/***********************************************************************
* *
* 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
/*
* test expression
* [ expression ]
*
* David Korn
* AT&T Labs
*
*/
#include "defs.h"
#include <error.h>
#include <ls.h>
#include <regex.h>
#include "io.h"
#include "terminal.h"
#include "test.h"
#include "builtins.h"
#include "FEATURE/externs"
#include "FEATURE/poll"
#include <tmx.h>
#if !_lib_setregid
# undef _lib_setreuid
#endif /* _lib_setregid */
#ifdef S_ISSOCK
# if _pipe_socketpair
# if _socketpair_shutdown_mode
# define isapipe(f,p) (test_stat(f,p)>=0&&S_ISFIFO((p)->st_mode)||S_ISSOCK((p)->st_mode)&&(p)->st_ino&&((p)->st_mode&(S_IRUSR|S_IWUSR))!=(S_IRUSR|S_IWUSR))
# else
# define isapipe(f,p) (test_stat(f,p)>=0&&S_ISFIFO((p)->st_mode)||S_ISSOCK((p)->st_mode)&&(p)->st_ino)
# endif
# else
# define isapipe(f,p) (test_stat(f,p)>=0&&S_ISFIFO((p)->st_mode)||S_ISSOCK((p)->st_mode)&&(p)->st_ino)
# endif
# define isasock(f,p) (test_stat(f,p)>=0&&S_ISSOCK((p)->st_mode))
#else
# define isapipe(f,p) (test_stat(f,p)>=0&&S_ISFIFO((p)->st_mode))
# define isasock(f,p) (0)
#endif
#define permission(a,f) (sh_access(a,f)==0)
static time_t test_time(const char*, const char*);
static int test_stat(const char*, struct stat*);
static int test_mode(const char*);
/* single char string compare */
#define c_eq(a,c) (*a==c && *(a+1)==0)
/* two character string compare */
#define c2_eq(a,c1,c2) (*a==c1 && *(a+1)==c2 && *(a+2)==0)
struct test
{
Shell_t *sh;
int ap;
int ac;
char **av;
};
static char *nxtarg(struct test*,int);
static int expr(struct test*,int);
static int e3(struct test*);
static int test_strmatch(Shell_t *shp,const char *str, const char *pat)
{
regoff_t match[2*(MATCH_MAX+1)],n;
register int c, m=0;
register const char *cp=pat;
while(c = *cp++)
{
if(c=='(')
m++;
if(c=='\\' && *cp)
cp++;
}
if(m)
m++;
else
match[0] = 0;
if(m > elementsof(match)/2)
m = elementsof(match)/2;
n = strgrpmatch(str, pat, match, m, STR_GROUP|STR_MAXIMAL|STR_LEFT|STR_RIGHT);
if(m==0 && n==1)
match[1] = strlen(str);
if(n)
sh_setmatch(shp, str, -1, n, match, 0);
return(n);
}
int b_test(int argc, char *argv[],Shbltin_t *context)
{
struct test tdata;
register char *cp = argv[0];
register int not;
tdata.sh = context->shp;
tdata.av = argv;
tdata.ap = 1;
if(c_eq(cp,'['))
{
cp = argv[--argc];
if(!c_eq(cp, ']'))
errormsg(SH_DICT,ERROR_exit(2),e_missing,"']'");
}
if(argc <= 1)
return(1);
cp = argv[1];
if(c_eq(cp,'(') && argc<=6 && c_eq(argv[argc-1],')'))
{
/* special case ( binop ) to conform with standard */
if(!(argc==4 && (not=sh_lookup(cp=argv[2],shtab_testops))))
{
cp = (++argv)[1];
argc -= 2;
}
}
not = c_eq(cp,'!');
/* posix portion for test */
switch(argc)
{
case 5:
if(!not)
break;
argv++;
/* fall through */
case 4:
{
register int op = sh_lookup(cp=argv[2],shtab_testops);
if(op&TEST_BINOP)
break;
if(!op)
{
if(argc==5)
break;
if(not && cp[0]=='-' && cp[2]==0)
return(test_unop(tdata.sh,cp[1],argv[3])!=0);
else if(argv[1][0]=='-' && argv[1][2]==0)
return(!test_unop(tdata.sh,argv[1][1],cp));
else if(not && c_eq(argv[2],'!'))
return(*argv[3]==0);
errormsg(SH_DICT,ERROR_exit(2),e_badop,cp);
}
return(test_binop(tdata.sh,op,argv[1],argv[3])^(argc!=5));
}
case 3:
if(not)
return(*argv[2]!=0);
if(cp[0] != '-' || cp[2] || cp[1]=='?')
