xref: /csrg-svn/usr.bin/file/file.c (revision 6719)
1*6719Smckusick static	char sccsid[] = "@(#)file.c	4.4 (Berkeley) 4.4";
2613Sbill /*
3613Sbill  * file - determine type of file
4613Sbill  */
5613Sbill 
6613Sbill #include <pagsiz.h>
7613Sbill #include <sys/types.h>
8613Sbill #include <stat.h>
9613Sbill #include <stdio.h>
10613Sbill #include <ctype.h>
11904Sbill #include <a.out.h>
12613Sbill int in;
13613Sbill int i  = 0;
14613Sbill char buf[BUFSIZ];
15613Sbill char *troff[] = {	/* new troff intermediate lang */
16613Sbill 	"x","T","res","init","font","202","V0","p1",0};
17613Sbill char *fort[] = {
18613Sbill 	"function","subroutine","common","dimension","block","integer",
19613Sbill 	"real","data","double",0};
20613Sbill char *asc[] = {
21613Sbill 	"chmk","mov","tst","clr","jmp",0};
22613Sbill char *c[] = {
23613Sbill 	"int","char","float","double","struct","extern",0};
24613Sbill char *as[] = {
25613Sbill 	"globl","byte","align","text","data","comm",0};
26613Sbill int	ifile;
27613Sbill 
28613Sbill main(argc, argv)
29613Sbill char **argv;
30613Sbill {
31613Sbill 	FILE *fl;
32613Sbill 	register char *p;
33613Sbill 	char ap[128];
34613Sbill 	extern char _sobuf[];
35613Sbill 
36613Sbill 	if (argc>1 && argv[1][0]=='-' && argv[1][1]=='f') {
37613Sbill 		if ((fl = fopen(argv[2], "r")) == NULL) {
38613Sbill 			printf("Can't open %s\n", argv[2]);
39613Sbill 			exit(2);
40613Sbill 		}
41613Sbill 		while ((p = fgets(ap, 128, fl)) != NULL) {
42613Sbill 			int l = strlen(p);
43613Sbill 			if (l>0)
44613Sbill 				p[l-1] = '\0';
45613Sbill 			printf("%s:	", p);
46613Sbill 			type(p);
47613Sbill 			if (ifile>=0)
48613Sbill 				close(ifile);
49613Sbill 		}
50613Sbill 		exit(1);
51613Sbill 	}
52613Sbill 	while(argc > 1) {
53613Sbill 		printf("%s:	", argv[1]);
54613Sbill 		type(argv[1]);
55613Sbill 		fflush(stdout);
56613Sbill 		argc--;
57613Sbill 		argv++;
58613Sbill 		if (ifile >= 0)
59613Sbill 			close(ifile);
60613Sbill 	}
61613Sbill }
62613Sbill 
63613Sbill type(file)
64613Sbill char *file;
65613Sbill {
66613Sbill 	int j,nl;
67613Sbill 	char ch;
68613Sbill 	struct stat mbuf;
69613Sbill 
70613Sbill 	ifile = -1;
71*6719Smckusick 	if (lstat(file, &mbuf) < 0) {
72613Sbill 		printf("cannot stat\n");
73613Sbill 		return;
74613Sbill 	}
75613Sbill 	switch (mbuf.st_mode & S_IFMT) {
76613Sbill 
77613Sbill 	case S_IFCHR:
78613Sbill 		printf("character");
79613Sbill 		goto spcl;
80613Sbill 
81*6719Smckusick 	case S_IFLNK:
82*6719Smckusick 		printf("symbolic link\n");
83*6719Smckusick 		return;
84*6719Smckusick 
85613Sbill 	case S_IFDIR:
86613Sbill 		printf("directory\n");
87613Sbill 		return;
88613Sbill 
89613Sbill 	case S_IFBLK:
90613Sbill 		printf("block");
91613Sbill 
92613Sbill spcl:
93613Sbill 		printf(" special (%d/%d)\n", major(mbuf.st_rdev), minor(mbuf.st_rdev));
94613Sbill 		return;
95613Sbill 	}
96613Sbill 
97613Sbill 	ifile = open(file, 0);
98613Sbill 	if(ifile < 0) {
99613Sbill 		printf("cannot open\n");
100613Sbill 		return;
101613Sbill 	}
102613Sbill 	in = read(ifile, buf, BUFSIZ);
103613Sbill 	if(in == 0){
