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cde/src/cmd/ksh93/sh/main.c
Martijn Dekker fcd9efce7f Interactive: Avoid losing the job after suspending a subshell 
Reproducer: run vi in a subshell:

	$ (vi)

vi opens; now press Ctrl+Z to suspend. The output is as expected:

	[2] + Stopped                  (vi)

…but the exit status is 18 (SIGTSTP's signal number) instead of 0.

Now do:

	$ fg
	(vi)
	$

The exit status is 18 again, vi is not resumed, and the job is
lost. You have to find vi's pid manually using ps and kill it.

Forking all non-command substitution subshells invoked from the
interactive main shell is the only reliable and effective fix I've
found. I've tried to fork the subshell conditionally in every other
remotely plausible place I can think of in fault.c and xec.c, but I
can't get anything to work properly. If anyone can get this to work
without forking as much (or at all), please do submit a patch or PR
that supersedes this fix.

At least subshells of subshells don't need to fork, so the
performance impact can be limited. Plus, it's not as if most people
need maximum speed on the interactive command line. Scripts
(including login/profile scripts) are not affected at all.

Command substitutions can be handled differently. My testing shows
that all shells except ksh93 simply block SIGTSTP (the ^Z signal)
while they run. We should do the same, so they don't need to fork.

NOTE for any backporters: the subshell.c and fault.c changes depend
on commits 35b02626 and 48ba6964 to work correctly.

src/cmd/ksh93/sh/subshell.c: sh_subshell():
- If the interactive shell state bit is on, then before executing
  the subshell's code:
  - for command substitutions, block SIGTSTP;
  - for other subshells, fork.
- For command substitutions, release SIGTSTP if the interactive
  shell state bit was on upon invoking the subshell.

src/cmd/ksh93/sh/fault.c:
- Instead of checking for a virtual subshell, check the shell's
  interactive state bit to decide whether to handle SIGTSTP, as
  that is only turned on in the interactive main shell.

src/cmd/ksh93/sh/main.c: sh_main():
- To avoid bugs, ignore SIGTSTP while running profile scripts.
  Blocking it doesn't work because delaying it until after
  sigrelease() will cause a crash. Thanks to @JohnoKing for this.
- While we're here, prevent a possible overflow of the 'beenhere'
  static char variable by only incrementing it once.

Co-authored-by: Johnothan King <johnothanking@protonmail.com>
Resolves: https://github.com/ksh93/ksh/issues/390
2021-12-22 05:09:17 +00:00

