/*

 * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.

 * 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.

 *

 */

// no precompiled headers

#include "jvm.h"

#include "asm/macroAssembler.hpp"

#include "classfile/classLoader.hpp"

#include "classfile/systemDictionary.hpp"

#include "classfile/vmSymbols.hpp"

#include "code/codeCache.hpp"

#include "code/icBuffer.hpp"

#include "code/vtableStubs.hpp"

#include "interpreter/interpreter.hpp"

#include "logging/log.hpp"

#include "memory/allocation.inline.hpp"

#include "os_share_bsd.hpp"

#include "prims/jniFastGetField.hpp"

#include "prims/jvm_misc.hpp"

#include "runtime/arguments.hpp"

#include "runtime/extendedPC.hpp"

#include "runtime/frame.inline.hpp"

#include "runtime/interfaceSupport.inline.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/align.hpp"

#include "utilities/events.hpp"

#include "utilities/vmError.hpp"

// put OS-includes here

# include <sys/types.h>

# include <sys/mman.h>

# include <pthread.h>

# include <signal.h>

# include <errno.h>

# include <dlfcn.h>

# include <stdlib.h>

# include <stdio.h>

# include <unistd.h>

# include <sys/resource.h>

# include <pthread.h>

# include <sys/stat.h>

# include <sys/time.h>

# include <sys/utsname.h>

# include <sys/socket.h>

# include <sys/wait.h>

# include <pwd.h>

# include <poll.h>

#ifndef __OpenBSD__

# include <ucontext.h>

#endif

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

# include <pthread_np.h>

#endif

// needed by current_stack_region() workaround for Mavericks

#if defined(__APPLE__)

# include <errno.h>

# include <sys/types.h>

# include <sys/sysctl.h>

# define DEFAULT_MAIN_THREAD_STACK_PAGES 2048

# define OS_X_10_9_0_KERNEL_MAJOR_VERSION 13

#endif

#ifdef AMD64

#define SPELL_REG_SP "rsp"

#define SPELL_REG_FP "rbp"

#else

#define SPELL_REG_SP "esp"

#define SPELL_REG_FP "ebp"

