tools/zip/patches/011-reproducible-mtime.patch

   1 From 501ae4e93fd6fa2f7d20d00d1b011f9006802eae Mon Sep 17 00:00:00 2001
   2 From: "Bernhard M. Wiedemann" <bwiedemann@suse.de>
   3 Date: Fri, 3 May 2019 16:32:24 +0200
   4 Subject: [PATCH] Override mtime with zip -X
   5
   6 with SOURCE_DATE_EPOCH
   7 to allow for reproducible builds of .zip files
   8
   9 See https://reproducible-builds.org/ for why this is good
  10 and https://reproducible-builds.org/specs/source-date-epoch/
  11 for the definition of this variable.
  12
  13 Uses clamping to keep older mtimes than SOURCE_DATE_EPOCH intact.
  14 ---
  15  zipup.c | 8 ++++++++
  16  1 file changed, 8 insertions(+)
  17
  18 --- a/zipup.c
  19 +++ b/zipup.c
  20 @@ -414,6 +414,7 @@ struct zlist far *z;    /* zip entry to
  21    ush tempcext = 0;
  22    char *tempextra = NULL;
  23    char *tempcextra = NULL;
  24 +  const char *source_date_epoch;
  25
  26
  27  #ifdef WINDLL
  28 @@ -674,6 +675,13 @@ struct zlist far *z;    /* zip entry to
  29
  30    } /* strcmp(z->name, "-") == 0 */
  31
  32 +  if (extra_fields == 0 && (source_date_epoch = getenv("SOURCE_DATE_EPOCH")) != NULL) {
  33 +     time_t epoch = strtoull(source_date_epoch, NULL, 10);
  34 +     if (epoch > 0) {
  35 +       ulg epochtim = unix2dostime(&epoch);
  36 +       if (z->tim > epochtim) z->tim = epochtim;
  37 +     }
  38 +  }
  39    if (extra_fields == 2) {
  40      unsigned len;
  41      char *p;