Computer Shopper 242/Issue 242 - April 2008 - DPCS0408DVD.ISO/Software Money Savers/VirtualDub/Source/VirtualDub-1.7.7-src.7z/src/system/source/file.cpp

C/C++ Source or Header | 2007-10-13 | 18.6 KB | 766 lines

//    VirtualDub - Video processing and capture application
//    System library component
//    Copyright (C) 1998-2004 Avery Lee, All Rights Reserved.
//
//    Beginning with 1.6.0, the VirtualDub system library is licensed
//    differently than the remainder of VirtualDub.  This particular file is
//    thus licensed as follows (the "zlib" license):
//
//    This software is provided 'as-is', without any express or implied
//    warranty.  In no event will the authors be held liable for any
//    damages arising from the use of this software.
//
//    Permission is granted to anyone to use this software for any purpose,
//    including commercial applications, and to alter it and redistribute it
//    freely, subject to the following restrictions:
//
//    1.    The origin of this software must not be misrepresented; you must
//        not claim that you wrote the original software. If you use this
//        software in a product, an acknowledgment in the product
//        documentation would be appreciated but is not required.
//    2.    Altered source versions must be plainly marked as such, and must
//        not be misrepresented as being the original software.
//    3.    This notice may not be removed or altered from any source
//        distribution.

#include "stdafx.h"
#include <windows.h>

#include <vd2/system/error.h>
#include <vd2/system/filesys.h>
#include <vd2/system/VDString.h>
#include <vd2/system/file.h>

namespace {
    bool IsWindowsNT() {
        static bool sbIsNT = (LONG)GetVersion()>=0;
        return sbIsNT;
    }

    bool IsHardDrivePath(const wchar_t *path) {
        const VDStringW rootPath(VDFileGetRootPath(path));

        UINT type = GetDriveTypeW(rootPath.c_str());

        return type == DRIVE_FIXED || type == DRIVE_UNKNOWN || type == DRIVE_REMOVABLE;
    }
};

///////////////////////////////////////////////////////////////////////////////
//
//    VDFile
//
///////////////////////////////////////////////////////////////////////////////

using namespace nsVDFile;

VDFile::VDFile(const char *pszFileName, uint32 flags)
    : mhFile(NULL)
{
    open_internal(pszFileName, NULL, flags);
}

VDFile::VDFile(const wchar_t *pwszFileName, uint32 flags)
    : mhFile(NULL)
{
    open_internal(NULL, pwszFileName, flags);
}

VDFile::VDFile(HANDLE h)
    : mhFile(h)
{
    LONG lo, hi = 0;

    lo = SetFilePointer(h, 0, &hi, FILE_CURRENT);

    mFilePosition = (uint32)lo + ((uint64)(uint32)hi << 32);
}

VDFile::~VDFile() {
    closeNT();
}

void VDFile::open(const char *pszFilename, uint32 flags) {
    open_internal(pszFilename, NULL, flags);
}

void VDFile::open(const wchar_t *pwszFilename, uint32 flags) {
    open_internal(NULL, pwszFilename, flags);
}

void VDFile::open_internal(const char *pszFilename, const wchar_t *pwszFilename, uint32 flags) {
    close();

    mpFilename = _wcsdup(VDFileSplitPath(pszFilename ? VDTextAToW(pszFilename).c_str() : pwszFilename));
    if (!mpFilename)
        throw MyMemoryError();

    // At least one of the read/write flags must be set.
    VDASSERT(flags & (kRead | kWrite));

    DWORD dwDesiredAccess = 0;

    if (flags & kRead)  dwDesiredAccess  = GENERIC_READ;
    if (flags & kWrite) dwDesiredAccess |= GENERIC_WRITE;

    // Win32 docs are screwed here -- FILE_SHARE_xxx is the inverse of a deny flag.

