Is their misbehavior part of the spec as well? If not, we can always add the correct behavior to the spec and let anyone who implemented a broken version deal with fixing every program compiled using it.
For strtoul and friends, maybe? 7.24.1 is pretty dense, but the key parts are "the expected form of the subject sequence is a sequence of letters and digits representing an integer with the radix specified by base, optionally preceded by a plus or minus sign […] If the correct value is outside the range of representable values […] ULONG_MAX […] is returned".
So the "expected form" allows a minus sign, but then it's clearly "outside the range of representable values" for strtoul to try parsing a negative value. So maybe it should return ULONG_MAX on those.
So arguably a minus sign present could already be treated as an error, and still be standard compliant. Unless I'm misreading.
Passing a negative value to a function that is specifically for converting strings into unsigned numbers is pretty much an error. In the case of functions that return an unsigned number, at least, negative return values can represent errors.
It’s more fun when the result can be signed though. Maybe strcmp with the representation of the LONG_MAX, and if it doesn’t match, call strtol and watch for a LONG_MAX indicating an error.
C is a bit messy. Would be nicer to return a struct with a possible error and the desired value, Golang style.
Is their misbehavior part of the spec as well? If not, we can always add the correct behavior to the spec and let anyone who implemented a broken version deal with fixing every program compiled using it.
Fair enough.
For strtoul and friends, maybe? 7.24.1 is pretty dense, but the key parts are "the expected form of the subject sequence is a sequence of letters and digits representing an integer with the radix specified by base, optionally preceded by a plus or minus sign […] If the correct value is outside the range of representable values […] ULONG_MAX […] is returned".
So the "expected form" allows a minus sign, but then it's clearly "outside the range of representable values" for strtoul to try parsing a negative value. So maybe it should return ULONG_MAX on those.
So arguably a minus sign present could already be treated as an error, and still be standard compliant. Unless I'm misreading.
Passing a negative value to a function that is specifically for converting strings into unsigned numbers is pretty much an error. In the case of functions that return an unsigned number, at least, negative return values can represent errors.
It’s more fun when the result can be signed though. Maybe strcmp with the representation of the LONG_MAX, and if it doesn’t match, call strtol and watch for a LONG_MAX indicating an error.
C is a bit messy. Would be nicer to return a struct with a possible error and the desired value, Golang style.