ExternalVendorCode/genode
1
0
Fork 0
mirror of https://github.com/genodelabs/genode.git synced 2025-04-07 03:17:44 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

ram_fs: coding style, license headers

Browse Source 
Issue #1635
This commit is contained in:
Norman Feske 2015-07-22 15:54:22 +02:00 committed by Christian Helmuth
parent f996697fd5
commit 1feaf75605
5 changed files with 714 additions and 682 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

759
repos/os/include/ram_fs/chunk.h
View File

@ -5,7 +5,7 @@
*/
/*
* Copyright (C) 2012-2013 Genode Labs GmbH
* Copyright (C) 2012-2015 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU General Public License version 2.
@ -22,420 +22,425 @@
namespace File_system {
using namespace Genode;
using Genode::Noncopyable;
class Chunk_base;
template <unsigned> class Chunk;
template <unsigned, typename> class Chunk_index;
}
/**
* Common base class of both 'Chunk' and 'Chunk_index'
*/
class Chunk_base : Noncopyable
{
public:
/**
* Common base class of both 'Chunk' and 'Chunk_index'
*/
class File_system::Chunk_base : Noncopyable
{
public:
class Index_out_of_range { };
class Index_out_of_range { };
protected:
protected:
seek_off_t const _base_offset;
size_t _num_entries; /* corresponds to last used entry */
seek_off_t const _base_offset;
size_t _num_entries; /* corresponds to last used entry */
/**
* Test if specified range lies within the chunk
/**
* Test if specified range lies within the chunk
*/
void assert_valid_range(seek_off_t start, size_t len,
file_size_t chunk_size) const
{
if (is_zero()) return;
if (start < _base_offset)
throw Index_out_of_range();
if (start + len > _base_offset + chunk_size)
throw Index_out_of_range();
}
Chunk_base(seek_off_t base_offset)
: _base_offset(base_offset), _num_entries(0) { }
/**
* Construct zero chunk
*
* A zero chunk is a chunk that cannot be written to. When reading
* from it, it returns zeros. Because there is a single zero chunk
* for each chunk type, the base offset is meaningless. We use a
* base offset of ~0 as marker to identify zero chunks.
*/
Chunk_base() : _base_offset(~0L), _num_entries(0) { }
public:
/**
* Return absolute base offset of chunk in bytes
*/
seek_off_t base_offset() const { return _base_offset; }
/**
* Return true if chunk is a read-only zero chunk
*/
bool is_zero() const { return _base_offset == (seek_off_t)(~0L); }
/**
* Return true if chunk has no allocated sub chunks
*/
bool empty() const { return _num_entries == 0; }
};
/**
* Chunk of bytes used as leaf in hierarchy of chunk indices
*/
template <unsigned CHUNK_SIZE>
class File_system::Chunk : public Chunk_base
{
private:
char _data[CHUNK_SIZE];
public:
enum { SIZE = CHUNK_SIZE };
/**
* Construct byte chunk
*
* \param base_offset absolute offset of chunk in bytes
*
* The first argument is unused. Its mere purpose is to make the
* signature of the constructor compatible to the constructor
* of 'Chunk_index'.
*/
Chunk(Allocator &, seek_off_t base_offset)
:
Chunk_base(base_offset)
{
memset(_data, 0, CHUNK_SIZE);
}
/**
* Construct zero chunk
*/
Chunk() { }
/**
* Return number of used entries
*
* The returned value corresponds to the index of the last used
* entry + 1. It does not correlate to the number of actually
* allocated entries (there may be ranges of zero blocks).
*/
file_size_t used_size() const { return _num_entries; }
void write(char const *src, size_t len, seek_off_t seek_offset)
{
assert_valid_range(seek_offset, len, SIZE);
/* offset relative to this chunk */
seek_off_t const local_offset = seek_offset - base_offset();
memcpy(&_data[local_offset], src, len);
_num_entries = max(_num_entries, local_offset + len);
}
void read(char *dst, size_t len, seek_off_t seek_offset) const
{
assert_valid_range(seek_offset, len, SIZE);
memcpy(dst, &_data[seek_offset - base_offset()], len);
}
void truncate(file_size_t size)
{
assert_valid_range(size, 0, SIZE);
/*
* Offset of the first free position (relative to the beginning
* this chunk).