    DWORD dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
    if (flags & kDenyRead)    dwShareMode = FILE_SHARE_WRITE;
    if (flags & kDenyWrite) dwShareMode &= ~FILE_SHARE_WRITE;

    // One of the creation flags must be set.
    VDASSERT(flags & kCreationMask);

    DWORD dwCreationDisposition;

    uint32 creationType = flags & kCreationMask;

    switch(creationType) {
    case kOpenExisting:        dwCreationDisposition = OPEN_EXISTING; break;
    case kOpenAlways:        dwCreationDisposition = OPEN_ALWAYS; break;
    case kCreateAlways:        dwCreationDisposition = CREATE_ALWAYS; break;
    case kCreateNew:        dwCreationDisposition = CREATE_NEW; break;
    case kTruncateExisting:    dwCreationDisposition = TRUNCATE_EXISTING; break;
    default:
        VDNEVERHERE;
        return;
    }

    VDASSERT((flags & (kSequential | kRandomAccess)) != (kSequential | kRandomAccess));

    DWORD dwAttributes = FILE_ATTRIBUTE_NORMAL;

    if (flags & kSequential)    dwAttributes |= FILE_FLAG_SEQUENTIAL_SCAN;
    if (flags & kRandomAccess)    dwAttributes |= FILE_FLAG_RANDOM_ACCESS;
    if (flags & kWriteThrough)    dwAttributes |= FILE_FLAG_WRITE_THROUGH;
    if (flags & kUnbuffered)    dwAttributes |= FILE_FLAG_NO_BUFFERING;

    VDStringA tempFilenameA;
    VDStringW tempFilenameW;

    if (IsWindowsNT()) {
        if (pszFilename) {
            tempFilenameW = VDTextAToW(pszFilename);
            pwszFilename = tempFilenameW.c_str();
            pszFilename = NULL;
        }
    } else {
        if (pwszFilename) {
            tempFilenameA = VDTextWToA(pwszFilename);
            pszFilename = tempFilenameA.c_str();
            pwszFilename = NULL;
        }
    }

    if (pszFilename)
        mhFile = CreateFileA(pszFilename, dwDesiredAccess, dwShareMode, NULL, dwCreationDisposition, dwAttributes, NULL);
    else {
        if (!IsHardDrivePath(pwszFilename))
            flags &= ~FILE_FLAG_NO_BUFFERING;

        mhFile = CreateFileW(pwszFilename, dwDesiredAccess, dwShareMode, NULL, dwCreationDisposition, dwAttributes, NULL);
    }

    DWORD err = GetLastError();

    // If we failed and FILE_FLAG_NO_BUFFERING was set, strip it and try again.
    // VPC and Novell shares sometimes do this....
    if (mhFile == INVALID_HANDLE_VALUE && err != ERROR_FILE_NOT_FOUND && err != ERROR_PATH_NOT_FOUND) {
        if (dwAttributes & FILE_FLAG_NO_BUFFERING) {
            dwAttributes &= ~FILE_FLAG_NO_BUFFERING;
            dwAttributes |= FILE_FLAG_WRITE_THROUGH;

            if (pszFilename)
                mhFile = CreateFileA(pszFilename, dwDesiredAccess, dwShareMode, NULL, dwCreationDisposition, dwAttributes, NULL);
            else
                mhFile = CreateFileW(pwszFilename, dwDesiredAccess, dwShareMode, NULL, dwCreationDisposition, dwAttributes, NULL);

            err = GetLastError();
        }
    }

    // INVALID_HANDLE_VALUE isn't NULL.  *sigh*

    if (mhFile == INVALID_HANDLE_VALUE) {
        mhFile = NULL;

        throw MyWin32Error("Cannot open file \"%ls\":\n%%s", err, mpFilename.get());
    }

    mFilePosition = 0;
}

bool VDFile::closeNT() {
    if (mhFile) {
        HANDLE h = mhFile;
        mhFile = NULL;
        if (!CloseHandle(h))
            return false;
    }

    return true;
}

void VDFile::close() {
    if (!closeNT())
        throw MyWin32Error("Cannot complete file \"%ls\": %%s", GetLastError(), mpFilename.get());
}

bool VDFile::truncateNT() {
    return 0 != SetEndOfFile(mhFile);
}

void VDFile::truncate() {
    if (!truncateNT())
        throw MyWin32Error("Cannot truncate file \"%ls\": %%s", GetLastError(), mpFilename.get());
}

bool VDFile::extendValidNT(sint64 pos) {
    if (GetVersion() & 0x80000000)
        return true;                // No need, Windows 95/98/ME do this automatically anyway.