{
if(cp[0]=='-' && (cp[1]=='-' || cp[1]=='?') &&
strcmp(argv[2],"--")==0)
{
char *av[3];
av[0] = argv[0];
av[1] = argv[1];
av[2] = 0;
optget(av,sh_opttest);
errormsg(SH_DICT,ERROR_usage(2), "%s",opt_info.arg);
return(2);
}
break;
}
return(!test_unop(tdata.sh,cp[1],argv[2]));
case 2:
return(*cp==0);
}
tdata.ac = argc;
return(!expr(&tdata,0));
}
/*
* evaluate a test expression.
* flag is 0 on outer level
* flag is 1 when in parenthesis
* flag is 2 when evaluating -a
*/
static int expr(struct test *tp,register int flag)
{
register int r;
register char *p;
r = e3(tp);
while(tp->ap < tp->ac)
{
p = nxtarg(tp,0);
/* check for -o and -a */
if(flag && c_eq(p,')'))
{
tp->ap--;
break;
}
if(*p=='-' && *(p+2)==0)
{
if(*++p == 'o')
{
if(flag==2)
{
tp->ap--;
break;
}
r |= expr(tp,3);
continue;
}
else if(*p == 'a')
{
r &= expr(tp,2);
continue;
}
}
if(flag==0)
break;
errormsg(SH_DICT,ERROR_exit(2),e_badsyntax);
}
return(r);
}
static char *nxtarg(struct test *tp,int mt)
{
if(tp->ap >= tp->ac)
{
if(mt)
{
tp->ap++;
return(0);
}
errormsg(SH_DICT,ERROR_exit(2),e_argument);
}
return(tp->av[tp->ap++]);
}
static int e3(struct test *tp)
{
register char *arg, *cp;
register int op;
char *binop;
arg=nxtarg(tp,0);
if(arg && c_eq(arg, '!'))
return(!e3(tp));
if(c_eq(arg, '('))
{
op = expr(tp,1);
cp = nxtarg(tp,0);
if(!cp || !c_eq(cp, ')'))
errormsg(SH_DICT,ERROR_exit(2),e_missing,"')'");
return(op);
}
cp = nxtarg(tp,1);
if(cp!=0 && (c_eq(cp,'=') || c2_eq(cp,'!','=')))
goto skip;
if(c2_eq(arg,'-','t'))
{
if(cp)
{
op = strtol(cp,&binop, 10);
return(*binop?0:tty_check(op));
}
else
{
/* test -t with no arguments */
tp->ap--;
return(tty_check(1));
}
}
if(*arg=='-' && arg[2]==0)
{
op = arg[1];
if(!cp)
{
/* for backward compatibility with new flags */
if(op==0 || !strchr(test_opchars+10,op))
return(1);
errormsg(SH_DICT,ERROR_exit(2),e_argument);
}
if(strchr(test_opchars,op))
return(test_unop(tp->sh,op,cp));
}
if(!cp)
{
tp->ap--;
return(*arg!=0);
}
skip:
op = sh_lookup(binop=cp,shtab_testops);
if(!(op&TEST_BINOP))
cp = nxtarg(tp,0);
if(!op)
errormsg(SH_DICT,ERROR_exit(2),e_badop,binop);
if(op==TEST_AND || op==TEST_OR)
tp->ap--;
return(test_binop(tp->sh,op,arg,cp));
}
int test_unop(Shell_t *shp,register int op,register const char *arg)
{
struct stat statb;
int f;
switch(op)
{
case 'r':
return(permission(arg, R_OK));
case 'w':
return(permission(arg, W_OK));
case 'x':
return(permission(arg, X_OK));
case 'V':
#if SHOPT_FS_3D
{
register int offset = staktell();
if(stat(arg,&statb)<0 || !S_ISREG(statb.st_mode))
return(0);
/* add trailing / */
stakputs(arg);
stakputc('/');
stakputc(0);
arg = (const char*)stakptr(offset);
stakseek(offset);
/* FALL THRU */
}
#else
return(0);
#endif /* SHOPT_FS_3D */
case 'd':
return(test_stat(arg,&statb)>=0 && S_ISDIR(statb.st_mode));
case 'c':
return(test_stat(arg,&statb)>=0 && S_ISCHR(statb.st_mode));
case 'b':
return(test_stat(arg,&statb)>=0 && S_ISBLK(statb.st_mode));
case 'f':
return(test_stat(arg,&statb)>=0 && S_ISREG(statb.st_mode));
case 'u':
return(test_mode(arg)&S_ISUID);
case 'g':
return(test_mode(arg)&S_ISGID);
case 'k':
#ifdef S_ISVTX
return(test_mode(arg)&S_ISVTX);
#else
return(0);
#endif /* S_ISVTX */
#if SHOPT_TEST_L
case 'l':
#endif
case 'L':
case 'h': /* undocumented, and hopefully will disappear */
if(*arg==0 || arg[strlen(arg)-1]=='/' || lstat(arg,&statb)<0)
return(0);
return(S_ISLNK(statb.st_mode));
case 'C':
#ifdef S_ISCTG
return(test_stat(arg,&statb)>=0 && S_ISCTG(statb.st_mode));
