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-rw-r--r--src/leveldb/port/README10
-rw-r--r--src/leveldb/port/atomic_pointer.h223
-rw-r--r--src/leveldb/port/port.h21
-rw-r--r--src/leveldb/port/port_example.h135
-rw-r--r--src/leveldb/port/port_posix.cc54
-rw-r--r--src/leveldb/port/port_posix.h158
-rw-r--r--src/leveldb/port/port_win.cc147
-rw-r--r--src/leveldb/port/port_win.h174
-rw-r--r--src/leveldb/port/thread_annotations.h60
-rw-r--r--src/leveldb/port/win/stdint.h24
10 files changed, 1006 insertions, 0 deletions
diff --git a/src/leveldb/port/README b/src/leveldb/port/README
new file mode 100644
index 0000000000..422563e25c
--- /dev/null
+++ b/src/leveldb/port/README
@@ -0,0 +1,10 @@
+This directory contains interfaces and implementations that isolate the
+rest of the package from platform details.
+
+Code in the rest of the package includes "port.h" from this directory.
+"port.h" in turn includes a platform specific "port_<platform>.h" file
+that provides the platform specific implementation.
+
+See port_posix.h for an example of what must be provided in a platform
+specific header file.
+
diff --git a/src/leveldb/port/atomic_pointer.h b/src/leveldb/port/atomic_pointer.h
new file mode 100644
index 0000000000..9bf091f757
--- /dev/null
+++ b/src/leveldb/port/atomic_pointer.h
@@ -0,0 +1,223 @@
+// 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.
+
+// AtomicPointer provides storage for a lock-free pointer.
+// Platform-dependent implementation of AtomicPointer:
+// - If the platform provides a cheap barrier, we use it with raw pointers
+// - If <atomic> is present (on newer versions of gcc, it is), we use
+// a <atomic>-based AtomicPointer. However we prefer the memory
+// barrier based version, because at least on a gcc 4.4 32-bit build
+// on linux, we have encountered a buggy <atomic> implementation.
+// Also, some <atomic> implementations are much slower than a memory-barrier
+// based implementation (~16ns for <atomic> based acquire-load vs. ~1ns for
+// a barrier based acquire-load).
+// This code is based on atomicops-internals-* in Google's perftools:
+// http://code.google.com/p/google-perftools/source/browse/#svn%2Ftrunk%2Fsrc%2Fbase
+
+#ifndef PORT_ATOMIC_POINTER_H_
+#define PORT_ATOMIC_POINTER_H_
+
+#include <stdint.h>
+#ifdef LEVELDB_ATOMIC_PRESENT
+#include <atomic>
+#endif
+#ifdef OS_WIN
+#include <windows.h>
+#endif
+#ifdef OS_MACOSX
+#include <libkern/OSAtomic.h>
+#endif
+
+#if defined(_M_X64) || defined(__x86_64__)
+#define ARCH_CPU_X86_FAMILY 1
+#elif defined(_M_IX86) || defined(__i386__) || defined(__i386)
+#define ARCH_CPU_X86_FAMILY 1
+#elif defined(__ARMEL__)
+#define ARCH_CPU_ARM_FAMILY 1
+#elif defined(__ppc__) || defined(__powerpc__) || defined(__powerpc64__)
+#define ARCH_CPU_PPC_FAMILY 1
+#endif
+
+namespace leveldb {
+namespace port {
+
+// Define MemoryBarrier() if available
+// Windows on x86
+#if defined(OS_WIN) && defined(COMPILER_MSVC) && defined(ARCH_CPU_X86_FAMILY)
+// windows.h already provides a MemoryBarrier(void) macro
+// http://msdn.microsoft.com/en-us/library/ms684208(v=vs.85).aspx
+#define LEVELDB_HAVE_MEMORY_BARRIER
+
+// Mac OS
+#elif defined(OS_MACOSX)
+inline void MemoryBarrier() {
+ OSMemoryBarrier();
+}
+#define LEVELDB_HAVE_MEMORY_BARRIER
+
+// Gcc on x86
+#elif defined(ARCH_CPU_X86_FAMILY) && defined(__GNUC__)
+inline void MemoryBarrier() {
+ // See http://gcc.gnu.org/ml/gcc/2003-04/msg01180.html for a discussion on
+ // this idiom. Also see http://en.wikipedia.org/wiki/Memory_ordering.
