rm redundant getpid(2) syscalls (re: 9de6521)

Now that we have ${.sh.pid} a.k.a. shgd->current_pid, which is
updated using getpid() whenever forking a new process, there is no
need for anything else to ever call getpid(); we can use the stored
value instead. There were a lot of these syscalls kicking around,
some of them in performance-sensitive places.

The following lists only changes *other* than changing getpid() to
shgd->currentpid.

src/cmd/ksh93/include/defs.h:
- Comments: clarify what shgd->{pid,ppid,current_pid} are for.

src/cmd/ksh93/sh/main.c,
src/cmd/ksh93/sh/init.c:
- On reinit for a new script, update shgd->{pid,ppid,current_pid}
  in the sh_reinit() function itself instead of calling sh_reinit()
  from sh_main() and then updating those immediately after that
  call. It just makes more sense this way. Nothing else ever calls
  sh_reinit() so there are no side effects.

src/cmd/ksh93/sh/xec.c: _sh_fork():
- Update shgd->current_pid in the child early, so that the rest of
  the function can use it instead of calling getpid() again.
- Remove reassignment of SH_PIDNOD->nvalue.lp value pointer to
  shgd->current_pid (which makes ${.sh.pid} work in the shell).
  It's constant and was already set on init.

src/cmd/ksh93/edit/history.c

@@ -363,7 +363,7 @@ int  sh_histinit(void *sh_context)
 	if(hist_clean(fd) && hist_start>1 && hsize > HIST_MAX)
 	{
 #ifdef DEBUG
-		sfprintf(sfstderr,"%d: hist_trim hsize=%d\n",getpid(),hsize);
+		sfprintf(sfstderr,"%d: hist_trim hsize=%d\n",shgd->current_pid,hsize);
 		sfsync(sfstderr);
 #endif /* DEBUG */
 		hp = hist_trim(hp,(int)hp->histind-maxlines);

src/cmd/ksh93/include/defs.h

@@ -134,9 +134,9 @@ struct shared
 	uid_t		euserid;
 	gid_t		groupid;
 	gid_t		egroupid;
-	pid_t		pid;
-	pid_t		ppid;
-	pid_t		current_pid;  /* pid of the current ksh instance */
+	pid_t		pid;		/* $$, the main shell's PID (invariable) */
+	pid_t		ppid;		/* $PPID, the main shell's parent's PID */
+	pid_t		current_pid;	/* ${.sh.pid}, PID of current ksh process (updates when subshell forks) */
 	unsigned char	sigruntime[2];
 	Namval_t	*bltin_nodes;
 	Namval_t	*bltin_cmds;

src/cmd/ksh93/sh/fault.c

@@ -660,7 +660,7 @@ void sh_done(void *ptr, register int sig)
 		}
 		signal(sig,SIG_DFL);
 		sigrelease(sig);
-		kill(getpid(),sig);
+		kill(shgd->current_pid,sig);
 		pause();
 	}
 #if SHOPT_KIA

src/cmd/ksh93/sh/init.c

@@ -1574,6 +1574,9 @@ int sh_reinit(char *argv[])
 	shp->inpipe = shp->outpipe = 0;
 	job_clear();
 	job.in_critical = 0;
+	/* update ${.sh.pid}, $$, $PPID */
+	shgd->current_pid = shgd->pid = getpid();
+	shgd->ppid = getppid();
 	return(1);
 }
 

src/cmd/ksh93/sh/io.c

@@ -1058,7 +1058,7 @@ static char *io_usename(char *name, int *perm, int fno, int mode)
 		stakseek(0);
 	}
 	stakputc('.');
-	sfprintf(stkstd,"%<#d_%d{;.tmp",getpid(),fno);
+	sfprintf(stkstd,"%<#d_%d{;.tmp",shgd->current_pid,fno);
 	tname = stakfreeze(1);
 	switch(mode)
 	{
@@ -1410,7 +1410,7 @@ int	sh_redirect(Shell_t *shp,struct ionod *iop, int flag)
 			}
 			if(!np)
 			{
-				if(flag==0 || tname || (flag==1 && fn==1 && (shp->fdstatus[fn]&IONOSEEK) && shp->outpipepid && shp->outpipepid==getpid()))
+				if(flag==0 || tname || (flag==1 && fn==1 && (shp->fdstatus[fn]&IONOSEEK) && shp->outpipepid == shgd->current_pid))
 				{
 					if(fd==fn)
 					{
@@ -2170,7 +2170,7 @@ static void	sftrack(Sfio_t* sp, int flag, void* data)
 #ifdef DEBUG
 	if(flag==SF_READ || flag==SF_WRITE)
 	{
-		char *z = fmtbase((long)getpid(),0,0);
+		char *z = fmtbase((long)shgd->current_pid,0,0);
 		write(ERRIO,z,strlen(z));
 		write(ERRIO,": ",2);
 		write(ERRIO,"attempt to ",11);

