[gimp/gimp-2-10] plug-ins: clean up a bit file-pdf-save.

[Jehan <jehanp src gnome org>]

commit ecd86145e0f44befbb073024e6e58d610499058d
Author: Jehan <jehan girinstud io>
Date:   Thu Jul 11 23:55:51 2019 +0200

    plug-ins: clean up a bit file-pdf-save.
    
    This improves commit bbd5ebbe8a. Several parameters did not need to go
    inside draw_layer(). In particular this function should not take care of
    filling return values on errors. It should just return a success boolean
    with a GError which is processed on the main function. This also allows
    proper shortcut to end the loop earlier on the first error.
    Also the layer index parameter does not need to be a pointer since it
    never requires updates.
    Finally declare variables in smaller scopes for cleaner code.
    
    (cherry picked from commit 5b2d89f794e12b2e4538976cd24a1baaa371137e)

 plug-ins/common/file-pdf-save.c | 127 ++++++++++++++++++----------------------
 1 file changed, 58 insertions(+), 69 deletions(-)
---
diff --git a/plug-ins/common/file-pdf-save.c b/plug-ins/common/file-pdf-save.c
index 3eae429182..aa2c98ccea 100644
--- a/plug-ins/common/file-pdf-save.c
+++ b/plug-ins/common/file-pdf-save.c
@@ -260,18 +260,14 @@ static void              drawText                   (gint32           text_id,
                                                      gdouble          x_res,
                                                      gdouble          y_res);
 
-static void              draw_layer                  (gint32               *layers,
-                                                      gint                  n_layers,
-                                                      gint                 *j,
-                                                      gint                 *nreturn_vals,
-                                                      cairo_surface_t      *pdf_file,
-                                                      cairo_t              *cr,
-                                                      FILE                 *fp,
-                                                       GimpParam           *values,
-                                                      gdouble               x_res,
-                                                      gdouble               y_res,
-                                                      const gchar          *name,
-                                                      GError               *error);
+static gboolean          draw_layer                 (gint32          *layers,
+                                                     gint             n_layers,
+                                                     gint             j,
+                                                     cairo_t         *cr,
+                                                     gdouble          x_res,
+                                                     gdouble          y_res,
+                                                     const gchar     *name,
+                                                     GError         **error);
 
 static gboolean     dnd_remove = TRUE;
 static PdfMultiPage multi_page;
@@ -593,7 +589,21 @@ run (const gchar      *name,
       /* Now, we should loop over the layers of each image */
       for (j = 0; j < n_layers; j++)
         {
-          draw_layer (layers, n_layers, &j, nreturn_vals, pdf_file, cr, fp, values, x_res, y_res, name, 
error);
+          if (! draw_layer (layers, n_layers, j, cr, x_res, y_res, name, &error))
+            {
+              *nreturn_vals = 2;
+
+              /* free the resources */
+              cairo_surface_destroy (pdf_file);
+              cairo_destroy (cr);
+              fclose (fp);
+
+              values[0].data.d_status = GIMP_PDB_EXECUTION_ERROR;
+
+              values[1].type          = GIMP_PDB_STRING;
+              values[1].data.d_string = error->message;
+              return;
+            }
         }
 
       /* We are done with this image - Show it!
@@ -1651,68 +1661,57 @@ drawText (gint32    text_id,
   cairo_restore (cr);
 }
 
