path: root/ghc/rts/RtsAPI.c

/* ----------------------------------------------------------------------------
 * $Id: RtsAPI.c,v 1.18 2000/08/07 23:37:23 qrczak Exp $
 *
 * (c) The GHC Team, 1998-2000
 *
 * API for invoking Haskell functions via the RTS
 *
 * --------------------------------------------------------------------------*/

#include "Rts.h"
#include "Storage.h"
#include "RtsAPI.h"
#include "SchedAPI.h"
#include "RtsFlags.h"
#include "RtsUtils.h"
#include "Prelude.h"

/* ----------------------------------------------------------------------------
   Building Haskell objects from C datatypes.
   ------------------------------------------------------------------------- */
HaskellObj
rts_mkChar (unsigned int c)
{
  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,1));
  p->header.info = Czh_con_info;
  p->payload[0]  = (StgClosure *)(StgChar)c;
  return p;
}

HaskellObj
rts_mkInt (int i)
{
  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,1));
  p->header.info = Izh_con_info;
  p->payload[0]  = (StgClosure *)(StgInt)i;
  return p;
}

HaskellObj
rts_mkInt8 (int i)
{
  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,1));
  /* This is a 'cheat', using the static info table for Ints,
     instead of the one for Int8, but the types have identical
     representation.
  */
  p->header.info = Izh_con_info;
  /* Make sure we mask out the bits above the lowest 8 */
  p->payload[0]  = (StgClosure *)(StgInt)((unsigned)i & 0xff);
  return p;
}

HaskellObj
rts_mkInt16 (int i)
{
  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,1));
  /* This is a 'cheat', using the static info table for Ints,
     instead of the one for Int8, but the types have identical
     representation.
  */
  p->header.info = Izh_con_info;
  /* Make sure we mask out the relevant bits */
  p->payload[0]  = (StgClosure *)(StgInt)((unsigned)i & 0xffff);
  return p;
}

HaskellObj
rts_mkInt32 (int i)
{
  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,1));
  /* see mk_Int8 comment */
  p->header.info = Izh_con_info;
  p->payload[0]  = (StgClosure *)(StgInt)i;
  return p;
}

HaskellObj
rts_mkInt64 (long long int i)
{
  long long *tmp;
  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,2));
  /* see mk_Int8 comment */
  p->header.info = I64zh_con_info;
  tmp  = (long long*)&(p->payload[0]);
  *tmp = (StgInt64)i;
  return p;
}

HaskellObj
rts_mkWord (unsigned int i)
{
  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,1));
  p->header.info = Wzh_con_info;
  p->payload[0]  = (StgClosure *)(StgWord)i;
  return p;
}

HaskellObj
rts_mkWord8 (unsigned int w)
{
  /* see rts_mkInt* comments */
  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,1));
  p->header.info = Wzh_con_info;
  p->payload[0]  = (StgClosure *)(StgWord)(w & 0xff);
  return p;
}

HaskellObj
rts_mkWord16 (unsigned int w)
{
  /* see rts_mkInt* comments */
  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,1));
  p->header.info = Wzh_con_info;
  p->payload[0]  = (StgClosure *)(StgWord)(w & 0xffff);
  return p;
}

HaskellObj
rts_mkWord32 (unsigned int w)
{
  /* see rts_mkInt* comments */
  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,1));
  p->header.info = Wzh_con_info;
  p->payload[0]  = (StgClosure *)(StgWord)w;
  return p;
}

HaskellObj
rts_mkWord64 (unsigned long long w)
{
  unsigned long long *tmp;

  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,2));
  /* see mk_Int8 comment */
  p->header.info = W64zh_con_info;
  tmp  = (unsigned long long*)&(p->payload[0]);
  *tmp = (StgWord64)w;
  return p;
}

HaskellObj
rts_mkFloat (float f)
{
  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,1));
  p->header.info = Fzh_con_info;
  ASSIGN_FLT((P_)p->payload, (StgFloat)f);
  return p;
}

HaskellObj
rts_mkDouble (double d)
{
  StgClosure *p = (StgClosure *)allocate(CONSTR_sizeW(0,sizeofW(StgDouble)));
  p->header.info = Dzh_con_info;
  ASSIGN_DBL((P_)p->payload, (StgDouble)d);
  return p;
}

HaskellObj
rts_mkStablePtr (StgStablePtr s)
{
  StgClosure *p = (StgClosure *)allocate(sizeofW(StgHeader)+1);
  p->header.info = StablePtr_con_info;
  p->payload[0]  = (StgClosure *)s;
  return p;
}

HaskellObj
rts_mkAddr (void *a)
{
  StgClosure *p = (StgClosure *)allocate(sizeofW(StgHeader)+1);
  p->header.info = Azh_con_info;
  p->payload[0]  = (StgClosure *)a;
  return p;
}

#ifdef COMPILER /* GHC has em, Hugs doesn't */
HaskellObj
rts_mkBool (StgBool b)
{
  if (b) {
    return (StgClosure *)True_closure;
  } else {
    return (StgClosure *)False_closure;
  }
}

HaskellObj
rts_mkString (char *s)
{
  return rts_apply((StgClosure *)unpackCString_closure, rts_mkAddr(s));
}
#endif /* COMPILER */

