From 5b6fb9201164507134d8c14ed43bafd5d173f80e Mon Sep 17 00:00:00 2001 From: Johan Dahlin Date: Thu, 5 Feb 2009 00:40:14 +0000 Subject: [PATCH] Add utility functions for invocing closures given a GICallableInfo using 2009-02-04 Johan Dahlin * girepository/Makefile.am: * girepository/girffi.c (g_callable_info_get_ffi_arg_types), (g_callable_info_get_ffi_return_type), (g_callable_info_prepare_closure), (g_callable_info_free_closure): * girepository/girffi.h: Add utility functions for invocing closures given a GICallableInfo using libffi. svn path=/trunk/; revision=1084 --- ChangeLog | 10 +++ girepository/Makefile.am | 2 +- girepository/girffi.c | 139 +++++++++++++++++++++++++++++++++++++++ girepository/girffi.h | 15 ++++- 4 files changed, 164 insertions(+), 2 deletions(-) diff --git a/ChangeLog b/ChangeLog index 97d6b3b..eba9d78 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,13 @@ +2009-02-04 Johan Dahlin + + * girepository/Makefile.am: + * girepository/girffi.c (g_callable_info_get_ffi_arg_types), + (g_callable_info_get_ffi_return_type), + (g_callable_info_prepare_closure), (g_callable_info_free_closure): + * girepository/girffi.h: + Add utility functions for invocing closures given a GICallableInfo + using libffi. + 2009-02-03 Andreas Rottmann * tests/scanner/utility.h (UtilityTaggedValue): Make the union diff --git a/girepository/Makefile.am b/girepository/Makefile.am index dc8a6ca..1a449b2 100644 --- a/girepository/Makefile.am +++ b/girepository/Makefile.am @@ -3,7 +3,7 @@ include $(top_srcdir)/gcov.mak GCOVSOURCES = $(libgirepository_1_0_la_SOURCES) girepodir = $(includedir)/gobject-introspection-1.0/ -girepo_HEADERS = girepository.h +girepo_HEADERS = girepository.h girffi.h lib_LTLIBRARIES = libgirepository-1.0.la noinst_LTLIBRARIES = libgirepository-parser.la diff --git a/girepository/girffi.c b/girepository/girffi.c index d6eefb2..ffde853 100644 --- a/girepository/girffi.c +++ b/girepository/girffi.c @@ -19,7 +19,12 @@ * Boston, MA 02111-1307, USA. */ #include +#include +#include +#include +#include #include "girffi.h" +#include "girepository.h" ffi_type * g_ir_ffi_get_ffi_type (GITypeTag tag) @@ -98,3 +103,137 @@ 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)); +} diff --git a/girepository/girffi.h b/girepository/girffi.h index 842a233..a7d2876 100644 --- a/girepository/girffi.h +++ b/girepository/girffi.h @@ -26,7 +26,20 @@ G_BEGIN_DECLS -ffi_type *g_ir_ffi_get_ffi_type (GITypeTag tag); +typedef void (*GIFFIClosureCallback) (ffi_cif *, + void *, + void **, + void *); + +ffi_type * g_ir_ffi_get_ffi_type (GITypeTag tag); +ffi_type ** g_callable_info_get_ffi_arg_types (GICallableInfo *callable_info); +ffi_type * g_callable_info_get_ffi_return_type (GICallableInfo *callable_info); +ffi_closure * g_callable_info_prepare_closure (GICallableInfo *callable_info, + ffi_cif *cif, + GIFFIClosureCallback callback, + gpointer user_data); +void g_callable_info_free_closure (GICallableInfo *callable_info, + ffi_closure *closure); G_END_DECLS -- 2.39.2