[glib2] Fix signal marshalling on 64-bit big-endian platforms (rh #736489)
Daniel Williams
dcbw at fedoraproject.org
Wed Oct 5 20:11:43 UTC 2011
commit ca35b29fac74d4384e3fd49005dc0cd677fd4394
Author: Dan Williams <dcbw at redhat.com>
Date: Wed Oct 5 15:11:33 2011 -0500
Fix signal marshalling on 64-bit big-endian platforms (rh #736489)
...-handling-of-ENUMs-and-integral-return-ty.patch | 218 ++++++++++++++++++++
glib2.spec | 6 +
2 files changed, 224 insertions(+), 0 deletions(-)
---
diff --git a/0001-closure-fix-handling-of-ENUMs-and-integral-return-ty.patch b/0001-closure-fix-handling-of-ENUMs-and-integral-return-ty.patch
new file mode 100644
index 0000000..06a39b7
--- /dev/null
+++ b/0001-closure-fix-handling-of-ENUMs-and-integral-return-ty.patch
@@ -0,0 +1,218 @@
+From 8e82225aedf81ea8a33deb3eb27a8878cd606521 Mon Sep 17 00:00:00 2001
+From: Dan Williams <dcbw at redhat.com>
+Date: Fri, 23 Sep 2011 12:32:23 -0500
+Subject: [PATCH] closure: fix handling of ENUMs and integral return types on
+ 64-bit BE platforms
+
+enums are stored in v_long but need to be marshalled as signed
+integers. On platforms where int is 32 bits, taking the
+address of v_long resulted in the wrong 32 bits being marshalled.
+So we need to stuff the enum's int-sized value to a temporary
+int-sized variable and marshall that instead.
+
+Second, on return, libffi actually returns a pointer to a value
+that's sized according to platform conventions, not according to
+what the caller requested. ie if ffi_type_sint was requested, the
+value can still be a 64-bit sign-extended long on a 64-bit
+architecture like PPC64, thus the caller cannot simply cast
+the return value as a pointer to the desired type, but must cast
+as a pointer to an integral type and then cast to the desired
+type to remove any sign extension complications.
+
+For more information on how to correctly handle libffi return
+values, see the following bug, specifically comment 35:
+
+https://bugzilla.redhat.com/show_bug.cgi?id=736489
+
+"For 64-bit ABIs that extend integral returns types to 64-bits, libffi always
+returns full 64-bit values that you can truncate in the calling code. It's
+just the way it is has always been. Please don't change libffi. I'll document
+this clearly for the next version (perhaps there is a mention of this, I
+haven't looked yet).
+
+The same is true for returning 8-bit values, for instance, on 32-bit systems.
+All ABIs extend those results to the full 32-bits so you need to provide a
+properly aligned buffer that's big enough to hold the result."
+
+https://bugzilla.gnome.org/show_bug.cgi?id=659881
+---
+ gobject/gclosure.c | 76 ++++++++++++++++++++++++++++++++++++++++-----------
+ 1 files changed, 59 insertions(+), 17 deletions(-)
+
+diff --git a/gobject/gclosure.c b/gobject/gclosure.c
+index 36ec4b0..6893484 100644
+--- a/gobject/gclosure.c
++++ b/gobject/gclosure.c
+@@ -944,21 +944,42 @@ g_signal_type_cclosure_new (GType itype,
+
+ #include <ffi.h>
+ static ffi_type *
+-value_to_ffi_type (const GValue *gvalue, gpointer *value)
++value_to_ffi_type (const GValue *gvalue,
++ gpointer *value,
++ gint *enum_tmpval,
++ gboolean *tmpval_used)
+ {
+ ffi_type *rettype = NULL;
+ GType type = g_type_fundamental (G_VALUE_TYPE (gvalue));
+ g_assert (type != G_TYPE_INVALID);
+
++ if (enum_tmpval)
++ {
++ g_assert (tmpval_used != NULL);
++ *tmpval_used = FALSE;
++ }
++
+ switch (type)
+ {
+ case G_TYPE_BOOLEAN:
+ case G_TYPE_CHAR:
+ case G_TYPE_INT:
+- case G_TYPE_ENUM:
+ rettype = &ffi_type_sint;
+ *value = (gpointer)&(gvalue->data[0].v_int);
+ break;
++ case G_TYPE_ENUM:
++ /* enums are stored in v_long even though they are integers, which makes
++ * marshalling through libffi somewhat complicated. They need to be
++ * marshalled as signed ints, but we need to use a temporary int sized
++ * value to pass to libffi otherwise it'll pull the wrong value on
++ * BE machines with 32-bit integers when treating v_long as 32-bit int.