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/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1982-2012 AT&T Intellectual Property *
* Copyright (c) 2020-2021 Contributors to ksh 93u+m *
* and is licensed under the *
* Eclipse Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.eclipse.org/org/documents/epl-v10.html *
* (with md5 checksum b35adb5213ca9657e911e9befb180842) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* David Korn <dgk@research.att.com> *
* *
***********************************************************************/
#pragma prototyped
/*
* UNIX shell
*
* S. R. Bourne
* Rewritten By David Korn
* AT&T Labs
*
*/
#include <ast.h>
#include <sfio.h>
#include <stak.h>
#include <ls.h>
#include <fcin.h>
#include "defs.h"
#include "variables.h"
#include "path.h"
#include "io.h"
#include "jobs.h"
#include "shlex.h"
#include "shnodes.h"
#include "history.h"
#include "timeout.h"
#include "FEATURE/time"
#include "FEATURE/pstat"
#include "FEATURE/setproctitle"
#include "FEATURE/execargs"
#include "FEATURE/externs"
#ifdef _hdr_nc
# include <nc.h>
#endif /* _hdr_nc */
/* These routines are referenced by this module */
static void exfile(Shell_t*, Sfio_t*,int);
static void chkmail(Shell_t *shp, char*);
#if !defined(_NEXT_SOURCE) && !defined(__sun)
static void fixargs(char**,int);
# undef fixargs_disabled
#else
# define fixargs(a,b)
# define fixargs_disabled 1
#endif
#ifndef environ
extern char **environ;
#endif
static struct stat lastmail;
static time_t mailtime;
static char beenhere = 0;
#ifdef _lib_sigvec
void clearsigmask(register int sig)
{
struct sigvec vec;
if(sigvec(sig,NIL(struct sigvec*),&vec)>=0 && vec.sv_mask)
{
vec.sv_mask = 0;
sigvec(sig,&vec,NIL(struct sigvec*));
}
}
#endif /* _lib_sigvec */
#ifdef PATH_BFPATH
#define PATHCOMP NIL(Pathcomp_t*)
#else
#define PATHCOMP ""
#endif
/*
* search for file and exfile() it if it exists
* 1 returned if file found, 0 otherwise
*/
int sh_source(Shell_t *shp, Sfio_t *iop, const char *file)
{
char* oid;
char* nid;
int fd;
if (!file || !*file || (fd = path_open(shp,file, PATHCOMP)) < 0)
{
REGRESS(source, "sh_source", ("%s:ENOENT", file));
return 0;
}
oid = error_info.id;
nid = error_info.id = sh_strdup(file);
shp->st.filename = path_fullname(shp,stakptr(PATH_OFFSET));
REGRESS(source, "sh_source", ("%s", file));
exfile(shp, iop, fd);
error_info.id = oid;
free(nid);
return 1;
}
#ifdef S_ISSOCK
#define REMOTE(m) (S_ISSOCK(m)||!(m))
#else
#define REMOTE(m) !(m)
#endif
int sh_main(int ac, char *av[], Shinit_f userinit)
{
register char *name;
register int fdin;
register Sfio_t *iop;
register Shell_t *shp;
struct stat statb;
int i, rshflag; /* set for restricted shell */
char *command;
#ifdef _lib_sigvec
/* This is to clear mask that may be left on by rlogin */
clearsigmask(SIGALRM);
clearsigmask(SIGHUP);
clearsigmask(SIGCHLD);
#endif /* _lib_sigvec */
#ifdef _hdr_nc
_NutConf(_NC_SET_SUFFIXED_SEARCHING, 1);
#endif /* _hdr_nc */
fixargs(av,0);