    // The SetFileValidData() API is only available on XP and Server 2003.

    typedef BOOL (APIENTRY *tpSetFileValidData)(HANDLE hFile, LONGLONG ValidDataLength);        // Windows XP, Server 2003
    static tpSetFileValidData pSetFileValidData = (tpSetFileValidData)GetProcAddress(GetModuleHandle("kernel32"), "SetFileValidData");

    if (!pSetFileValidData) {
        SetLastError(ERROR_CALL_NOT_IMPLEMENTED);
        return false;
    }

    return 0 != pSetFileValidData(mhFile, pos);
}

void VDFile::extendValid(sint64 pos) {
    if (!extendValidNT(pos))
        throw MyWin32Error("Cannot extend file \"%ls\": %%s", GetLastError(), mpFilename.get());
}

bool VDFile::enableExtendValid() {
    if (GetVersion() & 0x80000000)
        return true;                // Not Windows NT, no privileges involved

    // SetFileValidData() requires the SE_MANAGE_VOLUME_NAME privilege, so we must enable it
    // on the process token. We don't attempt to strip the privilege afterward as that would
    // introduce race conditions.
    bool bSuccessful = false;
    DWORD err = 0;

    SetLastError(0);

    HANDLE h;
    if (OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES|TOKEN_QUERY, &h)) {
        LUID luid;

        if (LookupPrivilegeValue(NULL, SE_MANAGE_VOLUME_NAME, &luid)) {
            TOKEN_PRIVILEGES tp;
            tp.PrivilegeCount = 1;
            tp.Privileges[0].Luid = luid;
            tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;

            if (AdjustTokenPrivileges(h, FALSE, &tp, 0, NULL, NULL))
                bSuccessful = true;
            else
                err = GetLastError();
        }

        CloseHandle(h);
    }

    if (!bSuccessful && err)
        SetLastError(err);

    return bSuccessful;
}

long VDFile::readData(void *buffer, long length) {
    DWORD dwActual;

    if (!ReadFile(mhFile, buffer, (DWORD)length, &dwActual, NULL))
        throw MyWin32Error("Cannot read from file \"%ls\": %%s", GetLastError(), mpFilename.get());

    mFilePosition += dwActual;

    return dwActual;
}

void VDFile::read(void *buffer, long length) {
    if (length != readData(buffer, length))
        throw MyWin32Error("Cannot read from file \"%ls\": Premature end of file.", GetLastError(), mpFilename.get());
}

long VDFile::writeData(const void *buffer, long length) {
    DWORD dwActual;
    bool success = false;

    if (!WriteFile(mhFile, buffer, (DWORD)length, &dwActual, NULL) || dwActual != (DWORD)length)
        goto found_error;

    mFilePosition += dwActual;

    return dwActual;

found_error:
    throw MyWin32Error("Cannot write to file \"%ls\": %%s", GetLastError(), mpFilename.get());
}

void VDFile::write(const void *buffer, long length) {
    if (length != writeData(buffer, length))
        throw MyWin32Error("Cannot write to file \"%ls\": Unable to write all data.", GetLastError(), mpFilename.get());
}

bool VDFile::seekNT(sint64 newPos, eSeekMode mode) {
    DWORD dwMode;

    switch(mode) {
    case kSeekStart:
        dwMode = FILE_BEGIN;
        break;
    case kSeekCur:
        dwMode = FILE_CURRENT;
        break;
    case kSeekEnd:
        dwMode = FILE_END;
        break;
    default:
        VDNEVERHERE;
        return false;
    }

    union {
        sint64 pos;
        LONG l[2];
    } u = { newPos };

    u.l[0] = SetFilePointer(mhFile, u.l[0], &u.l[1], dwMode);

    if (u.l[0] == -1 && GetLastError() != NO_ERROR)
        return false;

    mFilePosition = u.pos;
    return true;
}

void VDFile::seek(sint64 newPos, eSeekMode mode) {
    if (!seekNT(newPos, mode))
        throw MyWin32Error("Cannot seek within file \"%ls\": %%s", GetLastError(), mpFilename.get());
}

