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>

1 files changed, 25 insertions, 0 deletions

diff --git a/contrib/plugins/lockstep.c b/contrib/plugins/lockstep.c
index 6a7e9bbb39..62981d4e09 100644
--- a/contrib/plugins/lockstep.c
+++ b/contrib/plugins/lockstep.c
@@ -101,6 +101,31 @@ 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 };