1 #ifndef lint 2 static char sccsid[] = "@(#)file.c 4.18 (Berkeley) 03/05/91"; 3 #endif 4 /* 5 * file - determine type of file 6 */ 7 8 #include <sys/param.h> 9 #include <sys/stat.h> 10 #include <string.h> 11 #include <stdio.h> 12 #include <ctype.h> 13 #include <a.out.h> 14 15 extern int errno; 16 17 int in; 18 int i = 0; 19 char buf[BUFSIZ]; 20 char *troff[] = { /* new troff intermediate lang */ 21 "x","T","res","init","font","202","V0","p1",0}; 22 char *fort[] = { 23 "function","subroutine","common","dimension","block","integer", 24 "real","data","double",0}; 25 char *asc[] = { 26 "chmk","mov","tst","clr","jmp",0}; 27 char *c[] = { 28 "int","char","float","double","struct","extern",0}; 29 char *as[] = { 30 "globl","byte","align","text","data","comm",0}; 31 char *sh[] = { 32 "fi", "elif", "esac", "done", "export", 33 "readonly", "trap", "PATH", "HOME", 0 }; 34 char *csh[] = { 35 "alias", "breaksw", "endsw", "foreach", "limit", "onintr", 36 "repeat", "setenv", "source", "path", "home", 0 }; 37 int ifile; 38 39 main(argc, argv) 40 char **argv; 41 { 42 FILE *fl; 43 register char *p; 44 char ap[MAXPATHLEN + 1]; 45 46 if (argc < 2) { 47 fprintf(stderr, "usage: %s file ...\n", argv[0]); 48 exit(3); 49 } 50 51 if (argc>1 && argv[1][0]=='-' && argv[1][1]=='f') { 52 if ((fl = fopen(argv[2], "r")) == NULL) { 53 perror(argv[2]); 54 exit(2); 55 } 56 while ((p = fgets(ap, sizeof ap, fl)) != NULL) { 57 int l = strlen(p); 58 if (l>0) 59 p[l-1] = '\0'; 60 type(p); 61 if (ifile>=0) 62 close(ifile); 63 } 64 exit(1); 65 } 66 while(argc > 1) { 67 ifile = -1; 68 type(argv[1]); 69 fflush(stdout); 70 argc--; 71 argv++; 72 if (ifile >= 0) 73 close(ifile); 74 } 75 exit(0); 76 } 77 78 type(file) 79 char *file; 80 { 81 int j,nl; 82 char ch; 83 struct stat mbuf; 84 char slink[MAXPATHLEN + 1]; 85 86 if (lstat(file, &mbuf) < 0) { 87 fprintf(stderr, "file: %s: %s\n", file, strerror(errno)); 88 return; 89 } 90 switch (mbuf.st_mode & S_IFMT) { 91 case S_IFLNK: 92 printf("%s: symbolic link", file); 93 j = readlink(file, slink, sizeof slink - 1); 94 if (j >= 0) { 95 slink[j] = '\0'; 96 printf(" to %s", slink); 97 } 98 printf("\n"); 99 return; 100 101 case S_IFDIR: 102 printf("%s: ", file); 103 if (mbuf.st_mode & S_ISVTX) 104 printf("append-only "); 105 printf("directory\n"); 106 return; 107 108 case S_IFCHR: 109 case S_IFBLK: 110 printf("%s: %s special (%d/%d)\n", file, 111 (mbuf.st_mode&S_IFMT) == S_IFCHR ? "character" : "block", 112 major(mbuf.st_rdev), minor(mbuf.st_rdev)); 113 return; 114 115 case S_IFSOCK: 116 printf("%s: socket\n", file); 117 return; 118 } 119 120 ifile = open(file, 0); 121 if(ifile < 0) { 122 fprintf(stderr, "file: %s: %s\n", file, strerror(errno)); 123 return; 124 } 125 in = read(ifile, buf, BUFSIZ); 