changeset 7036:a57aa913b52c

* tmpfile-safer.c: New file. * stdio-safer.h (fopen_safer): Add prototype. * stdio--.h (tmpfile): Make safer.
author Eric Blake <ebb9@byu.net>
date Sun, 23 Jul 2006 12:58:15 +0000
parents 264f42792bc8
children cca9b74499c4
files lib/ChangeLog lib/stdio--.h lib/stdio-safer.h lib/tmpfile-safer.c
diffstat 4 files changed, 88 insertions(+), 2 deletions(-) [+]
line wrap: on
line diff
--- a/lib/ChangeLog
+++ b/lib/ChangeLog
@@ -1,3 +1,9 @@
+2006-07-23  Eric Blake  <ebb9@byu.net>
+
+	* tmpfile-safer.c: New file.
+	* stdio-safer.h (fopen_safer): Add prototype.
+	* stdio--.h (tmpfile): Make safer.
+
 2006-07-22  Paul Eggert  <eggert@cs.ucla.edu>
 
 	* close-stream.c, close-stream.h: New files.
--- a/lib/stdio--.h
+++ b/lib/stdio--.h
@@ -1,6 +1,6 @@
 /* Like stdio.h, but redefine some names to avoid glitches.
 
-   Copyright (C) 2005 Free Software Foundation, Inc.
+   Copyright (C) 2005, 2006 Free Software Foundation, Inc.
 
    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
@@ -23,3 +23,6 @@
 
 #undef fopen
 #define fopen fopen_safer
+
+#undef tmpfile
+#define tmpfile tmpfile-safer
--- a/lib/stdio-safer.h
+++ b/lib/stdio-safer.h
@@ -1,6 +1,6 @@
 /* Invoke stdio functions, but avoid some glitches.
 
-   Copyright (C) 2001, 2003 Free Software Foundation, Inc.
+   Copyright (C) 2001, 2003, 2006 Free Software Foundation, Inc.
 
    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
@@ -21,3 +21,4 @@
 #include <stdio.h>
 
 FILE *fopen_safer (char const *, char const *);
+FILE *tmpfile_safer (void);
new file mode 100644
--- /dev/null
+++ b/lib/tmpfile-safer.c
@@ -0,0 +1,76 @@
+/* Invoke tmpfile, but avoid some glitches.
+   Copyright (C) 2006 Free Software Foundation, Inc.
+
+   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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+/* Written by Eric Blake, based on ideas from Paul Eggert.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "stdio-safer.h"
+
+#include <errno.h>
+#include <unistd.h>
+#include "unistd-safer.h"
+
+#include "binary-io.h"
+
+#ifndef STDERR_FILENO
+# define STDERR_FILENO 2
+#endif
+
+/* Like tmpfile, but do not return stdin, stdout, or stderr.
+
+   Remember that tmpfile can leave files behind if your program calls _exit,
+   so this function should not be mixed with the close_stdout module.  */
+
+FILE *
+tmpfile_safer (void)
+{
+  FILE *fp = tmpfile ();
+
+  if (fp)
+    {
+      int fd = fileno (fp);
+
+      if (0 <= fd && fd <= STDERR_FILENO)
+	{
+	  int f = dup_safer (fd);
+
+	  if (f < 0)
+	    {
+	      int e = errno;
+	      fclose (fp);
+	      errno = e;
+	      return NULL;
+	    }
+
+	  /* Keep the temporary file in binary mode, on platforms
+	     where that matters.  */
+	  if (fclose (fp) != 0
+	      || ! (fp = fdopen (f, O_BINARY ? "wb+" : "w+")))
+	    {
+	      int e = errno;
+	      close (f);
+	      errno = e;
+	      return NULL;
+	    }
+	}
+    }
+
+  return fp;
+}