1 files changed, 591 insertions, 0 deletions
diff --git a/src/leveldb/util/env_boost.cc b/src/leveldb/util/env_boost.cc
new file mode 100644
index 0000000000..0190f9fb77
--- /dev/null
+++ b/src/leveldb/util/env_boost.cc
@@ -0,0 +1,591 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include <deque>
+
+#ifdef LEVELDB_PLATFORM_WINDOWS
+#include <windows.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <time.h>
+#include <io.h>
+#else
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/param.h>
+#include <time.h>
+#include <unistd.h>
+#endif
+#if defined(LEVELDB_PLATFORM_ANDROID)
+#include <sys/stat.h>
+#endif
+#include "leveldb/env.h"
+#include "leveldb/slice.h"
+
+#ifdef LEVELDB_PLATFORM_WINDOWS
+#include "util/win_logger.h"
+#else
+#include "util/posix_logger.h"
+#endif
+#include "port/port.h"
+#include "util/logging.h"
+
+#ifdef __linux
+#include <sys/sysinfo.h>
+#include <linux/unistd.h>
+#endif
+
+#include <fstream>
+
+// Boost includes - see WINDOWS file to see which modules to install
+#include <boost/date_time/gregorian/gregorian.hpp>
+#include <boost/date_time/posix_time/posix_time.hpp>
+#include <boost/filesystem/convenience.hpp>
+#include <boost/thread/once.hpp>
+#include <boost/thread/thread.hpp>
+#include <boost/bind.hpp>
+#include <boost/scoped_ptr.hpp>
+#include <boost/interprocess/sync/file_lock.hpp>
+#include <boost/thread/condition_variable.hpp>
+
+namespace leveldb {
+namespace {
+
+// returns the ID of the current process
+static boost::uint32_t current_process_id(void) {
+#ifdef _WIN32
+  return static_cast<boost::uint32_t>(::GetCurrentProcessId());
+#else
+  return static_cast<boost::uint32_t>(::getpid());
+#endif
+}
+
+// returns the ID of the current thread
+static boost::uint32_t current_thread_id(void) {
+#ifdef _WIN32
+  return static_cast<boost::uint32_t>(::GetCurrentThreadId());
+#else
+#ifdef __linux
+  return static_cast<boost::uint32_t>(::syscall(__NR_gettid));
+#else
+  // just return the pid
+  return current_process_id();
+#endif
+#endif
+}
+
+static char global_read_only_buf[0x8000];
+
+class PosixSequentialFile: public SequentialFile {
+ private:
+  std::string filename_;
+  FILE* file_;
+
+ public:
+  PosixSequentialFile(const std::string& fname, FILE* f)
+    : filename_(fname), file_(f) { }
+  virtual ~PosixSequentialFile() { fclose(file_); }
+
+  virtual Status Read(size_t n, Slice* result, char* scratch) {
+  Status s;
+#if defined(BSD) || defined(__MINGW32__)
+  // fread_unlocked doesn't exist on FreeBSD or MingW
+  size_t r = fread(scratch, 1, n, file_);
+#else
+  size_t r = fread_unlocked(scratch, 1, n, file_);
+#endif
+  *result = Slice(scratch, r);
+  if (r < n) {
+    if (feof(file_)) {
+    // We leave status as ok if we hit the end of the file
+    } else {
+    // A partial read with an error: return a non-ok status
+    s = Status::IOError(filename_, strerror(errno));
+    }
+  }
+  return s;
+  }
+
+  virtual Status Skip(uint64_t n) {
+  if (fseek(file_, n, SEEK_CUR)) {
+    return Status::IOError(filename_, strerror(errno));
+  }
+  return Status::OK();
+  }
+};
+
+class PosixRandomAccessFile: public RandomAccessFile {
+ private:
+  std::string filename_;
+  int fd_;
+  mutable boost::mutex mu_;
+
+ public:
+  PosixRandomAccessFile(const std::string& fname, int fd)
+    : filename_(fname), fd_(fd) { }
+  virtual ~PosixRandomAccessFile() { close(fd_); }
+
+  virtual Status Read(uint64_t offset, size_t n, Slice* result,
+            char* scratch) const {
+    Status s;
+#ifdef LEVELDB_PLATFORM_WINDOWS
+    // no pread on Windows so we emulate it with a mutex
+    boost::unique_lock<boost::mutex> lock(mu_);
+
+    if (::_lseeki64(fd_, offset, SEEK_SET) == -1L) {
+      return Status::IOError(filename_, strerror(errno));
+    }
+
+    int r = ::_read(fd_, scratch, n);
+    *result = Slice(scratch, (r < 0) ? 0 : r);
+    lock.unlock();
+#else
+    ssize_t r = pread(fd_, scratch, n, static_cast<off_t>(offset));
+    *result = Slice(scratch, (r < 0) ? 0 : r);
+#endif
+    if (r < 0) {
+      // An error: return a non-ok status
+      s = Status::IOError(filename_, strerror(errno));
+    }
+    return s;
+  }
+};
+
+// We preallocate up to an extra megabyte and use memcpy to append new
+// data to the file.  This is safe since we either properly close the
+// file before reading from it, or for log files, the reading code
+// knows enough to skip zero suffixes.
