/*

 * Copyright (c) 2003, 2016, Oracle and/or its affiliates. All rights reserved.

 * Copyright 2007, 2008, 2009, 2010 Red Hat, Inc.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#if !defined(__APPLE__) && !defined(__NetBSD__)

#include <pthread.h>

# include <pthread_np.h> /* For pthread_attr_get_np */

#endif

// no precompiled headers

#include "assembler_zero.inline.hpp"

#include "classfile/classLoader.hpp"

#include "classfile/systemDictionary.hpp"

#include "classfile/vmSymbols.hpp"

#include "code/icBuffer.hpp"

#include "code/vtableStubs.hpp"

#include "interpreter/interpreter.hpp"

#include "jvm_bsd.h"

#include "memory/allocation.inline.hpp"

#include "mutex_bsd.inline.hpp"

#include "nativeInst_zero.hpp"

#include "os_share_bsd.hpp"

#include "prims/jniFastGetField.hpp"

#include "prims/jvm.h"

#include "prims/jvm_misc.hpp"

#include "runtime/arguments.hpp"

#include "runtime/extendedPC.hpp"

#include "runtime/frame.inline.hpp"

#include "runtime/interfaceSupport.hpp"

#include "runtime/java.hpp"

#include "runtime/javaCalls.hpp"

#include "runtime/mutexLocker.hpp"

#include "runtime/osThread.hpp"

#include "runtime/sharedRuntime.hpp"

#include "runtime/stubRoutines.hpp"

#include "runtime/thread.inline.hpp"

#include "runtime/timer.hpp"

#include "utilities/events.hpp"

#include "utilities/vmError.hpp"

// See stubGenerator_zero.cpp

#include <setjmp.h>

extern sigjmp_buf* get_jmp_buf_for_continuation();

address os::current_stack_pointer() {

  address dummy = (address) &dummy;

  return dummy;

}

frame os::get_sender_for_C_frame(frame* fr) {

  ShouldNotCallThis();

  return frame();

}

frame os::current_frame() {

  // The only thing that calls this is the stack printing code in

  // VMError::report:

  //   - Step 110 (printing stack bounds) uses the sp in the frame

  //     to determine the amount of free space on the stack.  We

  //     set the sp to a close approximation of the real value in

  //     order to allow this step to complete.

  //   - Step 120 (printing native stack) tries to walk the stack.

  //     The frame we create has a NULL pc, which is ignored as an

  //     invalid frame.

  frame dummy = frame();

  dummy.set_sp((intptr_t *) current_stack_pointer());

  return dummy;

}

char* os::non_memory_address_word() {

  // Must never look like an address returned by reserve_memory,

  // even in its subfields (as defined by the CPU immediate fields,

  // if the CPU splits constants across multiple instructions).

#ifdef SPARC

  // On SPARC, 0 != %hi(any real address), because there is no

  // allocation in the first 1Kb of the virtual address space.

  return (char *) 0;

#else

  // This is the value for x86; works pretty well for PPC too.

  return (char *) -1;

#endif // SPARC

}

void os::initialize_thread(Thread* thr) {

  // Nothing to do.

}

address os::Bsd::ucontext_get_pc(const ucontext_t* uc) {

  ShouldNotCallThis();

  return NULL;

}

void os::Bsd::ucontext_set_pc(ucontext_t * uc, address pc) {

  ShouldNotCallThis();

}

ExtendedPC os::fetch_frame_from_context(const void* ucVoid,

                                        intptr_t** ret_sp,

                                        intptr_t** ret_fp) {

  ShouldNotCallThis();

  return ExtendedPC();

}

frame os::fetch_frame_from_context(const void* ucVoid) {

  ShouldNotCallThis();

  return frame();

}

extern "C" JNIEXPORT int

JVM_handle_bsd_signal(int sig,

                        siginfo_t* info,

                        void* ucVoid,

                        int abort_if_unrecognized) {

  ucontext_t* uc = (ucontext_t*) ucVoid;

  Thread* t = Thread::current_or_null_safe();

  SignalHandlerMark shm(t);

  // handle SafeFetch faults

  if (sig == SIGSEGV || sig == SIGBUS) {

    sigjmp_buf* const pjb = get_jmp_buf_for_continuation();

    if (pjb) {

      siglongjmp(*pjb, 1);

    }

  }

  // Note: it's not uncommon that JNI code uses signal/sigset to

  // install then restore certain signal handler (e.g. to temporarily

  // block SIGPIPE, or have a SIGILL handler when detecting CPU

  // type). When that happens, JVM_handle_bsd_signal() might be

  // invoked with junk info/ucVoid. To avoid unnecessary crash when

  // libjsig is not preloaded, try handle signals that do not require

  // siginfo/ucontext first.

