m4/libunistring.m4

   1 # libunistring.m4 serial 12
   2 dnl Copyright (C) 2009-2021 Free Software Foundation, Inc.
   3 dnl This file is free software; the Free Software Foundation
   4 dnl gives unlimited permission to copy and/or distribute it,
   5 dnl with or without modifications, as long as this notice is preserved.
   6
   7 AC_PREREQ([2.64])
   8
   9 dnl gl_LIBUNISTRING
  10 dnl Searches for an installed libunistring.
  11 dnl If found, it sets and AC_SUBSTs HAVE_LIBUNISTRING=yes and the LIBUNISTRING
  12 dnl and LTLIBUNISTRING variables, sets the LIBUNISTRING_VERSION variable, and
  13 dnl augments the CPPFLAGS variable, and #defines HAVE_LIBUNISTRING to 1.
  14 dnl Otherwise, it sets and AC_SUBSTs HAVE_LIBUNISTRING=no and LIBUNISTRING and
  15 dnl LTLIBUNISTRING to empty.
  16
  17 dnl Define gl_LIBUNISTRING using AC_DEFUN_ONCE, in order dnl to avoid warnings
  18 dnl like
  19 dnl "warning: AC_REQUIRE: `gl_LIBUNISTRING' was expanded before it was required".
  20 dnl This is tricky because of the way 'aclocal' is implemented:
  21 dnl - It requires defining an auxiliary macro whose name ends in AC_DEFUN.
  22 dnl   Otherwise aclocal's initial scan pass would miss the macro definition.
  23 dnl - It requires a line break inside the AC_DEFUN_ONCE and AC_DEFUN expansions.
  24 dnl   Otherwise aclocal would emit many "Use of uninitialized value $1"
  25 dnl   warnings.
  26 AC_DEFUN_ONCE([gl_LIBUNISTRING],
  27 [
  28   AC_BEFORE([$0], [gl_LIBUNISTRING_MODULE])
  29   AC_BEFORE([$0], [gl_LIBUNISTRING_LIBHEADER])
  30   AC_BEFORE([$0], [gl_LIBUNISTRING_LIB_PREPARE])
  31
  32   m4_ifdef([gl_LIBUNISTRING_OPTIONAL],
  33     [
  34       AC_MSG_CHECKING([whether included libunistring is requested])
  35       AC_ARG_WITH([included-libunistring],
  36         [  --with-included-libunistring  use the libunistring parts included here],
  37         [gl_libunistring_force_included=$withval],
  38         [gl_libunistring_force_included=no])
  39       AC_MSG_RESULT([$gl_libunistring_force_included])
  40       gl_libunistring_use_included="$gl_libunistring_force_included"
  41       if test "$gl_libunistring_use_included" = yes; then
  42         dnl Assume that libunistring is not installed until some other macro
  43         dnl explicitly invokes gl_LIBUNISTRING_CORE.
  44         if test -z "$HAVE_LIBUNISTRING"; then
  45           HAVE_LIBUNISTRING=no
  46         fi
  47         LIBUNISTRING=
  48         LTLIBUNISTRING=
  49       else
  50         gl_LIBUNISTRING_CORE
  51         if test $HAVE_LIBUNISTRING = no; then
  52           gl_libunistring_use_included=yes
  53           LIBUNISTRING=
  54           LTLIBUNISTRING=
  55         fi
  56       fi
  57     ],
  58     [gl_LIBUNISTRING_CORE])
  59 ])
  60
  61 AC_DEFUN([gl_LIBUNISTRING_CORE],
  62 [
  63   AC_REQUIRE([AM_ICONV])
  64   if test -n "$LIBICONV"; then
  65     dnl First, try to link without -liconv. libunistring often depends on
  66     dnl libiconv, but we don't know (and often don't need to know) where
  67     dnl libiconv is installed.
  68     AC_LIB_HAVE_LINKFLAGS([unistring], [],
  69       [#include <uniconv.h>], [u8_strconv_from_locale((char*)0);],
  70       [no, trying again together with libiconv])
  71     if test "$ac_cv_libunistring" != yes; then
  72       dnl Second try, with -liconv.
