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authorGravatar Denis Vlasenko <vda.linux@googlemail.com>2008-07-30 21:23:26 +0000
committerGravatar Denis Vlasenko <vda.linux@googlemail.com>2008-07-30 21:23:26 +0000
commitb35714986721a6f36ecb87034e6024138f6c0b6e (patch)
treed715bf54d18c2d72b883af8053b363db347aeebd
parentc90e1be01b76aed12ef1cd77c789c842bda26ba6 (diff)
downloadbusybox-b35714986721a6f36ecb87034e6024138f6c0b6e.tar.gz
busybox-b35714986721a6f36ecb87034e6024138f6c0b6e.tar.bz2
chpst: large code shrink by Vladimir
function old new delta chpst_main 1058 1357 +299 euidgid 56 - -56 suidgid 59 - -59 slimit 208 - -208 packed_usage 24638 24420 -218 edir 375 - -375 ------------------------------------------------------------------------------ (add/remove: 0/4 grow/shrink: 1/1 up/down: 299/-916) Total: -617 bytes
-rw-r--r--include/usage.h67
-rw-r--r--runit/chpst.c373
2 files changed, 209 insertions, 231 deletions
diff --git a/include/usage.h b/include/usage.h
index 110fbf641..466dfac11 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -365,27 +365,26 @@
"-r--r--r-- 1 root root 0 Apr 12 18:25 /tmp/foo\n"
#define chpst_trivial_usage \
- "[-vP012] [-u user[:group]] [-U user[:group]] [-e dir] " \
- "[-/ dir] [-n nice] [-m bytes] [-d bytes] [-o files] " \
- "[-p processes] [-f bytes] [-c bytes] prog args"
+ "[-vP012] [-u USER[:GRP]] [-U USER[:GRP]] [-e DIR]\n" \
+ " [-/ DIR] [-n NICE] [-m BYTES] [-d BYTES] [-o N]\n" \
+ " [-p N] [-f BYTES] [-c BYTES] PROG ARGS"
#define chpst_full_usage "\n\n" \
- "Change the process state and run specified program\n" \
+ "Change the process state and run PROG\n" \
"\nOptions:" \
"\n -u USER[:GRP] Set uid and gid" \
"\n -U USER[:GRP] Set $UID and $GID in environment" \
"\n -e DIR Set environment variables as specified by files" \
"\n in DIR: file=1st_line_of_file" \
"\n -/ DIR Chroot to DIR" \
- "\n -n INC Add INC to nice value" \
- "\n -m BYTES Limit data segment, stack segment, locked physical pages," \
- "\n and total of all segment per process to BYTES each" \
+ "\n -n NICE Add NICE to nice value" \
+ "\n -m BYTES Same as -d BYTES -s BYTES -l BYTES" \
"\n -d BYTES Limit data segment" \
- "\n -o N Limit the number of open file descriptors per process to N" \
- "\n -p N Limit number of processes per uid to N" \
- "\n -f BYTES Limit output file size to BYTES" \
- "\n -c BYTES Limit core file size to BYTES" \
+ "\n -o N Limit number of open files per process" \
+ "\n -p N Limit number of processes per uid" \
+ "\n -f BYTES Limit output file sizes" \
+ "\n -c BYTES Limit core file size" \
"\n -v Verbose" \
- "\n -P Run prog in a new process group" \
+ "\n -P Create new process group" \
"\n -0 Close standard input" \
"\n -1 Close standard output" \
"\n -2 Close standard error" \
@@ -394,41 +393,37 @@
"account prog args"
#define setuidgid_full_usage "\n\n" \
"Set uid and gid to account's uid and gid, removing all supplementary\n" \
- "groups, then run prog"
+ "groups and run PROG"
#define envuidgid_trivial_usage \
"account prog args"
#define envuidgid_full_usage "\n\n" \