#else
return(0);
#endif /* S_ISCTG */
case 'H':
#ifdef S_ISCDF
{
register int offset = staktell();
if(test_stat(arg,&statb)>=0 && S_ISCDF(statb.st_mode))
return(1);
stakputs(arg);
stakputc('+');
stakputc(0);
arg = (const char*)stakptr(offset);
stakseek(offset);
return(test_stat(arg,&statb)>=0 && S_ISCDF(statb.st_mode));
}
#else
return(0);
#endif /* S_ISCDF */
case 'S':
return(isasock(arg,&statb));
case 'N':
return(test_stat(arg,&statb)>=0 && tmxgetmtime(&statb) > tmxgetatime(&statb));
case 'p':
return(isapipe(arg,&statb));
case 'n':
return(*arg != 0);
case 'z':
return(*arg == 0);
case 's':
sfsync(sfstdout);
case 'O':
case 'G':
if(*arg==0 || test_stat(arg,&statb)<0)
return(0);
if(op=='s')
return(statb.st_size>0);
else if(op=='O')
return(statb.st_uid==shp->gd->userid);
return(statb.st_gid==shp->gd->groupid);
case 'a':
case 'e':
if(memcmp(arg,"/dev/",5)==0 && sh_open(arg,O_NONBLOCK))
return(1);
return(permission(arg, F_OK));
case 'o':
f=1;
if(*arg=='?')
return(sh_lookopt(arg+1,&f)>0);
op = sh_lookopt(arg,&f);
return(op && (f==(sh_isoption(op)!=0)));
case 't':
{
char *last;
op = strtol(arg,&last, 10);
return(*last?0:tty_check(op));
}
case 'v':
case 'R':
{
Namval_t *np;
Namarr_t *ap;
int isref;
if(!(np = nv_open(arg,shp->var_tree,NV_VARNAME|NV_NOFAIL|NV_NOADD|NV_NOREF)))
return(0);
isref = nv_isref(np);
if(op=='R')
return(isref);
if(isref)
{
if(np->nvalue.cp)
np = nv_refnode(np);
else
return(0);
}
if(ap = nv_arrayptr(np))
return(nv_arrayisset(np,ap));
return(!nv_isnull(np) || nv_isattr(np,NV_INTEGER));
}
default:
{
static char a[3] = "-?";
a[1]= op;
errormsg(SH_DICT,ERROR_exit(2),e_badop,a);
/* NOTREACHED */
return(0);
}
}
}
int test_binop(Shell_t *shp,register int op,const char *left,const char *right)
{
register double lnum,rnum;
if(op&TEST_ARITH)
{
while(*left=='0')
left++;
while(*right=='0')
right++;
lnum = sh_arith(shp,left);
rnum = sh_arith(shp,right);
}
switch(op)
{
/* op must be one of the following values */
case TEST_AND:
case TEST_OR:
return(*left!=0);
case TEST_PEQ:
return(test_strmatch(shp, left, right));
case TEST_PNE:
return(!test_strmatch(shp, left, right));
case TEST_SGT:
return(strcoll(left, right)>0);
case TEST_SLT:
return(strcoll(left, right)<0);
case TEST_SEQ:
return(strcmp(left, right)==0);
case TEST_SNE:
return(strcmp(left, right)!=0);
case TEST_EF:
return(test_inode(left,right));
case TEST_NT:
return(test_time(left,right)>0);
case TEST_OT:
return(test_time(left,right)<0);
case TEST_EQ:
return(lnum==rnum);
case TEST_NE:
return(lnum!=rnum);
case TEST_GT:
return(lnum>rnum);
case TEST_LT:
return(lnum<rnum);
case TEST_GE:
return(lnum>=rnum);
case TEST_LE:
return(lnum<=rnum);
}
/* NOTREACHED */
return(0);
}
/*
* returns the modification time of f1 - modification time of f2
*/
static time_t test_time(const char *file1,const char *file2)
{
Time_t t1, t2;
struct stat statb1,statb2;
int r=test_stat(file2,&statb2);
if(test_stat(file1,&statb1)<0)
return(r<0?0:-1);
if(r<0)
return(1);
t1 = tmxgetmtime(&statb1);
t2 = tmxgetmtime(&statb2);
if (t1 > t2)
return(1);
if (t1 < t2)
return(-1);
return(0);
}
/*
* return true if inode of two files are the same
*/
int test_inode(const char *file1,const char *file2)
{
struct stat stat1,stat2;
if(test_stat(file1,&stat1)>=0 && test_stat(file2,&stat2)>=0)
if(stat1.st_dev == stat2.st_dev && stat1.st_ino == stat2.st_ino)
return(1);
return(0);
}
/*
* This version of access checks against effective uid/gid
* The static buffer statb is shared with test_mode.
