aboutsummaryrefslogtreecommitdiff
path: root/stdio/fopen.c
diff options
context:
space:
mode:
Diffstat (limited to 'stdio/fopen.c')
-rw-r--r--stdio/fopen.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/stdio/fopen.c b/stdio/fopen.c
new file mode 100644
index 0000000000..fba6ac436a
--- /dev/null
+++ b/stdio/fopen.c
@@ -0,0 +1,110 @@
+/* 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 <ctype.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+#define badmode() return ((errno = EINVAL), 0)
+
+/* Dissect the given mode string into an __io_mode. */
+int
+DEFUN(__getmode, (mode, mptr), CONST char *mode AND __io_mode *mptr)
+{
+ register unsigned char i;
+
+ if (mode == NULL)
+ badmode ();
+
+ memset ((PTR) mptr, 0, sizeof (*mptr));
+
+ switch (*mode)
+ {
+ case 'a':
+ mptr->__write = mptr->__create = mptr->__append = 1;
+ break;
+ case 'w':
+ mptr->__write = mptr->__create = mptr->__truncate = 1;
+ break;
+ case 'r':
+ mptr->__read = 1;
+ break;
+ default:
+ badmode ();
+ }
+
+ for (i = 1; i < 3; ++i)
+ {
+ ++mode;
+ if (*mode == '\0')
+ break;
+ switch (*mode)
+ {
+ case '+':
+ mptr->__read = mptr->__write = 1;
+ break;
+ case 'b':
+ mptr->__binary = 1;
+ break;
+ }
+ }
+
+ if (!mptr->__read && !mptr->__write)
+ badmode ();
+
+ mptr->__exclusive = *mode == 'x';
+
+ return 1;
+}
+
+/* Open a new stream on the given file. */
+FILE *
+DEFUN(fopen, (filename, mode), CONST char *filename AND CONST char *mode)
+{
+ FILE *stream;
+ __io_mode m;
+
+ if (filename == NULL)
+ {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ if (!__getmode (mode, &m))
+ return NULL;
+
+ stream = __newstream ();
+ if (stream == NULL)
+ return NULL;
+
+ if (__stdio_open (filename, m, &stream->__cookie))
+ {
+ int save = errno;
+ (void) fclose (stream);
+ errno = save;
+ return NULL;
+ }
+
+ stream->__mode = m;
+
+ return stream;
+}