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HyperionOS/Src/Hyperion-kernel/lib/modules/Hyperion/10_vfs.kmod

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-- :Minify:--
local kernel = ...
local vfs = {}
kernel.vfs = vfs
vfs.mounts = {["$"] = "/"}
vfs.disks = kernel.disks
-- Path normalization
local function normalizePath(path)
local task = kernel.currentTask
local cwd = task.cwd or "/"
if path:sub(1, 1) ~= "/" then path = cwd .. "/" .. path end
local parts = {}
for part in path:gmatch("[^/]+") do
if part == ".." then
if #parts > 0 then table.remove(parts) end
elseif part ~= "." and part ~= "" then
table.insert(parts, part)
end
end
return "/" .. table.concat(parts, "/")
end
function vfs.splitPath(path)
local rv=string.split(path,"/")
while table.indexOf(rv, "") ~= -1 do
table.remove(rv, table.indexOf(rv, ""))
end
return rv
end
-- Resolve mount and disk path
local function resolvePath(path)
path = normalizePath(path)
local mountPoint = nil
local mountId = nil
for id, mp in pairs(vfs.mounts) do
if path == mp or (mp == "/" and path:sub(1, 1) == "/") or path:sub(1, #mp + 1) == mp .. "/" then
if not mountPoint or #mp > #mountPoint then
mountPoint = mp
mountId = id
end
end
end
if not mountId then
error("ENODEV")
end
local diskPath = path:sub(#mountPoint + 1)
if diskPath == "" then
diskPath = "/"
end
if kernel.config.logPathResolution then
kernel.log("Path '"..path.."' resolved to disk '"..mountId.."' and path '"..diskPath.."'")
end
return vfs.disks[mountId], diskPath
end
-- Allocate file descriptor for current task
local function allocFD(task)
local fd = 0
while task.fd[fd] do fd = fd + 1 end
if fd >= kernel.config.maxFilesPerTask then error("ENFILE") end
return fd
end
-- System-wide open file limit
local total = 0
local function checkSystemLimit()
if total >= kernel.config.maxOpenFiles - 16 then error("ENFILE") end
end
-- File object constructor
local function newFileObj(handle, mode, path, meta, type)
return {
handle = handle,
mode = mode,
path = path,
meta = meta,
type = type,
refcount = 1
}
end
function vfs.newfd(fdobj)
checkSystemLimit()
total=total+1
local fd = allocFD(kernel.currentTask)
kernel.currentTask.fd[fd]=fdobj
end
-- Parse metafile
local function parseMetafile(file)
if not file or file == "" then return {} end
local ret = {}
local pointer = 1
while pointer <= #file do
local namelen = file:byte(pointer)
pointer = pointer + 1
local name = file:sub(pointer, pointer + namelen - 1)
pointer = pointer + namelen
local owner = file:byte(pointer)
local group = file:byte(pointer + 1)
local perms = file:byte(pointer + 2)
pointer = pointer + 3
local cmetalen = file:byte(pointer)
pointer = pointer + 1
local cmeta = ""
if cmetalen > 0 then
cmeta = file:sub(pointer, pointer + cmetalen - 1)
pointer = pointer + cmetalen
end
ret[name] = {owner = owner, group = group, perms = perms, cmeta = cmeta}
end
return ret
end
-- Build metafile
local function makeMetafile(meta)
local file = ""
for name, m in pairs(meta) do
local entry = ""
entry = entry .. string.char(#name) .. name
entry = entry .. string.char(m.owner, m.group, m.perms)
entry = entry .. string.char(#m.cmeta) .. m.cmeta
file = file .. entry
end
return file
end
-- Get file metadata object
local function getFileMeta(path)
local disk, fullPath = resolvePath(path)
fullPath = normalizePath(fullPath)
local parts = {}
for p in fullPath:gmatch("[^/]+") do table.insert(parts, p) end
-- default fallback
local default = {owner = 0, group = 0, perms = 63, cmeta = ""}
-- walk from deepest parent upward