  if (sig == SIGPIPE || sig == SIGXFSZ) {

    // allow chained handler to go first

    if (os::Bsd::chained_handler(sig, info, ucVoid)) {

      return true;

    } else {

      // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219

      return true;

    }

  }

  JavaThread* thread = NULL;

  VMThread* vmthread = NULL;

  if (os::Bsd::signal_handlers_are_installed) {

    if (t != NULL ){

      if(t->is_Java_thread()) {

        thread = (JavaThread*)t;

      }

      else if(t->is_VM_thread()){

        vmthread = (VMThread *)t;

      }

    }

  }

  if (info != NULL && thread != NULL) {

    // Handle ALL stack overflow variations here

    if (sig == SIGSEGV || sig == SIGBUS) {

      address addr = (address) info->si_addr;

      // check if fault address is within thread stack

      if (thread->on_local_stack(addr)) {

        // stack overflow

        if (thread->in_stack_yellow_reserved_zone(addr)) {

          thread->disable_stack_yellow_reserved_zone();

          ShouldNotCallThis();

        }

        else if (thread->in_stack_red_zone(addr)) {

          thread->disable_stack_red_zone();

          ShouldNotCallThis();

        }

      }

    }

    /*if (thread->thread_state() == _thread_in_Java) {

      ShouldNotCallThis();

    }

    else*/ if (thread->thread_state() == _thread_in_vm &&

               sig == SIGBUS && thread->doing_unsafe_access()) {

      ShouldNotCallThis();

    }

    // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC

    // kicks in and the heap gets shrunk before the field access.

    /*if (sig == SIGSEGV || sig == SIGBUS) {

      address addr = JNI_FastGetField::find_slowcase_pc(pc);

      if (addr != (address)-1) {

        stub = addr;

      }

    }*/

    // Check to see if we caught the safepoint code in the process

    // of write protecting the memory serialization page.  It write

    // enables the page immediately after protecting it so we can

    // just return to retry the write.

    if ((sig == SIGSEGV || sig == SIGBUS) &&

        os::is_memory_serialize_page(thread, (address) info->si_addr)) {

      // Block current thread until permission is restored.

      os::block_on_serialize_page_trap();

      return true;

    }

  }

  // signal-chaining

  if (os::Bsd::chained_handler(sig, info, ucVoid)) {

     return true;

  }

  if (!abort_if_unrecognized) {

    // caller wants another chance, so give it to him

    return false;

  }

#ifndef PRODUCT

  if (sig == SIGSEGV) {

    fatal("\n#"

          "\n#    /--------------------\\"

          "\n#    | segmentation fault |"

          "\n#    \\---\\ /--------------/"

          "\n#        /"

          "\n#    [-]        |\\_/|    "

          "\n#    (+)=C      |o o|__  "

          "\n#    | |        =-*-=__\\ "

          "\n#    OOO        c_c_(___)");

  }

#endif // !PRODUCT

  const char *fmt =

      "caught unhandled signal " INT32_FORMAT " at address " PTR_FORMAT;

  char buf[128];

  sprintf(buf, fmt, sig, info->si_addr);

  fatal(buf);

  return false;

}

void os::Bsd::init_thread_fpu_state(void) {

  // Nothing to do

}

bool os::is_allocatable(size_t bytes) {

#ifdef _LP64

  return true;

#else

  if (bytes < 2 * G) {

    return true;

  }

  char* addr = reserve_memory(bytes, NULL);

  if (addr != NULL) {

    release_memory(addr, bytes);

  }

  return addr != NULL;

#endif // _LP64

}

///////////////////////////////////////////////////////////////////////////////

// thread stack

size_t os::Bsd::min_stack_allowed = 64 * K;

size_t os::Bsd::default_stack_size(os::ThreadType thr_type) {

#ifdef _LP64

  size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);

#else

  size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);

#endif // _LP64

  return s;

}

size_t os::Bsd::default_guard_size(os::ThreadType thr_type) {

  // Only enable glibc guard pages for non-Java threads

  // (Java threads have HotSpot guard pages)

  return (thr_type == java_thread ? 0 : page_size());

}

static void current_stack_region(address *bottom, size_t *size) {

  address stack_bottom;

  address stack_top;

  size_t stack_bytes;

#ifdef __APPLE__

  pthread_t self = pthread_self();

  stack_top = (address) pthread_get_stackaddr_np(self);

  stack_bytes = pthread_get_stacksize_np(self);

  stack_bottom = stack_top - stack_bytes;

