[unix-history] / usr / src / old / sh / service.c

#ifndef lint
static char sccsid[] = "@(#)service.c	4.2 %G%";
#endif

#
/*
 * UNIX shell
 *
 * S. R. Bourne
 * Bell Telephone Laboratories
 *
 */

#include	"defs.h"


PROC VOID	gsort();

#define ARGMK	01

INT		errno;
STRING		sysmsg[];

/* fault handling */
#define ENOMEM	12
#define ENOEXEC 8
#define E2BIG	7
#define ENOENT	2
#define ETXTBSY 26


/* service routines for `execute' */

VOID	initio(iop)
	IOPTR		iop;
{
	REG STRING	ion;
	REG INT		iof, fd;

	IF iop
	THEN	iof=iop->iofile;
		ion=mactrim(iop->ioname);
		IF *ion ANDF (flags&noexec)==0
		THEN	IF iof&IODOC
			THEN	subst(chkopen(ion),(fd=tmpfil()));
				close(fd); fd=chkopen(tmpout); unlink(tmpout);
			ELIF iof&IOMOV
			THEN	IF eq(minus,ion)
				THEN	fd = -1;
					close(iof&IOUFD);
				ELIF (fd=stoi(ion))>=USERIO
				THEN	failed(ion,badfile);
				ELSE	fd=dup(fd);
				FI
			ELIF (iof&IOPUT)==0
			THEN	fd=chkopen(ion);
			ELIF flags&rshflg
			THEN	failed(ion,restricted);
			ELIF iof&IOAPP ANDF (fd=open(ion,1))>=0
			THEN	lseek(fd, 0L, 2);
			ELSE	fd=create(ion);
			FI
			IF fd>=0
			THEN	rename(fd,iof&IOUFD);
			FI
		FI
		initio(iop->ionxt);
	FI
}

STRING	getpath(s)
	STRING		s;
{
	REG STRING	path;
	IF any('/',s)
	THEN	IF flags&rshflg
		THEN	failed(s, restricted);
		ELSE	return(nullstr);
		FI
	ELIF (path = pathnod.namval)==0
	THEN	return(defpath);
	ELSE	return(cpystak(path));
	FI
}

INT	pathopen(path, name)
	REG STRING	path, name;
{
	REG UFD		f;

	REP path=catpath(path,name);
	PER (f=open(curstak(),0))<0 ANDF path DONE
	return(f);
}

STRING	catpath(path,name)
	REG STRING	path;
	STRING		name;
{
	/* leaves result on top of stack */
	REG STRING	scanp = path,
			argp = locstak();

	WHILE *scanp ANDF *scanp!=COLON DO *argp++ = *scanp++ OD
	IF scanp!=path THEN *argp++='/' FI
	IF *scanp==COLON THEN scanp++ FI
	path=(*scanp ? scanp : 0); scanp=name;
	WHILE (*argp++ = *scanp++) DONE
	return(path);
}

LOCAL STRING	xecmsg;
LOCAL STRING	*xecenv;

VOID	execa(at)
	STRING		at[];
{
	REG STRING	path;
	REG STRING	*t = at;

	IF (flags&noexec)==0
	THEN	xecmsg=notfound; path=getpath(*t);
		namscan(exname);
		xecenv=setenv();
		WHILE path=execs(path,t) DONE
		failed(*t,xecmsg);
	FI
}

LOCAL STRING	execs(ap,t)
	STRING		ap;
	REG STRING	t[];
{
	REG STRING	p, prefix;

	prefix=catpath(ap,t[0]);
	trim(p=curstak());

	sigchk();
	execve(p, &t[0] ,xecenv);
	SWITCH errno IN

	    case ENOEXEC:
		flags=0;
		comdiv=0; ioset=0;
		clearup(); /* remove open files and for loop junk */
		IF input THEN close(input) FI
		close(output); output=2;
		input=chkopen(p);

		/* band aid to get csh... 2/26/79 */
		{
			char c;
			if (!isatty(input)) {
				read(input, &c, 1);
				if (c == '#')
					gocsh(t, p, xecenv);
				lseek(input, (long) 0, 0);
			}
		}