for i = #parts, 1, -1 do
local parent = "/" .. table.concat(parts, "/", 1, i - 1)
if parent ~= "/" then parent = parent .. "/" end
local target = parts[i]
if target == ".meta" then error("Cannot open metafile") end
local metaPath = parent .. ".meta"
if disk:fileExists(metaPath) then
local f = disk:open(metaPath, "r")
local text = f.read(65535)
f.close()
local parsed = parseMetafile(text)
if parsed[target] then return parsed[target] end
end
end
return default
end
local function ensureParentMeta(path)
local disk, fullPath = resolvePath(path)
fullPath = normalizePath(fullPath)
-- split parent + name
local parent, name = fullPath:match("^(.*)/([^/]+)$")
if not parent then
parent = "/"
name = fullPath:gsub("^/", "")
end
if name == ".meta" then error("Cannot open metafile") end
if parent ~= "/" and parent:sub(-1) ~= "/" then parent = parent .. "/" end
local metaPath = parent .. ".meta"
if not disk:fileExists(metaPath) then
local f = disk:open(metaPath, "w")
f.write("")
f.close()
end
return metaPath, name
end
-- Permission checking
local function checkperms(meta, mode)
local modes = {
r = {owner = 5, group = 3, everyone = 1},
w = {owner = 4, group = 2, everyone = 0},
a = {owner = 4, group = 2, everyone = 0}
}
local bits = meta.perms
local function bit_is_set(num, bit)
return math.floor(num / (2 ^ bit)) % 2 == 1
end
if kernel.uid == 0 then return true end
if kernel.uid == meta.owner and bit_is_set(bits, modes[mode].owner) then
return true
end
if meta.group and kernel.groups then
for _, gid in ipairs(kernel.groups) do
if gid == meta.group and bit_is_set(bits, modes[mode].group) then
return true
end
end
end
if bit_is_set(bits, modes[mode].everyone) then return true end
error("EACCES")
end
-- mounts
local function normalizeMountPoint(path)
path = normalizePath(path)
if path ~= "/" and path:sub(-1) == "/" then path = path:sub(1, -2) end
return path
end
local required = {
"open",
"type",
"list",
"attributes",
"fileExists",
"makeDirectory",
"remove"
}
local function check(disk)
for _, name in ipairs(required) do
if type(disk[name]) ~= "function" then
error("Invalid disk: missing method '" .. name .. "'")
end
end
end
function vfs.mount(target, diskOrId)
if kernel.uid ~= 0 then error("EPERM") end
if not target then error("EINVAL") end
target = normalizeMountPoint(target)
if not vfs.exists(target) then vfs.mkdir(target) end
if vfs.type(target) ~= "directory" then error("EINVAL") end
local disk
local id
if type(diskOrId) == "string" then
disk = kernel.disks[diskOrId]
if not disk then error("ENODEV") end
check(disk)
id = diskOrId
elseif type(diskOrId) == "table" then
check(disk)
disk = diskOrId
id = disk.address
vfs.disks[id] = disk
else
error("EINVAL")
end
-- Prevent shadowing an existing mount
for _, mp in pairs(vfs.mounts) do if mp == target then error("EBUSY") end end
vfs.mounts[id] = target
return true
end
function vfs.umount(target)
if kernel.uid ~= 0 then error("EPERM") end
if not target then error("EINVAL") end
target = normalizeMountPoint(target)
for id, mp in pairs(vfs.mounts) do
if mp == target then
if id == "$" then error("EBUSY") end -- root fs
vfs.mounts[id] = nil
return true
end
end
error("EINVAL")
end
-- Open file
function vfs.open(path, mode)
checkSystemLimit()
local task = kernel.currentTask
local fd = allocFD(task)
local disk, diskPath = resolvePath(path)
if not disk then error("NODISK") end
local meta = getFileMeta(path)
checkperms(meta, mode)
local handle
if disk:type(diskPath)~="directory" then
handle = disk:open(diskPath, mode)
if type(handle)~="table" then error("ENFILE") end
