From: Ken Hornstein <kenh@pobox.com>
Date: Tue, 1 Jan 2013 07:40:30 +0000 (-0500)
Subject: Clean up (and hopefully improve) the autoconf iconv tests.
X-Git-Url: https://diplodocus.org/git/nmh/commitdiff_plain/b3df58528443af8b4f25748bef8ca98852af9ba2?ds=inline;hp=--cc

Clean up (and hopefully improve) the autoconf iconv tests.
---

b3df58528443af8b4f25748bef8ca98852af9ba2
diff --git a/configure.ac b/configure.ac
index f6fa38ec..7887b993 100644
--- a/configure.ac
+++ b/configure.ac
@@ -437,7 +437,7 @@ AS_CASE(["$host_os"],
 AC_HEADER_STDC
 AC_HEADER_TIOCGWINSZ
 AC_CHECK_HEADERS([errno.h fcntl.h crypt.h ncurses/termcap.h termcap.h \
-                  langinfo.h wchar.h wctype.h iconv.h netdb.h \
+                  langinfo.h wchar.h wctype.h netdb.h \
                   sys/param.h sys/time.h sys/stream.h])
 
 dnl
@@ -481,8 +481,12 @@ AC_CHECK_FUNC([modf], , AC_CHECK_LIB([m], [modf]))
 dnl Checks for network libraries (nsl, socket)
 NMH_CHECK_NETLIBS
 
+dnl Check for readline support
 NMH_READLINE
 
+dnl Check for iconv
+NMH_CHECK_ICONV
+
 termcap_curses_order="termcap curses ncurses"
 for lib in $termcap_curses_order; do
   AC_CHECK_LIB(${lib}, tgetent, [TERMLIB="-l$lib"; break])
@@ -492,53 +496,6 @@ AS_IF([test "x$TERMLIB" = "x"],
       [AC_MSG_FAILURE([Could not find tgetent in any library.  Is there a curses
 or ncurses library or package that you can install?])])
 
-
-dnl ---------------
-dnl CHECK FOR ICONV
-dnl ---------------
-
-dnl Find iconv. It may be in libiconv and may be iconv() or libiconv()
-if test "x$ac_cv_header_iconv_h" = "xyes"; then
-  AC_CHECK_FUNC(iconv, ac_found_iconv=yes, ac_found_iconv=no)
-  if test "x$ac_found_iconv" = "xno"; then
-    AC_CHECK_LIB(iconv, iconv, ac_found_iconv=yes)
-    if test "x$ac_found_iconv" = "xno"; then
-      AC_CHECK_LIB(iconv, libiconv, ac_found_iconv=yes)
-    fi
-    if test "x$ac_found_iconv" != "xno"; then
-      ICONVLIB="-liconv"
-    fi
-  else
-    dnl Handle case where there is a native iconv but iconv.h is from libiconv
-    AC_CHECK_DECL(_libiconv_version,
-      [ AC_CHECK_LIB(iconv, libiconv, LIBS="-liconv $LIBS") ],,
-      [ #include <iconv.h> ])
-  fi
-fi
-if test "x$ac_found_iconv" = xyes; then
-  AC_DEFINE([HAVE_ICONV], [1], [Define if you have the iconv() function.])
-fi
-AC_SUBST([ICONVLIB])
-
-dnl Check if iconv uses const in prototype declaration
-if test "x$ac_found_iconv" = "xyes"; then
-  AC_CACHE_CHECK(for iconv declaration, ac_cv_iconv_const,
-    [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <stdlib.h>
-        #include <iconv.h>]],
-        [[#ifdef __cplusplus
-          "C"
-          #endif
-          #if defined(__STDC__) || defined(__cplusplus)
-          size_t iconv (iconv_t cd, char * *inbuf, size_t *inbytesleft, char * *outbuf, size_t *outbytesleft);
-          #else
-          size_t iconv();
-          #endif]])],
-      [ac_cv_iconv_const=],
-      [ac_cv_iconv_const=const])])
-  AC_DEFINE_UNQUOTED([ICONV_CONST], $ac_cv_iconv_const,
-    [Define as const if the declaration of iconv() needs const.])
-fi
-
 dnl --------------
 dnl CHECK FOR NDBM
 dnl --------------
diff --git a/m4/iconv.m4 b/m4/iconv.m4
new file mode 100644
index 00000000..949c746d
--- /dev/null
+++ b/m4/iconv.m4
@@ -0,0 +1,42 @@
+dnl
+dnl Check for iconv support.  It may be in libiconv and may be iconv()
+dnl or libiconv()
+dnl
+
+AC_DEFUN([NMH_CHECK_ICONV],
+[AC_CHECK_HEADER([iconv.h],
+  [AC_CHECK_FUNC([iconv],
+    [dnl This is where iconv is found in the default libraries (LIBS)
+    nmh_found_iconv=yes
+    dnl Handle the case where there is a native iconv but iconv.h is
+    dnl from libiconv
+    AC_CHECK_DECL([_libiconv_version],
+      [AC_CHECK_LIB([iconv], [libiconv], [LIBS="-liconv $LIBS"])],,
+      [#include <iconv.h>])],
+    [dnl Since we didn't find iconv in LIBS, check libiconv
+    AC_CHECK_LIB([iconv], [iconv], [nmh_found_iconv=yes],
+      [dnl Also check for a function called libiconv()
+      AC_CHECK_LIB([iconv], [libiconv], [nmh_found_iconv=yes])])
+    dnl If either of these tests pass, set ICONVLIB
+    AS_IF([test "x$nmh_found_iconv" = "xyes"], [ICONVLIB="-liconv"])])
+  dnl If we came out of that by finding iconv in some form, define
+  dnl HAVE_ICONV
+  AS_IF([test "x$nmh_found_iconv" = "xyes"],
+    [AC_DEFINE([HAVE_ICONV], [1],
+		   [Define if you have the iconv() function.])
+    AC_CACHE_CHECK([for iconv declaration], [nmh_cv_iconv_const],
+      [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <stdlib.h>
+          #include <iconv.h>]],
+	  [[#ifdef __cplusplus
+	    "C"
+	    #endif
+	    #if defined(__STDC__) || defined(__cplusplus)
+	    size_t iconv (iconv_t cd, char * *inbuf, size_t *inbytesleft, char * *outbuf, size_t *outbytesleft);
+	    #else
+	    size_t iconv();
+	    #endif]])],
+        [nmh_cv_iconv_const=],
+	[nmh_cv_iconv_const=const])])
+    AC_DEFINE_UNQUOTED([ICONV_CONST], [$nmh_cv_iconv_const],
+      [Define as const if the declaration of iconv() needs const.])])])
+AC_SUBST([ICONVLIB])])