src/cmd/ksh93/sh/jobs.c

@@ -276,7 +276,7 @@ int job_reap(register int sig)
 			abort();
 	}
 #ifdef DEBUG
-	if(sfprintf(sfstderr,"ksh: job line %4d: reap pid=%d critical=%d signal=%d\n",__LINE__,getpid(),job.in_critical,sig) <=0)
+	if(sfprintf(sfstderr,"ksh: job line %4d: reap pid=%d critical=%d signal=%d\n",__LINE__,shgd->current_pid,job.in_critical,sig) <=0)
 		write(2,"waitsafe\n",9);
 	sfsync(sfstderr);
 #endif /* DEBUG */
@@ -325,7 +325,7 @@ int job_reap(register int sig)
 		if(!(pw=job_bypid(pid)))
 		{
 #ifdef DEBUG
-			sfprintf(sfstderr,"ksh: job line %4d: reap pid=%d critical=%d unknown job pid=%d pw=%x\n",__LINE__,getpid(),job.in_critical,pid,pw);
+			sfprintf(sfstderr,"ksh: job line %4d: reap pid=%d critical=%d unknown job pid=%d pw=%x\n",__LINE__,shgd->current_pid,job.in_critical,pid,pw);
 #endif /* DEBUG */
 			if (WIFCONTINUED(wstat) && wcontinued)
 				continue;
@@ -355,7 +355,7 @@ int job_reap(register int sig)
 			pw->p_flag |= (P_NOTIFY|P_SIGNALLED|P_STOPPED);
 			pw->p_exit = WSTOPSIG(wstat);
 			if(pw->p_pgrp && pw->p_pgrp==job.curpgid && sh_isstate(SH_STOPOK))
-				kill(getpid(),pw->p_exit); 
+				kill(shgd->current_pid,pw->p_exit);
 			if(px)
 			{
 				/* move to top of job list */
@@ -393,7 +393,7 @@ int job_reap(register int sig)
 				{
 					pw->p_flag &= ~P_NOTIFY;
 					sh_offstate(SH_STOPOK);
-					kill(getpid(),SIGINT); 
+					kill(shgd->current_pid,SIGINT);
 					sh_onstate(SH_STOPOK);
 				}
 			}
@@ -430,7 +430,7 @@ int job_reap(register int sig)
 				jp->exitval |= SH_EXITSIG;
 		}
 #ifdef DEBUG
-		sfprintf(sfstderr,"ksh: job line %4d: reap pid=%d critical=%d job %d with pid %d flags=%o complete with status=%x exit=%d\n",__LINE__,getpid(),job.in_critical,pw->p_job,pid,pw->p_flag,wstat,pw->p_exit);
+		sfprintf(sfstderr,"ksh: job line %4d: reap pid=%d critical=%d job %d with pid %d flags=%o complete with status=%x exit=%d\n",__LINE__,shgd->current_pid,job.in_critical,pw->p_job,pid,pw->p_flag,wstat,pw->p_exit);
 		sfsync(sfstderr);
 #endif /* DEBUG*/
 		/* only top-level process in job should have notify set */
@@ -645,7 +645,7 @@ int job_close(Shell_t* shp)
 		return(0);
 	else if(!possible && (!sh_isstate(SH_MONITOR) || sh_isstate(SH_FORKED)))
 		return(0);
-	else if(getpid() != job.mypid)
+	else if(shgd->current_pid != job.mypid)
 		return(0);
 	job_lock();
 	if(!tty_check(0))
@@ -1238,7 +1238,7 @@ int job_post(Shell_t *shp,pid_t pid, pid_t join)
 		pw->p_fgrp = 0;
 	pw->p_pgrp = pw->p_fgrp;
 #ifdef DEBUG
-	sfprintf(sfstderr,"ksh: job line %4d: post pid=%d critical=%d job=%d pid=%d pgid=%d savesig=%d join=%d\n",__LINE__,getpid(),job.in_critical,pw->p_job,
+	sfprintf(sfstderr,"ksh: job line %4d: post pid=%d critical=%d job=%d pid=%d pgid=%d savesig=%d join=%d\n",__LINE__,shgd->current_pid,job.in_critical,pw->p_job,
