// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Platform-specific code for Solaris 10 goes here. For the POSIX-compatible
// parts, the implementation is in platform-posix.cc.

#ifdef __sparc
# error "V8 does not support the SPARC CPU architecture."
#endif

#include <dlfcn.h>  // dladdr
#include <errno.h>
#include <ieeefp.h>  // finite()
#include <pthread.h>
#include <semaphore.h>
#include <signal.h>  // sigemptyset(), etc
#include <sys/mman.h>  // mmap()
#include <sys/regset.h>
#include <sys/stack.h>  // for stack alignment
#include <sys/time.h>  // gettimeofday(), timeradd()
#include <time.h>
#include <ucontext.h>  // walkstack(), getcontext()
#include <unistd.h>  // getpagesize(), usleep()

#include <cmath>

#undef MAP_TYPE

#include "src/base/macros.h"
#include "src/base/platform/platform.h"


namespace v8 {
namespace base {


const char* OS::LocalTimezone(double time, TimezoneCache* cache) {
  if (std::isnan(time)) return "";
  time_t tv = static_cast<time_t>(std::floor(time/msPerSecond));
  struct tm tm;
  struct tm* t = localtime_r(&tv, &tm);
  if (NULL == t) return "";
  return tzname[0];  // The location of the timezone string on Solaris.
}


double OS::LocalTimeOffset(TimezoneCache* cache) {
  tzset();
  return -static_cast<double>(timezone * msPerSecond);
}


void* OS::Allocate(const size_t requested,
                   size_t* allocated,
                   bool is_executable) {
  const size_t msize = RoundUp(requested, getpagesize());
  int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0);
  void* mbase = mmap(NULL, msize, prot, MAP_PRIVATE | MAP_ANON, -1, 0);

  if (mbase == MAP_FAILED) return NULL;
  *allocated = msize;
  return mbase;
}


std::vector<OS::SharedLibraryAddress> OS::GetSharedLibraryAddresses() {
  return std::vector<SharedLibraryAddress>();
}


void OS::SignalCodeMovingGC() {
}


// Constants used for mmap.
static const int kMmapFd = -1;
static const int kMmapFdOffset = 0;


VirtualMemory::VirtualMemory() : address_(NULL), size_(0) { }


VirtualMemory::VirtualMemory(size_t size)
    : address_(ReserveRegion(size)), size_(size) { }


VirtualMemory::VirtualMemory(size_t size, size_t alignment)
    : address_(NULL), size_(0) {
  DCHECK((alignment % OS::AllocateAlignment()) == 0);
  size_t request_size = RoundUp(size + alignment,
                                static_cast<intptr_t>(OS::AllocateAlignment()));
  void* reservation = mmap(OS::GetRandomMmapAddr(),
                           request_size,
                           PROT_NONE,
                           MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE,
                           kMmapFd,
                           kMmapFdOffset);
  if (reservation == MAP_FAILED) return;

  uint8_t* base = static_cast<uint8_t*>(reservation);
  uint8_t* aligned_base = RoundUp(base, alignment);
  DCHECK_LE(base, aligned_base);

  // Unmap extra memory reserved before and after the desired block.
  if (aligned_base != base) {
    size_t prefix_size = static_cast<size_t>(aligned_base - base);
    OS::Free(base, prefix_size);
    request_size -= prefix_size;
  }

  size_t aligned_size = RoundUp(size, OS::AllocateAlignment());
  DCHECK_LE(aligned_size, request_size);

  if (aligned_size != request_size) {
    size_t suffix_size = request_size - aligned_size;
    OS::Free(aligned_base + aligned_size, suffix_size);
    request_size -= suffix_size;
  }

  DCHECK(aligned_size == request_size);

  address_ = static_cast<void*>(aligned_base);
  size_ = aligned_size;
}


VirtualMemory::~VirtualMemory() {
  if (IsReserved()) {
    bool result = ReleaseRegion(address(), size());
    DCHECK(result);
    USE(result);
  }
}


bool VirtualMemory::IsReserved() {
  return address_ != NULL;
}


void VirtualMemory::Reset() {
  address_ = NULL;
  size_ = 0;
}


bool VirtualMemory::Commit(void* address, size_t size, bool is_executable) {
  return CommitRegion(address, size, is_executable);
}


bool VirtualMemory::Uncommit(void* address, size_t size) {
  return UncommitRegion(address, size);
}


bool VirtualMemory::Guard(void* address) {
  OS::Guard(address, OS::CommitPageSize());
  return true;
}


void* VirtualMemory::ReserveRegion(size_t size) {
  void* result = mmap(OS::GetRandomMmapAddr(),
                      size,
                      PROT_NONE,
                      MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE,
                      kMmapFd,
                      kMmapFdOffset);

  if (result == MAP_FAILED) return NULL;

  return result;
}


bool VirtualMemory::CommitRegion(void* base, size_t size, bool is_executable) {
  int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0);
  if (MAP_FAILED == mmap(base,
                         size,
                         prot,
                         MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED,
                         kMmapFd,
                         kMmapFdOffset)) {
    return false;
  }
  return true;
}


bool VirtualMemory::UncommitRegion(void* base, size_t size) {
  return mmap(base,
              size,
              PROT_NONE,
              MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE | MAP_FIXED,
              kMmapFd,
              kMmapFdOffset) != MAP_FAILED;
}

bool VirtualMemory::ReleasePartialRegion(void* base, size_t size,
                                         void* free_start, size_t free_size) {
  return munmap(free_start, free_size) == 0;
}

bool VirtualMemory::ReleaseRegion(void* base, size_t size) {
  return munmap(base, size) == 0;
}


bool VirtualMemory::HasLazyCommits() {
  // TODO(alph): implement for the platform.
  return false;
}

}  // namespace base
}  // namespace v8