*/
int sh_access(register const char *name, register int mode)
{
Shell_t *shp = sh_getinterp();
struct stat statb;
if(*name==0)
return(-1);
if(sh_isdevfd(name))
return(sh_ioaccess((int)strtol(name+8, (char**)0, 10),mode));
/* can't use access function for execute permission with root */
if(mode==X_OK && shp->gd->euserid==0)
goto skip;
if(shp->gd->userid==shp->gd->euserid && shp->gd->groupid==shp->gd->egroupid)
return(access(name,mode));
#ifdef _lib_setreuid
/* swap the real uid to effective, check access then restore */
/* first swap real and effective gid, if different */
if(shp->gd->groupid==shp->gd->euserid || setregid(shp->gd->egroupid,shp->gd->groupid)==0)
{
/* next swap real and effective uid, if needed */
if(shp->gd->userid==shp->gd->euserid || setreuid(shp->gd->euserid,shp->gd->userid)==0)
{
mode = access(name,mode);
/* restore ids */
if(shp->gd->userid!=shp->gd->euserid)
setreuid(shp->gd->userid,shp->gd->euserid);
if(shp->gd->groupid!=shp->gd->egroupid)
setregid(shp->gd->groupid,shp->gd->egroupid);
return(mode);
}
else if(shp->gd->groupid!=shp->gd->egroupid)
setregid(shp->gd->groupid,shp->gd->egroupid);
}
#endif /* _lib_setreuid */
skip:
if(test_stat(name, &statb) == 0)
{
if(mode == F_OK)
return(mode);
else if(shp->gd->euserid == 0)
{
if(!S_ISREG(statb.st_mode) || mode!=X_OK)
return(0);
/* root needs execute permission for someone */
mode = (S_IXUSR|S_IXGRP|S_IXOTH);
}
else if(shp->gd->euserid == statb.st_uid)
mode <<= 6;
else if(shp->gd->egroupid == statb.st_gid)
mode <<= 3;
#ifdef _lib_getgroups
/* on some systems you can be in several groups */
else
{
static int maxgroups;
gid_t *groups;
register int n;
if(maxgroups==0)
{
/* first time */
if((maxgroups=getgroups(0,(gid_t*)0)) <= 0)
{
/* pre-POSIX system */
maxgroups=NGROUPS_MAX;
}
}
groups = (gid_t*)stakalloc((maxgroups+1)*sizeof(gid_t));
n = getgroups(maxgroups,groups);
while(--n >= 0)
{
if(groups[n] == statb.st_gid)
{
mode <<= 3;
break;
}
}
}
# endif /* _lib_getgroups */
if(statb.st_mode & mode)
return(0);
}
return(-1);
}
/*
* Return the mode bits of file <file>
* If <file> is null, then the previous stat buffer is used.
* The mode bits are zero if the file doesn't exist.
*/
static int test_mode(register const char *file)
{
struct stat statb;
statb.st_mode = 0;
if(file && (*file==0 || test_stat(file,&statb)<0))
return(0);
return(statb.st_mode);
}
/*
* do an fstat() for /dev/fd/n, otherwise stat()
*/
static int test_stat(const char *name,struct stat *buff)
{
if(*name==0)
{
errno = ENOENT;
return(-1);
}
if(sh_isdevfd(name))
return(fstat((int)strtol(name+8, (char**)0, 10),buff));
else
return(stat(name,buff));
}