+ __asm__ __volatile__("" : : : "memory");
+}
+#define LEVELDB_HAVE_MEMORY_BARRIER
+
+// Sun Studio
+#elif defined(ARCH_CPU_X86_FAMILY) && defined(__SUNPRO_CC)
+inline void MemoryBarrier() {
+ // See http://gcc.gnu.org/ml/gcc/2003-04/msg01180.html for a discussion on
+ // this idiom. Also see http://en.wikipedia.org/wiki/Memory_ordering.
+ asm volatile("" : : : "memory");
+}
+#define LEVELDB_HAVE_MEMORY_BARRIER
+
+// ARM Linux
+#elif defined(ARCH_CPU_ARM_FAMILY) && defined(__linux__)
+typedef void (*LinuxKernelMemoryBarrierFunc)(void);
+// The Linux ARM kernel provides a highly optimized device-specific memory
+// barrier function at a fixed memory address that is mapped in every
+// user-level process.
+//
+// This beats using CPU-specific instructions which are, on single-core
+// devices, un-necessary and very costly (e.g. ARMv7-A "dmb" takes more
+// than 180ns on a Cortex-A8 like the one on a Nexus One). Benchmarking
+// shows that the extra function call cost is completely negligible on
+// multi-core devices.
+//
+inline void MemoryBarrier() {
+ (*(LinuxKernelMemoryBarrierFunc)0xffff0fa0)();
+}
+#define LEVELDB_HAVE_MEMORY_BARRIER
+
+// PPC
+#elif defined(ARCH_CPU_PPC_FAMILY) && defined(__GNUC__)
+inline void MemoryBarrier() {
+ // TODO for some powerpc expert: is there a cheaper suitable variant?
+ // Perhaps by having separate barriers for acquire and release ops.
+ asm volatile("sync" : : : "memory");
+}
+#define LEVELDB_HAVE_MEMORY_BARRIER
+
+#endif
+
+// AtomicPointer built using platform-specific MemoryBarrier()
+#if defined(LEVELDB_HAVE_MEMORY_BARRIER)
+class AtomicPointer {
+ private:
+ void* rep_;
+ public:
+ AtomicPointer() { }
+ explicit AtomicPointer(void* p) : rep_(p) {}
+ inline void* NoBarrier_Load() const { return rep_; }
+ inline void NoBarrier_Store(void* v) { rep_ = v; }
+ inline void* Acquire_Load() const {
+ void* result = rep_;
+ MemoryBarrier();
+ return result;
+ }
+ inline void Release_Store(void* v) {
+ MemoryBarrier();
+ rep_ = v;
+ }
+};
+
+// AtomicPointer based on <cstdatomic>
+#elif defined(LEVELDB_ATOMIC_PRESENT)
+class AtomicPointer {
+ private:
+ std::atomic<void*> rep_;
+ public:
+ AtomicPointer() { }
+ explicit AtomicPointer(void* v) : rep_(v) { }
+ inline void* Acquire_Load() const {
+ return rep_.load(std::memory_order_acquire);
+ }
+ inline void Release_Store(void* v) {
+ rep_.store(v, std::memory_order_release);
+ }
+ inline void* NoBarrier_Load() const {
+ return rep_.load(std::memory_order_relaxed);
+ }
+ inline void NoBarrier_Store(void* v) {
+ rep_.store(v, std::memory_order_relaxed);
+ }
+};
+
+// Atomic pointer based on sparc memory barriers
+#elif defined(__sparcv9) && defined(__GNUC__)
+class AtomicPointer {
+ private:
+ void* rep_;
+ public:
+ AtomicPointer() { }
+ explicit AtomicPointer(void* v) : rep_(v) { }
+ inline void* Acquire_Load() const {
+ void* val;
+ __asm__ __volatile__ (
+ "ldx [%[rep_]], %[val] \n\t"
+ "membar #LoadLoad|#LoadStore \n\t"
+ : [val] "=r" (val)
+ : [rep_] "r" (&rep_)
+ : "memory");
+ return val;
+ }
+ inline void Release_Store(void* v) {
+ __asm__ __volatile__ (
+ "membar #LoadStore|#StoreStore \n\t"
+ "stx %[v], [%[rep_]] \n\t"
+ :
+ : [rep_] "r" (&rep_), [v] "r" (v)
+ : "memory");
+ }
+ inline void* NoBarrier_Load() const { return rep_; }
+ inline void NoBarrier_Store(void* v) { rep_ = v; }
+};
+
+// Atomic pointer based on ia64 acq/rel
+#elif defined(__ia64) && defined(__GNUC__)
+class AtomicPointer {
+ private:
+ void* rep_;
+ public:
+ AtomicPointer() { }
+ explicit AtomicPointer(void* v) : rep_(v) { }
+ inline void* Acquire_Load() const {
+ void* val ;
+ __asm__ __volatile__ (
+ "ld8.acq %[val] = [%[rep_]] \n\t"
+ : [val] "=r" (val)
+ : [rep_] "r" (&rep_)
+ : "memory"
+ );
+ return val;
+ }
+ inline void Release_Store(void* v) {
+ __asm__ __volatile__ (
+ "st8.rel [%[rep_]] = %[v] \n\t"
+ :
+ : [rep_] "r" (&rep_), [v] "r" (v)
+ : "memory"
+ );
+ }
+ inline void* NoBarrier_Load() const { return rep_; }
+ inline void NoBarrier_Store(void* v) { rep_ = v; }
+};
+
+// We have neither MemoryBarrier(), nor <atomic>
+#else
+#error Please implement AtomicPointer for this platform.
