[gdk-pixbuf] loaders: Remove "error && *error == NULL" checks

[Bastien Nocera <hadess src gnome org>]

commit 3b76db03bdd9c1cbc31a2bb812b24d0e7abdb5c9
Author: Bastien Nocera <hadess hadess net>
Date:   Thu Jul 13 18:53:26 2017 +0200

    loaders: Remove "error && *error == NULL" checks
    
    g_set_error() and friends already do those checks.

 gdk-pixbuf/io-bmp.c  |   10 +++-----
 gdk-pixbuf/io-jpeg.c |   26 ++++++++++--------------
 gdk-pixbuf/io-png.c  |   51 +++++++++++++++++++------------------------------
 3 files changed, 35 insertions(+), 52 deletions(-)
---
diff --git a/gdk-pixbuf/io-bmp.c b/gdk-pixbuf/io-bmp.c
index 6460e7f..9ba3597 100644
--- a/gdk-pixbuf/io-bmp.c
+++ b/gdk-pixbuf/io-bmp.c
@@ -746,12 +746,10 @@ static gboolean gdk_pixbuf__bmp_image_stop_load(gpointer data, GError **error)
                g_object_unref(context->pixbuf);
 
        if (context->read_state == READ_STATE_HEADERS) {
-                if (error && *error == NULL) {
-                        g_set_error_literal (error,
-                                             GDK_PIXBUF_ERROR,
-                                             GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
-                                             _("Premature end-of-file encountered"));
-                }
+                g_set_error_literal (error,
+                                     GDK_PIXBUF_ERROR,
+                                     GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
+                                     _("Premature end-of-file encountered"));
                retval = FALSE;
        }
        
diff --git a/gdk-pixbuf/io-jpeg.c b/gdk-pixbuf/io-jpeg.c
index 1c0eba1..05ca959 100644
--- a/gdk-pixbuf/io-jpeg.c
+++ b/gdk-pixbuf/io-jpeg.c
@@ -701,14 +701,12 @@ gdk_pixbuf__jpeg_image_load (FILE *f, GError **error)
                    default:
                      g_object_unref (pixbuf);
                      pixbuf = NULL;
-                     if (error && *error == NULL) {
-                        g_set_error (error,
-                                     GDK_PIXBUF_ERROR,
-                                    GDK_PIXBUF_ERROR_UNKNOWN_TYPE,
-                                    _("Unsupported JPEG color space (%s)"),
-                                    colorspace_name (cinfo.out_color_space)); 
-                     }
-                             goto out; 
+                      g_set_error (error,
+                                   GDK_PIXBUF_ERROR,
+                                  GDK_PIXBUF_ERROR_UNKNOWN_TYPE,
+                                  _("Unsupported JPEG color space (%s)"),
+                                  colorspace_name (cinfo.out_color_space));
+                     goto out;
                }
        }
 
@@ -914,13 +912,11 @@ gdk_pixbuf__jpeg_image_load_lines (JpegProgContext  *context,
                         convert_cmyk_to_rgb (cinfo, lines);
                         break;
                 default:
-                        if (error && *error == NULL) {
-                                g_set_error (error,
-                                             GDK_PIXBUF_ERROR,
-                                             GDK_PIXBUF_ERROR_UNKNOWN_TYPE,
-                                             _("Unsupported JPEG color space (%s)"),
-                                             colorspace_name (cinfo->out_color_space));
-                        }
+                        g_set_error (error,
+                                     GDK_PIXBUF_ERROR,
+                                     GDK_PIXBUF_ERROR_UNKNOWN_TYPE,
+                                     _("Unsupported JPEG color space (%s)"),
+                                     colorspace_name (cinfo->out_color_space));
 
                         return FALSE;
                 }
diff --git a/gdk-pixbuf/io-png.c b/gdk-pixbuf/io-png.c
index 759e78a..72bd78a 100644
--- a/gdk-pixbuf/io-png.c
+++ b/gdk-pixbuf/io-png.c
@@ -312,13 +312,10 @@ gdk_pixbuf__png_image_load (FILE *f, GError **error)
         pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, ctype & PNG_COLOR_MASK_ALPHA, 8, w, h);
 
        if (!pixbuf) {
-                if (error && *error == NULL) {
-                        g_set_error_literal (error,
-                                             GDK_PIXBUF_ERROR,
-                                             GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
-                                             _("Insufficient memory to load PNG file"));
-                }
-                
+                g_set_error_literal (error,
+                                     GDK_PIXBUF_ERROR,
+                                     GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
+                                     _("Insufficient memory to load PNG file"));
 
                png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
                return NULL;
@@ -526,11 +523,9 @@ gdk_pixbuf__png_image_stop_load (gpointer context, GError **error)
         if (lc->pixbuf)
                 g_object_unref (lc->pixbuf);
         else {
-                if (error && *error == NULL) {
-                        g_set_error_literal (error, GDK_PIXBUF_ERROR,
-                                             GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
-                                             _("Premature end-of-file encountered"));
-                }
+                g_set_error_literal (error, GDK_PIXBUF_ERROR,
+                                     GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
+                                     _("Premature end-of-file encountered"));
                 retval = FALSE;
        }
         
@@ -665,12 +660,10 @@ png_info_callback   (png_structp png_read_ptr,
                 
                 if (w == 0 || h == 0) {
                         lc->fatal_error_occurred = TRUE;
-                        if (lc->error && *lc->error == NULL) {
-                                g_set_error_literal (lc->error,
-                                                     GDK_PIXBUF_ERROR,
-                                                     GDK_PIXBUF_ERROR_FAILED,
-                                                     _("Transformed PNG has zero width or height."));
-                        }
+                        g_set_error_literal (lc->error,
+                                             GDK_PIXBUF_ERROR,
+                                             GDK_PIXBUF_ERROR_FAILED,
+                                             _("Transformed PNG has zero width or height."));
                         return;
                 }
         }
@@ -680,13 +673,11 @@ png_info_callback   (png_structp png_read_ptr,
         if (lc->pixbuf == NULL) {
                 /* Failed to allocate memory */
                 lc->fatal_error_occurred = TRUE;
-                if (lc->error && *lc->error == NULL) {
-                        g_set_error (lc->error,
-                                     GDK_PIXBUF_ERROR,
-                                     GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
-                                     _("Insufficient memory to store a %lu by %lu image; try exiting some 
applications to reduce memory usage"),
-                                     (gulong) width, (gulong) height);
-                }
+                g_set_error (lc->error,
+                             GDK_PIXBUF_ERROR,
+                             GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
+                             _("Insufficient memory to store a %lu by %lu image; try exiting some 
applications to reduce memory usage"),
+                             (gulong) width, (gulong) height);
                 return;
         }
 
@@ -758,12 +749,10 @@ png_row_callback   (png_structp png_read_ptr,
 
         if (row_num >= lc->pixbuf->height) {
                 lc->fatal_error_occurred = TRUE;
-                if (lc->error && *lc->error == NULL) {
-                        g_set_error_literal (lc->error,
-                                             GDK_PIXBUF_ERROR,
-                                             GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
-                                             _("Fatal error reading PNG image file"));
-                }
+                g_set_error_literal (lc->error,
+                                     GDK_PIXBUF_ERROR,
+                                     GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
+                                     _("Fatal error reading PNG image file"));
                 return;
         }