end
task.fd[fd] = newFileObj(handle, mode, path, meta, disk:type(diskPath))
if not disk.isvirt then
total = total + 1
end
return fd
end
-- Read
function vfs.read(fd, count)
local task = kernel.currentTask
local file = task.fd[fd]
if not file then error("EBADF") end
if not file.handle.read then error("EBADF") end
return file.handle.read(count or 1)
end
-- Write
function vfs.write(fd, content)
local task = kernel.currentTask
local file = task.fd[fd]
if not file then error("EBADF") end
if not file.handle.write then error("EBADF") end
return file.handle.write(content)
end
-- Pread / Pwrite
function vfs.pread(fd, count, offset)
local task = kernel.currentTask
local file = task.fd[fd]
if not file then error("EBADF") end
if not file.handle.read then error("EBADF") end
if not file.handle.seek then error("EBADF") end
file.handle.seek("set", offset)
return file.handle.read(count or 1)
end
function vfs.pwrite(fd, content, offset)
local task = kernel.currentTask
local file = task.fd[fd]
if not file then error("EBADF") end
if not file.handle.write then error("EBADF") end
if not file.handle.seek then error("EBADF") end
file.handle.seek("set", offset)
return file.handle.write(content)
end
-- Seek
function vfs.lseek(fd, offset, whence)
local task = kernel.currentTask
local file = task.fd[fd]
if not file then error("EBADF") end
if not file.handle.seek then error("EBADF") end
return file.handle.seek(whence or "set", offset)
end
-- Fsync
function vfs.fsync(fd)
local task = kernel.currentTask
local file = task.fd[fd]
if not file then error("EBADF") end
if not file.handle.flush then error("EBADF") end
if file.mode ~= "w" and file.mode ~= "a" then error("EBADF") end
file.handle.flush()
end
-- Close
function vfs.close(fd)
local task = kernel.currentTask
local file = task.fd[fd]
if not file then error("EBADF") end
task.fd[fd] = nil
total = total - 1
file.refcount = file.refcount - 1
if file.refcount <= 0 then
if file.handle.close then
file.handle.close()
end
end
end
-- Sendfile
function vfs.sendfile(outfd, infd, count)
local task = kernel.currentTask
local inFile = task.fd[infd]
local outFile = task.fd[outfd]
if not inFile or not outFile then error("EBADF") end
if not inFile.handle.read then error("EBADF") end
if not outFile.handle.write then error("EBADF") end
local data = inFile.handle.read(count or 1024)
if not data or data == "" then return end
return outFile.handle.write(data)
end
-- Stat / Fstat
function vfs.stat(path)
local disk, diskPath = resolvePath(path)
local meta = getFileMeta(path)
local attrs = disk:attributes(diskPath)
return {
size = attrs.size,
modified = attrs.modified,
created = attrs.created,
owner = meta.owner,
group = meta.group,
xattr = meta.cmeta
}
end
function vfs.fstat(fd)
local task = kernel.currentTask
local file = task.fd[fd]
if not file then error("EBADF") end
local disk, path = resolvePath(file.path)
local attrs = disk:attributes(path)
return {
size = attrs.size,
modified = attrs.modified,
created = attrs.created,
owner = file.meta.owner,
group = file.meta.group,
xattr = file.meta.cmeta
}
end
-- Directory operations
function vfs.listdir(path)
local disk, diskPath = resolvePath(path)
if disk:type(diskPath) ~= "directory" then error("ENOENT") end
local meta = getFileMeta(path)
checkperms(meta, "r")
local list = disk:list(diskPath)
if table.indexOf(list, ".meta") ~= -1 then
table.remove(list, table.indexOf(list, ".meta"))
end
return list
end
function vfs.mkdir(path)
local disk, diskPath = resolvePath(path)
local meta = getFileMeta(path)
