main.c revision 3f54fd611f536639ec30dd53c48e5ec1897cc7d9
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1982-2012 AT&T Intellectual Property *
* 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/execargs"
#include "FEATURE/externs"
#ifdef _hdr_nc
# include <nc.h>
#endif /* _hdr_nc */
#define CMD_LENGTH 64
/* These routines are referenced by this module */
static void exfile(Shell_t*, Sfio_t*,int);
static void chkmail(Shell_t *shp, char*);
#if defined(_lib_fork) && !defined(_NEXT_SOURCE)
static void fixargs(char**,int);
#else
# define fixargs(a,b)
#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 = 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;
free(malloc(64*1024));
#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->gd->pid = getpid();
shp->gd->ppid = getppid();
}
shp->fn_depth = shp->dot_depth = 0;
command = error_info.id;
/* set pidname '$$' */
srand(shp->gd->pid&0x7fff);
if(nv_isnull(PS4NOD))
nv_putval(PS4NOD,e_traceprompt,NV_RDONLY);
path_pwd(shp,1);
iop = (Sfio_t*)0;
#if SHOPT_BRACEPAT
sh_onoption(SH_BRACEEXPAND);
#endif
if((beenhere++)==0)
{
sh_onstate(SH_PROFILE);
((Lex_t*)shp->lex_context)->nonstandard = 0;
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_RC) && (sh_isoption(SH_BASH) && !sh_isoption(SH_POSIX)
#if SHOPT_REMOTE
|| !fstat(0, &statb) && REMOTE(statb.st_mode)
#endif
))
sh_onoption(SH_RC);
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 SHOPT_BASH
if(sh_isoption(SH_BASH) && !sh_isoption(SH_POSIX))
{
#if SHOPT_SYSRC
sh_source(shp, iop, e_bash_sysrc);
#endif
sh_source(shp, iop, shp->gd->rcfile ? shp->gd->rcfile : sh_mactry(shp,(char*)e_bash_rc));
}
else
#endif
{
if(name = sh_mactry(shp,nv_getval(ENVNOD)))
name = *name ? 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;
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);
#if !_WINIX
/*
* try to undo effect of solaris 2.5+
* change for argv for setuid scripts
*/
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 $0 for ps */
execv(pathshell(),av);
/* exec fails */
shp->st.dolv[0] = av[0];
fixargs(shp->st.dolv,1);
}
#endif
name = av[0];
sh_offoption(SH_VERBOSE);
sh_offoption(SH_XTRACE);
}
else
{
int isdir = 0;
if((fdin=sh_open(name,O_RDONLY,0))>=0 &&(fstat(fdin,&statb)<0 || S_ISDIR(statb.st_mode)))
{
close(fdin);
isdir = 1;
fdin = -1;
}
else
shp->st.filename = path_fullname(shp,name);
sp = 0;
if(fdin < 0 && !strchr(name,'/'))
{
#ifdef PATH_BFPATH
if(path_absolute(shp,name,NIL(Pathcomp_t*)))
sp = stakptr(PATH_OFFSET);
#else
sp = path_absolute(shp,name,NIL(char*));
#endif
if(sp)
{
if((fdin=sh_open(sp,O_RDONLY,0))>=0)
shp->st.filename = path_fullname(shp,sp);
}
}
if(fdin<0)
{
if(isdir)
errno = EISDIR;
error_info.id = av[0];
if(sp || errno!=ENOENT)
errormsg(SH_DICT,ERROR_system(ERROR_NOEXEC),e_open,name);
/* try sh -c 'name "$@"' */
sh_onoption(SH_CFLAG);
shp->comdiv = (char*)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;
shp->comdiv--;
#if SHOPT_ACCT
sh_accinit();
if(fdin != 0)
sh_accbegin(error_info.id);
#endif /* SHOPT_ACCT */
}
}
else
{
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);
/* NOTREACHED */
return(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);
sh_offoption(SH_MONITOR);
}
sh_offstate(SH_INTERACTIVE);
sh_offstate(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;
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",getpid());
#endif
}
}
errno = 0;
if(tdone || !sfreserve(iop,0,0))
{
eof_or_error:
if(sh_isstate(SH_INTERACTIVE) && !sferror(iop))
{
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;
}
if(errno==0 && sferror(iop) && --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_isoption(SH_CFLAG) &&
(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))
{
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(_lib_fork) && !defined(_NEXT_SOURCE)
/*
* fix up command line for ps command
* mode is 0 for initialization
*/
static void fixargs(char **argv, int mode)
{
#if EXECARGS
*execargs=(char *)argv;
#else
static char *buff;
static int command_len;
register char *cp;
int offset=0,size;
# ifdef PSTAT
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);
# else
if(mode==0)
{
buff = argv[0];
while(cp = *argv++)
command_len += strlen(cp)+1;
if(environ && *environ==buff+command_len)
{
for(argv=environ; cp = *argv; cp++)
{
if(command_len > CMD_LENGTH)
{
command_len = CMD_LENGTH;
break;
}
*argv++ = strdup(cp);
command_len += strlen(cp)+1;
}
}
command_len -= 1;
return;
}
# endif /* PSTAT */
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++] = ' ';
}
buff[offset-1] = 0;
# ifdef PSTAT
un.pst_command = stakptr(0);
pstat(PSTAT_SETCMD,un,0,0,0);
# endif /* PSTAT */
#endif /* EXECARGS */
}
#endif /* _lib_fork */