1 files changed, 70 insertions, 0 deletions
diff --git a/m4/iconv_h.m4 b/m4/iconv_h.m4
new file mode 100644
index 0000000..40c985e
--- /dev/null
+++ b/m4/iconv_h.m4
@@ -0,0 +1,70 @@
+# iconv_h.m4 serial 16
+dnl Copyright (C) 2007-2023 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN_ONCE([gl_ICONV_H],
+[
+  AC_REQUIRE([gl_ICONV_H_DEFAULTS])
+
+  dnl Execute this unconditionally, because GL_GENERATE_ICONV_H may be set to
+  dnl true by other modules, after this code is executed.
+  gl_CHECK_NEXT_HEADERS([iconv.h])
+
+  dnl Check for declarations of anything we want to poison if the
+  dnl corresponding gnulib module is not in use, and which is not
+  dnl guaranteed by C89.
+  gl_WARN_ON_USE_PREPARE([[#include <iconv.h>
+    ]], [iconv iconv_open])
+
+  AC_REQUIRE([AC_C_RESTRICT])
+])
+
+dnl Unconditionally enables the replacement of <iconv.h>.
+AC_DEFUN([gl_REPLACE_ICONV_H],
+[
+  gl_ICONV_H_REQUIRE_DEFAULTS
+  GL_GENERATE_ICONV_H=true
+])
+
+# gl_ICONV_MODULE_INDICATOR([modulename])
+# sets the shell variable that indicates the presence of the given module
+# to a C preprocessor expression that will evaluate to 1.
+# This macro invocation must not occur in macros that are AC_REQUIREd.
+AC_DEFUN([gl_ICONV_MODULE_INDICATOR],
+[
+  dnl Ensure to expand the default settings once only.
+  gl_ICONV_H_REQUIRE_DEFAULTS
+  gl_MODULE_INDICATOR_SET_VARIABLE([$1])
+])
+
+# Initializes the default values for AC_SUBSTed shell variables.
+# This macro must not be AC_REQUIREd.  It must only be invoked, and only
+# outside of macros or in macros that are not AC_REQUIREd.
+AC_DEFUN([gl_ICONV_H_REQUIRE_DEFAULTS],
+[
+  m4_defun(GL_MODULE_INDICATOR_PREFIX[_ICONV_H_MODULE_INDICATOR_DEFAULTS], [
+    gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_ICONV])
+  ])
+  m4_require(GL_MODULE_INDICATOR_PREFIX[_ICONV_H_MODULE_INDICATOR_DEFAULTS])
+  AC_REQUIRE([gl_ICONV_H_DEFAULTS])
+])
+
+AC_DEFUN([gl_ICONV_H_DEFAULTS],
+[
+  m4_ifdef([gl_ANSI_CXX], [AC_REQUIRE([gl_ANSI_CXX])])
+  dnl Assume proper GNU behavior unless another module says otherwise.
+  ICONV_CONST=;         AC_SUBST([ICONV_CONST])
+  REPLACE_ICONV=0;      AC_SUBST([REPLACE_ICONV])
+  REPLACE_ICONV_OPEN=0; AC_SUBST([REPLACE_ICONV_OPEN])
+  REPLACE_ICONV_UTF=0;  AC_SUBST([REPLACE_ICONV_UTF])
+  GL_GENERATE_ICONV_H=false
+  m4_ifdef([gl_POSIXCHECK],
+    [GL_GENERATE_ICONV_H=true],
+    [if m4_ifdef([gl_ANSI_CXX], [test "$CXX" != no], [false]); then
+       dnl Override <fnmatch.h> always, to support the C++ GNULIB_NAMESPACE.
+       GL_GENERATE_ICONV_H=true
+     fi
+    ])
+])