++ */
++ g_assert (enum_tmpval != NULL);
++ rettype = &ffi_type_sint;
++ *enum_tmpval = g_value_get_enum (gvalue);
++ *value = enum_tmpval;
++ *tmpval_used = TRUE;
++ break;
+ case G_TYPE_UCHAR:
+ case G_TYPE_UINT:
+ case G_TYPE_FLAGS:
+@@ -1011,10 +1032,12 @@ value_to_ffi_type (const GValue *gvalue, gpointer *value)
+ static void
+ value_from_ffi_type (GValue *gvalue, gpointer *value)
+ {
++ ffi_arg *int_val = value;
++
+ switch (g_type_fundamental (G_VALUE_TYPE (gvalue)))
+ {
+ case G_TYPE_INT:
+- g_value_set_int (gvalue, *(gint*)value);
++ g_value_set_int (gvalue, (gint) *int_val);
+ break;
+ case G_TYPE_FLOAT:
+ g_value_set_float (gvalue, *(gfloat*)value);
+@@ -1023,43 +1046,43 @@ value_from_ffi_type (GValue *gvalue, gpointer *value)
+ g_value_set_double (gvalue, *(gdouble*)value);
+ break;
+ case G_TYPE_BOOLEAN:
+- g_value_set_boolean (gvalue, *(gboolean*)value);
++ g_value_set_boolean (gvalue, (gboolean) *int_val);
+ break;
+ case G_TYPE_STRING:
+ g_value_set_string (gvalue, *(gchar**)value);
+ break;
+ case G_TYPE_CHAR:
+- g_value_set_char (gvalue, *(gchar*)value);
++ g_value_set_char (gvalue, (gchar) *int_val);
+ break;
+ case G_TYPE_UCHAR:
+- g_value_set_uchar (gvalue, *(guchar*)value);
++ g_value_set_uchar (gvalue, (guchar) *int_val);
+ break;
+ case G_TYPE_UINT:
+- g_value_set_uint (gvalue, *(guint*)value);
++ g_value_set_uint (gvalue, (guint) *int_val);
+ break;
+ case G_TYPE_POINTER:
+ g_value_set_pointer (gvalue, *(gpointer*)value);
+ break;
+ case G_TYPE_LONG:
+- g_value_set_long (gvalue, *(glong*)value);
++ g_value_set_long (gvalue, (glong) *int_val);
+ break;
+ case G_TYPE_ULONG:
+- g_value_set_ulong (gvalue, *(gulong*)value);
++ g_value_set_ulong (gvalue, (gulong) *int_val);
+ break;
+ case G_TYPE_INT64:
+- g_value_set_int64 (gvalue, *(gint64*)value);
++ g_value_set_int64 (gvalue, (gint64) *int_val);
+ break;
+ case G_TYPE_UINT64:
+- g_value_set_uint64 (gvalue, *(guint64*)value);
++ g_value_set_uint64 (gvalue, (guint64) *int_val);
+ break;
+ case G_TYPE_BOXED:
+ g_value_set_boxed (gvalue, *(gpointer*)value);
+ break;
+ case G_TYPE_ENUM:
+- g_value_set_enum (gvalue, *(gint*)value);
++ g_value_set_enum (gvalue, (gint) *int_val);
+ break;
+ case G_TYPE_FLAGS:
+- g_value_set_flags (gvalue, *(guint*)value);
++ g_value_set_flags (gvalue, (guint) *int_val);
+ break;
+ case G_TYPE_PARAM:
+ g_value_set_param (gvalue, *(gpointer*)value);
+@@ -1108,10 +1131,13 @@ g_cclosure_marshal_generic (GClosure *closure,