		/* set up new args */
		setargs(t);
		longjmp(subshell,1);

	    case ENOMEM:
		failed(p,toobig);

	    case E2BIG:
		failed(p,arglist);

	    case ETXTBSY:
		failed(p,txtbsy);

	    default:
		xecmsg=badexec;
	    case ENOENT:
		return(prefix);
	ENDSW
}

gocsh(t, cp, xecenv)
	register char **t, *cp, **xecenv;
{
	char **newt[1000];
	register char **p;
	register int i;

	for (i = 0; t[i]; i++)
		newt[i+1] = t[i];
	newt[i+1] = 0;
	newt[0] = "/bin/csh";
	newt[1] = cp;
	execve("/bin/csh", newt, xecenv);
}

/* for processes to be waited for */
#define MAXP 20
LOCAL INT	pwlist[MAXP];
LOCAL INT	pwc;

postclr()
{
	REG INT		*pw = pwlist;

	WHILE pw <= &pwlist[pwc]
	DO *pw++ = 0 OD
	pwc=0;
}

VOID	post(pcsid)
	INT		pcsid;
{
	REG INT		*pw = pwlist;

	IF pcsid
	THEN	WHILE *pw DO pw++ OD
		IF pwc >= MAXP-1
		THEN	pw--;
		ELSE	pwc++;
		FI
		*pw = pcsid;
	FI
}

VOID	await(i)
	INT		i;
{
	INT		rc=0, wx=0;
	INT		w;
	INT		ipwc = pwc;

	post(i);
	WHILE pwc
	DO	REG INT		p;
		REG INT		sig;
		INT		w_hi;

		BEGIN
		   REG INT	*pw=pwlist;
		   p=wait(&w);
		   WHILE pw <= &pwlist[ipwc]
		   DO IF *pw==p
		      THEN *pw=0; pwc--;
		      ELSE pw++;
		      FI
		   OD
		END

		IF p == -1 THEN continue FI

		w_hi = (w>>8)&LOBYTE;

		IF sig = w&0177
		THEN	IF sig == 0177	/* ptrace! return */
			THEN	prs("ptrace: ");
				sig = w_hi;
			FI
			IF sysmsg[sig]
			THEN	IF i!=p ORF (flags&prompt)==0 THEN prp(); prn(p); blank() FI
				prs(sysmsg[sig]);
				IF w&0200 THEN prs(coredump) FI
			FI
			newline();
		FI

		IF rc==0
		THEN	rc = (sig ? sig|SIGFLG : w_hi);
		FI
		wx |= w;
	OD

	IF wx ANDF flags&errflg
	THEN	exitsh(rc);
	FI
	exitval=rc; exitset();
}

BOOL		nosubst;

trim(at)
	STRING		at;
{
	REG STRING	p;
	REG CHAR	c;
	REG CHAR	q=0;

	IF p=at
	THEN	WHILE c = *p
		DO *p++=c&STRIP; q |= c OD
	FI
	nosubst=q&QUOTE;
}

STRING	mactrim(s)
	STRING		s;
{
	REG STRING	t=macro(s);
	trim(t);
	return(t);
}

STRING	*scan(argn)
	INT		argn;
{
	REG ARGPTR	argp = Rcheat(gchain)&~ARGMK;
	REG STRING	*comargn, *comargm;

	comargn=getstak(BYTESPERWORD*argn+BYTESPERWORD); comargm = comargn += argn; *comargn = ENDARGS;

	WHILE argp
	DO	*--comargn = argp->argval;
		IF argp = argp->argnxt
		THEN trim(*comargn);
		FI
		IF argp==0 ORF Rcheat(argp)&ARGMK
		THEN	gsort(comargn,comargm);
			comargm = comargn;
		FI
		/* Lcheat(argp) &= ~ARGMK; */
		argp = Rcheat(argp)&~ARGMK;
	OD
	return(comargn);
}

LOCAL VOID	gsort(from,to)
	STRING		from[], to[];
{
	INT		k, m, n;
	REG INT		i, j;