- "Set $UID to account's uid and $GID to account's gid, then run prog"
+ "Set $UID to account's uid and $GID to account's gid and run PROG"
#define envdir_trivial_usage \
"dir prog args"
#define envdir_full_usage "\n\n" \
"Set various environment variables as specified by files\n" \
- "in the directory dir, then run prog"
+ "in the directory dir and run PROG"
#define softlimit_trivial_usage \
- "[-a allbytes] [-c corebytes] [-d databytes] [-f filebytes] " \
- "[-l lockbytes] [-m membytes] [-o openfiles] [-p processes] " \
- "[-r residentbytes] [-s stackbytes] [-t cpusecs] prog args"
+ "[-a BYTES] [-m BYTES] [-d BYTES] [-s BYTES] [-l BYTES]\n" \
+ " [-f BYTES] [-c BYTES] [-r BYTES] [-o N] [-p N] [-t N]\n" \
+ " PROG ARGS"
#define softlimit_full_usage "\n\n" \
- "Set soft resource limits, then run prog\n" \
- "\nOptions:" \
- "\n -m n Same as -d n -s n -l n -a n" \
- "\n -d n Limit the data segment per process to n bytes" \
- "\n -s n Limit the stack segment per process to n bytes" \
- "\n -l n Limit the locked physical pages per process to n bytes" \
- "\n -a n Limit the total of all segments per process to n bytes" \
- "\n -o n Limit the number of open file descriptors per process to n" \
- "\n -p n Limit the number of processes per uid to n" \
+ "Set soft resource limits, then run PROG\n" \
+ "\nOptions:" \
+ "\n -a BYTES Limit total size of all segments" \
+ "\n -m BYTES Same as -d BYTES -s BYTES -l BYTES -a BYTES" \
+ "\n -d BYTES Limit data segment" \
+ "\n -s BYTES Limit stack segment" \
+ "\n -l BYTES Limit locked memory size" \
+ "\n -o N Limit number of open files per process" \
+ "\n -p N Limit number of processes per uid" \
"\nOptions controlling file sizes:" \
- "\n -f n Limit output file sizes to n bytes" \
- "\n -c n Limit core file sizes to n bytes" \
+ "\n -f BYTES Limit output file sizes" \
+ "\n -c BYTES Limit core file size" \
"\nEfficiency opts:" \
- "\n -r n Limit the resident set size to n bytes. This limit is not" \
- "\n enforced unless physical memory is full" \
- "\n -t n Limit the CPU time to n seconds. This limit is not enforced" \
- "\n except that the process receives a SIGXCPU signal after n seconds" \
- "\n" \
- "\nSome options may have no effect on some operating systems" \
- "\nn may be =, indicating that soft limit should be set equal to hard limit" \
+ "\n -r BYTES Limit resident set size" \
+ "\n -t N Limit CPU time, process receives" \
+ "\n a SIGXCPU after N seconds" \
#define chroot_trivial_usage \
"NEWROOT [COMMAND...]"
diff --git a/runit/chpst.c b/runit/chpst.c
index 3c841ddbb..24d1d6e2c 100644
--- a/runit/chpst.c
+++ b/runit/chpst.c
@@ -29,73 +29,68 @@ ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
/* Dependencies on runit_lib.c removed */
#include "libbb.h"
-
#include <dirent.h>
-// Must match constants in chpst_main!
-#define OPT_verbose (option_mask32 & 0x2000)
-#define OPT_pgrp (option_mask32 & 0x4000)
-#define OPT_nostdin (option_mask32 & 0x8000)
-#define OPT_nostdout (option_mask32 & 0x10000)
-#define OPT_nostderr (option_mask32 & 0x20000)
+/*
+Five applets here: chpst, envdir, envuidgid, setuidgid, softlimit.