+
+class BoostFile : public WritableFile {
+
+public:
+  explicit BoostFile(std::string path) : path_(path), written_(0) {
+    Open();
+  }
+
+  virtual ~BoostFile() {
+    Close();
+  }
+
+private:
+  void Open() {
+    // we truncate the file as implemented in env_posix
+     file_.open(path_.generic_string().c_str(), 
+         std::ios_base::trunc | std::ios_base::out | std::ios_base::binary);
+     written_ = 0;
+  }
+
+public:
+  virtual Status Append(const Slice& data) {
+    Status result;
+    file_.write(data.data(), data.size());
+    if (!file_.good()) {
+      result = Status::IOError(
+          path_.generic_string() + " Append", "cannot write");
+    }
+    return result;
+  }
+
+  virtual Status Close() {
+    Status result;
+
+    try {
+      if (file_.is_open()) {
+        Sync();
+        file_.close();
+      }
+    } catch (const std::exception & e) {
+      result = Status::IOError(path_.generic_string() + " close", e.what());
+    }
+
+    return result;
+  }
+
+  virtual Status Flush() {
+    file_.flush();
+    return Status::OK();
+  }
+
+  virtual Status Sync() {
+    Status result;
+    try {
+      Flush();
+    } catch (const std::exception & e) {
+      result = Status::IOError(path_.string() + " sync", e.what());
+    }
+
+    return result;
+  }
+
+private:
+  boost::filesystem::path path_;
+  boost::uint64_t written_;
+  std::ofstream file_;
+};
+
+
+
+class BoostFileLock : public FileLock {
+ public:
+  boost::interprocess::file_lock fl_;
+};
+
+class PosixEnv : public Env {
+ public:
+  PosixEnv();
+  virtual ~PosixEnv() {
+    fprintf(stderr, "Destroying Env::Default()\n");
+    exit(1);
+  }
+
+  virtual Status NewSequentialFile(const std::string& fname,
+                   SequentialFile** result) {
+    FILE* f = fopen(fname.c_str(), "rb");
+    if (f == NULL) {
+      *result = NULL;
+      return Status::IOError(fname, strerror(errno));
+    } else {
+      *result = new PosixSequentialFile(fname, f);
+      return Status::OK();
+    }
+  }
+
+  virtual Status NewRandomAccessFile(const std::string& fname,
+                   RandomAccessFile** result) {
+#ifdef LEVELDB_PLATFORM_WINDOWS
+    int fd = _open(fname.c_str(), _O_RDONLY | _O_RANDOM | _O_BINARY);
+#else
+    int fd = open(fname.c_str(), O_RDONLY);
+#endif
+    if (fd < 0) {
+      *result = NULL;
+      return Status::IOError(fname, strerror(errno));
+    }
+    *result = new PosixRandomAccessFile(fname, fd);
+    return Status::OK();
+  }
+
+  virtual Status NewWritableFile(const std::string& fname,
+                 WritableFile** result) {
+    Status s;
+    try {
+      // will create a new empty file to write to
+      *result = new BoostFile(fname);
+    }
+    catch (const std::exception & e) {
+      s = Status::IOError(fname, e.what());
+    }
+
+    return s;
+  }
+
+  virtual bool FileExists(const std::string& fname) {
+    return boost::filesystem::exists(fname);
+  }
+
+  virtual Status GetChildren(const std::string& dir,
+               std::vector<std::string>* result) {
+    result->clear();
+
+    boost::system::error_code ec;
+    boost::filesystem::directory_iterator current(dir, ec);
+    if (ec != 0) {
+      return Status::IOError(dir, ec.message());
+    }
+
+    boost::filesystem::directory_iterator end;
+
+    for(; current != end; ++current) {
