FileUtils.cpp

/*
 * Copyright(c) Sophist Solutions, Inc. 1990-2026.  All rights reserved
 */
#include "Stroika/Foundation/StroikaPreComp.h"
 
#include <cstdio>
#include <ctime>
#include <fcntl.h>
#include <fstream>
#include <limits>
#include <sys/stat.h>
#include <sys/types.h>
 
#if qStroika_Foundation_Common_Platform_Windows
#include <aclapi.h>
#include <io.h>
#include <shlobj.h>
#include <windows.h>
#elif qStroika_Foundation_Common_Platform_POSIX
#include <unistd.h>
#endif
 
#include "Stroika/Foundation/Characters/Format.h"
#include "Stroika/Foundation/Containers/Set.h"
#include "Stroika/Foundation/Execution/Exceptions.h"
#include "Stroika/Foundation/Execution/Throw.h"
#if qStroika_Foundation_Common_Platform_Windows
#include "Stroika/Foundation/Execution/Platform/Windows/Exception.h"
#include "Stroika/Foundation/Execution/Platform/Windows/HRESULTErrorException.h"
#endif
#include "Stroika/Foundation/Containers/Common.h"
#include "Stroika/Foundation/Debug/Trace.h"
#include "Stroika/Foundation/IO/FileSystem/Exception.h"
#include "Stroika/Foundation/IO/FileSystem/FileSystem.h"
#include "Stroika/Foundation/IO/FileSystem/PathName.h"
#include "Stroika/Foundation/IO/FileSystem/WellKnownLocations.h"
 
#include "FileUtils.h"
 
using namespace Stroika::Foundation;
using namespace Stroika::Foundation::Characters;
using namespace Stroika::Foundation::Containers;
using namespace Stroika::Foundation::Execution;
using namespace Stroika::Foundation::IO;
using namespace Stroika::Foundation::IO::FileSystem;
using namespace Stroika::Foundation::Memory;
 
#if qStroika_Foundation_Common_Platform_Windows
using Execution::Platform::Windows::ThrowIfZeroGetLastError;
#endif
 
/*
 ********************************************************************************
 ******************* FileSystem::FileSizeToDisplayString ************************
 ********************************************************************************
 */
String IO::FileSystem::FileSizeToDisplayString (FileOffset_t bytes)
{
    if (bytes < 1000) {
        return Format ("{} bytes"_f, static_cast<int> (bytes));
    }
    else if (bytes < 1000 * 1024) {
        return Format ("%{:.1} K"_f, static_cast<double> (bytes) / 1024.0f);
    }
    else {
        return Format ("{:.1} MB"_f, static_cast<double> (bytes) / (1024 * 1024.0f));
    }
}
 
/*
 ********************************************************************************
 ************************ FileSystem::SetFileAccessWideOpened *******************
 ********************************************************************************
 */
/*
 * Sets permissions for users on a given folder to full control
 *
 *      Add 'Everyone' to have FULL ACCESS to the given argument file
 *
 */
void IO::FileSystem::SetFileAccessWideOpened (const filesystem::path& filePathName)
{
#if qStroika_Foundation_Common_Platform_Windows
    static PACL pACL = nullptr; // Don't bother with ::LocalFree (pACL); - since we cache keeping this guy around for speed
    if (pACL == nullptr) {
        PSID pSIDEveryone = nullptr;
 
        {
            // Specify the DACL to use.
            // Create a SID for the Everyone group.
            SID_IDENTIFIER_AUTHORITY SIDAuthWorld = SECURITY_WORLD_SID_AUTHORITY;
            if (!::AllocateAndInitializeSid (&SIDAuthWorld, 1, SECURITY_WORLD_RID, 0, 0, 0, 0, 0, 0, 0, &pSIDEveryone)) {
                return; // if this fails - perhaps old OS with no security - just fail silently...
            }
        }
 
