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import streams
when defined(posix):
import posix
import buffer/buffer
import config/config
import io/loader
import io/request
import io/urlfilter
import io/window
import ips/serialize
import ips/serversocket
import types/buffersource
import types/cookie
import utils/twtstr
type
ForkCommand* = enum
FORK_BUFFER, FORK_LOADER, REMOVE_CHILD, LOAD_CONFIG
ForkServer* = ref object
process*: Pid
istream*: Stream
ostream*: Stream
ForkServerContext = object
istream: Stream
ostream: Stream
children: seq[(Pid, Pid)]
proc newFileLoader*(forkserver: ForkServer, defaultHeaders: HeaderList = DefaultHeaders, filter = newURLFilter(), cookiejar: CookieJar = nil): FileLoader =
forkserver.ostream.swrite(FORK_LOADER)
forkserver.ostream.swrite(defaultHeaders)
forkserver.ostream.swrite(filter)
forkserver.ostream.swrite(cookiejar)
forkserver.ostream.flush()
forkserver.istream.sread(result)
proc loadForkServerConfig*(forkserver: ForkServer, config: Config) =
forkserver.ostream.swrite(LOAD_CONFIG)
forkserver.ostream.swrite(config.getForkServerConfig())
forkserver.ostream.flush()
proc removeChild*(forkserver: Forkserver, pid: Pid) =
forkserver.ostream.swrite(REMOVE_CHILD)
forkserver.ostream.swrite(pid)
forkserver.ostream.flush()
proc forkLoader(ctx: var ForkServerContext, defaultHeaders: HeaderList, filter: URLFilter, cookiejar: CookieJar): FileLoader =
var pipefd: array[2, cint]
if pipe(pipefd) == -1:
raise newException(Defect, "Failed to open pipe.")
let pid = fork()
if pid == 0:
# child process
for i in 0 ..< ctx.children.len: ctx.children[i] = (Pid(0), Pid(0))
ctx.children.setLen(0)
zeroMem(addr ctx, sizeof(ctx))
discard close(pipefd[0]) # close read
runFileLoader(pipefd[1], defaultHeaders, filter, cookiejar)
assert false
let readfd = pipefd[0] # get read
discard close(pipefd[1]) # close write
var readf: File
if not open(readf, FileHandle(readfd), fmRead):
raise newException(Defect, "Failed to open output handle.")
assert readf.readChar() == char(0u8)
close(readf)
discard close(pipefd[0])
return FileLoader(process: pid)
proc forkBuffer(ctx: var ForkServerContext): Pid =
var source: BufferSource
var config: BufferConfig
var attrs: WindowAttributes
var mainproc: Pid
ctx.istream.sread(source)
ctx.istream.sread(config)
ctx.istream.sread(attrs)
ctx.istream.sread(mainproc)
let loader = ctx.forkLoader(DefaultHeaders, config.filter, config.cookiejar) #TODO make this configurable
let pid = fork()
if pid == 0:
for i in 0 ..< ctx.children.len: ctx.children[i] = (Pid(0), Pid(0))
ctx.children.setLen(0)
zeroMem(addr ctx, sizeof(ctx))
launchBuffer(config, source, attrs, loader, mainproc)
assert false
ctx.children.add((pid, loader.process))
return pid
proc runForkServer() =
var ctx: ForkServerContext
ctx.istream = newFileStream(stdin)
ctx.ostream = newFileStream(stdout)
while true:
try:
var cmd: ForkCommand
ctx.istream.sread(cmd)
case cmd
of REMOVE_CHILD:
var pid: Pid
ctx.istream.sread(pid)
for i in 0 .. ctx.children.high:
if ctx.children[i][0] == pid:
ctx.children.del(i)
break
of FORK_BUFFER:
ctx.ostream.swrite(ctx.forkBuffer())
of FORK_LOADER:
var defaultHeaders: HeaderList
var filter: URLFilter
var cookiejar: CookieJar
ctx.istream.sread(defaultHeaders)
ctx.istream.sread(filter)
ctx.istream.sread(cookiejar)
let loader = ctx.forkLoader(defaultHeaders, filter, cookiejar)
ctx.ostream.swrite(loader)
ctx.children.add((loader.process, Pid(-1)))
of LOAD_CONFIG:
var config: ForkServerConfig
ctx.istream.sread(config)
width_table = makewidthtable(config.ambiguous_double)
SocketDirectory = config.tmpdir
ctx.ostream.flush()
except IOError:
# EOF
break
ctx.istream.close()
ctx.ostream.close()
# Clean up when the main process crashed.
for childpair in ctx.children:
let a = childpair[0]
let b = childpair[1]
discard kill(cint(a), cint(SIGTERM))
if b != -1:
discard kill(cint(b), cint(SIGTERM))
quit(0)
proc newForkServer*(): ForkServer =
new(result)
var pipefd_in: array[2, cint]
var pipefd_out: array[2, cint]
if pipe(pipefd_in) == -1:
raise newException(Defect, "Failed to open input pipe.")
if pipe(pipefd_out) == -1:
raise newException(Defect, "Failed to open output pipe.")
let pid = fork()
if pid == -1:
raise newException(Defect, "Failed to fork the fork process.")
elif pid == 0:
# child process
let readfd = pipefd_in[0]
discard close(pipefd_in[1]) # close write
let writefd = pipefd_out[1]
discard close(pipefd_out[0]) # close read
discard dup2(readfd, stdin.getFileHandle())
discard dup2(writefd, stdout.getFileHandle())
discard close(pipefd_in[0])
discard close(pipefd_out[1])
runForkServer()
assert false
else:
discard close(pipefd_in[0]) # close read
discard close(pipefd_out[1]) # close write
var readf, writef: File
if not open(writef, pipefd_in[1], fmWrite):
raise newException(Defect, "Failed to open output handle")
if not open(readf, pipefd_out[0], fmRead):
raise newException(Defect, "Failed to open input handle")
result.ostream = newFileStream(writef)
result.istream = newFileStream(readf)
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