+      result->push_back(current->path().filename().generic_string());
+    }
+
+    return Status::OK();
+  }
+
+  virtual Status DeleteFile(const std::string& fname) {
+    boost::system::error_code ec;
+
+    boost::filesystem::remove(fname, ec);
+
+    Status result;
+
+    if (ec != 0) {
+      result = Status::IOError(fname, ec.message());
+    }
+
+    return result;
+  }
+
+  virtual Status CreateDir(const std::string& name) {
+      Status result;
+
+      if (boost::filesystem::exists(name) &&
+          boost::filesystem::is_directory(name)) {
+        return result;
+      }
+
+      boost::system::error_code ec;
+
+      if (!boost::filesystem::create_directories(name, ec)) {
+        result = Status::IOError(name, ec.message());
+      }
+
+      return result;
+    };
+
+    virtual Status DeleteDir(const std::string& name) {
+    Status result;
+
+    boost::system::error_code ec;
+    if (!boost::filesystem::remove_all(name, ec)) {
+      result = Status::IOError(name, ec.message());
+    }
+
+    return result;
+  };
+
+  virtual Status GetFileSize(const std::string& fname, uint64_t* size) {
+    boost::system::error_code ec;
+
+    Status result;
+
+    *size = static_cast<uint64_t>(boost::filesystem::file_size(fname, ec));
+    if (ec != 0) {
+      *size = 0;
+       result = Status::IOError(fname, ec.message());
+    }
+
+    return result;
+  }
+
+  virtual Status RenameFile(const std::string& src, const std::string& target) {
+    boost::system::error_code ec;
+
+    boost::filesystem::rename(src, target, ec);
+
+    Status result;
+
+    if (ec != 0) {
+      result = Status::IOError(src, ec.message());
+    }
+
+    return result;
+  }
+
+  virtual Status LockFile(const std::string& fname, FileLock** lock) {
+    *lock = NULL;
+
+    Status result;
+
+    try {
+      if (!boost::filesystem::exists(fname)) {
+        std::ofstream of(fname.c_str(), std::ios_base::trunc | std::ios_base::out);
+      }
+
+      assert(boost::filesystem::exists(fname));
+
+      boost::interprocess::file_lock fl(fname.c_str());
+      BoostFileLock * my_lock = new BoostFileLock();
+      my_lock->fl_ = std::move(fl);
+      if (!my_lock->fl_.try_lock()) {
+          return Status::IOError("database already in use: could not acquire exclusive lock");
+      }
+      *lock = my_lock;
+    } catch (const std::exception & e) {
+      result = Status::IOError("lock " + fname, e.what());
+    }
+
+    return result;
+  }
+
+  virtual Status UnlockFile(FileLock* lock) {
+
+    Status result;
+
+    try {
+      BoostFileLock * my_lock = static_cast<BoostFileLock *>(lock);
+      my_lock->fl_.unlock();
+      delete my_lock;
+    } catch (const std::exception & e) {
+      result = Status::IOError("unlock", e.what());
+    }
+
+    return result;
+  }
+
+  virtual void Schedule(void (*function)(void*), void* arg);
+
+  virtual void StartThread(void (*function)(void* arg), void* arg);
+
+  virtual Status GetTestDirectory(std::string* result) {
+    boost::system::error_code ec;
+    boost::filesystem::path temp_dir = 
+        boost::filesystem::temp_directory_path(ec);
+    if (ec != 0) {
+      temp_dir = "tmp";
+    }
+
+    temp_dir /= "leveldb_tests";
+    temp_dir /= boost::lexical_cast<std::string>(current_process_id());
+
+    // Directory may already exist
+    CreateDir(temp_dir.generic_string());
+
