Enable NLS catalog of csh(1).

The tcsh 6.14 uses libiconv to convert catalogs to appropriate charset
dynamically.  However, we don't have libiconv in our tree.  So, I made
some hack to load libiconv dynamically.  If libiconv is available, you
can use catalogs for more locales than the locales which catalog is
actually installed.
To use this feature, you need to symlink catalogs to appropriate
locales.  You can do this by installing ports/shells/tcsh_nls.

Reviewed by:	arch (no objection)
MFC after:	1 week

1 files changed, 69 insertions, 0 deletions

diff --git a/bin/csh/iconv_stub.c b/bin/csh/iconv_stub.c
new file mode 100644
index 0000000..6bbbbb0
--- /dev/null
+++ b/bin/csh/iconv_stub.c
@@ -0,0 +1,69 @@
+/*-
+ * Copyright (c) 2006 Hajimu UMEMOTO <ume@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <dlfcn.h>
+#include <stddef.h>
+
+#include "iconv.h"
+
+#undef iconv_open
+#undef iconv
+#undef iconv_close
+
+#define ICONVLIB	"libiconv.so"
+#define ICONV_ENGINE	"iconv"
+#define ICONV_OPEN	"iconv_open"
+#define ICONV_CLOSE	"iconv_close"
+
+typedef iconv_t iconv_open_t(const char *, const char *);
+
+dl_iconv_t *dl_iconv;
+dl_iconv_close_t *dl_iconv_close;
+
+static int initialized;
+static void *iconvlib;
+static iconv_open_t *iconv_open;
+
+iconv_t
+dl_iconv_open(const char *tocode, const char *fromcode)
+{
+	if (initialized) {
+		if (iconvlib == NULL)
+			return (iconv_t)-1;
+	} else {
+		initialized = 1;
+		iconvlib = dlopen(ICONVLIB, RTLD_LAZY | RTLD_GLOBAL);
+		if (iconvlib == NULL)
+			return (iconv_t)-1;
+		iconv_open = (iconv_open_t *)dlfunc(iconvlib, ICONV_OPEN);
+		dl_iconv = (dl_iconv_t *)dlfunc(iconvlib, ICONV_ENGINE);
+		dl_iconv_close = (dl_iconv_close_t *)dlfunc(iconvlib,
+		    ICONV_CLOSE);
+	}
+	return iconv_open(tocode, fromcode);
+}