nostalgia/deps/ox/src/ox/fs/filesystem.hpp

826 lines
21 KiB
C++

/*
* Copyright 2015 - 2017 gtalent2@gmail.com
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#pragma once
#include <ox/std/std.hpp>
#include "pathiterator.hpp"
#include "filestore.hpp"
namespace ox {
enum FsType {
OxFS_16 = 1,
OxFS_32 = 2,
OxFS_64 = 3
};
enum FileType {
FileType_NormalFile = 1,
FileType_Directory = 2
};
struct FileStat {
uint64_t inode;
uint64_t size;
uint8_t fileType;
};
template<typename String>
struct DirectoryListing {
String name;
FileStat stat;
DirectoryListing() = default;
DirectoryListing(const char *name) {
this->name = name;
}
};
template<typename String>
bool operator<(const DirectoryListing<String> &a, const DirectoryListing<String> &b) {
return a.name < b.name;
}
template<typename InodeId_t>
struct __attribute__((packed)) DirectoryEntry {
InodeId_t inode;
char *getName() {
return (char*) (this + 1);
}
void setName(const char *name) {
auto data = getName();
auto nameLen = ox_strlen(name);
ox_memcpy(data, name, nameLen);
data[nameLen] = 0;
}
static uint64_t spaceNeeded(const char *fileName) {
return sizeof(DirectoryEntry) + ox_strlen(fileName) + 1;
}
/**
* The size in bytes.
*/
uint64_t size() {
return spaceNeeded(getName());
}
};
template<typename InodeId_t, typename FsSize_t>
struct __attribute__((packed)) Directory {
/**
* Number of bytes after this Directory struct.
*/
FsSize_t size = 0;
FsSize_t children = 0;
DirectoryEntry<InodeId_t> *files() {
return size ? (DirectoryEntry<InodeId_t>*) (this + 1) : nullptr;
}
uint64_t getFileInode(const char *name, uint64_t buffSize);
int getChildrenInodes(InodeId_t *inodes, size_t inodesLen);
int rmFile(const char *name);
int copy(Directory<uint64_t, uint64_t> *dirOut);
template<typename List>
int ls(List *list);
};
template<typename InodeId_t, typename FsSize_t>
uint64_t Directory<InodeId_t, FsSize_t>::getFileInode(const char *name, uint64_t buffSize) {
uint64_t inode = 0;
auto current = files();
if (current) {
for (uint64_t i = 0; ox_strcmp(current->getName(), name) != 0;) {
i += current->size();
if (i < this->size) {
current = (DirectoryEntry<InodeId_t>*) (((uint8_t*) current) + current->size());
} else {
current = nullptr;
break;
}
}
if (current) {
inode = current->inode;
}
}
return inode;
}
template<typename InodeId_t, typename FsSize_t>
int Directory<InodeId_t, FsSize_t>::getChildrenInodes(InodeId_t *inodes, size_t inodesLen) {
if (inodesLen >= this->children) {
auto current = files();
if (current) {
for (uint64_t i = 0; i < this->children; i++) {
inodes[i] = current->inode;
current = (DirectoryEntry<InodeId_t>*) (((uint8_t*) current) + current->size());
}
return 0;
} else {
return 1;
}
} else {
return 2;
}
}
template<typename InodeId_t, typename FsSize_t>
int Directory<InodeId_t, FsSize_t>::rmFile(const char *name) {
int err = 1;
auto current = files();
if (current) {
for (uint64_t i = 0; i < this->size;) {
i += current->size();
if (ox_strcmp(current->getName(), name) == 0) {
auto dest = (uint8_t*) current;