*/
void assert_valid_range(seek_off_t start, size_t len,
file_size_t chunk_size) const
{
if (is_zero()) return;
seek_off_t const local_offset = size - base_offset();
if (start < _base_offset)
throw Index_out_of_range();
if (local_offset >= _num_entries)
return;
if (start + len > _base_offset + chunk_size)
throw Index_out_of_range();
}
memset(&_data[local_offset], 0, _num_entries - local_offset);
Chunk_base(seek_off_t base_offset)
: _base_offset(base_offset), _num_entries(0) { }
_num_entries = local_offset;
}
};
/**
* Construct zero chunk
*
* A zero chunk is a chunk that cannot be written to. When reading
* from it, it returns zeros. Because there is a single zero chunk
* for each chunk type, the base offset is meaningless. We use a
* base offset of ~0 as marker to identify zero chunks.
template <unsigned NUM_ENTRIES, typename ENTRY_TYPE>
class File_system::Chunk_index : public Chunk_base
{
public:
typedef ENTRY_TYPE Entry;
enum { ENTRY_SIZE = ENTRY_TYPE::SIZE,
SIZE = ENTRY_SIZE*NUM_ENTRIES };
private:
Allocator &_alloc;
Entry * _entries[NUM_ENTRIES];
/**
* Return instance of a zero sub chunk
*/
static Entry const &_zero_chunk()
{
static Entry zero_chunk;
return zero_chunk;
}
/**
* Return sub chunk at given index
*
* If there is no sub chunk at the specified index, this function
* transparently allocates one. Hence, the returned sub chunk
* is ready to be written to.
*/
Entry &_entry_for_writing(unsigned index)
{
if (index >= NUM_ENTRIES)
throw Index_out_of_range();
if (_entries[index])
return *_entries[index];
seek_off_t entry_offset = base_offset() + index*ENTRY_SIZE;
_entries[index] = new (&_alloc) Entry(_alloc, entry_offset);
_num_entries = max(_num_entries, index + 1);
return *_entries[index];
}
/**
* Return sub chunk at given index (for reading only)
*
* This function transparently provides a zero sub chunk for any
* index that is not populated by a real chunk.
*/
Entry const &_entry_for_reading(unsigned index) const
{
if (index >= NUM_ENTRIES)
throw Index_out_of_range();
if (_entries[index])
return *_entries[index];
return _zero_chunk();
}
/**
* Return index of entry located at specified byte offset
*
* The caller of this function must make sure that the offset
* parameter is within the bounds of the chunk.
*/
unsigned _index_by_offset(seek_off_t offset) const
{
return (offset - base_offset()) / ENTRY_SIZE;
}
/**
* Apply operation 'func' to a range of entries
*/
template <typename THIS, typename DATA, typename FUNC>
static void _range_op(THIS &obj, DATA *data, size_t len,
seek_off_t seek_offset, FUNC const &func)
{
/*
* Depending on whether this function is called for reading
* (const function) or writing (non-const function), the
* operand type is const or non-const Entry. The correct type
* is embedded as a trait in the 'FUNC' functor type.
*/
Chunk_base() : _base_offset(~0L), _num_entries(0) { }
typedef typename FUNC::Entry Const_qualified_entry;
public:
obj.assert_valid_range(seek_offset, len, SIZE);
/**
* Return absolute base offset of chunk in bytes
*/
seek_off_t base_offset() const { return _base_offset; }
while (len > 0) {
/**
* Return true if chunk is a read-only zero chunk
*/
bool is_zero() const { return _base_offset == (seek_off_t)(~0L); }
unsigned const index = obj._index_by_offset(seek_offset);
/**
* Return true if chunk has no allocated sub chunks
*/
bool empty() const { return _num_entries == 0; }
};
/**
* Chunk of bytes used as leaf in hierarchy of chunk indices
*/
template <unsigned CHUNK_SIZE>
class Chunk : public Chunk_base
{
private:
char _data[CHUNK_SIZE];
public:
enum { SIZE = CHUNK_SIZE };
/**
* Construct byte chunk
*
* \param base_offset absolute offset of chunk in bytes
*
* The first argument is unused. Its mere purpose is to make the
* signature of the constructor compatible to the constructor
* of 'Chunk_index'.
*/
Chunk(Allocator &, seek_off_t base_offset)
:
Chunk_base(base_offset)
{
memset(_data, 0, CHUNK_SIZE);
}
/**
* Construct zero chunk
*/
Chunk() { }
/**
* Return number of used entries
*
* The returned value corresponds to the index of the last used
* entry + 1. It does not correlate to the number of actually
* allocated entries (there may be ranges of zero blocks).
*/
file_size_t used_size() const { return _num_entries; }
void write(char const *src, size_t len, seek_off_t seek_offset)
{
assert_valid_range(seek_offset, len, SIZE);
/* offset relative to this chunk */
seek_off_t const local_offset = seek_offset - base_offset();
memcpy(&_data[local_offset], src, len);
_num_entries = max(_num_entries, local_offset + len);
}
void read(char *dst, size_t len, seek_off_t seek_offset) const
{
assert_valid_range(seek_offset, len, SIZE);
memcpy(dst, &_data[seek_offset - base_offset()], len);
}
void truncate(file_size_t size)
{
assert_valid_range(size, 0, SIZE);
Const_qualified_entry &entry = FUNC::lookup(obj, index);
/*
* Offset of the first free position (relative to the beginning
* this chunk).