104613Sbill 		printf("empty\n");
105613Sbill 		return;
106613Sbill 	}
107613Sbill 	switch(*(int *)buf) {
108613Sbill 
109613Sbill 	case 0413:
110613Sbill 		printf("demand paged ");
111613Sbill 
112613Sbill 	case 0410:
113613Sbill 		printf("pure ");
114613Sbill 		goto exec;
115613Sbill 
116613Sbill 	case 0411:
117613Sbill 		printf("jfr or pdp-11 unix 411 executable\n");
118613Sbill 		return;
119613Sbill 
120613Sbill 	case 0407:
121613Sbill exec:
122613Sbill 		printf("executable");
123613Sbill 		if(((int *)buf)[4] != 0) {
124613Sbill 			printf(" not stripped");
125613Sbill 			if(oldo(buf))
126613Sbill 				printf(" (old format symbol table)");
127613Sbill 		}
128613Sbill 		printf("\n");
129613Sbill 		goto out;
130613Sbill 
131613Sbill 	case 0177555:
132613Sbill 		printf("very old archive\n");
133613Sbill 		goto out;
134613Sbill 
135613Sbill 	case 0177545:
136613Sbill 		printf("old archive\n");
137613Sbill 		goto out;
138897Sbill 
139897Sbill 	case 070707:
140897Sbill 		printf("cpio data\n");
141897Sbill 		goto out;
142613Sbill 	}
143613Sbill 
144613Sbill 	if(strncmp(buf, "!<arch>\n__.SYMDEF", 17) == 0 ) {
145613Sbill 		printf("archive random library\n");
146613Sbill 		goto out;
147613Sbill 	}
148613Sbill 	if (strncmp(buf, "!<arch>\n", 8)==0) {
149613Sbill 		printf("archive\n");
150613Sbill 		goto out;
151613Sbill 	}
1525900Sroot 	if (mbuf.st_size % 512 == 0) {	/* it may be a PRESS file */
1535900Sroot 		lseek(ifile, -512L, 2);	/* last block */
1545900Sroot 		if (read(ifile, buf, BUFSIZ) > 0
1555900Sroot 		 && *(short int *)buf == 12138) {
1565900Sroot 			printf("PRESS file\n");
1575900Sroot 			goto out;
1585900Sroot 		}
1595900Sroot 	}
160613Sbill 	i = 0;
161613Sbill 	if(ccom() == 0)goto notc;
162613Sbill 	while(buf[i] == '#'){
163613Sbill 		j = i;
164613Sbill 		while(buf[i++] != '\n'){
165613Sbill 			if(i - j > 255){
166613Sbill 				printf("data\n");
167613Sbill 				goto out;
168613Sbill 			}
169613Sbill 			if(i >= in)goto notc;
170613Sbill 		}
171613Sbill 		if(ccom() == 0)goto notc;
172613Sbill 	}
173613Sbill check:
174613Sbill 	if(lookup(c) == 1){
175613Sbill 		while((ch = buf[i++]) != ';' && ch != '{')if(i >= in)goto notc;
176613Sbill 		printf("c program text");
177613Sbill 		goto outa;
178613Sbill 	}
179613Sbill 	nl = 0;
180613Sbill 	while(buf[i] != '('){
181613Sbill 		if(buf[i] <= 0)
182613Sbill 			goto notas;
183613Sbill 		if(buf[i] == ';'){
184613Sbill 			i++;
185613Sbill 			goto check;
186613Sbill 		}
187613Sbill 		if(buf[i++] == '\n')
188613Sbill 			if(nl++ > 6)goto notc;
189613Sbill 		if(i >= in)goto notc;
190613Sbill 	}
191613Sbill 	while(buf[i] != ')'){
192613Sbill 		if(buf[i++] == '\n')
193613Sbill 			if(nl++ > 6)goto notc;
194613Sbill 		if(i >= in)goto notc;
195613Sbill 	}
196613Sbill 	while(buf[i] != '{'){
197613Sbill 		if(buf[i++] == '\n')
198613Sbill 			if(nl++ > 6)goto notc;
199613Sbill 		if(i >= in)goto notc;
200613Sbill 	}
201613Sbill 	printf("c program text");
202613Sbill 	goto outa;
203613Sbill notc:
204613Sbill 	i = 0;
205613Sbill 	while(buf[i] == 'c' || buf[i] == '#'){
