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

/*	service.c	4.1	82/05/07	*/

#
/*
 * 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
852d162d KM	1	/* service.c 4.1 82/05/07 */
	2
	3	#
	4	/*
	5	* UNIX shell
	6	*
	7	* S. R. Bourne
	8	* Bell Telephone Laboratories
	9	*
	10	*/
	11
	12	#include "defs.h"
	13
	14
	15	PROC VOID gsort();
	16
	17	#define ARGMK 01
	18
	19	INT errno;
	20	STRING sysmsg[];
	21
	22	/* fault handling */
	23	#define ENOMEM 12
	24	#define ENOEXEC 8
	25	#define E2BIG 7
	26	#define ENOENT 2
	27	#define ETXTBSY 26
	28
	29
	30
	31	/* service routines for `execute' */
	32
	33	VOID initio(iop)
	34	IOPTR iop;
	35	{
	36	REG STRING ion;
	37	REG INT iof, fd;
	38
	39	IF iop
	40	THEN iof=iop->iofile;
	41	ion=mactrim(iop->ioname);
	42	IF *ion ANDF (flags&noexec)==0
	43	THEN IF iof&IODOC
	44	THEN subst(chkopen(ion),(fd=tmpfil()));
	45	close(fd); fd=chkopen(tmpout); unlink(tmpout);
	46	ELIF iof&IOMOV
	47	THEN IF eq(minus,ion)
	48	THEN fd = -1;
	49	close(iof&IOUFD);
	50	ELIF (fd=stoi(ion))>=USERIO
	51	THEN failed(ion,badfile);
	52	ELSE fd=dup(fd);
	53	FI
	54	ELIF (iof&IOPUT)==0
	55	THEN fd=chkopen(ion);
	56	ELIF flags&rshflg
	57	THEN failed(ion,restricted);
	58	ELIF iof&IOAPP ANDF (fd=open(ion,1))>=0
	59	THEN lseek(fd, 0L, 2);
	60	ELSE fd=create(ion);
	61	FI
	62	IF fd>=0
	63	THEN rename(fd,iof&IOUFD);
	64	FI
65	FI
66	initio(iop->ionxt);
67	FI
68	}
69
70	STRING getpath(s)
71	STRING s;
72	{
73	REG STRING path;
74	IF any('/',s)
75	THEN IF flags&rshflg
76	THEN failed(s, restricted);
77	ELSE return(nullstr);
78	FI
79	ELIF (path = pathnod.namval)==0
80	THEN return(defpath);
81	ELSE return(cpystak(path));
82	FI
83	}
84
85	INT pathopen(path, name)
86	REG STRING path, name;
87	{
88	REG UFD f;
89
90	REP path=catpath(path,name);
91	PER (f=open(curstak(),0))<0 ANDF path DONE
92	return(f);
93	}
94
95	STRING catpath(path,name)
96	REG STRING path;
97	STRING name;
98	{
99	/* leaves result on top of stack */
100	REG STRING scanp = path,
101	argp = locstak();
102
103	WHILE scanp ANDF scanp!=COLON DO argp++ = scanp++ OD
104	IF scanp!=path THEN *argp++='/' FI
105	IF *scanp==COLON THEN scanp++ FI
106	path=(*scanp ? scanp : 0); scanp=name;
107	WHILE (argp++ = scanp++) DONE
108	return(path);
109	}
110
111	LOCAL STRING xecmsg;
112	LOCAL STRING *xecenv;
113
114	VOID execa(at)
115	STRING at[];
116	{
117	REG STRING path;
118	REG STRING *t = at;
119
120	IF (flags&noexec)==0
121	THEN xecmsg=notfound; path=getpath(*t);
122	namscan(exname);
123	xecenv=setenv();
124	WHILE path=execs(path,t) DONE
125	failed(*t,xecmsg);
126	FI
127	}
128
129	LOCAL STRING execs(ap,t)
130	STRING ap;
131	REG STRING t[];
132	{
133	REG STRING p, prefix;
134
135	prefix=catpath(ap,t[0]);
136	trim(p=curstak());
137
138	sigchk();
139	execve(p, &t[0] ,xecenv);
140	SWITCH errno IN
141
142	case ENOEXEC:
143	flags=0;
144	comdiv=0; ioset=0;
145	clearup(); /* remove open files and for loop junk */
146	IF input THEN close(input) FI
147	close(output); output=2;
148	input=chkopen(p);
149
150	/* band aid to get csh... 2/26/79 */
151	{
152	char c;
153	if (!isatty(input)) {
154	read(input, &c, 1);
155	if (c == '#')
156	gocsh(t, p, xecenv);
157	lseek(input, (long) 0, 0);
158	}
159	}
160
161	/* set up new args */
162	setargs(t);
163	longjmp(subshell,1);
164
165	case ENOMEM:
166	failed(p,toobig);
167
168	case E2BIG:
169	failed(p,arglist);
170
171	case ETXTBSY:
172	failed(p,txtbsy);
173
174	default:
175	xecmsg=badexec;
176	case ENOENT:
177	return(prefix);
178	ENDSW
179	}
180
181	gocsh(t, cp, xecenv)
182	register char *t, cp, **xecenv;
183	{
184	char **newt[1000];
185	register char **p;
186	register int i;
187
