From e7927faf1792ad4c3c8a5b599240a7ee94b1a0cc Mon Sep 17 00:00:00 2001 From: Ryan Lortie Date: Thu, 27 May 2010 11:32:34 -0400 Subject: [PATCH] GVariant: One more FreeBSD fix FreeBSD's malloc() sometimes returns unaligned memory if you are requesting small sizes. This can get GVariant into trouble. For example, consider the type "mmi" containing the value "just nothing". According to the type signature, the memory containing this should be aligned to a boundary of 4 since it might contain an int. The serialised size of this value is 1 byte, however, and when you ask FreeBSD to allocate memory of that size, it knows you can't put an int into it so it doesn't bother aligning it. This patch modifies the GVariant serialiser to not assert the alignment constraint in the case that the size of the serialised data is smaller than its own alignment requirement. --- glib/gvariant-serialiser.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/glib/gvariant-serialiser.c b/glib/gvariant-serialiser.c index a94a485e5..be5992748 100644 --- a/glib/gvariant-serialiser.c +++ b/glib/gvariant-serialiser.c @@ -129,7 +129,7 @@ static void g_variant_serialised_check (GVariantSerialised serialised) { gsize fixed_size; - guint alignment; + gsize alignment; g_assert (serialised.type_info != NULL); g_variant_type_info_query (serialised.type_info, &alignment, &fixed_size); @@ -157,6 +157,16 @@ g_variant_serialised_check (GVariantSerialised serialised) } ) - 9; + /* Some OSes (FreeBSD is a known example) have a malloc() that returns + * unaligned memory if you request small sizes. 'malloc (1);', for + * example, has been seen to return pointers aligned to 6 mod 16. + * + * Check if this is a small allocation and return without enforcing + * the alignment assertion if this is the case. + */ + if (serialised.size <= alignment) + return; + g_assert_cmpint (alignment & (gsize) serialised.data, ==, 0); } -- 2.34.1