sd_bus_error_add_map
systemd
Developer
Lennart
Poettering
lennart@poettering.net
sd_bus_error_add_map
3
sd_bus_error_add_map
sd_bus_error_map
SD_BUS_ERROR_MAP
SD_BUS_ERROR_END
Additional sd-dbus error mappings
#include <systemd/sd-bus.h>
typedef struct {
const char *name;
int code;
...
} sd_bus_error_map;
SD_BUS_ERROR_MAP(name, code)
SD_BUS_ERROR_MAP_END
int sd_bus_error_add_map
const sd_bus_map *map
Description
The sd_bus_error_add_map() call may be
used to register additional mappings for converting D-Bus errors
to Linux errno-style errors. The mappings
defined with this call are consulted by calls such as
sd_bus_error_set3
or
sd_bus_error_get_errno3. By
default, a number of generic, standardized mappings are known, as
documented in
sd-bus-errors3. Use
this call to add further, application-specific mappings.
The function takes a pointer to an array of
sd_bus_error_map structures. A reference
to the specified array is added to the lookup tables for error
mappings. Note that the structure is not copied, and that it is hence
essential that the array stays available and constant during the
entire remaining runtime of the process.
The mapping array should be put together with a series of
SD_BUS_ERROR_MAP() macro invocations that
take a literal name string and a (positive)
errno-style error number. The last entry of the
array should be an invocation of the
SD_BUS_ERROR_MAP_END macro. The array should not be
put together without use of these two macros.
Note that the call is idempotent: it is safe to invoke it
multiple times with the parameter, which will only add the passed
mapping array once.
Note that the memory allocated by this call is not intended
to be freed during the lifetime of the process. It should not be
freed explicitly.
Return Value
sd_bus_error_add_map() returns a
positive value when the new array was added to the lookup
tables. It returns zero when the same array was already added
before. On error, a negative errno-style error
code is returned. See below for known error codes.
Errors
Returned errors may indicate the following problems:
-EINVAL
The specified mapping array is invalid.
-ENOMEM
Memory allocation failed.
Notes
The various error definitions described here are available
as a shared library, which can be compiled and linked to with the
libsystemd pkg-config1
file.
See Also
systemd1,
sd-bus3,
sd_bus_error3,
sd-bus-errors3,
errno3,
strerror_r3