1/*  Title:      Pure/PIDE/prover.scala
2    Author:     Makarius
3    Options:    :folding=explicit:
4
5Prover process wrapping.
6*/
7
8package isabelle
9
10
11import java.io.{InputStream, OutputStream, BufferedOutputStream, IOException}
12
13
14object Prover
15{
16  /* messages */
17
18  sealed abstract class Message
19  type Receiver = Message => Unit
20
21  class Input(val name: String, val args: List[String]) extends Message
22  {
23    override def toString: String =
24      XML.Elem(Markup(Markup.PROVER_COMMAND, List((Markup.NAME, name))),
25        args.map(s =>
26          List(XML.Text("\n"), XML.elem(Markup.PROVER_ARG, YXML.parse_body(s)))).flatten).toString
27  }
28
29  class Output(val message: XML.Elem) extends Message
30  {
31    def kind: String = message.markup.name
32    def properties: Properties.T = message.markup.properties
33    def body: XML.Body = message.body
34
35    def is_init = kind == Markup.INIT
36    def is_exit = kind == Markup.EXIT
37    def is_stdout = kind == Markup.STDOUT
38    def is_stderr = kind == Markup.STDERR
39    def is_system = kind == Markup.SYSTEM
40    def is_status = kind == Markup.STATUS
41    def is_report = kind == Markup.REPORT
42    def is_syslog = is_init || is_exit || is_system || is_stderr
43
44    override def toString: String =
45    {
46      val res =
47        if (is_status || is_report) message.body.map(_.toString).mkString
48        else Pretty.string_of(message.body)
49      if (properties.isEmpty)
50        kind.toString + " [[" + res + "]]"
51      else
52        kind.toString + " " +
53          (for ((x, y) <- properties) yield x + "=" + y).mkString("{", ",", "}") + " [[" + res + "]]"
54    }
55  }
56
57  class Protocol_Output(props: Properties.T, val bytes: Bytes)
58    extends Output(XML.Elem(Markup(Markup.PROTOCOL, props), Nil))
59  {
60    lazy val text: String = bytes.text
61  }
62}
63
64
65class Prover(
66  receiver: Prover.Receiver,
67  xml_cache: XML.Cache,
68  channel: System_Channel,
69  process: Bash.Process) extends Protocol
70{
71  /** receiver output **/
72
73  private def system_output(text: String)
74  {
75    receiver(new Prover.Output(XML.Elem(Markup(Markup.SYSTEM, Nil), List(XML.Text(text)))))
76  }
77
78  private def protocol_output(props: Properties.T, bytes: Bytes)
79  {
80    receiver(new Prover.Protocol_Output(props, bytes))
81  }
82
83  private def output(kind: String, props: Properties.T, body: XML.Body)
84  {
85    if (kind == Markup.INIT) channel.accepted()
86
87    val main = XML.Elem(Markup(kind, props), Protocol_Message.clean_reports(body))
88    val reports = Protocol_Message.reports(props, body)
89    for (msg <- main :: reports) receiver(new Prover.Output(xml_cache.elem(msg)))
90  }
91
92  private def exit_message(result: Process_Result)
93  {
94    output(Markup.EXIT, Markup.Process_Result(result),
95      List(XML.Text("Return code: " + result.rc.toString)))
96  }
97
98
99
100  /** process manager **/
101
102  private val process_result: Future[Process_Result] =
103    Future.thread("process_result") {
104      val rc = process.join
105      val timing = process.get_timing
106      Process_Result(rc, timing = timing)
107    }
108
109  private def terminate_process()
110  {
111    try { process.terminate }
112    catch {
113      case exn @ ERROR(_) => system_output("Failed to terminate prover process: " + exn.getMessage)
114    }
115  }
116
117  private val process_manager = Standard_Thread.fork("process_manager")
118  {
119    val (startup_failed, startup_errors) =
120    {
121      var finished: Option[Boolean] = None
122      val result = new StringBuilder(100)
123      while (finished.isEmpty && (process.stderr.ready || !process_result.is_finished)) {
124        while (finished.isEmpty && process.stderr.ready) {
125          try {
126            val c = process.stderr.read
127            if (c == 2) finished = Some(true)
128            else result += c.toChar
129          }
130          catch { case _: IOException => finished = Some(false) }
131        }
132        Thread.sleep(10)
133      }
134      (finished.isEmpty || !finished.get, result.toString.trim)
135    }
136    if (startup_errors != "") system_output(startup_errors)
137
138    if (startup_failed) {
139      terminate_process()
140      process_result.join
141      exit_message(Process_Result(127))
142    }
143    else {
144      val (command_stream, message_stream) = channel.rendezvous()
145
146      command_input_init(command_stream)
147      val stdout = physical_output(false)
148      val stderr = physical_output(true)
149      val message = message_output(message_stream)
150
151      val result = process_result.join
152      system_output("process terminated")
153      command_input_close()
154      for (thread <- List(stdout, stderr, message)) thread.join
155      system_output("process_manager terminated")
156      exit_message(result)
157    }
158    channel.accepted()
159  }
160
161
162  /* management methods */
163
164  def join() { process_manager.join() }
165
166  def terminate()
167  {
168    system_output("Terminating prover process")
169    command_input_close()
170
171    var count = 10
172    while (!process_result.is_finished && count > 0) {
173      Thread.sleep(100)
174      count -= 1
175    }
176    if (!process_result.is_finished) terminate_process()
177  }
178
179
180