188	for (i = 0; t[i]; i++)
189	newt[i+1] = t[i];
190	newt[i+1] = 0;
191	newt[0] = "/bin/csh";
192	newt[1] = cp;
193	execve("/bin/csh", newt, xecenv);
194	}
195
196	/* for processes to be waited for */
197	#define MAXP 20
198	LOCAL INT pwlist[MAXP];
199	LOCAL INT pwc;
200
201	postclr()
202	{
203	REG INT *pw = pwlist;
204
205	WHILE pw <= &pwlist[pwc]
206	DO *pw++ = 0 OD
207	pwc=0;
208	}
209
210	VOID post(pcsid)
211	INT pcsid;
212	{
213	REG INT *pw = pwlist;
214
215	IF pcsid
216	THEN WHILE *pw DO pw++ OD
217	IF pwc >= MAXP-1
218	THEN pw--;
219	ELSE pwc++;
220	FI
221	*pw = pcsid;
222	FI
223	}
224
225	VOID await(i)
226	INT i;
227	{
228	INT rc=0, wx=0;
229	INT w;
230	INT ipwc = pwc;
231
232	post(i);
233	WHILE pwc
234	DO REG INT p;
235	REG INT sig;
236	INT w_hi;
237
238	BEGIN
239	REG INT *pw=pwlist;
240	p=wait(&w);
241	WHILE pw <= &pwlist[ipwc]
242	DO IF *pw==p
243	THEN *pw=0; pwc--;
244	ELSE pw++;
245	FI
246	OD
247	END
248
249	IF p == -1 THEN continue FI
250
251	w_hi = (w>>8)&LOBYTE;
252
253	IF sig = w&0177
254	THEN IF sig == 0177 /* ptrace! return */
255	THEN prs("ptrace: ");
256	sig = w_hi;
257	FI
258	IF sysmsg[sig]
259	THEN IF i!=p ORF (flags&prompt)==0 THEN prp(); prn(p); blank() FI
260	prs(sysmsg[sig]);
261	IF w&0200 THEN prs(coredump) FI
262	FI
263	newline();
264	FI
265
266	IF rc==0
267	THEN rc = (sig ? sig\|SIGFLG : w_hi);
268	FI
269	wx \|= w;
270	OD
271
272	IF wx ANDF flags&errflg
273	THEN exitsh(rc);
274	FI
275	exitval=rc; exitset();
276	}
277
278	BOOL nosubst;
279
280	trim(at)
281	STRING at;
282	{
283	REG STRING p;
284	REG CHAR c;
285	REG CHAR q=0;
286
287	IF p=at
288	THEN WHILE c = *p
289	DO *p++=c&STRIP; q \|= c OD
290	FI
291	nosubst=q&QUOTE;
292	}
293
294	STRING mactrim(s)
295	STRING s;
296	{
297	REG STRING t=macro(s);
298	trim(t);
299	return(t);
300	}
301
302	STRING *scan(argn)
303	INT argn;
304	{
305	REG ARGPTR argp = Rcheat(gchain)&~ARGMK;
306	REG STRING comargn, comargm;
307
308	comargn=getstak(BYTESPERWORDargn+BYTESPERWORD); comargm = comargn += argn; comargn = ENDARGS;
309
310	WHILE argp
311	DO *--comargn = argp->argval;
312	IF argp = argp->argnxt
313	THEN trim(*comargn);
314	FI
315	IF argp==0 ORF Rcheat(argp)&ARGMK
316	THEN gsort(comargn,comargm);
317	comargm = comargn;
318	FI
319	/* Lcheat(argp) &= ~ARGMK; */
320	argp = Rcheat(argp)&~ARGMK;
321	OD
322	return(comargn);
323	}
324
325	LOCAL VOID gsort(from,to)
326	STRING from[], to[];
327	{
328	INT k, m, n;
329	REG INT i, j;
330
331	IF (n=to-from)<=1 THEN return FI
332
333	FOR j=1; j<=n; j*=2 DONE
334
335	FOR m=2*j-1; m/=2;
336	DO k=n-m;
337	FOR j=0; j<k; j++
338	DO FOR i=j; i>=0; i-=m
339	DO REG STRING *fromi; fromi = &from[i];
340	IF cf(fromi[m],fromi[0])>0
341	THEN break;
342	ELSE STRING s; s=fromi[m]; fromi[m]=fromi[0]; fromi[0]=s;
343	FI
344	OD
345	OD
346	OD
347	}
348
349	/* Argument list generation */
350
351	INT getarg(ac)
352	COMPTR ac;
353	{
354	REG ARGPTR argp;
355	REG INT count=0;
356	REG COMPTR c;
357
358	IF c=ac
359	THEN argp=c->comarg;
360	WHILE argp
361	DO count += split(macro(argp->argval));
362	argp=argp->argnxt;
363	OD
364	FI
365	return(count);
366	}
367
368	LOCAL INT split(s)
369	REG STRING s;
370	{
371	REG STRING argp;
372	REG INT c;
373	INT count=0;
374
375	LOOP sigchk(); argp=locstak()+BYTESPERWORD;
376	WHILE (c = *s++, !any(c,ifsnod.namval) && c)
377	DO *argp++ = c OD
378	IF argp==staktop+BYTESPERWORD
379	THEN IF c
380	THEN continue;
381	ELSE return(count);
382	FI
383	ELIF c==0
384	THEN s--;
385	FI
386	IF c=expand((argp=endstak(argp))->argval,0)
387	THEN count += c;
388	ELSE /* assign(&fngnod, argp->argval); */
389	makearg(argp); count++;
390	FI
391	Lcheat(gchain) \|= ARGMK;
392	POOL
393	}