checkperms(meta, "w")
disk:makeDirectory(diskPath)
end
function vfs.remove(path)
local disk, diskPath = resolvePath(path)
local meta = getFileMeta(path)
checkperms(meta, "w")
disk:remove(diskPath)
end
-- Permission functions
function vfs.chmod(path, perms)
local disk, diskPath = resolvePath(path)
local meta = getFileMeta(path)
if meta.owner ~= kernel.currentTask.uid then error("EACCES") end
meta.perms = perms
local mpath, target = ensureParentMeta(path)
local mf = disk:open(mpath, "r")
local text = mf.read(65535)
mf.close()
local parsed = parseMetafile(text)
parsed[target] = meta
local f = disk:open(mpath, "w")
f.write(makeMetafile(parsed))
f.close()
end
function vfs.fchmod(fd, perms)
local task = kernel.currentTask
local file = task.fd[fd]
if not file then error("EBADF") end
vfs.chmod(file.path, perms)
end
function vfs.chown(path, uid, gid)
local disk, diskPath = resolvePath(path)
local meta = getFileMeta(path)
if meta.owner ~= kernel.currentTask.uid then error("EACCES") end
meta.owner = uid
meta.group = gid
local mpath, target = ensureParentMeta(path)
local mf = disk:open(mpath, "r")
local text = mf.read(65535)
mf.close()
local parsed = parseMetafile(text)
parsed[target] = meta
local f = disk:open(mpath, "w")
f.write(makeMetafile(parsed))
f.close()
end
function vfs.fchown(fd, uid, gid)
local task = kernel.currentTask
local file = task.fd[fd]
if not file then error("EBADF") end
vfs.chown(file.path, uid, gid)
end
function vfs.exists(path)
local disk, diskPath = resolvePath(path)
local meta = getFileMeta(path)
checkperms(meta, "r")
return disk:fileExists(diskPath)
end
function vfs.type(path)
local disk, diskPath = resolvePath(path)
local meta = getFileMeta(path)
checkperms(meta, "r")
return disk:type(diskPath)
end
function vfs.getcwd() return kernel.currentTask.cwd end
function vfs.chdir(path) kernel.currentTask.cwd = path end
function vfs.dup(oldfd)
local task = kernel.currentTask
local file = task.fd[oldfd]
if not file then error("EBADF") end
checkSystemLimit()
local newfd = allocFD(task)
file.refcount = file.refcount + 1
task.fd[newfd] = file
total = total + 1
return newfd
end
function vfs.dup2(oldfd, newfd)
local task = kernel.currentTask
local file = task.fd[oldfd]
if not file then error("EBADF") end
if newfd < 0 or newfd >= kernel.config.maxFilesPerTask then
error("EBADF")
end
if oldfd == newfd then
return newfd
end
if task.fd[newfd] then
vfs.close(newfd)
end
checkSystemLimit()
file.refcount = file.refcount + 1
task.fd[newfd] = file
total = total + 1
return newfd
end
function vfs.devctl(fd, method, ...)
if not kernel.currentTask.fd[fd] then error("EBADF") end
if not kernel.currentTask.fd[fd].handle[method] then error("EINVAL") end
return kernel.currentTask.fd[fd].handle[method](...)
end
-- Export syscalls
local sys = kernel.syscalls
sys["open"] = vfs.open
sys["close"] = vfs.close
sys["read"] = vfs.read
sys["write"] = vfs.write
sys["pread"] = vfs.pread
sys["pwrite"] = vfs.pwrite
sys["lseek"] = vfs.lseek
sys["fsync"] = vfs.fsync
sys["sendfile"] = vfs.sendfile
sys["stat"] = vfs.stat
sys["fstat"] = vfs.fstat
sys["mkdir"] = vfs.mkdir
sys["remove"] = vfs.remove
sys["listdir"] = vfs.listdir
sys["chmod"] = vfs.chmod
sys["fchmod"] = vfs.fchmod
sys["chown"] = vfs.chown
sys["fchown"] = vfs.fchown
sys["exists"] = vfs.exists
sys["type"] = vfs.type
sys["mount"] = vfs.mount
sys["umount"] = vfs.umount
sys["getcwd"] = vfs.getcwd
sys["chdir"] = vfs.chdir
sys["dup"] = vfs.dup
sys["dup2"] = vfs.dup2
sys["devctl"] = vfs.devctl
kernel.log("VFS module loaded")