+    *result = temp_dir.generic_string();
+
+    return Status::OK();
+  }
+
+#ifndef LEVELDB_PLATFORM_WINDOWS
+  static uint64_t gettid() {
+    pthread_t tid = pthread_self();
+    uint64_t thread_id = 0;
+    memcpy(&thread_id, &tid, std::min(sizeof(thread_id), sizeof(tid)));
+    return thread_id;
+  }
+#endif
+
+  virtual Status NewLogger(const std::string& fname, Logger** result) {
+  FILE* f = fopen(fname.c_str(), "wt");
+  if (f == NULL) {
+    *result = NULL;
+    return Status::IOError(fname, strerror(errno));
+  } else {
+#ifdef LEVELDB_PLATFORM_WINDOWS
+    *result = new WinLogger(f);
+#else
+    *result = new PosixLogger(f, &PosixEnv::gettid);
+#endif
+    return Status::OK();
+  }
+  }
+
+  virtual uint64_t NowMicros() {
+    return static_cast<uint64_t>(
+        boost::posix_time::microsec_clock::universal_time()
+        .time_of_day().total_microseconds());
+  }
+
+  virtual void SleepForMicroseconds(int micros) {
+  boost::this_thread::sleep(boost::posix_time::microseconds(micros));
+  }
+
+ private:
+  void PthreadCall(const char* label, int result) {
+  if (result != 0) {
+    fprintf(stderr, "pthread %s: %s\n", label, strerror(result));
+    exit(1);
+  }
+  }
+
+  // BGThread() is the body of the background thread
+  void BGThread();
+
+  static void* BGThreadWrapper(void* arg) {
+    reinterpret_cast<PosixEnv*>(arg)->BGThread();
+    return NULL;
+  }
+
+  boost::mutex mu_;
+  boost::condition_variable bgsignal_;
+  boost::scoped_ptr<boost::thread> bgthread_;
+
+  // Entry per Schedule() call
+  struct BGItem { void* arg; void (*function)(void*); };
+  typedef std::deque<BGItem> BGQueue;
+  BGQueue queue_;
+};
+
+PosixEnv::PosixEnv() { }
+
+void PosixEnv::Schedule(void (*function)(void*), void* arg) {
+  boost::unique_lock<boost::mutex> lock(mu_);
+
+  // Start background thread if necessary
+  if (!bgthread_) {
+     bgthread_.reset(
+         new boost::thread(boost::bind(&PosixEnv::BGThreadWrapper, this)));
+  }
+
+  // Add to priority queue
+  queue_.push_back(BGItem());
+  queue_.back().function = function;
+  queue_.back().arg = arg;
+
+  lock.unlock();
+
+  bgsignal_.notify_one();
+
+}
+
+void PosixEnv::BGThread() {
+  while (true) {
+  // Wait until there is an item that is ready to run
+  boost::unique_lock<boost::mutex> lock(mu_);
+
+  while (queue_.empty()) {
+    bgsignal_.wait(lock);
+  }
+
+  void (*function)(void*) = queue_.front().function;
+  void* arg = queue_.front().arg;
+  queue_.pop_front();
+
+  lock.unlock();
+  (*function)(arg);
+  }
+}
+
+namespace {
+struct StartThreadState {
+  void (*user_function)(void*);
+  void* arg;
+};
+}
+
+static void* StartThreadWrapper(void* arg) {
+  StartThreadState* state = reinterpret_cast<StartThreadState*>(arg);
+  state->user_function(state->arg);
+  delete state;
+  return NULL;
+}
+
+void PosixEnv::StartThread(void (*function)(void* arg), void* arg) {
+  StartThreadState* state = new StartThreadState;
+  state->user_function = function;
+  state->arg = arg;
+
+  boost::thread t(boost::bind(&StartThreadWrapper, state));
+}
+
+}
+
+static boost::once_flag once = BOOST_ONCE_INIT;
+static Env* default_env;
+static void InitDefaultEnv() { 
+  ::memset(global_read_only_buf, 0, sizeof(global_read_only_buf));
+  default_env = new PosixEnv;
+}
+
+Env* Env::Default() {
+  boost::call_once(once, InitDefaultEnv);
+
+  return default_env;
+}
+
+}