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Diffstat (limited to 'REORG.TODO/sysdeps/unix/sysv/linux/gethostid.c')
-rw-r--r--REORG.TODO/sysdeps/unix/sysv/linux/gethostid.c118
1 files changed, 118 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/gethostid.c b/REORG.TODO/sysdeps/unix/sysv/linux/gethostid.c
new file mode 100644
index 0000000000..cc108aa2d6
--- /dev/null
+++ b/REORG.TODO/sysdeps/unix/sysv/linux/gethostid.c
@@ -0,0 +1,118 @@
+/* Copyright (C) 1995-2017 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <alloca.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <netdb.h>
+#include <not-cancel.h>
+
+#define HOSTIDFILE "/etc/hostid"
+
+#ifdef SET_PROCEDURE
+int
+sethostid (long int id)
+{
+ int fd;
+ ssize_t written;
+ int32_t id32 = id;
+
+ /* Test for appropriate rights to set host ID. */
+ if (__libc_enable_secure)
+ {
+ __set_errno (EPERM);
+ return -1;
+ }
+
+ /* Make sure the ID is not too large. Needed for bi-arch support. */
+ if (id32 != id)
+ {
+ __set_errno (EOVERFLOW);
+ return -1;
+ }
+
+ /* Open file for writing. Everybody is allowed to read this file. */
+ fd = open_not_cancel (HOSTIDFILE, O_CREAT|O_WRONLY|O_TRUNC, 0644);
+ if (fd < 0)
+ return -1;
+
+ written = write_not_cancel (fd, &id32, sizeof (id32));
+
+ close_not_cancel_no_status (fd);
+
+ return written != sizeof (id32) ? -1 : 0;
+}
+
+#else
+# include <string.h>
+# include <sys/param.h>
+# include <resolv/netdb.h>
+# include <netinet/in.h>
+
+long int
+gethostid (void)
+{
+ char hostname[MAXHOSTNAMELEN + 1];
+ size_t buflen;
+ char *buffer;
+ struct hostent hostbuf, *hp;
+ int32_t id;
+ struct in_addr in;
+ int herr;
+ int fd;
+
+ /* First try to get the ID from a former invocation of sethostid. */
+ fd = open_not_cancel (HOSTIDFILE, O_RDONLY|O_LARGEFILE, 0);
+ if (fd >= 0)
+ {
+ ssize_t n = read_not_cancel (fd, &id, sizeof (id));
+
+ close_not_cancel_no_status (fd);
+
+ if (n == sizeof (id))
+ return id;
+ }
+
+ /* Getting from the file was not successful. An intelligent guess for
+ a unique number of a host is its IP address. Return this. */
+ if (__gethostname (hostname, MAXHOSTNAMELEN) < 0 || hostname[0] == '\0')
+ /* This also fails. Return and arbitrary value. */
+ return 0;
+
+ buflen = 1024;
+ buffer = __alloca (buflen);
+
+ /* To get the IP address we need to know the host name. */
+ while (__gethostbyname_r (hostname, &hostbuf, buffer, buflen, &hp, &herr)
+ != 0
+ || hp == NULL)
+ if (herr != NETDB_INTERNAL || errno != ERANGE)
+ return 0;
+ else
+ /* Enlarge buffer. */
+ buffer = extend_alloca (buffer, buflen, 2 * buflen);
+
+ in.s_addr = 0;
+ memcpy (&in, hp->h_addr,
+ (int) sizeof (in) < hp->h_length ? (int) sizeof (in) : hp->h_length);
+
+ /* For the return value to be not exactly the IP address we do some
+ bit fiddling. */
+ return (int32_t) (in.s_addr << 16 | in.s_addr >> 16);
+}
+#endif