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#include <sys/cdefs.h>
#include <lib.h>
#include "namespace.h"
#include "extern.h"
#include <string.h>
/*
* The sysctl(2) system call, handled by the MIB service.
*/
int
__sysctl(const int * name, unsigned int namelen, void * oldp, size_t * oldlenp,
const void * newp, size_t newlen)
{
message m;
int r;
memset(&m, 0, sizeof(m));
m.m_lc_mib_sysctl.oldp = (vir_bytes)oldp;
m.m_lc_mib_sysctl.oldlen = (oldlenp != NULL) ? *oldlenp : 0;
m.m_lc_mib_sysctl.newp = (vir_bytes)newp;
m.m_lc_mib_sysctl.newlen = newlen;
m.m_lc_mib_sysctl.namelen = namelen;
m.m_lc_mib_sysctl.namep = (vir_bytes)name;
if (namelen <= CTL_SHORTNAME)
memcpy(m.m_lc_mib_sysctl.name, name, sizeof(*name) * namelen);
r = _syscall(MIB_PROC_NR, MIB_SYSCTL, &m);
/*
* We copy the NetBSD behavior of replying with the old length also if
* the call failed, typically with ENOMEM. This is undocumented
* behavior, but unfortunately relied on by sysctl(8) and other NetBSD
* userland code. If the call failed at the IPC level, the resulting
* value will be garbage, but it should then not be used anyway.
*/
if (oldlenp != NULL)
*oldlenp = m.m_mib_lc_sysctl.oldlen;
return r;
}
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