NetBSD-5.0.2/share/examples/refuse/dmesgfs/dmesgfs.c
/*
* Copyright © 2007 Alistair Crooks. 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.
* 3. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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/types.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <fuse.h>
#include <regex.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "virtdir.h"
#include "defs.h"
static int verbose; /* how chatty are we? */
static virtdir_t pci;
/* a device node describes the device that is printed in the dmesg */
typedef struct devicenode_t {
char *dev; /* device name */
int devlen; /* length of name */
char *parent; /* its parent device name */
int parentlen; /* length of parent name */
char *descr; /* description of the device itself */
int descrlen; /* length of description */
int p; /* device node subscript of parent */
int dir; /* nonzero if this is a directory */
} devicenode_t;
DEFINE_ARRAY(devices_t, devicenode_t);
static devices_t devices;
/* perform the stat operation */
/* if this is the root, then just synthesise the data */
static int
dmesgfs_getattr(const char *path, struct stat *st)
{
virt_dirent_t *ep;
if (strcmp(path, "/") == 0) {
(void) memset(st, 0x0, sizeof(*st));
st->st_mode = (S_IFDIR | 0755);
st->st_nlink = 2;
return 0;
}
if ((ep = virtdir_find(&pci, path, strlen(path))) == NULL) {
return -ENOENT;
}
switch(ep->type) {
case 'f':
(void) memcpy(st, &pci.file, sizeof(*st));
st->st_size = ep->tgtlen;
st->st_mode = S_IFREG | 0644;
break;
case 'd':
(void) memcpy(st, &pci.dir, sizeof(*st));
break;
case 'l':
(void) memcpy(st, &pci.lnk, sizeof(*st));
st->st_size = ep->tgtlen;
st->st_mode = S_IFLNK | 0755;
break;
}
st->st_ino = virtdir_offset(&pci, ep) + 10;
return 0;
}
/* readdir operation */
static int
dmesgfs_readdir(const char *path, void *buf, fuse_fill_dir_t filler,
off_t offset, struct fuse_file_info * fi)
{
static VIRTDIR *dirp;
virt_dirent_t *dp;
if (offset == 0) {
if ((dirp = openvirtdir(&pci, path)) == NULL) {
return 0;
}
filler(buf, ".", NULL, 0);
filler(buf, "..", NULL, 0);
}
while ((dp = readvirtdir(dirp)) != NULL) {
if (filler(buf, dp->d_name, NULL, 0) != 0) {
return 0;
}
}
closevirtdir(dirp);
dirp = NULL;
return 0;
}
/* open the file in the file system */
static int
dmesgfs_open(const char *path, struct fuse_file_info * fi)
{
return 0;
}
/* read the file's contents in the file system */
static int
dmesgfs_read(const char *path, char *buf, size_t size, off_t offset,
struct fuse_file_info * fi)
{
virt_dirent_t *ep;
if ((ep = virtdir_find(&pci, path, strlen(path))) == NULL) {
return -ENOENT;
}
if (ep->tgt == NULL) {
return -ENOENT;
}
(void) memcpy(buf, &ep->tgt[offset], size);
return ep->tgtlen;
}
/* fill in the statvfs struct */
static int
dmesgfs_statfs(const char *path, struct statvfs *st)
{
(void) memset(st, 0x0, sizeof(*st));
return 0;
}
/* read the symbolic link */
static int
dmesgfs_readlink(const char *path, char *buf, size_t size)
{
virt_dirent_t *ep;
if ((ep = virtdir_find(&pci, path, strlen(path))) == NULL) {
return -ENOENT;
}
if (ep->tgt == NULL) {
return -ENOENT;
}
(void) strlcpy(buf, ep->tgt, size);
return 0;
}
/* operations struct */
static struct fuse_operations dmesgfs_oper = {
.getattr = dmesgfs_getattr,
.readlink = dmesgfs_readlink,
.readdir = dmesgfs_readdir,
.open = dmesgfs_open,
.read = dmesgfs_read,
.statfs = dmesgfs_statfs
};
/* save `n' chars of `s' in malloc'd memory */
static char *
strnsave(const char *s, int n)
{
char *cp;
