gnu: groff: Remove timestamps.

Fixes <https://bugs.gnu.org/27593>.

* gnu/packages/patches/groff-source-date-epoch.patch: New file.
* gnu/local.mk: Add it.
* gnu/packages/groff.scm (groff)[source]: Add it.

3 files changed, 302 insertions, 1 deletions

diff --git a/gnu/local.mk b/gnu/local.mk
index 23b8f449a1..0fe6cdc391 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -645,6 +645,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/graphite2-ffloat-store.patch		\
   %D%/packages/patches/grep-gnulib-lock.patch                   \
   %D%/packages/patches/grep-timing-sensitive-test.patch		\
+  %D%/packages/patches/groff-source-date-epoch.patch		\
   %D%/packages/patches/gsl-test-i686.patch			\
   %D%/packages/patches/gspell-dash-test.patch			\
   %D%/packages/patches/guile-1.8-cpp-4.5.patch			\
diff --git a/gnu/packages/groff.scm b/gnu/packages/groff.scm
index d7f45d4fc7..67dd1dbfa6 100644
--- a/gnu/packages/groff.scm
+++ b/gnu/packages/groff.scm
@@ -40,7 +40,8 @@
             (uri (string-append "mirror://gnu/groff/groff-" version
                                 ".tar.gz"))
             (sha256 (base32
-                     "1998v2kcs288d3y7kfxpvl369nqi06zbbvjzafyvyl3pr7bajj1s"))))
+                     "1998v2kcs288d3y7kfxpvl369nqi06zbbvjzafyvyl3pr7bajj1s"))
+            (patches (search-patches "groff-source-date-epoch.patch"))))
    (build-system gnu-build-system)
    (outputs '("out"
               "doc"))                    ;12MiB of PS, PDF, HTML, and examples
diff --git a/gnu/packages/patches/groff-source-date-epoch.patch b/gnu/packages/patches/groff-source-date-epoch.patch
new file mode 100644
index 0000000000..53c590b049
--- /dev/null
+++ b/gnu/packages/patches/groff-source-date-epoch.patch
@@ -0,0 +1,299 @@
+Adds support for the environment variable SOURCE_DATE_EPOCH.
+
+See: https://sources.debian.net/patches/groff/1.22.3-9/source-date-epoch.patch/
+
+From abc23bc9245e18468817f2838361c3a08f7521e2 Mon Sep 17 00:00:00 2001
+From: Colin Watson <cjwatson@debian.org>
+Date: Thu, 5 Nov 2015 11:47:34 +0000
+Subject: Implement `SOURCE_DATE_EPOCH' for reproducible builds.
+
+Author: Colin Watson <cjwatson@debian.org>
+Forwarded: yes
+Last-Update: 2015-11-05
+
+Patch-Name: source-date-epoch.patch
+---
+ doc/groff.texinfo                 |  6 +++++
+ src/devices/grohtml/grohtml.man   |  7 ++++++
+ src/devices/grohtml/post-html.cpp |  5 ++--
+ src/devices/gropdf/gropdf.man     |  7 ++++++
+ src/devices/gropdf/gropdf.pl      |  3 ++-
+ src/devices/grops/grops.man       |  7 ++++++
+ src/devices/grops/ps.cpp          |  3 ++-
+ src/include/curtime.h             | 23 ++++++++++++++++++
+ src/libs/libgroff/Makefile.sub    |  2 ++
+ src/libs/libgroff/curtime.cpp     | 51 +++++++++++++++++++++++++++++++++++++++
+ src/roff/troff/input.cpp          |  3 ++-
+ 11 files changed, 112 insertions(+), 5 deletions(-)
+ create mode 100644 src/include/curtime.h
+ create mode 100644 src/libs/libgroff/curtime.cpp
+
+diff --git a/doc/groff.texinfo b/doc/groff.texinfo
+index 066b5274..1d3c7a9f 100644
+--- a/doc/groff.texinfo
++++ b/doc/groff.texinfo
+@@ -1453,6 +1453,12 @@ default directory (on Unix and GNU/Linux systems, this is usually
+ @item GROFF_TYPESETTER
+ @tindex GROFF_TYPESETTER@r{, environment variable}
+ The default output device.
++
++@item SOURCE_DATE_EPOCH
++@tindex SOURCE_DATE_EPOCH@r{, environment variable}
++A timestamp (expressed as seconds since the Unix epoch) to use in place of
++the current time when initializing time-based built-in registers such as
++@code{\n[seconds]}.
+ @end table
+ 
+ Note that MS-DOS and MS-Windows ports of @code{groff} use semi-colons,
+diff --git a/src/devices/grohtml/grohtml.man b/src/devices/grohtml/grohtml.man
+index 51eae224..4be4abbc 100644
+--- a/src/devices/grohtml/grohtml.man
++++ b/src/devices/grohtml/grohtml.man
+@@ -419,6 +419,13 @@ and
+ for more details.
