print: Use Poppler to render pages to print

.github/workflows/test.yml

@@ -15,6 +15,7 @@ jobs:
           apt-get update
           apt-get upgrade -y
           apt-get build-dep -y xdg-desktop-portal-gtk
+          apt-get install -y libpoppler-glib-dev
 
       - uses: actions/checkout@v2
 

configure.ac

@@ -109,6 +109,16 @@ if test x$enable_lockdown = xyes; then
 fi
 AM_CONDITIONAL([BUILD_LOCKDOWN],[test "$enable_lockdown" = "yes"])
 
+AC_ARG_ENABLE([poppler],
+              [AS_HELP_STRING([--enable-poppler],[Build pdftoraw portal. Needs libpoppler-glib])])
+AS_IF([test "x$enable_poppler" = "xyes"], [
+    PKG_CHECK_MODULES(POPPLER, [ gtk+-3.0 >= 3.14 gio-unix-2.0 poppler >= 0.16.7 poppler-glib >= 0.16.7 ])
+    AC_SUBST(POPPLER_CFLAGS)
+    AC_SUBST(POPPLER_LIBS)
+    AC_DEFINE([BUILD_POPPLER], [1], [Define to enable pdftoraw portal])
+])
+AM_CONDITIONAL([BUILD_POPPLER],[test "$enable_poppler" = "yes"])
+
 PKG_CHECK_MODULES(GTK, [xdg-desktop-portal >= 1.5 glib-2.0 >= 2.44 gio-unix-2.0 gtk+-3.0 >= 3.14 gtk+-unix-print-3.0])
 AC_SUBST(GTK_CFLAGS)
 AC_SUBST(GTK_LIBS)

src/Makefile.am.inc

@@ -260,6 +260,7 @@ xdg_desktop_portal_gtk_CPPFLAGS = \
 	-DLOCALEDIR=\"$(localedir)\"                    \
 	-I$(top_srcdir)/src				\
 	-I$(top_builddir)/src				\
+	-DLIBEXECDIR=\"$(libexecdir)\"                  \
 	$(NULL)
 
 noinst_PROGRAMS = \
@@ -285,3 +286,20 @@ testappchooser_SOURCES = \
 nodist_testappchooser_SOURCES = \
 	src/resources.c				\
 	$(NULL)
+
+if BUILD_POPPLER
+pdftoraw_SOURCES = \
+	src/pdftoraw.c \
+	$(NULL)
+
+pdftorawdir = $(libexecdir)/xdg-desktop-portal-gtk-utils
+pdftoraw_PROGRAMS = \
+	pdftoraw \
+	$(NULL)
+pdftoraw_LDADD = $(BASE_LIBS) $(POPPLER_LIBS) -lm
+pdftoraw_CFLAGS = $(BASE_CFLAGS) $(POPPLER_CFLAGS)
+pdftoraw_CPPFLAGS = \
+	-I$(top_srcdir)/src			\
+	-I$(top_builddir)/src			\
+	$(NULL)
+endif

