static char sccsid[] = "@(#)file.c 4.4 (Berkeley) 4.4"; /* * file - determine type of file */ #include #include #include #include #include #include int in; int i = 0; char buf[BUFSIZ]; char *troff[] = { /* new troff intermediate lang */ "x","T","res","init","font","202","V0","p1",0}; char *fort[] = { "function","subroutine","common","dimension","block","integer", "real","data","double",0}; char *asc[] = { "chmk","mov","tst","clr","jmp",0}; char *c[] = { "int","char","float","double","struct","extern",0}; char *as[] = { "globl","byte","align","text","data","comm",0}; int ifile; main(argc, argv) char **argv; { FILE *fl; register char *p; char ap[128]; extern char _sobuf[]; if (argc>1 && argv[1][0]=='-' && argv[1][1]=='f') { if ((fl = fopen(argv[2], "r")) == NULL) { printf("Can't open %s\n", argv[2]); exit(2); } while ((p = fgets(ap, 128, fl)) != NULL) { int l = strlen(p); if (l>0) p[l-1] = '\0'; printf("%s: ", p); type(p); if (ifile>=0) close(ifile); } exit(1); } while(argc > 1) { printf("%s: ", argv[1]); type(argv[1]); fflush(stdout); argc--; argv++; if (ifile >= 0) close(ifile); } } type(file) char *file; { int j,nl; char ch; struct stat mbuf; ifile = -1; if (lstat(file, &mbuf) < 0) { printf("cannot stat\n"); return; } switch (mbuf.st_mode & S_IFMT) { case S_IFCHR: printf("character"); goto spcl; case S_IFLNK: printf("symbolic link\n"); return; case S_IFDIR: printf("directory\n"); return; case S_IFBLK: printf("block"); spcl: printf(" special (%d/%d)\n", major(mbuf.st_rdev), minor(mbuf.st_rdev)); return; } ifile = open(file, 0); if(ifile < 0) { printf("cannot open\n"); return; } in = read(ifile, buf, BUFSIZ); if(in == 0){ printf("empty\n"); return; } switch(*(int *)buf) { case 0413: printf("demand paged "); case 0410: printf("pure "); goto exec; case 0411: printf("jfr or pdp-11 unix 411 executable\n"); return; case 0407: exec: printf("executable"); if(((int *)buf)[4] != 0) { printf(" not stripped"); if(oldo(buf)) printf(" (old format symbol table)"); } printf("\n"); goto out; case 0177555: printf("very old archive\n"); goto out; case 0177545: printf("old archive\n"); goto out; case 070707: printf("cpio data\n"); goto out; } if(strncmp(buf, "!\n__.SYMDEF", 17) == 0 ) { printf("archive random library\n"); goto out; } if (strncmp(buf, "!\n", 8)==0) { printf("archive\n"); goto out; } if (mbuf.st_size % 512 == 0) { /* it may be a PRESS file */ lseek(ifile, -512L, 2); /* last block */ if (read(ifile, buf, BUFSIZ) > 0 && *(short int *)buf == 12138) { printf("PRESS file\n"); goto out; } } i = 0; if(ccom() == 0)goto notc; while(buf[i] == '#'){ j = i; while(buf[i++] != '\n'){ if(i - j > 255){ printf("data\n"); goto out; } if(i >= in)goto notc; } if(ccom() == 0)goto notc; } check: if(lookup(c) == 1){ while((ch = buf[i++]) != ';' && ch != '{')if(i >= in)goto notc; printf("c program text"); goto outa; } nl = 0; while(buf[i] != '('){ if(buf[i] <= 0) goto notas; if(buf[i] == ';'){ i++; goto check; } if(buf[i++] == '\n') if(nl++ > 6)goto notc; if(i >= in)goto notc; } while(buf[i] != ')'){ if(buf[i++] == '\n') if(nl++ > 6)goto notc; if(i >= in)goto notc; } while(buf[i] != '{'){ if(buf[i++] == '\n') if(nl++ > 6)goto notc; if(i >= in)goto notc; } printf("c program text"); goto outa; notc: i = 0; while(buf[i] == 'c' || buf[i] == '#'){ while(buf[i++] != '\n')if(i >= in)goto notfort; } if(lookup(fort) == 1){ printf("fortran program text"); goto outa; } notfort: i=0; if(ascom() == 0)goto notas; j = i-1; if(buf[i] == '.'){ i++; if(lookup(as) == 1){ printf("assembler program text"); goto outa; } else if(buf[j] == '\n' && isalpha(buf[j+2])){ printf("roff, nroff, or eqn input text"); goto outa; } } while(lookup(asc) == 0){ if(ascom() == 0)goto notas; while(buf[i] != '\n' && buf[i++] != ':') if(i >= in)goto notas; while(buf[i] == '\n' || buf[i] == ' ' || buf[i] == '\t')if(i++ >= in)goto notas; j = i-1; if(buf[i] == '.'){ i++; if(lookup(as) == 1){ printf("assembler program text"); goto outa; } else if(buf[j] == '\n' && isalpha(buf[j+2])){ printf("roff, nroff, or eqn input text"); goto outa; } } } printf("assembler program text"); goto outa; notas: for(i=0; i < in; i++)if(buf[i]&0200){ if (buf[0]=='\100' && buf[1]=='\357') { printf("troff (CAT) output\n"); goto out; } printf("data\n"); goto out; } if (mbuf.st_mode&((S_IEXEC)|(S_IEXEC>>3)|(S_IEXEC>>6))) printf("commands text"); else if (troffint(buf, in)) printf("troff intermediate output text"); else if (english(buf, in)) printf("English text"); else printf("ascii text"); outa: while(i < in) if((buf[i++]&0377) > 127){ printf(" with garbage\n"); goto out; } /* if next few lines in then read whole file looking for nulls ... while((in = read(ifile,buf,BUFSIZ)) > 0) for(i = 0; i < in; i++) if((buf[i]&0377) > 127){ printf(" with garbage\n"); goto out; } /*.... */ printf("\n"); out:; } oldo(cp) char *cp; { struct exec ex; struct stat stb; ex = *(struct exec *)cp; if (fstat(ifile, &stb) < 0) return(0); if (N_STROFF(ex)+sizeof(off_t) > stb.st_size) return (1); return (0); } troffint(bp, n) char *bp; int n; { int k; i = 0; for (k = 0; k < 6; k++) { if (lookup(troff) == 0) return(0); if (lookup(troff) == 0) return(0); while (i < n && buf[i] != '\n') i++; if (i++ >= n) return(0); } return(1); } lookup(tab) char *tab[]; { char r; int k,j,l; while(buf[i] == ' ' || buf[i] == '\t' || buf[i] == '\n')i++; for(j=0; tab[j] != 0; j++){ l=0; for(k=i; ((r=tab[j][l++]) == buf[k] && r != '\0');k++); if(r == '\0') if(buf[k] == ' ' || buf[k] == '\n' || buf[k] == '\t' || buf[k] == '{' || buf[k] == '/'){ i=k; return(1); } } return(0); } ccom(){ char cc; while((cc = buf[i]) == ' ' || cc == '\t' || cc == '\n')if(i++ >= in)return(0); if(buf[i] == '/' && buf[i+1] == '*'){ i += 2; while(buf[i] != '*' || buf[i+1] != '/'){ if(buf[i] == '\\')i += 2; else i++; if(i >= in)return(0); } if((i += 2) >= in)return(0); } if(buf[i] == '\n')if(ccom() == 0)return(0); return(1); } ascom(){ while(buf[i] == '/'){ i++; while(buf[i++] != '\n')if(i >= in)return(0); while(buf[i] == '\n')if(i++ >= in)return(0); } return(1); } english (bp, n) char *bp; { # define NASC 128 int ct[NASC], j, vow, freq, rare; int badpun = 0, punct = 0; if (n<50) return(0); /* no point in statistics on squibs */ for(j=0; j punct) return(0); vow = ct['a'] + ct['e'] + ct['i'] + ct['o'] + ct['u']; freq = ct['e'] + ct['t'] + ct['a'] + ct['i'] + ct['o'] + ct['n']; rare = ct['v'] + ct['j'] + ct['k'] + ct['q'] + ct['x'] + ct['z']; if (2*ct[';'] > ct['e']) return(0); if ( (ct['>']+ct['<']+ct['/'])>ct['e']) return(0); /* shell file test */ return (vow*5 >= n-ct[' '] && freq >= 10*rare); }