* Calculate byte offset relative to the chunk
*
* We cannot use 'entry.base_offset()' for this calculation
* because in the const case, the lookup might return a
* zero chunk, which has no defined base offset. Therefore,
* we calculate the base offset via index*ENTRY_SIZE.
*/
seek_off_t const local_offset = size - base_offset();
seek_off_t const local_seek_offset =
seek_offset - obj.base_offset() - index*ENTRY_SIZE;
if (local_offset >= _num_entries)
return;
/* available capacity at 'entry' starting at seek offset */
seek_off_t const capacity = ENTRY_SIZE - local_seek_offset;
seek_off_t const curr_len = min(len, capacity);
memset(&_data[local_offset], 0, _num_entries - local_offset);
/* apply functor (read or write) to entry */
func(entry, data, curr_len, seek_offset);
_num_entries = local_offset;
/* advance to next entry */
len -= curr_len;
data += curr_len;
seek_offset += curr_len;
}
};
template <unsigned NUM_ENTRIES, typename ENTRY_TYPE>
class Chunk_index : public Chunk_base
{
public:
}
struct Write_func
{
typedef ENTRY_TYPE Entry;
enum { ENTRY_SIZE = ENTRY_TYPE::SIZE,
SIZE = ENTRY_SIZE*NUM_ENTRIES };
static Entry &lookup(Chunk_index &chunk, unsigned i) {
return chunk._entry_for_writing(i); }
private:
Allocator &_alloc;
Entry * _entries[NUM_ENTRIES];
/**
* Return instance of a zero sub chunk
*/
static Entry const &_zero_chunk()
void operator () (Entry &entry, char const *src, size_t len,
seek_off_t seek_offset) const
{
static Entry zero_chunk;
return zero_chunk;
entry.write(src, len, seek_offset);
}
};
/**
* Return sub chunk at given index
*
* If there is no sub chunk at the specified index, this function
* transparently allocates one. Hence, the returned sub chunk
* is ready to be written to.
*/
Entry &_entry_for_writing(unsigned index)
struct Read_func
{
typedef ENTRY_TYPE const Entry;
static Entry &lookup(Chunk_index const &chunk, unsigned i) {
return chunk._entry_for_reading(i); }
void operator () (Entry &entry, char *dst, size_t len,
seek_off_t seek_offset) const
{
if (index >= NUM_ENTRIES)
throw Index_out_of_range();
if (_entries[index])
return *_entries[index];
seek_off_t entry_offset = base_offset() + index*ENTRY_SIZE;
_entries[index] = new (&_alloc) Entry(_alloc, entry_offset);
_num_entries = max(_num_entries, index + 1);
return *_entries[index];
if (entry.is_zero())
memset(dst, 0, len);
else
entry.read(dst, len, seek_offset);
}
};
/**
* Return sub chunk at given index (for reading only)
*
* This function transparently provides a zero sub chunk for any
* index that is not populated by a real chunk.
*/
Entry const &_entry_for_reading(unsigned index) const
{
if (index >= NUM_ENTRIES)
throw Index_out_of_range();
void _init_entries()
{
for (unsigned i = 0; i < NUM_ENTRIES; i++)
_entries[i] = 0;
}
if (_entries[index])
return *_entries[index];
return _zero_chunk();
void _destroy_entry(unsigned i)
{
if (_entries[i] && (i < _num_entries)) {
destroy(&_alloc, _entries[i]);
_entries[i] = 0;
}
}
/**
* Return index of entry located at specified byte offset
*
* The caller of this function must make sure that the offset
* parameter is within the bounds of the chunk.
public:
/**
* Constructor
*
* \param alloc allocator to use for allocating sub-chunk
* indices and chunks
* \param base_offset absolute offset of the chunk in bytes
*/
Chunk_index(Allocator &alloc, seek_off_t base_offset)
: Chunk_base(base_offset), _alloc(alloc) { _init_entries(); }
/**
* Construct zero chunk
*/
Chunk_index() : _alloc(*(Allocator *)0) { }
/**
* Destructor
*/
~Chunk_index()
{
for (unsigned i = 0; i < NUM_ENTRIES; i++)
_destroy_entry(i);
}
/**
* Return size of chunk in bytes
*
* The returned value corresponds to the position after the highest
* offset that was written to.
*/
file_size_t used_size() const
{
if (_num_entries == 0)
return 0;
/* size of entries that lie completely within the used range */
file_size_t const size_whole_entries = ENTRY_SIZE*(_num_entries - 1);
Entry *last_entry = _entries[_num_entries - 1];
if (!last_entry)
return size_whole_entries;
return size_whole_entries + last_entry->used_size();
}
/**
* Write data to chunk
*/
void write(char const *src, size_t len, seek_off_t seek_offset)
{
_range_op(*this, src, len, seek_offset, Write_func());
}
/**
* Read data from chunk
*/
void read(char *dst, size_t len, seek_off_t seek_offset) const
{
_range_op(*this, dst, len, seek_offset, Read_func());
}
/**
* Truncate chunk to specified size in bytes
*
* This function can be used to shrink a chunk only. Specifying a
* 'size' larger than 'used_size' has no effect. The value returned
* by 'used_size' refers always to the position of the last byte
* written to the chunk.