+ .
+ .
++.TP
++.SM
++.B SOURCE_DATE_EPOCH
++A timestamp (expressed as seconds since the Unix epoch) to use as the
++creation timestamp in place of the current time.
++.
++.
+ .\" --------------------------------------------------------------------
+ .SH BUGS
+ .\" --------------------------------------------------------------------
+diff --git a/src/devices/grohtml/post-html.cpp b/src/devices/grohtml/post-html.cpp
+index fefbf014..b5fc5167 100644
+--- a/src/devices/grohtml/post-html.cpp
++++ b/src/devices/grohtml/post-html.cpp
+@@ -28,6 +28,7 @@ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+ #include "html.h"
+ #include "html-text.h"
+ #include "html-table.h"
++#include "curtime.h"
+ 
+ #include <time.h>
+ 
+@@ -5013,7 +5014,7 @@ void html_printer::do_file_components (void)
+ 	.put_string(Version_string)
+ 	.end_comment();
+ 
+-      t = time(0);
++      t = current_time();
+       html.begin_comment("CreationDate: ")
+ 	.put_string(ctime(&t), strlen(ctime(&t))-1)
+ 	.end_comment();
+@@ -5126,7 +5127,7 @@ html_printer::~html_printer()
+     .put_string(Version_string)
+     .end_comment();
+ 
+-  t = time(0);
++  t = current_time();
+   html.begin_comment("CreationDate: ")
+     .put_string(ctime(&t), strlen(ctime(&t))-1)
+     .end_comment();
+diff --git a/src/devices/gropdf/gropdf.man b/src/devices/gropdf/gropdf.man
+index 3bbace6a..cc0c82f1 100644
+--- a/src/devices/gropdf/gropdf.man
++++ b/src/devices/gropdf/gropdf.man
+@@ -1029,6 +1029,13 @@ and
+ for more details.
+ .
+ .
++.TP
++.SM
++.B SOURCE_DATE_EPOCH
++A timestamp (expressed as seconds since the Unix epoch) to use as the
++creation timestamp in place of the current time.
++.
++.
+ .\" --------------------------------------------------------------------
+ .SH FILES
+ .\" --------------------------------------------------------------------
+diff --git a/src/devices/gropdf/gropdf.pl b/src/devices/gropdf/gropdf.pl
+index 035d1238..c25c4c67 100644
+--- a/src/devices/gropdf/gropdf.pl
++++ b/src/devices/gropdf/gropdf.pl
+@@ -239,13 +239,14 @@ elsif (exists($ppsz{$papersz}))
+     @defaultmb=@mediabox=(0,0,$ppsz{$papersz}->[0],$ppsz{$papersz}->[1]);
+ }
+ 
+-my (@dt)=localtime(time);
++my (@dt)=localtime($ENV{SOURCE_DATE_EPOCH} || time);
+ my $dt=PDFDate(\@dt);
+ 
+ my %info=('Creator' => "(groff version $cfg{GROFF_VERSION})",
+ 				'Producer' => "(gropdf version $cfg{GROFF_VERSION})",
+ 				'ModDate' => "($dt)",
+ 				'CreationDate' => "($dt)");
++
+ while (<>)
+ {
+     chomp;
+diff --git a/src/devices/grops/grops.man b/src/devices/grops/grops.man
+index 99fb7486..272c2d18 100644
+--- a/src/devices/grops/grops.man
++++ b/src/devices/grops/grops.man
+@@ -1419,6 +1419,13 @@ and
+ for more details.
+ .
+ .
++.TP
++.SM
++.B SOURCE_DATE_EPOCH
++A timestamp (expressed as seconds since the Unix epoch) to use as the
++creation timestamp in place of the current time.
++.
++.
+ .\" --------------------------------------------------------------------
+ .SH FILES
+ .\" --------------------------------------------------------------------
+diff --git a/src/devices/grops/ps.cpp b/src/devices/grops/ps.cpp
+index 745a503b..03e65372 100644
+--- a/src/devices/grops/ps.cpp
++++ b/src/devices/grops/ps.cpp
+@@ -28,6 +28,7 @@ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+ #include "cset.h"
+ #include "nonposix.h"
+ #include "paper.h"
++#include "curtime.h"
+ 
+ #include "ps.h"
+ #include <time.h>
+@@ -1390,7 +1391,7 @@ ps_printer::~ps_printer()
+ #else
+     time_t
+ #endif
+-    t = time(0);
++    t = current_time();
+     fputs(ctime(&t), out.get_file());
+   }
+   for (font_pointer_list *f = font_list; f; f = f->next) {
+diff --git a/src/include/curtime.h b/src/include/curtime.h
+new file mode 100644
+index 00000000..a4105196
+--- /dev/null
++++ b/src/include/curtime.h
+@@ -0,0 +1,23 @@
++/* Copyright (C) 2015  Free Software Foundation, Inc.