auto src = dest + current->size();
ox_memcpy(dest, src, this->size - i);
this->size -= current->size();
this->children--;
err = 0;
break;
}
current = (DirectoryEntry<InodeId_t>*) (((uint8_t*) current) + current->size());
}
}
return err;
}
template<typename InodeId_t, typename FsSize_t>
int Directory<InodeId_t, FsSize_t>::copy(Directory<uint64_t, uint64_t> *dirOut) {
auto current = files();
auto dirOutBuff = (uint8_t*) dirOut;
dirOutBuff += sizeof(Directory<uint64_t, uint64_t>);
dirOut->size = this->size;
dirOut->children = this->children;
if (current) {
for (uint64_t i = 0; i < this->children; i++) {
auto entry = (DirectoryEntry<uint64_t>*) dirOutBuff;
entry->inode = current->inode;
entry->setName(current->getName());
current = (DirectoryEntry<InodeId_t>*) (((uint8_t*) current) + current->size());
dirOutBuff += entry->size();
}
return 0;
} else {
return 1;
}
}
template<typename InodeId_t, typename FsSize_t>
template<typename List>
int Directory<InodeId_t, FsSize_t>::ls(List *list) {
auto current = files();
if (current) {
for (uint64_t i = 0; i < this->children; i++) {
list->push_back(current->getName());
(*list)[i].stat.inode = current->inode;
current = (DirectoryEntry<InodeId_t>*) (((uint8_t*) current) + current->size());
}
return 0;
} else {
return 1;
}
}
class FileSystem {
public:
virtual ~FileSystem() {};
virtual int stripDirectories() = 0;
virtual int mkdir(const char *path) = 0;
template<typename List>
int ls(const char *path, List *list);
virtual int read(const char *path, void *buffer, size_t buffSize) = 0;
virtual int read(uint64_t inode, void *buffer, size_t size) = 0;
virtual int read(uint64_t inode, size_t readStart, size_t readSize, void *buffer, size_t *size) = 0;
virtual uint8_t *read(uint64_t inode, size_t *size) = 0;
virtual int remove(uint64_t inode, bool recursive = false) = 0;
virtual int remove(const char *path, bool recursive = false) = 0;
virtual void resize(uint64_t size = 0) = 0;
virtual int write(const char *path, void *buffer, uint64_t size, uint8_t fileType = FileType_NormalFile) = 0;
virtual int write(uint64_t inode, void *buffer, uint64_t size, uint8_t fileType = FileType_NormalFile) = 0;
virtual FileStat stat(uint64_t inode) = 0;
virtual FileStat stat(const char *path) = 0;
virtual uint64_t spaceNeeded(uint64_t size) = 0;
virtual uint64_t available() = 0;
virtual uint64_t size() = 0;
virtual uint8_t *buff() = 0;
protected:
virtual int readDirectory(const char *path, Directory<uint64_t, uint64_t> *dirOut) = 0;
};
template<typename List>
int FileSystem::ls(const char *path, List *list) {
auto s = stat(path);
uint8_t dirBuff[s.size * 4];
auto dir = (Directory<uint64_t, uint64_t>*) dirBuff;
auto err = readDirectory(path, dir);
err |= dir->ls(list);
return err;
}
FileSystem *createFileSystem(uint8_t *buff, size_t buffSize, bool ownsBuff = false);
/**
* Creates a larger version of the given FileSystem.
*/
FileSystem *expandCopy(FileSystem *src);
/**
* Calls expandCopy and deletes the original FileSystem and buff a resize was
* performed.