*/
void truncate(file_size_t size)
{
unsigned const trunc_index = _index_by_offset(size);
if (trunc_index >= _num_entries)
return;
for (unsigned i = trunc_index + 1; i < _num_entries; i++)
_destroy_entry(i);
/* traverse into sub chunks */
if (_entries[trunc_index])
_entries[trunc_index]->truncate(size);
_num_entries = trunc_index + 1;
/*
* If the truncated at a chunk boundary, we can release the
* empty trailing chunk at 'trunc_index'.
*/
unsigned _index_by_offset(seek_off_t offset) const
{
return (offset - base_offset()) / ENTRY_SIZE;
if (_entries[trunc_index] && _entries[trunc_index]->empty()) {
_destroy_entry(trunc_index);
_num_entries--;
}
/**
* Apply operation 'func' to a range of entries
*/
template <typename THIS, typename DATA, typename FUNC>
static void _range_op(THIS &obj, DATA *data, size_t len,
seek_off_t seek_offset, FUNC const &func)
{
/*
* Depending on whether this function is called for reading
* (const function) or writing (non-const function), the
* operand type is const or non-const Entry. The correct type
* is embedded as a trait in the 'FUNC' functor type.
*/
typedef typename FUNC::Entry Const_qualified_entry;
obj.assert_valid_range(seek_offset, len, SIZE);
while (len > 0) {
unsigned const index = obj._index_by_offset(seek_offset);
Const_qualified_entry &entry = FUNC::lookup(obj, index);
/*
* Calculate byte offset relative to the chunk
*
* We cannot use 'entry.base_offset()' for this calculation
* because in the const case, the lookup might return a
* zero chunk, which has no defined base offset. Therefore,
* we calculate the base offset via index*ENTRY_SIZE.
*/
seek_off_t const local_seek_offset =
seek_offset - obj.base_offset() - index*ENTRY_SIZE;
/* available capacity at 'entry' starting at seek offset */
seek_off_t const capacity = ENTRY_SIZE - local_seek_offset;
seek_off_t const curr_len = min(len, capacity);
/* apply functor (read or write) to entry */
func(entry, data, curr_len, seek_offset);
/* advance to next entry */
len -= curr_len;
data += curr_len;
seek_offset += curr_len;
}
}
struct Write_func
{
typedef ENTRY_TYPE Entry;
static Entry &lookup(Chunk_index &chunk, unsigned i) {
return chunk._entry_for_writing(i); }
void operator () (Entry &entry, char const *src, size_t len,
seek_off_t seek_offset) const
{
entry.write(src, len, seek_offset);
}
};
struct Read_func
{
typedef ENTRY_TYPE const Entry;
static Entry &lookup(Chunk_index const &chunk, unsigned i) {
return chunk._entry_for_reading(i); }
void operator () (Entry &entry, char *dst, size_t len,
seek_off_t seek_offset) const
{
if (entry.is_zero())
memset(dst, 0, len);
else
entry.read(dst, len, seek_offset);
}
};
void _init_entries()
{
for (unsigned i = 0; i < NUM_ENTRIES; i++)
_entries[i] = 0;
}
void _destroy_entry(unsigned i)
{
if (_entries[i] && (i < _num_entries)) {
destroy(&_alloc, _entries[i]);
_entries[i] = 0;
}
}
public:
/**
* Constructor
*
* \param alloc allocator to use for allocating sub-chunk
* indices and chunks
* \param base_offset absolute offset of the chunk in bytes
*/
Chunk_index(Allocator &alloc, seek_off_t base_offset)
: Chunk_base(base_offset), _alloc(alloc) { _init_entries(); }
/**
* Construct zero chunk
*/
Chunk_index() : _alloc(*(Allocator *)0) { }
/**
* Destructor
*/
~Chunk_index()
{
for (unsigned i = 0; i < NUM_ENTRIES; i++)
_destroy_entry(i);
}
/**
* Return size of chunk in bytes
*
* The returned value corresponds to the position after the highest
* offset that was written to.