 		pw->p_pid,pw->p_pgrp,job.savesig,join);
 	sfsync(sfstderr);
 #endif /* DEBUG */
@@ -1390,9 +1390,9 @@ int	job_wait(register pid_t pid)
 	}
 	pwfg = pw;
 #ifdef DEBUG
-	sfprintf(sfstderr,"ksh: job line %4d: wait pid=%d critical=%d job=%d pid=%d\n",__LINE__,getpid(),job.in_critical,jobid,pid);
+	sfprintf(sfstderr,"ksh: job line %4d: wait pid=%d critical=%d job=%d pid=%d\n",__LINE__,shgd->current_pid,job.in_critical,jobid,pid);
 	if(pw)
-		sfprintf(sfstderr,"ksh: job line %4d: wait pid=%d critical=%d flags=%o\n",__LINE__,getpid(),job.in_critical,pw->p_flag);
+		sfprintf(sfstderr,"ksh: job line %4d: wait pid=%d critical=%d flags=%o\n",__LINE__,shgd->current_pid,job.in_critical,pw->p_flag);
 #endif /* DEBUG*/
 	errno = 0;
 	if(shp->coutpipe>=0 && lastpid && shp->cpid==lastpid)
@@ -1498,12 +1498,12 @@ int	job_wait(register pid_t pid)
 		job_reset(pw);
 		/* propagate keyboard interrupts to parent */
 		if((pw->p_flag&P_SIGNALLED) && pw->p_exit==SIGINT && !(shp->sigflag[SIGINT]&SH_SIGOFF))
-			kill(getpid(),SIGINT); 
+			kill(shgd->current_pid,SIGINT);
 #ifdef SIGTSTP
 		else if((pw->p_flag&P_STOPPED) && pw->p_exit==SIGTSTP)
 		{
 			job.parent = 0;
-			kill(getpid(),SIGTSTP); 
+			kill(shgd->current_pid,SIGTSTP);
 		}
 #endif /* SIGTSTP */
 	}
@@ -1647,7 +1647,7 @@ static struct process *job_unpost(register struct process *pwtop,int notify)
 	register struct process *pw;
 	/* make sure all processes are done */
 #ifdef DEBUG
-	sfprintf(sfstderr,"ksh: job line %4d: drop pid=%d critical=%d pid=%d env=%u\n",__LINE__,getpid(),job.in_critical,pwtop->p_pid,pwtop->p_env);
+	sfprintf(sfstderr,"ksh: job line %4d: drop pid=%d critical=%d pid=%d env=%u\n",__LINE__,shgd->current_pid,job.in_critical,pwtop->p_pid,pwtop->p_env);
 	sfsync(sfstderr);
 #endif /* DEBUG */
 	pwtop = pw = job_byjid((int)pwtop->p_job);
@@ -1686,7 +1686,7 @@ static struct process *job_unpost(register struct process *pwtop,int notify)
 	}
 	pwtop->p_pid = 0;
 #ifdef DEBUG
-	sfprintf(sfstderr,"ksh: job line %4d: free pid=%d critical=%d job=%d\n",__LINE__,getpid(),job.in_critical,pwtop->p_job);
+	sfprintf(sfstderr,"ksh: job line %4d: free pid=%d critical=%d job=%d\n",__LINE__,shgd->current_pid,job.in_critical,pwtop->p_job);
 	sfsync(sfstderr);
 #endif /* DEBUG */
 	job_free((int)pwtop->p_job);
@@ -1889,7 +1889,7 @@ int sh_waitsafe(void)
 void job_fork(pid_t parent)
 {
 #ifdef DEBUG
-	sfprintf(sfstderr,"ksh: job line %4d: fork pid=%d critical=%d parent=%d\n",__LINE__,getpid(),job.in_critical,parent);
+	sfprintf(sfstderr,"ksh: job line %4d: fork pid=%d critical=%d parent=%d\n",__LINE__,shgd->current_pid,job.in_critical,parent);
 #endif /* DEBUG */
 	switch (parent)
 	{

