Remove code related to long-dead 3DFS research project

This commit gets rid of dead weight related to an obscure early
1990s Bell Labs versioning file system research project called
3DFS, which has not existed for decades and for which I have not
managed to find any evidence that it was ever used outside the lab.

This removes:
- the SHOPT_FS_3D compile option (which was forced on even when 0)
- the obnoxious default alias 2d='set -f;_2d' that turned off your
  globbing and then tried to run a nonexistent _2d command
- undocumented builtins 'vmap' and 'vpath' that only errored out
- a non-functional -V unary operator for the test and [[ commands
- some specific code for Apollo workstations (last made in 1997),
  which was inseparably intertwined with the 3DFS code

(cherry picked from commit 20cdf3709f4fb4e468057b534dcee819b1961fb6)

src/cmd/ksh93/sh/init.c

@@ -181,9 +181,6 @@ struct match
 typedef struct _init_
 {
 	Shell_t		*sh;
-#if SHOPT_FS_3D
-	Namfun_t	VPATH_init;
-#endif /* SHOPT_FS_3D */
 	struct ifs	IFS_init;
 	Namfun_t	PATH_init;
 	Namfun_t	FPATH_init;
@@ -923,41 +920,6 @@ static Sfdouble_t nget_version(register Namval_t* np, Namfun_t *fp)
 
 static const Namdisc_t SH_VERSION_disc	= {  0, 0, get_version, nget_version };
 
-#if SHOPT_FS_3D
-    /*
-     * set or unset the mappings given a colon separated list of directories
-     */
-    static void vpath_set(char *str, int mode)
-    {
-	register char *lastp, *oldp=str, *newp=strchr(oldp,':');
-	if(!shgd->lim.fs3d)
-		return;
-	while(newp)
-	{
-		*newp++ = 0;
-		if(lastp=strchr(newp,':'))
-			*lastp = 0;
-		mount((mode?newp:""),oldp,FS3D_VIEW,0);
-		newp[-1] = ':';
-		oldp = newp;
-		newp=lastp;
-	}
-    }
-
-    /* catch vpath assignments */
-    static void put_vpath(register Namval_t* np,const char *val,int flags,Namfun_t *fp)
-    {
-	register char *cp;
-	if(cp = nv_getval(np))
-		vpath_set(cp,0);
-	if(val)
-		vpath_set((char*)val,1);
-	nv_putv(np,val,flags,fp);
-    }
-    static const Namdisc_t VPATH_disc	= { 0, put_vpath  };
-    static Namfun_t VPATH_init	= { &VPATH_disc, 1  };
-#endif /* SHOPT_FS_3D */
-
 
 static const Namdisc_t IFS_disc		= {  sizeof(struct ifs), put_ifs, get_ifs };
 const Namdisc_t RESTRICTED_disc	= {  sizeof(Namfun_t), put_restricted };
@@ -1296,10 +1258,6 @@ Shell_t *sh_init(register int argc,register char *argv[], Shinit_f userinit)
 			shgd->lim.child_max = CHILD_MAX;
 		if(shgd->lim.clk_tck <=0)
 			shgd->lim.clk_tck = CLK_TCK;
-#if SHOPT_FS_3D
-		if(fs3d(FS3D_TEST))
-			shgd->lim.fs3d = 1;
-#endif /* SHOPT_FS_3D */
 		shgd->ed_context = (void*)ed_open(shp);
 		error_info.exit = sh_exit;
 		error_info.id = path_basename(argv[0]);
@@ -1423,9 +1381,6 @@ Shell_t *sh_init(register int argc,register char *argv[], Shinit_f userinit)
 	}
 #endif
 	nv_putval(IFSNOD,(char*)e_sptbnl,NV_RDONLY);
-#if SHOPT_FS_3D
-	nv_stack(VPATHNOD, &VPATH_init);
-#endif /* SHOPT_FS_3D */
 	astconfdisc(newconf);
 #if SHOPT_TIMEOUT
 	shp->st.tmout = SHOPT_TIMEOUT;

src/cmd/ksh93/sh/io.c

@@ -1352,12 +1352,7 @@ int	sh_redirect(Shell_t *shp,struct ionod *iop, int flag)
 						struct stat sb;
 						if(stat(fname,&sb)>=0)
 						{
-#if SHOPT_FS_3D
-							if(S_ISREG(sb.st_mode)&&
-						                (!shp->gd->lim.fs3d || iview(&sb)==0))
-#else
 							if(S_ISREG(sb.st_mode))
-#endif /* SHOPT_FS_3D */
 							{
 								errno = EEXIST;
 								errormsg(SH_DICT,ERROR_system(1),e_exists,fname);

src/cmd/ksh93/sh/jobs.c

@@ -1905,16 +1905,6 @@ static void job_free(register int n)
 static char *job_sigmsg(int sig)
 {
 	static char signo[40];
-#ifdef apollo
-	/*
-	 * This code handles the formatting for the apollo specific signal
-	 * SIGAPOLLO. 
-	 */
-	extern char *apollo_error(void);
-	
-	if ( sig == SIGAPOLLO )
-		return( apollo_error() );
-#endif /* apollo */
 	if(sig<=shgd->sigmax && shgd->sigmsg[sig])
 		return(shgd->sigmsg[sig]);
 #if defined(SIGRTMIN) && defined(SIGRTMAX)

src/cmd/ksh93/sh/path.c

@@ -1181,15 +1181,6 @@ pid_t path_spawn(Shell_t *shp,const char *opath,register char **argv, char **env
 retry:
 	switch(shp->path_err = errno)
 	{
-#ifdef apollo
-	    /* 
-  	     * On apollo's execve will fail with eacces when
-	     * file has execute but not read permissions. So,
-	     * for now we will pretend that EACCES and ENOEXEC
- 	     * mean the same thing.
- 	     */
-	    case EACCES:
-#endif /* apollo */
 	    case ENOEXEC:
 #if SHOPT_SUID_EXEC
 	    case EPERM:
@@ -1213,7 +1204,6 @@ retry:
 #endif
 		}
 		exscript(shp,path,argv,envp);
-#ifndef apollo
 	    case EACCES:
 	    {
 		struct stat statb;
@@ -1228,7 +1218,6 @@ retry:
 		}
 	    }
 		/* FALL THROUGH */
-#endif /* !apollo */
 #ifdef ENAMETOOLONG
 	    case ENAMETOOLONG:
 #endif /* ENAMETOOLONG */