*/
file_size_t used_size() const
{
if (_num_entries == 0)
return 0;
/* size of entries that lie completely within the used range */
file_size_t const size_whole_entries = ENTRY_SIZE*(_num_entries - 1);
Entry *last_entry = _entries[_num_entries - 1];
if (!last_entry)
return size_whole_entries;
return size_whole_entries + last_entry->used_size();
}
/**
* Write data to chunk
*/
void write(char const *src, size_t len, seek_off_t seek_offset)
{
_range_op(*this, src, len, seek_offset, Write_func());
}
/**
* Read data from chunk
*/
void read(char *dst, size_t len, seek_off_t seek_offset) const
{
_range_op(*this, dst, len, seek_offset, Read_func());
}
/**
* Truncate chunk to specified size in bytes
*
* This function can be used to shrink a chunk only. Specifying a
* 'size' larger than 'used_size' has no effect. The value returned
* by 'used_size' refers always to the position of the last byte
* written to the chunk.
*/
void truncate(file_size_t size)
{
unsigned const trunc_index = _index_by_offset(size);
if (trunc_index >= _num_entries)
return;
for (unsigned i = trunc_index + 1; i < _num_entries; i++)
_destroy_entry(i);
/* traverse into sub chunks */
if (_entries[trunc_index])
_entries[trunc_index]->truncate(size);
_num_entries = trunc_index + 1;
/*
* If the truncated at a chunk boundary, we can release the
* empty trailing chunk at 'trunc_index'.
*/
if (_entries[trunc_index] && _entries[trunc_index]->empty()) {
_destroy_entry(trunc_index);
_num_entries--;
}
}
};
}
};
#endif /* _INCLUDE__RAM_FS__CHUNK_H_ */

373
repos/os/include/ram_fs/directory.h
View File

@ -4,6 +4,13 @@
* \date 2012-04-11
*/
/*
* Copyright (C) 2011-2015 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU General Public License version 2.
*/
#ifndef _INCLUDE__RAM_FS__DIRECTORY_H_
#define _INCLUDE__RAM_FS__DIRECTORY_H_
@ -15,207 +22,207 @@
#include <ram_fs/file.h>
#include <ram_fs/symlink.h>
namespace File_system {
namespace File_system { class Directory; }
class Directory : public Node
{
private:
List<Node> _entries;
size_t _num_entries;
class File_system::Directory : public Node
{
private:
public:
List<Node> _entries;
size_t _num_entries;
Directory(char const *name) : _num_entries(0) { Node::name(name); }
public:
Node *entry_unsynchronized(size_t index)
{
Node *node = _entries.first();
for (unsigned i = 0; i < index && node; node = node->next(), i++);
return node;
}
Directory(char const *name) : _num_entries(0) { Node::name(name); }
bool has_sub_node_unsynchronized(char const *name) const
{
Node const *sub_node = _entries.first();
for (; sub_node; sub_node = sub_node->next())
if (strcmp(sub_node->name(), name) == 0)
return true;
Node *entry_unsynchronized(size_t index)
{
Node *node = _entries.first();
for (unsigned i = 0; i < index && node; node = node->next(), i++);
return node;
}
return false;
}
bool has_sub_node_unsynchronized(char const *name) const
{
Node const *sub_node = _entries.first();
for (; sub_node; sub_node = sub_node->next())
if (strcmp(sub_node->name(), name) == 0)
return true;
void adopt_unsynchronized(Node *node)
{
/*
* XXX inc ref counter
*/
_entries.insert(node);
_num_entries++;
return false;
}
mark_as_updated();
}
void discard_unsynchronized(Node *node)
{
_entries.remove(node);
_num_entries--;
mark_as_updated();
}
Node *lookup_and_lock(char const *path, bool return_parent = false)
{
if (strcmp(path, "") == 0) {
lock();
return this;
}
if (!path || path[0] == '/')
throw Lookup_failed();
/* find first path delimiter */
unsigned i = 0;
for (; path[i] && path[i] != '/'; i++);
/*
* If no path delimiter was found, we are the parent of the
* specified path.
*/
if (path[i] == 0 && return_parent) {
lock();
return this;
}
/*
* The offset 'i' corresponds to the end of the first path
* element, which can be either the end of the string or the
* first '/' character.
*/
/* try to find entry that matches the first path element */
Node *sub_node = _entries.first();
for (; sub_node; sub_node = sub_node->next())
if ((strlen(sub_node->name()) == i) &&
(strcmp(sub_node->name(), path, i) == 0))
break;
if (!sub_node)
throw Lookup_failed();
if (is_basename(path)) {
/*
* Because 'path' is a basename that corresponds to an
* existing sub_node, we have found what we were looking
* for.
*/
sub_node->lock();
return sub_node;
}
/*
* As 'path' contains one or more path delimiters, traverse
* into the sub directory names after the first path element.
*/
/*
* We cannot traverse into anything other than a directory.