        EXPLICIT_ACCESS ea[1]{};
        // Set FULL access for Everyone.
        ea[0].grfAccessPermissions = GENERIC_ALL;
        ea[0].grfAccessMode        = SET_ACCESS;
        ea[0].grfInheritance       = SUB_CONTAINERS_AND_OBJECTS_INHERIT;
        ea[0].Trustee.TrusteeForm  = TRUSTEE_IS_SID;
        ea[0].Trustee.TrusteeType  = TRUSTEE_IS_WELL_KNOWN_GROUP;
        ea[0].Trustee.ptstrName    = (LPTSTR)pSIDEveryone;
 
        if (ERROR_SUCCESS != ::SetEntriesInAcl (static_cast<DWORD> (std::size (ea)), ea, nullptr, &pACL)) {
            ::FreeSid (pSIDEveryone);
            return; // silently ignore errors - probably just old OS etc....
        }
        ::FreeSid (pSIDEveryone);
    }
 
    // Try to modify the object's DACL.
    [[maybe_unused]] DWORD dwRes = ::SetNamedSecurityInfo (const_cast<SDKChar*> (filePathName.c_str ()), // name of the object
                                                           SE_FILE_OBJECT,                               // type of object
                                                           DACL_SECURITY_INFORMATION,                    // change only the object's DACL
                                                           nullptr, nullptr,                             // don't change owner or group
                                                           pACL,                                         // DACL specified
                                                           nullptr);                                     // don't change SACL
    // ignore error from this routine for now  - probably means either we don't have permissions or OS too old to support...
#elif qStroika_Foundation_Common_Platform_POSIX
    ////TODO: Somewhat PRIMITIVE - TMPHACK
    if (filePathName.empty ()) [[unlikely]] {
        Execution::Throw (Exception{make_error_code (errc::no_such_file_or_directory), L"bad filename"_k});
    }
    struct stat s;
    IO::FileSystem::Exception::ThrowPOSIXErrNoIfNegative (::stat (filePathName.generic_string ().c_str (), &s), filePathName);
 
    mode_t desiredMode = (S_IRUSR | S_IRGRP | S_IROTH) | (S_IWUSR | S_IWGRP | S_IWOTH);
    if (S_ISDIR (s.st_mode)) {
        desiredMode |= (S_IXUSR | S_IXGRP | S_IXOTH);
    }
 
    int result = 0;
    // Don't call chmod if mode is already open (because doing so could fail even though we already have what we wnat if were not the owner)
    if ((s.st_mode & desiredMode) != desiredMode) {
        result = ::chmod (filePathName.generic_string ().c_str (), desiredMode);
    }
    IO::FileSystem::Exception::ThrowPOSIXErrNoIfNegative (result, filePathName);
#else
    AssertNotImplemented ();
#endif
}
 
#if qStroika_Foundation_Common_Platform_Windows
/*
 ********************************************************************************
 ********************** FileSystem::is_cygwin_symlink ***************************
 ********************************************************************************
 */
bool FileSystem::is_cygwin_symlink (const filesystem::path& p)
{
    if (filesystem::exists (p)) {
        DWORD attributes = GetFileAttributes (p.native ().c_str ());
        if (attributes & FILE_ATTRIBUTE_SYSTEM) [[unlikely]] {
            try {
                (void)read_cygwin_symlink (p);
                return true; // else would throw
            }
            catch (...) {
                return false;
            }
        }
    }
    return false;
}
 
/*
 ********************************************************************************
 ********************** FileSystem::read_cygwin_symlink *************************
 ********************************************************************************
 */
filesystem::path FileSystem::read_cygwin_symlink (const filesystem::path& p)
{
    if (filesystem::exists (p)) [[likely]] {
        DWORD attributes = GetFileAttributes (p.native ().c_str ());
        if (attributes & FILE_ATTRIBUTE_SYSTEM) [[likely]] {
            ifstream file{p, ios::binary};
            if (file.is_open ()) [[likely]] {
                char buffer[MAX_PATH + 11];
                file.read (buffer, sizeof (buffer));
                size_t         nBytesRead    = static_cast<size_t> (file.gcount ());
                constexpr auto kMagicHeader_ = "!<symlink>"sv;
                if (nBytesRead > 10 and strncmp (buffer, kMagicHeader_.data (), 10) == 0) [[likely]] {
                    return &buffer[kMagicHeader_.size ()];
                }
            }
        }
    }
    Execution::Throw (filesystem_error{"read_cygwin_symlink", p, make_error_code (errc::wrong_protocol_type)}); // not sure best error to throw?
}
#endif
 