shp = sh_init(ac,av,userinit);
time(&mailtime);
if(rshflag=sh_isoption(SH_RESTRICTED))
sh_offoption(SH_RESTRICTED);
if(sigsetjmp(*((sigjmp_buf*)shp->jmpbuffer),0))
{
/* begin script execution here */
sh_reinit((char**)0);
}
shp->fn_depth = shp->dot_depth = 0;
command = error_info.id;
if(nv_isnull(PS4NOD))
nv_putval(PS4NOD,e_traceprompt,NV_RDONLY);
path_pwd(shp,1);
iop = (Sfio_t*)0;
if(sh_isoption(SH_POSIX))
sh_onoption(SH_LETOCTAL);
#if SHOPT_BRACEPAT
else
sh_onoption(SH_BRACEEXPAND);
#endif
if(!beenhere)
{
beenhere++;
sh_onstate(SH_PROFILE);
shp->sigflag[SIGTSTP] |= SH_SIGIGNORE;
if(shp->gd->ppid==1)
shp->login_sh++;
if(shp->login_sh >= 2)
sh_onoption(SH_LOGIN_SHELL);
/* decide whether shell is interactive */
if(!sh_isoption(SH_INTERACTIVE) && !sh_isoption(SH_TFLAG) && !sh_isoption(SH_CFLAG) &&
sh_isoption(SH_SFLAG) && tty_check(0) && tty_check(ERRIO))
sh_onoption(SH_INTERACTIVE);
if(sh_isoption(SH_INTERACTIVE))
{
sh_onoption(SH_BGNICE);
sh_onoption(SH_RC);
if(!sh_isoption(SH_POSIX))
{
/* preset aliases for interactive non-POSIX ksh */
dtclose(shp->alias_tree);
shp->alias_tree = sh_inittree(shp,shtab_aliases);
dtuserdata(shp->alias_tree,shp,1);
}
}
#if SHOPT_REMOTE
/*
* Building ksh with SHOPT_REMOTE=1 causes ksh to set --rc if stdin is
* a socket (presumably part of a remote shell invocation).
*/
if(!sh_isoption(SH_RC) && !fstat(0, &statb) && REMOTE(statb.st_mode))
sh_onoption(SH_RC);
#endif
for(i=0; i<elementsof(shp->offoptions.v); i++)
shp->options.v[i] &= ~shp->offoptions.v[i];
if(sh_isoption(SH_INTERACTIVE))
{
#ifdef SIGXCPU
signal(SIGXCPU,SIG_DFL);
#endif /* SIGXCPU */
#ifdef SIGXFSZ
signal(SIGXFSZ,SIG_DFL);
#endif /* SIGXFSZ */
sh_onoption(SH_MONITOR);
}
job_init(shp,sh_isoption(SH_LOGIN_SHELL));
if(sh_isoption(SH_LOGIN_SHELL))
{
/* system profile */
sh_source(shp, iop, e_sysprofile);
if(!sh_isoption(SH_NOUSRPROFILE) && !sh_isoption(SH_PRIVILEGED))
{
char **files = shp->gd->login_files;
while ((name = *files++) && !sh_source(shp, iop, sh_mactry(shp,name)));
}
}
/* make sure PWD is set up correctly */
path_pwd(shp,1);
if(!sh_isoption(SH_NOEXEC))
{
if(!sh_isoption(SH_NOUSRPROFILE) && !sh_isoption(SH_PRIVILEGED) && sh_isoption(SH_RC))
{
if(name = sh_mactry(shp,nv_getval(ENVNOD)))
name = *name ? sh_strdup(name) : (char*)0;
#if SHOPT_SYSRC
if(!strmatch(name, "?(.)/./*"))
sh_source(shp, iop, e_sysrc);
#endif
if(name)
{
sh_source(shp, iop, name);
free(name);
}
}
else if(sh_isoption(SH_INTERACTIVE) && sh_isoption(SH_PRIVILEGED))
sh_source(shp, iop, e_suidprofile);
}
shp->st.cmdname = error_info.id = command;
shp->sigflag[SIGTSTP] &= ~(SH_SIGIGNORE);
sh_offstate(SH_PROFILE);
if(rshflag)
sh_onoption(SH_RESTRICTED);
/* open input file if specified */
if(shp->comdiv)
{
shell_c:
iop = sfnew(NIL(Sfio_t*),shp->comdiv,strlen(shp->comdiv),0,SF_STRING|SF_READ);
}
else
{
name = error_info.id;
error_info.id = shp->shname;
if(sh_isoption(SH_SFLAG))
fdin = 0;
else
{
char *sp;
/* open stream should have been passed into shell */