	IF (n=to-from)<=1 THEN return FI

	FOR j=1; j<=n; j*=2 DONE

	FOR m=2*j-1; m/=2;
	DO  k=n-m;
	    FOR j=0; j<k; j++
	    DO	FOR i=j; i>=0; i-=m
		DO  REG STRING *fromi; fromi = &from[i];
		    IF cf(fromi[m],fromi[0])>0
		    THEN break;
		    ELSE STRING s; s=fromi[m]; fromi[m]=fromi[0]; fromi[0]=s;
		    FI
		OD
	    OD
	OD
}

/* Argument list generation */

INT	getarg(ac)
	COMPTR		ac;
{
	REG ARGPTR	argp;
	REG INT		count=0;
	REG COMPTR	c;

	IF c=ac
	THEN	argp=c->comarg;
		WHILE argp
		DO	count += split(macro(argp->argval));
			argp=argp->argnxt;
		OD
	FI
	return(count);
}

LOCAL INT	split(s)
	REG STRING	s;
{
	REG STRING	argp;
	REG INT		c;
	INT		count=0;

	LOOP	sigchk(); argp=locstak()+BYTESPERWORD;
		WHILE (c = *s++, !any(c,ifsnod.namval) && c)
		DO *argp++ = c OD
		IF argp==staktop+BYTESPERWORD
		THEN	IF c
			THEN	continue;
			ELSE	return(count);
			FI
		ELIF c==0
		THEN	s--;
		FI
		IF c=expand((argp=endstak(argp))->argval,0)
		THEN	count += c;
		ELSE	/* assign(&fngnod, argp->argval); */
			makearg(argp); count++;
		FI
		Lcheat(gchain) |= ARGMK;
	POOL
}
Commit	Line	Data
f6227721 SL	1	#ifndef lint
	2	static char sccsid[] = "@(#)service.c 4.2 %G%";
	3	#endif
852d162d KM	4
	5	#
	6	/*
	7	* UNIX shell
	8	*
	9	* S. R. Bourne
	10	* Bell Telephone Laboratories
	11	*
	12	*/
	13
	14	#include "defs.h"
	15
	16
	17	PROC VOID gsort();
	18
	19	#define ARGMK 01
	20
	21	INT errno;
	22	STRING sysmsg[];
	23
	24	/* fault handling */
	25	#define ENOMEM 12
	26	#define ENOEXEC 8
	27	#define E2BIG 7
	28	#define ENOENT 2
	29	#define ETXTBSY 26
	30
	31
	32
	33	/* service routines for `execute' */
	34
	35	VOID initio(iop)
	36	IOPTR iop;
	37	{
	38	REG STRING ion;
	39	REG INT iof, fd;
	40
	41	IF iop
	42	THEN iof=iop->iofile;
	43	ion=mactrim(iop->ioname);
	44	IF *ion ANDF (flags&noexec)==0
	45	THEN IF iof&IODOC
	46	THEN subst(chkopen(ion),(fd=tmpfil()));
	47	close(fd); fd=chkopen(tmpout); unlink(tmpout);
	48	ELIF iof&IOMOV
	49	THEN IF eq(minus,ion)
	50	THEN fd = -1;
	51	close(iof&IOUFD);
	52	ELIF (fd=stoi(ion))>=USERIO
	53	THEN failed(ion,badfile);
	54	ELSE fd=dup(fd);
	55	FI
	56	ELIF (iof&IOPUT)==0
	57	THEN fd=chkopen(ion);
	58	ELIF flags&rshflg
	59	THEN failed(ion,restricted);
	60	ELIF iof&IOAPP ANDF (fd=open(ion,1))>=0
	61	THEN lseek(fd, 0L, 2);
	62	ELSE fd=create(ion);
	63	FI
	64	IF fd>=0
	65	THEN rename(fd,iof&IOUFD);
	66	FI
	67	FI
68	initio(iop->ionxt);
69	FI
70	}
71
72	STRING getpath(s)
73	STRING s;
74	{
75	REG STRING path;
76	IF any('/',s)
77	THEN IF flags&rshflg
78	THEN failed(s, restricted);
79	ELSE return(nullstr);
80	FI
81	ELIF (path = pathnod.namval)==0
82	THEN return(defpath);
83	ELSE return(cpystak(path));
84	FI
85	}
86
87	INT pathopen(path, name)
88	REG STRING path, name;
89	{
90	REG UFD f;
91
92	REP path=catpath(path,name);
