* Boston, MA 02111-1307, USA.
*/
#include <config.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <unistd.h>
#include "girffi.h"
+#include "girepository.h"
ffi_type *
g_ir_ffi_get_ffi_type (GITypeTag tag)
return NULL;
}
+
+/**
+ * g_callable_info_get_ffi_arg_types:
+ * @callable_info: a callable info from a typelib
+ *
+ * Return value: an array of ffi_type*. The array itself
+ * should be freed using g_free() after use.
+ */
+ffi_type **
+g_callable_info_get_ffi_arg_types (GICallableInfo *callable_info)
+{
+ ffi_type **arg_types;
+ gint n_args, i;
+
+ g_return_val_if_fail (callable_info != NULL, NULL);
+
+ n_args = g_callable_info_get_n_args (callable_info);
+
+ arg_types = (ffi_type **) g_new0 (ffi_type *, n_args + 1);
+
+ for (i = 0; i < n_args; ++i)
+ {
+ GIArgInfo *arg_info = g_callable_info_get_arg (callable_info, i);
+ GITypeInfo *arg_type = g_arg_info_get_type (arg_info);
+ GITypeTag type_tag = g_type_info_get_tag (arg_type);
+ arg_types[i] = g_ir_ffi_get_ffi_type (type_tag);
+ g_base_info_unref ((GIBaseInfo *)arg_info);
+ g_base_info_unref ((GIBaseInfo *)arg_type);
+ }
+ arg_types[n_args] = NULL;
+
+ return arg_types;
+}
+
+/**
+ * g_callable_info_get_ffi_return_type:
+ * @callable_info: a callable info from a typelib
+ *
+ * Fetches the ffi_type for a corresponding return value of
+ * a #GICallableInfo
+ * Return value: the ffi_type for the return value
+ */
+ffi_type *
+g_callable_info_get_ffi_return_type (GICallableInfo *callable_info)
+{
+ GITypeInfo *return_type;
+ GITypeTag type_tag;
+
+ g_return_val_if_fail (callable_info != NULL, NULL);
+
+ return_type = g_callable_info_get_return_type (callable_info);
+ type_tag = g_type_info_get_tag (return_type);
+ return g_ir_ffi_get_ffi_type (type_tag);
+}
+
+/**
+ * g_callable_info_prepare_closure:
+ * @callable_info: a callable info from a typelib
+ * @cif: a ffi_cif structure
+ * @callback: the ffi callback
+ * @user_data: data to be passed into the callback
+ *
+ * Prepares a callback for ffi invocation.
+ *
+ * Note: this function requires the heap to be executable, which
+ * might not function properly on systems with SELinux enabled.
+ *
+ * Return value: the ffi_closure or NULL on error.
+ * The return value should be freed by calling g_callable_info_prepare_closure().
+ */
+ffi_closure *
+g_callable_info_prepare_closure (GICallableInfo *callable_info,
+ ffi_cif *cif,
+ GIFFIClosureCallback callback,
+ gpointer user_data)
+{
+ ffi_closure *closure;
+ ffi_status status;
+
+ g_return_val_if_fail (callable_info != NULL, FALSE);
+ g_return_val_if_fail (cif != NULL, FALSE);
+ g_return_val_if_fail (callback != NULL, FALSE);
+
+ closure = mmap (NULL, sizeof (ffi_closure),
+ PROT_EXEC | PROT_READ | PROT_WRITE,
+ MAP_ANON | MAP_PRIVATE, -1, sysconf (_SC_PAGE_SIZE));
+ if (!closure)
+ {
+ g_warning("mmap failed: %s\n", strerror(errno));
+ return NULL;
+ }
+
+ status = ffi_prep_cif (cif, FFI_DEFAULT_ABI,
+ g_callable_info_get_n_args (callable_info),
+ g_callable_info_get_ffi_return_type (callable_info),
+ g_callable_info_get_ffi_arg_types (callable_info));
+ if (status != FFI_OK)
+ {
+ g_warning("ffi_prep_cif failed: %d\n", status);
+ munmap(closure, sizeof (closure));
+ return NULL;
+ }
+
+ status = ffi_prep_closure (closure, cif, callback, user_data);
+ if (status != FFI_OK)
+ {
+ g_warning ("ffi_prep_closure failed: %d\n", status);
+ munmap(closure, sizeof (closure));
+ return NULL;
+ }
+
+ if (mprotect(closure, sizeof (closure), PROT_READ | PROT_EXEC) == -1)
+ {
+ g_warning ("ffi_prep_closure failed: %s\n", strerror(errno));
+ munmap(closure, sizeof (closure));
+ return NULL;
+ }
+
+ return closure;
+}
+
+/**
+ * g_callable_info_prepare_closure:
+ * @callable_info: a callable info from a typelib
+ * @closure: ffi closure
+ *
+ * Frees a ffi_closure returned from g_callable_info_prepare_closure()
+ */
+void
+g_callable_info_free_closure (GICallableInfo *callable_info,
+ ffi_closure *closure)
+{
+ munmap(closure, sizeof (closure));
+}
projects / gnome.gobject-introspection / commitdiff