freebsd-dev/sys/kern/kern_environment.c
Archie Cobbs 25792ef324 Change the prototype of the strto* routines to make the second
parameter a char ** instead of a const char **.  This make these
kernel routines consistent with the corresponding libc userland
routines.

Which is actually 'correct' is debatable, but consistency and
following the spec was deemed more important in this case.

Reviewed by (in concept):	phk, bde
1999-11-24 01:03:08 +00:00

154 lines
3.6 KiB
C

/*-
* Copyright (c) 1998 Michael Smith
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*
* The unified bootloader passes us a pointer to a preserved copy of
* bootstrap/kernel environment variables.
* We make these available using sysctl for both in-kernel and
* out-of-kernel consumers.
*
* Note that the current sysctl infrastructure doesn't allow
* dynamic insertion or traversal through handled spaces. Grr.
*/
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/libkern.h>
char *kern_envp;
static char *kernenv_next(char *cp);
char *
getenv(char *name)
{
char *cp, *ep;
int len;
for (cp = kern_envp; cp != NULL; cp = kernenv_next(cp)) {
for (ep = cp; (*ep != '=') && (*ep != 0); ep++)
;
len = ep - cp;
if (*ep == '=')
ep++;
if (!strncmp(name, cp, len))
return(ep);
}
return(NULL);
}
/*
* Return an integer value from an environment variable.
*/
int
getenv_int(char *name, int *data)
{
quad_t tmp;
int rval;
rval = getenv_quad(name, &tmp);
if (rval) {
*data = (int) tmp;
}
return (rval);
}
/*
* Return a quad_t value from an environment variable.
*/
quad_t
getenv_quad(char *name, quad_t *data)
{
const char *value;
char *vtp;
quad_t iv;
if ((value = getenv(name)) == NULL)
return(0);
iv = strtoq(value, &vtp, 0);
if ((vtp == value) || (*vtp != '\0'))
return(0);
*data = iv;
return(1);
}
static int
sysctl_kernenv SYSCTL_HANDLER_ARGS
{
int *name = (int *)arg1;
u_int namelen = arg2;
char *cp;
int i, error;
if (kern_envp == NULL)
return(ENOENT);
name++;
namelen--;
if (namelen != 1)
return(EINVAL);
cp = kern_envp;
for (i = 0; i < name[0]; i++) {
cp = kernenv_next(cp);
if (cp == NULL)
break;
}
if (cp == NULL)
return(ENOENT);
error = SYSCTL_OUT(req, cp, strlen(cp) + 1);
return (error);
}
SYSCTL_NODE(_kern, OID_AUTO, environment, CTLFLAG_RD, sysctl_kernenv, "kernel environment space");
/*
* Find the next entry after the one which (cp) falls within, return a
* pointer to its start or NULL if there are no more.
*/
static char *
kernenv_next(char *cp)
{
if (cp != NULL) {
while (*cp != 0)
cp++;
cp++;
if (*cp == 0)
cp = NULL;
}
return(cp);
}