+
+#endif
+
+#undef LEVELDB_HAVE_MEMORY_BARRIER
+#undef ARCH_CPU_X86_FAMILY
+#undef ARCH_CPU_ARM_FAMILY
+#undef ARCH_CPU_PPC_FAMILY
+
+} // namespace port
+} // namespace leveldb
+
+#endif // PORT_ATOMIC_POINTER_H_
diff --git a/src/leveldb/port/port.h b/src/leveldb/port/port.h
new file mode 100644
index 0000000000..4baafa8e22
--- /dev/null
+++ b/src/leveldb/port/port.h
@@ -0,0 +1,21 @@
+// 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.
+
+#ifndef STORAGE_LEVELDB_PORT_PORT_H_
+#define STORAGE_LEVELDB_PORT_PORT_H_
+
+#include <string.h>
+
+// Include the appropriate platform specific file below. If you are
+// porting to a new platform, see "port_example.h" for documentation
+// of what the new port_<platform>.h file must provide.
+#if defined(LEVELDB_PLATFORM_POSIX)
+# include "port/port_posix.h"
+#elif defined(LEVELDB_PLATFORM_CHROMIUM)
+# include "port/port_chromium.h"
+#elif defined(LEVELDB_PLATFORM_WINDOWS)
+# include "port/port_win.h"
+#endif
+
+#endif // STORAGE_LEVELDB_PORT_PORT_H_
diff --git a/src/leveldb/port/port_example.h b/src/leveldb/port/port_example.h
new file mode 100644
index 0000000000..ab9e489b32
--- /dev/null
+++ b/src/leveldb/port/port_example.h
@@ -0,0 +1,135 @@
+// 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.
+//
+// This file contains the specification, but not the implementations,
+// of the types/operations/etc. that should be defined by a platform
+// specific port_<platform>.h file. Use this file as a reference for
+// how to port this package to a new platform.
+
+#ifndef STORAGE_LEVELDB_PORT_PORT_EXAMPLE_H_
+#define STORAGE_LEVELDB_PORT_PORT_EXAMPLE_H_
+
+namespace leveldb {
+namespace port {
+
+// TODO(jorlow): Many of these belong more in the environment class rather than
+// here. We should try moving them and see if it affects perf.
+
+// The following boolean constant must be true on a little-endian machine
+// and false otherwise.
+static const bool kLittleEndian = true /* or some other expression */;
+
+// ------------------ Threading -------------------
+
+// A Mutex represents an exclusive lock.
+class Mutex {
+ public:
+ Mutex();
+ ~Mutex();
+
+ // Lock the mutex. Waits until other lockers have exited.
+ // Will deadlock if the mutex is already locked by this thread.
+ void Lock();
+
+ // Unlock the mutex.
+ // REQUIRES: This mutex was locked by this thread.
+ void Unlock();
+
+ // Optionally crash if this thread does not hold this mutex.
+ // The implementation must be fast, especially if NDEBUG is
+ // defined. The implementation is allowed to skip all checks.
+ void AssertHeld();
+};
+
+class CondVar {
+ public:
+ explicit CondVar(Mutex* mu);
+ ~CondVar();
+
+ // Atomically release *mu and block on this condition variable until
+ // either a call to SignalAll(), or a call to Signal() that picks
+ // this thread to wakeup.
+ // REQUIRES: this thread holds *mu
+ void Wait();
+
+ // If there are some threads waiting, wake up at least one of them.
+ void Signal();
+
+ // Wake up all waiting threads.
+ void SignallAll();
+};
+
+// Thread-safe initialization.
