[groff] 01/01: Implement `SOURCE_DATE_EPOCH' for reproducible builds.

[Colin Watson]

cjwatson pushed a commit to branch master
in repository groff.

commit e4290210f2c1db5292d97678197a986d6822d044
Author: Colin Watson <address@hidden>
Date:   Fri Jul 29 03:25:26 2016 +0100

    Implement `SOURCE_DATE_EPOCH' for reproducible builds.
    
    * src/include/curtime.h: New file.
    * src/libs/libgroff/curtime.cpp: New file.
    * src/libs/libgroff/libgroff.am (libgroff_a_SOURCES): Add
    src/libs/libgroff/curtime.cpp.
    
    * src/roff/troff/input.cpp (init_registers): Use `current_time'
    instead of `time(0)'.
    * src/devices/grohtml/post-html.cpp
    (html_printer::do_file_components): Likewise.
    (html_printer::~html_printer): Likewise.
    * src/devices/grops/ps.cpp (ps_printer::~ps_printer): Likewise.
    * src/devices/gropdf/gropdf.pl: Use `$ENV{SOURCE_DATE_EPOCH}` if
    available in preference to `time`.
    
    * doc/groff.texi (Environment): Document `SOURCE_DATE_EPOCH'.
    * src/devices/grohtml/grohtml.1.man (ENVIRONMENT): Likewise.
    * src/devices/gropdf/gropdf.1.man (ENVIRONMENT): Likewise.
    * src/devices/grops/grops.1.man (ENVIRONMENT): Likewise.
---
 ChangeLog                         |   23 +++++++++++++++++
 doc/groff.texi                    |    6 +++++
 src/devices/grohtml/grohtml.1.man |    7 +++++
 src/devices/grohtml/post-html.cpp |    5 ++--
 src/devices/gropdf/gropdf.1.man   |    7 +++++
 src/devices/gropdf/gropdf.pl      |    3 ++-
 src/devices/grops/grops.1.man     |    7 +++++
 src/devices/grops/ps.cpp          |    3 ++-
 src/include/curtime.h             |   23 +++++++++++++++++
 src/libs/libgroff/curtime.cpp     |   51 +++++++++++++++++++++++++++++++++++++
 src/libs/libgroff/libgroff.am     |    1 +
 src/roff/troff/input.cpp          |    3 ++-
 12 files changed, 134 insertions(+), 5 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 66961cc..156d23a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,26 @@
+2016-07-29  Colin Watson  <address@hidden>
+
+       Implement `SOURCE_DATE_EPOCH' for reproducible builds.
+
+       * src/include/curtime.h: New file.
+       * src/libs/libgroff/curtime.cpp: New file.
+       * src/libs/libgroff/libgroff.am (libgroff_a_SOURCES): Add
+       src/libs/libgroff/curtime.cpp.
+
+       * src/roff/troff/input.cpp (init_registers): Use `current_time'
+       instead of `time(0)'.
+       * src/devices/grohtml/post-html.cpp
+       (html_printer::do_file_components): Likewise.
+       (html_printer::~html_printer): Likewise.
+       * src/devices/grops/ps.cpp (ps_printer::~ps_printer): Likewise.
+       * src/devices/gropdf/gropdf.pl: Use `$ENV{SOURCE_DATE_EPOCH}` if
+       available in preference to `time`.
+
+       * doc/groff.texi (Environment): Document `SOURCE_DATE_EPOCH'.
+       * src/devices/grohtml/grohtml.1.man (ENVIRONMENT): Likewise.
+       * src/devices/gropdf/gropdf.1.man (ENVIRONMENT): Likewise.
+       * src/devices/grops/grops.1.man (ENVIRONMENT): Likewise.
+
 2016-04-19  Carsten Kunze  <address@hidden>
 
        eqn: Fix problem with explicite spacing before unary operator
diff --git a/doc/groff.texi b/doc/groff.texi
index 8db136e..7610fef 100644
--- a/doc/groff.texi
+++ b/doc/groff.texi
@@ -1453,6 +1453,12 @@ default directory (on Unix and GNU/Linux systems, this 
is usually
 @item GROFF_TYPESETTER
 @tindex address@hidden, environment variable}
 The default output device.
+
address@hidden SOURCE_DATE_EPOCH
address@hidden address@hidden, 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
address@hidden
 @end table
 
 Note that MS-DOS and MS-Windows ports of @code{groff} use semi-colons,
diff --git a/src/devices/grohtml/grohtml.1.man 
b/src/devices/grohtml/grohtml.1.man
index 2efdd81..f8c45dd 100644
--- a/src/devices/grohtml/grohtml.1.man
+++ b/src/devices/grohtml/grohtml.1.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 fefbf01..b5fc516 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.1.man b/src/devices/gropdf/gropdf.1.man
index 25287a6..4a06c0f 100644
--- a/src/devices/gropdf/gropdf.1.man
+++ b/src/devices/gropdf/gropdf.1.man
@@ -1024,6 +1024,13 @@ 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 0744378..b95169e 100644
--- a/src/devices/gropdf/gropdf.pl
+++ b/src/devices/gropdf/gropdf.pl
@@ -259,13 +259,14 @@ elsif (exists($ppsz{$papersz}))
     @address@hidden(0,0,$ppsz{$papersz}->[0],$ppsz{$papersz}->[1]);
 }
 
-my (@dt)=localtime(time);
+my (@dt)=localtime($ENV{SOURCE_DATE_EPOCH} || time);
 my $dt=PDFDate(address@hidden);
 
 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.1.man b/src/devices/grops/grops.1.man
index e7064d2..55b26f7 100644
--- a/src/devices/grops/grops.1.man
+++ b/src/devices/grops/grops.1.man
@@ -1423,6 +1423,13 @@ 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 1215100..86b2b9d 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 0000000..a410519
--- /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/curtime.cpp b/src/libs/libgroff/curtime.cpp
new file mode 100644
index 0000000..00821b7
--- /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/libs/libgroff/libgroff.am b/src/libs/libgroff/libgroff.am
index 78e3394..e215f2e 100644
--- a/src/libs/libgroff/libgroff.am
+++ b/src/libs/libgroff/libgroff.am
@@ -33,6 +33,7 @@ libgroff_a_SOURCES = \
   src/libs/libgroff/cmap.cpp \
   src/libs/libgroff/color.cpp \
   src/libs/libgroff/cset.cpp\
+  src/libs/libgroff/curtime.cpp \
   src/libs/libgroff/device.cpp \
   src/libs/libgroff/errarg.cpp \
   src/libs/libgroff/error.cpp \
diff --git a/src/roff/troff/input.cpp b/src/roff/troff/input.cpp
index 2d346d7..7cc2d91 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"
@@ -8080,7 +8081,7 @@ 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));