*/
FileSystem *expandCopyCleanup(FileSystem *fs, size_t size);
template<typename FileStore, FsType FS_TYPE>
class FileSystemTemplate: public FileSystem {
private:
FileStore *m_store = nullptr;
bool m_ownsBuff = false;
public:
// static members
static typename FileStore::InodeId_t INODE_RANDOM;
static typename FileStore::InodeId_t INODE_ROOT_DIR;
static typename FileStore::InodeId_t INODE_RESERVED_END;
explicit FileSystemTemplate(uint8_t *buff, bool ownsBuff = false);
~FileSystemTemplate();
int stripDirectories() override;
int mkdir(const char *path) override;
int read(const char *path, void *buffer, size_t buffSize) override;
int read(uint64_t inode, void *buffer, size_t buffSize) override;
int read(uint64_t inode, size_t readStart, size_t readSize, void *buffer, size_t *size) override;
uint8_t *read(uint64_t inode, size_t *size) override;
void resize(uint64_t size = 0) override;
int remove(uint64_t inode, bool recursive = false) override;
int remove(const char *path, bool recursive = false) override;
int write(const char *path, void *buffer, uint64_t size, uint8_t fileType = FileType_NormalFile) override;
int write(uint64_t inode, void *buffer, uint64_t size, uint8_t fileType = FileType_NormalFile) override;
FileStat stat(const char *path) override;
FileStat stat(uint64_t inode) override;
uint64_t findInodeOf(const char *name);
uint64_t spaceNeeded(uint64_t size) override;
uint64_t available() override;
uint64_t size() override;
uint8_t *buff() override;
/**
* Moves an entry from one directory to another.
* @param src the path to the file
* @param dest the path of the destination directory
*/
int move(const char *src, const char *dest);
/**
* Removes an entry from a directory. This does not delete the referred to file.
*/
int rmDirectoryEntry(const char *path);
static uint8_t *format(uint8_t *buffer, typename FileStore::FsSize_t size, bool useDirectories);
protected:
int readDirectory(const char *path, Directory<uint64_t, uint64_t> *dirOut) override;
private:
uint64_t generateInodeId();
int insertDirectoryEntry(const char *dirPath, const char *fileName, uint64_t inode);
void expand(uint64_t size);
};
template<typename FileStore, FsType FS_TYPE>
FileSystemTemplate<FileStore, FS_TYPE>::FileSystemTemplate(uint8_t *buff, bool ownsBuff) {
m_store = (FileStore*) buff;
m_ownsBuff = ownsBuff;
}
template<typename FileStore, FsType FS_TYPE>
FileSystemTemplate<FileStore, FS_TYPE>::~FileSystemTemplate() {
if (m_ownsBuff) {
delete[] (uint8_t*) m_store;
}
}
template<typename FileStore, FsType FS_TYPE>
typename FileStore::InodeId_t FileSystemTemplate<FileStore, FS_TYPE>::INODE_RANDOM = 1;
template<typename FileStore, FsType FS_TYPE>
typename FileStore::InodeId_t FileSystemTemplate<FileStore, FS_TYPE>::INODE_ROOT_DIR = 2;
template<typename FileStore, FsType FS_TYPE>
typename FileStore::InodeId_t FileSystemTemplate<FileStore, FS_TYPE>::INODE_RESERVED_END = 100;
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::stripDirectories() {
return m_store->removeAllType(FileType::FileType_Directory);
}
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::mkdir(const char *path) {
if (!stat(path).inode) {
Directory<typename FileStore::InodeId_t, typename FileStore::FsSize_t> dir;
return write(path, &dir, sizeof(dir), FileType::FileType_Directory);
} else {
return 1;
}
}
template<typename FileStore, FsType FS_TYPE>
FileStat FileSystemTemplate<FileStore, FS_TYPE>::stat(const char *path) {
auto inode = findInodeOf(path);
FileStat stat;
auto s = m_store->stat(inode);