/*
 ********************************************************************************
 ************************** FileSystem::GetVolumeName ***************************
 ********************************************************************************
 */
String IO::FileSystem::GetVolumeName (const filesystem::path& driveLetterAbsPath)
{
#if qStroika_Foundation_Common_Platform_Windows
    // SEM_FAILCRITICALERRORS needed to avoid dialog in call to GetVolumeInformation
    AdjustSysErrorMode errorModeAdjuster (AdjustSysErrorMode::GetErrorMode () | SEM_NOOPENFILEERRORBOX | SEM_FAILCRITICALERRORS);
 
    DWORD ignored = 0;
    SDKChar volNameBuf[1024]{}; // zero init cuz docs (https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getvolumeinformationa) - not clear on behavior so assume worst
    SDKChar igBuf[1024];        // dont zero initialize cuz ignored
    BOOL    result = ::GetVolumeInformation (driveLetterAbsPath.c_str (), volNameBuf, static_cast<DWORD> (std::size (volNameBuf)), nullptr,
                                             &ignored, &ignored, igBuf, static_cast<DWORD> (std::size (igBuf)));
    if (result) {
        return String::FromSDKString (volNameBuf);
    }
#else
    AssertNotImplemented ();
#endif
    return String{};
}
 
/*
 ********************************************************************************
 ******************************* FileSystem::CopyFile ***************************
 ********************************************************************************
 */
void IO::FileSystem::CopyFile (const filesystem::path& srcFile, const filesystem::path& destPath)
{
#if qStroika_Foundation_Common_Platform_Windows
    // see if can be/should be rewritten to use Win32 API of same name!!!
    //
    // If I DON'T do that remapping to Win32 API, then redo this at least to copy / rename through tmpfile
    IO::FileSystem::Default ().CheckAccess (srcFile, IO::AccessMode::eRead);
    create_directories (destPath.parent_path ());
    ThrowIfZeroGetLastError (::CopyFile (destPath.c_str (), srcFile.c_str (), false));
#else
    AssertNotImplemented ();
#endif
}
 
/*
 ********************************************************************************
 ***************************** FileSystem::FindFiles ****************************
 ********************************************************************************
 */
vector<String> IO::FileSystem::FindFiles (const filesystem::path& path, const String& fileNameToMatch)
{
    vector<String> result;
    if (path.empty ()) {
        return result;
    }
#if qStroika_Foundation_Common_Platform_Windows
    String          usePath       = AssureDirectoryPathSlashTerminated (String{path});
    String          matchFullPath = usePath + (fileNameToMatch.empty () ? L"*" : fileNameToMatch);
    WIN32_FIND_DATA fd{};
    HANDLE          hFind = ::FindFirstFile (matchFullPath.AsSDKString ().c_str (), &fd);
    if (hFind != INVALID_HANDLE_VALUE) {
        try {
            do {
                String fileName = String::FromSDKString (fd.cFileName);
                if (not(fd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)) {
                    result.push_back (usePath + fileName);
                }
            } while (::FindNextFile (hFind, &fd));
        }
        catch (...) {
            ::FindClose (hFind);
            Execution::ReThrow ();
        }
        ::FindClose (hFind);
    }
#else
    AssertNotImplemented ();
#endif
    return result;
}
 
/*
 ********************************************************************************
 ************************* FileSystem::FindFilesOneDirUnder *********************
 ********************************************************************************
 */
vector<String> IO::FileSystem::FindFilesOneDirUnder (const filesystem::path& path, const String& fileNameToMatch)
{
    if (path.empty ()) {
        return vector<String> ();
    }
 
