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!

1 files changed, 121 insertions, 0 deletions

diff --git a/Modules/cjkcodecs/_shift_jis.c b/Modules/cjkcodecs/_shift_jis.c
new file mode 100644
index 0000000..0bdee3f
--- /dev/null
+++ b/Modules/cjkcodecs/_shift_jis.c
@@ -0,0 +1,121 @@
+/*
+ * _shift_jis.c: the SHIFT-JIS codec
+ *
+ * Written by Hye-Shik Chang <perky@FreeBSD.org>
+ * $CJKCodecs: _shift_jis.c,v 1.4 2003/12/31 05:46:55 perky Exp $
+ */
+
+#include "codeccommon.h"
+#include "alg_jisx0201.h"
+
+ENCMAP(jisxcommon)
+DECMAP(jisx0208)
+
+ENCODER(shift_jis)
+{
+    while (inleft > 0) {
+        Py_UNICODE       c = IN1;
+        DBCHAR           code;
+        unsigned char    c1, c2;
+
+#ifdef STRICT_BUILD
+        JISX0201_R_ENCODE(c, code)
+#else
+        if (c < 0x80) code = c;
+        else if (c == 0x00a5) code = 0x5c; /* YEN SIGN */
+        else if (c == 0x203e) code = 0x7e; /* OVERLINE */
+#endif
+        else JISX0201_K_ENCODE(c, code)
+        else UCS4INVALID(c)
+        else code = NOCHAR;
+
+        if (code < 0x80 || (code >= 0xa1 && code <= 0xdf)) {
+            RESERVE_OUTBUF(1)
+
+            OUT1(code)
+            NEXT(1, 1)
+            continue;
+        }
+
+        RESERVE_OUTBUF(2)
+
+        if (code == NOCHAR) {
+            TRYMAP_ENC(jisxcommon, code, c);
+#ifndef STRICT_BUILD
+            else if (c == 0xff3c)
+                code = 0x2140; /* FULL-WIDTH REVERSE SOLIDUS */
+#endif
+            else
+                return 1;
+
+            if (code & 0x8000) /* MSB set: JIS X 0212 */
+                return 1;
+        }
+
+        c1 = code >> 8;
+        c2 = code & 0xff;
+        c2 = (((c1 - 0x21) & 1) ? 0x5e : 0) + (c2 - 0x21);
+        c1 = (c1 - 0x21) >> 1;
+        OUT1(c1 < 0x1f ? c1 + 0x81 : c1 + 0xc1)
+        OUT2(c2 < 0x3f ? c2 + 0x40 : c2 + 0x41)
+        NEXT(1, 2)
+    }
+
+    return 0;
+}
+
+DECODER(shift_jis)
+{
+    while (inleft > 0) {
+        unsigned char    c = IN1;
+
+        RESERVE_OUTBUF(1)
+
+#ifdef STRICT_BUILD
+        JISX0201_R_DECODE(c, **outbuf)
+#else
+        if (c < 0x80) **outbuf = c;
+#endif
+        else JISX0201_K_DECODE(c, **outbuf)
+        else if ((c >= 0x81 && c <= 0x9f) || (c >= 0xe0 && c <= 0xea)) {
+            unsigned char    c1, c2;
+
+            RESERVE_INBUF(2)
+            c2 = IN2;
+            if (c2 < 0x40 || (c2 > 0x7e && c2 < 0x80) || c2 > 0xfc)
+                return 2;
+
+            c1 = (c < 0xe0 ? c - 0x81 : c - 0xc1);
+            c2 = (c2 < 0x80 ? c2 - 0x40 : c2 - 0x41);
+            c1 = (2 * c1 + (c2 < 0x5e ? 0 : 1) + 0x21);
+            c2 = (c2 < 0x5e ? c2 : c2 - 0x5e) + 0x21;
+
+#ifndef STRICT_BUILD
+            if (c1 == 0x21 && c2 == 0x40) {
+                /* FULL-WIDTH REVERSE SOLIDUS */
+                OUT1(0xff3c)
+                NEXT(2, 1)
+                continue;
+            }
+#endif
+            TRYMAP_DEC(jisx0208, **outbuf, c1, c2) {
+                NEXT(2, 1)
+                continue;
+            } else
+                return 2;
+        } else
+            return 2;
+
+        NEXT(1, 1) /* JIS X 0201 */
+    }
+
+    return 0;
+}
+
+#include "codecentry.h"
+BEGIN_CODEC_REGISTRY(shift_jis)
+    MAPOPEN(ja_JP)
+        IMPORTMAP_DEC(jisx0208)
+        IMPORTMAP_ENC(jisxcommon)
+    MAPCLOSE()
+END_CODEC_REGISTRY(shift_jis)