mirror of
https://github.com/genodelabs/genode.git
synced 2024-12-27 09:12:32 +00:00
9dd04ad268
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
1032 lines
26 KiB
C++
1032 lines
26 KiB
C++
/*
|
|
* \brief Directory file system
|
|
* \author Norman Feske
|
|
* \author Emery Hemingway
|
|
* \author Christian Helmuth
|
|
* \date 2012-04-23
|
|
*/
|
|
|
|
/*
|
|
* Copyright (C) 2011-2019 Genode Labs GmbH
|
|
*
|
|
* This file is part of the Genode OS framework, which is distributed
|
|
* under the terms of the GNU Affero General Public License version 3.
|
|
*/
|
|
|
|
#ifndef _INCLUDE__VFS__DIR_FILE_SYSTEM_H_
|
|
#define _INCLUDE__VFS__DIR_FILE_SYSTEM_H_
|
|
|
|
#include <base/registry.h>
|
|
#include <vfs/file_system_factory.h>
|
|
#include <vfs/vfs_handle.h>
|
|
|
|
|
|
namespace Vfs { class Dir_file_system; }
|
|
|
|
|
|
class Vfs::Dir_file_system : public File_system
|
|
{
|
|
public:
|
|
|
|
enum { MAX_NAME_LEN = 128 };
|
|
|
|
private:
|
|
|
|
/*
|
|
* Noncopyable
|
|
*/
|
|
Dir_file_system(Dir_file_system const &);
|
|
Dir_file_system &operator = (Dir_file_system const &);
|
|
|
|
Vfs::Env &_env;
|
|
|
|
/**
|
|
* This instance is the root of VFS
|
|
*
|
|
* Additionally, the root has an empty _name.
|
|
*/
|
|
bool const _vfs_root;
|
|
|
|
struct Dir_vfs_handle : Vfs_handle
|
|
{
|
|
struct Subdir_handle_element;
|
|
|
|
typedef Genode::Registry<Subdir_handle_element> Subdir_handle_registry;
|
|
|
|
struct Subdir_handle_element : Subdir_handle_registry::Element
|
|
{
|
|
bool synced { false };
|
|
|
|
Vfs_handle &vfs_handle;
|
|
Subdir_handle_element(Subdir_handle_registry ®istry,
|
|
Vfs_handle &vfs_handle)
|
|
: Subdir_handle_registry::Element(registry, *this),
|
|
vfs_handle(vfs_handle) { }
|
|
};
|
|
|
|
Absolute_path path;
|
|
Vfs_handle *queued_read_handle { nullptr };
|
|
Subdir_handle_registry subdir_handle_registry { };
|
|
|
|
Dir_vfs_handle(Directory_service &ds,
|
|
File_io_service &fs,
|
|
Genode::Allocator &alloc,
|
|
char const *path)
|
|
: Vfs_handle(ds, fs, alloc, 0),
|
|
path(path) { }
|
|
|
|
~Dir_vfs_handle()
|
|
{
|
|
/* close all sub-handles */
|
|
auto f = [&] (Subdir_handle_element &e) {
|
|
e.vfs_handle.close();
|
|
destroy(alloc(), &e);
|
|
};
|
|
subdir_handle_registry.for_each(f);
|
|
}
|
|
|
|
private:
|
|
|
|
/*
|
|
* Noncopyable
|
|
*/
|
|
Dir_vfs_handle(Dir_vfs_handle const &);
|
|
Dir_vfs_handle &operator = (Dir_vfs_handle const &);
|
|
};
|
|
|
|
struct Dir_watch_handle : Vfs_watch_handle
|
|
{
|
|
struct Watch_handle_element;
|
|
|
|
typedef Genode::Registry<Watch_handle_element> Watch_handle_registry;
|
|
|
|
struct Watch_handle_element : Watch_handle_registry::Element
|
|
{
|
|
Vfs_watch_handle &watch_handle;
|
|
Watch_handle_element(Watch_handle_registry ®istry,
|
|
Vfs_watch_handle &handle)
|
|
: Watch_handle_registry::Element(registry, *this),
|
|
watch_handle(handle) { }
|
|
};
|
|
|
|
Watch_handle_registry handle_registry { };
|
|
|
|
Dir_watch_handle(File_system &fs, Genode::Allocator &alloc)
|
|
: Vfs_watch_handle(fs, alloc) { }
|
|
|
|
~Dir_watch_handle()
|
|
{
|
|
/* close all sub-handles */
|
|
auto f = [&] (Watch_handle_element &e) {
|
|
e.watch_handle.close();
|
|
destroy(alloc(), &e);
|
|
};
|
|
handle_registry.for_each(f);
|
|
}
|
|
|
|
/**
|
|
* Propagate the response handler to each sub-handle
|
|
*/
|
|
void handler(Watch_response_handler *h) override
|
|
{
|
|
handle_registry.for_each( [&] (Watch_handle_element &elem) {
|
|
elem.watch_handle.handler(h); } );