HaskellObj
rts_apply (HaskellObj f, HaskellObj arg)
{
  StgAP_UPD *ap = (StgAP_UPD *)allocate(AP_sizeW(1));
  SET_HDR(ap, &AP_UPD_info, CCS_SYSTEM);
  ap->n_args = 1;
  ap->fun    = f;
  ap->payload[0] = (P_)arg;
  return (StgClosure *)ap;
}

/* ----------------------------------------------------------------------------
   Deconstructing Haskell objects
   ------------------------------------------------------------------------- */

unsigned int
rts_getChar (HaskellObj p)
{
  if ( p->header.info == Czh_con_info || 
       p->header.info == Czh_static_info) {
    return (StgChar)(StgWord)(p->payload[0]);
  } else {
    barf("getChar: not a Char");
  }
}

int
rts_getInt (HaskellObj p)
{
  if ( 1 ||
       p->header.info == Izh_con_info || 
       p->header.info == Izh_static_info ) {
    return (int)(p->payload[0]);
  } else {
    barf("getInt: not an Int");
  }
}

int
rts_getInt32 (HaskellObj p)
{
  if ( 1 ||
       p->header.info == Izh_con_info || 
       p->header.info == Izh_static_info ) {
    return (int)(p->payload[0]);
  } else {
    barf("getInt: not an Int");
  }
}

unsigned int
rts_getWord (HaskellObj p)
{
  if ( 1 || /* see above comment */
       p->header.info == Wzh_con_info ||
       p->header.info == Wzh_static_info ) {
    return (unsigned int)(p->payload[0]);
  } else {
    barf("getWord: not a Word");
  }
}

unsigned int
rts_getWord32 (HaskellObj p)
{
  if ( 1 || /* see above comment */
       p->header.info == Wzh_con_info ||
       p->header.info == Wzh_static_info ) {
    return (unsigned int)(p->payload[0]);
  } else {
    barf("getWord: not a Word");
  }
}

float
rts_getFloat (HaskellObj p)
{
  if ( p->header.info == Fzh_con_info || 
       p->header.info == Fzh_static_info ) {
    return (float)(PK_FLT((P_)p->payload));
  } else {
    barf("getFloat: not a Float");
  }
}

double
rts_getDouble (HaskellObj p)
{
  if ( p->header.info == Dzh_con_info || 
       p->header.info == Dzh_static_info ) {
    return (double)(PK_DBL((P_)p->payload));
  } else {
    barf("getDouble: not a Double");
  }
}

StgStablePtr
rts_getStablePtr (HaskellObj p)
{
  if ( p->header.info == StablePtr_con_info || 
       p->header.info == StablePtr_static_info ) {
    return (StgStablePtr)(p->payload[0]);
  } else {
    barf("getStablePtr: not a StablePtr");
  }
}

void *
rts_getAddr (HaskellObj p)
{
  if ( p->header.info == Azh_con_info || 
       p->header.info == Azh_static_info ) {
  
    return (void *)(p->payload[0]);
  } else {
    barf("getAddr: not an Addr");
  }
}

#ifdef COMPILER /* GHC has em, Hugs doesn't */
int
rts_getBool (HaskellObj p)
{
  if (p == True_closure) {
    return 1;
  } else if (p == False_closure) {
    return 0;
  } else {
    barf("getBool: not a Bool");
  }
}
#endif /* COMPILER */

/* ----------------------------------------------------------------------------
   Evaluating Haskell expressions
   ------------------------------------------------------------------------- */
SchedulerStatus
rts_eval (HaskellObj p, /*out*/HaskellObj *ret)
{
  StgTSO *tso = createGenThread(RtsFlags.GcFlags.initialStkSize, p);
  scheduleThread(tso);
  return waitThread(tso, ret);
}

SchedulerStatus
rts_eval_ (HaskellObj p, unsigned int stack_size, /*out*/HaskellObj *ret)
{
  StgTSO *tso = createGenThread(stack_size, p);
  scheduleThread(tso);
  return waitThread(tso, ret);
}

/*
 * rts_evalIO() evaluates a value of the form (IO a), forcing the action's
 * result to WHNF before returning.
 */
SchedulerStatus
rts_evalIO (HaskellObj p, /*out*/HaskellObj *ret)
{
  StgTSO* tso = createStrictIOThread(RtsFlags.GcFlags.initialStkSize, p);
  scheduleThread(tso);
  return waitThread(tso, ret);
}

/*
 * Like rts_evalIO(), but doesn't force the action's result.
 */
SchedulerStatus
rts_evalLazyIO (HaskellObj p, unsigned int stack_size, /*out*/HaskellObj *ret)
{
  StgTSO *tso = createIOThread(stack_size, p);
  scheduleThread(tso);
  return waitThread(tso, ret);
}

#if defined(PAR) || defined(SMP)
/*
  Needed in the parallel world for non-Main PEs, which do not get a piece
  of work to start with --- they have to humbly ask for it
*/

SchedulerStatus
rts_evalNothing(unsigned int stack_size)
{
  /* ToDo: propagate real SchedulerStatus back to caller */
  scheduleThread(END_TSO_QUEUE);
  return Success;
}
#endif

/* Convenience function for decoding the returned status. */

void
rts_checkSchedStatus ( char* site, SchedulerStatus rc )
{
    switch (rc) {
    case Success:
	return;
    case Killed:
	barf("%s: uncaught exception",site);
    case Interrupted:
	barf("%s: interrupted", site);
    case Deadlock:
	barf("%s: no threads to run:  infinite loop or deadlock?", site);
    default:
	barf("%s: Return code (%d) not ok",(site),(rc));	
    }
}