Move reproducible-builds hack out of CairoRenderContext

3 files changed, 83 insertions, 45 deletions

diff --git a/src/extension/internal/cairo-render-context.cpp b/src/extension/internal/cairo-render-context.cpp
index 2b4072336..4464742dd 100644
--- a/src/extension/internal/cairo-render-context.cpp
+++ b/src/extension/internal/cairo-render-context.cpp
@@ -27,10 +27,7 @@
 
 
 #include <csignal>
-#include <climits>
 #include <cerrno>
-#include <ctime>
-#include <cstdlib>
 #include <2geom/pathvector.h>
 
 #include <glib.h>
@@ -814,12 +811,6 @@ CairoRenderContext::setupSurface(double width, double height)
     cairo_surface_t *surface = nullptr;
     cairo_matrix_t ctm;
     cairo_matrix_init_identity (&ctm);
-    char buffer[25];
-    char *endptr;
-    char *source_date_epoch;
-    time_t now;
-    struct tm *build_time;
-    unsigned long long epoch;
     switch (_target) {
         case CAIRO_SURFACE_TYPE_IMAGE:
             surface = cairo_image_surface_create(_target_format, (int)ceil(width), (int)ceil(height));
@@ -828,40 +819,6 @@ CairoRenderContext::setupSurface(double width, double height)
         case CAIRO_SURFACE_TYPE_PDF:
             surface = cairo_pdf_surface_create_for_stream(Inkscape::Extension::Internal::_write_callback, _stream, width, height);
             cairo_pdf_surface_restrict_to_version(surface, (cairo_pdf_version_t)_pdf_level);
-#if CAIRO_VERSION >= CAIRO_VERSION_ENCODE(1, 15, 4)
-            source_date_epoch = getenv("SOURCE_DATE_EPOCH");
-            if (source_date_epoch) {
-                errno = 0;
-                epoch = strtoull(source_date_epoch, &endptr, 10);
-                if ((errno == ERANGE && (epoch == ULLONG_MAX || epoch == 0))
-                        || (errno != 0 && epoch == 0)) {
-                    g_printerr ("Environment variable $SOURCE_DATE_EPOCH: strtoull: %s\n",
-                                strerror(errno));
-                    exit (1);
-                }
-                if (endptr == source_date_epoch) {
-                    g_printerr ("Environment variable $SOURCE_DATE_EPOCH: No digits were found: %s\n",
-                                endptr);
-                    exit (1);
-                }
-                if (*endptr != '\0') {
-                    g_printerr ("Environment variable $SOURCE_DATE_EPOCH: Trailing garbage: %s\n",
-                                endptr);
-                    exit (1);
-                }
-                if (epoch > ULONG_MAX) {
-                    g_printerr ("Environment variable $SOURCE_DATE_EPOCH: must be <= %lu but saw: %llu\n",
-                                ULONG_MAX, epoch);
-                    exit (1);
-                }
-                now = (time_t)epoch;
-                build_time = gmtime(&now);
-                strftime(buffer, 25, "%Y-%m-%dT%H:%M:%S%z", build_time);
-                cairo_pdf_surface_set_metadata (surface,
-                                                CAIRO_PDF_METADATA_CREATE_DATE,
-                                                buffer);
-            }
-#endif
             break;
 #endif
 #ifdef CAIRO_HAS_PS_SURFACE
@@ -957,6 +914,12 @@ CairoRenderContext::_setSurfaceMetadata(cairo_surface_t *surface)
             if (!_metadata.creator.empty()) {
                 cairo_pdf_surface_set_metadata(surface, CAIRO_PDF_METADATA_CREATOR, _metadata.creator.c_str());
             }
+            if (!_metadata.cdate.empty()) {
+                cairo_pdf_surface_set_metadata(surface, CAIRO_PDF_METADATA_CREATE_DATE, _metadata.cdate.c_str());
+            }
+            if (!_metadata.mdate.empty()) {
+                cairo_pdf_surface_set_metadata(surface, CAIRO_PDF_METADATA_MOD_DATE, _metadata.mdate.c_str());
+            }
             break;
 #endif
 #if defined CAIRO_HAS_PS_SURFACE
diff --git a/src/extension/internal/cairo-renderer.cpp b/src/extension/internal/cairo-renderer.cpp
index 35531cb04..170abe9a7 100644
--- a/src/extension/internal/cairo-renderer.cpp
+++ b/src/extension/internal/cairo-renderer.cpp
@@ -61,6 +61,8 @@
 
 #include "io/sys.h"
 
+#include "include/source_date_epoch.h"
+
 #include "libnrtype/Layout-TNG.h"
 
 #include "object/sp-anchor.h"
@@ -697,8 +699,13 @@ void CairoRenderer::setMetadata(CairoRenderContext *ctx, SPDocument *doc) {
     ctx->_metadata.creator = Glib::ustring::compose("Inkscape %1 (https://inkscape.org)",
                                                     Inkscape::version_string_without_revision);
 
-   // cdate / mdate
-   // (currently unused)
+    // cdate (only used for for reproducible builds hack)
+    Glib::ustring cdate = ReproducibleBuilds::now_iso_8601();
+    if (!cdate.empty()) {
+        ctx->_metadata.cdate = cdate;
+    }
+
+    // mdate (currently unused)
 }
 
 bool
diff --git a/src/include/source_date_epoch.h b/src/include/source_date_epoch.h
new file mode 100644
index 000000000..9080526f7
--- /dev/null
+++ b/src/include/source_date_epoch.h
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/** @file
+ * Functions to parse the "SOURCE_DATE_EPOCH" environment variable for reproducible build hacks, see
+ *     https://reproducible-builds.org/docs/source-date-epoch/
+ *//*
+ * Authors:
+ *   Patrick Storz <eduard.braun2@gmx.de>
+ *
+ * Copyright (C) 2019 Authors
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_SOURCE_DATE_EPOCH
+#define SEEN_SOURCE_DATE_EPOCH
+
+#include <sstream>
+#include <iostream>
+#include <cstdlib>
+#include <ctime>
+
+namespace ReproducibleBuilds {
+
+/** parse current time from SOURCE_DATE_EPOCH environment variable
+ *
+ *  \return current time (or zero if SOURCE_DATE_EPOCH unset)
+ */
+time_t now()
+{
+    time_t now = 0;
+
+    char *source_date_epoch = std::getenv("SOURCE_DATE_EPOCH");
+    if (source_date_epoch) {
+        std::istringstream iss(source_date_epoch);
+        iss >> now;
+        if (iss.fail() || !iss.eof()) {
+            std::cerr << "Error: Cannot parse SOURCE_DATE_EPOCH as integer\n";
+            exit(27);
+        }
+    }
+
+    return now;
+}
+
+/** like ReproducibleBuilds::now() but returns a ISO 8601 formatted string
+ *
+ *  \return current time as ISO 8601 formatted string (or empty string if SOURCE_DATE_EPOCH unset)
+ */
+Glib::ustring now_iso_8601()
+{
+    Glib::ustring now_formatted;
+
+    time_t now = ReproducibleBuilds::now();
+    if (now) {
+        const tm *now_struct;
+        char buffer[25];
+
+        now_struct = gmtime(&now);
+        if (strftime(buffer, 25, "%Y-%m-%dT%H:%M:%S", now_struct)) {
+            now_formatted = buffer;
+        }
+    }
+
+    return now_formatted;
+}
+
+} // namespace ReproducibleBuilds
+
+#endif // SEEN_SOURCE_DATE_EPOCH