hush/procps/fuser.c
2008-07-05 09:18:54 +00:00

346 lines
7.1 KiB
C

/* vi: set sw=4 ts=4: */
/*
* tiny fuser implementation
*
* Copyright 2004 Tony J. White
*
* May be distributed under the conditions of the
* GNU Library General Public License
*/
#include "libbb.h"
#define MAX_LINE 255
#define OPTION_STRING "mks64"
enum {
OPT_MOUNT = (1 << 0),
OPT_KILL = (1 << 1),
OPT_SILENT = (1 << 2),
OPT_IP6 = (1 << 3),
OPT_IP4 = (1 << 4),
};
typedef struct inode_list {
struct inode_list *next;
ino_t inode;
dev_t dev;
} inode_list;
typedef struct pid_list {
struct pid_list *next;
pid_t pid;
} pid_list;
static dev_t find_socket_dev(void)
{
int fd = socket(AF_INET, SOCK_DGRAM, 0);
if (fd >= 0) {
struct stat buf;
int r = fstat(fd, &buf);
close(fd);
if (r == 0)
return buf.st_dev;
}
return 0;
}
static int file_to_dev_inode(const char *filename, dev_t *dev, ino_t *inode)
{
struct stat f_stat;
if (stat(filename, &f_stat))
return 0;
*inode = f_stat.st_ino;
*dev = f_stat.st_dev;
return 1;
}
static char *parse_net_arg(const char *arg, unsigned *port)
{
char path[20], tproto[5];
if (sscanf(arg, "%u/%4s", port, tproto) != 2)
return NULL;
sprintf(path, "/proc/net/%s", tproto);
if (access(path, R_OK) != 0)
return NULL;
return xstrdup(tproto);
}
static pid_list *add_pid(pid_list *plist, pid_t pid)
{
pid_list *curr = plist;
while (curr != NULL) {
if (curr->pid == pid)
return plist;
curr = curr->next;
}
curr = xmalloc(sizeof(pid_list));
curr->pid = pid;
curr->next = plist;
return curr;
}
static inode_list *add_inode(inode_list *ilist, dev_t dev, ino_t inode)
{
inode_list *curr = ilist;
while (curr != NULL) {
if (curr->inode == inode && curr->dev == dev)
return ilist;
curr = curr->next;
}
curr = xmalloc(sizeof(inode_list));
curr->dev = dev;
curr->inode = inode;
curr->next = ilist;
return curr;
}
static inode_list *scan_proc_net(const char *proto,
unsigned port, inode_list *ilist)
{
char path[20], line[MAX_LINE + 1];
char addr[128];
ino_t tmp_inode;
dev_t tmp_dev;
long long uint64_inode;
unsigned tmp_port;
FILE *f;
tmp_dev = find_socket_dev();
sprintf(path, "/proc/net/%s", proto);
f = fopen(path, "r");
if (!f)
return ilist;
while (fgets(line, MAX_LINE, f)) {
if (sscanf(line, "%*d: %64[0-9A-Fa-f]:%x %*x:%*x %*x %*x:%*x "
"%*x:%*x %*x %*d %*d %llu",
addr, &tmp_port, &uint64_inode) == 3
) {
if (strlen(addr) == 8 && (option_mask32 & OPT_IP6))
continue;
if (strlen(addr) > 8 && (option_mask32 & OPT_IP4))
continue;
if (tmp_port == port) {
tmp_inode = uint64_inode;
ilist = add_inode(ilist, tmp_dev, tmp_inode);
}
}
}
fclose(f);
return ilist;
}
static int search_dev_inode(inode_list *ilist, dev_t dev, ino_t inode)
{
while (ilist) {
if (ilist->dev == dev) {
if (option_mask32 & OPT_MOUNT)
return 1;
if (ilist->inode == inode)
return 1;
}
ilist = ilist->next;
}
return 0;
}
static pid_list *scan_pid_maps(const char *fname, pid_t pid,
inode_list *ilist, pid_list *plist)
{
FILE *file;
char line[MAX_LINE + 1];
int major, minor;
ino_t inode;
long long uint64_inode;
dev_t dev;
file = fopen(fname, "r");
if (!file)
return plist;
while (fgets(line, MAX_LINE, file)) {
if (sscanf(line, "%*s %*s %*s %x:%x %llu", &major, &minor, &uint64_inode) != 3)
continue;
inode = uint64_inode;
if (major == 0 && minor == 0 && inode == 0)
continue;
dev = makedev(major, minor);
if (search_dev_inode(ilist, dev, inode))
plist = add_pid(plist, pid);
}
fclose(file);
return plist;
}
static pid_list *scan_link(const char *lname, pid_t pid,