*
* XXX we might follow symlinks here
*/
Directory *sub_dir = dynamic_cast<Directory *>(sub_node);
if (!sub_dir)
throw Lookup_failed();
return sub_dir->lookup_and_lock(path + i + 1, return_parent);
}
Directory *lookup_and_lock_dir(char const *path)
{
Node *node = lookup_and_lock(path);
Directory *dir = dynamic_cast<Directory *>(node);
if (dir)
return dir;
node->unlock();
throw Lookup_failed();
}
File *lookup_and_lock_file(char const *path)
{
Node *node = lookup_and_lock(path);
File *file = dynamic_cast<File *>(node);
if (file)
return file;
node->unlock();
throw Lookup_failed();
}
Symlink *lookup_and_lock_symlink(char const *path)
{
Node *node = lookup_and_lock(path);
Symlink *symlink = dynamic_cast<Symlink *>(node);
if (symlink)
return symlink;
node->unlock();
throw Lookup_failed();
}
/**
* Lookup parent directory of the specified path
*
* \throw Lookup_failed
void adopt_unsynchronized(Node *node)
{
/*
* XXX inc ref counter
*/
Directory *lookup_and_lock_parent(char const *path)
{
return static_cast<Directory *>(lookup_and_lock(path, true));
_entries.insert(node);
_num_entries++;
mark_as_updated();
}
void discard_unsynchronized(Node *node)
{
_entries.remove(node);
_num_entries--;
mark_as_updated();
}
Node *lookup_and_lock(char const *path, bool return_parent = false)
{
if (strcmp(path, "") == 0) {
lock();
return this;
}
size_t read(char *dst, size_t len, seek_off_t seek_offset)
{
if (len < sizeof(Directory_entry)) {
PERR("read buffer too small for directory entry");
return 0;
}
if (!path || path[0] == '/')
throw Lookup_failed();
seek_off_t index = seek_offset / sizeof(Directory_entry);
/* find first path delimiter */
unsigned i = 0;
for (; path[i] && path[i] != '/'; i++);
if (seek_offset % sizeof(Directory_entry)) {
PERR("seek offset not alighed to sizeof(Directory_entry)");
return 0;
}
Node *node = entry_unsynchronized(index);
/* index out of range */
if (!node)
return 0;
Directory_entry *e = (Directory_entry *)(dst);
if (dynamic_cast<File *>(node)) e->type = Directory_entry::TYPE_FILE;
if (dynamic_cast<Directory *>(node)) e->type = Directory_entry::TYPE_DIRECTORY;
if (dynamic_cast<Symlink *>(node)) e->type = Directory_entry::TYPE_SYMLINK;
strncpy(e->name, node->name(), sizeof(e->name));
return sizeof(Directory_entry);
/*
* If no path delimiter was found, we are the parent of the
* specified path.
*/
if (path[i] == 0 && return_parent) {
lock();
return this;
}
size_t write(char const *src, size_t len, seek_off_t seek_offset)
{
/* writing to directory nodes is not supported */
/*
* The offset 'i' corresponds to the end of the first path
* element, which can be either the end of the string or the
* first '/' character.
*/
/* try to find entry that matches the first path element */
Node *sub_node = _entries.first();
for (; sub_node; sub_node = sub_node->next())
if ((strlen(sub_node->name()) == i) &&
(strcmp(sub_node->name(), path, i) == 0))
break;
if (!sub_node)
throw Lookup_failed();
if (is_basename(path)) {
/*
* Because 'path' is a basename that corresponds to an
* existing sub_node, we have found what we were looking
* for.
*/
sub_node->lock();
return sub_node;
}
/*
* As 'path' contains one or more path delimiters, traverse
* into the sub directory names after the first path element.
*/
/*
* We cannot traverse into anything other than a directory.
*
* XXX we might follow symlinks here
*/
Directory *sub_dir = dynamic_cast<Directory *>(sub_node);
if (!sub_dir)
throw Lookup_failed();
return sub_dir->lookup_and_lock(path + i + 1, return_parent);
}
Directory *lookup_and_lock_dir(char const *path)
{
Node *node = lookup_and_lock(path);
Directory *dir = dynamic_cast<Directory *>(node);
if (dir)
return dir;
node->unlock();
throw Lookup_failed();
}
File *lookup_and_lock_file(char const *path)
{
Node *node = lookup_and_lock(path);
File *file = dynamic_cast<File *>(node);
if (file)
return file;
node->unlock();
throw Lookup_failed();
}
Symlink *lookup_and_lock_symlink(char const *path)
{
Node *node = lookup_and_lock(path);
Symlink *symlink = dynamic_cast<Symlink *>(node);
if (symlink)
return symlink;
node->unlock();
throw Lookup_failed();
}
/**
* Lookup parent directory of the specified path
*
* \throw Lookup_failed
*/
Directory *lookup_and_lock_parent(char const *path)
{
return static_cast<Directory *>(lookup_and_lock(path, true));
}
size_t read(char *dst, size_t len, seek_off_t seek_offset)
{
if (len < sizeof(Directory_entry)) {
PERR("read buffer too small for directory entry");
return 0;
}
size_t num_entries() const { return _num_entries; }
};
}
seek_off_t index = seek_offset / sizeof(Directory_entry);
if (seek_offset % sizeof(Directory_entry)) {
PERR("seek offset not alighed to sizeof(Directory_entry)");
return 0;
}
Node *node = entry_unsynchronized(index);
/* index out of range */
if (!node)
return 0;
Directory_entry *e = (Directory_entry *)(dst);
if (dynamic_cast<File *>(node)) e->type = Directory_entry::TYPE_FILE;
if (dynamic_cast<Directory *>(node)) e->type = Directory_entry::TYPE_DIRECTORY;
if (dynamic_cast<Symlink *>(node)) e->type = Directory_entry::TYPE_SYMLINK;
strncpy(e->name, node->name(), sizeof(e->name));
return sizeof(Directory_entry);
}
size_t write(char const *src, size_t len, seek_off_t seek_offset)
{
/* writing to directory nodes is not supported */
return 0;
}
size_t num_entries() const { return _num_entries; }
};
#endif /* _INCLUDE__RAM_FS__DIRECTORY_H_ */

139
repos/os/include/ram_fs/file.h
View File

@ -4,6 +4,13 @@
* \date 2012-04-11
*/
/*
* Copyright (C) 2012-2015 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU General Public License version 2.
