FreeBSD-5.3/sys/kern/subr_hints.c
/*-
* Copyright (c) 2000,2001 Peter Wemm <peter@FreeBSD.org>
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/sys/kern/subr_hints.c,v 1.9 2003/07/02 16:01:38 jhb Exp $");
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/sx.h>
#include <sys/systm.h>
#include <sys/bus.h>
/*
* Access functions for device resources.
*/
static int checkmethod = 1;
static int use_kenv;
static char *hintp;
/*
* Evil wildcarding resource string lookup.
* This walks the supplied env string table and returns a match.
* The start point can be remembered for incremental searches.
*/
static int
res_find(int *line, int *startln,
const char *name, int *unit, const char *resname, const char *value,
const char **ret_name, int *ret_namelen, int *ret_unit,
const char **ret_resname, int *ret_resnamelen, const char **ret_value)
{
int n = 0, hit, i = 0;
char r_name[32];
int r_unit;
char r_resname[32];
char r_value[128];
const char *s, *cp;
char *p;
if (checkmethod) {
switch (hintmode) {
case 0: /* loader hints in environment only */
break;
case 1: /* static hints only */
hintp = static_hints;
checkmethod = 0;
break;
case 2: /* fallback mode */
if (dynamic_kenv) {
sx_slock(&kenv_lock);
cp = kenvp[0];
for (i = 0; cp != NULL; cp = kenvp[++i]) {
if (!strncmp(cp, "hint.", 5)) {
use_kenv = 1;
checkmethod = 0;
break;
}
}
sx_sunlock(&kenv_lock);
} else {
cp = kern_envp;
while (cp) {
if (strncmp(cp, "hint.", 5) == 0) {
cp = NULL;
hintp = kern_envp;
break;
}
while (*cp != '\0')
cp++;
cp++;
if (*cp == '\0') {
cp = NULL;
hintp = static_hints;
break;
}
}
}
break;
default:
break;
}
if (hintp == NULL) {
if (dynamic_kenv) {
use_kenv = 1;
checkmethod = 0;
} else
hintp = kern_envp;
}
}
if (use_kenv) {
sx_slock(&kenv_lock);
i = 0;
cp = kenvp[0];
if (cp == NULL) {
sx_sunlock(&kenv_lock);
return (ENOENT);
}
} else
cp = hintp;
while (cp) {
hit = 1;
(*line)++;
if (strncmp(cp, "hint.", 5) != 0)
hit = 0;
else
n = sscanf(cp, "hint.%32[^.].%d.%32[^=]=%128s",
r_name, &r_unit, r_resname, r_value);
if (hit && n != 4) {
printf("CONFIG: invalid hint '%s'\n", cp);
/* XXX: abuse bogus index() declaration */
p = index(cp, 'h');
*p = 'H';
hit = 0;
}
if (hit && startln && *startln >= 0 && *line < *startln)
hit = 0;
if (hit && name && strcmp(name, r_name) != 0)
hit = 0;
if (hit && unit && *unit != r_unit)
hit = 0;
if (hit && resname && strcmp(resname, r_resname) != 0)
hit = 0;
if (hit && value && strcmp(value, r_value) != 0)
hit = 0;
if (hit)
break;
if (use_kenv) {
cp = kenvp[++i];
if (cp == NULL)
break;
} else {
while (*cp != '\0')
cp++;
cp++;
if (*cp == '\0') {
cp = NULL;
break;
}
}
}
if (use_kenv)
sx_sunlock(&kenv_lock);
if (cp == NULL)
return ENOENT;
s = cp;
/* This is a bit of a hack, but at least is reentrant */
/* Note that it returns some !unterminated! strings. */
s = index(s, '.') + 1; /* start of device */
if (ret_name)
*ret_name = s;
s = index(s, '.') + 1; /* start of unit */
if (ret_namelen)
*ret_namelen = s - *ret_name - 1; /* device length */
if (ret_unit)
*ret_unit = r_unit;
s = index(s, '.') + 1; /* start of resname */
if (ret_resname)
*ret_resname = s;
s = index(s, '=') + 1; /* start of value */
if (ret_resnamelen)
*ret_resnamelen = s - *ret_resname - 1; /* value len */
if (ret_value)
*ret_value = s;
if (startln) /* line number for anchor */
*startln = *line + 1;
return 0;
}
/*
* Search all the data sources for matches to our query. We look for
* dynamic hints first as overrides for static or fallback hints.