+// Used as follows:
+// static port::OnceType init_control = LEVELDB_ONCE_INIT;
+// static void Initializer() { ... do something ...; }
+// ...
+// port::InitOnce(&init_control, &Initializer);
+typedef intptr_t OnceType;
+#define LEVELDB_ONCE_INIT 0
+extern void InitOnce(port::OnceType*, void (*initializer)());
+
+// A type that holds a pointer that can be read or written atomically
+// (i.e., without word-tearing.)
+class AtomicPointer {
+ private:
+ intptr_t rep_;
+ public:
+ // Initialize to arbitrary value
+ AtomicPointer();
+
+ // Initialize to hold v
+ explicit AtomicPointer(void* v) : rep_(v) { }
+
+ // Read and return the stored pointer with the guarantee that no
+ // later memory access (read or write) by this thread can be
+ // reordered ahead of this read.
+ void* Acquire_Load() const;
+
+ // Set v as the stored pointer with the guarantee that no earlier
+ // memory access (read or write) by this thread can be reordered
+ // after this store.
+ void Release_Store(void* v);
+
+ // Read the stored pointer with no ordering guarantees.
+ void* NoBarrier_Load() const;
+
+ // Set va as the stored pointer with no ordering guarantees.
+ void NoBarrier_Store(void* v);
+};
+
+// ------------------ Compression -------------------
+
+// Store the snappy compression of "input[0,input_length-1]" in *output.
+// Returns false if snappy is not supported by this port.
+extern bool Snappy_Compress(const char* input, size_t input_length,
+ std::string* output);
+
+// If input[0,input_length-1] looks like a valid snappy compressed
+// buffer, store the size of the uncompressed data in *result and
+// return true. Else return false.
+extern bool Snappy_GetUncompressedLength(const char* input, size_t length,
+ size_t* result);
+
+// Attempt to snappy uncompress input[0,input_length-1] into *output.
+// Returns true if successful, false if the input is invalid lightweight
+// compressed data.
+//
+// REQUIRES: at least the first "n" bytes of output[] must be writable
+// where "n" is the result of a successful call to
+// Snappy_GetUncompressedLength.
+extern bool Snappy_Uncompress(const char* input_data, size_t input_length,
+ char* output);
+
+// ------------------ Miscellaneous -------------------
+
+// If heap profiling is not supported, returns false.
+// Else repeatedly calls (*func)(arg, data, n) and then returns true.
+// The concatenation of all "data[0,n-1]" fragments is the heap profile.
+extern bool GetHeapProfile(void (*func)(void*, const char*, int), void* arg);
+
+} // namespace port
+} // namespace leveldb
+
+#endif // STORAGE_LEVELDB_PORT_PORT_EXAMPLE_H_
diff --git a/src/leveldb/port/port_posix.cc b/src/leveldb/port/port_posix.cc
new file mode 100644
index 0000000000..5ba127a5b9
--- /dev/null
+++ b/src/leveldb/port/port_posix.cc
@@ -0,0 +1,54 @@
+// 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 "port/port_posix.h"
+
+#include <cstdlib>
+#include <stdio.h>
+#include <string.h>
+#include "util/logging.h"
+
+namespace leveldb {
+namespace port {
+
+static void PthreadCall(const char* label, int result) {
+ if (result != 0) {
+ fprintf(stderr, "pthread %s: %s\n", label, strerror(result));
+ abort();
+ }
+}
+
+Mutex::Mutex() { PthreadCall("init mutex", pthread_mutex_init(&mu_, NULL)); }
+
+Mutex::~Mutex() { PthreadCall("destroy mutex", pthread_mutex_destroy(&mu_)); }
+
+void Mutex::Lock() { PthreadCall("lock", pthread_mutex_lock(&mu_)); }
+
+void Mutex::Unlock() { PthreadCall("unlock", pthread_mutex_unlock(&mu_)); }
+
+CondVar::CondVar(Mutex* mu)
+ : mu_(mu) {
+ PthreadCall("init cv", pthread_cond_init(&cv_, NULL));
+}
+
+CondVar::~CondVar() { PthreadCall("destroy cv", pthread_cond_destroy(&cv_)); }
+
+void CondVar::Wait() {
+ PthreadCall("wait", pthread_cond_wait(&cv_, &mu_->mu_));
+}
+
+void CondVar::Signal() {
+ PthreadCall("signal", pthread_cond_signal(&cv_));
+}
+
+void CondVar::SignalAll() {
+ PthreadCall("broadcast", pthread_cond_broadcast(&cv_));
+}
+
+void InitOnce(OnceType* once, void (*initializer)()) {
+ PthreadCall("once", pthread_once(once, initializer));
+}
+
+} // namespace port
+} // namespace leveldb
diff --git a/src/leveldb/port/port_posix.h b/src/leveldb/port/port_posix.h
new file mode 100644
index 0000000000..ccca9939d3
--- /dev/null
+++ b/src/leveldb/port/port_posix.h
@@ -0,0 +1,158 @@
+// 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.