++
++This file is part of groff.
++
++groff is free software; you can redistribute it and/or modify it under
++the terms of the GNU General Public License as published by the Free
++Software Foundation, either version 2 of the License, or
++(at your option) any later version.
++
++groff is distributed in the hope that it will be useful, but WITHOUT ANY
++WARRANTY; without even the implied warranty of MERCHANTABILITY or
++FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
++for more details.
++
++The GNU General Public License version 2 (GPL2) is available in the
++internet at <http://www.gnu.org/licenses/gpl-2.0.txt>. */
++
++#ifdef LONG_FOR_TIME_T
++long
++#else
++time_t
++#endif
++current_time();
+diff --git a/src/libs/libgroff/Makefile.sub b/src/libs/libgroff/Makefile.sub
+index 840d9934..4cb4937a 100644
+--- a/src/libs/libgroff/Makefile.sub
++++ b/src/libs/libgroff/Makefile.sub
+@@ -32,6 +32,7 @@ OBJS=\
+   cmap.$(OBJEXT) \
+   color.$(OBJEXT) \
+   cset.$(OBJEXT) \
++  curtime.$(OBJEXT) \
+   device.$(OBJEXT) \
+   errarg.$(OBJEXT) \
+   error.$(OBJEXT) \
+@@ -82,6 +83,7 @@ CCSRCS=\
+   $(srcdir)/cmap.cpp \
+   $(srcdir)/color.cpp \
+   $(srcdir)/cset.cpp \
++  $(srcdir)/curtime.cpp \
+   $(srcdir)/device.cpp \
+   $(srcdir)/errarg.cpp \
+   $(srcdir)/error.cpp \
+diff --git a/src/libs/libgroff/curtime.cpp b/src/libs/libgroff/curtime.cpp
+new file mode 100644
+index 00000000..00821b7f
+--- /dev/null
++++ b/src/libs/libgroff/curtime.cpp
+@@ -0,0 +1,51 @@
++/* Copyright (C) 2015  Free Software Foundation, Inc.
++
++This file is part of groff.
++
++groff is free software; you can redistribute it and/or modify it under
++the terms of the GNU General Public License as published by the Free
++Software Foundation, either version 2 of the License, or
++(at your option) any later version.
++
++groff is distributed in the hope that it will be useful, but WITHOUT ANY
++WARRANTY; without even the implied warranty of MERCHANTABILITY or
++FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
++for more details.
++
++The GNU General Public License version 2 (GPL2) is available in the
++internet at <http://www.gnu.org/licenses/gpl-2.0.txt>. */
++
++#include <errno.h>
++#include <limits.h>
++#include <stdlib.h>
++#include <string.h>
++#include <time.h>
++
++#include "errarg.h"
++#include "error.h"
++
++#ifdef LONG_FOR_TIME_T
++long
++#else
++time_t
++#endif
++current_time()
++{
++  char *source_date_epoch = getenv("SOURCE_DATE_EPOCH");
++
++  if (source_date_epoch) {
++    errno = 0;
++    char *endptr;
++    long epoch = strtol(source_date_epoch, &endptr, 10);
++
++    if ((errno == ERANGE && (epoch == LONG_MAX || epoch == LONG_MIN)) ||
++	(errno != 0 && epoch == 0))
++      fatal("$SOURCE_DATE_EPOCH: strtol: %1", strerror(errno));
++    if (endptr == source_date_epoch)
++      fatal("$SOURCE_DATE_EPOCH: no digits found: %1", endptr);
++    if (*endptr != '\0')
++      fatal("$SOURCE_DATE_EPOCH: trailing garbage: %1", endptr);
++    return epoch;
++  } else
++    return time(0);
++}
+diff --git a/src/roff/troff/input.cpp b/src/roff/troff/input.cpp
+index 9594f074..f7d2c18a 100644
+--- a/src/roff/troff/input.cpp
++++ b/src/roff/troff/input.cpp
+@@ -36,6 +36,7 @@ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+ #include "input.h"
+ #include "defs.h"
+ #include "unicode.h"
++#include "curtime.h"
+ 
+ // Needed for getpid() and isatty()
+ #include "posix.h"
+@@ -8138,7 +8139,7 @@ static void init_registers()
+ #else /* not LONG_FOR_TIME_T */
+   time_t
+ #endif /* not LONG_FOR_TIME_T */
+-    t = time(0);
++    t = current_time();
+   // Use struct here to work around misfeature in old versions of g++.
+   struct tm *tt = localtime(&t);
+   set_number_reg("seconds", int(tt->tm_sec));