-struct globals {
- char *set_user;
- char *env_user;
- const char *env_dir;
- const char *root;
- long limitd; /* limitX are initialized to -2 */
- long limits;
- long limitl;
- long limita;
- long limito;
- long limitp;
- long limitf;
- long limitc;
- long limitr;
- long limitt;
- int nicelvl;
-};
-#define G (*(struct globals*)&bb_common_bufsiz1)
-#define set_user (G.set_user)
-#define env_user (G.env_user)
-#define env_dir (G.env_dir )
-#define root (G.root )
-#define limitd (G.limitd )
-#define limits (G.limits )
-#define limitl (G.limitl )
-#define limita (G.limita )
-#define limito (G.limito )
-#define limitp (G.limitp )
-#define limitf (G.limitf )
-#define limitc (G.limitc )
-#define limitr (G.limitr )
-#define limitt (G.limitt )
-#define nicelvl (G.nicelvl )
-#define INIT_G() do { \
- long *p = &limitd; \
- do *p++ = -2; while (p <= &limitt); \
-} while (0)
-
-static void suidgid(char *user)
-{
- struct bb_uidgid_t ugid;
+Only softlimit and chpst are taking options:
- xget_uidgid(&ugid, user);
- if (setgroups(1, &ugid.gid) == -1)
- bb_perror_msg_and_die("setgroups");
- xsetgid(ugid.gid);
- xsetuid(ugid.uid);
-}
+# common
+-o N Limit number of open files per process
+-p N Limit number of processes per uid
+-m BYTES Same as -d BYTES -s BYTES -l BYTES [-a BYTES]
+-d BYTES Limit data segment
+-f BYTES Limit output file sizes
+-c BYTES Limit core file size
+# softlimit
+-a BYTES Limit total size of all segments
+-s BYTES Limit stack segment
+-l BYTES Limit locked memory size
+-r BYTES Limit resident set size
+-t N Limit CPU time
+# chpst
+-u USER[:GRP] Set uid and gid
+-U USER[:GRP] Set $UID and $GID in environment
+-e DIR Set environment variables as specified by files in DIR
+-/ DIR Chroot to DIR
+-n NICE Add NICE to nice value
+-v Verbose
+-P Create new process group
+-0 -1 -2 Close fd 0,1,2
-static void euidgid(char *user)
-{
- struct bb_uidgid_t ugid;
+Even though we accept all these options for both softlimit and chpst,
+they are not to be advertised on their help texts.
+We have enough problems with feature creep in other people's
+software, don't want to add our own.
- xget_uidgid(&ugid, user);
- xsetenv("GID", utoa(ugid.gid));
- xsetenv("UID", utoa(ugid.uid));
-}
+envdir, envuidgid, setuidgid take no options, but they reuse code which
+handles -e, -U and -u.
+*/
+
+enum {
+ OPT_a = (1 << 0) * ENABLE_SOFTLIMIT,
+ OPT_c = (1 << 1) * (ENABLE_SOFTLIMIT || ENABLE_CHPST),
+ OPT_d = (1 << 2) * (ENABLE_SOFTLIMIT || ENABLE_CHPST),
+ OPT_f = (1 << 3) * (ENABLE_SOFTLIMIT || ENABLE_CHPST),
+ OPT_l = (1 << 4) * ENABLE_SOFTLIMIT,
+ OPT_m = (1 << 5) * (ENABLE_SOFTLIMIT || ENABLE_CHPST),
+ OPT_o = (1 << 6) * (ENABLE_SOFTLIMIT || ENABLE_CHPST),
+ OPT_p = (1 << 7) * (ENABLE_SOFTLIMIT || ENABLE_CHPST),
+ OPT_r = (1 << 8) * ENABLE_SOFTLIMIT,
+ OPT_s = (1 << 9) * ENABLE_SOFTLIMIT,
+ OPT_t = (1 << 10) * ENABLE_SOFTLIMIT,
+ OPT_u = (1 << 11) * (ENABLE_CHPST || ENABLE_SETUIDGID),
+ OPT_U = (1 << 12) * (ENABLE_CHPST || ENABLE_ENVUIDGID),
+ OPT_e = (1 << 13) * (ENABLE_CHPST || ENABLE_ENVDIR),
+ OPT_root = (1 << 14) * ENABLE_CHPST,
+ OPT_n = (1 << 15) * ENABLE_CHPST,
+ OPT_v = (1 << 16) * ENABLE_CHPST,
+ OPT_P = (1 << 17) * ENABLE_CHPST,
+ OPT_0 = (1 << 18) * ENABLE_CHPST,
+ OPT_1 = (1 << 19) * ENABLE_CHPST,
+ OPT_2 = (1 << 20) * ENABLE_CHPST,
+};
static void edir(const char *directory_name)
{
@@ -126,8 +121,8 @@ static void edir(const char *directory_name)
continue;
fd = open(d->d_name, O_RDONLY | O_NDELAY);
if (fd < 0) {
- if ((errno == EISDIR) && env_dir) {
- if (OPT_verbose)
+ if ((errno == EISDIR) && directory_name) {
+ if (option_mask32 & OPT_v)
bb_perror_msg("warning: %s/%s is a directory",
directory_name, d->d_name);
continue;
@@ -175,229 +170,217 @@ static void limit(int what, long l)
bb_perror_msg_and_die("setrlimit");
}
-static void slimit(void)
+int chpst_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int chpst_main(int argc UNUSED_PARAM, char **argv)
{
- if (limitd >= -1) {
+ struct bb_uidgid_t ugid;
+ char *set_user;
+ char *env_user;
+ char *env_dir;
+ char *root;
+ char *nicestr;
+ unsigned limita;
+ unsigned limitc;
+ unsigned limitd;
+ unsigned limitf;
+ unsigned limitl;
+ unsigned limitm;
+ unsigned limito;
+ unsigned limitp;
+ unsigned limitr;
+ unsigned limits;
+ unsigned limitt;
+ unsigned opt;
+
+ if ((ENABLE_CHPST && applet_name[0] == 'c')
+ || (ENABLE_SOFTLIMIT && applet_name[1] == 'o')
+ ) {
+ // FIXME: can we live with int-sized limits?