if(strmatch(name,e_devfdNN))
{
#if !_WINIX
char *cp;
int type;
#endif
fdin = (int)strtol(name+8, (char**)0, 10);
if(fstat(fdin,&statb)<0)
{
errormsg(SH_DICT,ERROR_system(1),e_open,name);
UNREACHABLE();
}
#if !_WINIX
/*
* try to undo effect of Solaris 2.5+
* change for argv for setuid scripts
*/
if(shp->st.repl_index > 0)
av[shp->st.repl_index] = shp->st.repl_arg;
if(((type = sh_type(cp = av[0])) & SH_TYPE_SH) && (name = nv_getval(L_ARGNOD)) && (!((type = sh_type(cp = name)) & SH_TYPE_SH)))
{
av[0] = (type & SH_TYPE_LOGIN) ? cp : path_basename(cp);
/* exec to change $0 for ps */
execv(pathshell(),av);
/* exec fails */
shp->st.dolv[0] = av[0];
fixargs(shp->st.dolv,1);
}
#endif
name = av[0];
sh_offoption(SH_VERBOSE);
sh_offoption(SH_XTRACE);
}
else
{
int isdir = 0;
if((fdin=sh_open(name,O_RDONLY,0))>=0 &&(fstat(fdin,&statb)<0 || S_ISDIR(statb.st_mode)))
{
close(fdin);
isdir = 1;
fdin = -1;
}
else
shp->st.filename = path_fullname(shp,name);
sp = 0;
if(fdin < 0 && !strchr(name,'/'))
{
#ifdef PATH_BFPATH
if(path_absolute(shp,name,NIL(Pathcomp_t*),0))
sp = stakptr(PATH_OFFSET);
#else
sp = path_absolute(shp,name,NIL(char*));
#endif
if(sp)
{
if((fdin=sh_open(sp,O_RDONLY,0))>=0)
shp->st.filename = path_fullname(shp,sp);
}
}
if(fdin<0)
{
if(isdir)
errno = EISDIR;
error_info.id = av[0];
if(sp || errno!=ENOENT)
{
errormsg(SH_DICT,ERROR_system(ERROR_NOEXEC),e_open,name);
UNREACHABLE();
}
/* try sh -c 'name "$@"' */
sh_onoption(SH_CFLAG);
shp->comdiv = (char*)sh_malloc(strlen(name)+7);
name = strcopy(shp->comdiv,name);
if(shp->st.dolc)
strcopy(name," \"$@\"");
goto shell_c;
}
if(fdin==0)
fdin = sh_iomovefd(fdin);
}
shp->readscript = shp->shname;
}
error_info.id = name;
#if SHOPT_ACCT
sh_accinit();
if(fdin != 0)
sh_accbegin(error_info.id);
#endif /* SHOPT_ACCT */
}
/* If the shell is initialised with std{in,out,err} closed, make the shell's FD state reflect that. */
for(i=0; i<=2; i++)
if(fcntl(i,F_GETFD,NiL)==-1 && errno==EBADF) /* closed at OS level? */
sh_close(i); /* update shell FD state */
}
else
{
/* beenhere > 0: We're in a forked child, about to execute a script without a hashbang path. */
fdin = shp->infd;
fixargs(shp->st.dolv,1);
}
if(sh_isoption(SH_INTERACTIVE))
sh_onstate(SH_INTERACTIVE);
nv_putval(IFSNOD,(char*)e_sptbnl,NV_RDONLY);
exfile(shp,iop,fdin);
sh_done(shp,0);
}
/*
* iop is not null when the input is a string
* fdin is the input file descriptor
*/
static void exfile(register Shell_t *shp, register Sfio_t *iop,register int fno)
{
time_t curtime;
Shnode_t *t;
int maxtry=IOMAXTRY, tdone=0, execflags;
int states,jmpval;
struct checkpt buff;
sh_pushcontext(shp,&buff,SH_JMPERREXIT);
/* open input stream */
nv_putval(SH_PATHNAMENOD, shp->st.filename ,NV_NOFREE);
if(!iop)
{
if(fno > 0)
{
int r;
if(fno < 10 && ((r=sh_fcntl(fno,F_DUPFD,10))>=10))
{
shp->fdstatus[r] = shp->fdstatus[fno];
sh_close(fno);
fno = r;
}
fcntl(fno,F_SETFD,FD_CLOEXEC);
shp->fdstatus[fno] |= IOCLEX;
iop = sh_iostream((void*)shp,fno);
}
else
