Add chkgrp, a small utility for checking for syntax errors in group

files.

PR:		bin/1387
Suggested-by:	Giles Lean <giles@nemeton.com

1 files changed, 143 insertions, 0 deletions

diff --git a/usr.sbin/chkgrp/chkgrp.c b/usr.sbin/chkgrp/chkgrp.c
new file mode 100644
index 0000000..01a87d7
--- /dev/null
+++ b/usr.sbin/chkgrp/chkgrp.c
@@ -0,0 +1,143 @@
+/*-
+ * Copyright (c) 1998 Dag-Erling Coïdan Smørgrav
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software withough specific prior written permission
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *	$Id$
+ */
+
+static const char CVSID[] = "$Id$";
+
+#include <err.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sysexits.h>
+
+extern char *__progname;
+
+void
+usage(void)
+{
+    fprintf(stderr, "usage: %s [groupfile]\n", __progname);
+    exit(EX_USAGE);
+}
+
+int
+main(int argc, char *argv[])
+{
+    unsigned int len;
+    int n = 0, i, k, e = 0;
+    char *gfn, *line, *f[4], *p;
+    FILE *gf;
+
+    /* check arguments */
+    switch (argc) {
+    case 1:
+	gfn = "/etc/group";
+	break;
+    case 2:
+	gfn = argv[1];
+	break;
+    default:
+	gfn = NULL; /* silence compiler */
+	usage();
+    }
+
+    /* open group file */
+    if ((gf = fopen(gfn, "r")) == NULL)
+	err(EX_IOERR, gfn); /* XXX - is IO_ERR the correct exit code? */
+
+    /* check line by line */
+    while (++n) {
+	if ((line = fgetln(gf, &len)) == NULL)
+	    break;
+	while (len && isspace(line[len-1]))
+	    len--;
+
+	/* ignore blank lines and comments */
+	for (p = line; p < (line + len); p++)
+	    if (!isspace(*p)) break;
+	if (!len || (*p == '#')) {
+#if 0
+	    /* entry is correct, so print it */
+	    printf("%*.*s\n", len, len, line);
+#endif
+	    continue;
+	}
+	
+	/*
+	 * A correct group entry has four colon-separated fields, the third
+	 * of which must be entirely numeric and the fourth of which may
+	 * be empty.
+	 */
+	for (i = k = 0; k < 4; k++) {
+	    for (f[k] = line+i; (i < len) && (line[i] != ':'); i++)
+		/* nothing */ ;
+	    if ((k < 3) && (line[i] != ':'))
+		break;
+	    line[i++] = 0;
+	}
+	if (k < 4) {
+	    warnx("%s: line %d: missing field(s)", gfn, n);
+	    e++;
+	    continue;
+	}
+
+	/* check if fourth field ended with a colon */
+	if (i < len) {
+	    warnx("%s: line %d: too many fields", gfn, n);
+	    e++;
+	    continue;
+	}
+	
+	/* check that none of the fields contain whitespace */
+	for (k = 0; k < 4; k++)
+	    if (strcspn(f[k], " \t") != strlen(f[k]))
+		warnx("%s: line %d: field %d contains whitespace",
+		      gfn, n, k+1);
+
+	/* check that the GID is numeric */
+	if (strspn(f[2], "0123456789") != strlen(f[2])) {
+	    warnx("%s: line %d: GID is not numeric", gfn, n);
+	    e++;
+	    continue;
+	}
+	
+#if 0
+	/* entry is correct, so print it */
+	printf("%s:%s:%s:%s\n", f[0], f[1], f[2], f[3]);
+#endif	
+    }
+
+    /* check what broke the loop */
+    if (ferror(gf))
+	err(EX_IOERR, "%s: line %d", gfn, n);
+
+    /* done */
+    fclose(gf);
+    exit(e ? EX_DATAERR : EX_OK);
+}