#endif // AMD64

#ifdef __FreeBSD__

# define context_trapno uc_mcontext.mc_trapno

# ifdef AMD64

#  define context_pc uc_mcontext.mc_rip

#  define context_sp uc_mcontext.mc_rsp

#  define context_fp uc_mcontext.mc_rbp

#  define context_rip uc_mcontext.mc_rip

#  define context_rsp uc_mcontext.mc_rsp

#  define context_rbp uc_mcontext.mc_rbp

#  define context_rax uc_mcontext.mc_rax

#  define context_rbx uc_mcontext.mc_rbx

#  define context_rcx uc_mcontext.mc_rcx

#  define context_rdx uc_mcontext.mc_rdx

#  define context_rsi uc_mcontext.mc_rsi

#  define context_rdi uc_mcontext.mc_rdi

#  define context_r8  uc_mcontext.mc_r8

#  define context_r9  uc_mcontext.mc_r9

#  define context_r10 uc_mcontext.mc_r10

#  define context_r11 uc_mcontext.mc_r11

#  define context_r12 uc_mcontext.mc_r12

#  define context_r13 uc_mcontext.mc_r13

#  define context_r14 uc_mcontext.mc_r14

#  define context_r15 uc_mcontext.mc_r15

#  define context_flags uc_mcontext.mc_flags

#  define context_err uc_mcontext.mc_err

# else

#  define context_pc uc_mcontext.mc_eip

#  define context_sp uc_mcontext.mc_esp

#  define context_fp uc_mcontext.mc_ebp

#  define context_eip uc_mcontext.mc_eip

#  define context_esp uc_mcontext.mc_esp

#  define context_eax uc_mcontext.mc_eax

#  define context_ebx uc_mcontext.mc_ebx

#  define context_ecx uc_mcontext.mc_ecx

#  define context_edx uc_mcontext.mc_edx

#  define context_ebp uc_mcontext.mc_ebp

#  define context_esi uc_mcontext.mc_esi

#  define context_edi uc_mcontext.mc_edi

#  define context_eflags uc_mcontext.mc_eflags

#  define context_trapno uc_mcontext.mc_trapno

# endif

#endif

#ifdef __APPLE__

# if __DARWIN_UNIX03 && (MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5)

  // 10.5 UNIX03 member name prefixes

  #define DU3_PREFIX(s, m) __ ## s.__ ## m

# else

  #define DU3_PREFIX(s, m) s ## . ## m

# endif

# ifdef AMD64

#  define context_pc context_rip

#  define context_sp context_rsp

#  define context_fp context_rbp

#  define context_rip uc_mcontext->DU3_PREFIX(ss,rip)

#  define context_rsp uc_mcontext->DU3_PREFIX(ss,rsp)

#  define context_rax uc_mcontext->DU3_PREFIX(ss,rax)

#  define context_rbx uc_mcontext->DU3_PREFIX(ss,rbx)

#  define context_rcx uc_mcontext->DU3_PREFIX(ss,rcx)

#  define context_rdx uc_mcontext->DU3_PREFIX(ss,rdx)

#  define context_rbp uc_mcontext->DU3_PREFIX(ss,rbp)

#  define context_rsi uc_mcontext->DU3_PREFIX(ss,rsi)

#  define context_rdi uc_mcontext->DU3_PREFIX(ss,rdi)

#  define context_r8  uc_mcontext->DU3_PREFIX(ss,r8)

#  define context_r9  uc_mcontext->DU3_PREFIX(ss,r9)

#  define context_r10 uc_mcontext->DU3_PREFIX(ss,r10)

#  define context_r11 uc_mcontext->DU3_PREFIX(ss,r11)

#  define context_r12 uc_mcontext->DU3_PREFIX(ss,r12)

#  define context_r13 uc_mcontext->DU3_PREFIX(ss,r13)

#  define context_r14 uc_mcontext->DU3_PREFIX(ss,r14)

#  define context_r15 uc_mcontext->DU3_PREFIX(ss,r15)

#  define context_flags uc_mcontext->DU3_PREFIX(ss,rflags)

#  define context_trapno uc_mcontext->DU3_PREFIX(es,trapno)

#  define context_err uc_mcontext->DU3_PREFIX(es,err)

# else

#  define context_pc context_eip

#  define context_sp context_esp

#  define context_fp context_ebp

#  define context_eip uc_mcontext->DU3_PREFIX(ss,eip)

#  define context_esp uc_mcontext->DU3_PREFIX(ss,esp)

#  define context_eax uc_mcontext->DU3_PREFIX(ss,eax)

#  define context_ebx uc_mcontext->DU3_PREFIX(ss,ebx)

#  define context_ecx uc_mcontext->DU3_PREFIX(ss,ecx)

#  define context_edx uc_mcontext->DU3_PREFIX(ss,edx)

#  define context_ebp uc_mcontext->DU3_PREFIX(ss,ebp)

#  define context_esi uc_mcontext->DU3_PREFIX(ss,esi)

#  define context_edi uc_mcontext->DU3_PREFIX(ss,edi)

#  define context_eflags uc_mcontext->DU3_PREFIX(ss,eflags)

#  define context_trapno uc_mcontext->DU3_PREFIX(es,trapno)

# endif

#endif

#ifdef __OpenBSD__

