diff options
Diffstat (limited to 'nuttx/fs/fs_fcntl.c')
| -rw-r--r-- | nuttx/fs/fs_fcntl.c | 264 |
1 files changed, 264 insertions, 0 deletions
diff --git a/nuttx/fs/fs_fcntl.c b/nuttx/fs/fs_fcntl.c new file mode 100644 index 000000000..ff53b0f20 --- /dev/null +++ b/nuttx/fs/fs_fcntl.c @@ -0,0 +1,264 @@ +/**************************************************************************** + * fs/fs_fcntl.c + * + * Copyright (C) 2009, 2012 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 <stdarg.h> +#include <fcntl.h> +#include <errno.h> + +#include <nuttx/fs/fs.h> +#include <nuttx/net/net.h> +#include <nuttx/sched.h> + +#include "fs_internal.h" + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: file_vfcntl + ****************************************************************************/ + +#if CONFIG_NFILE_DESCRIPTORS > 0 +static inline int file_vfcntl(int fildes, int cmd, va_list ap) +{ + FAR struct filelist *list; + FAR struct file *this_file; + int err = 0; + int ret = OK; + + /* Get the thread-specific file list */ + + list = sched_getfiles(); + if (!list) + { + err = EMFILE; + goto errout; + } + + /* Was this file opened ? */ + + this_file = &list->fl_files[fildes]; + if (!this_file->f_inode) + { + err = EBADF; + goto errout; + } + + switch (cmd) + { + case F_DUPFD: + /* Return a new file descriptor which shall be the lowest numbered + * available (that is, not already open) file descriptor greater than + * or equal to the third argument, arg, taken as an integer of type + * int. The new file descriptor shall refer to the same open file + * description as the original file descriptor, and shall share any + * locks. The FD_CLOEXEC flag associated with the new file descriptor + * shall be cleared to keep the file open across calls to one of the + * exec functions. + */ + + { + ret = file_dup(fildes, va_arg(ap, int)); + } + break; + + case F_GETFD: + /* Get the file descriptor flags defined in <fcntl.h> that are associated + * with the file descriptor fildes. File descriptor flags are associated + * with a single file descriptor and do not affect other file descriptors + * that refer to the same file. + */ + + case F_SETFD: + /* Set the file descriptor flags defined in <fcntl.h>, that are associated + * with fildes, to the third argument, arg, taken as type int. If the + * FD_CLOEXEC flag in the third argument is 0, the file shall remain open + * across the exec functions; otherwise, the file shall be closed upon + * successful execution of one of the exec functions. + */ + + err = ENOSYS; + break; + + case F_GETFL: + /* Get the file status flags and file access modes, defined in <fcntl.h>, + * for the file description associated with fildes. The file access modes + * can be extracted from the return value using the mask O_ACCMODE, which is + * defined in <fcntl.h>. File status flags and file access modes are associated + * with the file description and do not affect other file descriptors that + * refer to the same file with different open file descriptions. + */ + + { + ret = this_file->f_oflags; + } + break; + + case F_SETFL: + /* Set the file status flags, defined in <fcntl.h>, for the file description + * associated with fildes from the corresponding bits in the third argument, + * arg, taken as type int. Bits corresponding to the file access mode and + * the file creation flags, as defined in <fcntl.h>, that are set in arg shall + * be ignored. If any bits in arg other than those mentioned here are changed + * by the application, the result is unspecified. + */ + + { + this_file->f_oflags = va_arg(ap, int); + } + break; + + case F_GETOWN: + /* If fildes refers to a socket, get the process or process group ID specified + * to receive SIGURG signals when out-of-band data is available. Positive values + * indicate a process ID; negative values, other than -1, indicate a process group + * ID. If fildes does not refer to a socket, the results are unspecified. + */ + + case F_SETOWN: + /* If fildes refers to a socket, set the process or process group ID specified + * to receive SIGURG signals when out-of-band data is available, using the value + * of the third argument, arg, taken as type int. Positive values indicate a + * process ID; negative values, other than -1, indicate a process group ID. If + * fildes does not refer to a socket, the results are unspecified. + */ + + err = EBADF; /* Only valid on socket descriptors */ + break; + + case F_GETLK: + /* Get the first lock which blocks the lock description pointed to by the third + * argument, arg, taken as a pointer to type struct flock, defined in <fcntl.h>. + * The information retrieved shall overwrite the information passed to fcntl() in + * the structure flock. If no lock is found that would prevent this lock from being + * created, then the structure shall be left unchanged except for the lock type + * which shall be set to F_UNLCK. + */ + + case F_SETLK: + /* Set or clear a file segment lock according to the lock description pointed to + * by the third argument, arg, taken as a pointer to type struct flock, defined in + * <fcntl.h>. F_SETLK can establish shared (or read) locks (F_RDLCK) or exclusive + * (or write) locks (F_WRLCK), as well as to remove either type of lock (F_UNLCK). + * F_RDLCK, F_WRLCK, and F_UNLCK are defined in <fcntl.h>. If a shared or exclusive + * lock cannot be set, fcntl() shall return immediately with a return value of -1. + */ + + case F_SETLKW: + /* This command shall be equivalent to F_SETLK except that if a shared or exclusive + * lock is blocked by other locks, the thread shall wait until the request can be + * satisfied. If a signal that is to be caught is received while fcntl() is waiting + * for a region, fcntl() shall be interrupted. Upon return from the signal handler, + * fcntl() shall return -1 with errno set to [EINTR], and the lock operation shall + * not be done. + */ + + err = ENOSYS; /* Not implemented */ + break; + + default: + err = EINVAL; + break; + } + +errout: + if (err != 0) + { + set_errno(err); + return ERROR; + } + + return ret; +} +#endif /* CONFIG_NFILE_DESCRIPTORS > 0 */ + +/**************************************************************************** + * Global Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: fcntl + ****************************************************************************/ + +int fcntl(int fildes, int cmd, ...) +{ + va_list ap; + int ret; + + /* Setup to access the variable argument list */ + + va_start(ap, cmd); + + /* Did we get a valid file descriptor? */ + +#if CONFIG_NFILE_DESCRIPTORS > 0 + if ((unsigned int)fildes < CONFIG_NFILE_DESCRIPTORS) + { + /* Yes.. defer file operations to file_vfcntl() */ + + ret = file_vfcntl(fildes, cmd, ap); + } + else +#endif + { + /* No... check for operations on a socket descriptor */ + +#if defined(CONFIG_NET) && CONFIG_NSOCKET_DESCRIPTORS > 0 + if ((unsigned int)fildes < (CONFIG_NFILE_DESCRIPTORS+CONFIG_NSOCKET_DESCRIPTORS)) + { + /* Yes.. defer socket descriptor operations to net_vfcntl() */ + + ret = net_vfcntl(fildes, cmd, ap); + } + else +#endif + { + /* No.. this descriptor number is out of range */ + + ret = EBADF; + } + } + + va_end(ap); + return ret; +} + |