From 51ad2b56dce42fa1a44ba663946ffe04bd3e4378 Mon Sep 17 00:00:00 2001

From: James McCoy <[email protected]>

Date: Thu, 28 Jan 2016 10:55:11 -0500

Subject: [PATCH] Support defining compilation date in $SOURCE_DATE_EPOCH

There is an ongoing effort[0] to make FOSS software reproducibly

buildable.  In order to make Vim build reproducibly, it is necessary to

allow defining the date/time that is part of VIM_VERSION_LONG as part of

the build process.

This commit enables that by adding support for the SOURCE_DATE_EPOCH

spec[1].  When the $SOURCE_DATE_EPOCH environment variable is defined,

it will be used to populate the BUILD_DATE preprocessor define.

If BUILD_DATE is not defined, the existing behavior of relying on the

preprocessor's __DATE__/__TIME__ symbols will be used.

[0]: https://reproducible-builds.org/

[1]: https://reproducible-builds.org/specs/source-date-epoch/

---

 src/config.h.in  |  3 +++

 src/configure.in | 10 ++++++++++

 src/version.c    |  6 ++++++

 3 files changed, 19 insertions(+)

diff --git a/src/auto/configure b/src/auto/configure

index fea1f2c..4698269 100755

--- a/src/auto/configure

+++ b/src/auto/configure

@@ -4081,6 +4081,15 @@ $as_echo "#define HAVE_SYS_WAIT_H 1" >>confdefs.h

 fi

+if test -n "$SOURCE_DATE_EPOCH"; then

+  DATE_FMT="%b %d %Y %H:%M:%S"

+  BUILD_DATE=$(LC_ALL=C gdate -u -d "@$SOURCE_DATE_EPOCH" "+$DATE_FMT" 2>/dev/null || LC_ALL=C date -u -r "$SOURCE_DATE_EPOCH" "+$DATE_FMT" 2>/dev/null || LC_ALL=C date -u "+$DATE_FMT")

+  cat >>confdefs.h <<_ACEOF

+#define BUILD_DATE "$BUILD_DATE"

+_ACEOF

+

+fi

+

 { $as_echo "$as_me:${as_lineno-$LINENO}: checking --enable-fail-if-missing argument" >&5

 $as_echo_n "checking --enable-fail-if-missing argument... " >&6; }

diff --git a/src/config.h.in b/src/config.h.in

index 8e115f5..2b64247 100644

--- a/src/config.h.in

+++ b/src/config.h.in

@@ -30,6 +30,9 @@

 /* Define when __DATE__ " " __TIME__ can be used */

 #undef HAVE_DATE_TIME

+/* Defined as the date of last modification */

+#undef BUILD_DATE

+

 /* Define when __attribute__((unused)) can be used */

 #undef HAVE_ATTRIBUTE_UNUSED

diff --git a/src/configure.in b/src/configure.in

index 92a1bb5..70367ca 100644

--- a/src/configure.in

+++ b/src/configure.in

@@ -29,6 +29,16 @@ dnl in autoconf needs it, where it uses STDC_HEADERS.

 AC_HEADER_STDC

 AC_HEADER_SYS_WAIT

+dnl If $SOURCE_DATE_EPOCH is present in the environment, use that as the

+dnl "compiled" timestamp in :version's output.  Attempt to get the formatted

+dnl date using GNU date syntax, BSD date syntax, and finally falling back to

+dnl just using the current time.

+if test -n "$SOURCE_DATE_EPOCH"; then

+  DATE_FMT="%b %d %Y %H:%M:%S"

+  BUILD_DATE=$(LC_ALL=C gdate -u -d "@$SOURCE_DATE_EPOCH" "+$DATE_FMT" 2>/dev/null || LC_ALL=C date -u -r "$SOURCE_DATE_EPOCH" "+$DATE_FMT" 2>/dev/null || LC_ALL=C date -u "+$DATE_FMT")

+  AC_DEFINE_UNQUOTED(BUILD_DATE, ["$BUILD_DATE"])

+fi

+

 dnl Check for the flag that fails if stuff are missing.

 AC_MSG_CHECKING(--enable-fail-if-missing argument)

diff --git a/src/version.c b/src/version.c

index 766937d..9cb6e57 100644

--- a/src/version.c

+++ b/src/version.c

@@ -44,11 +44,17 @@ make_version(void)

      * VAX C can't catenate strings in the preprocessor.

      */

     strcpy(longVersion, VIM_VERSION_LONG_DATE);

+#ifdef BUILD_DATE

+    strcat(longVersion, BUILD_DATE);

+#else

     strcat(longVersion, __DATE__);

     strcat(longVersion, " ");

     strcat(longVersion, __TIME__);

+#endif

     strcat(longVersion, ")");

 }

+# elif defined(BUILD_DATE)

+char	*longVersion = VIM_VERSION_LONG_DATE BUILD_DATE ")";

 # else

 char	*longVersion = VIM_VERSION_LONG_DATE __DATE__ " " __TIME__ ")";

 # endif