Initial release

mediachanger/castorrmc/common/Cdomainname.c

+/*
+ * Copyright (C) 2002 by CERN/IT/DS/HSM
+ * All rights reserved
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)$RCSfile: Cdomainname.c,v $ $Revision: 1.1 $ $Date: 2002/03/14 11:18:42 $ CERN IT-DS/HSM Jean-Philippe Baud";
+#endif /* not lint */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#if defined(_WIN32)
+#include <winsock2.h>
+#else
+#include <netdb.h>
+#include <netinet/in.h>
+#include <sys/socket.h>
+#endif
+#include "Castor_limits.h"
+#include "Cnetdb.h"
+#include "serrno.h"
+
+/* Cdomainname - get domain name */
+
+int DLL_DECL Cdomainname(char *name, int namelen)
+{
+	char hostname[CA_MAXHOSTNAMELEN+1];
+	struct hostent *hp;
+	char *p;
+
+#ifndef _WIN32
+	FILE *fd;
+	/*
+	 * try looking in /etc/resolv.conf
+	 * putting this here and assuming that it is correct, eliminates
+	 * calls to gethostbyname, and therefore DNS lookups. This helps
+	 * those on dialup systems.
+	 */
+	if ((fd = fopen ("/etc/resolv.conf", "r")) != NULL) {
+		char line[300];
+		while (fgets (line, sizeof(line), fd) != NULL) {
+			if ((strncmp (line, "domain", 6) == 0 ||
+			    strncmp (line, "search", 6) == 0) && line[6] == ' ') {
+				p = line + 6;
+				while (*p == ' ')
+					p++;
+				if (*p)
+					*(p + strlen (p) - 1) = '\0';
+				if (sizeof (p) > namelen) {
+					serrno = EINVAL;
+					return (-1);
+				}
+				strcpy (name, p);
+				return (0);
+			}
+		}
+		fclose(fd);
+	}
+#endif
+
+	/* Try gethostname */
+
+	gethostname (hostname, CA_MAXHOSTNAMELEN+1);
+
+	if (hp = Cgethostbyname (hostname)) {
+		struct in_addr *haddrarray;
+		struct in_addr **haddrlist;
+		struct hostent *hp2;
+		int i;
+		int naddr = 0;
+
+		/* need to save list (at least on Digital Unix) */
+
+		haddrlist = (struct in_addr **)hp->h_addr_list;
+		while (*haddrlist) {
+			naddr++;
+			haddrlist++;
+		}
+		if ((haddrarray = (struct in_addr *) malloc (naddr * sizeof(struct in_addr))) == NULL) {
+			serrno = ENOMEM;
+			return (-1);
+		}
+		haddrlist = (struct in_addr **)hp->h_addr_list;
+		for (i = 0; i < naddr; i++) {
+			memcpy (haddrarray + i, *haddrlist, sizeof(struct in_addr));
+			haddrlist++;
+		}
+
+		for (i = 0; i < naddr; i++) {
+			if (hp2 = Cgethostbyaddr (haddrarray + i,
+			    sizeof(struct in_addr), AF_INET)) {
+				char **hal;
+				if (p = strchr (hp2->h_name, '.')) {
+					free (haddrarray);
+					p++;
+					if (sizeof (p) > namelen) {
+						serrno = EINVAL;
+						return (-1);
+					}
+					strcpy (name, p);
+					return (0);
+				}
+
+				/* Look for aliases */
+
+				hal = hp2->h_aliases;
+				while (*hal) {
+					if (p = strchr (*hal, '.')) {
+						free (haddrarray);
+						p++;
+						if (sizeof (p) > namelen) {
+							serrno = EINVAL;
+							return (-1);
+						}
+						strcpy (name, p);
+						return (0);
+					}
+					hal++;
+				}
+				printf("end of list\n");
+			}
+		}
+		free (haddrarray);
+	}
+	serrno = SEINTERNAL;
+	return (-1);
+}