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Diffstat (limited to 'app/tools/halibut/charset/cp949.c')
-rw-r--r--app/tools/halibut/charset/cp949.c94
1 files changed, 94 insertions, 0 deletions
diff --git a/app/tools/halibut/charset/cp949.c b/app/tools/halibut/charset/cp949.c
new file mode 100644
index 0000000..28cd63a
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+++ b/app/tools/halibut/charset/cp949.c
@@ -0,0 +1,94 @@
+/*
+ * cp949.c - CP949 / KS_C_5601_1987 multibyte encoding
+ */
+
+#ifndef ENUM_CHARSETS
+
+#include "charset.h"
+#include "internal.h"
+
+/*
+ * CP949 has no associated data, so `charset' may be ignored.
+ */
+
+static void read_cp949(charset_spec const *charset, long int input_chr,
+ charset_state *state,
+ void (*emit)(void *ctx, long int output), void *emitctx)
+{
+ UNUSEDARG(charset);
+
+ /*
+ * For reading CP949, state->s0 simply contains the single
+ * stored lead byte when we are half way through a double-byte
+ * character, or 0 if we aren't.
+ */
+
+ if (state->s0 == 0) {
+ if (input_chr >= 0x81 && input_chr <= 0xFE) {
+ /*
+ * Lead byte. Just store it.
+ */
+ state->s0 = input_chr;
+ } else {
+ /*
+ * Anything else we pass straight through unchanged.
+ */
+ emit(emitctx, input_chr);
+ }
+ } else {
+ /*
+ * We have a stored lead byte. We expect a valid followup
+ * byte.
+ */
+ if ((input_chr >= 0x40 && input_chr <= 0xFF)) {
+ emit(emitctx, cp949_to_unicode(state->s0 - 0x80,
+ input_chr - 0x40));
+ } else {
+ emit(emitctx, ERROR);
+ }
+ state->s0 = 0;
+ }
+}
+
+/*
+ * CP949 is a stateless multi-byte encoding (in the sense that just
+ * after any character has been completed, the state is always the
+ * same); hence when writing it, there is no need to use the
+ * charset_state.
+ */
+
+static int write_cp949(charset_spec const *charset, long int input_chr,
+ charset_state *state,
+ void (*emit)(void *ctx, long int output),
+ void *emitctx)
+{
+ UNUSEDARG(charset);
+ UNUSEDARG(state);
+
+ if (input_chr == -1)
+ return TRUE; /* stateless; no cleanup required */
+
+ if (input_chr < 0x80) {
+ emit(emitctx, input_chr);
+ return TRUE;
+ } else {
+ int r, c;
+ if (unicode_to_cp949(input_chr, &r, &c)) {
+ emit(emitctx, r + 0x80);
+ emit(emitctx, c + 0x40);
+ return TRUE;
+ } else {
+ return FALSE;
+ }
+ }
+}
+
+const charset_spec charset_CS_CP949 = {
+ CS_CP949, read_cp949, write_cp949, NULL
+};
+
+#else /* ENUM_CHARSETS */
+
+ENUM_CHARSET(CS_CP949)
+
+#endif /* ENUM_CHARSETS */