+ int i;
+ ffi_cif cif;
+ GCClosure *cc = (GCClosure*) closure;
++ gint *enum_tmpval;
++ gboolean tmpval_used = FALSE;
+
++ enum_tmpval = g_alloca (sizeof (gint));
+ if (return_gvalue && G_VALUE_TYPE (return_gvalue))
+ {
+- rtype = value_to_ffi_type (return_gvalue, &rvalue);
++ rtype = value_to_ffi_type (return_gvalue, &rvalue, enum_tmpval, &tmpval_used);
+ }
+ else
+ {
+@@ -1124,22 +1150,38 @@ g_cclosure_marshal_generic (GClosure *closure,
+ atypes = g_alloca (sizeof (ffi_type *) * n_args);
+ args = g_alloca (sizeof (gpointer) * n_args);
+
++ if (tmpval_used)
++ enum_tmpval = g_alloca (sizeof (gint));
++
+ if (G_CCLOSURE_SWAP_DATA (closure))
+ {
+ atypes[n_args-1] = value_to_ffi_type (param_values + 0,
+- &args[n_args-1]);
++ &args[n_args-1],
++ enum_tmpval,
++ &tmpval_used);
+ atypes[0] = &ffi_type_pointer;
+ args[0] = &closure->data;
+ }
+ else
+ {
+- atypes[0] = value_to_ffi_type (param_values + 0, &args[0]);
++ atypes[0] = value_to_ffi_type (param_values + 0,
++ &args[0],
++ enum_tmpval,
++ &tmpval_used);
+ atypes[n_args-1] = &ffi_type_pointer;
+ args[n_args-1] = &closure->data;
+ }
+
+ for (i = 1; i < n_args - 1; i++)
+- atypes[i] = value_to_ffi_type (param_values + i, &args[i]);
++ {
++ if (tmpval_used)
++ enum_tmpval = g_alloca (sizeof (gint));
++
++ atypes[i] = value_to_ffi_type (param_values + i,
++ &args[i],
++ enum_tmpval,
++ &tmpval_used);
++ }
+
+ if (ffi_prep_cif (&cif, FFI_DEFAULT_ABI, n_args, rtype, atypes) != FFI_OK)
+ return;
+--
+1.7.6.4
+
diff --git a/glib2.spec b/glib2.spec
index 36f3575..a1816b5 100644
--- a/glib2.spec
+++ b/glib2.spec
@@ -10,6 +10,8 @@ URL: http://www.gtk.org
#VCS: git:git://git.gnome.org/glib
Source: http://download.gnome.org/sources/glib/2.29/glib-%{version}.tar.xz
+Patch0: 0001-closure-fix-handling-of-ENUMs-and-integral-return-ty.patch
+
BuildRequires: pkgconfig
BuildRequires: gamin-devel
BuildRequires: gettext
@@ -57,6 +59,7 @@ The glib2-static package includes static libraries of the GLib library.
%prep
%setup -q -n glib-%{version}
+%patch0 -p1 -b .ffi
%build
# Support builds of both git snapshots and tarballs packed with autogoo
@@ -159,6 +162,9 @@ gio-querymodules-%{__isa_bits} %{_libdir}/gio/modules
%changelog
+* Wed Oct 05 2011 Dan Williams <dcbw at redhat.com> - 2.30.0-2
+- Fix signal marshalling on 64-bit big-endian platforms (rh #736489)
+
* Mon Sep 26 2011 Ray <rstrode at redhat.com> - 2.30.0-1
- Update to 2.30.0
More information about the scm-commits
mailing list