kun yu 77e1ddd81b branch-0.4.0
Former-commit-id: a4df63653202df32d0b983de27f5c969905d17ac
2019-07-30 10:23:34 +08:00

264 lines
7.0 KiB
C++

// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the License for the
// specific language governing permissions and limitations
// under the License.
#ifndef ARROW_UTIL_IO_UTIL_H
#define ARROW_UTIL_IO_UTIL_H
#ifndef _WIN32
#define ARROW_HAVE_SIGACTION 1
#endif
#include <memory>
#include <string>
#if ARROW_HAVE_SIGACTION
#include <signal.h> // Needed for struct sigaction
#endif
#include "arrow/io/interfaces.h"
#include "arrow/status.h"
#include "arrow/util/macros.h"
// The Windows API defines DeleteFile as a macro resolving to either
// DeleteFileA or DeleteFileW. Need to undo it.
#if defined(_WIN32) && defined(DeleteFile)
#undef DeleteFile
#endif
namespace arrow {
class Buffer;
namespace io {
// Output stream that just writes to stdout.
class ARROW_EXPORT StdoutStream : public OutputStream {
public:
StdoutStream();
~StdoutStream() override {}
Status Close() override;
bool closed() const override;
Status Tell(int64_t* position) const override;
Status Write(const void* data, int64_t nbytes) override;
private:
int64_t pos_;
};
// Output stream that just writes to stderr.
class ARROW_EXPORT StderrStream : public OutputStream {
public:
StderrStream();
~StderrStream() override {}
Status Close() override;
bool closed() const override;
Status Tell(int64_t* position) const override;
Status Write(const void* data, int64_t nbytes) override;
private:
int64_t pos_;
};
// Input stream that just reads from stdin.
class ARROW_EXPORT StdinStream : public InputStream {
public:
StdinStream();
~StdinStream() override {}
Status Close() override;
bool closed() const override;
Status Tell(int64_t* position) const override;
Status Read(int64_t nbytes, int64_t* bytes_read, void* out) override;
Status Read(int64_t nbytes, std::shared_ptr<Buffer>* out) override;
private:
int64_t pos_;
};
} // namespace io
namespace internal {
// NOTE: 8-bit path strings on Windows are encoded using UTF-8.
// Using MBCS would fail encoding some paths.
#if defined(_WIN32)
using NativePathString = std::wstring;
#else
using NativePathString = std::string;
#endif
class ARROW_EXPORT PlatformFilename {
public:
~PlatformFilename();
PlatformFilename();
PlatformFilename(const PlatformFilename&);
PlatformFilename(PlatformFilename&&);
PlatformFilename& operator=(const PlatformFilename&);
PlatformFilename& operator=(PlatformFilename&&);
explicit PlatformFilename(const NativePathString& path);
const NativePathString& ToNative() const;
std::string ToString() const;
// These functions can fail for character encoding reasons.
static Status FromString(const std::string& file_name, PlatformFilename* out);
Status Join(const std::string& child_name, PlatformFilename* out) const;
private:
struct Impl;
std::unique_ptr<Impl> impl_;
explicit PlatformFilename(const Impl& impl);
explicit PlatformFilename(Impl&& impl);
// Those functions need access to the embedded path object
friend ARROW_EXPORT Status CreateDir(const PlatformFilename&, bool*);
friend ARROW_EXPORT Status CreateDirTree(const PlatformFilename&, bool*);
friend ARROW_EXPORT Status DeleteDirTree(const PlatformFilename&, bool*);
friend ARROW_EXPORT Status DeleteFile(const PlatformFilename&, bool*);
friend ARROW_EXPORT Status FileExists(const PlatformFilename&, bool*);
};
ARROW_EXPORT
Status CreateDir(const PlatformFilename& dir_path, bool* created = NULLPTR);
ARROW_EXPORT
Status CreateDirTree(const PlatformFilename& dir_path, bool* created = NULLPTR);
ARROW_EXPORT
Status DeleteDirTree(const PlatformFilename& dir_path, bool* deleted = NULLPTR);
ARROW_EXPORT
Status DeleteFile(const PlatformFilename& file_path, bool* deleted = NULLPTR);
ARROW_EXPORT
Status FileExists(const PlatformFilename& path, bool* out);
ARROW_EXPORT
Status FileNameFromString(const std::string& file_name, PlatformFilename* out);
ARROW_EXPORT
Status FileOpenReadable(const PlatformFilename& file_name, int* fd);
ARROW_EXPORT
Status FileOpenWritable(const PlatformFilename& file_name, bool write_only, bool truncate,
bool append, int* fd);
ARROW_EXPORT
Status FileRead(int fd, uint8_t* buffer, const int64_t nbytes, int64_t* bytes_read);
ARROW_EXPORT
Status FileReadAt(int fd, uint8_t* buffer, int64_t position, int64_t nbytes,
int64_t* bytes_read);
ARROW_EXPORT
Status FileWrite(int fd, const uint8_t* buffer, const int64_t nbytes);
ARROW_EXPORT
Status FileTruncate(int fd, const int64_t size);
ARROW_EXPORT
Status FileTell(int fd, int64_t* pos);
ARROW_EXPORT
Status FileSeek(int fd, int64_t pos);
ARROW_EXPORT
Status FileSeek(int fd, int64_t pos, int whence);
ARROW_EXPORT
Status FileGetSize(int fd, int64_t* size);
ARROW_EXPORT
Status FileClose(int fd);
ARROW_EXPORT
Status CreatePipe(int fd[2]);
ARROW_EXPORT
Status MemoryMapRemap(void* addr, size_t old_size, size_t new_size, int fildes,
void** new_addr);
ARROW_EXPORT
Status GetEnvVar(const char* name, std::string* out);
ARROW_EXPORT
Status GetEnvVar(const std::string& name, std::string* out);
ARROW_EXPORT
Status SetEnvVar(const char* name, const char* value);
ARROW_EXPORT
Status SetEnvVar(const std::string& name, const std::string& value);
ARROW_EXPORT
Status DelEnvVar(const char* name);
ARROW_EXPORT
Status DelEnvVar(const std::string& name);
ARROW_EXPORT
std::string ErrnoMessage(int errnum);
#if _WIN32
ARROW_EXPORT
std::string WinErrorMessage(int errnum);
#endif
class ARROW_EXPORT TemporaryDir {
public:
~TemporaryDir();
const PlatformFilename& path() { return path_; }
static Status Make(const std::string& prefix, std::unique_ptr<TemporaryDir>* out);
private:
PlatformFilename path_;
explicit TemporaryDir(PlatformFilename&&);
};
class ARROW_EXPORT SignalHandler {
public:
typedef void (*Callback)(int);
SignalHandler();
explicit SignalHandler(Callback cb);
#if ARROW_HAVE_SIGACTION
explicit SignalHandler(const struct sigaction& sa);
#endif
Callback callback() const;
#if ARROW_HAVE_SIGACTION
const struct sigaction& action() const;
#endif
protected:
#if ARROW_HAVE_SIGACTION
// Storing the full sigaction allows to restore the entire signal handling
// configuration.
struct sigaction sa_;
#else
Callback cb_;
#endif
};
ARROW_EXPORT
Status GetSignalHandler(int signum, SignalHandler* out);
ARROW_EXPORT
Status SetSignalHandler(int signum, const SignalHandler& handler,
SignalHandler* old_handler = NULLPTR);
} // namespace internal
} // namespace arrow
#endif // ARROW_UTIL_IO_UTIL_H