busybox/util-linux/ipcrm.c
Denys Vlasenko 4eed2c6c50 Update menuconfig items with approximate applet sizes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-07-18 22:01:24 +02:00

239 lines
5.2 KiB
C

/* vi: set sw=4 ts=4: */
/*
* ipcrm.c - utility to allow removal of IPC objects and data structures.
*
* 01 Sept 2004 - Rodney Radford <rradford@mindspring.com>
* Adapted for busybox from util-linux-2.12a.
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//config:config IPCRM
//config: bool "ipcrm (2.9 kb)"
//config: default y
//config: help
//config: The ipcrm utility allows the removal of System V interprocess
//config: communication (IPC) objects and the associated data structures
//config: from the system.
//applet:IF_IPCRM(APPLET(ipcrm, BB_DIR_USR_BIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_IPCRM) += ipcrm.o
//usage:#define ipcrm_trivial_usage
//usage: "[-MQS key] [-mqs id]"
//usage:#define ipcrm_full_usage "\n\n"
//usage: "Upper-case options MQS remove an object by shmkey value.\n"
//usage: "Lower-case options remove an object by shmid value.\n"
//usage: "\n -mM Remove memory segment after last detach"
//usage: "\n -qQ Remove message queue"
//usage: "\n -sS Remove semaphore"
#include "libbb.h"
/* X/OPEN tells us to use <sys/{types,ipc,sem}.h> for semctl() */
/* X/OPEN tells us to use <sys/{types,ipc,msg}.h> for msgctl() */
#include <sys/ipc.h>
#include <sys/shm.h>
#include <sys/msg.h>
#include <sys/sem.h>
#if defined(__GNU_LIBRARY__) && !defined(_SEM_SEMUN_UNDEFINED)
/* union semun is defined by including <sys/sem.h> */
#else
/* according to X/OPEN we have to define it ourselves */
union semun {
int val;
struct semid_ds *buf;
unsigned short *array;
struct seminfo *__buf;
};
#endif
#define IPCRM_LEGACY 1
#if IPCRM_LEGACY
typedef enum type_id {
SHM,
SEM,
MSG
} type_id;
static int remove_ids(type_id type, char **argv)
{
unsigned long id;
int nb_errors = 0;
union semun arg;
arg.val = 0;
while (argv[0]) {
id = bb_strtoul(argv[0], NULL, 10);
if (errno || id > INT_MAX) {
bb_error_msg("invalid id: %s", argv[0]);
nb_errors++;
} else {
int ret = 0;
if (type == SEM)
ret = semctl(id, 0, IPC_RMID, arg);
else if (type == MSG)
ret = msgctl(id, IPC_RMID, NULL);
else if (type == SHM)
ret = shmctl(id, IPC_RMID, NULL);
if (ret) {
bb_perror_msg("can't remove id %s", argv[0]);
nb_errors++;
}
}
argv++;
}
return nb_errors;
}
#endif /* IPCRM_LEGACY */
int ipcrm_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int ipcrm_main(int argc, char **argv)
{
int c;
int error = 0;
/* if the command is executed without parameters, do nothing */
if (argc == 1)
return 0;
#if IPCRM_LEGACY
/* check to see if the command is being invoked in the old way if so
then run the old code. Valid commands are msg, shm, sem. */
{
type_id what = 0; /* silence gcc */
char w;
w = argv[1][0];
if ( ((w == 'm' && argv[1][1] == 's' && argv[1][2] == 'g')
|| (argv[1][0] == 's'
&& ((w = argv[1][1]) == 'h' || w == 'e')
&& argv[1][2] == 'm')
) && argv[1][3] == '\0'
) {
if (argc < 3)
bb_show_usage();
if (w == 'h')
what = SHM;
else if (w == 'm')
what = MSG;
else if (w == 'e')
what = SEM;
if (remove_ids(what, &argv[2]))
fflush_stdout_and_exit(EXIT_FAILURE);
puts("resource(s) deleted");
return 0;
}
}
#endif /* IPCRM_LEGACY */
/* process new syntax to conform with SYSV ipcrm */
while ((c = getopt(argc, argv, "q:m:s:Q:M:S:h?")) != -1) {
int result;
int id = 0;
int iskey = isupper(c);
/* needed to delete semaphores */
union semun arg;
arg.val = 0;
if ((c == '?') || (c == 'h')) {
bb_show_usage();
}
/* we don't need case information any more */
c = tolower(c);
/* make sure the option is in range: allowed are q, m, s */
if (c != 'q' && c != 'm' && c != 's') {
bb_show_usage();
}
if (iskey) {
/* keys are in hex or decimal */
key_t key = xstrtoul(optarg, 0);
if (key == IPC_PRIVATE) {
error++;
bb_error_msg("illegal key (%s)", optarg);
continue;
}
/* convert key to id */
id = ((c == 'q') ? msgget(key, 0) :
(c == 'm') ? shmget(key, 0, 0) : semget(key, 0, 0));
if (id < 0) {
const char *errmsg;
error++;
switch (errno) {
case EACCES:
errmsg = "permission denied for";
break;
case EIDRM:
errmsg = "already removed";
break;
case ENOENT:
errmsg = "invalid";
break;
default:
errmsg = "unknown error in";
break;
}
bb_error_msg("%s %s (%s)", errmsg, "key", optarg);
continue;
}
} else {
/* ids are in decimal */
id = xatoul(optarg);
}
result = ((c == 'q') ? msgctl(id, IPC_RMID, NULL) :
(c == 'm') ? shmctl(id, IPC_RMID, NULL) :
semctl(id, 0, IPC_RMID, arg));
if (result) {
const char *errmsg;
const char *const what = iskey ? "key" : "id";
error++;
switch (errno) {
case EACCES:
case EPERM:
errmsg = "permission denied for";
break;
case EINVAL:
errmsg = "invalid";
break;
case EIDRM:
errmsg = "already removed";
break;
default:
errmsg = "unknown error in";
break;
}
bb_error_msg("%s %s (%s)", errmsg, what, optarg);
continue;
}
}
/* print usage if we still have some arguments left over */
if (optind != argc) {
bb_show_usage();
}
/* exit value reflects the number of errors encountered */
return error;
}