    Containers::Set<String> resultSet;
#if qStroika_Foundation_Common_Platform_Windows
    String          usePath = AssureDirectoryPathSlashTerminated (String{path});
    WIN32_FIND_DATA fd{};
    HANDLE          hFind = ::FindFirstFile ((usePath + "*"sv).AsSDKString ().c_str (), &fd);
    if (hFind != INVALID_HANDLE_VALUE) {
        do {
            //SDKString fileName = (LPCTSTR)&fd.cFileName;
            if (fd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
                String              fileName = String::FromSDKString (static_cast<LPCTSTR> (fd.cFileName));
                static const String kDOT     = "."sv;
                static const String kDOTDOT  = ".."sv;
                if ((fileName != kDOT) and (fileName != kDOTDOT)) {
                    resultSet += Containers::Set<String> (FindFiles (usePath.As<filesystem::path> () / fileName.As<filesystem::path> (), fileNameToMatch));
                }
            }
        } while (::FindNextFile (hFind, &fd));
        ::FindClose (hFind);
    }
#else
    AssertNotImplemented ();
#endif
    return vector<String>{resultSet.begin (), Iterator<String>{resultSet.end ()}};
}
 
#if qStroika_Foundation_Common_Platform_Windows
/*
 ********************************************************************************
 ********************* FileSystem::DirectoryChangeWatcher ***********************
 ********************************************************************************
 */
IO::FileSystem::DirectoryChangeWatcher::DirectoryChangeWatcher (const filesystem::path& directoryName, bool watchSubTree, DWORD notifyFilter)
    : fDirectory{directoryName}
    , fWatchSubTree{watchSubTree}
    , fDoneEvent{::CreateEvent (nullptr, false, false, nullptr)}
    , fWatchEvent{::FindFirstChangeNotification (fDirectory.AsSDKString ().c_str (), fWatchSubTree, notifyFilter)}
    , fQuitting{false}
{
    fThread = Execution::Thread::New ([this] () { ThreadProc (this); }, Execution::Thread::eAutoStart, "DirectoryChangeWatcher"sv);
}
 
IO::FileSystem::DirectoryChangeWatcher::~DirectoryChangeWatcher ()
{
    fQuitting = true;
    if (fDoneEvent != INVALID_HANDLE_VALUE) {
        Verify (::SetEvent (fDoneEvent));
    }
    // critical we wait for finish of thread cuz it has bare 'this' pointer captured
    Thread::SuppressInterruptionInContext suppressInterruption;
    IgnoreExceptionsForCall (fThread.AbortAndWaitForDone ());
    if (fDoneEvent != INVALID_HANDLE_VALUE) {
        Verify (::CloseHandle (fDoneEvent));
    }
    if (fWatchEvent != INVALID_HANDLE_VALUE) {
        Verify (::FindCloseChangeNotification (fWatchEvent));
    }
}
 
void IO::FileSystem::DirectoryChangeWatcher::ValueChanged ()
{
}
 
void IO::FileSystem::DirectoryChangeWatcher::ThreadProc (void* lpParameter)
{
    DirectoryChangeWatcher* _THS_ = reinterpret_cast<DirectoryChangeWatcher*> (lpParameter);
    while (not _THS_->fQuitting and _THS_->fWatchEvent != INVALID_HANDLE_VALUE) {
        HANDLE events[2];
        events[0] = _THS_->fDoneEvent;
        events[1] = _THS_->fWatchEvent;
        ::WaitForMultipleObjects (static_cast<DWORD> (std::size (events)), events, false, INFINITE);
        Verify (::FindNextChangeNotification (_THS_->fWatchEvent));
        if (not _THS_->fQuitting) {
            _THS_->ValueChanged ();
        }
    }
}
#endif
 
#if qStroika_Foundation_Common_Platform_Windows
/*
 ********************************************************************************
 ********************** FileSystem::AdjustSysErrorMode **************************
 ********************************************************************************
 */
UINT AdjustSysErrorMode::GetErrorMode ()
{
    UINT good = ::SetErrorMode (0);
    ::SetErrorMode (good);
    return good;
}
 
AdjustSysErrorMode::AdjustSysErrorMode (UINT newErrorMode)
    : fSavedErrorMode{::SetErrorMode (newErrorMode)}
{
}
 
AdjustSysErrorMode::~AdjustSysErrorMode ()
{
    (void)::SetErrorMode (fSavedErrorMode);
}
#endif