c, IN2);
+ else return 2;
+
+ NEXT(2, 1)
+ }
+
+ return 0;
+}
+
+#include "codecentry.h"
+BEGIN_CODEC_REGISTRY(gbk)
+ MAPOPEN(zh_CN)
+ IMPORTMAP_DEC(gb2312)
+ IMPORTMAP_DEC(gbkext)
+ IMPORTMAP_ENC(gbcommon)
+ MAPCLOSE()
+END_CODEC_REGISTRY(gbk)