The 'file_size' type denotes the size of files on disk in bytes. On
32-bit architectures it is larger than the size_t, which refers to
in-memory object sizes.
Whereas the use of 'file_size' is appropriate for ftruncate and seek, it
is not a suitable type for the parameters of read/write operations
because those operations refer to in-memory buffers.
This patch replaces the use of 'file_size' by size_t. However, since it
affects all sites where the read/write interface is uses, it takes the
opportunity to replace the C-style (pointer, size) arguments by
'Byte_range_ptr' and 'Const_byte_range_ptr'.
Issue #4706
This commit supplements the various I/O signal handlers of the VFS
plugins with calls of the new 'Vfs::Env::User::wakeup_vfs_user'
interface, which will subsequently replace the old 'Io_progress_handler'
(issue #4697).
Issue #4706
By adding a 'write_ready' interface following the lines of the existing
'read_ready', VFS plugins become able to propagate the (de-)saturation
of I/O buffers to the VFS user. This information is important when using
a non-blocking file descriptor for writing into a TCP socket. Once the
application observes EAGAIN, it expects a subsequent 'select' call to
return as soon as new I/O buffer space becomes available.
Before this patch, the select call would always return under this
condition, causing an unnecessarily busy write loop.
Issue #4697
Clang likes to complain when lambdas capture parameters without
actually using them. This patch fixes a couple of such problems in VFS
related os module code.
Issue #4421
An invalid ROM dataspace can occur, for example, when requesting a ROM
from the report_rom service before the first report was posted. Such a
<rom> node can still be useful if it's dynamic. E.g., it can be watched.
Hence, the corner case of an invalid ROM dataspace should be gracefully
handled instead of causing an abort.
Issue #3606
This patch extends the 'File_system::Status',
'File_system::Directory_entry', and the related 'Vfs' types with
the following additional information:
- Distinction between continuous and transactional files (Node_type)
(issue #3507)
- Readable, writeable, and executable attributes (Node_rwx),
replacing the former 'mode' bits
(issue #3030)
The types 'Node_rwx', 'Node_type' are defined twice,
once for the VFS (vfs/types.h) and once for the 'File_system'
session (file_system_session/file_system_session.h).
Similarly, there is a direct correspondance between
'Vfs::Directory_service::Dirent' and 'File_system::Directory_entry'.
This duplication of types follows the existing pattern of keeping the
VFS and file-system session independent from each other.
When mounting a ROM module with binary="no", the
vfs will detect the 0-termination to calculate the
file size instead of using the dataspace size.
Fixes#2903
The 'stat' method is called for all paths, not just the specific file
system node of the ROM module. The ROM update is needed only in the
latter case.
Otherwise, when always updating the ROM on stat, stat calls on the VFS
become very expensive in the presence of a mounted ROM module if the ROM
is obtained from fs_rom (which re-watches the file and all its
individual path elements whenever the 'update' RPC function is called).
Reduce the size and forward compatibility of VFS file-system
constructors by passing an object holding accessors for 'Genode::Env',
'Genode::Allocator', response handlers, and the root file-system.
Fix#2742
This patch enables the use of the VFS from VFS plugins by passing a
reference of the root directory to the constructors of file-system
instances. Since it changes the signature of 'Vfs::Dir_file_system',
any code that uses the VFS directly requires an adaptation.
Fixes#2701
Catch out of RAM and capability exceptions and return error values.
Abort opening a composite directory at Dir_file_system where an
opendir call on any child file-system returns an OUT_OF_RAM or
OUT_OF_CAPS error.
Ref #2642
The patch adjust the code of the base, base-<kernel>, and os repository.
To adapt existing components to fix violations of the best practices
suggested by "Effective C++" as reported by the -Weffc++ compiler
argument. The changes follow the patterns outlined below:
* A class with virtual functions can no longer publicly inherit base
classed without a vtable. The inherited object may either be moved
to a member variable, or inherited privately. The latter would be
used for classes that inherit 'List::Element' or 'Avl_node'. In order
to enable the 'List' and 'Avl_tree' to access the meta data, the
'List' must become a friend.
* Instead of adding a virtual destructor to abstract base classes,
we inherit the new 'Interface' class, which contains a virtual
destructor. This way, single-line abstract base classes can stay
as compact as they are now. The 'Interface' utility resides in
base/include/util/interface.h.
* With the new warnings enabled, all member variables must be explicitly
initialized. Basic types may be initialized with '='. All other types
are initialized with braces '{ ... }' or as class initializers. If
basic types and non-basic types appear in a row, it is nice to only
use the brace syntax (also for basic types) and align the braces.
* If a class contains pointers as members, it must now also provide a
copy constructor and assignment operator. In the most cases, one
would make them private, effectively disallowing the objects to be
copied. Unfortunately, this warning cannot be fixed be inheriting
our existing 'Noncopyable' class (the compiler fails to detect that
the inheriting class cannot be copied and still gives the error).
For now, we have to manually add declarations for both the copy
constructor and assignment operator as private class members. Those
declarations should be prepended with a comment like this:
/*
* Noncopyable
*/
Thread(Thread const &);
Thread &operator = (Thread const &);
In the future, we should revisit these places and try to replace
the pointers with references. In the presence of at least one
reference member, the compiler would no longer implicitly generate
a copy constructor. So we could remove the manual declaration.
Issue #465
The VFS library can be used in single-threaded or multi-threaded
environments and depending on that, signals are handled by the same thread
which uses the VFS library or possibly by a different thread. If a VFS
plugin needs to block to wait for a signal, there is currently no way
which works reliably in both environments.
For this reason, this commit makes the interface of the VFS library
nonblocking, similar to the File_system session interface.
The most important changes are:
- Directories are created and opened with the 'opendir()' function and the
directory entries are read with the recently introduced 'queue_read()'
and 'complete_read()' functions.
- Symbolic links are created and opened with the 'openlink()' function and
the link target is read with the 'queue_read()' and 'complete_read()'
functions and written with the 'write()' function.
- The 'write()' function does not wait for signals anymore. This can have
the effect that data written by a VFS library user has not been
processed by a file system server yet when the library user asks for the
size of the file or closes it (both done with RPC functions at the file
system server). For this reason, a user of the VFS library should
request synchronization before calling 'stat()' or 'close()'. To make
sure that a file system server has processed all write request packets
which a client submitted before the synchronization request,
synchronization is now requested at the file system server with a
synchronization packet instead of an RPC function. Because of this
change, the synchronization interface of the VFS library is now split
into 'queue_sync()' and 'complete_sync()' functions.
Fixes#2399
The support has two parts. First, a VFS plugin now gets passed an
I/O-response handler callback on construction, which informs users of the
VFS that an I/O event occurred. This enables, for example, the libC to
check if blocking read can be completed. Further, the VFS file I/O
interface provides now functions for suspendable reads, i.e.,
queue_read() and complete_read().