iop = sfstdin;
}
else
fno = -1;
shp->infd = fno;
if(sh_isstate(SH_INTERACTIVE))
{
if(nv_isnull(PS1NOD))
nv_putval(PS1NOD,(shp->gd->euserid?e_stdprompt:e_supprompt),NV_RDONLY);
sh_sigdone();
if(sh_histinit((void*)shp))
sh_onoption(SH_HISTORY);
}
else
{
if(!sh_isstate(SH_PROFILE))
{
buff.mode = SH_JMPEXIT;
sh_onoption(SH_TRACKALL);
}
if(sh_isoption(SH_MONITOR))
sh_onstate(SH_MONITOR);
sh_offstate(SH_HISTORY);
sh_offoption(SH_HISTORY);
}
states = sh_getstate();
jmpval = sigsetjmp(buff.buff,0);
if(jmpval)
{
Sfio_t *top;
sh_iorestore((void*)shp,0,jmpval);
hist_flush(shp->gd->hist_ptr);
sfsync(shp->outpool);
shp->st.execbrk = shp->st.breakcnt = 0;
/* check for return from profile or env file */
if(sh_isstate(SH_PROFILE) && (jmpval==SH_JMPFUN || jmpval==SH_JMPEXIT))
{
sh_setstate(states);
goto done;
}
if(!sh_isoption(SH_INTERACTIVE) || sh_isstate(SH_FORKED) || (jmpval > SH_JMPERREXIT && job_close(shp) >=0))
{
sh_offstate(SH_INTERACTIVE);
sh_offstate(SH_MONITOR);
goto done;
}
exitset();
/* skip over remaining input */
if(top = fcfile())
{
while(fcget()>0);
fcclose();
while(top=sfstack(iop,SF_POPSTACK))
sfclose(top);
}
/* make sure that we own the terminal */
#ifdef SIGTSTP
tcsetpgrp(job.fd,shp->gd->pid);
#endif /* SIGTSTP */
}
/* error return here */
sfclrerr(iop);
sh_setstate(states);
shp->st.optindex = 1;
opt_info.offset = 0;
shp->st.loopcnt = 0;
shp->trapnote = 0;
shp->intrap = 0;
error_info.line = 1;
shp->inlineno = 1;
shp->binscript = 0;
shp->exittrap = 0;
shp->errtrap = 0;
shp->end_fn = 0;
if(sfeof(iop))
goto eof_or_error;
/* command loop */
while(1)
{
shp->nextprompt = 1;
sh_freeup(shp);
stakset(NIL(char*),0);
sh_offstate(SH_STOPOK);
sh_offstate(SH_ERREXIT);
sh_offstate(SH_VERBOSE);
sh_offstate(SH_TIMING);
sh_offstate(SH_GRACE);
sh_offstate(SH_TTYWAIT);
if(sh_isoption(SH_VERBOSE))
sh_onstate(SH_VERBOSE);
sh_onstate(SH_ERREXIT);
/* -eim flags don't apply to profiles */
if(sh_isstate(SH_PROFILE))
{
sh_offstate(SH_INTERACTIVE);
sh_offstate(SH_ERREXIT);
sh_offstate(SH_MONITOR);
}
if(sh_isstate(SH_INTERACTIVE) && !tdone)
{
register char *mail;
#ifdef JOBS
sh_offstate(SH_MONITOR);
if(sh_isoption(SH_MONITOR))
sh_onstate(SH_MONITOR);
if(job.pwlist)
{
job_walk(sfstderr,job_list,JOB_NFLAG,(char**)0);
job_wait((pid_t)0);
}
#endif /* JOBS */
if((mail=nv_getval(MAILPNOD)) || (mail=nv_getval(MAILNOD)))
{
time(&curtime);
if ((curtime - mailtime) >= sh_mailchk)
{
chkmail(shp,mail);
mailtime = curtime;
}
}
if(shp->gd->hist_ptr)
hist_eof(shp->gd->hist_ptr);
/* sets timeout for command entry */
shp->timeout = shp->st.tmout;
#if SHOPT_TIMEOUT
if(shp->timeout <= 0 || shp->timeout > SHOPT_TIMEOUT)
shp->timeout = SHOPT_TIMEOUT;
#endif /* SHOPT_TIMEOUT */
shp->inlineno = 1;
error_info.line = 1;
shp->trapnote = 0;
if(buff.mode == SH_JMPEXIT)
{
buff.mode = SH_JMPERREXIT;
#ifdef DEBUG
errormsg(SH_DICT,ERROR_warn(0),"%d: mode changed to JMP_EXIT",shgd->current_pid);
#endif
}
}
errno = 0;
if(tdone || !sfreserve(iop,0,0))
{
int sferr;