*/
#ifndef _INCLUDE__RAM_FS__FILE_H_
#define _INCLUDE__RAM_FS__FILE_H_
@ -14,93 +21,93 @@
#include <ram_fs/node.h>
#include <ram_fs/chunk.h>
namespace File_system {
namespace File_system { class File; }
class File : public Node
{
private:
typedef Chunk<4096> Chunk_level_3;
typedef Chunk_index<128, Chunk_level_3> Chunk_level_2;
typedef Chunk_index<64, Chunk_level_2> Chunk_level_1;
typedef Chunk_index<64, Chunk_level_1> Chunk_level_0;
class File_system::File : public Node
{
private:
Chunk_level_0 _chunk;
typedef Chunk<4096> Chunk_level_3;
typedef Chunk_index<128, Chunk_level_3> Chunk_level_2;
typedef Chunk_index<64, Chunk_level_2> Chunk_level_1;
typedef Chunk_index<64, Chunk_level_1> Chunk_level_0;
file_size_t _length;
Chunk_level_0 _chunk;
public:
file_size_t _length;
File(Allocator &alloc, char const *name)
: _chunk(alloc, 0), _length(0) { Node::name(name); }
public:
size_t read(char *dst, size_t len, seek_off_t seek_offset)
{
file_size_t const chunk_used_size = _chunk.used_size();
File(Allocator &alloc, char const *name)
: _chunk(alloc, 0), _length(0) { Node::name(name); }
if (seek_offset >= _length)
return 0;
size_t read(char *dst, size_t len, seek_off_t seek_offset)
{
file_size_t const chunk_used_size = _chunk.used_size();
/*
* Constrain read transaction to available chunk data
*
* Note that 'chunk_used_size' may be lower than '_length'
* because 'Chunk' may have truncated tailing zeros.
*/
if (seek_offset + len >= _length)
len = _length - seek_offset;
if (seek_offset >= _length)
return 0;
file_size_t read_len = len;
/*
* Constrain read transaction to available chunk data
*
* Note that 'chunk_used_size' may be lower than '_length'
* because 'Chunk' may have truncated tailing zeros.
*/
if (seek_offset + len >= _length)
len = _length - seek_offset;
if (seek_offset + read_len > chunk_used_size) {
if (chunk_used_size >= seek_offset)
read_len = chunk_used_size - seek_offset;
else
read_len = 0;
}
file_size_t read_len = len;
_chunk.read(dst, read_len, seek_offset);
/* add zero padding if needed */
if (read_len < len)
memset(dst + read_len, 0, len - read_len);
return len;
if (seek_offset + read_len > chunk_used_size) {
if (chunk_used_size >= seek_offset)
read_len = chunk_used_size - seek_offset;
else
read_len = 0;
}
size_t write(char const *src, size_t len, seek_off_t seek_offset)
{
if (seek_offset == (seek_off_t)(~0))
seek_offset = _chunk.used_size();
_chunk.read(dst, read_len, seek_offset);
if (seek_offset + len >= Chunk_level_0::SIZE)
throw Size_limit_reached();
/* add zero padding if needed */
if (read_len < len)
memset(dst + read_len, 0, len - read_len);
_chunk.write(src, len, (size_t)seek_offset);
return len;
}
/*
* Keep track of file length. We cannot use 'chunk.used_size()'
* as file length because trailing zeros may by represented
* by zero chunks, which do not contribute to 'used_size()'.
