Switch to using freetype-config for freetype detection.

This fixes GD compilation against libfreetype 2.5.1 and later after they made
the rather interesting decision to change their include directory layout in a
point release.

The original suggestion in the bug was to use pkg-config, but my inclination is
to use freetype-config instead: we should be able to get the same configuration
information without actually needing pkg-config installed, since pkg-config is
by no means guaranteed to exist on many Unices and distros, whereas
freetype-config should always be present if a libfreetype build environment is
installed. Let's try it out and see what happens.

Fixes bug #64405 (Use freetype-config for determining freetype2 dir(s)).

NEWS

@@ -20,6 +20,10 @@ PHP                                                                        NEWS
 - Filter:
   . Fixed bug #66229 (128.0.0.0/16 isn't reserved any longer). (Adam)
 
+- GD:
+  . Fixed bug #64405 (Use freetype-config for determining freetype2 dir(s)).
+    (Adam)
+
 - XSL
   . Fixed bug #49634 (Segfault throwing an exception in a XSL registered
     function). (Mike)

ext/gd/config.m4

@@ -193,30 +193,25 @@ AC_DEFUN([PHP_GD_FREETYPE2],[
   if test "$PHP_FREETYPE_DIR" != "no"; then
 
     for i in $PHP_FREETYPE_DIR /usr/local /usr; do
-      if test -f "$i/include/freetype2/freetype/freetype.h"; then
+      if test -f "$i/bin/freetype-config"; then
         FREETYPE2_DIR=$i
-        FREETYPE2_INC_DIR=$i/include/freetype2
+        FREETYPE2_CONFIG="$i/bin/freetype-config"
         break
       fi
     done
 
     if test -z "$FREETYPE2_DIR"; then
-      AC_MSG_ERROR([freetype.h not found.])
+      AC_MSG_ERROR([freetype-config not found.])
     fi
 
-    PHP_CHECK_LIBRARY(freetype, FT_New_Face,
-    [
-      PHP_ADD_LIBRARY_WITH_PATH(freetype, $FREETYPE2_DIR/$PHP_LIBDIR, GD_SHARED_LIBADD)
-      PHP_ADD_INCLUDE($FREETYPE2_DIR/include)
-      PHP_ADD_INCLUDE($FREETYPE2_INC_DIR)
-      AC_DEFINE(USE_GD_IMGSTRTTF, 1, [ ])
-      AC_DEFINE(HAVE_LIBFREETYPE,1,[ ])
-      AC_DEFINE(ENABLE_GD_TTF,1,[ ])
-    ],[
-      AC_MSG_ERROR([Problem with freetype.(a|so). Please check config.log for more information.])
-    ],[
-      -L$FREETYPE2_DIR/$PHP_LIBDIR
-    ])
+    FREETYPE2_CFLAGS=`$FREETYPE2_CONFIG --cflags`
+    FREETYPE2_LIBS=`$FREETYPE2_CONFIG --libs`
+
+    PHP_EVAL_INCLINE($FREETYPE2_CFLAGS)
+    PHP_EVAL_LIBLINE($FREETYPE2_LIBS, GD_SHARED_LIBADD)
+    AC_DEFINE(USE_GD_IMGSTRTTF, 1, [ ])
+    AC_DEFINE(HAVE_LIBFREETYPE,1,[ ])
+    AC_DEFINE(ENABLE_GD_TTF,1,[ ])
   else
     AC_MSG_RESULT([If configure fails try --with-freetype-dir=<DIR>])
   fi