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-rw-r--r--libshouldbeinlibc/localhost.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/libshouldbeinlibc/localhost.c b/libshouldbeinlibc/localhost.c
new file mode 100644
index 00000000..f0c67541
--- /dev/null
+++ b/libshouldbeinlibc/localhost.c
@@ -0,0 +1,66 @@
+/* A slightly more convenient wrapper for gethostname
+
+ Copyright (C) 1996 Free Software Foundation, Inc.
+
+ Written by Miles Bader <miles@gnu.ai.mit.edu>
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2, or (at
+ your option) any later version.
+
+ This program 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#include <unistd.h>
+#include <malloc.h>
+#include <string.h>
+#include <errno.h>
+
+/* Return the name of the localhost. This is just a wrapper for gethostname,
+ which takes care of allocating a big enough buffer, and caches the result
+ after the first call (so the result should be copied before modification).
+ If something goes wrong, 0 is returned, and errno set. */
+char *
+localhost ()
+{
+ static char *buf = 0;
+ static size_t buf_len = 0;
+
+ if (! buf)
+ {
+ do {
+ errno = 0;
+
+ if (buf) {
+ buf_len += buf_len;
+ buf = realloc (buf, buf_len);
+ } else {
+ buf_len = 128; /* Initial guess */
+ buf = malloc (buf_len);
+ }
+
+ if (! buf)
+ {
+ errno = ENOMEM;
+ return 0;
+ }
+ } while ((gethostname(buf, buf_len) == 0 && !memchr (buf, '\0', buf_len))
+ || errno == ENAMETOOLONG);
+
+ if (errno)
+ /* gethostname failed, abort. */
+ {
+ free (buf);
+ buf = 0;
+ }
+ }
+
+ return buf;
+}