|
|
}
|
|
};
|
|
|
|
|
|
/* pointer to first child file system */
|
|
File_system *_first_file_system = nullptr;
|
|
|
|
/* add new file system to the list of children */
|
|
void _append_file_system(File_system *fs)
|
|
{
|
|
if (!_first_file_system) {
|
|
_first_file_system = fs;
|
|
return;
|
|
}
|
|
|
|
File_system *curr = _first_file_system;
|
|
while (curr->next)
|
|
curr = curr->next;
|
|
|
|
curr->next = fs;
|
|
}
|
|
|
|
/**
|
|
* Directory name
|
|
*/
|
|
typedef String<MAX_NAME_LEN> Name;
|
|
Name const _name;
|
|
|
|
/**
|
|
* Returns if path corresponds to top directory of file system
|
|
*/
|
|
bool _top_dir(char const *path) const { return strcmp(path, "/") == 0; }
|
|
|
|
/**
|
|
* Perform operation on a file system
|
|
*
|
|
* \param fn functor that takes a file-system reference and
|
|
* the path as arguments
|
|
*/
|
|
template <typename RES, typename FN>
|
|
RES _dir_op(RES const no_entry, RES const no_perm, RES const ok,
|
|
char const *path, FN const &fn)
|
|
{
|
|
path = _sub_path(path);
|
|
|
|
/* path does not match directory name */
|
|
if (!path)
|
|
return no_entry;
|
|
|
|
/*
|
|
* Prevent operation if path equals directory name defined
|
|
* via the static VFS configuration.
|
|
*/
|
|
if (strlen(path) == 0)
|
|
return no_perm;
|
|
|
|
/*
|
|
* If any of the sub file systems returns a permission error and
|
|
* there exists no sub file system that takes the request, we
|
|
* return the permission error.
|
|
*/
|
|
bool permission_denied = false;
|
|
|
|
/*
|
|
* Keep the most meaningful error code. When using stacked file
|
|
* systems, most child file systems will eventually return no
|
|
* entry (or leave the error code unchanged). If any of those
|
|
* file systems has anything more interesting to tell, return
|
|
* this information after all file systems have been tried and
|
|
* none could handle the request.
|
|
*/
|
|
RES error = ok;
|
|
|
|
/*
|
|
* The given path refers to at least one of our sub directories.
|
|
* Propagate the request into all of our file systems. If at least
|
|
* one operation succeeds, we return success.
|
|
*/
|
|
for (File_system *fs = _first_file_system; fs; fs = fs->next) {
|
|
|
|
RES const err = fn(*fs, path);
|
|
|
|
if (err == ok)
|
|
return err;
|
|
|
|
if (err != no_entry && err != no_perm) {
|
|
error = err;
|
|
}
|
|
|
|
if (err == no_perm)
|
|
permission_denied = true;
|
|
}
|
|
|
|
/* none of our file systems could successfully operate on the path */
|
|
return error != ok ? error : permission_denied ? no_perm : no_entry;
|
|
}
|
|
|
|
/**
|
|
* Return portion of the path after the element corresponding to
|
|
* the current directory.
|
|
*/
|
|
char const *_sub_path(char const *path) const
|
|
{
|
|
/* do not strip anything from the path when we are root */
|
|
if (_vfs_root)
|
|
return path;
|
|
|
|
if (_top_dir(path))
|
|
return path;
|
|
|
|
/* skip heading slash in path if present */
|
|
if (path[0] == '/')
|
|
path++;
|
|
|
|
Genode::size_t const name_len = strlen(_name.string());
|
|
if (strcmp(path, _name.string(), name_len) != 0)
|
|
return 0;
|
|
path += name_len;
|
|
|
|
/*
|
|
* The first characters of the first path element are equal to
|
|
* the current directory name. Let's check if the length of the
|
|
* first path element matches the name length.
|
|
*/
|
|
if (*path != 0 && *path != '/')
|
|
return 0;
|
|
|
|
return path;
|
|
}
|
|
|
|
/*
|
|
* Accumulate number of directory entries that match in any of
|
|
* our sub file systems.
