Commit Graph

70 Commits

Author SHA1 Message Date
Norman Feske
eba9c15746 Follow practices suggested by "Effective C++"
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
2018-01-17 12:14:35 +01:00
Sebastian Sumpf
9c852c750a vfs: handle root directory explicitly
This makes '/' and the actual root of VFS distinguishable. A VFS root
may contain one ore more '/' entries for each file system. 'opendir' for
the VFS root opens all file systems via 'open_composite_dir', while
'opendir' for '/' only returns a VFS handle.

Fixes #2569
2017-11-30 11:23:10 +01:00
Emery Hemingway
07b36573ea Restrict VFS Dir_filesystem allocations to 'opendir' only
Allocations made at the client-side of the VFS must be contained within
functions that may return errors indicating resource exhaustion.

Fix #2569
2017-11-30 11:23:02 +01:00
Emery Hemingway
a0c0f3d7c9 Print support for VFS errors
Ref #2569
2017-11-30 11:23:02 +01:00
Josef Söntgen
e1ada57bfa vfs: use unsigned 64bit for media size ioctl
Fixes #2523.
2017-10-05 17:40:02 +02:00
Christian Prochaska
b0935ef9b2 VFS: nonblocking interface
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
2017-08-28 16:49:38 +02:00
Emery Hemingway
1eb37fbe22 VFS: move 'sync' from 'File_system' to 'Directory_service'
The the parent 'Directory_service' interface is reachable from
'Vfs_handle', whereas the 'File_system' interface is not.

Fix #2437
Ref #2422
2017-06-12 14:32:07 +02:00
Norman Feske
29b8d609c9 Adjust file headers to refer to the AGPLv3 2017-02-28 12:59:29 +01:00
Josef Söntgen
69c48a3626 os: refactor Global_file_system_factory
The global file system factory is now created explicitly and the
global singleton accessor function was removed.

Fixes #2281.
2017-02-28 12:59:23 +01:00
Christian Helmuth
61b6dccf13 Queued read/write/read_ready in VFS and servers 2017-02-23 15:03:28 +01:00
Sebastian Sumpf
aa602032dd vfs: dynamic configuration support 2017-02-23 14:54:48 +01:00
Christian Helmuth
f9389109bf Support select in libc VFS plugin by read_ready() 2017-02-07 11:12:29 +01:00
Christian Helmuth
c0d61858c3 Support for suspendable read in VFS and libC
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().
2017-02-07 11:12:27 +01:00
Emery Hemingway
bae4ce5360 lib/vfs: deduplicate symlink and single_file
Issue #1891
2016-11-08 15:26:31 +01:00
Emery Hemingway
ddf3716cff vfs: pass Env and allocator when creating file-systems
Fix #1891
2016-11-08 15:26:31 +01:00
Emery Hemingway
beebd394fc lib/vfs: seperate implemention and API headers
Issue #1891
2016-11-08 15:26:30 +01:00
Norman Feske
17c79a9e23 base: avoid use of deprecated base/printf.h
Besides adapting the components to the use of base/log.h, the patch
cleans up a few base headers, i.e., it removes unused includes from
root/component.h, specifically base/heap.h and
ram_session/ram_session.h. Hence, components that relied on the implicit
inclusion of those headers have to manually include those headers now.

While adjusting the log messages, I repeatedly stumbled over the problem
that printing char * arguments is ambiguous. It is unclear whether to
print the argument as pointer or null-terminated string. To overcome
this problem, the patch introduces a new type 'Cstring' that allows the
caller to express that the argument should be handled as null-terminated
string. As a nice side effect, with this type in place, the optional len
argument of the 'String' class could be removed. Instead of supplying a
pair of (char const *, size_t), the constructor accepts a 'Cstring'.
This, in turn, clears the way let the 'String' constructor use the new
output mechanism to assemble a string from multiple arguments (and
thereby getting rid of snprintf within Genode in the near future).

To enforce the explicit resolution of the char * ambiguity, the 'char *'
overload of the 'print' function is marked as deleted.

