// natSystem.cc - Native code implementing System class.

/* Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation

   This file is part of libgcj.

This software is copyrighted work licensed under the terms of the
Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
details.  */

#include <config.h>
#include <platform.h>

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include <gcj/cni.h>
#include <jvm.h>
#include <java/lang/System.h>
#include <java/lang/Class.h>
#include <java/lang/ArrayStoreException.h>
#include <java/lang/ArrayIndexOutOfBoundsException.h>
#include <java/lang/NullPointerException.h>
#include <java/io/PrintStream.h>
#include <java/io/InputStream.h>



void
java::lang::System::setErr0 (java::io::PrintStream *newErr)
{
  err = newErr;
}

void
java::lang::System::setIn0 (java::io::InputStream *newIn)
{
  in = newIn;
}

void
java::lang::System::setOut0 (java::io::PrintStream *newOut)
{
  out = newOut;
}

void
java::lang::System::arraycopy (jobject src, jint src_offset,
			       jobject dst, jint dst_offset,
			       jint count)
{
  if (! src || ! dst)
    throw new NullPointerException;

  jclass src_c = src->getClass();
  jclass dst_c = dst->getClass();
  jclass src_comp = src_c->getComponentType();
  jclass dst_comp = dst_c->getComponentType();

  if (! src_c->isArray() || ! dst_c->isArray()
      || src_comp->isPrimitive() != dst_comp->isPrimitive()
      || (src_comp->isPrimitive() && src_comp != dst_comp))
    throw new ArrayStoreException;

  __JArray *src_a = (__JArray *) src;
  __JArray *dst_a = (__JArray *) dst;
  if (src_offset < 0 || dst_offset < 0 || count < 0
      || (unsigned jint) src_offset > (unsigned jint) src_a->length
      || (unsigned jint) (src_offset + count) > (unsigned jint) src_a->length
      || (unsigned jint) dst_offset > (unsigned jint) dst_a->length
      || (unsigned jint) (dst_offset + count) > (unsigned jint) dst_a->length)
    throw new ArrayIndexOutOfBoundsException;

  // Do-nothing cases.
  if ((src == dst && src_offset == dst_offset)
      || ! count)
    return;

  // If both are primitive, we can optimize trivially.  If DST
  // components are always assignable from SRC components, then we
  // will never need to raise an error, and thus can do the
  // optimization.  If source and destinations are the same, then we
  // know that the assignability premise always holds.
  const bool prim = src_comp->isPrimitive();
  if (prim || dst_comp->isAssignableFrom(src_comp) || src == dst)
    {
      const size_t size = (prim ? src_comp->size()
			   : sizeof elements((jobjectArray)src)[0]);

      char *src_elts = _Jv_GetArrayElementFromElementType (src, src_comp);
      src_elts += size * src_offset;

      char *dst_elts = _Jv_GetArrayElementFromElementType (dst, dst_comp);
      dst_elts += size * dst_offset;

#if HAVE_MEMMOVE
      // We don't bother trying memcpy.  It can't be worth the cost of
      // the check.
      // Don't cast to (void*), as memmove may expect (char*)
      memmove (dst_elts, src_elts, count * size);
#else
      bcopy (src_elts, dst_elts, count * size);
#endif
    }
  else
    {
      jobject *src_elts = elements ((jobjectArray) src_a) + src_offset;
      jobject *dst_elts = elements ((jobjectArray) dst_a) + dst_offset;

      for (int i = 0; i < count; ++i)
	{
	  if (*src_elts
	      && ! dst_comp->isAssignableFrom((*src_elts)->getClass()))
	    throw new ArrayStoreException;
	  *dst_elts++ = *src_elts++;
	}
    }
}

jlong
java::lang::System::currentTimeMillis (void)
{
  return _Jv_platform_gettimeofday ();
}

jint
java::lang::System::identityHashCode (jobject obj)
{
  return _Jv_HashCode (obj);
}

jboolean
java::lang::System::isWordsBigEndian (void)
{
  union
  {
    long lval;
    char cval;
  } u;

  u.lval = 1;
  return u.cval == 0;
}

jstring
java::lang::System::getenv0 (jstring name)
{
  jint len = _Jv_GetStringUTFLength (name);
  char buf[len + 1];
  jsize total = JvGetStringUTFRegion (name, 0, name->length(), buf);
  buf[total] = '\0';
  const char *value = ::getenv (buf);
  if (value == NULL)
    return NULL;
  return JvNewStringUTF (value);
}