Expose C library's gettext. Fixes #516412.

Doc/lib/liblocale.tex

@@ -467,3 +467,21 @@ application doesn't want this to happen, it should remove the
 \module{_locale} extension module (which does all the work) from the
 table of built-in modules in the \file{config.c} file, and make sure
 that the \module{_locale} module is not accessible as a shared library.
+
+\subsection{Access to message catalogs}
+
+The locale module exposes the C library's gettext interface on systems
+that provide this interface. It consists of the functions
+\function{gettext}, \function{dgettext}, \function{dcgettext},
+\function{textdomain}, and \function{bindtextdomain}. These are
+similar to the same functions in the \module{gettext} module, but use
+the C library's binary format for message catalogs, and the C
+library's search algorithms for locating message catalogs. 
+
+Python applications should normally find no need to invoke these
+functions, and should use \module{gettext} instead. A known exception
+to this rule are applications that link use additional C libraries
+which internally invoke \function{gettext} or \function{dgettext}. For
+these applications, it may be necessary to bind the text domain, so
+that the libraries can properly locate their message catalogs.
+

Misc/NEWS

@@ -31,6 +31,8 @@ Core and builtins
 
 Extension modules
 
+- The locale module now exposes the C library's gettext interface.
+
 - A security hole ("double free") was found in zlib-1.1.3, a popular
   third party compression library used by some Python modules.  The
   hole was quickly plugged in zlib-1.1.4, and the Windows build of

Modules/_localemodule.c

@@ -21,6 +21,10 @@ This software comes with no warranty. Use at your own risk.
 #include <langinfo.h>
 #endif
 
+#ifdef HAVE_LIBINTL_H
+#include <libintl.h>
+#endif
+
 #if defined(MS_WIN32)
 #define WINDOWS_LEAN_AND_MEAN
 #include <windows.h>
@@ -521,7 +525,86 @@ PyLocale_nl_langinfo(PyObject* self, PyObject* args)
     return NULL;
 }
 #endif /* HAVE_LANGINFO_H */
-    
+
+#ifdef HAVE_LIBINTL_H
+
+static char gettext__doc__[]=
+"gettext(msg) -> string\n"
+"Return translation of msg.";
+
+static PyObject*
+PyIntl_gettext(PyObject* self, PyObject *args)
+{
+	char *in;
+	if (!PyArg_ParseTuple(args, "z", &in))
+		return 0;
+	return PyString_FromString(gettext(in));
+}
+
+static char dgettext__doc__[]=
+"dgettext(domain, msg) -> string\n"
+"Return translation of msg in domain.";
+
+static PyObject*
+PyIntl_dgettext(PyObject* self, PyObject *args)
+{
+	char *domain, *in;
+	if (!PyArg_ParseTuple(args, "zz", &domain, &in))
+		return 0;
+	return PyString_FromString(dgettext(domain, in));
+}
+
+static char dcgettext__doc__[]=
+"dcgettext(domain, msg, category) -> string\n"
+"Return translation of msg in domain and category.";
+
+static PyObject*
+PyIntl_dcgettext(PyObject *self, PyObject *args)
+{
+	char *domain, *msgid;
+	int category;
+	if (!PyArg_ParseTuple(args, "zzi", &domain, &msgid, &category))
+		return 0;
+	return PyString_FromString(dcgettext(domain,msgid,category));
+}
+
+static char textdomain__doc__[]=
+"textdomain(domain) -> string\n"
+"Set the C library's textdmain to domain, returning the new domain.";
+
+static PyObject*
+PyIntl_textdomain(PyObject* self, PyObject* args)
+{
+	char *domain;
+	if (!PyArg_ParseTuple(args, "z", &domain))
+		return 0;
+	domain = textdomain(domain);
+	if (!domain) {
+		PyErr_SetFromErrno(PyExc_OSError);
+		return NULL;
+	}
+	return PyString_FromString(domain);
+}
+
+static char bindtextdomain__doc__[]=
+"bindtextdomain(domain, dir) -> string\n"
+"Bind the C library's domain to dir.";
+
+static PyObject*
+PyIntl_bindtextdomain(PyObject* self,PyObject*args)
+{
+	char *domain,*dirname;
+	if (!PyArg_ParseTuple(args, "zz", &domain, &dirname))
+		return 0;
+	dirname = bindtextdomain(domain, dirname);
+	if (!dirname) {
+		PyErr_SetFromErrno(PyExc_OSError);
+		return NULL;
+	}
+	return PyString_FromString(dirname);
+}
+
+#endif
 
 static struct PyMethodDef PyLocale_Methods[] = {
   {"setlocale", (PyCFunction) PyLocale_setlocale, 
@@ -539,7 +622,18 @@ static struct PyMethodDef PyLocale_Methods[] = {
   {"nl_langinfo", (PyCFunction) PyLocale_nl_langinfo,
    METH_VARARGS, nl_langinfo__doc__},
 #endif
-  
+#ifdef HAVE_LANGINFO_H
+  {"gettext",(PyCFunction)PyIntl_gettext,METH_VARARGS,
+    gettext__doc__},
+  {"dgettext",(PyCFunction)PyIntl_dgettext,METH_VARARGS,
+   dgettext__doc__},
+  {"dcgettext",(PyCFunction)PyIntl_dcgettext,METH_VARARGS,
+    dcgettext__doc__},
+  {"textdomain",(PyCFunction)PyIntl_textdomain,METH_VARARGS,
+   textdomain__doc__},
+  {"bindtextdomain",(PyCFunction)PyIntl_bindtextdomain,METH_VARARGS,
+   bindtextdomain__doc__},
+#endif  
   {NULL, NULL}
 };
 

configure.in

@@ -520,8 +520,8 @@ dnl AC_MSG_RESULT($cpp_type)
 
 # checks for header files
 AC_HEADER_STDC
-AC_CHECK_HEADERS(dlfcn.h fcntl.h grp.h limits.h langinfo.h locale.h \
-ncurses.h poll.h pthread.h \
+AC_CHECK_HEADERS(dlfcn.h fcntl.h grp.h limits.h langinfo.h \
+libintl.h locale.h ncurses.h poll.h pthread.h \
 signal.h stdarg.h stddef.h stdlib.h thread.h unistd.h utime.h termios.h \
 sys/audioio.h sys/file.h sys/lock.h sys/modem.h db_185.h db.h \
 sys/param.h sys/poll.h sys/select.h sys/socket.h sys/time.h sys/times.h \

pyconfig.h.in

@@ -645,6 +645,9 @@
 /* Define if you have the <langinfo.h> header file.  */
 #undef HAVE_LANGINFO_H
 
+/* Define if you have the <libintl.h> header file.  */
+#undef HAVE_LIBINTL_H
+
 /* Define if you have the <libutil.h> header file.  */
 #undef HAVE_LIBUTIL_H