*/
static int
resource_find(int *line, int *startln,
const char *name, int *unit, const char *resname, const char *value,
const char **ret_name, int *ret_namelen, int *ret_unit,
const char **ret_resname, int *ret_resnamelen, const char **ret_value)
{
int i;
int un;
*line = 0;
/* Search for exact unit matches first */
i = res_find(line, startln, name, unit, resname, value,
ret_name, ret_namelen, ret_unit, ret_resname, ret_resnamelen,
ret_value);
if (i == 0)
return 0;
if (unit == NULL)
return ENOENT;
/* If we are still here, search for wildcard matches */
un = -1;
i = res_find(line, startln, name, &un, resname, value,
ret_name, ret_namelen, ret_unit, ret_resname, ret_resnamelen,
ret_value);
if (i == 0)
return 0;
return ENOENT;
}
int
resource_int_value(const char *name, int unit, const char *resname, int *result)
{
int error;
const char *str;
char *op;
unsigned long val;
int line;
line = 0;
error = resource_find(&line, NULL, name, &unit, resname, NULL,
NULL, NULL, NULL, NULL, NULL, &str);
if (error)
return error;
if (*str == '\0')
return EFTYPE;
val = strtoul(str, &op, 0);
if (*op != '\0')
return EFTYPE;
*result = val;
return 0;
}
int
resource_long_value(const char *name, int unit, const char *resname,
long *result)
{
int error;
const char *str;
char *op;
unsigned long val;
int line;
line = 0;
error = resource_find(&line, NULL, name, &unit, resname, NULL,
NULL, NULL, NULL, NULL, NULL, &str);
if (error)
return error;
if (*str == '\0')
return EFTYPE;
val = strtoul(str, &op, 0);
if (*op != '\0')
return EFTYPE;
*result = val;
return 0;
}
int
resource_string_value(const char *name, int unit, const char *resname,
const char **result)
{
int error;
const char *str;
int line;
line = 0;
error = resource_find(&line, NULL, name, &unit, resname, NULL,
NULL, NULL, NULL, NULL, NULL, &str);
if (error)
return error;
*result = str;
return 0;
}
/*
* This is a bit nasty, but allows us to not modify the env strings.
*/
static const char *
resource_string_copy(const char *s, int len)
{
static char stringbuf[256];
static int offset = 0;
const char *ret;
if (len == 0)
len = strlen(s);
if (len > 255)
return NULL;
if ((offset + len + 1) > 255)
offset = 0;
bcopy(s, &stringbuf[offset], len);
stringbuf[offset + len] = '\0';
ret = &stringbuf[offset];
offset += len + 1;
return ret;
}
/*
* err = resource_find_at(&anchor, &name, &unit, resname, value)
* Iteratively fetch a list of devices wired "at" something
* res and value are restrictions. eg: "at", "scbus0".
* For practical purposes, res = required, value = optional.
* *name and *unit are set.
* set *anchor to zero before starting.
*/
int
resource_find_match(int *anchor, const char **name, int *unit,
const char *resname, const char *value)
{
const char *found_name;
int found_namelen;
int found_unit;
int ret;
int newln;
newln = *anchor;
ret = resource_find(anchor, &newln, NULL, NULL, resname, value,
&found_name, &found_namelen, &found_unit, NULL, NULL, NULL);
if (ret == 0) {
*name = resource_string_copy(found_name, found_namelen);
*unit = found_unit;
}
*anchor = newln;
return ret;
}
/*
* err = resource_find_dev(&anchor, name, &unit, res, value);
* Iterate through a list of devices, returning their unit numbers.
* res and value are optional restrictions. eg: "at", "scbus0".
* *unit is set to the value.
* set *anchor to zero before starting.
*/
int
resource_find_dev(int *anchor, const char *name, int *unit,
const char *resname, const char *value)
{
int found_unit;
int newln;
int ret;
newln = *anchor;
ret = resource_find(anchor, &newln, name, NULL, resname, value,
NULL, NULL, &found_unit, NULL, NULL, NULL);
if (ret == 0) {
*unit = found_unit;
}
*anchor = newln;
return ret;
}
/*
* Check to see if a device is disabled via a disabled hint.
*/
int
resource_disabled(const char *name, int unit)
{
int error, value;
error = resource_int_value(name, unit, "disabled", &value);
if (error)
return (0);
return (value);
}