lightning/common/errcode.h

#ifndef LIGHTNING_COMMON_ERRCODE_H
#define LIGHTNING_COMMON_ERRCODE_H

#include "config.h"

#include <ccan/short_types/short_types.h>
#include <inttypes.h>

typedef s32 errcode_t;

#define PRIerrcode PRId32

#endif /* LIGHTNING_COMMON_ERRCODE_H */
Use dedicated type for error codes 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 5 years ago			`#ifndef LIGHTNING_COMMON_ERRCODE_H`
			`#define LIGHTNING_COMMON_ERRCODE_H`

			`#include "config.h"`

			`#include <ccan/short_types/short_types.h>`
			`#include <inttypes.h>`

			`typedef s32 errcode_t;`

			`#define PRIerrcode PRId32`

			`#endif /* LIGHTNING_COMMON_ERRCODE_H */`