| Current File : //proc/self/root/kunden/usr/share/lua/5.4/posix/init.lua |
--[[
POSIX library for Lua 5.1, 5.2, 5.3 & 5.4.
Copyright (C) 2013-2020 Gary V. Vaughan
Copyright (C) 2010-2013 Reuben Thomas <rrt@sc3d.org>
Copyright (C) 2008-2010 Natanael Copa <natanael.copa@gmail.com>
]]
--[[--
Lua POSIX bindings.
In addition to the convenience functions documented in this module, many
APIs from submodules are copied into the return table for backwards
compatibility and, if necessary, wrapped to match the deprecated API.
This means that your old code will continue to work, but that you can
use the improved documented APIs in new code.
@module posix
]]
local _ENV = require 'posix._strict' {
GLOB_MARK = require 'posix.glob'.GLOB_MARK,
O_NOCTTY = require 'posix.fcntl'.O_NOCTTY,
O_RDWR = require 'posix.fcntl'.O_RDWR,
STDIN_FILENO = require 'posix.unistd'.STDIN_FILENO,
STDOUT_FILENO = require 'posix.unistd'.STDOUT_FILENO,
_exit = require 'posix.unistd'._exit,
access = require 'posix.unistd'.access,
argscheck = require 'posix._base'.argscheck,
assert = assert,
bor = require 'posix._base'.bor,
close = require 'posix.unistd'.close,
dup2 = require 'posix.unistd'.dup2,
errno = require 'posix.errno'.errno,
error = error,
execp = require 'posix.unistd'.execp,
exit = os.exit,
fork = require 'posix.unistd'.fork,
getegid = require 'posix.unistd'.getegid,
geteuid = require 'posix.unistd'.geteuid,
getgid = require 'posix.unistd'.getgid,
getuid= require 'posix.unistd'.getuid,
glob = require 'posix.glob'.glob,
grantpt = require 'posix.stdlib'.grantpt,
gsub = string.gsub,
insert = table.insert,
match = string.match,
next = next,
open = require 'posix.fcntl'.open,
openpt = require 'posix.stdlib'.openpt,
pcall = pcall,
pipe = require 'posix.unistd'.pipe,
ptsname = require 'posix.stdlib'.ptsname,
rawset = rawset,
remove = table.remove,
require = require,
set_errno = require 'posix.errno'.set_errno,
setmetatable = setmetatable,
stat = require 'posix.sys.stat'.stat,
sub = string.sub,
tonumber = tonumber,
type = type,
unlockpt = require 'posix.stdlib'.unlockpt,
wait = require 'posix.sys.wait'.wait,
}
-- FIXME: specl-14.x breaks function environments here :(
local GLOB_MARK, STDIN_FILENO, STDOUT_FILENO, _exit, close, errno, execp, exit, fork, glob, pipe, wait =
GLOB_MARK, STDIN_FILENO, STDOUT_FILENO, _exit, close, errno, execp, exit, fork, glob, pipe, wait
local function Peuidaccess(file, mode)
local euid, egid = geteuid(), getegid()
if getuid() == euid and getgid() == egid then
-- If we are not set-uid or set-gid, access does the same.
return access(file, mode)
end
local stats = stat(file)
if not stats then
return
end
-- The super-user can read and write any file, and execute any file
-- that anyone can execute.
if euid == 0 and ((not match(mode, 'x')) or match(stats.st_mode, 'x')) then
return 0
end
-- Convert to simple list of modes.
mode = gsub(mode, '[^rwx]', '')
if mode == '' then
return 0 -- The file exists.
end
-- Get the modes we need.
local granted = sub(stats.st_mode, 1, 3)
if euid == stats.st_uid then
granted = sub(stats.st_mode, 7, 9)
elseif egid == stats.st_gid or set.new(posix.getgroups()):member(stats.st_gid) then
granted = sub(stats.st_mode, 4, 6)
end
granted = gsub(granted, '[^rwx]', '')
if gsub('[^' .. granted .. ']', mode) == '' then
return 0
end
set_errno(EACCESS)
end
local function Pexecx(task, ...)
if type(task) == 'table' then
local path = remove(task, 1)
execp(path, task)
-- Only get here if there's an error; kill the fork
local _, n = errno()
_exit(n)
else
-- Function call must flush open file descriptors et.al. with `os.exit()`
exit(task(...) or 0)
end
end
local function Pglob(args)
-- Support previous `glob '.*'` style calls.