-static void draw_layer (gint32               *layers,
-                        gint                  n_layers,
-                        gint                 *j,
-                        gint                 *nreturn_vals,
-                        cairo_surface_t      *pdf_file,
-                        cairo_t              *cr,
-                        FILE                 *fp,
-                        GimpParam            *values,
-                        gdouble               x_res,
-                        gdouble               y_res,
-                        const gchar          *name,
-                        GError               *error)
+static gboolean
+draw_layer (gint32       *layers,
+            gint          n_layers,
+            gint          j,
+            cairo_t      *cr,
+            gdouble       x_res,
+            gdouble       y_res,
+            const gchar  *name,
+            GError      **error)
 {
-  gint32           layer_ID;
-  gint32           mask_ID    = -1;
-  cairo_surface_t *mask_image = NULL;
-  gdouble          opacity;
-  gboolean         single_color;
-  gint             x, y, i;
-  gint             children_num;
-  gint            *children;
+  gint32 layer_ID;
 
   if (optimize.reverse_order && optimize.layers_as_pages)
-    layer_ID = layers [*j];
+    layer_ID = layers [j];
   else
-    layer_ID = layers [n_layers - *j - 1];
+    layer_ID = layers [n_layers - j - 1];
 
   if (gimp_item_is_group (layer_ID))
     {
+      gint *children;
+      gint  children_num;
+      gint  i;
+
       children = gimp_item_get_children (layer_ID, &children_num);
       for (i = 0; i < children_num; i++)
         {
-          draw_layer (children, children_num, &i, nreturn_vals, pdf_file, cr, fp, values, x_res, y_res, 
name, error);
+          if (! draw_layer (children, children_num, i,
+                            cr, x_res, y_res, name, error))
+            return FALSE;
         }
     }
   else
     {
+      cairo_surface_t *mask_image = NULL;
+      gint32           mask_ID    = -1;
+      gdouble          opacity;
+
       opacity = gimp_layer_get_opacity (layer_ID) / 100.0;
 
       if ((gimp_item_get_visible (layer_ID) && opacity > 0.0) ||
           ! optimize.ignore_hidden)
         {
+          gint x, y;
+
           mask_ID = gimp_layer_get_mask (layer_ID);
           if (mask_ID != -1)
             {
-              mask_image = get_cairo_surface (mask_ID, TRUE,
-                                              &error);
-              if (error != NULL)
-                {
-                  *nreturn_vals = 2;
-
-                  /* free the resources */
-                  cairo_surface_destroy (pdf_file);
-                  cairo_destroy (cr);
-                  fclose (fp);
-
-                  values[0].data.d_status = GIMP_PDB_EXECUTION_ERROR;
+              mask_image = get_cairo_surface (mask_ID, TRUE, error);
 
-                  values[1].type          = GIMP_PDB_STRING;
-                  values[1].data.d_string = error->message;
-                  return;
-                }
+              if (*error)
+                return FALSE;
             }
           gimp_drawable_offsets (layer_ID, &x, &y);
 
@@ -1720,7 +1719,8 @@ static void draw_layer (gint32               *layers,
             {
               /* For raster layers */
 
-              GimpRGB layer_color;
+              GimpRGB  layer_color;
+              gboolean single_color = FALSE;
 
               layer_color = get_layer_color (layer_ID, &single_color);
 
@@ -1744,23 +1744,10 @@ static void draw_layer (gint32               *layers,
                 {
                   cairo_surface_t *layer_image;
 
-                  layer_image = get_cairo_surface (layer_ID, FALSE,
-                                                   &error);
-                  if (error != NULL)
-                    {
-                      *nreturn_vals = 2;
-
-                      /* free the resources */
-                      cairo_surface_destroy (pdf_file);
-                      cairo_destroy (cr);
-                      fclose (fp);
-
-                      values[0].data.d_status = GIMP_PDB_EXECUTION_ERROR;
+                  layer_image = get_cairo_surface (layer_ID, FALSE, error);
 
-                      values[1].type          = GIMP_PDB_STRING;
-                      values[1].data.d_string = error->message;
-                      return;
-                    }
+                  if (*error)
+                    return FALSE;
 
                   cairo_clip (cr);
 
@@ -1793,4 +1780,6 @@ static void draw_layer (gint32               *layers,
       if (mask_ID != -1)
         cairo_surface_destroy (mask_image);
     }
+
+  return TRUE;
 }