From 0ea66a1275da319e2443fa1536cec7ea7fc53b53 Mon Sep 17 00:00:00 2001 From: Max Kellermann Date: Thu, 7 Aug 2014 18:10:23 +0200 Subject: fs/io/Reader: new interface --- src/fs/io/FileReader.cxx | 98 ++++++++++++++++++++++++++++++++++++++++++++++++ src/fs/io/FileReader.hxx | 67 +++++++++++++++++++++++++++++++++ src/fs/io/Reader.hxx | 51 +++++++++++++++++++++++++ 3 files changed, 216 insertions(+) create mode 100644 src/fs/io/FileReader.cxx create mode 100644 src/fs/io/FileReader.hxx create mode 100644 src/fs/io/Reader.hxx (limited to 'src/fs/io') diff --git a/src/fs/io/FileReader.cxx b/src/fs/io/FileReader.cxx new file mode 100644 index 000000000..d63cd8ab0 --- /dev/null +++ b/src/fs/io/FileReader.cxx @@ -0,0 +1,98 @@ +/* + * Copyright (C) 2003-2014 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include "config.h" +#include "FileReader.hxx" +#include "system/fd_util.h" +#include "util/Error.hxx" + +#ifdef WIN32 + +FileReader::FileReader(Path _path, Error &error) + :path(_path), + handle(CreateFile(path.c_str(), GENERIC_READ, FILE_SHARE_READ, + nullptr, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, + nullptr)) +{ + if (handle == INVALID_HANDLE_VALUE) + error.FormatLastError("Failed to open %s", path.c_str()); +} + +size_t +FileReader::Read(void *data, size_t size, Error &error) +{ + assert(IsDefined()); + + DWORD nbytes; + if (!ReadFile(handle, data, size, &nbytes, nullptr)) { + error.FormatLastError("Failed to read from %s", path.c_str()); + nbytes = 0; + } + + return nbytes; +} + +void +FileReader::Close() +{ + assert(IsDefined()); + + CloseHandle(handle); +} + +#else + +#include +#include +#include + +FileReader::FileReader(Path _path, Error &error) + :path(_path), + fd(open_cloexec(path.c_str(), + O_RDONLY, + 0)) +{ + if (fd < 0) + error.FormatErrno("Failed to open %s", path.c_str()); +} + +size_t +FileReader::Read(void *data, size_t size, Error &error) +{ + assert(IsDefined()); + + ssize_t nbytes = read(fd, data, size); + if (nbytes < 0) { + error.FormatErrno("Failed to read from %s", path.c_str()); + nbytes = 0; + } + + return nbytes; +} + +void +FileReader::Close() +{ + assert(IsDefined()); + + close(fd); + fd = -1; +} + +#endif diff --git a/src/fs/io/FileReader.hxx b/src/fs/io/FileReader.hxx new file mode 100644 index 000000000..34b43943c --- /dev/null +++ b/src/fs/io/FileReader.hxx @@ -0,0 +1,67 @@ +/* + * Copyright (C) 2003-2014 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#ifndef MPD_FILE_READER_HXX +#define MPD_FILE_READER_HXX + +#include "check.h" +#include "Reader.hxx" +#include "fs/AllocatedPath.hxx" + +#include + +#ifdef WIN32 +#include +#endif + +class Path; + +class FileReader final : public Reader { + AllocatedPath path; + +#ifdef WIN32 + HANDLE handle; +#else + int fd; +#endif + +public: + FileReader(Path _path, Error &error); + + ~FileReader() { + if (IsDefined()) + Close(); + } + + + bool IsDefined() const { +#ifdef WIN32 + return handle != INVALID_HANDLE_VALUE; +#else + return fd >= 0; +#endif + } + + void Close(); + + /* virtual methods from class Reader */ + size_t Read(void *data, size_t size, Error &error) override; +}; + +#endif diff --git a/src/fs/io/Reader.hxx b/src/fs/io/Reader.hxx new file mode 100644 index 000000000..adf7a0667 --- /dev/null +++ b/src/fs/io/Reader.hxx @@ -0,0 +1,51 @@ +/* + * Copyright (C) 2003-2014 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#ifndef MPD_READER_HXX +#define MPD_READER_HXX + +#include "check.h" +#include "Compiler.h" + +#include + +class Error; + +/** + * An interface that can read bytes from a stream until the stream + * ends. + * + * This interface is simpler and less cumbersome to use than + * #InputStream. + */ +class Reader { +public: + Reader() = default; + Reader(const Reader &) = delete; + + /** + * Read data from the stream. + * + * @return the number of bytes read into the given buffer or 0 + * on error/end-of-stream + */ + virtual size_t Read(void *data, size_t size, Error &error) = 0; +}; + +#endif -- cgit v1.2.3