trap.c revision da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1982-2007 AT&T Knowledge Ventures *
* and is licensed under the *
* Common Public License, Version 1.0 *
* by AT&T Knowledge Ventures *
* *
* A copy of the License is available at *
* http://www.opensource.org/licenses/cpl1.0.txt *
* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* David Korn <dgk@research.att.com> *
* *
***********************************************************************/
#pragma prototyped
/*
* trap [-p] action sig...
* kill [-l] [sig...]
* kill [-s sig] pid...
*
* David Korn
* AT&T Labs
* research!dgk
*
*/
#include "defs.h"
#include <ctype.h>
#include "jobs.h"
#include "builtins.h"
#define L_FLAG 1
#define S_FLAG 2
static const char trapfmt[] = "trap -- %s %s\n";
static int sig_number(const char*);
static void sig_list(Shell_t*,int);
int b_trap(int argc,char *argv[],void *extra)
{
register char *arg = argv[1];
register int sig, pflag = 0;
register Shell_t *shp = (Shell_t*)extra;
NOT_USED(argc);
while (sig = optget(argv, sh_opttrap)) switch (sig)
{
case 'p':
pflag=1;
break;
case ':':
errormsg(SH_DICT,2, "%s", opt_info.arg);
break;
case '?':
errormsg(SH_DICT,ERROR_usage(0), "%s", opt_info.arg);
return(2);
break;
}
argv += opt_info.index;
if(error_info.errors)
errormsg(SH_DICT,ERROR_usage(2),"%s", optusage((char*)0));
if(arg = *argv)
{
register int clear;
char *action = arg;
if(!pflag)
{
/* first argument all digits or - means clear */
while(isdigit(*arg))
arg++;
clear = (arg!=action && *arg==0);
if(!clear)
{
++argv;
if(*action=='-' && action[1]==0)
clear++;
}
while(!argv[0])
errormsg(SH_DICT,ERROR_exit(1),e_condition);
}
while(arg = *argv++)
{
sig = sig_number(arg);
if(sig<0)
{
errormsg(SH_DICT,2,e_trap,arg);
return(1);
}
/* internal traps */
if(sig&SH_TRAP)
{
sig &= ~SH_TRAP;
if(sig>SH_DEBUGTRAP)
{
errormsg(SH_DICT,2,e_trap,arg);
return(1);
}
if(pflag)
{
if(arg=shp->st.trap[sig])
sfputr(sfstdout,sh_fmtq(arg),'\n');
continue;
}
if(shp->st.trap[sig])
free(shp->st.trap[sig]);
shp->st.trap[sig] = 0;
if(!clear && *action)
shp->st.trap[sig] = strdup(action);
if(sig == SH_DEBUGTRAP)
{
if(shp->st.trap[sig])
shp->trapnote |= SH_SIGTRAP;
else
shp->trapnote = 0;
}
continue;
}
if(sig>shp->sigmax)
{
errormsg(SH_DICT,2,e_trap,arg);
return(1);
}
else if(pflag)
{
char **trapcom = (shp->st.otrapcom?shp->st.otrapcom:shp->st.trapcom);
if(arg=trapcom[sig])
sfputr(sfstdout,arg,'\n');
}
else if(clear)
sh_sigclear(sig);
else
{
if(sig >= shp->st.trapmax)
shp->st.trapmax = sig+1;
if(arg=shp->st.trapcom[sig])
free(arg);
shp->st.trapcom[sig] = strdup(action);
sh_sigtrap(sig);
}
}
}
else /* print out current traps */
sig_list(shp,-1);
return(0);
}
int b_kill(int argc,char *argv[],void *extra)
{
register char *signame;
register int sig=SIGTERM, flag=0, n;
register Shell_t *shp = (Shell_t*)extra;
NOT_USED(argc);
while((n = optget(argv,sh_optkill))) switch(n)
{
case ':':
if((signame=argv[opt_info.index++]) && (sig=sig_number(signame+1))>=0)
goto endopts;
opt_info.index--;
errormsg(SH_DICT,2, "%s", opt_info.arg);
break;
case 'n':
sig = (int)opt_info.num;
goto endopts;
case 's':
flag |= S_FLAG;
signame = opt_info.arg;
goto endopts;
case 'l':
flag |= L_FLAG;
break;
case '?':
errormsg(SH_DICT,ERROR_usage(2), "%s", opt_info.arg);
break;
}
endopts:
argv += opt_info.index;