stat.size = s.size;
stat.inode = s.inodeId;
stat.fileType = s.fileType;
return stat;
}
#ifdef _MSC_VER
#pragma warning(disable:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
FileStat FileSystemTemplate<FileStore, FS_TYPE>::stat(uint64_t inode) {
FileStat stat;
auto s = m_store->stat(inode);
stat.size = s.size;
stat.inode = s.inodeId;
stat.fileType = s.fileType;
return stat;
}
#ifdef _MSC_VER
#pragma warning(default:4244)
#endif
#ifdef _MSC_VER
#pragma warning(disable:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::read(const char *path, void *buffer, size_t buffSize) {
int retval = -1;
// find the inode for the given path
auto inode = findInodeOf(path);
// if inode exists, read the data into buffer
if (inode) {
retval = read(inode, buffer, buffSize);
}
return retval;
}
#ifdef _MSC_VER
#pragma warning(default:4244)
#endif
#ifdef _MSC_VER
#pragma warning(disable:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::read(uint64_t inode, void *buffer, size_t buffSize) {
auto stat = m_store->stat(inode);
if (stat.size <= buffSize) {
return m_store->read(inode, buffer, nullptr);
}
return -1;
}
#ifdef _MSC_VER
#pragma warning(default:4244)
#endif
#ifdef _MSC_VER
#pragma warning(disable:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::read(uint64_t inode, size_t readStart,
size_t readSize, void *buffer,
size_t *size) {
if (size) {
auto stat = m_store->stat(inode);
*size = stat.size;
}
return m_store->read(inode, readStart, readSize, buffer, nullptr);
}
#ifdef _MSC_VER
#pragma warning(disable:4244)
#endif
#ifdef _MSC_VER
#pragma warning(disable:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
uint8_t *FileSystemTemplate<FileStore, FS_TYPE>::read(uint64_t inode, size_t *size) {
auto s = m_store->stat(inode);
auto buff = new uint8_t[s.size];
if (size) {
*size = s.size;
}
if (m_store->read(inode, buff, nullptr)) {
delete []buff;
buff = nullptr;
}
return buff;
}
#ifdef _MSC_VER
#pragma warning(default:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::remove(const char *path, bool recursive) {
auto inode = findInodeOf(path);
if (inode) {
return remove(inode, recursive) | rmDirectoryEntry(path);
} else {
return 1;
}
}
#ifdef _MSC_VER
#pragma warning(disable:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::remove(uint64_t inode, bool recursive) {
auto fileType = stat(inode).fileType;
if (fileType != FileType::FileType_Directory) {
return m_store->remove(inode);
} else if (fileType == FileType::FileType_Directory && recursive) {
int err = 0;
auto dirStat = stat(inode);
auto dirBuffLen = dirStat.size;
uint8_t dirBuff[dirBuffLen];
auto dir = (Directory<typename FileStore::InodeId_t, typename FileStore::FsSize_t>*) dirBuff;
err = read(dirStat.inode, dirBuff, dirBuffLen);
if (err) {
return 1;
}
typename FileStore::InodeId_t inodes[dir->children];
dir->getChildrenInodes(inodes, dir->children);
for (auto i : inodes) {
err |= remove(i, true);
}
if (!err) {
err |= m_store->remove(inode);
}
return err;
} else {
return 1;
}
}
#ifdef _MSC_VER
#pragma warning(default:4244)
#endif
#ifdef _MSC_VER
#pragma warning(disable:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::write(const char *path, void *buffer, uint64_t size, uint8_t fileType) {
int err = 0;
size_t pathLen = ox_strlen(path);
char dirPath[pathLen];
char fileName[pathLen];
PathIterator pathReader(path, pathLen);
err |= pathReader.fileName(fileName, pathLen);
err |= pathReader.dirPath(dirPath, pathLen);
if (err) {
return err;
}
uint64_t inode = findInodeOf(path);
