FAT. Effectively handles the situation when a new file position is within the current sector.
* Find begin of the next token
* EOL
* revert
* Accelerates the work of the FS with a multitude of operations to write small pieces of data within the current sector.
Approved-by: Gregory Nutt <gnutt@nuttx.org>
Squashed commit of the following:
fs/fat: Resolves issues with truncating the cluster chain when shrinking files via ftruncate().
fs/fat: First cut at implementation file shrinkage logic needed to support ftruncate(). Certainly shrinks the file size but it does not appear to correctly disconnect the cluster chains.
fs/fat: Restructure some functions in files to better support forthcoming file shrinkage logic. Put framework for file shrinkage in place. That logic is incomplete on initial commit.
fs/nxffs: Add partial implementation of the truncate method: It extend files, but cannot yet shrink them.
fs/smartfs: Add partial implementation of the truncate method: It extend files, but cannot yet shrink them.
fs/fat: Add partial implementation of the truncate method: It extend files, but no yet shrink them.
fs/nfs: Add support for the truncate method to the NFS file system.
fs: Add truncate() support for userfs
fs/unionfs: Add truncate() support to the unionfs
fs/tmpfs: Add ftruncate() support to tmpfs
syscall/: Add system call support for ftruncate()
net/route: Adding ftruncate() support eliminates an issue in file-based routing table management.
fs: Add basic framework to support truncate() and ftruncate(). The infrastructure is complete. Now, however, the actual implementation of ftruncate() will have to be done for each file system.
This conversion is unfortunate in the sense that Unix local domain sockets are relatively lightweight. LocalHost UDP sockets are much heavier weight since they rely on the full UDP stack. If anyone is up for a complete redesign, then using some shared memory and a POSIX message queue would be lightweight again.
This commit also fixes several bugs that were not testable before the inode tree deadlock. I cannot say that the logic is 100% stable but it does not have basic functionality.
Squashed commit of the following:
fs/userfs: Order locking so that access to the shared I/O buffer is also locked.
fs/userfs: Converts to use LocalHost UDP loopback for IPC.
fs/userfs: This completes coding of the UserFS client and of the UserFS feature in general. This feature is being merged to main now because I believe it is innocuous. It is, however, untesed. The next step will be to develop a test case to verify the feature.
fs/userfs: Completes the request logic for the UserFS client. Still need the logic that receives the responses.
fs/userfs: Completes coding for most of the server side of the user filesystem logic.
fs/userfs: Big design changes, simplications. Use Unix domain local sockets instead of message queues. Easier to transfer big data in local sockets than message queues. Remove character drvier 'factory' it is not necessary.
fs/userfs: Minor reparitioning; volume private info does not need to be held on the OS client side.
libc/userfs: Add some of the server side logic.
fs/userfs: Add some UserFS initialization logic.
fs/userfs: Add frame work for the UserFS proxy. Remove all references to a block driver. There is no block dricer... what was I thinking?
fs/userfs: Add some initialization of the character driver, 'factory' device.
fs/userfs: Rename from fusefs to userfs to that we don't stomp on someone else's cool name.
Add a header file describing the fusefs interface.
This happened after adding these three new procfs entries:
fs/block
fs/mount
fs/usage
Of course, there is no directory fs in this case, only three files that have fs/ in their relative pathnames. The logic was detecting that fs was the name of the enty to report, but it was then declaring that fs was a file (because fs/block is of type file).
This was fixed by adding a check for matching lenghts. i.e., if strlen(fs) != strlen(fs/block), then report fs as a directory instead of a file.
fs/mount: Implements procfs /proc/fs/blocks and /proc/fs/usage files, replacing the NSH df command.
fs/mount: Implements procfs /proc/fs/mount file, replacing the NSH mount command when there are not arguments.
fs/: Move prototype of foreach_mountpoint out of include/nuttx/fs/fs.h to fs/mount/mount.h. Add framework for the mount procfs (initial commit is just a close of the net/route table procfs.
