summaryrefslogtreecommitdiff
path: root/sysdeps/posix/mktemp.c
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/posix/mktemp.c')
-rw-r--r--sysdeps/posix/mktemp.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/sysdeps/posix/mktemp.c b/sysdeps/posix/mktemp.c
new file mode 100644
index 0000000000..c3aae36a7b
--- /dev/null
+++ b/sysdeps/posix/mktemp.c
@@ -0,0 +1,64 @@
+/* Copyright (C) 1991, 1992, 1993 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 Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#include <ansidecl.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+/* Generate a unique temporary file name from TEMPLATE.
+ The last six characters of TEMPLATE must be "XXXXXX";
+ they are replaced with a string that makes the filename unique. */
+char *
+DEFUN(mktemp, (template), char *template)
+{
+ static CONST char letters[]
+ = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
+ size_t len;
+ size_t i;
+
+ len = strlen (template);
+ if (len < 6 || strcmp (&template[len - 6], "XXXXXX"))
+ {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ if (sprintf (&template[len - 5], "%.5u",
+ (unsigned int) getpid () % 100000) != 5)
+ /* Inconceivable lossage. */
+ return NULL;
+
+ for (i = 0; i < sizeof (letters); ++i)
+ {
+ struct stat ignored;
+
+ template[len - 6] = letters[i];
+
+ if (stat (template, &ignored) < 0 && errno == ENOENT)
+ /* The file does not exist. So return this name. */
+ return template;
+ }
+
+ /* We return the null string if we can't find a unique file name. */
+ template[0] = '\0';
+ return template;
+}