// find an inode value for the given path
if (!inode) {
inode = generateInodeId();
err = insertDirectoryEntry(dirPath, fileName, inode);
}
if (!err) {
err = write(inode, buffer, size, fileType);
}
return err;
}
#ifdef _MSC_VER
#pragma warning(default:4244)
#endif
#ifdef _MSC_VER
#pragma warning(disable:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::write(uint64_t inode, void *buffer, uint64_t size, uint8_t fileType) {
if (m_ownsBuff) {
while (m_store->spaceNeeded(size) > m_store->available()) {
expand(this->size() * 2);
}
}
return m_store->write(inode, buffer, size, fileType);
}
#ifdef _MSC_VER
#pragma warning(default:4244)
#endif
#ifdef _MSC_VER
#pragma warning(disable:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
uint64_t FileSystemTemplate<FileStore, FS_TYPE>::findInodeOf(const char *path) {
const auto pathLen = ox_strlen(path);
PathIterator it(path, pathLen);
char fileName[pathLen];
uint64_t inode = INODE_ROOT_DIR;
while (it.hasNext()) {
auto dirStat = stat(inode);
if (dirStat.inode && dirStat.size >= sizeof(Directory<typename FileStore::InodeId_t, typename FileStore::FsSize_t>)) {
uint8_t dirBuffer[dirStat.size];
auto dir = (Directory<typename FileStore::InodeId_t, typename FileStore::FsSize_t>*) dirBuffer;
if (read(inode, dirBuffer, dirStat.size) == 0) {
if (dirStat.fileType == FileType::FileType_Directory && it.next(fileName, pathLen) == 0) {
inode = dir->getFileInode(fileName, dirStat.size);
} else {
inode = 0; // null out inode and break
break;
}
} else {
inode = 0; // null out inode and break
break;
}
} else {
inode = 0; // null out inode and break
break;
}
}
return inode;
}
#ifdef _MSC_VER
#pragma warning(default:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
void FileSystemTemplate<FileStore, FS_TYPE>::resize(uint64_t size) {
return m_store->resize(size);
}
template<typename FileStore, FsType FS_TYPE>
uint64_t FileSystemTemplate<FileStore, FS_TYPE>::spaceNeeded(uint64_t size) {
return m_store->spaceNeeded(size);
}
template<typename FileStore, FsType FS_TYPE>
uint64_t FileSystemTemplate<FileStore, FS_TYPE>::available() {
return m_store->available();
}
template<typename FileStore, FsType FS_TYPE>
uint64_t FileSystemTemplate<FileStore, FS_TYPE>::size() {
return m_store->size();
}
template<typename FileStore, FsType FS_TYPE>
uint8_t *FileSystemTemplate<FileStore, FS_TYPE>::buff() {
return (uint8_t*) m_store;
}
#ifdef _MSC_VER
#pragma warning(disable:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
uint8_t *FileSystemTemplate<FileStore, FS_TYPE>::format(uint8_t *buffer, typename FileStore::FsSize_t size, bool useDirectories) {
buffer = FileStore::format(buffer, size, (uint16_t) FS_TYPE);
if (buffer && useDirectories) {
Directory<typename FileStore::InodeId_t, typename FileStore::FsSize_t> dir;
FileSystemTemplate<FileStore, FS_TYPE> fs((uint8_t*) buffer);
fs.write(INODE_ROOT_DIR, &dir, sizeof(dir), FileType::FileType_Directory);
}
return (uint8_t*) buffer;
}
#ifdef _MSC_VER
#pragma warning(default:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
uint64_t FileSystemTemplate<FileStore, FS_TYPE>::generateInodeId() {
Random rand;
read(INODE_RANDOM, &rand, sizeof(rand));
uint64_t inode = 0;
// find an inode value for the given path
while (!inode) {
inode = rand.gen();
inode >>= 64 - 8 * sizeof(typename FileStore::InodeId_t);
// make sure this does not already exist
if (inode < INODE_RESERVED_END || stat(inode).inode) {
// that result was unusable, try again
inode = 0;
}
}
write(INODE_RANDOM, &rand, sizeof(rand));
return inode;
