Add low memory handler to purge unused slabs on OS3

TODO: find some way to purge NetSurf's memory cache safely from another process

3 files changed, 43 insertions, 1 deletions

diff --git a/frontends/amiga/gui.c b/frontends/amiga/gui.c
index e5b5c597c..6dca47a05 100644
--- a/frontends/amiga/gui.c
+++ b/frontends/amiga/gui.c
@@ -5543,6 +5543,11 @@ int main(int argc, char** argv)
 	/* Open splash window */
 	Object *splash_window = ami_gui_splash_open();
 
+#ifndef __amigaos4__
+	/* OS3 low memory handler */
+	struct Interupt *memhandler = ami_memory_init();
+#endif
+
 	ami_object_init();
 
 	if (ami_open_resources() == false) { /* alloc message ports */
@@ -5743,6 +5748,11 @@ int main(int argc, char** argv)
 	ami_object_fini();
 	ami_bitmap_fini();
 
+#ifndef __amigaos4__
+	/* OS3 low memory handler */
+	ami_memory_fini(memhandler);
+#endif
+
 	LOG("Closing screen");
 	ami_gui_close_screen(scrn, locked_screen, FALSE);
 	if(nsscreentitle) FreeVec(nsscreentitle);
diff --git a/frontends/amiga/memory.c b/frontends/amiga/memory.c
index d86f73d74..abf849db6 100755
--- a/frontends/amiga/memory.c
+++ b/frontends/amiga/memory.c
@@ -17,8 +17,11 @@
  */
 
 #ifndef __amigaos4__
+#include <proto/exec.h>
+#include <exec/interrupts.h>
 #include <stdlib.h>
 #include "amiga/memory.h"
+#include "amiga/os3support.h"
 #include "utils/log.h"
 
 ULONG __slab_max_size = 2048; /* Enable clib2's slab allocator */
@@ -60,5 +63,32 @@ void ami_memory_slab_dump(void)
 {
 	__get_slab_usage(ami_memory_slab_callback);
 }
+
+static ASM ULONG ami_memory_handler(REG(a0, struct MemHandlerData *mhd), REG(a1, void *userdata), REG(a6, struct ExecBase *execbase))
+{
+	__free_unused_slabs();
+
+	return MEM_ALL_DONE;
+}
+ 
+struct Interrupt *ami_memory_init(void)
+{
+	struct Interrupt *memhandler = malloc(sizeof(struct Interrupt));
+
+	memhandler->is_Node.ln_Pri = 1;
+	memhandler->is_Node.ln_Name = "NetSurf slab memory handler";
+	memhandler->is_Data = NULL;
+	memhandler->is_Code = (APTR)&ami_memory_handler;
+	AddMemHandler(memhandler);
+
+	return memhandler;
+}
+
+void ami_memory_fini(struct Interrupt *memhandler)
+{
+	RemMemHandler(memhandler);
+	free(memhandler);
+}
+
 #endif
 
diff --git a/frontends/amiga/memory.h b/frontends/amiga/memory.h
index 3d9235062..a87a3ea97 100644
--- a/frontends/amiga/memory.h
+++ b/frontends/amiga/memory.h
@@ -57,9 +57,11 @@ void *ami_memory_clear_alloc(size_t size, UBYTE value);
 #define ami_memory_itempool_free(p,i,s) FreePooled(p,i,s)
 #endif
 
-/* clib2 slab allocator stats */
+/* clib2 slab allocator */
 #ifndef __amigaos4__
 void ami_memory_slab_dump(void);
+struct Interrupt *ami_memory_init(void);
+void ami_memory_fini(struct Interrupt *memhandler);
 #endif
 
 #endif //AMIGA_MEMORY_H