|
|
*/
|
|
file_size _sum_dirents_of_file_systems(char const *path)
|
|
{
|
|
file_size cnt = 0;
|
|
for (File_system *fs = _first_file_system; fs; fs = fs->next) {
|
|
cnt += fs->num_dirent(path);
|
|
}
|
|
return cnt;
|
|
}
|
|
|
|
bool _queue_read_of_file_systems(Dir_vfs_handle *dir_vfs_handle)
|
|
{
|
|
bool result = true;
|
|
|
|
dir_vfs_handle->queued_read_handle = nullptr;
|
|
|
|
file_offset index = dir_vfs_handle->seek() / sizeof(Dirent);
|
|
|
|
char const *sub_path = _sub_path(dir_vfs_handle->path.base());
|
|
|
|
if (strlen(sub_path) == 0)
|
|
sub_path = "/";
|
|
|
|
/* base of composite directory index */
|
|
int base = 0;
|
|
|
|
auto f = [&] (Dir_vfs_handle::Subdir_handle_element &handle_element) {
|
|
if (dir_vfs_handle->queued_read_handle) return; /* skip through */
|
|
|
|
Vfs_handle &vfs_handle = handle_element.vfs_handle;
|
|
|
|
/*
|
|
* Determine number of matching directory entries within
|
|
* the current file system.
|
|
*/
|
|
int const fs_num_dirent = (int)vfs_handle.ds().num_dirent(sub_path);
|
|
|
|
/*
|
|
* Query directory entry if index lies with the file
|
|
* system.
|
|
*/
|
|
if (index - base < fs_num_dirent) {
|
|
/* set this handle to be used for read completion */
|
|
dir_vfs_handle->queued_read_handle = &vfs_handle;
|
|
|
|
/* seek to file-system local index */
|
|
index = index - base;
|
|
vfs_handle.seek(index * sizeof(Dirent));
|
|
|
|
/* forward the response handler */
|
|
dir_vfs_handle->apply_handler([&] (Vfs::Io_response_handler &h) {
|
|
vfs_handle.handler(&h); });
|
|
|
|
result = vfs_handle.fs().queue_read(&vfs_handle, sizeof(Dirent));
|
|
}
|
|
|
|
/* adjust base index for next file system */
|
|
base += fs_num_dirent;
|
|
};
|
|
|
|
dir_vfs_handle->subdir_handle_registry.for_each(f);
|
|
|
|
return result;
|
|
}
|
|
|
|
Read_result _complete_read_of_file_systems(Dir_vfs_handle *dir_vfs_handle,
|
|
char *dst, file_size count,
|
|
file_size &out_count)
|
|
{
|
|
if (!dir_vfs_handle->queued_read_handle) {
|
|
|
|
/*
|
|
* no fs was found for the given index or
|
|
* fs->opendir() failed
|
|
*/
|
|
|
|
if (count < sizeof(Dirent))
|
|
return READ_ERR_INVALID;
|
|
|
|
Dirent &dirent = *(Dirent*)dst;
|
|
dirent = Dirent { };
|
|
|
|
out_count = sizeof(Dirent);
|
|
|
|
return READ_OK;
|
|
}
|
|
|
|
Read_result result = dir_vfs_handle->queued_read_handle->fs().