126 if(in == 0){ 127 printf("empty\n"); 128 return; 129 } 130 switch(*(int *)buf) { 131 132 case 0413: 133 printf("demand paged "); 134 135 case 0410: 136 printf("pure "); 137 goto exec; 138 139 case 0411: 140 printf("jfr or pdp-11 unix 411 executable\n"); 141 return; 142 143 case 0407: 144 exec: 145 if (mbuf.st_mode & S_ISUID) 146 printf("set-uid "); 147 if (mbuf.st_mode & S_ISGID) 148 printf("set-gid "); 149 if (mbuf.st_mode & S_ISVTX) 150 printf("sticky "); 151 printf("executable"); 152 if(((int *)buf)[4] != 0) { 153 printf(" not stripped"); 154 if(oldo(buf)) 155 printf(" (old format symbol table)"); 156 } 157 printf("\n"); 158 return; 159 160 case 0177555: 161 printf("very old archive\n"); 162 return; 163 164 case 0177545: 165 printf("old archive\n"); 166 return; 167 168 case 070707: 169 printf("cpio data\n"); 170 return; 171 } 172 173 if (buf[0] == '#' && buf[1] == '!' && shellscript(buf+2, &mbuf)) 174 return; 175 if (buf[0] == '\037' && buf[1] == '\235') { 176 if (buf[2]&0x80) 177 printf("block "); 178 printf("compressed %d bit code data\n", buf[2]&0x1f); 179 return; 180 } 181 if(strncmp(buf, "!<arch>\n__.SYMDEF", 17) == 0 ) { 182 printf("archive random library\n"); 183 return; 184 } 185 if (strncmp(buf, "!<arch>\n", 8)==0) { 186 printf("archive\n"); 187 return; 188 } 189 if (mbuf.st_size % 512 == 0) { /* it may be a PRESS file */ 190 lseek(ifile, -512L, 2); /* last block */ 191 if (read(ifile, buf, BUFSIZ) > 0 && *(short *)buf == 12138) { 192 printf("PRESS file\n"); 193 return; 194 } 195 } 196 i = 0; 197 if(ccom() == 0)goto notc; 198 while(buf[i] == '#'){ 199 j = i; 200 while(buf[i++] != '\n'){ 201 if(i - j > 255){ 202 printf("data\n"); 203 return; 204 } 205 if(i >= in)goto notc; 206 } 207 if(ccom() == 0)goto notc; 208 } 209 check: 210 if(lookup(c) == 1){ 211 while((ch = buf[i++]) != ';' && ch != '{')if(i >= in)goto notc; 212 printf("c program text"); 213 goto outa; 214 } 215 nl = 0; 216 while(buf[i] != '('){ 217 if(buf[i] <= 0) 218 goto notas; 219 if(buf[i] == ';'){ 220 i++; 221 goto check; 222 } 223 if(buf[i++] == '\n') 224 if(nl++ > 6)goto notc; 225 if(i >= in)goto notc; 226 } 227 while(buf[i] != ')'){ 228 if(buf[i++] == '\n') 229 if(nl++ > 6)goto notc; 230 if(i >= in)goto notc; 231 } 232 while(buf[i] != '{'){ 233 if(buf[i++] == '\n') 234 if(nl++ > 6)goto notc; 235 if(i >= in)goto notc; 236 } 237 printf("c program text"); 238 goto outa; 239 notc: 240 i = 0; 241 while(buf[i] == 'c' || buf[i] == '#'){ 242 while(buf[i++] != '\n')if(i >= in)goto notfort; 243 } 244 if(lookup(fort) == 1){ 245 printf("fortran program text"); 246 goto outa; 247 } 248 notfort: 249 i=0; 250 if(ascom() == 0)goto notas; 251 j = i-1; 252 if(buf[i] == '.'){ 253 i++; 254 if(lookup(as) == 1){ 255 