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|
/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
* Copyright (C) 2020, Google Inc.
*
* file.cpp - File I/O operations
*/
#include "libcamera/internal/file.h"
#include <errno.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include "libcamera/internal/log.h"
/**
* \file file.h
* \brief File I/O operations
*/
namespace libcamera {
LOG_DEFINE_CATEGORY(File);
/**
* \class File
* \brief Interface for I/O operations on files
*
* The File class provides an interface to perform I/O operations on files. It
* wraps opening, closing and mapping files in memory, and handles the cleaning
* of allocated resources.
*
* File instances are usually constructed with a file name, but the name can be
* set later through the setFileName() function. Instances are not automatically
* opened when constructed, and shall be opened explictly with open().
*
* Files can be mapped to the process memory with map(). Mapped regions can be
* unmapped manually with munmap(), and are automatically unmapped when the File
* is destroyed or when it is used to reference another file with setFileName().
*/
/**
* \enum File::MapFlag
* \brief Flags for the File::map() function
* \var File::MapNoOption
* \brief No option (used as default value)
* \var File::MapPrivate
* \brief The memory region is mapped as private, changes are not reflected in
* the file constents
*/
/**
* \enum File::OpenMode
* \brief Mode in which a file is opened
* \var File::NotOpen
* \brief The file is not open
* \var File::ReadOnly
* \brief The file is open for reading
* \var File::WriteOnly
* \brief The file is open for writing
* \var File::ReadWrite
* \brief The file is open for reading and writing
*/
/**
* \brief Construct a File to represent the file \a name
* \param[in] name The file name
*
* Upon construction the File object is closed and shall be opened with open()
* before performing I/O operations.
*/
File::File(const std::string &name)
: name_(name), fd_(-1), mode_(NotOpen), error_(0)
{
}
/**
* \brief Construct a File without an associated name
*
* Before being used for any purpose, the file name shall be set with
* setFileName().
*/
File::File()
: fd_(-1), mode_(NotOpen), error_(0)
{
}
/**
* \brief Destroy a File instance
*
* Any memory mapping associated with the File is unmapped, and the File is
* closed if it is open.
*/
File::~File()
{
unmapAll();
close();
}
/**
* \fn const std::string &File::fileName() const
* \brief Retrieve the file name
* \return The file name
*/
/**
* \brief Set the name of the file
|