if (n < 0) {
n = strlen(s);
}
NEWARRAY(char, cp, n + 1, "strnsave", exit(EXIT_FAILURE));
(void) memcpy(cp, s, n);
cp[n] = 0x0;
return cp;
}
/* find a device in the device node tree */
static int
finddev(const char *s, int len, int updir)
{
int i;
for (i = 0 ; i < devices.c ; i++) {
if (strncmp(devices.v[i].dev, s, len) == 0 &&
devices.v[i].devlen == len) {
if (updir) {
devices.v[i].dir = 1;
}
return i;
}
}
return -1;
}
/* add a device to the device node tree */
static void
add_dev(const char *dev, int len, const char *parent, int parentlen, const char *descr, int descrlen)
{
int d;
if ((d = finddev(dev, len, 0)) < 0) {
ALLOC(devicenode_t, devices.v, devices.size, devices.c, 10, 10, "add_dev", exit(EXIT_FAILURE));
devices.v[devices.c].dev = strnsave(dev, len);
devices.v[devices.c].devlen = len;
devices.v[devices.c].parent = strnsave(parent, parentlen);
devices.v[devices.c].parentlen = parentlen;
devices.v[devices.c].descr = strnsave(descr, descrlen);
devices.v[devices.c].descrlen = descrlen;
devices.c += 1;
}
}
/* print the parent device pathname */
static int
pparent(int d, char *buf, size_t size)
{
int cc;
if (d != 0) {
cc = pparent(devices.v[d].p, buf, size);
size -= cc;
}
(void) strlcat(buf, "/", size);
(void) strlcat(buf, devices.v[d].dev, size - 1);
return devices.v[d].devlen + 1;
}
#define NEXUS_DESCRIPTION "Nexus - the root of everything"
/* build up a fuse_tree from the information in the database */
static int
build_tree(virtdir_t *tp, const char *nexus, char type)
{
struct stat dir;
struct stat f;
regmatch_t matchv[10];
regex_t r;
FILE *pp;
char buf[BUFSIZ];
int i;
int p;
(void) stat(".", &dir);
(void) memcpy(&f, &dir, sizeof(f));
f.st_mode = S_IFREG | 0644;
if (regcomp(&r, "^([a-z0-9]+) at ([a-z0-9]+)(.*)", REG_EXTENDED) != 0) {
warn("can't compile regular expression\n");
return 0;
}
if ((pp = popen("dmesg", "r")) == NULL) {
return 0;
}
add_dev(nexus, strlen(nexus), nexus, strlen(nexus), NEXUS_DESCRIPTION,
strlen(NEXUS_DESCRIPTION));
while (fgets(buf, sizeof(buf), pp) != NULL) {
if (type == 'l') {
buf[strlen(buf) - 1] = 0x0;
}
if (regexec(&r, buf, 10, matchv, 0) == 0) {
add_dev(&buf[matchv[1].rm_so],
matchv[1].rm_eo - matchv[1].rm_so,
&buf[matchv[2].rm_so],
matchv[2].rm_eo - matchv[2].rm_so,
buf,
matchv[0].rm_eo - matchv[0].rm_so);
}
}
printf("%d devices\n", devices.c);
(void) pclose(pp);
for (i = 0 ; i < devices.c ; i++) {
if ((p = finddev(devices.v[i].parent, devices.v[i].parentlen, 1)) < 0) {
warn("No parent device for %s\n", devices.v[i].dev);
}
devices.v[i].p = p;
}
for (i = 0 ; i < devices.c ; i++) {
pparent(i, buf, sizeof(buf));
virtdir_add(tp, buf, strlen(buf),
(devices.v[i].dir) ? 'd' : type,
devices.v[i].descr, devices.v[i].descrlen);
if (devices.v[i].dir) {
(void) strlcat(buf, "/", sizeof(buf));
(void) strlcat(buf, "Description", sizeof(buf));
virtdir_add(tp, buf, strlen(buf), type,
devices.v[i].descr, devices.v[i].descrlen);
}
if (verbose) {
printf("dmesgfs: adding %s `%s' -> `%s'\n",
(type == 'l') ? "symbolic link" : "file",
buf, devices.v[i].descr);
}
buf[0] = 0x0;
}
return 1;
}
int
main(int argc, char **argv)
{
char *nexus;
char type;
int i;
nexus = NULL;
type = 'l';
while ((i = getopt(argc, argv, "fln:v")) != -1) {
switch(i) {
case 'f':
type = 'f';
break;
case 'l':
type = 'l';
break;
case 'n':
nexus = optarg;
break;
case 'v':
verbose += 1;
break;
}
}
if (!build_tree(&pci, (nexus) ? nexus : "mainbus0", type)) {
exit(EXIT_FAILURE);
}
return fuse_main(argc, argv, &dmesgfs_oper, NULL);
}