From c5e3ce44081a5059375d0211c07e0e3579544a94 Mon Sep 17 00:00:00 2001
From: John Cupitt <jcupitt@gmail.com>
Date: Thu, 21 Jan 2010 17:04:00 +0000
Subject: [PATCH] stuff

---
 ChangeLog                   |  2 ++
 TODO                        |  7 ++++-
 libvips/iofuncs/buffer.c    | 56 ++++++++++++++++++++++++++++++++++---
 libvips/iofuncs/im_close.c  |  7 +++--
 libvips/iofuncs/im_open.c   |  6 ++--
 libvips/iofuncs/im_render.c |  6 ++--
 6 files changed, 71 insertions(+), 13 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 209f1163..a0ee3a7b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -19,6 +19,8 @@
 - better TIFF YCbCr reading (thanks Ole)
 - isanalyze generates fewer silly error messages
 - added "written" callbacks, used to implement write to non-vips formats
+- "invalidate" is careful to keep images alive, so invalidate callbacks can do
+  im_close()
 
 26/11/09 started 7.20.3
 - updated en_GB.po translation 
diff --git a/TODO b/TODO
index 277cb807..97843671 100644
--- a/TODO
+++ b/TODO
@@ -1,4 +1,9 @@
-- test new floodfill in paintbox
+- close callbacks could use invalidate's trick and give close callbacks more
+  safety
+
+  could get rid of a couple of image flags too
+
+- flood blob with ink == initial click loops
 
 - we sill have the old flood-fill code there, move to deprecated
 
diff --git a/libvips/iofuncs/buffer.c b/libvips/iofuncs/buffer.c
index d41451a9..c67b738f 100644
--- a/libvips/iofuncs/buffer.c
+++ b/libvips/iofuncs/buffer.c
@@ -559,16 +559,50 @@ im_invalidate_region( REGION *reg )
 }
 
 static void *
-im_invalidate_image( IMAGE *im )
+im_invalidate_image( IMAGE *im, GSList **to_be_invalidated )
 {
 	(void) im_slist_map2( im->regions,
 		(VSListMap2Fn) im_invalidate_region, NULL, NULL );
-	if( im__trigger_callbacks( im->invalidatefns ) )
-		return( im );
+
+	*to_be_invalidated = g_slist_prepend( *to_be_invalidated, im );
 
 	return( NULL );
 }
 
+/* Trigger a callbacks on a list of images, where the callbacks might create
+ * or destroy the images.
+ *
+ * We make a set of temp regions to hold the images open, but when we switch
+ * to VipsObject we should incr/decr ref count.
+ */
+static void
+im_invalidate_trigger( GSList *images )
+{
+	GSList *regions;
+	GSList *p;
+
+	regions = NULL;
+	for( p = images; p; p = p->next ) {
+		IMAGE *im = (IMAGE *) p->data;
+
+		regions = g_slist_prepend( regions, im_region_create( im ) );
+	}
+
+	for( p = images; p; p = p->next ) {
+		IMAGE *im = (IMAGE *) p->data;
+
+		(void) im__trigger_callbacks( im->invalidatefns );
+	}
+
+	for( p = regions; p; p = p->next ) {
+		REGION *r = (REGION *) p->data;
+
+		im_region_free( r );
+	}
+
+	g_slist_free( regions );
+}
+
 /**
  * im_invalidate:
  * @im: #IMAGE to invalidate
@@ -581,8 +615,22 @@ im_invalidate_image( IMAGE *im )
 void
 im_invalidate( IMAGE *im )
 {
+	GSList *to_be_invalidated;
+
+	/* Invalidate callbacks might do anything, including removing images
+	 * or invalidating other images, so we can't trigger them from within 
+	 * the image loop. Instead we collect a list of image to invalidate 
+	 * and trigger them all in one go, checking that they are not
+	 * invalidated.
+	 */
+	to_be_invalidated = NULL;
 	(void) im__link_map( im, 
-		(VSListMap2Fn) im_invalidate_image, NULL, NULL );
+		(VSListMap2Fn) im_invalidate_image, &to_be_invalidated, NULL );
+
+	im_invalidate_trigger( to_be_invalidated );
+
+	g_slist_free( to_be_invalidated );
+
 }
 
 /* Init the buffer cache system.
diff --git a/libvips/iofuncs/im_close.c b/libvips/iofuncs/im_close.c
index e428771a..3ab462bf 100644
--- a/libvips/iofuncs/im_close.c
+++ b/libvips/iofuncs/im_close.c
@@ -276,9 +276,10 @@ im_close( IMAGE *im )
 		 * be closed when the last region is freed 
 		 * (see im_region_free()). 
 		 */
-#ifdef DEBUG_IO
-		printf( "im_close: pending close for \"%s\"\n", im->filename );
-#endif /*DEBUG_IO*/
+#ifdef DEBUG_NEW
+		printf( "im_close: pending close for 0x%p, \"%s\"\n", 
+			im, im->filename );
+#endif /*DEBUG_NEW*/
 
 		im->close_pending = 1;
 	}
diff --git a/libvips/iofuncs/im_open.c b/libvips/iofuncs/im_open.c
index 2c0cfdf5..2ed70d6e 100644
--- a/libvips/iofuncs/im_open.c
+++ b/libvips/iofuncs/im_open.c
@@ -125,7 +125,7 @@ Modified:
  */
 
 /*
-#define DEBUG_IO
+#define DEBUG
  */
 
 #ifdef HAVE_CONFIG_H
@@ -501,9 +501,9 @@ im_open( const char *filename, const char *mode )
 			(im_callback_fn) evalend_cb, progress, NULL );
 	}
 
-#ifdef DEBUG_IO
+#ifdef DEBUG
 	printf( "im_open: success for %s (%p)\n", im->filename, im );
-#endif /*DEBUG_IO*/
+#endif /*DEBUG*/
 
 	return( im );
 }
diff --git a/libvips/iofuncs/im_render.c b/libvips/iofuncs/im_render.c
index c3a6a322..14036a06 100644
--- a/libvips/iofuncs/im_render.c
+++ b/libvips/iofuncs/im_render.c
@@ -1079,11 +1079,13 @@ im_render_priority( IMAGE *in, IMAGE *out, IMAGE *mask,
 	if( render_thread_create() )
 		return( -1 );
 
-	if( width <= 0 || height <= 0 || max < -1 ) {
+	if( width <= 0 || 
+		height <= 0 || 
+		max < -1 ) {
 		im_error( "im_render", "%s", _( "bad parameters" ) );
 		return( -1 );
 	}
-	if( im_pincheck( in ) || im_poutcheck( out ) )
+	if( im_piocheck( in, out ) )
 		return( -1 );
 	if( mask ) {
 		if( im_poutcheck( mask ) ||