1 files changed, 82 insertions, 0 deletions
diff --git a/app/tools/halibut/charset/fromucs.c b/app/tools/halibut/charset/fromucs.c
new file mode 100644
index 0000000..8090c19
--- /dev/null
+++ b/app/tools/halibut/charset/fromucs.c
@@ -0,0 +1,82 @@
+/*
+ * fromucs.c - convert Unicode to other character sets.
+ */
+
+#include "charset.h"
+#include "internal.h"
+
+struct charset_emit_param {
+    char *output;
+    int outlen;
+    int stopped;
+};
+
+static void charset_emit(void *ctx, long int output)
+{
+    struct charset_emit_param *param = (struct charset_emit_param *)ctx;
+
+    if (param->outlen > 0) {
+	*param->output++ = output;
+	param->outlen--;
+    } else {
+	param->stopped = 1;
+    }
+}
+
+int charset_from_unicode(const wchar_t **input, int *inlen,
+			 char *output, int outlen,
+			 int charset, charset_state *state, int *error)
+{
+    charset_spec const *spec = charset_find_spec(charset);
+    charset_state localstate = CHARSET_INIT_STATE;
+    struct charset_emit_param param;
+    int locallen;
+
+    if (!input) {
+	locallen = 1;
+	inlen = &locallen;
+    }
+
+    param.output = output;
+    param.outlen = outlen;
+    param.stopped = 0;
+
+    if (state)
+	localstate = *state;	       /* structure copy */
+    if (error)
+	*error = FALSE;
+
+    while (*inlen > 0) {
+	int lenbefore = param.output - output;
+	int ret;
+
+	if (input)
+	    ret = spec->write(spec, **input, &localstate,
+			      charset_emit, &param);
+	else
+	    ret = spec->write(spec, -1, &localstate, charset_emit, &param);
+	if (error && !ret) {
+	    /*
+	     * We have hit a difficult character, which the user
+	     * wants to know about. Leave now.
+	     */
+	    *error = TRUE;
+	    return lenbefore;
+	}
+	if (param.stopped) {
+	    /*
+	     * The emit function has _tried_ to output some
+	     * characters, but ran up against the end of the
+	     * buffer. Leave immediately, and return what happened
+	     * _before_ attempting to process this character.
+	     */
+	    return lenbefore;
+	}
+	if (state)
+	    *state = localstate;       /* structure copy */
+	if (input)
+	    (*input)++;
+	(*inlen)--;
+    }
+    return param.output - output;
+}