diff options
Diffstat (limited to 'stdio/fopen.c')
-rw-r--r-- | stdio/fopen.c | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/stdio/fopen.c b/stdio/fopen.c new file mode 100644 index 0000000..fba6ac4 --- /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; +} |