1 /*
2  * POSIX standard
3  *	test expression
4  *	[ expression ]
5  *
6  * Plan 9 additions:
7  *	-A file exists and is append-only
8  *	-L file exists and is exclusive-use
9  *	-T file exists and is temporary
10  */
11 
12 #include <u.h>
13 #include <libc.h>
14 
15 #define isatty plan9_isatty
16 
17 #define EQ(a,b)	((tmp=a)==0?0:(strcmp(tmp,b)==0))
18 
19 int	ap;
20 int	ac;
21 char	**av;
22 char	*tmp;
23 
24 void	synbad(char *, char *);
25 int	fsizep(char *);
26 int	isdir(char *);
27 int	isreg(char *);
28 int	isatty(int);
29 int	isint(char *, int *);
30 int	isolder(char *, char *);
31 int	isolderthan(char *, char *);
32 int	isnewerthan(char *, char *);
33 int	hasmode(char *, ulong);
34 int	tio(char *, int);
35 int	e(void), e1(void), e2(void), e3(void);
36 char	*nxtarg(int);
37 
38 void
39 main(int argc, char *argv[])
40 {
41 	int r;
42 	char *c;
43 
44 	ac = argc; av = argv; ap = 1;
45 	if(EQ(argv[0],"[")) {
46 		if(!EQ(argv[--ac],"]"))
47 			synbad("] missing","");
48 	}
49 	argv[ac] = 0;
50 	if (ac<=1)
51 		exits("usage");
52 	r = e();
53 	/*
54 	 * nice idea but short-circuit -o and -a operators may have
55 	 * not consumed their right-hand sides.
56 	 */
57 	if(0 && (c = nxtarg(1)) != nil)
58 		synbad("unexpected operator/operand: ", c);
59 	exits(r?0:"false");
60 }
61 
62 char *
63 nxtarg(int mt)
64 {
65 	if(ap>=ac){
66 		if(mt){
67 			ap++;
68 			return(0);
69 		}
70 		synbad("argument expected","");
71 	}
72 	return(av[ap++]);
73 }
74 
75 int
76 nxtintarg(int *pans)
77 {
78 	if(ap<ac && isint(av[ap], pans)){
79 		ap++;
80 		return 1;
81 	}
82 	return 0;
83 }
84 
85 int
86 e(void)
87 {
88 	int p1;
89 
90 	p1 = e1();
91 	if (EQ(nxtarg(1), "-o"))
92 		return(p1 || e());
93 	ap--;
94 	return(p1);
95 }
96 
97 int
98 e1(void)
99 {
100 	int p1;
101 
102 	p1 = e2();
103 	if (EQ(nxtarg(1), "-a"))
104 		return (p1 && e1());
105 	ap--;
106 	return(p1);
107 }
108 
109 int
110 e2(void)
111 {
112 	if (EQ(nxtarg(0), "!"))
113 		return(!e2());
114 	ap--;
115 	return(e3());
116 }
117 
118 int
119 e3(void)
120 {
121 	int p1, int1, int2;
122 	char *a, *p2;
123 
124 	a = nxtarg(0);
125 	if(EQ(a, "(")) {
126 		p1 = e();
127 		if(!EQ(nxtarg(0), ")"))
128 			synbad(") expected","");
129 		return(p1);
130 	}
131 
132 	if(EQ(a, "-A"))
133 		return(hasmode(nxtarg(0), DMAPPEND));
134 
135 	if(EQ(a, "-L"))
136 		return(hasmode(nxtarg(0), DMEXCL));
137 
138 	if(EQ(a, "-T"))
139 		return(hasmode(nxtarg(0), DMTMP));
140 
141 	if(EQ(a, "-f"))
142 		return(isreg(nxtarg(0)));
143 
144 	if(EQ(a, "-d"))
145 		return(isdir(nxtarg(0)));
146 
147 	if(EQ(a, "-r"))
148 		return(tio(nxtarg(0), 4));
149 
150 	if(EQ(a, "-w"))
151 		return(tio(nxtarg(0), 2));
152 
153 	if(EQ(a, "-x"))
154 		return(tio(nxtarg(0), 1));
155 
156 	if(EQ(a, "-e"))
157 		return(tio(nxtarg(0), 0));
158 
159 	if(EQ(a, "-c"))
160 		return(0);
161 
162 	if(EQ(a, "-b"))
163 		return(0);
164 
165 	if(EQ(a, "-u"))
166 		return(0);
167 
168 	if(EQ(a, "-g"))
169 		return(0);
170 
171 	if(EQ(a, "-s"))
172 		return(fsizep(nxtarg(0)));
173 
174 	if(EQ(a, "-t"))
175 		if(ap>=ac)
176 			return(isatty(1));
177 		else if(nxtintarg(&int1))
178 			return(isatty(int1));
179 		else
180 			synbad("not a valid file descriptor number ", "");
181 
182 	if(EQ(a, "-n"))
183 		return(!EQ(nxtarg(0), ""));
184 	if(EQ(a, "-z"))
185 		return(EQ(nxtarg(0), ""));
186 
187 	p2 = nxtarg(1);
188 	if (p2==0)
189 		return(!EQ(a,""));
190 	if(EQ(p2, "="))
191 		return(EQ(nxtarg(0), a));
192 
193 	if(EQ(p2, "!="))
194 		return(!EQ(nxtarg(0), a));
195 
196 	if(EQ(p2, "-older"))
197 		return(isolder(nxtarg(0), a));
198 
199 	if(EQ(p2, "-ot"))
200 		return(isolderthan(nxtarg(0), a));
201 
202 	if(EQ(p2, "-nt"))
203 		return(isnewerthan(nxtarg(0), a));
204 
205 	if(!isint(a, &int1))
206 		synbad("unexpected operator/operand: ", p2);
207 
208 	if(nxtintarg(&int2)){
209 		if(EQ(p2, "-eq"))
210 			return(int1==int2);
211 		if(EQ(p2, "-ne"))
212 			return(int1!=int2);
213 		if(EQ(p2, "-gt"))
214 			return(int1>int2);
215 		if(EQ(p2, "-lt"))
216 			return(int1<int2);
217 		if(EQ(p2, "-ge"))
218 			return(int1>=int2);
219 		if(EQ(p2, "-le"))
220 			return(int1<=int2);
221 	}
222 
223 	synbad("unknown operator ",p2);
224 	return 0;		/* to shut ken up */
225 }
226 
227 int
228 tio(char *a, int f)
229 {
230 	return access (a, f) >= 0;
231 }
232 
233 /*
234  * note that the name strings pointed to by Dir members are
235  * allocated with the Dir itself (by the same call to malloc),
236  * but are not included in sizeof(Dir), so copying a Dir won't
237  * copy the strings it points to.