}
#ifdef _MSC_VER
#pragma warning(disable:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::insertDirectoryEntry(const char *dirPath, const char *fileName, uint64_t inode) {
auto s = stat(dirPath);
if (s.inode) {
auto spaceNeeded = DirectoryEntry<typename FileStore::InodeId_t>::spaceNeeded(fileName);
size_t dirBuffSize = s.size + spaceNeeded;
uint8_t dirBuff[dirBuffSize];
int err = read(s.inode, dirBuff, dirBuffSize);
if (!err) {
auto dir = (Directory<typename FileStore::InodeId_t, typename FileStore::FsSize_t>*) dirBuff;
dir->size += spaceNeeded;
dir->children++;
auto entry = (DirectoryEntry<typename FileStore::InodeId_t>*) &dirBuff[s.size];
entry->inode = inode;
entry->setName(fileName);
return write(s.inode, dirBuff, dirBuffSize, FileType_Directory);
} else {
return 1;
}
} else {
return 2;
}
}
#ifdef _MSC_VER
#pragma warning(default:4244)
#endif
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::move(const char *src, const char *dest) {
auto inode = stat(src).inode;
if (inode && !stat(dest).inode) {
int err = 0;
size_t srcLen = ox_strlen(src);
char srcDirPath[srcLen];
char srcFileName[srcLen];
PathIterator srcPathReader(src, srcLen);
err |= srcPathReader.fileName(srcFileName, srcLen);
err |= srcPathReader.dirPath(srcDirPath, srcLen);
if (err) {
return err;
}
size_t destLen = ox_strlen(dest);
char destDirPath[destLen];
char destFileName[destLen];
PathIterator destPathReader(dest, destLen);
err |= destPathReader.fileName(destFileName, destLen);
err |= destPathReader.dirPath(destDirPath, destLen);
if (err) {
return err;
}
err = rmDirectoryEntry(src);
if (err) {
return err;
}
err = insertDirectoryEntry(destDirPath, destFileName, inode);
if (!err) {
return err;
}
return 0;
} else {
return 1;
}
}
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::rmDirectoryEntry(const char *path) {
int err = 0;
size_t pathLen = ox_strlen(path);
char dirPath[pathLen];
char fileName[pathLen];
PathIterator pathReader(path, pathLen);
err |= pathReader.fileName(fileName, pathLen);
err |= pathReader.dirPath(dirPath, pathLen);
if (err) {
return err;
}
auto dirStat = stat(dirPath);
auto dirBuffLen = dirStat.size;
uint8_t dirBuff[dirBuffLen];
err = read(dirStat.inode, dirBuff, dirBuffLen);
if (err) {
return err;
}
auto dir = (Directory<typename FileStore::InodeId_t, typename FileStore::FsSize_t>*) dirBuff;
err = dir->rmFile(fileName);
if (err) {
return err;
}
err = write(dirStat.inode, dirBuff, dirBuffLen - DirectoryEntry<typename FileStore::InodeId_t>::spaceNeeded(fileName));
return err;
}
template<typename FileStore, FsType FS_TYPE>
int FileSystemTemplate<FileStore, FS_TYPE>::readDirectory(const char *path, Directory<uint64_t, uint64_t> *dirOut) {
int err = 0;
auto inode = findInodeOf(path);
auto dirStat = stat(inode);
auto dirBuffLen = dirStat.size;
uint8_t dirBuff[dirBuffLen];
auto dir = (Directory<typename FileStore::InodeId_t, typename FileStore::FsSize_t>*) dirBuff;
err = read(dirStat.inode, dirBuff, dirBuffLen);
if (!err) {
return dir->copy(dirOut);
} else {
return 1;
}
}
template<typename FileStore, FsType FS_TYPE>
void FileSystemTemplate<FileStore, FS_TYPE>::expand(uint64_t newSize) {
if (newSize > size()) {
auto newBuff = new uint8_t[newSize];
ox_memcpy(newBuff, m_store, m_store->size());
delete[] m_store;
m_store = (FileStore*) newBuff;
resize(newSize);
}
}
typedef FileSystemTemplate<FileStore16, OxFS_16> FileSystem16;
typedef FileSystemTemplate<FileStore32, OxFS_32> FileSystem32;
typedef FileSystemTemplate<FileStore64, OxFS_64> FileSystem64;
}