src/cmd/ksh93/sh/lex.c

@@ -306,7 +306,7 @@ int sh_lex(Lex_t *lp)
 		if(flag&ARG_QUOTED)
 			quoted = "quoted:";
 	}
-	sfprintf(sfstderr,"%d: line %d: %o:%s%s%s%s %s\n",getpid(),shp->inlineno,tok,quoted,
+	sfprintf(sfstderr,"%d: line %d: %o:%s%s%s%s %s\n",shgd->current_pid,shp->inlineno,tok,quoted,
 		macro, split, expand, fmttoken(lp,tok,tokstr));
 	return(tok);
 }

src/cmd/ksh93/sh/main.c

@@ -146,8 +146,6 @@ int sh_main(int ac, char *av[], Shinit_f userinit)
 	{
 		/* 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;
@@ -518,7 +516,7 @@ static void	exfile(register Shell_t *shp, register Sfio_t *iop,register int fno)
 			{
 				buff.mode = SH_JMPERREXIT;
 #ifdef DEBUG
-				errormsg(SH_DICT,ERROR_warn(0),"%d: mode changed to JMP_EXIT",getpid());
+				errormsg(SH_DICT,ERROR_warn(0),"%d: mode changed to JMP_EXIT",shgd->current_pid);
 #endif
 			}
 		}

src/cmd/ksh93/sh/path.c

@@ -1077,7 +1077,7 @@ pid_t path_spawn(Shell_t *shp,const char *opath,register char **argv, char **env
 #if _lib_readlink
 	/* save original pathname */
 	stakseek(PATH_OFFSET);
-	pidsize = sfprintf(stkstd,"*%d*",spawn?getpid():getppid());
+	pidsize = sfprintf(stkstd,"*%d*",spawn?shgd->current_pid:getppid());
 	stakputs(opath);
 	opath = stakfreeze(1)+PATH_OFFSET+pidsize;
 	/* only use tracked alias if we're not searching default path */
@@ -1304,7 +1304,7 @@ static void exscript(Shell_t *shp,register char *path,register char *argv[],char
 		}
 		if((euserid=geteuid()) != shp->gd->userid)
 		{
-			strncpy(name+9,fmtbase((long)getpid(),10,0),sizeof(name)-10);
+			strncpy(name+9,fmtbase((long)shgd->current_pid,10,0),sizeof(name)-10);
 			/* create a suid open file with owner equal effective uid */
 			if((n=open(name,O_CREAT|O_TRUNC|O_WRONLY,S_ISUID|S_IXUSR)) < 0)
 				goto fail;

src/cmd/ksh93/sh/subshell.c

@@ -791,7 +791,7 @@ Sfio_t *sh_subshell(Shell_t *shp,Shnode_t *t, volatile int flags, int comsub)
 			sp->prev->sig = sp->sig;
 		else
 		{
-			kill(getpid(),sp->sig);
+			kill(shgd->current_pid,sp->sig);
 			sh_chktrap(shp);
 		}
 	}
@@ -800,7 +800,7 @@ Sfio_t *sh_subshell(Shell_t *shp,Shnode_t *t, volatile int flags, int comsub)
 	nsig = shp->savesig;
 	shp->savesig = 0;
 	if(nsig>0)
-		kill(getpid(),nsig);
+		kill(shgd->current_pid,nsig);
 	if(sp->subpid)
 	{
 		job_wait(sp->subpid);
@@ -816,7 +816,7 @@ Sfio_t *sh_subshell(Shell_t *shp,Shnode_t *t, volatile int flags, int comsub)
 	{
 		int sig = shp->exitval&SH_EXITMASK;
 		if(sig==SIGINT || sig== SIGQUIT)
-			kill(getpid(),sig);
+			kill(shgd->current_pid,sig);
 	}
 	if(duped)
 	{
@@ -825,9 +825,9 @@ Sfio_t *sh_subshell(Shell_t *shp,Shnode_t *t, volatile int flags, int comsub)
 		errormsg(SH_DICT,ERROR_system(1),e_redirect);
 	}
 	if(shp->ignsig)
-		kill(getpid(),shp->ignsig);
+		kill(shgd->current_pid,shp->ignsig);
 	if(jmpval==SH_JMPSUB && shp->lastsig)
-		kill(getpid(),shp->lastsig);
+		kill(shgd->current_pid,shp->lastsig);
 	if(jmpval && shp->toomany)
 		siglongjmp(*shp->jmplist,jmpval);
 	return(iop);