Issue #1987
2016-08-29 17:27:10 +02:00
Christian Helmuth
d8c34237bf vfs: default constructor for Dirent and Stat
Fixes #1743
2016-06-28 11:09:27 +02:00
Emery Hemingway
0a01edded2 Path::strip_last_element removes path delimiter
Remove the trailing slash of a path where the path is not "/".
New Path::append_element convenience function.

Fixes #1744
2016-06-28 11:09:27 +02:00
Norman Feske
807be83b1b Remove inconsistent use of 'is_' prefix
Fixes #1963
2016-05-23 15:52:39 +02:00
Josef Söntgen
59aec6114b vfs_block: remove diagnostic warnings
These warnings are triggered by requests either using byte offsets or
reading a number of bytes that is not a multiple of the block size as
well as by components using the plugin with a different block size than
the backend block session provides.

Fixes #1964.
2016-05-23 15:52:38 +02:00
Christian Helmuth
b38c5006d8 vfs: support UNLINK_ERR_NO_ENTRY in TAR file system
We report UNLINK_ERR_NO_PERM only for files in TAR archive, otherwise
UNLINK_ERR_NO_ENTRY is returned. This permits the arbitrary layering of
file systems with support for proper ENOENT reporting, for example,
when using 'rm -f non_existent_file' that aborts if EPERM is wrongly
reported.
2016-05-09 13:10:53 +02:00
Emery Hemingway
549f77eafe Catch exceptions when creating VFS
Catch exceptions at File_system_factory::create.
Print error message in Dir_file_system.

Fixes #1786
2016-05-09 13:10:51 +02:00
Emery Hemingway
ccd50cc9f5 Vfs::Dir_file_system: adjust rename error priority
CROSS_FS error must not propagate before NO_PERM.
New order is OK, NO_PERM, CROSS_FS, NO_ENTRY.

Fixes #1900
2016-04-25 11:02:02 +02:00
Christian Helmuth
579f4d4991 vfs: count of written bytes in Fs_file_system 2016-04-25 10:48:01 +02:00
Emery Hemingway
1d301e9c14 lib/vfs: consistent device and inode enumeration
Issue #1751
2016-04-25 10:47:54 +02:00
Emery Hemingway
b8e52189d5 lib/vfs: new permissions errors
New errors STAT_ERR_NO_PERM, DIRENT_ERR_NO_PERM, and READLINK_NO_PERM to
distinguish lookup errors from permissions or other errors.

Issue #1751
2016-04-25 10:47:54 +02:00
Emery Hemingway
14ca140135 lib/vfs: fix disappearing <dir><dir/></dir>
Issue #1751
2016-04-25 10:47:53 +02:00
Emery Hemingway
cb952d2087 obscure File_system::Out_of_node_handles exception
Replace the Out_of_node_handles exception with Out_of_metadata.
Clients need to know when the server is out of internal resources,
but not why.

Cleanup and sort the errors at file_system_session.h.
Remove 'Size_limit_reached exception' from File_system, which was
internal to ram_fs.

Issue #1751
Fixes #1909
2016-04-25 10:47:52 +02:00
Emery Hemingway
58632ab8b5 lib/vfs: improve memory safety at ram file system
Reference count files to prevent dangling handles.
Catch out-of-memory conditions and throw NO_SPACE.

Issue #1751
2016-04-11 12:56:54 +02:00
Emery Hemingway
82a7799638 lib/vfs: pass handle allocator to open(...)
Opening a VFS handle previously involved allocating from the global heap
at each VFS file system. By amending open with an allocator argument,
dynamic allocation can be partitioned.

A new close method is used to deallocate open handles.

Issue #1751
Issue #1891
2016-04-11 12:56:54 +02:00
Christian Prochaska
146c694513 Reduce the maximum LOG session string length
The maximum possible string length is defined by the platform with the
lowest maximum IPC payload size (currently OKL4).