#elif defined(__OpenBSD__)

  stack_t ss;

  int rslt = pthread_stackseg_np(pthread_self(), &ss);

  if (rslt != 0)

    fatal("pthread_stackseg_np failed with err = " INT32_FORMAT, rslt);

  stack_top = (address) ss.ss_sp;

  stack_bytes  = ss.ss_size;

  stack_bottom = stack_top - stack_bytes;

#else

  pthread_attr_t attr;

  int rslt = pthread_attr_init(&attr);

  // JVM needs to know exact stack location, abort if it fails

  if (rslt != 0)

    fatal("pthread_attr_init failed with err = " INT32_FORMAT, rslt);

  rslt = pthread_attr_get_np(pthread_self(), &attr);

  if (rslt != 0)

    fatal("pthread_attr_get_np failed with err = " INT32_FORMAT, rslt);

  if (pthread_attr_getstackaddr(&attr, (void **) &stack_bottom) != 0 ||

      pthread_attr_getstacksize(&attr, &stack_bytes) != 0) {

    fatal("Can not locate current stack attributes!");

  }

  pthread_attr_destroy(&attr);

  stack_top = stack_bottom + stack_bytes;

#endif

  assert(os::current_stack_pointer() >= stack_bottom, "should do");

  assert(os::current_stack_pointer() < stack_top, "should do");

  *bottom = stack_bottom;

  *size = stack_top - stack_bottom;

}

address os::current_stack_base() {

  address bottom;

  size_t size;

  current_stack_region(&bottom, &size);

  return bottom + size;

}

size_t os::current_stack_size() {

  // stack size includes normal stack and HotSpot guard pages

  address bottom;

  size_t size;

  current_stack_region(&bottom, &size);

  return size;

}

/////////////////////////////////////////////////////////////////////////////

// helper functions for fatal error handler

void os::print_context(outputStream* st, const void* context) {

  ShouldNotCallThis();

}

void os::print_register_info(outputStream *st, const void *context) {

  ShouldNotCallThis();

}

/////////////////////////////////////////////////////////////////////////////

// Stubs for things that would be in bsd_zero.s if it existed.

// You probably want to disassemble these monkeys to check they're ok.

extern "C" {

  int SpinPause() {

    return 1;

  }

  void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {

    if (from > to) {

      jshort *end = from + count;

      while (from < end)

        *(to++) = *(from++);

    }

    else if (from < to) {

      jshort *end = from;

      from += count - 1;

      to   += count - 1;

      while (from >= end)

        *(to--) = *(from--);

    }

  }

  void _Copy_conjoint_jints_atomic(jint* from, jint* to, size_t count) {

    if (from > to) {

      jint *end = from + count;

      while (from < end)

        *(to++) = *(from++);

    }

    else if (from < to) {

      jint *end = from;

      from += count - 1;

      to   += count - 1;

      while (from >= end)

        *(to--) = *(from--);

    }

  }

  void _Copy_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {

    if (from > to) {

      jlong *end = from + count;

      while (from < end)

        os::atomic_copy64(from++, to++);

    }

    else if (from < to) {

      jlong *end = from;

      from += count - 1;

      to   += count - 1;

      while (from >= end)

        os::atomic_copy64(from--, to--);

    }

  }

  void _Copy_arrayof_conjoint_bytes(HeapWord* from,

                                    HeapWord* to,

                                    size_t    count) {

    memmove(to, from, count);

  }

  void _Copy_arrayof_conjoint_jshorts(HeapWord* from,

                                      HeapWord* to,

                                      size_t    count) {

    memmove(to, from, count * 2);

  }

  void _Copy_arrayof_conjoint_jints(HeapWord* from,

                                    HeapWord* to,

                                    size_t    count) {

    memmove(to, from, count * 4);

  }

  void _Copy_arrayof_conjoint_jlongs(HeapWord* from,

                                     HeapWord* to,

                                     size_t    count) {

    memmove(to, from, count * 8);

  }

};

/////////////////////////////////////////////////////////////////////////////

// Implementations of atomic operations not supported by processors.

//  -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html

#ifndef _LP64

extern "C" {

  long long unsigned int __sync_val_compare_and_swap_8(

    volatile void *ptr,

    long long unsigned int oldval,

    long long unsigned int newval) {

    ShouldNotCallThis();

  }

};

#endif // !_LP64

#ifndef PRODUCT

void os::verify_stack_alignment() {

}

#endif

int os::extra_bang_size_in_bytes() {

  // Zero does not require an additional stack bang.

  return 0;

}