206613Sbill 		while(buf[i++] != '\n')if(i >= in)goto notfort;
207613Sbill 	}
208613Sbill 	if(lookup(fort) == 1){
209613Sbill 		printf("fortran program text");
210613Sbill 		goto outa;
211613Sbill 	}
212613Sbill notfort:
213613Sbill 	i=0;
214613Sbill 	if(ascom() == 0)goto notas;
215613Sbill 	j = i-1;
216613Sbill 	if(buf[i] == '.'){
217613Sbill 		i++;
218613Sbill 		if(lookup(as) == 1){
219613Sbill 			printf("assembler program text");
220613Sbill 			goto outa;
221613Sbill 		}
222613Sbill 		else if(buf[j] == '\n' && isalpha(buf[j+2])){
223613Sbill 			printf("roff, nroff, or eqn input text");
224613Sbill 			goto outa;
225613Sbill 		}
226613Sbill 	}
227613Sbill 	while(lookup(asc) == 0){
228613Sbill 		if(ascom() == 0)goto notas;
229613Sbill 		while(buf[i] != '\n' && buf[i++] != ':')
230613Sbill 			if(i >= in)goto notas;
231613Sbill 		while(buf[i] == '\n' || buf[i] == ' ' || buf[i] == '\t')if(i++ >= in)goto notas;
232613Sbill 		j = i-1;
233613Sbill 		if(buf[i] == '.'){
234613Sbill 			i++;
235613Sbill 			if(lookup(as) == 1){
236613Sbill 				printf("assembler program text");
237613Sbill 				goto outa;
238613Sbill 			}
239613Sbill 			else if(buf[j] == '\n' && isalpha(buf[j+2])){
240613Sbill 				printf("roff, nroff, or eqn input text");
241613Sbill 				goto outa;
242613Sbill 			}
243613Sbill 		}
244613Sbill 	}
245613Sbill 	printf("assembler program text");
246613Sbill 	goto outa;
247613Sbill notas:
248613Sbill 	for(i=0; i < in; i++)if(buf[i]&0200){
249613Sbill 		if (buf[0]=='\100' && buf[1]=='\357') {
250613Sbill 			printf("troff (CAT) output\n");
251613Sbill 			goto out;
252613Sbill 		}
253613Sbill 		printf("data\n");
254613Sbill 		goto out;
255613Sbill 	}
256613Sbill 	if (mbuf.st_mode&((S_IEXEC)|(S_IEXEC>>3)|(S_IEXEC>>6)))
257613Sbill 		printf("commands text");
258613Sbill 	else if (troffint(buf, in))
259613Sbill 		printf("troff intermediate output text");
260613Sbill 	else if (english(buf, in))
261613Sbill 		printf("English text");
262613Sbill 	else
263613Sbill 		printf("ascii text");
264613Sbill outa:
265613Sbill 	while(i < in)
266613Sbill 		if((buf[i++]&0377) > 127){
267613Sbill 			printf(" with garbage\n");
268613Sbill 			goto out;
269613Sbill 		}
270613Sbill 	/* if next few lines in then read whole file looking for nulls ...
271613Sbill 		while((in = read(ifile,buf,BUFSIZ)) > 0)
272613Sbill 			for(i = 0; i < in; i++)
273613Sbill 				if((buf[i]&0377) > 127){
274613Sbill 					printf(" with garbage\n");
275613Sbill 					goto out;
276613Sbill 				}
277613Sbill 		/*.... */
278613Sbill 	printf("\n");
279613Sbill out:;
280613Sbill }
281613Sbill 
282613Sbill oldo(cp)
283613Sbill char *cp;
284613Sbill {
285613Sbill 	struct exec ex;
286613Sbill 	struct stat stb;
287613Sbill 
288613Sbill 	ex = *(struct exec *)cp;
289613Sbill 	if (fstat(ifile, &stb) < 0)
290613Sbill 		return(0);
291613Sbill 	if (N_STROFF(ex)+sizeof(off_t) > stb.st_size)
292613Sbill 		return (1);
293613Sbill 	return (0);
294613Sbill }
295613Sbill 
296613Sbill 
297613Sbill 
298613Sbill troffint(bp, n)
299613Sbill char *bp;
300613Sbill int n;
301613Sbill {
302613Sbill 	int k;