if type(args) == 'string' then
args = {pattern=args}
elseif type(args) ~= 'table' then
args = {}
end
local flags = 0
if args.MARK then
flags = GLOB_MARK
end
return glob(args.pattern, flags)
end
local function Popenpty(term, win)
local ok, errmsg, master, slave, slave_name
master, errmsg = openpt(bor(O_RDWR, O_NOCTTY))
if master then
ok, errmsg = grantpt(master)
if ok then
ok, errmsg = unlockpt(master)
if ok then
slave_name, errmsg = ptsname(master)
if slave_name then
slave, errmsg = open(slave_name, bor(O_RDWR, O_NOCTTY))
if slave then
return master, slave, slave_name
end
end
end
end
close(master)
end
return nil, errmsg
end
local function Ppclose(pfd)
close(pfd.fd)
for i = 1, #pfd.pids - 1 do
wait(pfd.pids[i])
end
local _, reason, status = wait(pfd.pids[#pfd.pids])
return reason, status
end
local function move_fd(from_fd, to_fd)
if from_fd ~= to_fd then
if not dup2(from_fd, to_fd) then
error 'error dup2-ing'
end
close(from_fd)
end
end
local function Ppopen(task, mode, pipe_fn)
local read_fd, write_fd = (pipe_fn or pipe)()
if not read_fd then
error 'error opening pipe'
end
local parent_fd, child_fd, in_fd, out_fd
if mode == 'r' then
parent_fd, child_fd, in_fd, out_fd = read_fd, write_fd, STDIN_FILENO, STDOUT_FILENO
elseif mode == 'w' then
parent_fd, child_fd, in_fd, out_fd = write_fd, read_fd, STDOUT_FILENO, STDIN_FILENO
else
error 'invalid mode'
end
local pid = fork()
if pid == nil then
error 'error forking'
elseif pid == 0 then -- child process
move_fd(child_fd, out_fd)
close(parent_fd)
_exit(Pexecx(task, child_fd, in_fd, out_fd))
end -- parent process
close(child_fd)
return {pids={pid}, fd=parent_fd}
end
local function Ppopen_pipeline(tasks, mode, pipe_fn)
local first, from, to, inc = 1, 2, #tasks, 1
if mode == 'w' then
first, from, to, inc = #tasks, #tasks - 1, 1, -1
end
local pfd = Ppopen(tasks[first], mode, pipe_fn)
for i = from, to, inc do
local pfd_next = Ppopen(function(fd, in_fd, out_fd)
move_fd(pfd.fd, in_fd)
_exit(Pexecx(tasks[i]))
end,
mode,
pipe_fn)
close(pfd.fd)
pfd.fd = pfd_next.fd
insert(pfd.pids, pfd_next.pids[1])
end
return pfd
end
local function Pspawn(task, ...)
local pid, err = fork()
if pid == nil then
return pid, err
elseif pid == 0 then
Pexecx(task, ...)
else
local _, reason, status = wait(pid)
return status, reason -- If wait failed, status is nil & reason is error
end
end
local function Ptimeradd(x, y)
local sec, usec = 0, 0
if x.tv_sec or x.tv_usec then
sec = sec + (tonumber(x.tv_sec) or 0)
usec = usec + (tonumber(x.tv_usec) or 0)
else
sec = sec + (tonumber(x.sec) or 0)
usec = usec + (tonumber(x.usec) or 0)
end
if y.tv_sec or y.tv_usec then
sec = sec + (tonumber(y.tv_sec) or 0)
usec = usec + (tonumber(y.tv_usec) or 0)
else
sec = sec + (tonumber(y.sec) or 0)
usec = usec + (tonumber(y.usec) or 0)
end
while usec > 1000000 do
sec = sec + 1
usec = usec - 1000000
end
return {sec=sec, usec=usec}
end
local function Ptimercmp(x, y)
local x = {sec=x.tv_sec or x.sec or 0, usec=x.tv_usec or x.usec or 0}
local y = {sec=y.tv_sec or y.sec or 0, usec=y.tv_usec or y.usec or 0}
if x.sec ~= y.sec then
return x.sec - y.sec
else
return x.usec - y.usec
end
end
local function Ptimersub(x,y)
local sec, usec = 0, 0
if x.tv_sec or x.tv_usec then
sec = (tonumber(x.tv_sec) or 0)
usec = (tonumber(x.tv_usec) or 0)
else
sec = (tonumber(x.sec) or 0)
usec = (tonumber(x.usec) or 0)
end
if y.tv_sec or y.tv_usec then
sec = sec - (tonumber(y.tv_sec) or 0)
usec = usec - (tonumber(y.tv_usec) or 0)
else
sec = sec - (tonumber(y.sec) or 0)
usec = usec - (tonumber(y.usec) or 0)
end
while usec < 0 do
sec = sec - 1
usec = usec + 1000000
end
return { sec = sec, usec = usec }
end
-- For backwards compatibility, copy all table entries into M namespace.
local M = {}
do
local names = {
'ctype', 'dirent', 'errno', 'fcntl', 'fnmatch', 'glob', 'grp',
'libgen', 'poll', 'pwd', 'sched', 'signal', 'stdio', 'stdlib', 'sys.msg',
'sys.resource', 'sys.socket', 'sys.stat', 'sys.statvfs', 'sys.time',
'sys.times', 'sys.utsname', 'sys.wait', 'syslog', 'termio', 'time',
'unistd', 'utime'
}
for i = 1, #names do
local name = names[i]
local t = require('posix.' .. name)
for k, v in next, t do
if k ~= 'version' then
assert(M[k] == nil, 'posix namespace clash: ' .. name .. '.' .. k)
M[k] = v
end
end
end
-- Inject deprecated APIs (overwriting submodules) for backwards compatibility.
for k, v in next, (require 'posix.deprecated') do
M[k] = v
end
for k, v in next, (require 'posix.compat') do
M[k] = v
end
end
local function merge(t, r)
for k, v in next, t do
r[k] = r[k] or v
end
return r
end
return setmetatable(merge(M, {
--- Close a pipeline opened with popen or popen_pipeline.
