Remove the timeout code

It had fundamental problems which seem unlikely to be resolved.
See also issues #664, #695, #765.

.appveyor.yml

@@ -35,7 +35,6 @@ build_script:
   - bash -lc "cd $APPVEYOR_BUILD_FOLDER && ./etc/ci-prepare.sh"
 
 test_script:
-  - bash -lc "rm $APPVEYOR_BUILD_FOLDER/tst/testinstall/timeout.tst" # HACK
   - bash -lc "cd $APPVEYOR_BUILD_FOLDER && ./etc/ci.sh"
 
 on_success:

Makefile.rules

@@ -90,7 +90,6 @@ SOURCES += src/streams.c
 SOURCES += src/stringobj.c
 SOURCES += src/sysfiles.c
 SOURCES += src/system.c
-SOURCES += src/systimers.c
 SOURCES += src/tietze.c
 SOURCES += src/trans.c
 SOURCES += src/vars.c

configure.ac

@@ -535,10 +535,7 @@ AC_SEARCH_LIBS([dlopen], [dl],
 dnl check for timing functions
 AC_CHECK_HEADERS([sys/time.h])
 AC_CHECK_FUNCS([getrusage gettimeofday clock_gettime clock_getres])
-AC_CHECK_FUNCS([setitimer getitimer])
-AC_CHECK_LIB([rt], [timer_create])
-AC_CHECK_FUNCS([timer_settime timer_gettime timer_create])
-AC_CHECK_FUNCS([sys_timer_settime sys_timer_gettime sys_timer_create])
+AC_CHECK_FUNCS([setitimer])
 
 dnl check for functions dealing with virtual memory
 AC_CHECK_FUNCS([vm_allocate sbrk madvise sysconf])

doc/ref/function.xml

@@ -43,17 +43,6 @@ several arguments</Heading>
 
 </Section>
 
-<!-- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -->
-<Section Label="Calling a function with a time limit">
-<Heading>Calling a function with a time limit</Heading>
-
-
-<#Include Label="CallWithTimeout">
-<#Include Label="GAPInfo.TimeoutsSupported">
-</Section>
-
-
-
 
 <!-- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -->
 <Section Label="Functions that do nothing">

doc/ref/makedocreldata.g

@@ -65,7 +65,6 @@ GAPInfo.ManualDataRef:= rec(
     "../../lib/fpmon.gd",
     "../../lib/fpsemi.gd",
     "../../lib/function.g",
-    "../../lib/function.gd",
     "../../lib/galois.gd",
     "../../lib/gasman.gd",
     "../../lib/ghom.gd",

hpcgap/lib/error.g

@@ -111,10 +111,9 @@ Unbind(ErrorInner);
 BIND_GLOBAL("ErrorInner",
         function( arg )
     local   context, mayReturnVoid,  mayReturnObj,  lateMessage,  earlyMessage,  
-            x,  prompt,  res, errorLVars, justQuit, printThisStatement, timeout,
+            x,  prompt,  res, errorLVars, justQuit, printThisStatement,
             location;
 
-    timeout := STOP_TIMEOUT();
 	context := arg[1].context;
     if not IsLVarsBag(context) then
         PrintTo("*errout*", "ErrorInner:   option context must be a local variables bag\n");
@@ -267,9 +266,6 @@ BIND_GLOBAL("ErrorInner",
         fi;
         JUMP_TO_CATCH(3);
     fi;
-    if timeout <> fail then
-       RESUME_TIMEOUT(timeout);
-    fi;
     if Length(res) > 0 then
         return res[1];
     else

hpcgap/lib/read3.g

@@ -245,8 +245,5 @@ ReadLib("proto.gd");
 
 ReadLib("gasman.gd");
 
-# files dealing with function calling
-ReadLib("function.gd");
-
 # random sources
 ReadLib("random.gi");

hpcgap/lib/system.g

@@ -520,23 +520,6 @@ BIND_GLOBAL("ARCH_IS_UNIX",function()
   return not ARCH_IS_WINDOWS();
 end);
 
-#############################################################################
-##
-#V  GAPInfo.TimeoutsSupported
-##
-##  <#GAPDoc Label="GAPInfo.TimeoutsSupported">
-##  <ManSection>
-##  <Var Name="GAPInfo.TimeoutsSupported"/>
-##
-## <Description>
-##  tests whether this installation of &GAP; supports the timeout functionality
-## of <Ref Func="CallWithTimeout"/> and related functions. 
-##  </Description>
-##  </ManSection>
-##  <#/GAPDoc>
-
-GAPInfo.TimeoutsSupported := TIMEOUTS_SUPPORTED();
-
 #############################################################################
 ##
 #V  GAPInfo.InitFiles

hpcgap/src/stats.c

@@ -1676,19 +1676,6 @@ sig_atomic_t volatile RealExecStatCopied;
 int volatile RealExecStatCopied;
 #endif
 
-/****************************************************************************
-**
-*F  void CheckAndRespondToAlarm()
-**
-*/
-
-static void CheckAndRespondToAlarm(void) {
-  if ( SyAlarmHasGoneOff ) {
-    assert(NumAlarmJumpBuffers);
-    syLongjmp(&(AlarmJumpBuffers[--NumAlarmJumpBuffers]),1);
-  }
-}
-
 /****************************************************************************
 **
 *F  UInt TakeInterrupt() . . . . . . . . allow user interrupts
@@ -1707,7 +1694,6 @@ UInt TakeInterrupt( void ) {
   if (STATE(CurrExecStatFuncs) == IntrExecStatFuncs) {
       assert(STATE(CurrExecStatFuncs) != ExecStatFuncs);
       STATE(CurrExecStatFuncs) = ExecStatFuncs;
-      CheckAndRespondToAlarm();
       ErrorReturnVoid( "user interrupt", 0L, 0L, "you can 'return;'" );
       return 1;
   }
@@ -1732,10 +1718,6 @@ UInt ExecIntrStat (
     /* change the entries in 'ExecStatFuncs' back to the original          */
     STATE(CurrExecStatFuncs) = ExecStatFuncs;
 