Change all calls to mq_send() and mq_timedsend() in the OS to calls to nxmq_send() and nxmq_timedsend(), making appropriate changes for differences in return values.
sched/mqueue: Add internal function nxmq_send() and nxmq_timedsend() that are equivalent to mq_send() and mq_timedsend() except that they do not create cancellation points and do to not modify the errno variable.
Replace all calls to sigqueue() in the OS proper with calls to nxsig_queue() to avoid accessing the errno variable.
sched/signal: Add nxsig_queue() which is functionally equivalent to sigqueue() except that it does not modify the errno variable.
This is analogous to similar renaming that was done previously for semaphores.
Squashed commit of the following:
sched/signal: Fix a few compile warnings introduced by naming changes.
sched/signal: Rename all private, internal signl functions to use the nxsig_ prefix.
sched/signal: Rename sig_removependingsignal, sig_unmaskpendingsignal, and sig_mqnotempty to nxsig_remove_pendingsignal, nxsig_unmask_pendingsignal, and nxsig_mqnotempty to make it clear that these are OS internal interfaces.
sched/signal: Rename sig_findaction and sig_lowest to nxsig_find_action and nxsig_lowest to make it clear that these are OS internal interfaces.
sched/signal: Rename sig_allocatepingsigaction and sig_deliver to nxsig_alloc_pendingsigaction and nxsig_deliver to make it clear that these are OS internal interfaces.
sched/signal: Rename sig_cleanup, sig_release, sig_releasependingaction, and sig_releasependingsignal to nxsig_cleanup, nxsig_release, nxsig_release_pendingaction, and nxsig_release_pendingsignal to make it clear that these are OS internal interfaces.
sched/signal: Rename sig_tcbdispatch and sig_dispatch to nxsig_tcbdispatch and nxsig_dispatch to make it clear that these are OS internal interfaces.
sched/signal: Rename sig_releaseaction and sig_pendingset to nxsig_release_action and nxsig_pendingset to make it clear that these are OS internal interfaces.
sched/signal: Rename sig_initialize and sig_allocateactionblock to nxsig_initialize and nxsig_alloc_actionblock to make it clear that these are OS internal interfaces.
This commit backs out most of commit b4747286b1. That change was added because sem_wait() would sometimes cause cancellation points inappropriated. But with these recent changes, nxsem_wait() is used instead and it is not a cancellation point.
In the OS, all calls to sem_wait() changed to nxsem_wait(). nxsem_wait() does not return errors via errno so each place where nxsem_wait() is now called must not examine the errno variable.
In all OS functions (not libraries), change sem_wait() to nxsem_wait(). This will prevent the OS from creating bogus cancellation points and from modifying the per-task errno variable.
sched/semaphore: Add the function nxsem_wait(). This is a new internal OS interface. It is functionally equivalent to sem_wait() except that (1) it is not a cancellation point, and (2) it does not set the per-thread errno value on return.
sched/semaphore: Add nxsem_post() which is identical to sem_post() except that it never modifies the errno variable. Changed all references to sem_post in the OS to nxsem_post().
sched/semaphore: Add nxsem_destroy() which is identical to sem_destroy() except that it never modifies the errno variable. Changed all references to sem_destroy() in the OS to nxsem_destroy().
libc/semaphore and sched/semaphore: Add nxsem_getprotocol() and nxsem_setprotocola which are identical to sem_getprotocol() and set_setprotocol() except that they never modifies the errno variable. Changed all references to sem_setprotocol in the OS to nxsem_setprotocol(). sem_getprotocol() was not used in the OS
libc/semaphore: Add nxsem_getvalue() which is identical to sem_getvalue() except that it never modifies the errno variable. Changed all references to sem_getvalue in the OS to nxsem_getvalue().
sched/semaphore: Rename all internal private functions from sem_xyz to nxsem_xyz. The sem_ prefix is (will be) reserved only for the application semaphore interfaces.
libc/semaphore: Add nxsem_init() which is identical to sem_init() except that it never modifies the errno variable. Changed all references to sem_init in the OS to nxsem_init().
sched/semaphore: Rename sem_tickwait() to nxsem_tickwait() so that it is clear this is an internal OS function.
sched/semaphoate: Rename sem_reset() to nxsem_reset() so that it is clear this is an internal OS function.
