1 /*- 2 * Copyright (c) 1998 Dag-Erling Co�dan Sm�rgrav 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer 10 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software withough specific prior written permission 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * $Id$ 29 */ 30 31 static const char CVSID[] = "$Id$"; 32 33 #include <err.h> 34 #include <ctype.h> 35 #include <stdio.h> 36 #include <stdlib.h> 37 #include <string.h> 38 #include <sysexits.h> 39 40 extern char *__progname; 41 42 void 43 usage(void) 44 { 45 fprintf(stderr, "usage: %s [groupfile]\n", __progname); 46 exit(EX_USAGE); 47 } 48 49 int 50 main(int argc, char *argv[]) 51 { 52 unsigned int len; 53 int n = 0, i, k, e = 0; 54 char *gfn, *line, *f[4], *p; 55 FILE *gf; 56 57 /* check arguments */ 58 switch (argc) { 59 case 1: 60 gfn = "/etc/group"; 61 break; 62 case 2: 63 gfn = argv[1]; 64 break; 65 default: 66 gfn = NULL; /* silence compiler */ 67 usage(); 68 } 69 70 /* open group file */ 71 if ((gf = fopen(gfn, "r")) == NULL) 72 err(EX_IOERR, gfn); /* XXX - is IO_ERR the correct exit code? */ 73 74 /* check line by line */ 75 while (++n) { 76 if ((line = fgetln(gf, &len)) == NULL) 77 break; 78 while (len && isspace(line[len-1])) 79 len--; 80 81 /* ignore blank lines and comments */ 82 for (p = line; p < (line + len); p++) 83 if (!isspace(*p)) break; 84 if (!len || (*p == '#')) { 85 #if 0 86 /* entry is correct, so print it */ 87 printf("%*.*s\n", len, len, line); 88 #endif 89 continue; 90 } 91 92 /* 93 * A correct group entry has four colon-separated fields, the third 94 * of which must be entirely numeric and the fourth of which may 95 * be empty. 96 */ 97 for (i = k = 0; k < 4; k++) { 98 for (f[k] = line+i; (i < len) && (line[i] != ':'); i++) 99 /* nothing */ ; 100 if ((k < 3) && (line[i] != ':')) 101 break; 102 line[i++] = 0; 103 } 104 if (k < 4) { 105 warnx("%s: line %d: missing field(s)", gfn, n); 106 e++; 107 continue; 108 } 109 110 /* check if fourth field ended with a colon */ 111 if (i < len) { 112 warnx("%s: line %d: too many fields", gfn, n); 113 e++; 114 continue; 115 } 116 117 /* check that none of the fields contain whitespace */ 118 for (k = 0; k < 4; k++) 119 if (strcspn(f[k], " \t") != strlen(f[k])) 120 warnx("%s: line %d: field %d contains whitespace", 121 gfn, n, k+1); 122 123 /* check that the GID is numeric */ 124 if (strspn(f[2], "0123456789") != strlen(f[2])) { 125 warnx("%s: line %d: GID is not numeric", gfn, n); 126 e++; 127 continue; 128 } 129 130 #if 0 131 /* entry is correct, so print it */ 132 printf("%s:%s:%s:%s\n", f[0], f[1], f[2], f[3]); 133 #endif 134 } 135 136 /* check what broke the loop */ 137 if (ferror(gf)) 138 err(EX_IOERR, "%s: line %d", gfn, n); 139 140 /* done */ 141 fclose(gf); 142 exit(e ? EX_DATAERR : EX_OK); 143 } 144