-- @function pclose
-- @tparam table pfd pipeline object
-- @return values as for @{posix.sys.wait.wait}, for the last (or only)
-- stage of the pipeline
pclose = argscheck('pclose(table)', Ppclose),
--- Check permissions like @{posix.unistd.access}, but for euid.
-- Based on the glibc function of the same name. Does not always check
-- for read-only file system, text busy, etc., and does not work with
-- ACLs &c.
-- @function euidaccess
-- @string file file to check
-- @string mode checks to perform (as for access)
-- @return 0 if access allowed; <code>nil</code> otherwise (and errno is set)
euidaccess = argscheck('euidaccess(string, string)', Peuidaccess),
--- Exec a command or Lua function.
-- @function execx
-- @tparam table task argument list for @{posix.unistd.execp} or a Lua
-- function, which should read from standard input, write to standard
-- output, and return an exit code
-- @param ... positional arguments to the function
-- @treturn nil on error(normally does not return)
-- @treturn string error message
execx = argscheck('execx(function|table, ?any...)', Pexecx),
--- Find all files in this directory matching a shell pattern.
-- The flag MARK appends a trailing slash to matches that are directories.
-- @function glob
-- @tparam table|string|nil args the three possible parameters can be used to
-- override the default values for `pattern` and `MARK`, which are `"*"` and
-- `false` respectively. A table will be checked for optional keys `pattern`
-- and `MARK`. A string will be used as the glob pattern.
-- @treturn table matching files and directories
glob = argscheck('glob(?string|table)', Pglob),
--- Open a pseudo-terminal.
-- Based on the glibc function of the same name.
-- @function openpty
-- @fixme add support for term and win arguments
-- @treturn[1] int master file descriptor
-- @treturn[1] int slave file descriptor
-- @treturn[1] string slave file name
-- @return[2] nil
-- @treturn[2] string error message
openpty = argscheck('openpty()', Popenpty),
--- Run a commands or Lua function in a sub-process.
-- @function popen
-- @tparam table task argument list for @{posix.unistd.execp} or a Lua
-- function, which should read from standard input, write to standard
-- output, and return an exit code
-- @tparam string mode `"r"` for read or `"w"` for write
-- @func[opt] pipe_fn function returning a paired read and
-- write file descriptor (*default* @{posix.unistd.pipe})
-- @treturn pfd pipeline object
-- @see posix.execx
-- @see posix.spawn
popen = argscheck('popen(function|table, string, ?function)', Ppopen),
--- Perform a series of commands and Lua functions as a pipeline.
-- @function popen_pipeline
-- @tparam table t tasks for @{posix.execx}
-- @tparam string mode `"r"` for read or `"w"` for write
-- @func[opt] pipe_fn function returning a paired read and
-- write file descriptor (*default* @{posix.unistd.pipe})
-- @treturn pfd pipeline object
popen_pipeline = argscheck('popen_pipeline(function|table, string, ?function)',
Ppopen_pipeline),
--- Run a command or function in a sub-process using @{posix.execx}.
-- @function spawn
-- @tparam table task argument list for @{posix.unistd.execp} or a Lua
-- function, which should read from standard input, write to standard
-- output, and return an exit code
-- @param ... as for @{posix.execx}
-- @return values as for @{posix.sys.wait.wait}
spawn = argscheck('spawn(function|table, ?any...)', Pspawn),
--- Add one gettimeofday() returned timeval to another.
-- @function timeradd
-- @param x a timeval
-- @param y another timeval
-- @return x + y, adjusted for usec overflow
timeradd = argscheck('timeradd(table, table)', Ptimeradd),
--- Compare one gettimeofday() returned timeval with another
-- @function timercmp
-- @param x a timeval
-- @param y another timeval
-- @return 0 if x and y are equal, >0 if x is newer, <0 if y is newer
timercmp = argscheck('timercmp(table, table)', Ptimercmp),
--- Subtract one gettimeofday() returned timeval from another.
-- @function timersub
-- @param x a timeval
-- @param y another timeval
-- @return x - y, adjusted for usec underflow
timersub = argscheck('timersub(table, table)', Ptimersub),
}), {
--- Metamethods
-- @section metamethods
--- Lazy loading of luaposix modules.
-- Don't load everything on initial startup, wait until first attempt
-- to access a submodule, and then load it on demand.
-- @function __index
-- @string name submodule name
-- @treturn table|nil the submodule that was loaded to satisfy the missing
-- `name`, otherise `nil` if nothing was found
-- @usage
-- local version = require 'posix'.version
__index = function(self, name)
local ok, t = pcall(require, 'posix.' ..name)
if ok then
rawset(self, name, t)
return t
end
end,
})