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// *****************************************************************************
// * This file is part of the FreeFileSync project. It is distributed under *
// * GNU General Public License: http://www.gnu.org/licenses/gpl-3.0 *
// * Copyright (C) Zenju (zenju AT freefilesync DOT org) - All Rights Reserved *
// *****************************************************************************
#include "file_traverser.h"
#include "file_error.h"
#ifdef ZEN_WIN
#include "int64.h"
#include "long_path_prefix.h"
#include "file_access.h"
#include "symlink_target.h"
#elif defined ZEN_MAC
#include "osx_string.h"
#endif
#if defined ZEN_LINUX || defined ZEN_MAC
#include <cstddef> //offsetof
#include <unistd.h> //::pathconf()
#include <sys/stat.h>
#include <dirent.h>
#endif
using namespace zen;
void zen::traverseFolder(const Zstring& dirPath,
const std::function<void (const FileInfo& fi)>& onFile,
const std::function<void (const DirInfo& di)>& onDir,
const std::function<void (const SymlinkInfo& si)>& onLink,
const std::function<void (const std::wstring& errorMsg)>& onError)
{
try
{
#ifdef ZEN_WIN
WIN32_FIND_DATA findData = {};
HANDLE hDir = ::FindFirstFile(applyLongPathPrefix(appendSeparator(dirPath) + L'*').c_str(), &findData);
if (hDir == INVALID_HANDLE_VALUE)
{
const DWORD ec = ::GetLastError(); //copy before directly/indirectly making other system calls!
if (ec == ERROR_FILE_NOT_FOUND)
{
//1. directory may not exist *or* 2. it is completely empty: not all directories contain "., .." entries, e.g. a drive's root directory; NetDrive
// -> FindFirstFile() is a nice example of violation of API design principle of single responsibility
if (dirExists(dirPath)) //yes, a race-condition, still the best we can do
return;
}
throw FileError(replaceCpy(_("Cannot open directory %x."), L"%x", fmtPath(dirPath)), formatSystemError(L"FindFirstFile", ec));
}
ZEN_ON_SCOPE_EXIT(::FindClose(hDir));
bool firstIteration = true;
for (;;)
{
if (firstIteration) //keep ::FindNextFile at the start of the for-loop to support "continue"!
firstIteration = false;
else if (!::FindNextFile(hDir, &findData))
{
const DWORD ec = ::GetLastError(); //copy before directly/indirectly making other system calls!
if (ec == ERROR_NO_MORE_FILES) //not an error situation
return;
//else we have a problem... report it:
throw FileError(replaceCpy(_("Cannot enumerate directory %x."), L"%x", fmtPath(dirPath)), formatSystemError(L"FindNextFile", ec));
}
//skip "." and ".."
const wchar_t* const itemNameRaw = findData.cFileName;
if (itemNameRaw[0] == L'.' &&
(itemNameRaw[1] == 0 || (itemNameRaw[1] == L'.' && itemNameRaw[2] == 0)))
continue;
if (itemNameRaw[0] == 0)
throw FileError(replaceCpy(_("Cannot enumerate directory %x."), L"%x", fmtPath(dirPath)), L"FindNextFile: Data corruption; item with empty name.");
const Zstring& itemPath = appendSeparator(dirPath) + itemNameRaw;
if (zen::isSymlink(findData)) //check first!