if(*argv && strcmp(*argv,"--")==0 && strcmp(*(argv-1),"--")!=0)
argv++;
if(error_info.errors || flag==(L_FLAG|S_FLAG) || (!(*argv) && !(flag&L_FLAG)))
errormsg(SH_DICT,ERROR_usage(2),"%s", optusage((char*)0));
/* just in case we send a kill -9 $$ */
sfsync(sfstderr);
if(flag&L_FLAG)
{
if(!(*argv))
sig_list(shp,0);
else while(signame = *argv++)
{
if(isdigit(*signame))
sig_list(shp,((int)strtol(signame, (char**)0, 10)&0177)+1);
else
{
if((sig=sig_number(signame))<0)
{
shp->exitval = 2;
errormsg(SH_DICT,ERROR_exit(1),e_nosignal,signame);
}
sfprintf(sfstdout,"%d\n",sig);
}
}
return(shp->exitval);
}
if(flag&S_FLAG)
{
if((sig=sig_number(signame)) < 0 || sig > shp->sigmax)
errormsg(SH_DICT,ERROR_exit(1),e_nosignal,signame);
}
if(job_walk(sfstdout,job_kill,sig,argv))
shp->exitval = 1;
return(shp->exitval);
}
/*
* Given the name or number of a signal return the signal number
*/
static int sig_number(const char *string)
{
const Shtable_t *tp;
register int n,sig=0;
char *last;
if(isdigit(*string))
{
n = strtol(string,&last,10);
if(*last)
n = -1;
}
else
{
register int c;
n = staktell();
do
{
c = *string++;
if(islower(c))
c = toupper(c);
stakputc(c);
}
while(c);
stakseek(n);
if(memcmp(stakptr(n),"SIG",3)==0)
{
sig = 1;
n += 3;
}
tp = sh_locate(stakptr(n),(const Shtable_t*)shtab_signals,sizeof(*shtab_signals));
n = tp->sh_number;
if(sig==1 && (n>=(SH_TRAP-1) && n < (1<<SH_SIGBITS)))
{
/* sig prefix cannot match internal traps */
n = 0;
tp = (Shtable_t*)((char*)tp + sizeof(*shtab_signals));
if(strcmp(stakptr(n),tp->sh_name)==0)
n = tp->sh_number;
}
n &= (1<<SH_SIGBITS)-1;
if(n < SH_TRAP)
n--;
}
return(n);
}
/*
* if <flag> is positive, then print signal name corresponding to <flag>
* if <flag> is zero, then print all signal names
* if <flag> is negative, then print all traps
*/
static void sig_list(register Shell_t *shp,register int flag)
{
register const struct shtable2 *tp;
register int sig = shp->sigmax+1;
const char *names[SH_TRAP];
const char *traps[SH_DEBUGTRAP+1];
tp=shtab_signals;
if(flag==0)
{
/* not all signals may be defined, so initialize */
while(--sig >= 0)
names[sig] = 0;
for(sig=SH_DEBUGTRAP; sig>=0; sig--)
traps[sig] = 0;
}
while(*tp->sh_name)
{
sig = tp->sh_number;
sig &= ((1<<SH_SIGBITS)-1);
if(sig==flag)
{
sfprintf(sfstdout,"%s\n",tp->sh_name);
return;
}
else if(sig&SH_TRAP)
traps[sig&~SH_TRAP] = (char*)tp->sh_name;
else if(sig < sizeof(names)/sizeof(char*))
names[sig] = (char*)tp->sh_name;
tp++;
}
if(flag > 0)
sfprintf(sfstdout,"%d\n",flag-1);
else if(flag<0)
{
/* print the traps */
register char *trap,*sname,**trapcom;
char name[6];
sig = shp->st.trapmax;
/* use parent traps if otrapcom is set (for $(trap) */
trapcom = (shp->st.otrapcom?shp->st.otrapcom:shp->st.trapcom);
while(--sig >= 0)
{
if(!(trap=trapcom[sig]))
continue;
if(!(sname=(char*)names[sig+1]))
{
sname = name;
sname[0] = 'S';
sname[1] = 'I';
sname[2] = 'G';
sname[3] = (sig/10)+'0';
sname[4] = (sig%10)+'0';
}
sfprintf(sfstdout,trapfmt,sh_fmtq(trap),sname);
}
for(sig=SH_DEBUGTRAP; sig>=0; sig--)
{
if(!(trap=shp->st.trap[sig]))
continue;
sfprintf(sfstdout,trapfmt,sh_fmtq(trap),traps[sig]);
}
}
else
{
/* print all the signal names */
for(sig=2; sig <= shp->sigmax; sig++)
{
if(names[sig])
sfputr(sfstdout,names[sig],'\n');
else
sfprintf(sfstdout,"SIG%d\n",sig-1);
}
}
}