Autoconf: Print the GNU C Library version when needed in autogen.sh

[tcpdump] / autogen.sh

diff --git a/autogen.sh b/autogen.sh
index c84a6b5c5dd256080187e14cd2a1d48dc49296b9..2ff00d3ee546dd2fadeaaee2185917b85eea17a2 100755 (executable)
--- a/autogen.sh
+++ b/autogen.sh
@@ -1,6 +1,7 @@
 #!/bin/sh -e
 
 : "${AUTORECONF:=autoreconf}"
+: "${BUILD_YEAR2038:=no}"
 
 AUTORECONFVERSION=`$AUTORECONF --version 2>&1 | grep "^autoreconf" | sed 's/.*) *//'`
 
@@ -21,5 +22,27 @@ if [ "$maj" = "" ] || [ "$min" = "" ] || \
        exit 1
 fi
 
+# On Linux, if Autoconf version >= 2.72 and GNU C Library version >= 2.34,
+# s/AC_SYS_LARGEFILE/AC_SYS_YEAR2038_RECOMMENDED/ to ensure time_t
+# is Y2038-safe.
+if [ "$BUILD_YEAR2038" = yes ] && [ "`uname -s`" = Linux ]; then
+       if [ "$maj" -gt 2 ] || { [ "$maj" -eq 2 ] && [ "$min" -ge 72 ]; }; then
+               GLIBC_VERSION=`ldd --version|head -1|grep GLIBC|sed 's/.* //'`
+               maj_glibc=`echo "$GLIBC_VERSION" | cut -d. -f1`
+               min_glibc=`echo "$GLIBC_VERSION" | cut -d. -f2`
+               echo "GNU C Library identification: $GLIBC_VERSION"
+               if [ "$maj_glibc" -gt 2 ] || { [ "$maj_glibc" -eq 2 ] && \
+                  [ "$min_glibc" -ge 34 ]; }; then
+                       CONFIGURE_AC_NEW="configure.ac.new$$"
+                       sed 's/^# \(AC_SYS_YEAR2038_RECOMMENDED\)/\1/' \
+                               <configure.ac >"$CONFIGURE_AC_NEW"
+                       cmp -s configure.ac "$CONFIGURE_AC_NEW" || \
+                       cat "$CONFIGURE_AC_NEW" >configure.ac
+                       rm -f "$CONFIGURE_AC_NEW"
+                       echo 'Setup to ensure time_t is Y2038-safe.'
+               fi
+       fi
+fi
+
 echo "$AUTORECONF identification: $AUTORECONFVERSION"
 "$AUTORECONF" -f