# define context_trapno sc_trapno

# ifdef AMD64

#  define context_pc sc_rip

#  define context_sp sc_rsp

#  define context_fp sc_rbp

#  define context_rip sc_rip

#  define context_rsp sc_rsp

#  define context_rbp sc_rbp

#  define context_rax sc_rax

#  define context_rbx sc_rbx

#  define context_rcx sc_rcx

#  define context_rdx sc_rdx

#  define context_rsi sc_rsi

#  define context_rdi sc_rdi

#  define context_r8  sc_r8

#  define context_r9  sc_r9

#  define context_r10 sc_r10

#  define context_r11 sc_r11

#  define context_r12 sc_r12

#  define context_r13 sc_r13

#  define context_r14 sc_r14

#  define context_r15 sc_r15

#  define context_flags sc_rflags

#  define context_err sc_err

# else

#  define context_pc sc_eip

#  define context_sp sc_esp

#  define context_fp sc_ebp

#  define context_eip sc_eip

#  define context_esp sc_esp

#  define context_eax sc_eax

#  define context_ebx sc_ebx

#  define context_ecx sc_ecx

#  define context_edx sc_edx

#  define context_ebp sc_ebp

#  define context_esi sc_esi

#  define context_edi sc_edi

#  define context_eflags sc_eflags

#  define context_trapno sc_trapno

# endif

#endif

#ifdef __NetBSD__

# define context_trapno uc_mcontext.__gregs[_REG_TRAPNO]

# ifdef AMD64

#  define __register_t __greg_t

#  define context_pc uc_mcontext.__gregs[_REG_RIP]

#  define context_sp uc_mcontext.__gregs[_REG_URSP]

#  define context_fp uc_mcontext.__gregs[_REG_RBP]

#  define context_rip uc_mcontext.__gregs[_REG_RIP]

#  define context_rsp uc_mcontext.__gregs[_REG_URSP]

#  define context_rax uc_mcontext.__gregs[_REG_RAX]

#  define context_rbx uc_mcontext.__gregs[_REG_RBX]

#  define context_rcx uc_mcontext.__gregs[_REG_RCX]

#  define context_rdx uc_mcontext.__gregs[_REG_RDX]

#  define context_rbp uc_mcontext.__gregs[_REG_RBP]

#  define context_rsi uc_mcontext.__gregs[_REG_RSI]

#  define context_rdi uc_mcontext.__gregs[_REG_RDI]

#  define context_r8  uc_mcontext.__gregs[_REG_R8]

#  define context_r9  uc_mcontext.__gregs[_REG_R9]

#  define context_r10 uc_mcontext.__gregs[_REG_R10]

#  define context_r11 uc_mcontext.__gregs[_REG_R11]

#  define context_r12 uc_mcontext.__gregs[_REG_R12]

#  define context_r13 uc_mcontext.__gregs[_REG_R13]

#  define context_r14 uc_mcontext.__gregs[_REG_R14]

#  define context_r15 uc_mcontext.__gregs[_REG_R15]

#  define context_flags uc_mcontext.__gregs[_REG_RFL]

#  define context_err uc_mcontext.__gregs[_REG_ERR]

# else

#  define context_pc uc_mcontext.__gregs[_REG_EIP]

#  define context_sp uc_mcontext.__gregs[_REG_UESP]

#  define context_fp uc_mcontext.__gregs[_REG_EBP]

#  define context_eip uc_mcontext.__gregs[_REG_EIP]

#  define context_esp uc_mcontext.__gregs[_REG_UESP]

#  define context_eax uc_mcontext.__gregs[_REG_EAX]

#  define context_ebx uc_mcontext.__gregs[_REG_EBX]

#  define context_ecx uc_mcontext.__gregs[_REG_ECX]

#  define context_edx uc_mcontext.__gregs[_REG_EDX]

#  define context_ebp uc_mcontext.__gregs[_REG_EBP]

#  define context_esi uc_mcontext.__gregs[_REG_ESI]

#  define context_edi uc_mcontext.__gregs[_REG_EDI]

#  define context_eflags uc_mcontext.__gregs[_REG_EFL]

#  define context_trapno uc_mcontext.__gregs[_REG_TRAPNO]

# endif

#endif

address os::current_stack_pointer() {

#if defined(__clang__) || defined(__llvm__)

  void *esp;

  __asm__("mov %%" SPELL_REG_SP ", %0":"=r"(esp));

  return (address) esp;

#elif defined(SPARC_WORKS)

  void *esp;

  __asm__("mov %%" SPELL_REG_SP ", %0":"=r"(esp));

  return (address) ((char*)esp + sizeof(long)*2);

#else

  register void *esp __asm__ (SPELL_REG_SP);

  return (address) esp;

#endif

}

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).

  return (char*) -1;

}

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

  return (address)uc->context_pc;

}

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

  uc->context_pc = (intptr_t)pc ;

}

intptr_t* os::Bsd::ucontext_get_sp(const ucontext_t * uc) {

  return (intptr_t*)uc->context_sp;

}

intptr_t* os::Bsd::ucontext_get_fp(const ucontext_t * uc) {

  return (intptr_t*)uc->context_fp;

}

// For Forte Analyzer AsyncGetCallTrace profiling support - thread

// is currently interrupted by SIGPROF.

// os::Solaris::fetch_frame_from_ucontext() tries to skip nested signal

// frames. Currently we don't do that on Bsd, so it's the same as

// os::fetch_frame_from_context().

// This method is also used for stack overflow signal handling.