+//
+// See port_example.h for documentation for the following types/functions.
+
+#ifndef STORAGE_LEVELDB_PORT_PORT_POSIX_H_
+#define STORAGE_LEVELDB_PORT_PORT_POSIX_H_
+
+#undef PLATFORM_IS_LITTLE_ENDIAN
+#if defined(OS_MACOSX)
+ #include <machine/endian.h>
+ #if defined(__DARWIN_LITTLE_ENDIAN) && defined(__DARWIN_BYTE_ORDER)
+ #define PLATFORM_IS_LITTLE_ENDIAN \
+ (__DARWIN_BYTE_ORDER == __DARWIN_LITTLE_ENDIAN)
+ #endif
+#elif defined(OS_SOLARIS)
+ #include <sys/isa_defs.h>
+ #ifdef _LITTLE_ENDIAN
+ #define PLATFORM_IS_LITTLE_ENDIAN true
+ #else
+ #define PLATFORM_IS_LITTLE_ENDIAN false
+ #endif
+#elif defined(OS_FREEBSD) || defined(OS_OPENBSD) ||\
+ defined(OS_NETBSD) || defined(OS_DRAGONFLYBSD)
+ #include <sys/types.h>
+ #include <sys/endian.h>
+ #define PLATFORM_IS_LITTLE_ENDIAN (_BYTE_ORDER == _LITTLE_ENDIAN)
+#elif defined(OS_HPUX)
+ #define PLATFORM_IS_LITTLE_ENDIAN false
+#elif defined(OS_ANDROID)
+ // Due to a bug in the NDK x86 <sys/endian.h> definition,
+ // _BYTE_ORDER must be used instead of __BYTE_ORDER on Android.
+ // See http://code.google.com/p/android/issues/detail?id=39824
+ #include <endian.h>
+ #define PLATFORM_IS_LITTLE_ENDIAN (_BYTE_ORDER == _LITTLE_ENDIAN)
+#else
+ #include <endian.h>
+#endif
+
+#include <pthread.h>
+#ifdef SNAPPY
+#include <snappy.h>
+#endif
+#include <stdint.h>
+#include <string>
+#include "port/atomic_pointer.h"
+
+#ifndef PLATFORM_IS_LITTLE_ENDIAN
+#define PLATFORM_IS_LITTLE_ENDIAN (__BYTE_ORDER == __LITTLE_ENDIAN)
+#endif
+
+#if defined(OS_MACOSX) || defined(OS_SOLARIS) || defined(OS_FREEBSD) ||\
+ defined(OS_NETBSD) || defined(OS_OPENBSD) || defined(OS_DRAGONFLYBSD) ||\
+ defined(OS_ANDROID) || defined(OS_HPUX) || defined(CYGWIN)
+// Use fread/fwrite/fflush on platforms without _unlocked variants
+#define fread_unlocked fread
+#define fwrite_unlocked fwrite
+#define fflush_unlocked fflush
+#endif
+
+#if defined(OS_FREEBSD) ||\
+ defined(OS_OPENBSD) || defined(OS_DRAGONFLYBSD)
+// Use fsync() on platforms without fdatasync()
+#define fdatasync fsync
+#endif
+
+#if defined(OS_MACOSX)
+#define fdatasync(fd) fcntl(fd, F_FULLFSYNC, 0)
+#endif
+
+#if defined(OS_ANDROID) && __ANDROID_API__ < 9
+// fdatasync() was only introduced in API level 9 on Android. Use fsync()
+// when targetting older platforms.
