Attempt to convert output to locale charset from UTF-8

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Makefile.am

@@ -16,7 +16,7 @@ AM_CPPFLAGS = -DLOCALEDIR="\"$(localedir)\""
 
 openconnect_SOURCES = xml.c main.c
 openconnect_CFLAGS = $(AM_CFLAGS) $(SSL_CFLAGS) $(DTLS_SSL_CFLAGS) $(LIBXML2_CFLAGS) $(LIBPROXY_CFLAGS) $(ZLIB_CFLAGS) $(LIBSTOKEN_CFLAGS) $(LIBOATH_CFLAGS) $(GSSAPI_CFLAGS)
-openconnect_LDADD = libopenconnect.la $(LIBXML2_LIBS) $(LIBPROXY_LIBS) $(LIBINTL)
+openconnect_LDADD = libopenconnect.la $(LIBXML2_LIBS) $(LIBPROXY_LIBS) $(LIBINTL) $(LIBICONV)
 
 library_srcs = ssl.c http.c auth.c library.c compat.c dtls.c cstp.c \
 	       mainloop.c script.c ntlm.c digest.c

configure.ac

@@ -179,6 +179,32 @@ AC_CHECK_FUNCS(setenv unsetenv)
 AC_ENABLE_SHARED
 AC_DISABLE_STATIC
 
+have_iconv=no
+LIBICONV=
+AC_MSG_CHECKING([for iconv support])
+AC_LINK_IFELSE([AC_LANG_PROGRAM([
+    #include <iconv.h>],[
+    iconv_t ic = iconv_open("","");])],
+    [AC_MSG_RESULT(yes)
+     have_iconv=yes],
+    [oldLIBS="$LIBS"
+     LIBS="$LIBS -liconv"
+    AC_LINK_IFELSE([AC_LANG_PROGRAM([
+      #include <iconv.h>],[
+      iconv_t ic = iconv_open("","");])],
+      [AC_MSG_RESULT(yes (with -liconv))
+       have_iconv=yes
+       LIBICONV=-liconv],
+      [AC_MSG_RESULT(no)])
+       LIBS="$oldLIBS"])
+
+if test "$have_iconv" = "yes"; then
+   AC_SUBST(LIBICONV)
+   AC_DEFINE(HAVE_ICONV, 1, [Have iconv() function])
+fi
+
+AC_CHECK_FUNC(nl_langinfo, [AC_DEFINE(HAVE_NL_LANGINFO, 1, [Have nl_langinfo() function])], [])
+
 AC_ARG_ENABLE([nls],
 	[  --disable-nls           do not use Native Language Support],
 	[USE_NLS=$enableval], [USE_NLS=yes])

main.c

@@ -245,6 +245,79 @@ static struct option long_options[] = {
 	OPTION(NULL, 0, 0)
 };
 
+#if defined(HAVE_NL_LANGINFO) && defined(HAVE_ICONV)
+#include <iconv.h>
+#include <langinfo.h>
+
+static const char *legacy_charset;
+
+static int vfprintf_utf8(FILE *f, const char *fmt, va_list args)
+{
+	char *utf8_str;
+	iconv_t ic;
+	int ret;
+	char outbuf[80];
+	char *ic_in, *ic_out;
+	size_t insize, outsize;
+
+	if (!legacy_charset)
+		return vfprintf(f, fmt, args);
+
+	ret = vasprintf(&utf8_str, fmt, args);
+	if (ret < 0)
+		return -1;
+
+	ic = iconv_open(legacy_charset, "UTF-8");
+	if (ic == (iconv_t) -1) {
+		/* Better than nothing... */
+		ret = fprintf(f, "%s", utf8_str);
+		free(utf8_str);
+		return ret;
+	}
+
+	ic_in = utf8_str;
+	insize = strlen(utf8_str);
+	ret = 0;
+
+	while (insize) {
+		ic_out = outbuf;
+		outsize = sizeof(outbuf) - 1;
+
+		if (iconv(ic, &ic_in, &insize, &ic_out, &outsize) == (size_t)-1) {
+			if (errno == EILSEQ) {
+				do {
+					ic_in++;
+					insize--;
+				} while (insize && (ic_in[0] & 0xc0) == 0x80);
+				ic_out[0] = '?';
+				outsize--;
+			} else if (errno != E2BIG)
+				break;
+		}
+		ret += fwrite(outbuf, 1, sizeof(outbuf) - 1 - outsize, f);
+	}
+
+	iconv_close(ic);
+
+	return ret;
+}
+
+static int fprintf_utf8(FILE *f, const char *fmt, ...)
+{
+	va_list args;
+	int ret;
+
+	va_start(args, fmt);
+	ret = vfprintf_utf8(f, fmt, args);
+	va_end(args);
+
+	return ret;
+}
+
+#define fprintf fprintf_utf8
+#define vfprintf vfprintf_utf8
+#endif
+
 static void helpmessage(void)
 {
 	printf(_("For assistance with OpenConnect, please see the web page at\n"
@@ -665,6 +738,11 @@ int main(int argc, char **argv)
 	bindtextdomain("openconnect", LOCALEDIR);
 	setlocale(LC_ALL, "");
 #endif
+#if defined(HAVE_NL_LANGINFO) && defined(HAVE_ICONV)
+	legacy_charset = nl_langinfo(CODESET);
+	if (legacy_charset && !strcmp(legacy_charset, "UTF-8"))
+		legacy_charset = NULL;
+#endif
 
 	if (strcmp(openconnect_version_str, openconnect_binary_version)) {
 		fprintf(stderr, _("WARNING: This version of openconnect is %s but\n"