sysctl-rs makes extensive use of sysctl oidfmt to look up the type and format of sysctls. Unfortunately, this is not allowed on non-jailbroken iOS as any such calls return -EPERM. Instead, we should be using sysctlbyname on iOS, which means that we are way more restricted since we cannot look up the type or format, and as such the user will have to provide these for full iOS support. In addition, the original implementation does work on jailbroken iOS, so we want to keep that option available (e.g. you could first try using Ctl::new() and then fallback to Ctl::new_with_type() to support both).
This PR changes the following things:
Ctl in unix.rs is now an enum that either contains the oid or the name + type + format string.
Ctl in unix.rs implements oid() to return a reference to the oid, in case the underlying Oid variant is used. This is a breaking change (requires a version bump to 0.5.0), as Ctl used to contain a pub oid that now no longer exists.
The Sysctl trait is extended with a new_with_type() function to construct a Ctl from a name, type and format string. On other platforms (i.e. not MacOS or iOS), this function will simply ignore the type and format string and instead fallback to the original oid implementation as that works fine.
To get/set the value for the named Ctl variant, there are now functions that use sysctlbyname + the supplied type and format string instead of sysctl + oidfmtinternally.
CtlIter still uses oids, but that is fine. As on iOS this should just fail gracefully. That does mean that you cannot iterate over the available sysctls on a non-jailbroken iOS.
johalun
commented
2 years ago
sysctl-rs makes extensive use of sysctl oidfmt to look up the type and format of sysctls. Unfortunately, this is not allowed on non-jailbroken iOS as any such calls return
-EPERM. Instead, we should be usingsysctlbynameon iOS, which means that we are way more restricted since we cannot look up the type or format, and as such the user will have to provide these for full iOS support. In addition, the original implementation does work on jailbroken iOS, so we want to keep that option available (e.g. you could first try usingCtl::new()and then fallback toCtl::new_with_type()to support both).This PR changes the following things:
Ctlinunix.rsis now an enum that either contains the oid or the name + type + format string.Ctlinunix.rsimplementsoid()to return a reference to the oid, in case the underlying Oid variant is used. This is a breaking change (requires a version bump to 0.5.0), asCtlused to contain apub oidthat now no longer exists.Sysctltrait is extended with anew_with_type()function to construct aCtlfrom a name, type and format string. On other platforms (i.e. not MacOS or iOS), this function will simply ignore the type and format string and instead fallback to the original oid implementation as that works fine.Ctlvariant, there are now functions that usesysctlbyname+ the supplied type and format string instead ofsysctl+oidfmtinternally.CtlIterstill uses oids, but that is fine. As on iOS this should just fail gracefully. That does mean that you cannot iterate over the available sysctls on a non-jailbroken iOS.