+#define fdatasync fsync
+#endif
+
+namespace leveldb {
+namespace port {
+
+static const bool kLittleEndian = PLATFORM_IS_LITTLE_ENDIAN;
+#undef PLATFORM_IS_LITTLE_ENDIAN
+
+class CondVar;
+
+class Mutex {
+ public:
+ Mutex();
+ ~Mutex();
+
+ void Lock();
+ void Unlock();
+ void AssertHeld() { }
+
+ private:
+ friend class CondVar;
+ pthread_mutex_t mu_;
+
+ // No copying
+ Mutex(const Mutex&);
+ void operator=(const Mutex&);
+};
+
+class CondVar {
+ public:
+ explicit CondVar(Mutex* mu);
+ ~CondVar();
+ void Wait();
+ void Signal();
+ void SignalAll();
+ private:
+ pthread_cond_t cv_;
+ Mutex* mu_;
+};
+
+typedef pthread_once_t OnceType;
+#define LEVELDB_ONCE_INIT PTHREAD_ONCE_INIT
+extern void InitOnce(OnceType* once, void (*initializer)());
+
+inline bool Snappy_Compress(const char* input, size_t length,
+ ::std::string* output) {
+#ifdef SNAPPY
+ output->resize(snappy::MaxCompressedLength(length));
+ size_t outlen;
+ snappy::RawCompress(input, length, &(*output)[0], &outlen);
+ output->resize(outlen);
+ return true;
+#endif
+
+ return false;
+}
+
+inline bool Snappy_GetUncompressedLength(const char* input, size_t length,
+ size_t* result) {
+#ifdef SNAPPY
+ return snappy::GetUncompressedLength(input, length, result);
+#else
+ return false;
+#endif
+}
+
+inline bool Snappy_Uncompress(const char* input, size_t length,
+ char* output) {
+#ifdef SNAPPY
+ return snappy::RawUncompress(input, length, output);
+#else
+ return false;
+#endif
+}
+
+inline bool GetHeapProfile(void (*func)(void*, const char*, int), void* arg) {
+ return false;
+}
+
+} // namespace port
+} // namespace leveldb
+
+#endif // STORAGE_LEVELDB_PORT_PORT_POSIX_H_
diff --git a/src/leveldb/port/port_win.cc b/src/leveldb/port/port_win.cc
new file mode 100644
index 0000000000..1b0f060a19
--- /dev/null
+++ b/src/leveldb/port/port_win.cc
@@ -0,0 +1,147 @@
+// LevelDB 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.
+//
+// See port_example.h for documentation for the following types/functions.
+
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the distribution.
+// * Neither the name of the University of California, Berkeley nor the
+// names of its contributors may be used to endorse or promote products
+// derived from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
+// DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+
+#include "port/port_win.h"
+
+#include <windows.h>
+#include <cassert>
+
+namespace leveldb {
+namespace port {
+
+Mutex::Mutex() :
+ cs_(NULL) {
+ assert(!cs_);
+ cs_ = static_cast<void *>(new CRITICAL_SECTION());
+ ::InitializeCriticalSection(static_cast<CRITICAL_SECTION *>(cs_));
+ assert(cs_);
+}
+
+Mutex::~Mutex() {
+ assert(cs_);
+ ::DeleteCriticalSection(static_cast<CRITICAL_SECTION *>(cs_));
+ delete static_cast<CRITICAL_SECTION *>(cs_);
+ cs_ = NULL;
+ assert(!cs_);
+}
+
+void Mutex::Lock() {
+ assert(cs_);
+ ::EnterCriticalSection(static_cast<CRITICAL_SECTION *>(cs_));
+}
+
+void Mutex::Unlock() {
+ assert(cs_);
+ ::LeaveCriticalSection(static_cast<CRITICAL_SECTION *>(cs_));
+}
+
+void Mutex::AssertHeld() {
+ assert(cs_);
+ assert(1);
+}
+
+CondVar::CondVar(Mutex* mu) :
+ waiting_(0),
+ mu_(mu),
+ sem1_(::CreateSemaphore(NULL, 0, 10000, NULL)),
+ sem2_(::CreateSemaphore(NULL, 0, 10000, NULL)) {
+ assert(mu_);
+}
+
+CondVar::~CondVar() {
+ ::CloseHandle(sem1_);
+ ::CloseHandle(sem2_);
+}
+
+void CondVar::Wait() {
+ mu_->AssertHeld();
+
+ wait_mtx_.Lock();
+ ++waiting_;
+ wait_mtx_.Unlock();
+
+ mu_->Unlock();
+
+ // initiate handshake
+ ::WaitForSingleObject(sem1_, INFINITE);