-    /* One reason we might be here is a timeout. If so longjump out to the 
-       CallWithTimeLimit where we started */
-    CheckAndRespondToAlarm();
-
     /* and now for something completely different                          */
     HandleInterrupts(1, stat);
 

lib/error.g

@@ -110,10 +110,9 @@ Unbind(ErrorInner);
 BIND_GLOBAL("ErrorInner",
         function( arg )
     local   context, mayReturnVoid,  mayReturnObj,  lateMessage,  earlyMessage,  
-            x,  prompt,  res, errorLVars, justQuit, printThisStatement, timeout,
+            x,  prompt,  res, errorLVars, justQuit, printThisStatement,
             location;
 
-    timeout := STOP_TIMEOUT();
 	context := arg[1].context;
     if not IsLVarsBag(context) then
         PrintTo("*errout*", "ErrorInner:   option context must be a local variables bag\n");
@@ -255,9 +254,6 @@ BIND_GLOBAL("ErrorInner",
         fi;
         JUMP_TO_CATCH(3);
     fi;
-    if timeout <> fail then
-       RESUME_TIMEOUT(timeout);
-    fi;
     if Length(res) > 0 then
         return res[1];
     else

lib/function.gi

@@ -5,76 +5,11 @@
 ##
 #Y  Copyright (C) 2015 The GAP Group
 ##
- ##  This file contains the implementations of the functions and operations
+##  This file contains the implementations of the functions and operations
 ##  relating to functions and function-calling which are not so basic
 ##  that they need to be in function.g
 ##
 
-
-#############################################################################
-##
-#F  CallWithTimeout( <timeout>, <func>[, <arg1>[, <arg2>....]] )  
-##         . . call a function with a time limit
-#F  CallWithTimeoutList( <timeout>, <func>, <arglist> )  
-##
-##
-
-InstallGlobalFunction(CallWithTimeout, 
-        function( timeout, func, arg... )
-    return CallWithTimeoutList(timeout, func, arg);
-end );
-
-InstallGlobalFunction("CallWithTimeoutList",
-        function(timeout, func, arglist )
-    local  process, nano, seconds, microseconds;
-    process := function(name, scale)
-        local  val;
-        if IsBound(timeout.(name)) then
-            val := timeout.(name);
-            if IsRat(val) or IsFloat(val) then
-                nano := nano + Int(val*scale);
-            else
-                Error("CallWithTimeout[List]: can't understand period of ",val," ",name,". Ignoring.");
-            fi;
-        fi;
-    end;
-    if not GAPInfo.TimeoutsSupported then
-        Error("Calling with time limits not supported in this GAP installation");
-        return fail;
-    fi;
-    if IsInt(timeout) then
-        nano := 1000*timeout;
-    else
-        if not IsRecord(timeout) then
-            Error("CallWithTimeout[List]: timeout must be an integer or record");
-            return fail;
-        fi;
-        nano := 0;
-        process("nanoseconds",1);
-        process("microseconds",1000);
-        process("milliseconds",1000000);
-        process("seconds",10^9);
-        process("minutes",60*10^9);
-        process("hours",3600*10^9);
-        process("days",24*3600*10^9);
-        process("weeks",7*24*3600*10^9);
-    fi;
-    if nano < 0 then
-        Error("Negative timeout is not permitted");
-        return fail;
-    fi;
-    seconds := QuoInt(nano, 10^9);
-    microseconds := QuoInt(nano mod 10^9, 1000);
-    if seconds = 0 and microseconds = 0 then
-        # zero or tiny timeout. just simulate timeout now
-        return fail;
-    fi;
-    # make sure it's a small int. Cap timeouts at about 8 years on
-    # 32 bit systems
-    seconds := Minimum(seconds,2^(8*GAPInfo.BytesPerVariable-4)-1);
-    return CALL_WITH_TIMEOUT(seconds, microseconds, func, arglist);
-end);
-
 InstallMethod( ViewString, "for a function", true, [IsFunction], 0,
 function(func)
     local  locks, nams, narg, i, isvarg, result;

lib/read3.g

@@ -247,8 +247,5 @@ ReadLib("gasman.gd");
 
 ReadLib("memusage.gd");
 
-# files dealing with function calling
-ReadLib("function.gd");
-
 # random sources
 ReadLib("random.gi");

lib/system.g

@@ -514,23 +514,6 @@ BIND_GLOBAL("ARCH_IS_UNIX",function()
   return not ARCH_IS_WINDOWS();
 end);
 
-#############################################################################
-##
-#V  GAPInfo.TimeoutsSupported
-##
-##  <#GAPDoc Label="GAPInfo.TimeoutsSupported">
-##  <ManSection>
-##  <Var Name="GAPInfo.TimeoutsSupported"/>
-##
-## <Description>
-##  tests whether this installation of &GAP; supports the timeout functionality
-## of <Ref Func="CallWithTimeout"/> and related functions. 
-##  </Description>
-##  </ManSection>
-##  <#/GAPDoc>
-
-GAPInfo.TimeoutsSupported := TIMEOUTS_SUPPORTED();
-
 #############################################################################
 ##
 #V  GAPInfo.InitFiles