+ // can we live with 40000 days?
+ // if yes -> getopt converts strings to numbers for us
+ opt_complementary = "-1:a+:c+:d+:f+:l+:m+:o+:p+:r+:s+:t+";
+ opt = getopt32(argv, "+a:c:d:f:l:m:o:p:r:s:t:u:U:e:"
+ USE_CHPST("/:n:vP012"),
+ &limita, &limitc, &limitd, &limitf, &limitl,
+ &limitm, &limito, &limitp, &limitr, &limits, &limitt,
+ &set_user, &env_user, &env_dir
+ USE_CHPST(, &root, &nicestr));
+ argv += optind;
+ if (opt & OPT_m) { // -m means -asld
+ limita = limits = limitl = limitd = limitm;
+ opt |= (OPT_s | OPT_l | OPT_a | OPT_d);
+ }
+ } else {
+ option_mask32 = opt = 0;
+ argv++;
+ }
+
+ // envdir?
+ if (ENABLE_ENVDIR && applet_name[3] == 'd') {
+ env_dir = *argv++;
+ opt |= OPT_e;
+ }
+
+ // setuidgid?
+ if (ENABLE_SETUIDGID && applet_name[0] == 's') {
+ set_user = *argv++;
+ opt |= OPT_u;
+ }
+
+ // envuidgid?
+ if (ENABLE_ENVUIDGID && applet_name[0] == 'e') {
+ env_user = *argv++;
+ opt |= OPT_U;
+ }
+
+ // we must have PROG [ARGS]
+ if (!*argv)
+ bb_show_usage();
+
+ // set limits
+ if (opt & OPT_d) {
#ifdef RLIMIT_DATA
limit(RLIMIT_DATA, limitd);
#else
- if (OPT_verbose)
+ if (opt & OPT_v)
bb_error_msg("system does not support RLIMIT_%s",
"DATA");
#endif
}
- if (limits >= -1) {
+ if (opt & OPT_s) {
#ifdef RLIMIT_STACK
limit(RLIMIT_STACK, limits);
#else
- if (OPT_verbose)
+ if (opt & OPT_v)
bb_error_msg("system does not support RLIMIT_%s",
"STACK");
#endif
}
- if (limitl >= -1) {
+ if (opt & OPT_l) {
#ifdef RLIMIT_MEMLOCK
limit(RLIMIT_MEMLOCK, limitl);
#else
- if (OPT_verbose)
+ if (opt & OPT_v)
bb_error_msg("system does not support RLIMIT_%s",
"MEMLOCK");
#endif
}
- if (limita >= -1) {
+ if (opt & OPT_a) {
#ifdef RLIMIT_VMEM
limit(RLIMIT_VMEM, limita);
#else
#ifdef RLIMIT_AS
limit(RLIMIT_AS, limita);
#else
- if (OPT_verbose)
+ if (opt & OPT_v)
bb_error_msg("system does not support RLIMIT_%s",
"VMEM");
#endif
#endif
}
- if (limito >= -1) {
+ if (opt & OPT_o) {
#ifdef RLIMIT_NOFILE
limit(RLIMIT_NOFILE, limito);
#else
#ifdef RLIMIT_OFILE
limit(RLIMIT_OFILE, limito);
#else
- if (OPT_verbose)
+ if (opt & OPT_v)
bb_error_msg("system does not support RLIMIT_%s",
"NOFILE");
#endif
#endif
}
- if (limitp >= -1) {
+ if (opt & OPT_p) {
#ifdef RLIMIT_NPROC
limit(RLIMIT_NPROC, limitp);
#else
- if (OPT_verbose)
+ if (opt & OPT_v)
bb_error_msg("system does not support RLIMIT_%s",
"NPROC");
#endif
}
- if (limitf >= -1) {
+ if (opt & OPT_f) {
#ifdef RLIMIT_FSIZE
limit(RLIMIT_FSIZE, limitf);
#else
- if (OPT_verbose)
+ if (opt & OPT_v)
bb_error_msg("system does not support RLIMIT_%s",