+ ::ReleaseSemaphore(sem2_, 1, NULL);
+ mu_->Lock();
+}
+
+void CondVar::Signal() {
+ wait_mtx_.Lock();
+ if (waiting_ > 0) {
+ --waiting_;
+
+ // finalize handshake
+ ::ReleaseSemaphore(sem1_, 1, NULL);
+ ::WaitForSingleObject(sem2_, INFINITE);
+ }
+ wait_mtx_.Unlock();
+}
+
+void CondVar::SignalAll() {
+ wait_mtx_.Lock();
+ ::ReleaseSemaphore(sem1_, waiting_, NULL);
+ while(waiting_ > 0) {
+ --waiting_;
+ ::WaitForSingleObject(sem2_, INFINITE);
+ }
+ wait_mtx_.Unlock();
+}
+
+AtomicPointer::AtomicPointer(void* v) {
+ Release_Store(v);
+}
+
+void InitOnce(OnceType* once, void (*initializer)()) {
+ once->InitOnce(initializer);
+}
+
+void* AtomicPointer::Acquire_Load() const {
+ void * p = NULL;
+ InterlockedExchangePointer(&p, rep_);
+ return p;
+}
+
+void AtomicPointer::Release_Store(void* v) {
+ InterlockedExchangePointer(&rep_, v);
+}
+
+void* AtomicPointer::NoBarrier_Load() const {
+ return rep_;
+}
+
+void AtomicPointer::NoBarrier_Store(void* v) {
+ rep_ = v;
+}
+
+}
+}
diff --git a/src/leveldb/port/port_win.h b/src/leveldb/port/port_win.h
new file mode 100644
index 0000000000..45bf2f0ea7
--- /dev/null
+++ b/src/leveldb/port/port_win.h
@@ -0,0 +1,174 @@
+// LevelDB 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.
+//
+// See port_example.h for documentation for the following types/functions.
+
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the distribution.
+// * Neither the name of the University of California, Berkeley nor the
+// names of its contributors may be used to endorse or promote products
+// derived from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
+// DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+
+#ifndef STORAGE_LEVELDB_PORT_PORT_WIN_H_
+#define STORAGE_LEVELDB_PORT_PORT_WIN_H_
+
+#ifdef _MSC_VER
+#define snprintf _snprintf
+#define close _close
+#define fread_unlocked _fread_nolock
+#endif
+
+#include <string>
+#include <stdint.h>
+#ifdef SNAPPY
+#include <snappy.h>
+#endif
+
+namespace leveldb {
+namespace port {
+
+// Windows is little endian (for now :p)
+static const bool kLittleEndian = true;
+
+class CondVar;
+
+class Mutex {
+ public:
+ Mutex();
+ ~Mutex();
+
+ void Lock();
+ void Unlock();
+ void AssertHeld();
+
+ private:
+ friend class CondVar;
+ // critical sections are more efficient than mutexes
+ // but they are not recursive and can only be used to synchronize threads within the same process
+ // we use opaque void * to avoid including windows.h in port_win.h
+ void * cs_;
+
+ // No copying
+ Mutex(const Mutex&);
+ void operator=(const Mutex&);
+};
+
+// the Win32 API offers a dependable condition variable mechanism, but only starting with
+// Windows 2008 and Vista
+// no matter what we will implement our own condition variable with a semaphore
+// implementation as described in a paper written by Andrew D. Birrell in 2003
+class CondVar {
+ public:
+ explicit CondVar(Mutex* mu);
+ ~CondVar();
+ void Wait();
+ void Signal();
+ void SignalAll();
+ private:
+ Mutex* mu_;
+
+ Mutex wait_mtx_;
+ long waiting_;
+
+ void * sem1_;
+ void * sem2_;
+
+
+};
+
+class OnceType {
+public:
+// OnceType() : init_(false) {}
+ OnceType(const OnceType &once) : init_(once.init_) {}
+ OnceType(bool f) : init_(f) {}
+ void InitOnce(void (*initializer)()) {
+ mutex_.Lock();
+ if (!init_) {
+ init_ = true;
+ initializer();
+ }
+ mutex_.Unlock();
+ }
+
+private:
+ bool init_;
+ Mutex mutex_;
+};
+
+#define LEVELDB_ONCE_INIT false
+extern void InitOnce(port::OnceType*, void (*initializer)());
+
+// Storage for a lock-free pointer
