Improve reproducibility if SOURCE_DATE_EPOCH if set (GH pull/89).

configure.ac: Define SOURCE_DATE_EPOCH in CPPFLAGS.
utility.cpp: Print SOURCE_DATE_EPOCH value if specified.
Don't include configure arguments then.
cppcheck.sh: Silence related 'ConfigurationNotChecked' message.

git-svn-id: http://svn.code.sf.net/p/smartmontools/code/trunk@5201 4ea69e1a-61f1-4043-bf83-b5c94c648137

smartmontools/ChangeLog

@@ -2,6 +2,12 @@ $Id$
 
 2021-02-07  Christian Franke  <franke@computer.org>
 
+	Improve reproducibility if SOURCE_DATE_EPOCH if set (GH pull/89).
+	configure.ac: Define SOURCE_DATE_EPOCH in CPPFLAGS.
+	utility.cpp: Print SOURCE_DATE_EPOCH value if specified.
+	Don't include configure arguments then.
+	cppcheck.sh: Silence related 'ConfigurationNotChecked' message.
+
 	Always add timestamp to JSON output (#1436).
 	Move non-JSON timestamp output to common function.
 

smartmontools/configure.ac

@@ -61,6 +61,18 @@ case "${host}" in
     ;;
 esac
 
+AC_MSG_CHECKING([whether reproducible build is selected (SOURCE_DATE_EPOCH)])
+res=no
+if test -n "$SOURCE_DATE_EPOCH"; then
+  res=yes
+  test -z "`echo "$SOURCE_DATE_EPOCH" | sed 's,[[0-9]]*,,'`" || res=error
+fi
+AC_MSG_RESULT([$res])
+case $res in
+  error) AC_MSG_ERROR([Malformed SOURCE_DATE_EPOCH]) ;;
+  yes) CPPFLAGS="${CPPFLAGS}${CPPFLAGS:+ }-DSOURCE_DATE_EPOCH=$SOURCE_DATE_EPOCH" ;;
+esac
+
 # Check for SVN.
 AC_MSG_CHECKING([whether this is a build from SVN])
 is_svn_build=no

smartmontools/cppcheck.sh

@@ -109,6 +109,7 @@ defs="\
   -DSMARTMONTOOLS_ATTRIBUTELOG=\"/file\"
   -DSMARTMONTOOLS_SAVESTATES=\"/file\"
   -DSMARTMONTOOLS_DRIVEDBDIR=\"/dir\"
+  -DSOURCE_DATE_EPOCH=1665402854
   -Umakedev
   -Ustricmp"
 

smartmontools/utility.cpp

@@ -134,9 +134,19 @@ std::string format_version_info(const char * prog_name, bool full /*= false*/)
 #endif
                                                           "\n"
     "smartmontools configure arguments:"
+#ifdef SOURCE_DATE_EPOCH
+                                      " [hidden in reproducible builds]\n"
+    "reproducible build SOURCE_DATE_EPOCH: "
+#endif
   ;
+#ifdef SOURCE_DATE_EPOCH
+  char ts[32]; struct tm tmbuf;
+  strftime(ts, sizeof(ts), "%Y-%m-%d %H:%M:%S", time_to_tm_local(&tmbuf, SOURCE_DATE_EPOCH));
+  info += strprintf("%u (%s)", (unsigned)SOURCE_DATE_EPOCH, ts);
+#else
   info += (sizeof(SMARTMONTOOLS_CONFIGURE_ARGS) > 1 ?
            SMARTMONTOOLS_CONFIGURE_ARGS : " [no arguments given]");
+#endif
   info += '\n';
 
   return info;