238  */
239 
240 int
241 hasmode(char *f, ulong m)
242 {
243 	int r;
244 	Dir *dir;
245 
246 	dir = dirstat(f);
247 	if (dir == nil)
248 		return 0;
249 	r = (dir->mode & m) != 0;
250 	free(dir);
251 	return r;
252 }
253 
254 int
255 isdir(char *f)
256 {
257 	return hasmode(f, DMDIR);
258 }
259 
260 int
261 isreg(char *f)
262 {
263 	int r;
264 	Dir *dir;
265 
266 	dir = dirstat(f);
267 	if (dir == nil)
268 		return 0;
269 	r = (dir->mode & DMDIR) == 0;
270 	free(dir);
271 	return r;
272 }
273 
274 int
275 isatty(int fd)
276 {
277 	int r;
278 	Dir *d1, *d2;
279 
280 	d1 = dirfstat(fd);
281 	d2 = dirstat("/dev/cons");
282 	if (d1 == nil || d2 == nil)
283 		r = 0;
284 	else
285 		r = d1->type == d2->type && d1->dev == d2->dev &&
286 			d1->qid.path == d2->qid.path;
287 	free(d1);
288 	free(d2);
289 	return r;
290 }
291 
292 int
293 fsizep(char *f)
294 {
295 	int r;
296 	Dir *dir;
297 
298 	dir = dirstat(f);
299 	if (dir == nil)
300 		return 0;
301 	r = dir->length > 0;
302 	free(dir);
303 	return r;
304 }
305 
306 void
307 synbad(char *s1, char *s2)
308 {
309 	int len;
310 
311 	write(2, "test: ", 6);
312 	if ((len = strlen(s1)) != 0)
313 		write(2, s1, len);
314 	if ((len = strlen(s2)) != 0)
315 		write(2, s2, len);
316 	write(2, "\n", 1);
317 	exits("bad syntax");
318 }
319 
320 int
321 isint(char *s, int *pans)
322 {
323 	char *ep;
324 
325 	*pans = strtol(s, &ep, 0);
326 	return (*ep == 0);
327 }
328 
329 int
330 isolder(char *pin, char *f)
331 {
332 	int r;
333 	ulong n, m;
334 	char *p = pin;
335 	Dir *dir;
336 
337 	dir = dirstat(f);
338 	if (dir == nil)
339 		return 0;
340 
341 	/* parse time */
342 	n = 0;
343 	while(*p){
344 		m = strtoul(p, &p, 0);
345 		switch(*p){
346 		case 0:
347 			n = m;
348 			break;
349 		case 'y':
350 			m *= 12;
351 			/* fall through */
352 		case 'M':
353 			m *= 30;
354 			/* fall through */
355 		case 'd':
356 			m *= 24;
357 			/* fall through */
358 		case 'h':
359 			m *= 60;
360 			/* fall through */
361 		case 'm':
362 			m *= 60;
363 			/* fall through */
364 		case 's':
365 			n += m;
366 			p++;
367 			break;
368 		default:
369 			synbad("bad time syntax, ", pin);
370 		}
371 	}
372 
373 	r = dir->mtime + n < time(0);
374 	free(dir);
375 	return r;
376 }
377 
378 int
379 isolderthan(char *a, char *b)
380 {
381 	int r;
382 	Dir *ad, *bd;
383 
384 	ad = dirstat(a);
385 	bd = dirstat(b);
386 	if (ad == nil || bd == nil)
387 		r = 0;
388 	else
389 		r = ad->mtime > bd->mtime;
390 	free(ad);
391 	free(bd);
392 	return r;
393 }
394 
395 int
396 isnewerthan(char *a, char *b)
397 {
398 	int r;
399 	Dir *ad, *bd;
400 
401 	ad = dirstat(a);
402 	bd = dirstat(b);
403 	if (ad == nil || bd == nil)
404 		r = 0;
405 	else
406 		r = ad->mtime < bd->mtime;
407 	free(ad);
408 	free(bd);
409 	return r;
410 }