ExtendedPC os::Bsd::fetch_frame_from_ucontext(Thread* thread,

  const ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {

  assert(thread != NULL, "just checking");

  assert(ret_sp != NULL, "just checking");

  assert(ret_fp != NULL, "just checking");

  return os::fetch_frame_from_context(uc, ret_sp, ret_fp);

}

ExtendedPC os::fetch_frame_from_context(const void* ucVoid,

                    intptr_t** ret_sp, intptr_t** ret_fp) {

  ExtendedPC  epc;

  const ucontext_t* uc = (const ucontext_t*)ucVoid;

  if (uc != NULL) {

    epc = ExtendedPC(os::Bsd::ucontext_get_pc(uc));

    if (ret_sp) *ret_sp = os::Bsd::ucontext_get_sp(uc);

    if (ret_fp) *ret_fp = os::Bsd::ucontext_get_fp(uc);

  } else {

    // construct empty ExtendedPC for return value checking

    epc = ExtendedPC(NULL);

    if (ret_sp) *ret_sp = (intptr_t *)NULL;

    if (ret_fp) *ret_fp = (intptr_t *)NULL;

  }

  return epc;

}

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

  intptr_t* sp;

  intptr_t* fp;

  ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);

  return frame(sp, fp, epc.pc());

}

frame os::fetch_frame_from_ucontext(Thread* thread, void* ucVoid) {

  intptr_t* sp;

  intptr_t* fp;

  ExtendedPC epc = os::Bsd::fetch_frame_from_ucontext(thread, (ucontext_t*)ucVoid, &sp, &fp);

  return frame(sp, fp, epc.pc());

}

bool os::Bsd::get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr) {

  address pc = (address) os::Bsd::ucontext_get_pc(uc);

  if (Interpreter::contains(pc)) {

    // interpreter performs stack banging after the fixed frame header has

    // been generated while the compilers perform it before. To maintain

    // semantic consistency between interpreted and compiled frames, the

    // method returns the Java sender of the current frame.

    *fr = os::fetch_frame_from_ucontext(thread, uc);

    if (!fr->is_first_java_frame()) {

      // get_frame_at_stack_banging_point() is only called when we

      // have well defined stacks so java_sender() calls do not need

      // to assert safe_for_sender() first.

      *fr = fr->java_sender();

    }

  } else {

    // more complex code with compiled code

    assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above");

    CodeBlob* cb = CodeCache::find_blob(pc);

    if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) {

      // Not sure where the pc points to, fallback to default

      // stack overflow handling

      return false;

    } else {

      *fr = os::fetch_frame_from_ucontext(thread, uc);

      // in compiled code, the stack banging is performed just after the return pc

      // has been pushed on the stack

      *fr = frame(fr->sp() + 1, fr->fp(), (address)*(fr->sp()));

      if (!fr->is_java_frame()) {

        // See java_sender() comment above.

        *fr = fr->java_sender();

      }

    }

  }

  assert(fr->is_java_frame(), "Safety check");

  return true;

}

// By default, gcc always save frame pointer (%ebp/%rbp) on stack. It may get

// turned off by -fomit-frame-pointer,

frame os::get_sender_for_C_frame(frame* fr) {

  return frame(fr->sender_sp(), fr->link(), fr->sender_pc());

}

intptr_t* _get_previous_fp() {

#if defined(SPARC_WORKS) || defined(__clang__) || defined(__llvm__)

  intptr_t **ebp;

  __asm__("mov %%" SPELL_REG_FP ", %0":"=r"(ebp));

#else

  register intptr_t **ebp __asm__ (SPELL_REG_FP);

#endif

  // ebp is for this frame (_get_previous_fp). We want the ebp for the

  // caller of os::current_frame*(), so go up two frames. However, for

  // optimized builds, _get_previous_fp() will be inlined, so only go

  // up 1 frame in that case.

#ifdef _NMT_NOINLINE_

  return **(intptr_t***)ebp;

#else

  return *ebp;

#endif

}

frame os::current_frame() {

  intptr_t* fp = _get_previous_fp();

  frame myframe((intptr_t*)os::current_stack_pointer(),

                (intptr_t*)fp,

                CAST_FROM_FN_PTR(address, os::current_frame));

  if (os::is_first_C_frame(&myframe)) {

    // stack is not walkable

    return frame();

  } else {

    return os::get_sender_for_C_frame(&myframe);

  }

}

// Utility functions

// From IA32 System Programming Guide

enum {

  trap_page_fault = 0xE

};

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();

  // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away

  // (no destructors can be run)

  os::ThreadCrashProtection::check_crash_protection(sig, t);

  SignalHandlerMark shm(t);

  // 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;

      }

    }

  }

/*

  NOTE: does not seem to work on bsd.

  if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {

    // can't decode this kind of signal

    info = NULL;

  } else {

    assert(sig == info->si_signo, "bad siginfo");

  }

*/

  // decide if this trap can be handled by a stub

  address stub = NULL;

  address pc          = NULL;

  //%note os_trap_1

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

    pc = (address) os::Bsd::ucontext_get_pc(uc);

    if (StubRoutines::is_safefetch_fault(pc)) {

      os::Bsd::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc));

      return 1;

    }