freebsd-dev/sbin/geom/misc/subr.c
Pawel Jakub Dawidek 829781048d Move function for calculating number of bits into more central place.
I want to use it so more.

MFC after:	3 days
2005-08-19 22:13:09 +00:00

381 lines
7.6 KiB
C

/*-
* Copyright (c) 2004 Pawel Jakub Dawidek <pjd@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 AUTHORS 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 AUTHORS 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("$FreeBSD$");
#include <sys/param.h>
#include <sys/disk.h>
#include <sys/endian.h>
#include <sys/uio.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#include <assert.h>
#include <libgeom.h>
#include "misc/subr.h"
struct std_metadata {
char md_magic[16];
uint32_t md_version;
};
static void
std_metadata_decode(const u_char *data, struct std_metadata *md)
{
bcopy(data, md->md_magic, sizeof(md->md_magic));
md->md_version = le32dec(data + 16);
}
static void
pathgen(const char *name, char *path, size_t size)
{
if (strncmp(name, _PATH_DEV, strlen(_PATH_DEV)) != 0)
snprintf(path, size, "%s%s", _PATH_DEV, name);
else
strlcpy(path, name, size);
}
/*
* Greatest Common Divisor.
*/
static unsigned
gcd(unsigned a, unsigned b)
{
u_int c;
while (b != 0) {
c = a;
a = b;
b = (c % b);
}
return (a);
}
/*
* Least Common Multiple.
*/
unsigned
g_lcm(unsigned a, unsigned b)
{
return ((a * b) / gcd(a, b));
}
uint32_t
bitcount32(uint32_t x)
{
x = (x & 0x55555555) + ((x & 0xaaaaaaaa) >> 1);
x = (x & 0x33333333) + ((x & 0xcccccccc) >> 2);
x = (x & 0x0f0f0f0f) + ((x & 0xf0f0f0f0) >> 4);
x = (x & 0x00ff00ff) + ((x & 0xff00ff00) >> 8);
x = (x & 0x0000ffff) + ((x & 0xffff0000) >> 16);
return (x);
}
off_t
g_get_mediasize(const char *name)
{
char path[MAXPATHLEN];
off_t mediasize;
int fd;
pathgen(name, path, sizeof(path));
fd = open(path, O_RDONLY);
if (fd == -1)
return (0);
if (ioctl(fd, DIOCGMEDIASIZE, &mediasize) < 0) {
close(fd);
return (0);
}
close(fd);
return (mediasize);
}
unsigned
g_get_sectorsize(const char *name)
{
char path[MAXPATHLEN];
unsigned sectorsize;
int fd;
pathgen(name, path, sizeof(path));
fd = open(path, O_RDONLY);
if (fd == -1)
return (0);
if (ioctl(fd, DIOCGSECTORSIZE, &sectorsize) < 0) {
close(fd);
return (0);
}
close(fd);
return (sectorsize);
}
int
g_metadata_read(const char *name, u_char *md, size_t size, const char *magic)
{
struct std_metadata stdmd;
char path[MAXPATHLEN];
unsigned sectorsize;
off_t mediasize;
u_char *sector;
int error, fd;
pathgen(name, path, sizeof(path));
sector = NULL;
error = 0;
fd = open(path, O_RDONLY);
if (fd == -1)
return (errno);
mediasize = g_get_mediasize(name);
if (mediasize == 0) {
error = errno;
goto out;
}
sectorsize = g_get_sectorsize(name);
if (sectorsize == 0) {
error = errno;
goto out;
}
assert(sectorsize >= size);
sector = malloc(sectorsize);
if (sector == NULL) {
error = ENOMEM;
goto out;
}
if (pread(fd, sector, sectorsize, mediasize - sectorsize) !=
(ssize_t)sectorsize) {
error = errno;
goto out;
}
if (magic != NULL) {
std_metadata_decode(sector, &stdmd);
if (strcmp(stdmd.md_magic, magic) != 0) {
error = EINVAL;
goto out;
}
}
bcopy(sector, md, size);
out:
if (sector != NULL)
free(sector);
