use pkg-config to get the zlib cflags/libs; remove obsolete zlib.m4 macro

cli/Makefile.am

@@ -7,9 +7,6 @@ AM_CFLAGS = \
     @ZLIB_CFLAGS@ \
     @PTHREAD_CFLAGS@
 
-AM_LDFLAGS = \
-    @ZLIB_LDFLAGS@
-
 bin_PROGRAMS = transmission-cli
 
 dist_man_MANS = transmission-cli.1

configure.ac

@@ -42,6 +42,8 @@ LIBEVENT_MINIMUM=2.0.10
 AC_SUBST(LIBEVENT_MINIMUM)
 OPENSSL_MINIMUM=0.9.4
 AC_SUBST(OPENSSL_MINIMUM)
+ZLIB_MINIMUM=1.2.5
+AC_SUBST(ZLIB_MINIMUM)
 
 ##
 ##
@@ -112,7 +114,7 @@ AC_SEARCH_LIBS([quotacursor_skipidtype], [quota])
 PKG_CHECK_MODULES(OPENSSL, [openssl >= $OPENSSL_MINIMUM], , [CHECK_SSL()])
 PKG_CHECK_MODULES(LIBCURL, [libcurl >= $CURL_MINIMUM])
 PKG_CHECK_MODULES(LIBEVENT, [libevent >= $LIBEVENT_MINIMUM])
-AC_PATH_ZLIB
+PKG_CHECK_MODULES(ZLIB, [zlib >= $ZLIB_MINIMUM])
 
 AC_SYS_LARGEFILE
 AC_CHECK_FUNCS([lseek64])

daemon/Makefile.am

@@ -8,9 +8,6 @@ AM_CFLAGS = \
     @ZLIB_CFLAGS@ \
     @PTHREAD_CFLAGS@
 
-AM_LDFLAGS = \
-    @ZLIB_LDFLAGS@
-
 EXTRA_DIST = \
     transmission-daemon.service
 

gtk/Makefile.am

@@ -25,9 +25,6 @@ AM_CFLAGS = \
     @ZLIB_CFLAGS@ \
     @PTHREAD_CFLAGS@
 
-AM_LDFLAGS = \
-    @ZLIB_LDFLAGS@
-
 noinst_HEADERS = \
     actions.h \
     conf.h \

libtransmission/Makefile.am

@@ -161,9 +161,6 @@ TESTS = \
 
 noinst_PROGRAMS = $(TESTS)
 
-apps_ldflags = \
-  @ZLIB_LDFLAGS@
-
 apps_ldadd = \
   ./libtransmission.a  \
   @LIBUPNP_LIBS@ \

m4/zlib.m4

@@ -1,80 +0,0 @@
- AC_DEFUN([AC_PATH_ZLIB], [
-	AC_ARG_WITH(zlib,
-                    AC_HELP_STRING([--with-zlib=DIR],
-                                 [search for ZLIB in DIR/include and DIR/lib]),
-                    [for dir in `echo "$withval" | tr : ' '`; do
-    if test -d $dir/include; then
-      ZLIB_CFLAGS="$ZLIB_CFLAGS -I$dir/include"
-    fi
-    if test -d $dir/lib; then
-      ZLIB_LDFLAGS="$ZLIB_LDFLAGS -L$dir/lib"
-    fi
-  done[]])
-
-        AC_ARG_WITH(zlib-includes,
-                    AC_HELP_STRING([--with-zlib-includes=DIR],
-	                           [search for ZLIB includes in DIR]),
-	            [for dir in `echo "$withval" | tr : ' '`; do
-    if test -d $dir; then
-      ZLIB_CFLAGS="$ZLIB_CFLAGS -I$dir"
-    fi
-  done[]])
-
-ac_zlib_saved_CFLAGS="$CFLAGS"
-ac_zlib_saved_LDFLAGS="$LDFLAGS"
-ac_zlib_saved_LIBS="$LIBS"
-CFLAGS="$CFLAGS $ZLIB_CFLAGS"
-LDFLAGS="$LDFLAGS $ZLIB_LDFLAGS"
-ac_have_zlibh=no
-ac_have_zlib=no
-  	touch /tmp/dummy1_zlib.h
-        AC_CHECK_HEADERS([/tmp/dummy1_zlib.h], [ac_have_zlibh=yes], [ac_have_zlibh=no],
-		[#include "zlib.h"])
-	rm /tmp/dummy1_zlib.h
- 	if test $ac_have_zlibh = yes; then
-        	AC_SEARCH_LIBS(gzopen, [z], [ac_have_zlib=yes], [ac_have_zlib=no])
-	fi
-# List of places to try
-testdirs="$HOME/opt/zlib $OBITINSTALL/other"
-for dir in $testdirs; do
-	if test $ac_have_zlib = no; then
-		if  test -f $dir/include/zlib.h; then
-			ZLIB_CFLAGS="-I$dir/include"
-			CPPFLAGS="$ac_zlib_saved_CPPFLAGS $ZLIB_CFLAGS"
-			ZLIB_LDFLAGS="-L$dir/lib"
-			LDFLAGS="$ac_zlib_saved_LDFLAGS $ZLIB_LDFLAGS"
-  			touch /tmp/dummy3_zlib.h
- 		        AC_CHECK_HEADERS([/tmp/dummy3_zlib.h], [ac_have_zlibh=yes], [ac_have_zlibh=no],
-				[#include "zlib.h"])
-			rm /tmp/dummy3_zlib.h
-			if test $ac_have_zlibh = yes; then
-				# Force check
-				ac_cv_search_gzopen="  "
-		        	AC_SEARCH_LIBS(gzopen, [z], [ac_have_zlib=yes], [ac_have_zlib=no])
-			fi
-			if test $ac_have_zlib = yes ; then
-				if test $ac_have_zlibh = yes ; then
-					break;
-				fi
-			fi
-		fi
-	fi
-done[]
-if test $ac_have_zlib = no; then
-	AC_MSG_WARN([cannot find ZLIB library])
-fi
-if test $ac_have_zlibh = no; then
-	AC_MSG_WARN([cannot find ZLIB headers])
-	ac_have_zlib=no
-fi
-if test $ac_have_zlib = yes; then
-	AC_DEFINE(HAVE_ZLIB, 1, [Define to 1 if ZLIB is available.])
-fi
-ZLIB_LIBS="$LIBS"
-CFLAGS="$ac_zlib_saved_CFLAGS"
-LDFLAGS="$ac_zlib_saved_LDFLAGS"
-LIBS="$ac_zlib_saved_LIBS"
-	AC_SUBST(ZLIB_CFLAGS)
-	AC_SUBST(ZLIB_LDFLAGS)
-	AC_SUBST(ZLIB_LIBS)
-])

utils/Makefile.am

@@ -7,9 +7,6 @@ AM_CFLAGS = \
     @ZLIB_CFLAGS@ \
     @PTHREAD_CFLAGS@
 
-AM_LDFLAGS = \
-    @ZLIB_LDFLAGS@
-
 bin_PROGRAMS = \
     transmission-create \
     transmission-edit \