|
|
complete_read(dir_vfs_handle->queued_read_handle,
|
|
dst, count, out_count);
|
|
|
|
if (result == READ_QUEUED)
|
|
return result;
|
|
|
|
dir_vfs_handle->queued_read_handle = nullptr;
|
|
|
|
return result;
|
|
}
|
|
|
|
public:
|
|
|
|
Dir_file_system(Vfs::Env &env,
|
|
Genode::Xml_node node,
|
|
File_system_factory &fs_factory)
|
|
:
|
|
_env(env),
|
|
_vfs_root(!node.has_type("dir")),
|
|
_name(_vfs_root ? Name() : node.attribute_value("name", Name()))
|
|
{
|
|
using namespace Genode;
|
|
|
|
for (unsigned i = 0; i < node.num_sub_nodes(); i++) {
|
|
|
|
Xml_node sub_node = node.sub_node(i);
|
|
|
|
/* traverse into <dir> nodes */
|
|
if (sub_node.has_type("dir")) {
|
|
_append_file_system(new (_env.alloc())
|
|
Dir_file_system(_env, sub_node, fs_factory));
|
|
continue;
|
|
}
|
|
|
|
File_system * const fs =
|
|
fs_factory.create(_env, sub_node);
|
|
|
|
if (fs) {
|
|
_append_file_system(fs);
|
|
continue;
|
|
}
|
|
|
|
Genode::error("failed to create <", sub_node.type(), "> VFS node");
|
|
try {
|
|
for (unsigned i = 0; i < 16; ++i) {
|
|
|
|
Xml_attribute const attr = sub_node.attribute(i);
|
|
|
|
String<64> value { };
|
|
attr.value(value);
|
|
|
|
Genode::error("\t", attr.name(), "=\"", value, "\"");
|
|
}
|
|
} catch (Xml_node::Nonexistent_attribute) { }
|
|
}
|
|
}
|
|
|
|
/*********************************
|
|
** Directory-service interface **
|
|
*********************************/
|
|
|
|
Dataspace_capability dataspace(char const *path) override
|
|
{
|
|
path = _sub_path(path);
|
|
if (!path)
|
|
return Dataspace_capability();
|
|
|
|
/*
|
|
* Query sub file systems for dataspace using the path local to
|
|
* the respective file system
|
|
*/
|
|
File_system *fs = _first_file_system;
|
|
for (; fs; fs = fs->next) {
|
|
Dataspace_capability ds = fs->dataspace(path);
|
|
if (ds.valid())
|
|
return ds;
|
|
}
|
|
|
|
return Dataspace_capability();
|
|
}
|
|
|
|
void release(char const *path, Dataspace_capability ds_cap) override
|
|
{
|
|
path = _sub_path(path);
|
|
if (!path)
|
|
return;
|
|
|
|
for (File_system *fs = _first_file_system; fs; fs = fs->next)
|
|
fs->release(path, ds_cap);
|
|
}
|
|
|
|
Stat_result stat(char const *path, Stat &out) override
|
|
{
|
|
path = _sub_path(path);
|
|
|
|
/* path does not match directory name */
|
|
if (!path)
|
|
return STAT_ERR_NO_ENTRY;
|
|
|
|
/*
|
|
* If path equals directory name, return information about the
|
|
* current directory.
|
|
*/
|
|
if (strlen(path) == 0 || _top_dir(path)) {
|
|
out = {
|
|
.size = 0,
|
|
.type = Node_type::DIRECTORY,
|
|
.rwx = Node_rwx::rwx(),
|
|
.inode = 1,
|
|
.device = (Genode::addr_t)this,
|
|
.modification_time = { Vfs::Timestamp::INVALID },
|
|
};
|
|
return STAT_OK;
|
|
}
|
|
|
|
/*
|
|
* The given path refers to one of our sub directories.
|
|
* Propagate the request into our file systems.
|
|
*/
|
|
for (File_system *fs = _first_file_system; fs; fs = fs->next) {
|
|
|
|
Stat_result const err = fs->stat(path, out);
|
|
|
|
if (err == STAT_OK)
|
|
return err;
|
|
|
|
if (err != STAT_ERR_NO_ENTRY)
|
|
return err;
|
|
}
|
|
|
|
/* none of our file systems felt responsible for the path */
|
|
return STAT_ERR_NO_ENTRY;
|
|
}
|
|
|
|
file_size num_dirent(char const *path) override
|
|
{
|
|
if (_vfs_root) {
|
|
return _sum_dirents_of_file_systems(path);
|
|
|
|
} else {
|
|
|
|
if (_top_dir(path))
|
|
return 1;
|
|
|
|
/*
|
|
* The path contains at least one element. Remove current
|
|
* element from path.
|
|
*/
|
|
path = _sub_path(path);
|
|
|
|
/*
|
|
* If the resulting 'path' is non-null, the path lies
|
|
* within our tree. In this case, determine the sum of
|
|
* matching dirents of all our file systems. Otherwise,
|
|
* the specified path lies outside our directory node.
|
|
*/
|
|
return path ? _sum_dirents_of_file_systems(*path ? path : "/") : 0;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Return true if specified path is a directory
|
|
*/
|
|
bool directory(char const *path) override
|
|
{
|
|
if (_top_dir(path))
|
|
return true;
|
|
|
|
path = _sub_path(path);
|
|
|
|
if (!path)
|
|
return false;
|
|
|
|
if (strlen(path) == 0)
|
|
return true;
|
|
|
|
for (File_system *fs = _first_file_system; fs; fs = fs->next)
|
|
if (fs->directory(path))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
char const *leaf_path(char const *path) override
|
|
{
|
|
path = _sub_path(path);
|
|
if (!path)
|
|
return nullptr;
|
|
|
|
if (strlen(path) == 0)
|
|
return path;
|
|
|
|
for (File_system *fs = _first_file_system; fs; fs = fs->next) {
|
|
char const *leaf_path = fs->leaf_path(path);
|
|
if (leaf_path)
|
|
return leaf_path;
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Open_result open(char const *path,
|
|
unsigned mode,
|
|
Vfs_handle **out_handle,
|
|
Allocator &alloc) override
|
|
{
|
|
/*
|
|
* If 'path' is a directory, we create a 'Vfs_handle'
|
|
* for the root directory so that subsequent 'dirent' calls
|
|
* are subjected to the stacked file-system layout.