close(fd);
return (error);
}
int
g_metadata_store(const char *name, u_char *md, size_t size)
{
char path[MAXPATHLEN];
unsigned sectorsize;
off_t mediasize;
u_char *sector;
int error, fd;
pathgen(name, path, sizeof(path));
sector = NULL;
error = 0;
fd = open(path, O_WRONLY);
if (fd == -1)
return (errno);
mediasize = g_get_mediasize(name);
if (mediasize == 0) {
error = errno;
goto out;
}
sectorsize = g_get_sectorsize(name);
if (sectorsize == 0) {
error = errno;
goto out;
}
assert(sectorsize >= size);
sector = malloc(sectorsize);
if (sector == NULL) {
error = ENOMEM;
goto out;
}
bcopy(md, sector, size);
if (pwrite(fd, sector, sectorsize, mediasize - sectorsize) !=
(ssize_t)sectorsize) {
error = errno;
goto out;
}
out:
if (sector != NULL)
free(sector);
close(fd);
return (error);
}
int
g_metadata_clear(const char *name, const char *magic)
{
struct std_metadata md;
char path[MAXPATHLEN];
unsigned sectorsize;
off_t mediasize;
u_char *sector;
int error, fd;
pathgen(name, path, sizeof(path));
sector = NULL;
error = 0;
fd = open(path, O_RDWR);
if (fd == -1)
return (errno);
mediasize = g_get_mediasize(name);
if (mediasize == 0) {
error = errno;
goto out;
}
sectorsize = g_get_sectorsize(name);
if (sectorsize == 0) {
error = errno;
goto out;
}
sector = malloc(sectorsize);
if (sector == NULL) {
error = ENOMEM;
goto out;
}
if (magic != NULL) {
if (pread(fd, sector, sectorsize, mediasize - sectorsize) !=
(ssize_t)sectorsize) {
error = errno;
goto out;
}
std_metadata_decode(sector, &md);
if (strcmp(md.md_magic, magic) != 0) {
error = EINVAL;
goto out;
}
}
bzero(sector, sectorsize);
if (pwrite(fd, sector, sectorsize, mediasize - sectorsize) !=
(ssize_t)sectorsize) {
error = errno;
goto out;
}
out:
if (sector != NULL)
free(sector);
close(fd);
return (error);
}
/*
* Set an error message, if one does not already exist.
*/
void
gctl_error(struct gctl_req *req, const char *error, ...)
{
va_list ap;
if (req->error != NULL)
return;
va_start(ap, error);
vasprintf(&req->error, error, ap);
va_end(ap);
}
void *
gctl_get_param(struct gctl_req *req, const char *param, int *len)
{
unsigned i;
void *p;
struct gctl_req_arg *ap;
for (i = 0; i < req->narg; i++) {
ap = &req->arg[i];
if (strcmp(param, ap->name))
continue;
if (!(ap->flag & GCTL_PARAM_RD))
continue;
p = ap->value;
if (len != NULL)
*len = ap->len;
return (p);
}
return (NULL);
}
char const *
gctl_get_asciiparam(struct gctl_req *req, const char *param)
{
unsigned i;
char const *p;
struct gctl_req_arg *ap;
for (i = 0; i < req->narg; i++) {
ap = &req->arg[i];
if (strcmp(param, ap->name))
continue;
if (!(ap->flag & GCTL_PARAM_RD))
continue;
p = ap->value;
if (ap->len < 1) {
gctl_error(req, "No length argument (%s)", param);
return (NULL);
}
if (p[ap->len - 1] != '\0') {
gctl_error(req, "Unterminated argument (%s)", param);
return (NULL);
}
return (p);
}
return (NULL);
}
void *
gctl_get_paraml(struct gctl_req *req, const char *param, int len)
{
int i;
void *p;
p = gctl_get_param(req, param, &i);
if (p == NULL)
gctl_error(req, "Missing %s argument", param);
else if (i != len) {
p = NULL;
gctl_error(req, "Wrong length %s argument", param);
}
return (p);
}