{
if (onLink)
onLink({ itemPath, filetimeToTimeT(findData.ftLastWriteTime) });
}
else if ((findData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0)
{
if (onDir)
onDir({ itemPath });
}
else //a file
{
if (onFile)
onFile({ itemPath, get64BitUInt(findData.nFileSizeLow, findData.nFileSizeHigh), filetimeToTimeT(findData.ftLastWriteTime) });
}
}
#elif defined ZEN_LINUX || defined ZEN_MAC
/* quote: "Since POSIX.1 does not specify the size of the d_name field, and other nonstandard fields may precede
that field within the dirent structure, portable applications that use readdir_r() should allocate
the buffer whose address is passed in entry as follows:
len = offsetof(struct dirent, d_name) + pathconf(dirPath, _PC_NAME_MAX) + 1
entryp = malloc(len); */
const size_t nameMax = std::max<long>(::pathconf(dirPath.c_str(), _PC_NAME_MAX), 10000); //::pathconf may return long(-1)
std::vector<char> buffer(offsetof(struct ::dirent, d_name) + nameMax + 1);
DIR* folder = ::opendir(dirPath.c_str()); //directory must NOT end with path separator, except "/"
if (!folder)
THROW_LAST_FILE_ERROR(replaceCpy(_("Cannot open directory %x."), L"%x", fmtPath(dirPath)), L"opendir");
ZEN_ON_SCOPE_EXIT(::closedir(folder)); //never close nullptr handles! -> crash
for (;;)
{
struct ::dirent* dirEntry = nullptr;
if (::readdir_r(folder, reinterpret_cast< ::dirent*>(&buffer[0]), &dirEntry) != 0)
THROW_LAST_FILE_ERROR(replaceCpy(_("Cannot enumerate directory %x."), L"%x", fmtPath(dirPath)), L"readdir_r");
//don't retry but restart dir traversal on error! https://blogs.msdn.microsoft.com/oldnewthing/20140612-00/?p=753/
if (!dirEntry) //no more items
return;
//don't return "." and ".."
const char* itemNameRaw = dirEntry->d_name;
if (itemNameRaw[0] == '.' &&
(itemNameRaw[1] == 0 || (itemNameRaw[1] == '.' && itemNameRaw[2] == 0)))
continue;
#ifdef ZEN_MAC //normalize all text input (see see native_traverser_impl.h)
Zstring itemName;
try
{
itemName = osx::normalizeUtfForPosix(itemNameRaw); //throw SysError
}
catch (const SysError& e) //failure is not an item-level error since we don't know the normalized name yet!!!
{
throw FileError(replaceCpy(_("Cannot enumerate directory %x."), L"%x", fmtPath(dirPath)),
L"Failed to generate normalized file name: " + fmtPath(itemNameRaw) + L"\n" + e.toString()); //too obscure to warrant translation
}
#else
const Zstring& itemName = itemNameRaw;
#endif
if (itemName.empty()) //checks result of osx::normalizeUtfForPosix, too!
throw FileError(replaceCpy(_("Cannot enumerate directory %x."), L"%x", fmtPath(dirPath)), L"readdir_r: Data corruption; item with empty name.");
const Zstring& itemPath = appendSeparator(dirPath) + itemName;
struct ::stat statData = {};
try
{
if (::lstat(itemPath.c_str(), &statData) != 0) //lstat() does not resolve symlinks
THROW_LAST_FILE_ERROR(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtPath(itemPath)), L"lstat");
}
catch (const FileError& e)
{
if (onError)
onError(e.toString());
continue; //ignore error: skip file
}
if (S_ISLNK(statData.st_mode)) //on Linux there is no distinction between file and directory symlinks!
{
if (onLink)
onLink({ itemPath, statData.st_mtime});
}
else if (S_ISDIR(statData.st_mode)) //a directory
{
if (onDir)
onDir({ itemPath });
}
else //a file or named pipe, ect.
{
if (onFile)
onFile({ itemPath, makeUnsigned(statData.st_size), statData.st_mtime });
}
/*
It may be a good idea to not check "S_ISREG(statData.st_mode)" explicitly and to not issue an error message on other types to support these scenarios:
- RTS setup watch (essentially wants to read directories only)
- removeDirectory (wants to delete everything; pipes can be deleted just like files via "unlink")
However an "open" on a pipe will block (https://sourceforge.net/p/freefilesync/bugs/221/), so the copy routines need to be smarter!!
*/
}
#endif
}
catch (const FileError& e)
{
if (onError)
onError(e.toString());
}
}
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