src/cmd/ksh93/sh/suid_exec.c

@@ -482,7 +482,7 @@ static void setids(int mode,uid_t owner,gid_t group)
 static void maketemp(char *template)
 {
 	register char *cp = template;
-	register pid_t n = getpid();
+	register pid_t n = shgd->current_pid;
 	/* skip to end of string */
 	while(*++cp);
 	/* convert process id to string */

src/cmd/ksh93/sh/timers.c

@@ -94,7 +94,7 @@ static void sigalrm(int sig)
 	if(time_state&SIGALRM_CALL)
 		time_state &= ~SIGALRM_CALL;
 	else if(alarm(0))
-		kill(getpid(),SIGALRM|SH_TRAP);
+		kill(shgd->current_pid,SIGALRM|SH_TRAP);
 	if(time_state)
 	{
 		if(time_state&IN_ADDTIMEOUT)

src/cmd/ksh93/sh/xec.c

@@ -1636,7 +1636,7 @@ int sh_exec(register const Shnode_t *t, int flags)
 					{
 						shp->trapnote &= ~SH_SIGIGNORE;
 						if(shp->exitval == (SH_EXITSIG|SIGINT))
-							kill(getpid(),SIGINT);
+							kill(shgd->current_pid,SIGINT);
 					}
 				}
 				if(type&FAMP)
@@ -2887,8 +2887,9 @@ pid_t _sh_fork(Shell_t *shp,register pid_t parent,int flags,int *jobid)
 #if !_std_malloc
 	vmtrace(-1);
 #endif
-	shp->outpipepid = ((flags&FPOU)?getpid():0);
 	/* This is the child process */
+	shgd->current_pid = getpid();  /* ${.sh.pid} */
+	shp->outpipepid = ((flags&FPOU)?shgd->current_pid:0);
 	if(shp->trapnote&SH_SIGTERM)
 		sh_exit(SH_EXITSIG|SIGTERM);
 	shp->gd->nforks=0;
@@ -2898,7 +2899,7 @@ pid_t _sh_fork(Shell_t *shp,register pid_t parent,int flags,int *jobid)
 		sh_offstate(SH_MONITOR);
 	if(sh_isstate(SH_MONITOR))
 	{
-		parent = getpid();
+		parent = shgd->current_pid;
 		if(postid==0)
 			job.curpgid = parent;
 		while(setpgid(0,job.curpgid)<0 && job.curpgid!=parent)
@@ -2925,9 +2926,6 @@ pid_t _sh_fork(Shell_t *shp,register pid_t parent,int flags,int *jobid)
 	sh_onstate(SH_NOLOG);
 	if (shp->fn_reset)
 		shp->fn_depth = shp->fn_reset = 0;
-	/* Set ${.sh.pid} to the child process ID */
-	shp->gd->current_pid = getpid();
-	SH_PIDNOD->nvalue.lp = &shp->gd->current_pid;
 #if SHOPT_ACCT
 	sh_accsusp();
 #endif	/* SHOPT_ACCT */
@@ -2944,7 +2942,7 @@ pid_t _sh_fork(Shell_t *shp,register pid_t parent,int flags,int *jobid)
 	sig = shp->savesig;
 	shp->savesig = 0;
 	if(sig>0)
-		kill(getpid(),sig);
+		kill(shgd->current_pid,sig);
 	sh_sigcheck(shp);
 	usepipe=0;
 	return(0);
@@ -2965,7 +2963,7 @@ pid_t sh_fork(Shell_t *shp,int flags, int *jobid)
 	sig = shp->savesig;
 	shp->savesig = 0;
 	if(sig>0)
-		kill(getpid(),sig);
+		kill(shgd->current_pid,sig);
 	job_fork(parent);
 	return(parent);
 }
@@ -3177,7 +3175,7 @@ int sh_funscope(int argn, char *argv[],int(*fun)(void*),void *arg,int execflg)
 	if(jmpval)
 		r=shp->exitval;
 	if(r>SH_EXITSIG && ((r&SH_EXITMASK)==SIGINT || ((r&SH_EXITMASK)==SIGQUIT)))
-		kill(getpid(),r&SH_EXITMASK);
+		kill(shgd->current_pid,r&SH_EXITMASK);
 	if(jmpval > SH_JMPFUN)
 	{
 		sh_chktrap(shp);