sh_exec(), sh_ntfork(): rm leftover pre-fork(2) code (re: 7b0e077)

I had missed something while removing the legacy code for ancient
systems without fork(2). The SH_NTFORK bit flag was only ever
passed to sh_exec() from the version of sh_ntfork() that was
compiled on systems without fork(2). With that call removed, this
flag is now completely unused. This commit removes the flag and the
code that is never executed since that flag is never passed.

src/cmd/ksh93/sh/xec.c

@@ -56,17 +56,16 @@
 #   include <sys/resource.h>
 #endif
 
-#if SHOPT_SPAWN && _lib_posix_spawn > 1 && _lib_posix_spawn_file_actions_addtcsetpgrp_np
+#undef _use_ntfork_tcpgrp
+#if defined(JOBS) && SHOPT_SPAWN && _lib_posix_spawn > 1 && _lib_posix_spawn_file_actions_addtcsetpgrp_np
 #define _use_ntfork_tcpgrp 1
 #endif
 
-#define SH_NTFORK	SH_TIMING
-
 #if _lib_nice
     extern int	nice(int);
 #endif /* _lib_nice */
 #if SHOPT_SPAWN
-    static pid_t sh_ntfork(const Shnode_t*,char*[],int*,int);
+    static pid_t sh_ntfork(const Shnode_t*,char*[],int*);
 #endif /* SHOPT_SPAWN */
 
 static void	sh_funct(Namval_t*, int, char*[], struct argnod*,int);
@@ -935,11 +934,6 @@ int sh_exec(register const Shnode_t *t, int flags)
 		int 		execflg = (type&sh_state(SH_NOFORK));
 		int 		execflg2 = (type&sh_state(SH_FORKED));
 		int 		mainloop = (type&sh_state(SH_INTERACTIVE));
-#if SHOPT_SPAWN
-		int		ntflag = (type&sh_state(SH_NTFORK));
-#else
-		int		ntflag = 0;
-#endif
 		int		topfd = sh.topfd;
 		char 		*sav=stkfreeze(stkp,0);
 		char		*cp=0, **com=0, *comn;
@@ -1516,8 +1510,7 @@ int sh_exec(register const Shnode_t *t, int flags)
 						sh_subfork();
 				}
 			}
-			no_fork = !ntflag
-			&& !(type&(FAMP|FPOU))
+			no_fork = !(type&(FAMP|FPOU))
 			&& !sh.subshell
 			&& !(sh.st.trapcom[SIGINT] && *sh.st.trapcom[SIGINT])
 			&& !sh.st.trapcom[0]
@@ -1557,7 +1550,7 @@ int sh_exec(register const Shnode_t *t, int flags)
 				if(com && !job.jobcontrol)
 #endif /* _use_ntfork_tcpgrp */
 				{
-					parent = sh_ntfork(t,com,&jobid,ntflag);
+					parent = sh_ntfork(t,com,&jobid);
 					if(parent<0)
 					{
 						if(sh.topfd > topfd)
@@ -3412,35 +3405,24 @@ static void sigreset(int mode)
  * Incompatible with job control on interactive shells (job.jobcontrol) if
  * the system does not support posix_spawn_file_actions_addtcsetpgrp_np().
  */
-static pid_t sh_ntfork(const Shnode_t *t,char *argv[],int *jobid,int flag)
+static pid_t sh_ntfork(const Shnode_t *t,char *argv[],int *jobid)
 {
 	static pid_t	spawnpid;
-	static int	savetype;
 	struct checkpt	*buffp = (struct checkpt*)stkalloc(sh.stk,sizeof(struct checkpt));
-	int		otype=0, jmpval,jobfork=0;
+	int		jmpval,jobfork=0;
 	volatile int	scope=0, sigwasset=0;
 	char		**arge, *path;
 	volatile pid_t	grp = 0;
 	Pathcomp_t	*pp;
 #if _use_ntfork_tcpgrp
 	volatile int	jobwasset=0;
 #endif /* _use_ntfork_tcpgrp */
-	if(flag)
-	{
-		otype = savetype;
-		savetype=0;
-	}
 	sh_pushcontext(buffp,SH_JMPCMD);
 	errorpush(&buffp->err,ERROR_SILENT);
 	job_lock();		/* errormsg will unlock */
 	jmpval = sigsetjmp(buffp->buff,0);
 	if(jmpval == 0)
 	{
-		if((otype&FINT) && !sh_isstate(SH_MONITOR))
-		{
-			signal(SIGQUIT,SIG_IGN);
-			signal(SIGINT,SIG_IGN);
-		}
 		spawnpid = -1;
 		if(t->com.comio)
 			sh_redirect(t->com.comio,0);
@@ -3498,19 +3480,15 @@ static pid_t sh_ntfork(const Shnode_t *t,char *argv[],int *jobid,int flag)
 			jobwasset++;
 		}
 #endif /* _use_ntfork_tcpgrp */
-#ifdef JOBS
 #if _use_ntfork_tcpgrp
-		if(sh_isstate(SH_MONITOR) && (job.jobcontrol || (otype&FAMP)))
-#else
-		if(sh_isstate(SH_MONITOR) && (otype&FAMP))
-#endif /* _use_ntfork_tcpgrp */
+		if(sh_isstate(SH_MONITOR) && job.jobcontrol)
 		{
-			if((otype&FAMP) || job.curpgid==0)
+			if(job.curpgid==0)
 				grp = 1;
 			else
 				grp = job.curpgid;
 		}
-#endif /* JOBS */
+#endif /* _use_ntfork_tcpgrp */
 
 		sfsync(NIL(Sfio_t*));
 		sigreset(0);	/* set signals to ignore */
@@ -3605,14 +3583,12 @@ static pid_t sh_ntfork(const Shnode_t *t,char *argv[],int *jobid,int flag)
 		siglongjmp(*sh.jmplist,jmpval);
 	if(spawnpid>0)
 	{
-		_sh_fork(spawnpid,otype,jobid);
+		_sh_fork(spawnpid,0,jobid);
 		job_fork(spawnpid);
 #ifdef JOBS
 		if(grp==1)
 			job.curpgid = spawnpid;
 #endif /* JOBS */
-		if(otype)
-			return(0);
 	}
 	return(spawnpid);
 }