Before this patch we used `int` for error codes. The problem with
`int` is that we try to pass it to/from wire and the size of `int` is
not defined by the standard. So a sender with 4-byte `int` would write
4 bytes to the wire and a receiver with 2-byte `int` (for example) would
read just 2 bytes from the wire.
To resolve this:
* Introduce an error code type with a known size:
`typedef s32 errcode_t`.
* Change all error code macros to constants of type `errcode_t`.
Constants also play better with gdb - it would visualize the name of
the constant instead of the numeric value.
* Change all functions that take error codes to take the new type
`errcode_t` instead of `int`.
* Introduce towire / fromwire functions to send / receive the newly added
type `errcode_t` and use it instead of `towire_int()`.
In addition:
* Remove the now unneeded `towire_int()`.
* Replace a hardcoded error code `-2` with a new constant
`INVOICE_EXPIRED_DURING_WAIT` (903).
Changelog-Changed: The waitinvoice command would now return error code 903 to designate that the invoice expired during wait, instead of the previous -2
This causes a compiler warning if we don't do something with the
result (hopefully return immediately!).
We use was_pending() to ignore the result in the case where we
complete a command in a callback (thus really do want to ignore
the result).
This actually fixes one bug: we didn't return after command_fail
in json_getroute with a bad seed value.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
These routines free the 'struct command': a common coding error is not
to return immediately.
To catch this, we make them return a non-NULL 'struct command_result
*', and we're going to make the command handlers return the same (to
encourage 'return command_fail(...)'-style usage).
We also provide two sources for external use:
1. command_param_failed() when param() fails.
2. command_its_complicated() for some complex cases.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
I want to use param functions in plugins, and they don't have struct
command.
I had to use a special arg to param() for check to flag it as allowing
extra parameters, rather than adding a one-use accessor.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rusty Russell
Vasil Dimov