bool VDFile::skipNT(sint64 delta) {
    if (!delta)
        return true;

    char buf[1024];

    if (delta <= sizeof buf) {
        return (long)delta == readData(buf, (long)delta);
    } else
        return seekNT(delta, kSeekCur);
}

void VDFile::skip(sint64 delta) {
    if (!delta)
        return;

    char buf[1024];

    if (delta <= sizeof buf) {
        if ((long)delta != readData(buf, (long)delta))
            throw MyWin32Error("Cannot seek within file \"%ls\": %%s", GetLastError(), mpFilename.get());
    } else
        seek(delta, kSeekCur);
}

sint64 VDFile::size() {
    union {
        uint64 siz;
        DWORD l[2];
    } u;

    u.l[0] = GetFileSize(mhFile, &u.l[1]);

    DWORD err;

    if (u.l[0] == (DWORD)-1L && (err = GetLastError()) != NO_ERROR)
        throw MyWin32Error("Cannot retrieve size of file \"%ls\": %%s", GetLastError(), mpFilename.get());

    return (sint64)u.siz;
}

sint64 VDFile::tell() {
    return mFilePosition;
}

bool VDFile::isOpen() {
    return mhFile != 0;
}

VDFileHandle VDFile::getRawHandle() {
    return mhFile;
}

void *VDFile::AllocUnbuffer(size_t nBytes) {
    return VirtualAlloc(NULL, nBytes, MEM_COMMIT, PAGE_READWRITE);
}

void VDFile::FreeUnbuffer(void *p) {
    VirtualFree(p, 0, MEM_RELEASE);
}

///////////////////////////////////////////////////////////////////////////////

VDFileStream::~VDFileStream() {
}

const wchar_t *VDFileStream::GetNameForError() {
    return getFilenameForError();
}

sint64 VDFileStream::Pos() {
    return tell();
}

void VDFileStream::Read(void *buffer, sint32 bytes) {
    read(buffer, bytes);
}

sint32 VDFileStream::ReadData(void *buffer, sint32 bytes) {
    return readData(buffer, bytes);
}

sint64 VDFileStream::Length() {
    return size();
}

void VDFileStream::Seek(sint64 offset) {
    seek(offset);
}

///////////////////////////////////////////////////////////////////////////////

VDMemoryStream::VDMemoryStream(const void *pSrc, uint32 len)
    : mpSrc((const char *)pSrc)
    , mPos(0)
    , mLength(len)
{
}

const wchar_t *VDMemoryStream::GetNameForError() {
    return L"memory stream";
}

sint64 VDMemoryStream::Pos() {
    return mPos;
}

void VDMemoryStream::Read(void *buffer, sint32 bytes) {
    if (bytes != ReadData(buffer, bytes))
        throw MyError("Attempt to read beyond stream.");
}

sint32 VDMemoryStream::ReadData(void *buffer, sint32 bytes) {
    if (bytes <= 0)
        return 0;

    if (bytes + mPos > mLength)
        bytes = mLength - mPos;

    if (bytes > 0) {
        memcpy(buffer, mpSrc+mPos, bytes);
        mPos += bytes;
    }

    return bytes;
}

sint64 VDMemoryStream::Length() {
    return mLength;
}

void VDMemoryStream::Seek(sint64 offset) {
    if (offset < 0 || offset > mLength)
        throw MyError("Invalid seek position");

    mPos = (uint32)offset;
}

///////////////////////////////////////////////////////////////////////////////

VDBufferedStream::VDBufferedStream(IVDRandomAccessStream *pSrc, uint32 bufferSize)
    : mpSrc(pSrc)
    , mBuffer(bufferSize)
    , mBasePosition(0)
    , mBufferOffset(0)
    , mBufferValidSize(0)
{
}