|
|
*/
|
|
if (directory(path)) {
|
|
try {
|
|
*out_handle = new (alloc) Dir_vfs_handle(*this, *this, alloc, path);
|
|
return OPEN_OK;
|
|
}
|
|
catch (Genode::Out_of_ram) { return OPEN_ERR_OUT_OF_RAM; }
|
|
catch (Genode::Out_of_caps) { return OPEN_ERR_OUT_OF_CAPS; }
|
|
}
|
|
|
|
/*
|
|
* If 'path' refers to a non-directory node, create a
|
|
* 'Vfs_handle' local to the file system that provides the
|
|
* file.
|
|
*/
|
|
|
|
path = _sub_path(path);
|
|
|
|
/* check if path does not match directory name */
|
|
if (!path)
|
|
return OPEN_ERR_UNACCESSIBLE;
|
|
|
|
/* path equals directory name */
|
|
if (strlen(path) == 0) {
|
|
try {
|
|
*out_handle = new (alloc) Vfs_handle(*this, *this, alloc, 0);
|
|
return OPEN_OK;
|
|
}
|
|
catch (Genode::Out_of_ram) { return OPEN_ERR_OUT_OF_RAM; }
|
|
catch (Genode::Out_of_caps) { return OPEN_ERR_OUT_OF_CAPS; }
|
|
}
|
|
|
|
/* path refers to any of our sub file systems */
|
|
for (File_system *fs = _first_file_system; fs; fs = fs->next) {
|
|
|
|
Open_result const err = fs->open(path, mode, out_handle, alloc);
|
|
switch (err) {
|
|
case OPEN_ERR_UNACCESSIBLE:
|
|
continue;
|
|
default:
|
|
return err;
|
|
}
|
|
}
|
|
|
|
/* path does not match any existing file or directory */
|
|
return OPEN_ERR_UNACCESSIBLE;
|
|
}
|
|
|
|
/**
|
|
* Call 'opendir()' on each file system and store handles in
|
|
* a registry.
|
|
*/
|
|
Opendir_result open_composite_dirs(char const *sub_path,
|
|
Dir_vfs_handle &dir_vfs_handle)
|
|
{
|
|
Opendir_result res;
|
|
if (strcmp(sub_path, "/")) {
|
|
|
|
/*
|
|
* If there are still directory names in the sub-path, we have
|
|
* not reached the leaf node of the original path so far.
|
|
* Therefore, if the current directory is empty, this means
|
|
* that the original path refers to a directory that doesn't
|
|
* exist. Consequently, the result defaults to a
|
|
* "lookup failed" error.
|
|
*/
|
|
res = OPENDIR_ERR_LOOKUP_FAILED;
|
|
|
|
} else {
|
|
|
|
/*
|
|
* We have reached the leaf node of the original path.
|
|
* Therefore the directory referenced by the original path is
|
|
* the one that we are at. Consequently, we can let the result
|
|
* default to "success" regardless of whether the directory is
|
|
* empty. However, if there are any sub-file-systems, we will
|
|
* go on and store handles for them in the registry.