eof_or_error:
sferr = sferror(iop);
if(sh_isstate(SH_INTERACTIVE))
{
if(!sferr)
{
if(--maxtry>0 && sh_isoption(SH_IGNOREEOF)
&& !sferror(sfstderr) && (shp->fdstatus[fno]&IOTTY))
{
sfclrerr(iop);
errormsg(SH_DICT,0,e_logout);
continue;
}
else if(job_close(shp)<0)
continue;
}
else if(sferr==SH_EXITSIG)
{
/* Ctrl+C with SIGINT ignored */
sfputc(sfstderr,'\n');
continue;
}
}
if(errno==0 && sferr && --maxtry>0)
{
sfclrlock(iop);
sfclrerr(iop);
continue;
}
goto done;
}
shp->exitval = sh.savexit;
maxtry = IOMAXTRY;
if(sh_isstate(SH_INTERACTIVE) && shp->gd->hist_ptr)
{
job_wait((pid_t)0);
hist_eof(shp->gd->hist_ptr);
sfsync(sfstderr);
}
if(sh_isoption(SH_HISTORY))
sh_onstate(SH_HISTORY);
job.waitall = job.curpgid = 0;
error_info.flags |= ERROR_INTERACTIVE;
t = (Shnode_t*)sh_parse(shp,iop,0);
if(!sh_isstate(SH_INTERACTIVE) && !sh_isoption(SH_CFLAG))
error_info.flags &= ~ERROR_INTERACTIVE;
shp->readscript = 0;
if(sh_isstate(SH_INTERACTIVE) && shp->gd->hist_ptr)
hist_flush(shp->gd->hist_ptr);
sh_offstate(SH_HISTORY);
if(t)
{
execflags = sh_state(SH_ERREXIT)|sh_state(SH_INTERACTIVE);
/* The last command may not have to fork */
if(!sh_isstate(SH_PROFILE) && !sh_isstate(SH_INTERACTIVE) &&
(fno<0 || !(shp->fdstatus[fno]&(IOTTY|IONOSEEK)))
&& !sfreserve(iop,0,0))
{
execflags |= sh_state(SH_NOFORK);
}
shp->st.execbrk = 0;
sh_exec(t,execflags);
if(shp->forked)
{
sh_offstate(SH_INTERACTIVE);
goto done;
}
/* This is for sh -t */
if(sh_isoption(SH_TFLAG) && !sh_isstate(SH_PROFILE))
tdone++;
}
}
done:
sh_popcontext(shp,&buff);
if(sh_isstate(SH_INTERACTIVE))
{
if(isatty(0) && !sh_isoption(SH_CFLAG))
sfputc(sfstderr,'\n');
job_close(shp);
}
if(jmpval == SH_JMPSCRIPT)
siglongjmp(*shp->jmplist,jmpval);
else if(jmpval == SH_JMPEXIT)
sh_done(shp,0);
if(fno>0)
sh_close(fno);
if(shp->st.filename)
free((void*)shp->st.filename);
shp->st.filename = 0;
}
/* prints out messages if files in list have been modified since last call */
static void chkmail(Shell_t *shp, char *files)
{
register char *cp,*sp,*qp;
register char save;
struct argnod *arglist=0;
int offset = staktell();
char *savstak=stakptr(0);
struct stat statb;
if(*(cp=files) == 0)
return;
sp = cp;
do
{
/* skip to : or end of string saving first '?' */
for(qp=0;*sp && *sp != ':';sp++)
if((*sp == '?' || *sp=='%') && qp == 0)
qp = sp;
save = *sp;
*sp = 0;
/* change '?' to end-of-string */
if(qp)
*qp = 0;
do
{
/* see if time has been modified since last checked
* and the access time <= the modification time
*/
if(stat(cp,&statb) >= 0 && statb.st_mtime >= mailtime
&& statb.st_atime <= statb.st_mtime)
{
/* check for directory */
if(!arglist && S_ISDIR(statb.st_mode))
{
/* generate list of directory entries */
path_complete(shp,cp,"/*",&arglist);
}
else
{
/*
* If the file has shrunk,
* or if the size is zero
* then don't print anything
*/
if(statb.st_size &&
( statb.st_ino != lastmail.st_ino
|| statb.st_dev != lastmail.st_dev
|| statb.st_size > lastmail.st_size))
{
/* save and restore $_ */