+class AtomicPointer {
+ private:
+ void * rep_;
+ public:
+ AtomicPointer() : rep_(NULL) { }
+ explicit AtomicPointer(void* v);
+ void* Acquire_Load() const;
+
+ void Release_Store(void* v);
+
+ void* NoBarrier_Load() const;
+
+ void NoBarrier_Store(void* v);
+};
+
+inline bool Snappy_Compress(const char* input, size_t length,
+ ::std::string* output) {
+#ifdef SNAPPY
+ output->resize(snappy::MaxCompressedLength(length));
+ size_t outlen;
+ snappy::RawCompress(input, length, &(*output)[0], &outlen);
+ output->resize(outlen);
+ return true;
+#endif
+
+ return false;
+}
+
+inline bool Snappy_GetUncompressedLength(const char* input, size_t length,
+ size_t* result) {
+#ifdef SNAPPY
+ return snappy::GetUncompressedLength(input, length, result);
+#else
+ return false;
+#endif
+}
+
+inline bool Snappy_Uncompress(const char* input, size_t length,
+ char* output) {
+#ifdef SNAPPY
+ return snappy::RawUncompress(input, length, output);
+#else
+ return false;
+#endif
+}
+
+inline bool GetHeapProfile(void (*func)(void*, const char*, int), void* arg) {
+ return false;
+}
+
+}
+}
+
+#endif // STORAGE_LEVELDB_PORT_PORT_WIN_H_
diff --git a/src/leveldb/port/thread_annotations.h b/src/leveldb/port/thread_annotations.h
new file mode 100644
index 0000000000..9470ef587c
--- /dev/null
+++ b/src/leveldb/port/thread_annotations.h
@@ -0,0 +1,60 @@
+// Copyright (c) 2012 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.
+
+#ifndef STORAGE_LEVELDB_PORT_THREAD_ANNOTATIONS_H_
+#define STORAGE_LEVELDB_PORT_THREAD_ANNOTATIONS_H_
+
+// Some environments provide custom macros to aid in static thread-safety
+// analysis. Provide empty definitions of such macros unless they are already
+// defined.
+
+#ifndef EXCLUSIVE_LOCKS_REQUIRED
+#define EXCLUSIVE_LOCKS_REQUIRED(...)
+#endif
+
+#ifndef SHARED_LOCKS_REQUIRED
+#define SHARED_LOCKS_REQUIRED(...)
+#endif
+
+#ifndef LOCKS_EXCLUDED
+#define LOCKS_EXCLUDED(...)
+#endif
+
+#ifndef LOCK_RETURNED
+#define LOCK_RETURNED(x)
+#endif
+
+#ifndef LOCKABLE
+#define LOCKABLE
+#endif
+
+#ifndef SCOPED_LOCKABLE
+#define SCOPED_LOCKABLE
+#endif
+
+#ifndef EXCLUSIVE_LOCK_FUNCTION
+#define EXCLUSIVE_LOCK_FUNCTION(...)
+#endif
+
+#ifndef SHARED_LOCK_FUNCTION
+#define SHARED_LOCK_FUNCTION(...)
+#endif
+
+#ifndef EXCLUSIVE_TRYLOCK_FUNCTION
+#define EXCLUSIVE_TRYLOCK_FUNCTION(...)
+#endif
+
+#ifndef SHARED_TRYLOCK_FUNCTION
+#define SHARED_TRYLOCK_FUNCTION(...)
+#endif
+
+#ifndef UNLOCK_FUNCTION
+#define UNLOCK_FUNCTION(...)
+#endif
+
+#ifndef NO_THREAD_SAFETY_ANALYSIS
+#define NO_THREAD_SAFETY_ANALYSIS
+#endif
+
+#endif // STORAGE_LEVELDB_PORT_THREAD_ANNOTATIONS_H_
diff --git a/src/leveldb/port/win/stdint.h b/src/leveldb/port/win/stdint.h
new file mode 100644
index 0000000000..39edd0db13
--- /dev/null
+++ b/src/leveldb/port/win/stdint.h
@@ -0,0 +1,24 @@
+// 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.
+
+// MSVC didn't ship with this file until the 2010 version.
+
+#ifndef STORAGE_LEVELDB_PORT_WIN_STDINT_H_
+#define STORAGE_LEVELDB_PORT_WIN_STDINT_H_
+
+#if !defined(_MSC_VER)
+#error This file should only be included when compiling with MSVC.
+#endif
+
+// Define C99 equivalent types.
+typedef signed char int8_t;
+typedef signed short int16_t;
+typedef signed int int32_t;
+typedef signed long long int64_t;
+typedef unsigned char uint8_t;
+typedef unsigned short uint16_t;
+typedef unsigned int uint32_t;
+typedef unsigned long long uint64_t;
+
+#endif // STORAGE_LEVELDB_PORT_WIN_STDINT_H_
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-17 12:50:29 +0000