|
|
*/
|
|
res = OPENDIR_OK;
|
|
}
|
|
try {
|
|
for (File_system *fs = _first_file_system; fs; fs = fs->next) {
|
|
Vfs_handle *sub_dir_handle = nullptr;
|
|
|
|
Opendir_result r = fs->opendir(
|
|
sub_path, false, &sub_dir_handle, dir_vfs_handle.alloc());
|
|
|
|
switch (r) {
|
|
case OPENDIR_OK:
|
|
break;
|
|
case OPENDIR_ERR_OUT_OF_RAM:
|
|
case OPENDIR_ERR_OUT_OF_CAPS:
|
|
return r;
|
|
default:
|
|
continue;
|
|
}
|
|
|
|
new (dir_vfs_handle.alloc())
|
|
Dir_vfs_handle::Subdir_handle_element(
|
|
dir_vfs_handle.subdir_handle_registry, *sub_dir_handle);
|
|
/* return OK because at least one directory has been opened */
|
|
res = OPENDIR_OK;
|
|
}
|
|
}
|
|
catch (Genode::Out_of_ram) { res = OPENDIR_ERR_OUT_OF_RAM; }
|
|
catch (Genode::Out_of_caps) { res = OPENDIR_ERR_OUT_OF_CAPS; }
|
|
|
|
return res;
|
|
}
|
|
|
|
Opendir_result opendir(char const *path, bool create,
|
|
Vfs_handle **out_handle, Allocator &alloc) override
|
|
{
|
|
Opendir_result result = OPENDIR_OK;
|
|
|
|
if (_top_dir(path)) {
|
|
if (create)
|
|
return OPENDIR_ERR_PERMISSION_DENIED;
|
|
|
|
/*
|
|
* opendir with '/' (called from 'open_composite_dirs' returns handle
|
|
* only, VFS root additionally calls 'open_composite_dirs' in order to
|
|
* open its file systems
|
|
*/
|
|
Dir_vfs_handle *root_handle;
|
|
try {
|
|
root_handle = new (alloc)
|
|
Dir_vfs_handle(*this, *this, alloc, path);
|
|
}
|
|
catch (Genode::Out_of_ram) { return OPENDIR_ERR_OUT_OF_RAM; }
|
|
catch (Genode::Out_of_caps) { return OPENDIR_ERR_OUT_OF_CAPS; }
|
|
|
|
/* the VFS root may contain more file systems */
|
|
if (_vfs_root)
|
|
result = open_composite_dirs("/", *root_handle);
|
|
|
|
if (result == OPENDIR_OK) {
|
|
*out_handle = root_handle;
|
|
} else {
|
|
/* close the root handle and the rest will follow */
|
|
close(root_handle);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
char const *sub_path = _sub_path(path);
|
|
|
|
if (!sub_path)
|
|
return OPENDIR_ERR_LOOKUP_FAILED;
|
|
|
|
if (create) {
|
|
if (leaf_path(path) != nullptr)
|
|
return OPENDIR_ERR_NODE_ALREADY_EXISTS;
|
|
|
|
auto opendir_fn = [&] (File_system &fs, char const *path)
|
|
{
|
|
Vfs_handle *tmp_handle;
|
|
Opendir_result opendir_result =
|
|
fs.opendir(path, true, &tmp_handle, alloc);
|
|
if (opendir_result == OPENDIR_OK) {
|
|
tmp_handle->close();
|
|
}
|
|
return opendir_result; /* return from lambda */
|
|
};
|
|
|
|
Opendir_result opendir_result =
|
|
_dir_op(OPENDIR_ERR_LOOKUP_FAILED,
|
|
OPENDIR_ERR_PERMISSION_DENIED,
|
|
OPENDIR_OK,
|
|
path, opendir_fn);
|
|
|
|
if (opendir_result != OPENDIR_OK)
|
|
return opendir_result;
|
|
}
|
|
|
|
Dir_vfs_handle *dir_vfs_handle;
|
|
try {
|
|
dir_vfs_handle = new (alloc)
|
|
Dir_vfs_handle(*this, *this, alloc, path);
|
|
}
|
|
catch (Genode::Out_of_ram) { return OPENDIR_ERR_OUT_OF_RAM; }
|
|
catch (Genode::Out_of_caps) { return OPENDIR_ERR_OUT_OF_CAPS; }
|
|
|
|
/* path equals "/" (for reading the name of this directory) */
|
|
if (strlen(sub_path) == 0)
|
|
sub_path = "/";
|
|
|
|
result = open_composite_dirs(sub_path, *dir_vfs_handle);
|
|
if (result == OPENDIR_OK) {
|
|
*out_handle = dir_vfs_handle;
|
|
} else {
|
|
/* close the master handle and the rest will follow */
|
|
close(dir_vfs_handle);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
Openlink_result openlink(char const *path, bool create,
|
|
Vfs_handle **out_handle,
|
|