93	PER (f=open(curstak(),0))<0 ANDF path DONE
94	return(f);
95	}
96
97	STRING catpath(path,name)
98	REG STRING path;
99	STRING name;
100	{
101	/* leaves result on top of stack */
102	REG STRING scanp = path,
103	argp = locstak();
104
105	WHILE scanp ANDF scanp!=COLON DO argp++ = scanp++ OD
106	IF scanp!=path THEN *argp++='/' FI
107	IF *scanp==COLON THEN scanp++ FI
108	path=(*scanp ? scanp : 0); scanp=name;
109	WHILE (argp++ = scanp++) DONE
110	return(path);
111	}
112
113	LOCAL STRING xecmsg;
114	LOCAL STRING *xecenv;
115
116	VOID execa(at)
117	STRING at[];
118	{
119	REG STRING path;
120	REG STRING *t = at;
121
122	IF (flags&noexec)==0
123	THEN xecmsg=notfound; path=getpath(*t);
124	namscan(exname);
125	xecenv=setenv();
126	WHILE path=execs(path,t) DONE
127	failed(*t,xecmsg);
128	FI
129	}
130
131	LOCAL STRING execs(ap,t)
132	STRING ap;
133	REG STRING t[];
134	{
135	REG STRING p, prefix;
136
137	prefix=catpath(ap,t[0]);
138	trim(p=curstak());
139
140	sigchk();
141	execve(p, &t[0] ,xecenv);
142	SWITCH errno IN
143
144	case ENOEXEC:
145	flags=0;
146	comdiv=0; ioset=0;
147	clearup(); /* remove open files and for loop junk */
148	IF input THEN close(input) FI
149	close(output); output=2;
150	input=chkopen(p);
151
152	/* band aid to get csh... 2/26/79 */
153	{
154	char c;
155	if (!isatty(input)) {
156	read(input, &c, 1);
157	if (c == '#')
158	gocsh(t, p, xecenv);
159	lseek(input, (long) 0, 0);
160	}
161	}
162
163	/* set up new args */
164	setargs(t);
165	longjmp(subshell,1);
166
167	case ENOMEM:
168	failed(p,toobig);
169
170	case E2BIG:
171	failed(p,arglist);
172
173	case ETXTBSY:
174	failed(p,txtbsy);
175
176	default:
177	xecmsg=badexec;
178	case ENOENT:
179	return(prefix);
180	ENDSW
181	}
182
183	gocsh(t, cp, xecenv)
184	register char *t, cp, **xecenv;
185	{
186	char **newt[1000];
187	register char **p;
188	register int i;
189
190	for (i = 0; t[i]; i++)
191	newt[i+1] = t[i];
192	newt[i+1] = 0;
193	newt[0] = "/bin/csh";
194	newt[1] = cp;
195	execve("/bin/csh", newt, xecenv);
196	}
197
198	/* for processes to be waited for */
199	#define MAXP 20
200	LOCAL INT pwlist[MAXP];
201	LOCAL INT pwc;
202
203	postclr()
204	{
205	REG INT *pw = pwlist;
206
207	WHILE pw <= &pwlist[pwc]
208	DO *pw++ = 0 OD
209	pwc=0;
210	}
211
212	VOID post(pcsid)
213	INT pcsid;
214	{
215	REG INT *pw = pwlist;
216
217	IF pcsid
218	THEN WHILE *pw DO pw++ OD
219	IF pwc >= MAXP-1
220	THEN pw--;
221	ELSE pwc++;
222	FI
223	*pw = pcsid;
224	FI
225	}
226
227	VOID await(i)
228	INT i;
229	{
230	INT rc=0, wx=0;
231	INT w;
232	INT ipwc = pwc;
233
234	post(i);
235	WHILE pwc
236	DO REG INT p;
237	REG INT sig;
238	INT w_hi;
239
240	BEGIN
241	REG INT *pw=pwlist;
242	p=wait(&w);
243	WHILE pw <= &pwlist[ipwc]
244	DO IF *pw==p
245	THEN *pw=0; pwc--;