*/
_length = max(_length, seek_offset + len);
size_t write(char const *src, size_t len, seek_off_t seek_offset)
{
if (seek_offset == (seek_off_t)(~0))
seek_offset = _chunk.used_size();
mark_as_updated();
return len;
}
if (seek_offset + len >= Chunk_level_0::SIZE)
throw Size_limit_reached();
file_size_t length() const { return _length; }
_chunk.write(src, len, (size_t)seek_offset);
void truncate(file_size_t size)
{
if (size < _chunk.used_size())
_chunk.truncate(size);
/*
* Keep track of file length. We cannot use 'chunk.used_size()'
* as file length because trailing zeros may by represented
* by zero chunks, which do not contribute to 'used_size()'.
*/
_length = max(_length, seek_offset + len);
_length = size;
mark_as_updated();
return len;
}
mark_as_updated();
}
};
}
file_size_t length() const { return _length; }
void truncate(file_size_t size)
{
if (size < _chunk.used_size())
_chunk.truncate(size);
_length = size;
mark_as_updated();
}
};
#endif /* _INCLUDE__RAM_FS__FILE_H_ */

68
repos/os/include/ram_fs/node.h
View File

@ -4,6 +4,13 @@
* \date 2012-04-11
*/
/*
* Copyright (C) 2012-2015 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU General Public License version 2.
*/
#ifndef _INCLUDE__RAM_FS__NODE_H_
#define _INCLUDE__RAM_FS__NODE_H_
@ -12,47 +19,46 @@
#include <file_system/node.h>
#include <util/list.h>
namespace File_system {
namespace File_system { class Node; }
class Node : public Node_base, public List<Node>::Element
{
public:
typedef char Name[128];
class File_system::Node : public Node_base, public List<Node>::Element
{
public:
private:
typedef char Name[128];
int _ref_count;
Name _name;
unsigned long const _inode;
private:
/**
* Generate unique inode number
*/
static unsigned long _unique_inode()
{
static unsigned long inode_count;
return ++inode_count;
}
int _ref_count;
Name _name;
unsigned long const _inode;
public:
/**
* Generate unique inode number
*/
static unsigned long _unique_inode()
{
static unsigned long inode_count;
return ++inode_count;
}
Node()
: _ref_count(0), _inode(_unique_inode())
{ _name[0] = 0; }
public:
unsigned long inode() const { return _inode; }
char const *name() const { return _name; }
Node()
: _ref_count(0), _inode(_unique_inode())
{ _name[0] = 0; }
/**
* Assign name
*/
void name(char const *name) { strncpy(_name, name, sizeof(_name)); }
unsigned long inode() const { return _inode; }
char const *name() const { return _name; }
virtual size_t read(char *dst, size_t len, seek_off_t) = 0;
virtual size_t write(char const *src, size_t len, seek_off_t) = 0;
};
/**
* Assign name
*/
void name(char const *name) { strncpy(_name, name, sizeof(_name)); }
}
virtual size_t read(char *dst, size_t len, seek_off_t) = 0;
virtual size_t write(char const *src, size_t len, seek_off_t) = 0;
};
#endif /* _INCLUDE__RAM_FS__NODE_H_ */

57
repos/os/include/ram_fs/symlink.h
View File

@ -4,44 +4,51 @@
* \date 2012-04-11
*/
/*
* Copyright (C) 2012-2015 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU General Public License version 2.
*/
#ifndef _INCLUDE__RAM_FS__SYMLINK_H_
#define _INCLUDE__RAM_FS__SYMLINK_H_
/* local includes */
#include <ram_fs/node.h>
namespace File_system {
namespace File_system { class Symlink; }
class Symlink : public Node
{
private:
char _link_to[MAX_PATH_LEN];
size_t _len;
class File_system::Symlink : public Node
{
private:
public:
char _link_to[MAX_PATH_LEN];
size_t _len;
Symlink(char const *name): _len(0) { Node::name(name); }
public:
size_t read(char *dst, size_t len, seek_off_t seek_offset)
{
size_t count = min(len, _len-seek_offset);
Genode::memcpy(dst, _link_to+seek_offset, count);
return count;
}
Symlink(char const *name): _len(0) { Node::name(name); }
size_t write(char const *src, size_t len, seek_off_t seek_offset)
{
/* Ideal symlink operations are atomic. */
if (seek_offset) return 0;
size_t read(char *dst, size_t len, seek_off_t seek_offset)
{
size_t count = min(len, _len-seek_offset);
Genode::memcpy(dst, _link_to+seek_offset, count);
return count;
}
_len = min(len, sizeof(_link_to));
Genode::memcpy(_link_to, src, _len);
return _len;
}
size_t write(char const *src, size_t len, seek_off_t seek_offset)
{
/* Ideal symlink operations are atomic. */
if (seek_offset) return 0;
file_size_t length() const { return _len; }
};
}
_len = min(len, sizeof(_link_to));
Genode::memcpy(_link_to, src, _len);
return _len;
}
file_size_t length() const { return _len; }
};
#endif /* _INCLUDE__RAM_FS__SYMLINK_H_ */