• 1. 关键词
• 2. fileutil.h
• 3. fileutil.cpp
• 4. filesystem_win.h
• 5. filesystem_win.cpp
• 6. filesystem_unix.cpp
• 7. 源码地址

1. 关键词

C++ 文件系统操作 列出指定目录下的所有文件 列出指定目录下的所有文件夹 跨平台

2. fileutil.h

<code>

#pragma once

#include <string>

#include <cstdio>

#include <cstdint>

#include "filetype.h"

#include "filepath.h"

namespace cutl

{

/**

* @brief The file guard class to manage the FILE pointer automatically.

* file_guard object can close the FILE pointer automatically when his scope is exit.

*/

class file_guard

{

public:

/**

* @brief Construct a new file guard object

*

* @param file the pointer of the FILE object

*/

explicit file_guard(FILE *file);

/**

* @brief Destroy the file guard object

*

*/

~file_guard();

/**

* @brief Get the FILE pointer.

*

* @return FILE*

*/

FILE *getfd() const;

private:

FILE *file_;

};

/**

* @brief List all files in a directory.

*

* @param dirpath the filepath of the directory to be listed

* @param type file type to be listed, default is all types.

* @param recursive whether to list the whole directory recursively, default is false.

* If true, means list the whole directory recursively, like the 'ls -R' command.

* @return filevec the vector of file_entity, filepaths in the directory.

*/

filevec list_files(const filepath &dirpath, filetype type = filetype::all, bool recursive = false);

} // namespace cutl

3. fileutil.cpp

#include <cstdio>

#include <map>

#include <iostream>

#include <cstring>

#include <sys/stat.h>

#include "fileutil.h"

#include "inner/logger.h"

#include "inner/filesystem.h"

#include "strutil.h"

namespace cutl

{

file_guard::file_guard(FILE *file)

: file_(file)

{

}

file_guard::~file_guard()

{

if (file_)

{

// CUTL_DEBUG("close file");

int ret = fclose(file_);

if (ret != 0)

{

CUTL_ERROR("fail to close file, ret" + std::to_string(ret));

}

file_ = nullptr;

}

// ROBOLOG_DCHECK(file_ == nullptr);

}

FILE *file_guard::getfd() const

{

return file_;

}

filevec list_files(const filepath &dirpath, filetype type, bool recursive)

{

return list_sub_files(dirpath.str(), type, recursive);

}

4. filesystem_win.h

#include <vector>

#include <string>

#pragma once

namespace cutl

{

filetype get_file_type(const std::string &filepath);

filevec list_sub_files(const std::string &dirpath, filetype type = filetype::all, bool recursive = false);

} // namespace cutl

5. filesystem_win.cpp

#if defined(_WIN32) || defined(__WIN32__)

#include <io.h>

#include <direct.h>

#include <Windows.h>

#include <stdlib.h>

#include "strutil.h"

#include "filesystem.h"

#include "logger.h"

namespace cutl

{

filetype get_file_type(DWORD attributes, const std::string &extension)

{

filetype type = filetype::unknown;

if (attributes == INVALID_FILE_ATTRIBUTES)

{

CUTL_WARN("Failed to get file attributes, error code: " + std::to_string(GetLastError()));

if (extension == ".lnk")

{

// 注意：测试时发现，有些快捷方式访问会失败，用后缀名判断进行兜底

type = filetype::symlink;

}

return type;

}

else

{

if (attributes & FILE_ATTRIBUTE_DIRECTORY)

{

type = filetype::directory; // directory

}

else if (attributes & FILE_ATTRIBUTE_NORMAL || attributes & FILE_ATTRIBUTE_READONLY)

{

// 普通文件|只读文件

type = filetype::file; // regular file

}

else if ((attributes & FILE_ATTRIBUTE_ARCHIVE) && extension == ".lnk")

{

// windows的快捷方式

type = filetype::symlink; // symbolic link

}

}

return type;

}

std::string get_file_extension(const std::string &filepath)

{

auto pos = filepath.find_last_of('.');

std::string extension = "";

if (pos != std::string::npos)

{

extension = filepath.substr(pos);

extension = cutl::to_lower(extension);

}

return extension;

}

// https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getfileattributesa

// https://learn.microsoft.com/en-us/windows/win32/fileio/file-attribute-constants

filetype get_file_type(const std::string &filepath)