246	ELSE pw++;
247	FI
248	OD
249	END
250
251	IF p == -1 THEN continue FI
252
253	w_hi = (w>>8)&LOBYTE;
254
255	IF sig = w&0177
256	THEN IF sig == 0177 /* ptrace! return */
257	THEN prs("ptrace: ");
258	sig = w_hi;
259	FI
260	IF sysmsg[sig]
261	THEN IF i!=p ORF (flags&prompt)==0 THEN prp(); prn(p); blank() FI
262	prs(sysmsg[sig]);
263	IF w&0200 THEN prs(coredump) FI
264	FI
265	newline();
266	FI
267
268	IF rc==0
269	THEN rc = (sig ? sig\|SIGFLG : w_hi);
270	FI
271	wx \|= w;
272	OD
273
274	IF wx ANDF flags&errflg
275	THEN exitsh(rc);
276	FI
277	exitval=rc; exitset();
278	}
279
280	BOOL nosubst;
281
282	trim(at)
283	STRING at;
284	{
285	REG STRING p;
286	REG CHAR c;
287	REG CHAR q=0;
288
289	IF p=at
290	THEN WHILE c = *p
291	DO *p++=c&STRIP; q \|= c OD
292	FI
293	nosubst=q&QUOTE;
294	}
295
296	STRING mactrim(s)
297	STRING s;
298	{
299	REG STRING t=macro(s);
300	trim(t);
301	return(t);
302	}
303
304	STRING *scan(argn)
305	INT argn;
306	{
307	REG ARGPTR argp = Rcheat(gchain)&~ARGMK;
308	REG STRING comargn, comargm;
309
310	comargn=getstak(BYTESPERWORDargn+BYTESPERWORD); comargm = comargn += argn; comargn = ENDARGS;
311
312	WHILE argp
313	DO *--comargn = argp->argval;
314	IF argp = argp->argnxt
315	THEN trim(*comargn);
316	FI
317	IF argp==0 ORF Rcheat(argp)&ARGMK
318	THEN gsort(comargn,comargm);
319	comargm = comargn;
320	FI
321	/* Lcheat(argp) &= ~ARGMK; */
322	argp = Rcheat(argp)&~ARGMK;
323	OD
324	return(comargn);
325	}
326
327	LOCAL VOID gsort(from,to)
328	STRING from[], to[];
329	{
330	INT k, m, n;
331	REG INT i, j;
332
333	IF (n=to-from)<=1 THEN return FI
334
335	FOR j=1; j<=n; j*=2 DONE
336
337	FOR m=2*j-1; m/=2;
338	DO k=n-m;
339	FOR j=0; j<k; j++
340	DO FOR i=j; i>=0; i-=m
341	DO REG STRING *fromi; fromi = &from[i];
342	IF cf(fromi[m],fromi[0])>0
343	THEN break;
344	ELSE STRING s; s=fromi[m]; fromi[m]=fromi[0]; fromi[0]=s;
345	FI
346	OD
347	OD
348	OD
349	}
350
351	/* Argument list generation */
352
353	INT getarg(ac)
354	COMPTR ac;
355	{
356	REG ARGPTR argp;
357	REG INT count=0;
358	REG COMPTR c;
359
360	IF c=ac
361	THEN argp=c->comarg;
362	WHILE argp
363	DO count += split(macro(argp->argval));
364	argp=argp->argnxt;
365	OD
366	FI
367	return(count);
368	}
369
370	LOCAL INT split(s)
371	REG STRING s;
372	{
373	REG STRING argp;
374	REG INT c;
375	INT count=0;
376
377	LOOP sigchk(); argp=locstak()+BYTESPERWORD;
378	WHILE (c = *s++, !any(c,ifsnod.namval) && c)
379	DO *argp++ = c OD
380	IF argp==staktop+BYTESPERWORD
381	THEN IF c
382	THEN continue;
383	ELSE return(count);
384	FI
385	ELIF c==0
386	THEN s--;
387	FI
388	IF c=expand((argp=endstak(argp))->argval,0)
389	THEN count += c;
390	ELSE /* assign(&fngnod, argp->argval); */
391	makearg(argp); count++;
392	FI
393	Lcheat(gchain) \|= ARGMK;
394	POOL
395	}