inode_list *ilist, pid_list *plist)
{
ino_t inode;
dev_t dev;
if (!file_to_dev_inode(lname, &dev, &inode))
return plist;
if (search_dev_inode(ilist, dev, inode))
plist = add_pid(plist, pid);
return plist;
}
static pid_list *scan_dir_links(const char *dname, pid_t pid,
inode_list *ilist, pid_list *plist)
{
DIR *d;
struct dirent *de;
char *lname;
d = opendir(dname);
if (!d)
return plist;
while ((de = readdir(d)) != NULL) {
lname = concat_subpath_file(dname, de->d_name);
if (lname == NULL)
continue;
plist = scan_link(lname, pid, ilist, plist);
free(lname);
}
closedir(d);
return plist;
}
/* NB: does chdir internally */
static pid_list *scan_proc_pids(inode_list *ilist)
{
DIR *d;
struct dirent *de;
pid_t pid;
pid_list *plist;
xchdir("/proc");
d = opendir("/proc");
if (!d)
return NULL;
plist = NULL;
while ((de = readdir(d)) != NULL) {
pid = (pid_t)bb_strtou(de->d_name, NULL, 10);
if (errno)
continue;
if (chdir(de->d_name) < 0)
continue;
plist = scan_link("cwd", pid, ilist, plist);
plist = scan_link("exe", pid, ilist, plist);
plist = scan_link("root", pid, ilist, plist);
plist = scan_dir_links("fd", pid, ilist, plist);
plist = scan_dir_links("lib", pid, ilist, plist);
plist = scan_dir_links("mmap", pid, ilist, plist);
plist = scan_pid_maps("maps", pid, ilist, plist);
xchdir("/proc");
}
closedir(d);
return plist;
}
static int print_pid_list(pid_list *plist)
{
while (plist != NULL) {
printf("%u ", (unsigned)plist->pid);
plist = plist->next;
}
bb_putchar('\n');
return 1;
}
static int kill_pid_list(pid_list *plist, int sig)
{
pid_t mypid = getpid();
int success = 1;
while (plist != NULL) {
if (plist->pid != mypid) {
if (kill(plist->pid, sig) != 0) {
bb_perror_msg("kill pid %u", (unsigned)plist->pid);
success = 0;
}
}
plist = plist->next;
}
return success;
}
int fuser_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int fuser_main(int argc UNUSED_PARAM, char **argv)
{
pid_list *plist;
inode_list *ilist;
char **pp;
dev_t dev;
ino_t inode;
unsigned port;
int opt;
int success;
int killsig;
/*
fuser [options] FILEs or PORT/PROTOs
Find processes which use FILEs or PORTs
-m Find processes which use same fs as FILEs
-4 Search only IPv4 space
-6 Search only IPv6 space
-s Silent: just exit with 0 if any processes are found
-k Kill found processes (otherwise display PIDs)
-SIGNAL Signal to send (default: TERM)
*/
/* Handle -SIGNAL. Oh my... */
killsig = SIGTERM;
pp = argv;
while (*++pp) {
char *arg = *pp;
if (arg[0] != '-')
continue;
if (arg[1] == '-' && arg[2] == '\0') /* "--" */
break;
if ((arg[1] == '4' || arg[1] == '6') && arg[2] == '\0')
continue; /* it's "-4" or "-6" */
opt = get_signum(&arg[1]);
if (opt < 0)
continue;
/* "-SIGNAL" option found. Remove it and bail out */
killsig = opt;
do {
pp[0] = arg = pp[1];
pp++;
} while (arg);
break;
}
opt = getopt32(argv, OPTION_STRING);
argv += optind;
ilist = NULL;
pp = argv;
while (*pp) {
char *proto = parse_net_arg(*pp, &port);
if (proto) { /* PORT/PROTO */
ilist = scan_proc_net(proto, port, ilist);
free(proto);
} else { /* FILE */
if (!file_to_dev_inode(*pp, &dev, &inode))
bb_perror_msg_and_die("can't open %s", *pp);
ilist = add_inode(ilist, dev, inode);
}
pp++;
}
plist = scan_proc_pids(ilist); /* changes dir to "/proc" */
if (!plist)
return EXIT_FAILURE;
success = 1;
if (opt & OPT_KILL) {
success = kill_pid_list(plist, killsig);
} else if (!(opt & OPT_SILENT)) {
success = print_pid_list(plist);
}
return (success != 1); /* 0 == success */
}