diff options
Diffstat (limited to 'lib/libc/stdio/fopen.c')
| -rw-r--r-- | lib/libc/stdio/fopen.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/lib/libc/stdio/fopen.c b/lib/libc/stdio/fopen.c new file mode 100644 index 0000000..b08e336 --- /dev/null +++ b/lib/libc/stdio/fopen.c @@ -0,0 +1,97 @@ +/*- + * Copyright (c) 1990, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Chris Torek. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#if defined(LIBC_SCCS) && !defined(lint) +static char sccsid[] = "@(#)fopen.c 8.1 (Berkeley) 6/4/93"; +#endif /* LIBC_SCCS and not lint */ +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include "namespace.h" +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> +#include <stdio.h> +#include <errno.h> +#include <limits.h> +#include "un-namespace.h" + +#include "local.h" + +FILE * +fopen(const char * __restrict file, const char * __restrict mode) +{ + FILE *fp; + int f; + int flags, oflags; + + if ((flags = __sflags(mode, &oflags)) == 0) + return (NULL); + if ((fp = __sfp()) == NULL) + return (NULL); + if ((f = _open(file, oflags, DEFFILEMODE)) < 0) { + fp->_flags = 0; /* release */ + return (NULL); + } + /* + * File descriptors are a full int, but _file is only a short. + * If we get a valid file descriptor that is greater than + * SHRT_MAX, then the fd will get sign-extended into an + * invalid file descriptor. Handle this case by failing the + * open. + */ + if (f > SHRT_MAX) { + fp->_flags = 0; /* release */ + _close(f); + errno = EMFILE; + return (NULL); + } + fp->_file = f; + fp->_flags = flags; + fp->_cookie = fp; + fp->_read = __sread; + fp->_write = __swrite; + fp->_seek = __sseek; + fp->_close = __sclose; + /* + * When opening in append mode, even though we use O_APPEND, + * we need to seek to the end so that ftell() gets the right + * answer. If the user then alters the seek pointer, or + * the file extends, this will fail, but there is not much + * we can do about this. (We could set __SAPP and check in + * fseek and ftell.) + */ + if (oflags & O_APPEND) + (void)_sseek(fp, (fpos_t)0, SEEK_END); + return (fp); +} |
