[libgxps] Add g_return macros missing in some public methods

[Carlos Garcia Campos <carlosgc src gnome org>]

commit 6e7f23b72fa6ffab794cc2956af7d59700318a77
Author: Carlos Garcia Campos <carlosgc gnome org>
Date:   Sat Oct 8 17:41:00 2011 +0200

    Add g_return macros missing in some public methods

 libgxps/gxps-file.c  |    3 +++
 libgxps/gxps-links.c |   15 +++++++++++++++
 libgxps/gxps-page.c  |    6 ++++++
 3 files changed, 24 insertions(+), 0 deletions(-)
---
diff --git a/libgxps/gxps-file.c b/libgxps/gxps-file.c
index bbb1d9c..a08028e 100644
--- a/libgxps/gxps-file.c
+++ b/libgxps/gxps-file.c
@@ -459,6 +459,9 @@ gxps_file_get_document_for_link_target (GXPSFile       *xps,
 	guint        n_doc = 0;
 	const gchar *uri;
 
+        g_return_val_if_fail (GXPS_IS_FILE (xps), -1);
+        g_return_val_if_fail (target != NULL, -1);
+
 	uri = gxps_link_target_get_uri (target);
 	for (l = xps->priv->docs; l; l = g_list_next (l)) {
 		if (g_ascii_strcasecmp (uri, (gchar *)l->data) == 0)
diff --git a/libgxps/gxps-links.c b/libgxps/gxps-links.c
index 1e9d48b..0fff0da 100644
--- a/libgxps/gxps-links.c
+++ b/libgxps/gxps-links.c
@@ -73,6 +73,8 @@ gxps_link_copy (GXPSLink *link)
 {
 	GXPSLink *link_copy;
 
+        g_return_val_if_fail (link != NULL, NULL);
+
 	link_copy = g_slice_new (GXPSLink);
 	*link_copy = *link;
 
@@ -109,6 +111,8 @@ gxps_link_free (GXPSLink *link)
 GXPSLinkTarget *
 gxps_link_get_target (GXPSLink *link)
 {
+        g_return_val_if_fail (link != NULL, NULL);
+
 	return link->target;
 }
 
@@ -124,6 +128,9 @@ void
 gxps_link_get_area (GXPSLink          *link,
 		    cairo_rectangle_t *area)
 {
+        g_return_if_fail (link != NULL);
+        g_return_if_fail (area != NULL);
+
 	*area = link->area;
 }
 
@@ -141,6 +148,8 @@ gxps_link_target_copy (GXPSLinkTarget *target)
 {
 	GXPSLinkTarget *target_copy;
 
+        g_return_val_if_fail (target != NULL, NULL);
+
 	target_copy = g_slice_new (GXPSLinkTarget);
 
 	target_copy->is_internal = target->is_internal;
@@ -179,6 +188,8 @@ gxps_link_target_free (GXPSLinkTarget *target)
 gboolean
 gxps_link_target_is_internal (GXPSLinkTarget *target)
 {
+        g_return_val_if_fail (target != NULL, FALSE);
+
 	return target->is_internal;
 }
 
@@ -196,6 +207,8 @@ gxps_link_target_is_internal (GXPSLinkTarget *target)
 const gchar *
 gxps_link_target_get_anchor (GXPSLinkTarget *target)
 {
+        g_return_val_if_fail (target != NULL, NULL);
+
 	return target->anchor;
 }
 
@@ -210,6 +223,8 @@ gxps_link_target_get_anchor (GXPSLinkTarget *target)
 const gchar *
 gxps_link_target_get_uri (GXPSLinkTarget *target)
 {
+        g_return_val_if_fail (target != NULL, NULL);
+
 	return target->uri;
 }
 
diff --git a/libgxps/gxps-page.c b/libgxps/gxps-page.c
index 4efa196..aef57e6 100644
--- a/libgxps/gxps-page.c
+++ b/libgxps/gxps-page.c
@@ -3479,6 +3479,8 @@ gxps_page_get_links (GXPSPage *page,
 	GList            *links;
 	cairo_rectangle_t extents;
 
+        g_return_val_if_fail (GXPS_IS_PAGE (page), NULL);
+
 	extents.x = extents.y = 0;
 	extents.width = page->priv->width;
 	extents.height = page->priv->height;
@@ -3515,6 +3517,10 @@ gxps_page_get_anchor_destination (GXPSPage          *page,
 {
 	cairo_rectangle_t *anchor_area;
 
+        g_return_val_if_fail (GXPS_IS_PAGE (page), FALSE);
+        g_return_val_if_fail (anchor != NULL, FALSE);
+        g_return_val_if_fail (area != NULL, FALSE);
+
 	if (!page->priv->has_anchors)
 		return FALSE;