Allocator &alloc) override
|
|
{
|
|
auto openlink_fn = [&] (File_system &fs, char const *path)
|
|
{
|
|
return fs.openlink(path, create, out_handle, alloc);
|
|
};
|
|
|
|
return _dir_op(OPENLINK_ERR_LOOKUP_FAILED,
|
|
OPENLINK_ERR_PERMISSION_DENIED,
|
|
OPENLINK_OK,
|
|
path, openlink_fn);
|
|
}
|
|
|
|
void close(Vfs_handle *handle) override
|
|
{
|
|
if (handle && (&handle->ds() == this))
|
|
destroy(handle->alloc(), handle);
|
|
}
|
|
|
|
Watch_result watch(char const *path,
|
|
Vfs_watch_handle **handle,
|
|
Allocator &alloc) override
|
|
{
|
|
Watch_result res = WATCH_ERR_UNACCESSIBLE;
|
|
Dir_watch_handle *meta_handle = nullptr;
|
|
|
|
char const *sub_path = _sub_path(path);
|
|
if (!sub_path) return res;
|
|
|
|
for (File_system *fs = _first_file_system; fs; fs = fs->next) {
|
|
Vfs_watch_handle *sub_handle;
|
|
|
|
if (fs->watch(sub_path, &sub_handle, alloc) == WATCH_OK) {
|
|
if (meta_handle == nullptr) {
|
|
/* at least one non-static FS, allocate handle */
|
|
meta_handle = new (alloc) Dir_watch_handle(*this, alloc);
|
|
*handle = meta_handle;
|
|
res = WATCH_OK;
|
|
}
|
|
|
|
/* attach child FS handle to returned handle */
|
|
new (alloc)
|
|
Dir_watch_handle::Watch_handle_element(
|
|
meta_handle->handle_registry, *sub_handle);
|
|
}
|
|
}
|
|
|
|
return res;
|
|
}
|
|
|
|
void close(Vfs_watch_handle *handle) override
|
|
{
|
|
if (handle && (&handle->fs() == this))
|
|
destroy(handle->alloc(), handle);
|
|
}
|
|
|
|
Unlink_result unlink(char const *path) override
|
|
{
|
|
auto unlink_fn = [] (File_system &fs, char const *path)
|
|
{
|
|
return fs.unlink(path);
|
|
};
|
|
|
|
return _dir_op(UNLINK_ERR_NO_ENTRY, UNLINK_ERR_NO_PERM, UNLINK_OK,
|
|
path, unlink_fn);
|
|
}
|
|
|
|
Rename_result rename(char const *from_path, char const *to_path) override
|
|
{
|
|
from_path = _sub_path(from_path);
|
|
to_path = _sub_path(to_path);
|
|
|
|
/* path does not match directory name */
|
|
if (!from_path)
|
|
return RENAME_ERR_NO_ENTRY;
|
|
|
|
/*
|
|
* Cannot rename a path in the static VFS configuration.
|
|
*/
|
|
if (strlen(from_path) == 0)
|
|
return RENAME_ERR_NO_PERM;
|
|
|
|
/*
|
|
* Check if destination path resides within the same file
|
|
* system instance as the source path.
|
|
*/
|
|
if (!to_path)
|
|
return RENAME_ERR_CROSS_FS;
|
|
|
|
Rename_result final = RENAME_ERR_NO_ENTRY;
|
|
for (File_system *fs = _first_file_system; fs; fs = fs->next) {
|
|
switch (fs->rename(from_path, to_path)) {
|
|
case RENAME_OK: return RENAME_OK;
|
|
case RENAME_ERR_NO_ENTRY: continue;
|
|
case RENAME_ERR_NO_PERM: return RENAME_ERR_NO_PERM;
|
|
case RENAME_ERR_CROSS_FS: final = RENAME_ERR_CROSS_FS;
|
|
}
|
|
}
|
|
return final;
|
|
}
|
|
|
|
/***************************
|
|
** File_system interface **
|
|
***************************/
|
|
|
|
char const *name() const { return "dir"; }
|
|
char const *type() override { return "dir"; }
|
|
|
|
void apply_config(Genode::Xml_node const &node) override
|
|
{
|
|
using namespace Genode;
|
|
|
|
File_system *curr = _first_file_system;
|
|
for (unsigned i = 0; i < node.num_sub_nodes(); i++, curr = curr->next) {
|
|
Xml_node const &sub_node = node.sub_node(i);
|
|
|
|
/* check if type of XML node matches current file-system type */
|
|
if (sub_node.has_type(curr->type()) == false) {
|
|
Genode::error("VFS config update failed (node type '",
|
|
sub_node.type(), "' != fs type '", curr->type(),"')");