src/pdftoraw.c

@@ -0,0 +1,208 @@
+/*
+ * Copyright (C) 2021 Thierry HUCHARD <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <unistd.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <gio/gio.h>
+#include <poppler.h>
+#include <gdk/gdk.h>
+
+
+// 1 inch = 72 points
+#define PTS 72.0
+
+// Resolution for the printer, 150 my choice
+#define DPI 150.0
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (PopplerDocument, g_object_unref);
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (PopplerPage, g_object_unref);
+
+static gchar *filename = "";
+static gboolean opt_test = FALSE;
+static gboolean opt_pages = FALSE;
+static int opt_raw = -1;
+static int opt_width = -1;
+static int opt_height = -1;
+
+static GOptionEntry entries[] = {
+  { "file", 'f', 0, G_OPTION_ARG_FILENAME, &filename, "PDF file path", NULL },
+  { "test", 't', 0, G_OPTION_ARG_NONE, &opt_test, "Test if the file is a PDF file", NULL },
+  { "pages", 'p', 0, G_OPTION_ARG_NONE, &opt_pages, "Returns the number of pages in the PDF file", NULL },
+  { "width", 'w', 0, G_OPTION_ARG_INT, &opt_width, "Give the size of the page provided in arguments", NULL},
+  { "height", 'W', 0, G_OPTION_ARG_INT, &opt_height, "Gives the height of the page provided in arguments", NULL},
+  { "raw", 'r', 0, G_OPTION_ARG_INT, &opt_raw, "Retrieves data in pixels from the page provided as arguments", NULL},
+  { NULL }
+};
+
+static int
+pdf_number_pages_get (PopplerDocument *doc)
+{
+    return poppler_document_get_n_pages (doc);
+}
+
+static void
+pdf_page_raw_get (PopplerDocument *doc,
+                 int page_nr)
+{
+    cairo_surface_t *s = NULL;
+    cairo_t *cr = NULL;
+    unsigned char *data = NULL;
+    g_autoptr (PopplerPage) page = NULL;
+    g_autoptr (GdkPixbuf) pix = NULL;
+    double width = 0;
+    double height = 0;
+    int w = 0;
+    int h = 0;
+
+    page = poppler_document_get_page (doc, page_nr);
+    if (page == NULL)
+    {
+       g_error("failure poppler_document_get_page");
+       return;
+    }
+    poppler_page_get_size (page, &width, &height);
+    width = DPI * width / PTS;
+    height = DPI * height / PTS;
+    w = (int)ceil(width);
+    h = (int)ceil(height);
+    s = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, w, h);
+    if (s == NULL)
+    {
+       g_error ("failure cairo_image_surface_create");
+       return;
+    }
+    cr = cairo_create (s);
+    if (cr == NULL)
+    {
+       cairo_surface_destroy (s);
+       g_error ("failure cairo_create");
+       return;
+    }
+    cairo_scale (cr, DPI / PTS, DPI / PTS);
+    cairo_save (cr);
+    poppler_page_render_for_printing (page, cr);
+    cairo_restore (cr);
+    pix = gdk_pixbuf_get_from_surface (s, 0, 0, w, h);
+    cairo_surface_destroy (s);
+    data = gdk_pixbuf_get_pixels (pix);
+    fwrite (data, 1, (w * h * 4), stdout);
+    cairo_destroy (cr);
+}
+
+static int
+pdf_page_width_get (PopplerDocument *doc,
+                   int page_nr)
+{
+    g_autoptr (PopplerPage) page = NULL;
+    double width = 0;
+    int w = 0;
+
+    page = poppler_document_get_page (doc, page_nr);
+    if (page == NULL)
+       return -1;
+    poppler_page_get_size (page, &width, NULL);
+    width = DPI * width / PTS;
+    w = (int)ceil (width);
+    return w;
+}
+
+static int
+pdf_page_height_get (PopplerDocument *doc,
+                    int page_nr)
+{
+    g_autoptr (PopplerPage) page = NULL;
+    double height = 0;
+    int h = 0;
+
+    page = poppler_document_get_page (doc, page_nr);
+    if (page == NULL)
+       return -1;
+    poppler_page_get_size (page, NULL, &height);
+    height = DPI * height / PTS;
+    h = (int)ceil (height);
+    return h;
+}
+
+int
+main (int argc, char **argv)
+{
+    g_autoptr (PopplerDocument) doc = NULL;
+    g_autoptr(GError) err = NULL;
+    g_autoptr (GFile) in = NULL;
+    g_autoptr (GOptionContext) context = NULL;
+    g_autofree char *help = NULL;
+
+    context = g_option_context_new ("- PDF utility for portal backends");
+    g_option_context_add_main_entries (context, entries, NULL);
+    if (!g_option_context_parse (context, &argc, &argv, &err))
+    {
+      g_printerr ("%s: %s", g_get_application_name (), err->message);
+      g_printerr ("\n");
+      g_printerr ("Try \"%s --help\" for more information.",
+                  g_get_prgname ());
+      g_printerr ("\n");
+      exit (EXIT_FAILURE);
+      return 1;
+    }
+
+    if (filename == NULL)
+    {
+	help = g_option_context_get_help (context, TRUE, NULL);
+        g_printerr ("%s", help);
+        exit (EXIT_FAILURE);
+    }
+    in = g_file_new_for_path (filename);
+    doc = poppler_document_new_from_gfile (in, NULL, NULL, &err);
+    if (err)
+    {
+	help = g_option_context_get_help (context, TRUE, NULL);
+        g_printerr ("%s", help);
+        exit (EXIT_FAILURE);
+    }
+
+    if (opt_test)
+    {
+        printf ("1");
+    }
+    else if (opt_raw > -1)
+    {
+        pdf_page_raw_get (doc, opt_raw);
+    }
+    else if (opt_pages)
+    {
+        printf ("%d", pdf_number_pages_get (doc));
+    }
+    else if (opt_width > -1)
+    {
+        printf ("%d", pdf_page_width_get (doc, opt_width));
+    }
+    else if (opt_height > -1)
+    {
+        printf ("%d", pdf_page_height_get (doc, opt_height));
+    }
+    else
+    {
+	help = g_option_context_get_help (context, TRUE, NULL);
+        g_printerr ("%s", help);
+        exit (EXIT_FAILURE);
+    }
+    return 0;
+}
+