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-rw-r--r--src/libsystemd/sd-bus/bus-error.h57
1 files changed, 57 insertions, 0 deletions
diff --git a/src/libsystemd/sd-bus/bus-error.h b/src/libsystemd/sd-bus/bus-error.h
new file mode 100644
index 0000000..c8768c9
--- /dev/null
+++ b/src/libsystemd/sd-bus/bus-error.h
@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#include <stdbool.h>
+
+#include "sd-bus.h"
+
+#include "errno-util.h"
+#include "macro.h"
+
+bool bus_error_is_dirty(sd_bus_error *e);
+
+const char* _bus_error_message(const sd_bus_error *e, int error, char buf[static ERRNO_BUF_LEN]);
+
+/* Note: the lifetime of the compound literal is the immediately surrounding block,
+ * see C11 ยง6.5.2.5, and
+ * https://stackoverflow.com/questions/34880638/compound-literal-lifetime-and-if-blocks */
+#define bus_error_message(e, error) _bus_error_message(e, error, (char[ERRNO_BUF_LEN]){})
+
+#define BUS_ERROR_OOM SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_NO_MEMORY, "Out of memory")
+#define BUS_ERROR_FAILED SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_FAILED, "Operation failed")
+
+/*
+ * There are two ways to register error maps with the error translation
+ * logic: by using BUS_ERROR_MAP_ELF_REGISTER, which however only
+ * works when linked into the same ELF module, or via
+ * sd_bus_error_add_map() which is the official, external API, that
+ * works from any module.
+ *
+ * Note that BUS_ERROR_MAP_ELF_REGISTER has to be used as decorator in
+ * the bus error table, and BUS_ERROR_MAP_ELF_USE has to be used at
+ * least once per compilation unit (i.e. per library), to ensure that
+ * the error map is really added to the final binary.
+ *
+ * In addition, set the retain attribute so that the section cannot be
+ * discarded by ld --gc-sections -z start-stop-gc. Older compilers would
+ * warn for the unknown attribute, so just disable -Wattributes.
+ */
+
+#define BUS_ERROR_MAP_ELF_REGISTER \
+ _Pragma("GCC diagnostic ignored \"-Wattributes\"") \
+ _section_("SYSTEMD_BUS_ERROR_MAP") \
+ _used_ \
+ _retain_ \
+ _alignptr_ \
+ _variable_no_sanitize_address_
+
+#define BUS_ERROR_MAP_ELF_USE(errors) \
+ extern const sd_bus_error_map errors[]; \
+ _used_ \
+ static const sd_bus_error_map * const CONCATENATE(errors ## _copy_, __COUNTER__) = errors;
+
+/* We use something exotic as end marker, to ensure people build the
+ * maps using the macsd-ros. */
+#define BUS_ERROR_MAP_END_MARKER -'x'
+
+BUS_ERROR_MAP_ELF_USE(bus_standard_errors);