303613Sbill 
304613Sbill 	i = 0;
305613Sbill 	for (k = 0; k < 6; k++) {
306613Sbill 		if (lookup(troff) == 0)
307613Sbill 			return(0);
308613Sbill 		if (lookup(troff) == 0)
309613Sbill 			return(0);
310613Sbill 		while (i < n && buf[i] != '\n')
311613Sbill 			i++;
312613Sbill 		if (i++ >= n)
313613Sbill 			return(0);
314613Sbill 	}
315613Sbill 	return(1);
316613Sbill }
317613Sbill lookup(tab)
318613Sbill char *tab[];
319613Sbill {
320613Sbill 	char r;
321613Sbill 	int k,j,l;
322613Sbill 	while(buf[i] == ' ' || buf[i] == '\t' || buf[i] == '\n')i++;
323613Sbill 	for(j=0; tab[j] != 0; j++){
324613Sbill 		l=0;
325613Sbill 		for(k=i; ((r=tab[j][l++]) == buf[k] && r != '\0');k++);
326613Sbill 		if(r == '\0')
327613Sbill 			if(buf[k] == ' ' || buf[k] == '\n' || buf[k] == '\t'
328613Sbill 			    || buf[k] == '{' || buf[k] == '/'){
329613Sbill 				i=k;
330613Sbill 				return(1);
331613Sbill 			}
332613Sbill 	}
333613Sbill 	return(0);
334613Sbill }
335613Sbill ccom(){
336613Sbill 	char cc;
337613Sbill 	while((cc = buf[i]) == ' ' || cc == '\t' || cc == '\n')if(i++ >= in)return(0);
338613Sbill 	if(buf[i] == '/' && buf[i+1] == '*'){
339613Sbill 		i += 2;
340613Sbill 		while(buf[i] != '*' || buf[i+1] != '/'){
341613Sbill 			if(buf[i] == '\\')i += 2;
342613Sbill 			else i++;
343613Sbill 			if(i >= in)return(0);
344613Sbill 		}
345613Sbill 		if((i += 2) >= in)return(0);
346613Sbill 	}
347613Sbill 	if(buf[i] == '\n')if(ccom() == 0)return(0);
348613Sbill 	return(1);
349613Sbill }
350613Sbill ascom(){
351613Sbill 	while(buf[i] == '/'){
352613Sbill 		i++;
353613Sbill 		while(buf[i++] != '\n')if(i >= in)return(0);
354613Sbill 		while(buf[i] == '\n')if(i++ >= in)return(0);
355613Sbill 	}
356613Sbill 	return(1);
357613Sbill }
358613Sbill 
359613Sbill english (bp, n)
360613Sbill char *bp;
361613Sbill {
362613Sbill # define NASC 128
363613Sbill 	int ct[NASC], j, vow, freq, rare;
364613Sbill 	int badpun = 0, punct = 0;
365613Sbill 	if (n<50) return(0); /* no point in statistics on squibs */
366613Sbill 	for(j=0; j<NASC; j++)
367613Sbill 		ct[j]=0;
368613Sbill 	for(j=0; j<n; j++)
369613Sbill 	{
370613Sbill 		if (bp[j]<NASC)
371613Sbill 			ct[bp[j]|040]++;
372613Sbill 		switch (bp[j])
373613Sbill 		{
374613Sbill 		case '.':
375613Sbill 		case ',':
376613Sbill 		case ')':
377613Sbill 		case '%':
378613Sbill 		case ';':
379613Sbill 		case ':':
380613Sbill 		case '?':
381613Sbill 			punct++;
382613Sbill 			if ( j < n-1 &&
383613Sbill 			    bp[j+1] != ' ' &&
384613Sbill 			    bp[j+1] != '\n')
385613Sbill 				badpun++;
386613Sbill 		}
387613Sbill 	}
388613Sbill 	if (badpun*5 > punct)
389613Sbill 		return(0);
390613Sbill 	vow = ct['a'] + ct['e'] + ct['i'] + ct['o'] + ct['u'];
391613Sbill 	freq = ct['e'] + ct['t'] + ct['a'] + ct['i'] + ct['o'] + ct['n'];
392613Sbill 	rare = ct['v'] + ct['j'] + ct['k'] + ct['q'] + ct['x'] + ct['z'];
393613Sbill 	if (2*ct[';'] > ct['e']) return(0);
394613Sbill 	if ( (ct['>']+ct['<']+ct['/'])>ct['e']) return(0); /* shell file test */
395613Sbill 	return (vow*5 >= n-ct[' '] && freq >= 10*rare);
396613Sbill }
397