181  /** process streams **/
182
183  /* command input */
184
185  private var command_input: Option[Consumer_Thread[List[Bytes]]] = None
186
187  private def command_input_close(): Unit = command_input.foreach(_.shutdown)
188
189  private def command_input_init(raw_stream: OutputStream)
190  {
191    val name = "command_input"
192    val stream = new BufferedOutputStream(raw_stream)
193    command_input =
194      Some(
195        Consumer_Thread.fork(name)(
196          consume =
197            {
198              case chunks =>
199                try {
200                  Bytes(chunks.map(_.length).mkString("", ",", "\n")).write_stream(stream)
201                  chunks.foreach(_.write_stream(stream))
202                  stream.flush
203                  true
204                }
205                catch { case e: IOException => system_output(name + ": " + e.getMessage); false }
206            },
207          finish = { case () => stream.close; system_output(name + " terminated") }
208        )
209      )
210  }
211
212
213  /* physical output */
214
215  private def physical_output(err: Boolean): Thread =
216  {
217    val (name, reader, markup) =
218      if (err) ("standard_error", process.stderr, Markup.STDERR)
219      else ("standard_output", process.stdout, Markup.STDOUT)
220
221    Standard_Thread.fork(name) {
222      try {
223        var result = new StringBuilder(100)
224        var finished = false
225        while (!finished) {
226          //{{{
227          var c = -1
228          var done = false
229          while (!done && (result.length == 0 || reader.ready)) {
230            c = reader.read
231            if (c >= 0) result.append(c.asInstanceOf[Char])
232            else done = true
233          }
234          if (result.length > 0) {
235            output(markup, Nil, List(XML.Text(Symbol.decode(result.toString))))
236            result.length = 0
237          }
238          else {
239            reader.close
240            finished = true
241          }
242          //}}}
243        }
244      }
245      catch { case e: IOException => system_output(name + ": " + e.getMessage) }
246      system_output(name + " terminated")
247    }
248  }
249
250
251  /* message output */
252
253  private def message_output(stream: InputStream): Thread =
254  {
255    class EOF extends Exception
256    class Protocol_Error(msg: String) extends Exception(msg)
257
258    val name = "message_output"
259    Standard_Thread.fork(name) {
260      val default_buffer = new Array[Byte](65536)
261      var c = -1
262
263      def read_int(): Int =
264      //{{{
265      {
266        var n = 0
267        c = stream.read
268        if (c == -1) throw new EOF
269        while (48 <= c && c <= 57) {
270          n = 10 * n + (c - 48)
271          c = stream.read
272        }
273        if (c != 10)
274          throw new Protocol_Error("malformed header: expected integer followed by newline")
275        else n
276      }
277      //}}}
278
279      def read_chunk_bytes(): (Array[Byte], Int) =
280      //{{{
281      {
282        val n = read_int()
283        val buf =
284          if (n <= default_buffer.length) default_buffer
285          else new Array[Byte](n)
286
287        var i = 0
288        var m = 0
289        do {
290          m = stream.read(buf, i, n - i)
291          if (m != -1) i += m
292        }
293        while (m != -1 && n > i)
294
295        if (i != n)
296          throw new Protocol_Error("bad chunk (unexpected EOF after " + i + " of " + n + " bytes)")
297
298        (buf, n)
299      }
300      //}}}
301
302      def read_chunk(): XML.Body =
303      {
304        val (buf, n) = read_chunk_bytes()
305        YXML.parse_body_failsafe(UTF8.decode_chars(Symbol.decode, buf, 0, n))
306      }
307
308      try {
309        do {
310          try {
311            val header = read_chunk()
312            header match {
313              case List(XML.Elem(Markup(name, props), Nil)) =>
314                val kind = name.intern
315                if (kind == Markup.PROTOCOL) {
316                  val (buf, n) = read_chunk_bytes()
317                  protocol_output(props, Bytes(buf, 0, n))
318                }
319                else {
320                  val body = read_chunk()
321                  output(kind, props, body)
322                }
323              case _ =>
324                read_chunk()
325                throw new Protocol_Error("bad header: " + header.toString)
326            }
327          }
328          catch { case _: EOF => }
329        }
330        while (c != -1)
331      }
332      catch {
333        case e: IOException => system_output("Cannot read message:\n" + e.getMessage)
334        case e: Protocol_Error => system_output("Malformed message:\n" + e.getMessage)
335      }
336      stream.close
337
338      system_output(name + " terminated")
339    }
340  }
341
342
343
344  /** protocol commands **/
345
346  def protocol_command_bytes(name: String, args: Bytes*): Unit =
347    command_input match {
348      case Some(thread) => thread.send(Bytes(name) :: args.toList)
349      case None => error("Uninitialized command input thread")
350    }
351
352  def protocol_command(name: String, args: String*)
353  {
354    receiver(new Prover.Input(name, args.toList))
355    protocol_command_bytes(name, args.map(Bytes(_)): _*)
356  }
357}
358