C++文件系统操作5 - 跨平台列出指定目录下的所有文件和文件夹
- 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
#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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