s3 aclocal.m4: Fix iconv checks, clean up m4 code

The check for iconv requiring giconv.h and libgiconv as well as
the check for iconv requiring biconv.h and libbiconv were using the wrong
variable to check for previous successful test results. This caused the checks
to always fall back to libbiconv on systems where that library was available.

In the course of fixing this, I had to clean up the indentation in that piece of
code, and I also rewrote/added some comments.

Many thanks to Tsurutani Naoki <turutani@scphys.kyoto-u.ac.jp> for the initial
patch and diagnosis.
(cherry picked from commit f5aff324cb9d965bbc75634596c3c40ffc588183)

Fix bug #4832 (iconv library is not used).
(cherry picked from commit a706038680ffcc3124b5e476810bffb1f7578c06)

diff --git a/source/m4/aclocal.m4 b/source/m4/aclocal.m4
index 9a4213d9767cb72e9d1e2e5b04d2282c8124dd03..52498a0a19e66e7471b42f685c6c257c3a9f884c 100644 (file)
--- a/source/m4/aclocal.m4
+++ b/source/m4/aclocal.m4
@@ -420,45 +420,47 @@ AC_DEFUN(jm_ICONV,
     jm_cv_giconv=no
     jm_save_LIBS="$LIBS"
 
-    dnl Check for include in funny place but no lib needed
-    if test "$jm_cv_func_iconv" != yes; then 
-      AC_TRY_LINK([#include <stdlib.h>
+  dnl Check for include in giconv.h but no lib needed
+  if test "$jm_cv_func_iconv" != yes; then
+    AC_TRY_LINK([#include <stdlib.h>
 #include <giconv.h>],
+      [iconv_t cd = iconv_open("","");
+       iconv(cd,NULL,NULL,NULL,NULL);
+       iconv_close(cd);],
+       jm_cv_func_iconv=yes
+       jm_cv_include="giconv.h"
+       jm_cv_giconv="yes"
+       jm_cv_lib_iconv="")
+
+    dnl Standard iconv.h include, lib in glibc or libc ...
+    if test "$jm_cv_func_iconv" != yes; then
+      AC_TRY_LINK([#include <stdlib.h>
+#include <iconv.h>],
         [iconv_t cd = iconv_open("","");
          iconv(cd,NULL,NULL,NULL,NULL);
          iconv_close(cd);],
+         jm_cv_include="iconv.h"
          jm_cv_func_iconv=yes
-         jm_cv_include="giconv.h"
-         jm_cv_giconv="yes"
          jm_cv_lib_iconv="")
 
-      dnl Standard iconv.h include, lib in glibc or libc ...
+      dnl Include in giconv.h, libgiconv needed to link
       if test "$jm_cv_func_iconv" != yes; then
+        jm_save_LIBS="$LIBS"
+        LIBS="$LIBS -lgiconv"
         AC_TRY_LINK([#include <stdlib.h>
-#include <iconv.h>],
+#include <giconv.h>],
           [iconv_t cd = iconv_open("","");
            iconv(cd,NULL,NULL,NULL,NULL);
            iconv_close(cd);],
-           jm_cv_include="iconv.h"
-           jm_cv_func_iconv=yes
-           jm_cv_lib_iconv="")
-
-          if test "$jm_cv_lib_iconv" != yes; then
-            jm_save_LIBS="$LIBS"
-            LIBS="$LIBS -lgiconv"
-            AC_TRY_LINK([#include <stdlib.h>
-#include <giconv.h>],
-              [iconv_t cd = iconv_open("","");
-               iconv(cd,NULL,NULL,NULL,NULL);
-               iconv_close(cd);],
-              jm_cv_lib_iconv=yes
-              jm_cv_func_iconv=yes
-              jm_cv_include="giconv.h"
-              jm_cv_giconv=yes
-              jm_cv_lib_iconv="giconv")
+          jm_cv_lib_iconv=yes
+          jm_cv_func_iconv=yes
+          jm_cv_include="giconv.h"
+          jm_cv_giconv=yes
+          jm_cv_lib_iconv="giconv")
 
-           LIBS="$jm_save_LIBS"
+        LIBS="$jm_save_LIBS"
 
+        dnl Include in iconv.h, libiconv needed to link
         if test "$jm_cv_func_iconv" != yes; then
           jm_save_LIBS="$LIBS"
           LIBS="$LIBS -liconv"
@@ -472,7 +474,8 @@ AC_DEFUN(jm_ICONV,
             jm_cv_lib_iconv="iconv")
           LIBS="$jm_save_LIBS"
 
-          if test "$jm_cv_lib_iconv" != yes; then
+          dnl Include in biconv.h, libbiconv needed to link
+          if test "$jm_cv_func_iconv" != yes; then
             jm_save_LIBS="$LIBS"
             LIBS="$LIBS -lbiconv"
             AC_TRY_LINK([#include <stdlib.h>
@@ -487,7 +490,7 @@ AC_DEFUN(jm_ICONV,
               jm_cv_lib_iconv="biconv")
 
             LIBS="$jm_save_LIBS"
-         fi
+          fi
         fi
       fi
     fi