"FSIZE");
#endif
}
- if (limitc >= -1) {
+ if (opt & OPT_c) {
#ifdef RLIMIT_CORE
limit(RLIMIT_CORE, limitc);
#else
- if (OPT_verbose)
+ if (opt & OPT_v)
bb_error_msg("system does not support RLIMIT_%s",
"CORE");
#endif
}
- if (limitr >= -1) {
+ if (opt & OPT_r) {
#ifdef RLIMIT_RSS
limit(RLIMIT_RSS, limitr);
#else
- if (OPT_verbose)
+ if (opt & OPT_v)
bb_error_msg("system does not support RLIMIT_%s",
"RSS");
#endif
}
- if (limitt >= -1) {
+ if (opt & OPT_t) {
#ifdef RLIMIT_CPU
limit(RLIMIT_CPU, limitt);
#else
- if (OPT_verbose)
+ if (opt & OPT_v)
bb_error_msg("system does not support RLIMIT_%s",
"CPU");
#endif
}
-}
-/* argv[0] */
-static void setuidgid(int, char **) NORETURN;
-static void envuidgid(int, char **) NORETURN;
-static void envdir(int, char **) NORETURN;
-static void softlimit(int, char **) NORETURN;
+ if (opt & OPT_P)
+ setsid();
-int chpst_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int chpst_main(int argc UNUSED_PARAM, char **argv)
-{
- INIT_G();
-
- if (applet_name[3] == 'd') envdir(argc, argv);
- if (applet_name[1] == 'o') softlimit(argc, argv);
- if (applet_name[0] == 's') setuidgid(argc, argv);
- if (applet_name[0] == 'e') envuidgid(argc, argv);
- // otherwise we are chpst
-
- {
- char *m,*d,*o,*p,*f,*c,*r,*t,*n;
- getopt32(argv, "+u:U:e:m:d:o:p:f:c:r:t:/:n:vP012",
- &set_user,&env_user,&env_dir,
- &m,&d,&o,&p,&f,&c,&r,&t,&root,&n);
- // if (option_mask32 & 0x1) // -u
- // if (option_mask32 & 0x2) // -U
- // if (option_mask32 & 0x4) // -e
- if (option_mask32 & 0x8) limits = limitl = limita = limitd = xatoul(m); // -m
- if (option_mask32 & 0x10) limitd = xatoul(d); // -d
- if (option_mask32 & 0x20) limito = xatoul(o); // -o
- if (option_mask32 & 0x40) limitp = xatoul(p); // -p
- if (option_mask32 & 0x80) limitf = xatoul(f); // -f
- if (option_mask32 & 0x100) limitc = xatoul(c); // -c
- if (option_mask32 & 0x200) limitr = xatoul(r); // -r
- if (option_mask32 & 0x400) limitt = xatoul(t); // -t
- // if (option_mask32 & 0x800) // -/
- if (option_mask32 & 0x1000) nicelvl = xatoi(n); // -n
- // The below consts should match #defines at top!
- //if (option_mask32 & 0x2000) OPT_verbose = 1; // -v
- //if (option_mask32 & 0x4000) OPT_pgrp = 1; // -P
- //if (option_mask32 & 0x8000) OPT_nostdin = 1; // -0
- //if (option_mask32 & 0x10000) OPT_nostdout = 1; // -1
- //if (option_mask32 & 0x20000) OPT_nostderr = 1; // -2
+ if (opt & OPT_e)
+ edir(env_dir);
+
+ // FIXME: chrooted jail must have /etc/passwd if we move this after chroot!
