mq: add x32-specific implementations to work around mismatched kernel ABI

the kernel mq_attr structure has 8 64-bit longs instead of 8 32-bit
longs.

it's not clear that this is the nicest way to implement the fix, but
the concept (translation) is right, and the details can be changed
later if desired.

1 files changed, 14 insertions, 0 deletions

diff --git a/src/mq/x32/mq_setattr.c b/src/mq/x32/mq_setattr.c
new file mode 100644
index 00000000..0c631175
--- /dev/null
+++ b/src/mq/x32/mq_setattr.c
@@ -0,0 +1,14 @@
+#include <mqueue.h>
+#include "syscall.h"
+
+int mq_setattr(mqd_t mqd, const struct mq_attr *restrict new, struct mq_attr *restrict old)
+{
+	long long attr[8];
+	if (new) for (int i=0; i<8; i++)
+		attr[i] = *(long *)((char *)new + i*sizeof(long));
+	int ret = __syscall(SYS_mq_getsetattr, mqd, new?attr:0, old?attr:0);
+	if (ret < 0) return __syscall_ret(ret);
+	if (old) for (int i=0; i<8; i++)
+		*(long *)((char *)old + i*sizeof(long)) = attr[i];
+	return 0;
+}