Fixes #1919
2016-04-11 11:51:43 +02:00
Emery Hemingway
23c1d4c66d libc, vfs: rename improvements
Perform POSIX rename checks at the libc VFS plugin.
Clarify rename at VFS fs, ram, single, and tar file systems.

Issue #1900
Fixes #1782
2016-03-07 12:40:04 +01:00
Norman Feske
fc6c2537ee vfs: add Rom_file_system::dataspace
By providing this function, we can start a mounted ROM module as program
under Noux.
2016-01-26 16:20:37 +01:00
Emery Hemingway
56c637c1f6 VFS tar: always set dirent type
Assume tar nodes with missing records are directories.

Fixes #1843
2016-01-08 14:37:58 +01:00
Emery Hemingway
ee25dcbae3 VFS: check path on the symlink node readlink
Fixes #1790
2015-11-29 18:17:05 +01:00
Emery Hemingway
1d92631ef0 VFS, File_system: Not_empty
Unlink returns an error for non-empty directories when the backend does
not support recursive unlinking.

Fixes #1750
2015-11-29 18:17:05 +01:00
Emery Hemingway
6cb0f3bb71 VFS ram: remove quota
Fixes #1780
2015-11-29 18:17:05 +01:00
Alexander Boettcher
3789a75ed6 base: support ascii_to for uint64_t
Issue #1764
2015-11-18 12:22:07 +01:00
Sebastian Sumpf
06fe755f8c noux: Enable setting of file handle flags
Fixes #1765
2015-11-18 12:22:04 +01:00
Emery Hemingway
8ed6364388 refactor Vfs::Ram_file_system
Issue #1648
2015-11-04 14:09:24 +01:00
Emery Hemingway
cdb44850d3 Strip slashes from Path in Vfs::Fs_file_system
strip_last_element at Path removes everything after the trailing slash,
which causes lookup failures at the VFS server when opening directories.

Issue #1648
2015-11-04 14:09:24 +01:00
Emery Hemingway
1c6164a0c5 File_system session: broaden error handling
Throw Invalid_name, No_space, and Out_of_node_handles where appropriate.

Catch the new range of errors thrown by at the VFS.
Catch Out_of_node_handles at the VFS, but print a message and re-throw.

Issue #1648
2015-11-04 14:09:24 +01:00
Emery Hemingway
1d4bd10701 fix handle leak in Vfs::Fs_file_system
Issue #1648
2015-11-04 14:09:23 +01:00
Emery Hemingway
48fd034cfe New session arguments at File_system connection
Session root and writeablity may be specified at the session
convenience constructor.

Issue #1648
2015-11-04 14:09:23 +01:00
Emery Hemingway
2da239d0c8 void sync(char const *path)
Sync now takes a path argument at VFS and File system interfaces.

Issue #1648
2015-11-04 14:09:23 +01:00
Emery Hemingway
1779a0511b vfs: add new error codes
The codes are OPEN_ERR_NAME_TOO_LONG, OPEN_ERR_NO_SPACE, and
FTRUNCATE_ERR_NO_SPACE.

Issue #1693
2015-10-06 12:18:51 +02:00
Christian Helmuth
24b1f269be Remove Packet_ref from File_system::Packet_descriptor
The intention of Packet_ref was to allow clients to place opaque
references into the packet descriptor itself, which could be observed on
packet completion. Currently no component in our sources uses this
feature and beyond that it is questionable if it should be used at all:
If the server tampers with the ref the client may easily be confused
into observing an incorrect or invalid context. It seems better to
remove the opaque context from the descriptor and leave the actual
implementation to the client and its needs.
2015-09-30 12:20:37 +02:00
Emery Hemingway
7ce19216f4 VFS: symlink file system
add symlinks to a VFS tree with <symlink name="..." target="..."/>

Issue #1648
Fixes #1653
2015-09-30 12:20:36 +02:00
Emery Hemingway
4a5b7be4e7 TAR VFS: dereference hard links when opening files
Fixes #1636
Issue #1653
2015-09-30 12:20:35 +02:00