API: Add gdk_pixbuf_animation_new_from_stream()

1 files changed, 85 insertions, 0 deletions

diff --git a/gdk-pixbuf/gdk-pixbuf-animation.c b/gdk-pixbuf/gdk-pixbuf-animation.c
index e47a9f18d..60ef4a131 100644
--- a/gdk-pixbuf/gdk-pixbuf-animation.c
+++ b/gdk-pixbuf/gdk-pixbuf-animation.c
@@ -26,6 +26,7 @@
 #include <errno.h>
 #include "gdk-pixbuf-private.h"
 #include "gdk-pixbuf-animation.h"
+#include "gdk-pixbuf-loader.h"
 
 #include <glib/gstdio.h>
 
@@ -311,6 +312,90 @@ gdk_pixbuf_animation_new_from_file (const char *filename,
 #endif
 
 /**
+ * gdk_pixbuf_animation_new_from_stream:
+ * @stream:  a #GInputStream to load the pixbuf from
+ * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore
+ * @error: Return location for an error
+ *
+ * Creates a new animation by loading it from an input stream.
+ *
+ * The file format is detected automatically. If %NULL is returned, then 
+ * @error will be set. The @cancellable can be used to abort the operation
+ * from another thread. If the operation was cancelled, the error 
+ * %G_IO_ERROR_CANCELLED will be returned. Other possible errors are in 
+ * the #GDK_PIXBUF_ERROR and %G_IO_ERROR domains. 
+ *
+ * The stream is not closed.
+ *
+ * Return value: A newly-created pixbuf, or %NULL if any of several error 
+ * conditions occurred: the file could not be opened, the image format is 
+ * not supported, there was not enough memory to allocate the image buffer, 
+ * the stream contained invalid data, or the operation was cancelled.
+ *
+ * Since: 2.28
+ **/
+GdkPixbufAnimation *
+gdk_pixbuf_animation_new_from_stream  (GInputStream  *stream,
+                                       GCancellable  *cancellable,
+                                       GError       **error)
+{
+        GdkPixbufAnimation *animation;
+        GdkPixbufLoader *loader;
+        gssize n_read;
+        guchar buffer[LOAD_BUFFER_SIZE];
+        gboolean res;
+
+        g_return_val_if_fail (G_IS_INPUT_STREAM (stream), NULL);
+        g_return_val_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable), NULL);
+        g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+
+        loader = gdk_pixbuf_loader_new ();
+
+        res = TRUE;
+        while (1) { 
+                n_read = g_input_stream_read (stream, 
+                                              buffer, 
+                                              sizeof (buffer), 
+                                              cancellable, 
+                                              error);
+                if (n_read < 0) {
+                        res = FALSE;
+                        error = NULL; /* Ignore further errors */
+                        break;
+                }
+
+                if (n_read == 0)
+                        break;
+
+                if (!gdk_pixbuf_loader_write (loader, 
+                                              buffer, 
+                                              n_read, 
+                                              error)) {
+                        res = FALSE;
+                        error = NULL;
+                        break;
+                }
+        }
+
+        if (!gdk_pixbuf_loader_close (loader, error)) {
+                res = FALSE;
+                error = NULL;
+        }
+
+        if (res) {
+                animation = gdk_pixbuf_loader_get_animation (loader);
+                if (animation)
+                        g_object_ref (animation);
+        } else {
+                animation = NULL;
+        }
+
+        g_object_unref (loader);
+
+        return animation;
+}
+
+/**
  * gdk_pixbuf_animation_ref: (skip)
  * @animation: An animation.
  *