char *save = shp->lastarg;
shp->lastarg = cp;
errormsg(SH_DICT,0,sh_mactry(shp,qp?qp+1:(char*)e_mailmsg));
shp->lastarg = save;
}
lastmail = statb;
break;
}
}
if(arglist)
{
cp = arglist->argval;
arglist = arglist->argchn.ap;
}
else
cp = 0;
}
while(cp);
if(qp)
*qp = '?';
*sp++ = save;
cp = sp;
}
while(save);
stakset(savstak,offset);
}
#undef EXECARGS
#undef PSTAT
#if defined(_hdr_execargs) && defined(pdp11)
# include <execargs.h>
# define EXECARGS 1
#endif
#if defined(_lib_pstat) && defined(_sys_pstat)
# include <sys/pstat.h>
# define PSTAT 1
#endif
#if !defined(fixargs_disabled)
/*
* fix up command line for ps command
*
* This function is invoked when ksh needs to run a script without a
* #!/hashbang/path. Instead of letting the kernel invoke a shell, ksh
* exfile()s the script itself from sh_main(). In the forked child, it calls
* fixargs() to set the argument list in the environment to the args of the
* new script, so that 'ps' and /proc/PID/cmdline show the expected output.
*
* mode is 0 for initialization
*/
static void fixargs(char **argv, int mode)
{
# if EXECARGS
if(mode==0)
return;
*execargs=(char *)argv;
# elif PSTAT
char *cp;
int offset=0,size;
static int command_len;
char *buff;
union pstun un;
if(mode==0)
{
struct pst_static st;
un.pst_static = &st;
if(pstat(PSTAT_STATIC, un, sizeof(struct pst_static), 1, 0)<0)
return;
command_len = st.command_length;
return;
}
stakseek(command_len+2);
buff = stakseek(0);
if(command_len==0)
return;
while((cp = *argv++) && offset < command_len)
{
if(offset + (size=strlen(cp)) >= command_len)
size = command_len - offset;
memcpy(buff+offset,cp,size);
offset += size;
buff[offset++] = ' ';
}
offset--;
memset(&buff[offset], 0, command_len - offset + 1);
un.pst_command = stakptr(0);
pstat(PSTAT_SETCMD,un,0,0,0);
# elif _lib_setproctitle
# define CMDMAXLEN 255
char *cp;
int offset=0,size;
char buff[CMDMAXLEN + 1];
if(mode==0)
return;
while((cp = *argv++) && offset < CMDMAXLEN)
{
if(offset + (size=strlen(cp)) >= CMDMAXLEN)
size = CMDMAXLEN - offset;
memcpy(buff+offset,cp,size);
offset += size;
buff[offset++] = ' ';
}
buff[--offset] = '\0';
setproctitle("%s",buff);
# undef CMDMAXLEN
# else
/* Generic version, works on at least Linux and macOS */
char *cp;
int offset=0,size;
static int buffsize;
static char *buff;
if(mode==0)
{
int i;
buff = argv[0];
for(i=0; argv[i]; i++)
buffsize += strlen(argv[i]) + 1;
if(buffsize < 128 && buff + buffsize == *environ)
{
/* Move the environment to make space for a larger command line buffer */
for(i=0; environ[i]; i++)
{
buffsize += strlen(environ[i]) + 1;;
environ[i] = sh_strdup(environ[i]);
}
}
return;
}
while((cp = *argv++) && offset < buffsize)
{
if(offset + (size=strlen(cp)) >= buffsize)
size = buffsize - offset;
memcpy(buff+offset,cp,size);
offset += size;
buff[offset++] = ' ';
}
offset--;
memset(&buff[offset], 0, buffsize - offset + 1);
# endif
}
#endif /* !fixargs_disabled */
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