contrib/plugins: add compat for g_memdup2

We were premature if bumping this because some of our builds are still
on older glibs. Just copy the compat handler for now and we can remove
it later.

Fixes: ee293103b0 (plugins: update lockstep to use g_memdup2)
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2161
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240729144414.830369-14-alex.bennee@linaro.org>
(cherry picked from commit 44e794896759236885f6d30d1f6b9b8b76355d52)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2681 in 8.2.x

diff --git a/contrib/plugins/lockstep.c b/contrib/plugins/lockstep.c
index 237543b43a76a1e657ddaef150314fc295366764..0c6f060183ac8cdb5d50db4488ea3cebd17ae9f7 100644 (file)
--- a/contrib/plugins/lockstep.c
+++ b/contrib/plugins/lockstep.c
@@ -100,6 +100,31 @@ static void plugin_exit(qemu_plugin_id_t id, void *p)
     plugin_cleanup(id);
 }
 
+/*
+ * g_memdup has been deprecated in Glib since 2.68 and
+ * will complain about it if you try to use it. However until
+ * glib_req_ver for QEMU is bumped we make a copy of the glib-compat
+ * handler.
+ */
+static inline gpointer g_memdup2_qemu(gconstpointer mem, gsize byte_size)
+{
+#if GLIB_CHECK_VERSION(2, 68, 0)
+    return g_memdup2(mem, byte_size);
+#else
+    gpointer new_mem;
+
+    if (mem && byte_size != 0) {
+        new_mem = g_malloc(byte_size);
+        memcpy(new_mem, mem, byte_size);
+    } else {
+        new_mem = NULL;
+    }
+
+    return new_mem;
+#endif
+}
+#define g_memdup2(m, s) g_memdup2_qemu(m, s)
+
 static void report_divergance(ExecState *us, ExecState *them)
 {
     DivergeState divrec = { log, 0 };