  73       dnl We have to erase the cached result of the first AC_LIB_HAVE_LINKFLAGS
  74       dnl invocation, otherwise the second one will not be run.
  75       unset ac_cv_libunistring
  76       glus_save_LIBS="$LIBS"
  77       LIBS="$LIBS $LIBICONV"
  78       AC_LIB_HAVE_LINKFLAGS([unistring], [],
  79         [#include <uniconv.h>], [u8_strconv_from_locale((char*)0);],
  80         [no, consider installing GNU libunistring])
  81       if test -n "$LIBUNISTRING"; then
  82         LIBUNISTRING="$LIBUNISTRING $LIBICONV"
  83         LTLIBUNISTRING="$LTLIBUNISTRING $LTLIBICONV"
  84       fi
  85       LIBS="$glus_save_LIBS"
  86     fi
  87   else
  88     AC_LIB_HAVE_LINKFLAGS([unistring], [],
  89       [#include <uniconv.h>], [u8_strconv_from_locale((char*)0);],
  90       [no, consider installing GNU libunistring])
  91   fi
  92   if test $HAVE_LIBUNISTRING = yes; then
  93     dnl Determine the installed version.
  94     AC_CACHE_CHECK([for libunistring version], [gl_cv_libunistring_version],
  95       [AC_COMPUTE_INT([gl_libunistring_hexversion],
  96                       [_LIBUNISTRING_VERSION],
  97                       [#include <unistring/version.h>])
  98        dnl Versions <= 0.9.3 had a hexversion of 0x0009.
  99        dnl Use other tests to distinguish them.
 100        if test $gl_libunistring_hexversion = 9; then
 101          dnl Version 0.9.2 introduced the header <unistring/cdefs.h>.
 102          AC_COMPILE_IFELSE(
 103            [AC_LANG_PROGRAM([[#include <unistring/cdefs.h>]], [[]])],
 104            [gl_cv_libunistring_version092=true],
 105            [gl_cv_libunistring_version092=false])
 106          if $gl_cv_libunistring_version092; then
 107            dnl Version 0.9.3 changed a comment in <unistr.h>.
 108            gl_ABSOLUTE_HEADER_ONE([unistr.h])
 109            if test -n "$gl_cv_absolute_unistr_h" \
 110               && grep 'Copy no more than N units of SRC to DEST.  Return a pointer' $gl_cv_absolute_unistr_h > /dev/null; then
 111              dnl Detected version 0.9.3.
 112              gl_libunistring_hexversion=2307
 113            else
 114              dnl Detected version 0.9.2.
 115              gl_libunistring_hexversion=2306
 116            fi
 117          else
 118            dnl Version 0.9.1 introduced the type casing_suffix_context_t.
 119            AC_COMPILE_IFELSE(
 120              [AC_LANG_PROGRAM(
 121                 [[#include <unicase.h>
 122                   casing_suffix_context_t ct;]],
 123                 [[]])],
 124              [gl_cv_libunistring_version091=true],
 125              [gl_cv_libunistring_version091=false])
 126            if $gl_cv_libunistring_version091; then
 127              dnl Detected version 0.9.1.
 128              gl_libunistring_hexversion=2305
 129            else
 130              dnl Detected version 0.9.
 131              gl_libunistring_hexversion=2304
 132            fi
 133          fi
 134        fi
 135        dnl Transform into the usual major.minor.subminor notation.
 136        gl_libunistring_major=`expr $gl_libunistring_hexversion / 65536`
 137        gl_libunistring_minor=`expr $gl_libunistring_hexversion / 256 % 256`
 138        gl_libunistring_subminor=`expr $gl_libunistring_hexversion % 256`
 139        gl_cv_libunistring_version="$gl_libunistring_major.$gl_libunistring_minor.$gl_libunistring_subminor"
 140       ])
 141     LIBUNISTRING_VERSION="$gl_cv_libunistring_version"
 142   fi
 143 ])