|
|
return;
|
|
}
|
|
|
|
curr->apply_config(node.sub_node(i));
|
|
}
|
|
}
|
|
|
|
|
|
/********************************
|
|
** File I/O service interface **
|
|
********************************/
|
|
|
|
Write_result write(Vfs_handle *, char const *, file_size, file_size &) override
|
|
{
|
|
return WRITE_ERR_INVALID;
|
|
}
|
|
|
|
bool queue_read(Vfs_handle *vfs_handle, file_size) override
|
|
{
|
|
Dir_vfs_handle *dir_vfs_handle =
|
|
static_cast<Dir_vfs_handle*>(vfs_handle);
|
|
|
|
if (_vfs_root)
|
|
return _queue_read_of_file_systems(dir_vfs_handle);
|
|
|
|
if (_top_dir(dir_vfs_handle->path.base()))
|
|
return true;
|
|
|
|
return _queue_read_of_file_systems(dir_vfs_handle);
|
|
}
|
|
|
|
Read_result complete_read(Vfs_handle *vfs_handle,
|
|
char *dst, file_size count,
|
|
file_size &out_count) override
|
|
{
|
|
out_count = 0;
|
|
|
|
if (count < sizeof(Dirent))
|
|
return READ_ERR_INVALID;
|
|
|
|
Dir_vfs_handle *dir_vfs_handle =
|
|
static_cast<Dir_vfs_handle*>(vfs_handle);
|
|
|
|
if (_vfs_root)
|
|
return _complete_read_of_file_systems(dir_vfs_handle, dst, count, out_count);
|
|
|
|
if (_top_dir(dir_vfs_handle->path.base())) {
|
|
|
|
Dirent &dirent = *(Dirent*)dst;
|
|
|
|
file_offset const index = vfs_handle->seek() / sizeof(Dirent);
|
|
|
|
if (index == 0) {
|
|
|
|
dirent = {
|
|
.fileno = 1,
|
|
.type = Dirent_type::DIRECTORY,
|
|
.rwx = Node_rwx::rwx(),
|
|
.name = { _name.string() }
|
|
};
|
|
|
|
} else {
|
|
|
|
dirent = {
|
|
.fileno = 0,
|
|
.type = Dirent_type::END,
|
|
.rwx = { },
|
|
.name = { }
|
|
};
|
|
}
|
|
|
|
out_count = sizeof(Dirent);
|
|
|
|
return READ_OK;
|
|
}
|
|
|
|
return _complete_read_of_file_systems(dir_vfs_handle, dst, count, out_count);
|
|
}
|
|
|
|
Ftruncate_result ftruncate(Vfs_handle *, file_size) override
|
|
{
|
|
return FTRUNCATE_ERR_NO_PERM;
|
|
}
|
|
|
|
bool read_ready(Vfs_handle *handle) override
|
|
{
|
|
if (&handle->fs() == this)
|
|
return true;
|
|
|
|
return handle->fs().read_ready(handle);
|
|
}
|
|
|
|
bool notify_read_ready(Vfs_handle *handle) override
|
|
{
|
|
if (&handle->fs() == this)
|
|
return true;
|
|
|
|
return handle->fs().notify_read_ready(handle);
|
|
}
|
|
|
|
bool queue_sync(Vfs_handle *vfs_handle) override
|
|
{
|
|
bool result = true;
|
|
|
|
Dir_vfs_handle *dir_vfs_handle =
|
|
static_cast<Dir_vfs_handle*>(vfs_handle);
|
|
|
|
auto f = [&result, dir_vfs_handle] (Dir_vfs_handle::Subdir_handle_element &e) {
|
|
/* forward the response handler */
|
|
dir_vfs_handle->apply_handler([&] (Io_response_handler &h) {
|
|
e.vfs_handle.handler(&h); });
|
|
e.synced = false;
|
|
|
|
if (!e.vfs_handle.fs().queue_sync(&e.vfs_handle)) {
|
|
result = false;
|
|
}
|
|
};
|
|
|
|
dir_vfs_handle->subdir_handle_registry.for_each(f);
|
|
|
|
return result;
|
|
}
|
|
|
|
Sync_result complete_sync(Vfs_handle *vfs_handle) override
|
|
{
|
|
Sync_result result = SYNC_OK;
|
|
|
|
Dir_vfs_handle *dir_vfs_handle =
|
|
static_cast<Dir_vfs_handle*>(vfs_handle);
|
|
|
|
auto f = [&result] (Dir_vfs_handle::Subdir_handle_element &e) {
|
|
if (e.synced)
|
|
return;
|
|
|
|
Sync_result r = e.vfs_handle.fs().complete_sync(&e.vfs_handle);
|
|
if (r != SYNC_OK)
|
|
result = r;
|
|
else
|
|
e.synced = true;
|
|
};
|
|
|
|
dir_vfs_handle->subdir_handle_registry.for_each(f);
|
|
|
|
return result;
|
|
}
|
|
};
|
|
|
|
#endif /* _INCLUDE__VFS__DIR_FILE_SYSTEM_H_ */
|