+ // OTOH chroot fails for non-roots!
+ // SOLUTION: cache uid/gid before chroot, apply uid/gid after
+ if (opt & OPT_U) {
+ xget_uidgid(&ugid, env_user);
+ xsetenv("GID", utoa(ugid.gid));
+ xsetenv("UID", utoa(ugid.uid));
}
- argv += optind;
- if (!argv || !*argv) bb_show_usage();
- if (OPT_pgrp) setsid();
- if (env_dir) edir(env_dir);
- if (root) {
+ if (opt & OPT_u) {
+ xget_uidgid(&ugid, set_user);
+ }
+
+ if (opt & OPT_root) {
xchdir(root);
xchroot(".");
}
- slimit();
- if (nicelvl) {
+
+ if (opt & OPT_u) {
+ if (setgroups(1, &ugid.gid) == -1)
+ bb_perror_msg_and_die("setgroups");
+ xsetgid(ugid.gid);
+ xsetuid(ugid.uid);
+ }
+
+ if (opt & OPT_n) {
errno = 0;
- if (nice(nicelvl) == -1)
+ if (nice(xatoi(nicestr)) == -1)
bb_perror_msg_and_die("nice");
}
- if (env_user) euidgid(env_user);
- if (set_user) suidgid(set_user);
- if (OPT_nostdin) close(0);
- if (OPT_nostdout) close(1);
- if (OPT_nostderr) close(2);
- BB_EXECVP(argv[0], argv);
- bb_perror_msg_and_die("exec %s", argv[0]);
-}
-
-static void setuidgid(int argc UNUSED_PARAM, char **argv)
-{
- const char *account;
-
- account = *++argv;
- if (!account) bb_show_usage();
- if (!*++argv) bb_show_usage();
- suidgid((char*)account);
- BB_EXECVP(argv[0], argv);
- bb_perror_msg_and_die("exec %s", argv[0]);
-}
-
-static void envuidgid(int argc UNUSED_PARAM, char **argv)
-{
- const char *account;
- account = *++argv;
- if (!account) bb_show_usage();
- if (!*++argv) bb_show_usage();
- euidgid((char*)account);
- BB_EXECVP(argv[0], argv);
- bb_perror_msg_and_die("exec %s", argv[0]);
-}
+ if (opt & OPT_0)
+ close(STDIN_FILENO);
+ if (opt & OPT_1)
+ close(STDOUT_FILENO);
+ if (opt & OPT_2)
+ close(STDERR_FILENO);
-static void envdir(int argc UNUSED_PARAM, char **argv)
-{
- const char *dir;
-
- dir = *++argv;
- if (!dir) bb_show_usage();
- if (!*++argv) bb_show_usage();
- edir(dir);
- BB_EXECVP(argv[0], argv);
- bb_perror_msg_and_die("exec %s", argv[0]);
-}
-
-static void softlimit(int argc UNUSED_PARAM, char **argv)
-{
- char *a,*c,*d,*f,*l,*m,*o,*p,*r,*s,*t;
- getopt32(argv, "+a:c:d:f:l:m:o:p:r:s:t:",
- &a,&c,&d,&f,&l,&m,&o,&p,&r,&s,&t);
- if (option_mask32 & 0x001) limita = xatoul(a); // -a
- if (option_mask32 & 0x002) limitc = xatoul(c); // -c
- if (option_mask32 & 0x004) limitd = xatoul(d); // -d
- if (option_mask32 & 0x008) limitf = xatoul(f); // -f
- if (option_mask32 & 0x010) limitl = xatoul(l); // -l
- if (option_mask32 & 0x020) limits = limitl = limita = limitd = xatoul(m); // -m
- if (option_mask32 & 0x040) limito = xatoul(o); // -o
- if (option_mask32 & 0x080) limitp = xatoul(p); // -p
- if (option_mask32 & 0x100) limitr = xatoul(r); // -r
- if (option_mask32 & 0x200) limits = xatoul(s); // -s
- if (option_mask32 & 0x400) limitt = xatoul(t); // -t
- argv += optind;
- if (!argv[0]) bb_show_usage();
- slimit();
BB_EXECVP(argv[0], argv);
bb_perror_msg_and_die("exec %s", argv[0]);
}