sd-bus: add new API call sd_bus_error_move()

This new call move an sd_bus_error into another one.

(cherry picked from commit 190128e407eb24a445554c0e1f956a1d51f97338)

In the backport, the new function is made non-public, declared in bus-error.h
not sd-bus.h.

2 files changed, 24 insertions, 0 deletions

diff --git a/src/libelogind/sd-bus/bus-error.c b/src/libelogind/sd-bus/bus-error.c
index ec359ac13..f0673225c 100644
--- a/src/libelogind/sd-bus/bus-error.c
+++ b/src/libelogind/sd-bus/bus-error.c
@@ -310,6 +310,28 @@ finish:
         return -bus_error_name_to_errno(e->name);
 }
 
+int sd_bus_error_move(sd_bus_error *dest, sd_bus_error *e) {
+        int r;
+
+        if (!sd_bus_error_is_set(e)) {
+
+                if (dest)
+                        *dest = SD_BUS_ERROR_NULL;
+
+                return 0;
+        }
+
+        r = -bus_error_name_to_errno(e->name);
+
+        if (dest) {
+                *dest = *e;
+                *e = SD_BUS_ERROR_NULL;
+        } else
+                sd_bus_error_free(e);
+
+        return r;
+}
+
 _public_ int sd_bus_error_set_const(sd_bus_error *e, const char *name, const char *message) {
         if (!name)
                 return 0;
diff --git a/src/libelogind/sd-bus/bus-error.h b/src/libelogind/sd-bus/bus-error.h
index 93cb9acd9..45146fe81 100644
--- a/src/libelogind/sd-bus/bus-error.h
+++ b/src/libelogind/sd-bus/bus-error.h
@@ -47,3 +47,5 @@ int bus_error_set_errnofv(sd_bus_error *e, int error, const char *format, va_lis
 #define BUS_ERROR_MAP_END_MARKER -'x'
 
 BUS_ERROR_MAP_ELF_USE(bus_standard_errors);
+
+int sd_bus_error_move(sd_bus_error *dest, sd_bus_error *e);