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author | Gregory Nutt <gnutt@nuttx.org> | 2014-11-29 10:53:22 -0600 |
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committer | Gregory Nutt <gnutt@nuttx.org> | 2014-11-29 10:53:22 -0600 |
commit | 6fa66b5a77300b73f40dbaae2bb831d92eaa8fe6 (patch) | |
tree | 64046c058f5f6e86d9f59dee44f9b6faba15d4cf /nuttx/libc/misc/lib_ioctl.c | |
parent | 7773304d911066ca3345eb295a944d949fd220c4 (diff) | |
download | px4-nuttx-6fa66b5a77300b73f40dbaae2bb831d92eaa8fe6.tar.gz px4-nuttx-6fa66b5a77300b73f40dbaae2bb831d92eaa8fe6.tar.bz2 px4-nuttx-6fa66b5a77300b73f40dbaae2bb831d92eaa8fe6.zip |
Add support for a variadic ioctl() function. The ioctl() interface is a non-standard, Unix interface. NuttX has always used the older, three-parameter version. Most contemporary systems now, however, use a variadic form of the ioctl() function. Added an option to insert a shim layer to adapt the three-parameter ioctl() to use the variadic interface form. Internally, the ioctl handling is the same three-parameter logic. The only real complexity to the shim is in how the system calls must be handled.
Diffstat (limited to 'nuttx/libc/misc/lib_ioctl.c')
-rw-r--r-- | nuttx/libc/misc/lib_ioctl.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/nuttx/libc/misc/lib_ioctl.c b/nuttx/libc/misc/lib_ioctl.c new file mode 100644 index 000000000..9ef09fcd9 --- /dev/null +++ b/nuttx/libc/misc/lib_ioctl.c @@ -0,0 +1,101 @@ +/**************************************************************************** + * libc/misc/lib_ioctl.c + * + * Copyright (C) 2014 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <gnutt@nuttx.org> + * + * 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 NuttX 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 COPYRIGHT HOLDERS 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 + * COPYRIGHT OWNER 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. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> + +#include <sys/ioctl.h> +#include <stdarg.h> +#include <errno.h> + +#include <nuttx/fs/fs.h> + +#include "lib_internal.h" + +#if defined(CONFIG_LIBC_IOCTL_VARIADIC) && CONFIG_NFILE_DESCRIPTORS > 0 + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: ioctl/fs_ioctl + * + * Description: + * Perform device specific operations. + * + * Parameters: + * fd File/socket descriptor of device + * req The ioctl command + * ... One argument of type unsigned long is expected + * + * Return: + * >=0 on success (positive non-zero values are cmd-specific) + * -1 on failure withi errno set properly: + * + * EBADF + * 'fd' is not a valid descriptor. + * EFAULT + * 'arg' references an inaccessible memory area. + * EINVAL + * 'cmd' or 'arg' is not valid. + * ENOTTY + * 'fd' is not associated with a character special device. + * ENOTTY + * The specified request does not apply to the kind of object that the + * descriptor 'fd' references. + * + ****************************************************************************/ + +int ioctl(int fd, int req, ...) +{ + va_list ap; + unsigned long arg; + + /* Get the unsigned long argument */ + + va_start(ap, req); + arg = va_arg(ap, unsigned long ); + va_end(ap); + + /* Then let fs_ioctl() to the real work */ + + return fs_ioctl(fd, req, arg); +} + +#endif /* CONFIG_LIBC_IOCTL_VARIADIC && CONFIG_NFILE_DESCRIPTORS > 0 */ |