printf("assembler program text"); 256 goto outa; 257 } 258 else if(buf[j] == '\n' && isalpha(buf[j+2])){ 259 printf("roff, nroff, or eqn input text"); 260 goto outa; 261 } 262 } 263 while(lookup(asc) == 0){ 264 if(ascom() == 0)goto notas; 265 while(buf[i] != '\n' && buf[i++] != ':') 266 if(i >= in)goto notas; 267 while(buf[i] == '\n' || buf[i] == ' ' || buf[i] == '\t')if(i++ >= in)goto notas; 268 j = i-1; 269 if(buf[i] == '.'){ 270 i++; 271 if(lookup(as) == 1){ 272 printf("assembler program text"); 273 goto outa; 274 } 275 else if(buf[j] == '\n' && isalpha(buf[j+2])){ 276 printf("roff, nroff, or eqn input text"); 277 goto outa; 278 } 279 } 280 } 281 printf("assembler program text"); 282 goto outa; 283 notas: 284 for(i=0; i < in; i++)if(buf[i]&0200){ 285 if (buf[0]=='\100' && buf[1]=='\357') 286 printf("troff (CAT) output\n"); 287 else 288 printf("data\n"); 289 return; 290 } 291 if (mbuf.st_mode&((S_IEXEC)|(S_IEXEC>>3)|(S_IEXEC>>6))) { 292 if (mbuf.st_mode & S_ISUID) 293 printf("set-uid "); 294 if (mbuf.st_mode & S_ISGID) 295 printf("set-gid "); 296 if (mbuf.st_mode & S_ISVTX) 297 printf("sticky "); 298 if (shell(buf, in, sh)) 299 printf("shell script"); 300 else if (shell(buf, in, csh)) 301 printf("c-shell script"); 302 else 303 printf("commands text"); 304 } else if (troffint(buf, in)) 305 printf("troff intermediate output text"); 306 else if (shell(buf, in, sh)) 307 printf("shell commands"); 308 else if (shell(buf, in, csh)) 309 printf("c-shell commands"); 310 else if (english(buf, in)) 311 printf("English text"); 312 else 313 printf("ascii text"); 314 outa: 315 while(i < in) 316 if((buf[i++]&0377) > 127){ 317 printf(" with garbage\n"); 318 return; 319 } 320 /* if next few lines in then read whole file looking for nulls ... 321 while((in = read(ifile,buf,BUFSIZ)) > 0) 322 for(i = 0; i < in; i++) 323 if((buf[i]&0377) > 127){ 324 printf(" with garbage\n"); 325 return; 326 } 327 /*.... */ 328 printf("\n"); 329 } 330 331 oldo(cp) 332 char *cp; 333 { 334 struct exec ex; 335 struct stat stb; 336 337 ex = *(struct exec *)cp; 338 if (fstat(ifile, &stb) < 0) 339 return(0); 340 if (N_STROFF(ex)+sizeof(off_t) > stb.st_size) 341 return (1); 342 return (0); 343 } 344 345 346 347 troffint(bp, n) 348 char *bp; 349 int n; 350 { 351 int k; 352 353 i = 0; 354 for (k = 0; k < 6; k++) { 355 if (lookup(troff) == 0) 356 return(0); 357 if (lookup(troff) == 0) 358 return(0); 359 while (i < n && buf[i] != '\n') 360 i++; 361 if (i++ >= n) 362 return(0); 363 } 364 return(1); 365 } 366 lookup(tab) 367 char *tab[]; 368 { 369 char r; 370 int k,j,l; 371 while(buf[i] == ' ' || buf[i] == '\t' || buf[i] == '\n')i++; 372 for(j=0; tab[j] != 0; j++){ 373 l=0; 374 for(k=i; ((r=tab[j][l++]) == buf[k] && r != '\0');k++); 375 if(r == '\0') 376 if(buf[k] == ' ' || buf[k] == '\n' || buf[k] == '\t' 377 || buf[k] == '{' || buf[k] == '/'){ 378 i=k; 379 return(1); 380 } 381 } 382 return(0); 383 } 384 ccom(){ 385 char cc; 386 while((cc = buf[i]) == ' ' || cc == '\t' || cc == '\n')if(i++ >= in)return(0); 387 if(buf[i] == '/' && buf[i+1] == '*'){ 388 i += 2; 389 while(buf[i] != '*' || buf[i+1] != '/'){ 390 if(buf[i] == '\\')i += 2; 391 else i++; 392 if(i >= in)return(0); 393 } 394 if((i += 2) >= in)return(0); 395 } 396 if(buf[i] == '\n')if(ccom() == 0)return(0); 397 return(1); 398 } 399 ascom(){ 400 while(buf[i] == '/'){ 401 i++; 402 while(buf[i++] != '\n')if(i >= in)return(0); 403 while(buf[i] == '\n')if(i++ >= in)return(0); 404 } 405 return(1); 406 } 407 408 english (bp, n) 409 char *bp; 410 { 411 # define NASC 128 412 int ct[NASC], j, vow, freq, rare; 413 int badpun = 0, punct = 0; 414 if (n<50) return(0); /* no point in statistics on squibs */ 415 for(j=0; j<NASC; j++) 416 ct[j]=0; 417 for(j=0; j<n; j++) 418 { 419 if ((u_char)bp[j]<NASC) 420 ct[bp[j]|040]++; 421 switch (bp[j]) 422 { 423 case '.': 424 case ',': 425 case ')': 426 case '%': 427 case ';': 428 case ':': 429 case '?': 430 punct++; 431 if ( j < n-1 && 432 bp[j+1] != ' ' && 433 bp[j+1] != '\n') 434 badpun++; 435 } 436 } 437 if (badpun*5 > punct) 438 return(0); 439 vow = ct['a'] + ct['e'] + ct['i'] + ct['o'] + ct['u']; 440 freq = ct['e'] + ct['t'] + ct['a'] + ct['i'] + ct['o'] + ct['n']; 441 rare = ct['v'] + ct['j'] + ct['k'] + ct['q'] + ct['x'] + ct['z']; 442 if (2*ct[';'] > ct['e']) return(0); 443 if ( (ct['>']+ct['<']+ct['/'])>ct['e']) return(0); /* shell file test */ 444 return (vow*5 >= n-ct[' '] && freq >= 10*rare); 445 } 446 447 shellscript(buf, sb) 448 char buf[]; 449 struct stat *sb; 450 { 451 register char *tp; 452 char *cp, *xp, *index(); 453 454 cp = index(buf, '\n'); 455 if (cp == 0 || cp - buf > in) 456 return (0); 457 for (tp = buf; tp != cp && isspace(*tp); tp++) 458 if (!isascii(*tp)) 459 return (0); 460 for (xp = tp; tp != cp && !isspace(*tp); tp++) 461 if (!isascii(*tp)) 462 return (0); 463 if (tp == xp) 464 return (0); 465 if (sb->st_mode & S_ISUID) 466 printf("set-uid "); 467 if (sb->st_mode & S_ISGID) 468 printf("set-gid "); 469 if (strncmp(xp, "/bin/sh", tp-xp) == 0) 470 xp = "shell"; 471 else if (strncmp(xp, "/bin/csh", tp-xp) == 0) 472 xp = "c-shell"; 473 else 474 *tp = '\0'; 475 printf("executable %s script\n", xp); 476 return (1); 477 } 478 479 shell(bp, n, tab) 480 char *bp; 481 int n; 482 char *tab[]; 483 { 484 485 i = 0; 486 do { 487 if (buf[i] == '#' || buf[i] == ':') 488 while (i < n && buf[i] != '\n') 489 i++; 490 if (++i >= n) 491 break; 492 if (lookup(tab) == 1) 493 return (1); 494 } while (i < n); 495 return (0); 496 } 497