{

auto attributes = GetFileAttributesA(filepath.c_str());

auto extension = get_file_extension(filepath);

// CUTL_DEBUG(filepath + ", extension: " + extension + ", attributes: " + std::to_string(attributes));

return get_file_type(attributes, extension);

}

filevec list_sub_files(const std::string &dirpath, filetype type, bool recursive)

{

filevec file_list;

// 使用FindFirstFileA查找第一个文件

auto findpath = dirpath + win_separator + "*.*";

WIN32_FIND_DATAA findData = {0};

HANDLE hFind = FindFirstFileA(findpath.c_str(), &findData);

if (hFind == INVALID_HANDLE_VALUE || hFind == NULL)

{

CUTL_ERROR("FindFirstFileA failed for " + findpath + ", errCode: " + std::to_string(GetLastError()));

return file_list;

}

do

{

auto dwAttrs = findData.dwFileAttributes;

auto filename = std::string(findData.cFileName);

CUTL_DEBUG(filename + ", attributes: " + std::to_string(dwAttrs));

if (is_special_dir(filename))

{

// “..”和“.”不做处理

continue;

}

std::string filepath = dirpath + win_separator + filename;

auto extension = get_file_extension(filename);

auto ftype = get_file_type(dwAttrs, extension);

if (ftype & type)

{

file_entity entity;

entity.type = ftype;

entity.filepath = filepath;

file_list.emplace_back(entity);

}

if ((dwAttrs & FILE_ATTRIBUTE_DIRECTORY) && recursive)

{

// directory

auto sub_files = list_sub_files(filepath, type, recursive);

if (!sub_files.empty())

{

file_list.insert(file_list.end(), sub_files.begin(), sub_files.end());

}

}

} while (FindNextFileA(hFind, &findData));

// 关闭句柄

FindClose(hFind);

return file_list;

}

} // namespace cutl

#endif // defined(_WIN32) || defined(__WIN32__)

6. filesystem_unix.cpp

#if defined(_WIN32) || defined(__WIN32__)

// do nothing

#else

#include <unistd.h>

#include <sys/stat.h>

#include <dirent.h>

#include <stack>

#include <cstring>

#include <utime.h>

#include <stdlib.h>

#include <sys/time.h>

#include "filesystem.h"

#include "inner/logger.h"

namespace cutl

{

filetype get_file_type(const std::string &filepath)

{

struct stat file_stat;

int ret = lstat(filepath.c_str(), &file_stat);

if (0 != ret)

{

CUTL_ERROR("stat error. filepath:" + filepath + ", error:" + strerror(errno));

return filetype::unknown;

}

return get_file_type(file_stat.st_mode);

}

filevec list_sub_files(const std::string &dirpath, filetype type, bool recursive)

{

filevec file_list;

DIR *dir = opendir(dirpath.c_str()); // 打开这个目录

if (dir == NULL)

{

CUTL_ERROR("opendir error. dirpath:" + dirpath + ", error:" + strerror(errno));

return file_list;

}

struct dirent *file_info = NULL;

// 逐个读取目录中的文件到file_info

while ((file_info = readdir(dir)) != NULL)

{

// 系统有个系统文件，名为“..”和“.”,对它不做处理

std::string filename(file_info->d_name);

if (is_special_dir(filename))

{

continue;

}

struct stat file_stat; // 文件的信息

std::string filepath = dirpath + unix_separator + filename;

int ret = lstat(filepath.c_str(), &file_stat);

if (0 != ret)

{

CUTL_ERROR("stat error. filepath:" + filepath + ", error:" + strerror(errno));

closedir(dir);

return file_list;

}

auto ftype = get_file_type(file_stat.st_mode);

if (ftype & type)

{

file_entity entity;

entity.type = ftype;

entity.filepath = filepath;

file_list.emplace_back(entity);

}

if (S_ISDIR(file_stat.st_mode) && recursive)

{

auto sub_files = list_sub_files(filepath, type, recursive);

if (!sub_files.empty())

{

file_list.insert(file_list.end(), sub_files.begin(), sub_files.end());

}

}

}

closedir(dir);

return file_list;

}

} // namespace cutl

#endif // defined(_WIN32) || defined(__WIN32__)

7. 源码地址

更多详细代码，请查看本人写的C++ 通用工具库: common_util, 本项目已开源，代码简洁，且有详细的文档和Demo。

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