VDBufferedStream::~VDBufferedStream() {
}

const wchar_t *VDBufferedStream::GetNameForError() {
    return mpSrc->GetNameForError();
}

sint64 VDBufferedStream::Pos() {
    return mBasePosition + mBufferOffset;
}

void VDBufferedStream::Read(void *buffer, sint32 bytes) {
    if (bytes != ReadData(buffer, bytes))
        throw MyError("Cannot read %d bytes at location %08llx from %ls", mpSrc->GetNameForError());
}

sint32 VDBufferedStream::ReadData(void *buffer, sint32 bytes) {
    if (bytes <= 0)
        return 0;

    uint32 actual = 0;
    for(;;) {
        uint32 tc = mBufferValidSize - mBufferOffset;

        if (tc > (uint32)bytes)
            tc = (uint32)bytes;

        if (tc) {
            if (buffer) {
                memcpy(buffer, mBuffer.data() + mBufferOffset, tc);
                buffer = (char *)buffer + tc;
            }

            mBufferOffset += tc;
            bytes -= tc;
            actual += tc;

            if (!bytes)
                break;
        }

        // At this point, the buffer is empty.
        if (mBufferValidSize) {
            VDASSERT(mBufferOffset >= mBufferValidSize);

            mBasePosition += mBufferValidSize;
            mBufferOffset = 0;
            mBufferValidSize = 0;
        }

        // If the remaining read is large, issue it directly to the underlying stream.
        if (buffer && (uint32)bytes >= mBuffer.size() * 2) {
            sint32 localActual = mpSrc->ReadData(buffer, bytes);
            mBasePosition += localActual;
            actual += localActual;
            break;
        }

        // Refill the buffer.
        mBufferValidSize = mpSrc->ReadData(mBuffer.data(), mBuffer.size());
        mBufferOffset = 0;
        if (!mBufferValidSize)
            break;
    }

    return actual;
}

sint64 VDBufferedStream::Length() {
    return mpSrc->Length();
}

void VDBufferedStream::Seek(sint64 offset) {
    // check if an in-buffer skip is possible
    sint64 relativeOffset = offset - mBasePosition;
    if (relativeOffset >= 0 && relativeOffset <= (sint64)mBufferValidSize) {
        mBufferOffset = (uint32)relativeOffset;
        return;
    }

    // flush buffer
    mBufferOffset = 0;
    mBufferValidSize = 0;

    // issue seek
    mpSrc->Seek(offset);
    mBasePosition = offset;
}

void VDBufferedStream::Skip(sint64 size) {
    sint64 targetPos = mBasePosition + mBufferOffset + size;
    sint64 bufferEnd = mBasePosition + mBufferValidSize;

    // check if we can do a buffered skip
    if (targetPos >= bufferEnd && targetPos < bufferEnd + (sint64)mBuffer.size()) {
        Read(NULL, (sint32)size);
        return;
    }

    // issue a seek
    Seek(targetPos);
}

///////////////////////////////////////////////////////////////////////////////

VDTextStream::VDTextStream(IVDStream *pSrc)
    : mpSrc(pSrc)
    , mBufferPos(0)
    , mBufferLimit(0)
    , mState(kFetchLine)
    , mFileBuffer(kFileBufferSize)
{
}

VDTextStream::~VDTextStream() {
}

const char *VDTextStream::GetNextLine() {
    if (!mpSrc)
        return NULL;

    mLineBuffer.clear();

    for(;;) {
        if (mBufferPos >= mBufferLimit) {
            mBufferPos = 0;
            mBufferLimit = mpSrc->ReadData(mFileBuffer.data(), mFileBuffer.size());

            if (!mBufferLimit) {
                mpSrc = NULL;

                if (mLineBuffer.empty())
                    return NULL;

                mLineBuffer.push_back(0);

                return mLineBuffer.data();
            }
        }

        switch(mState) {

            case kEatNextIfCR:
                mState = kFetchLine;
                if (mFileBuffer[mBufferPos] == '\r')
                    ++mBufferPos;
                continue;

            case kEatNextIfLF:
                mState = kFetchLine;
                if (mFileBuffer[mBufferPos] == '\n')
                    ++mBufferPos;
                continue;

            case kFetchLine:
                uint32 base = mBufferPos;

                do {
                    const char c = mFileBuffer[mBufferPos++];

                    if (c == '\r') {
                        mState = kEatNextIfLF;
                        mLineBuffer.insert(mLineBuffer.end(), mFileBuffer.begin() + base, mFileBuffer.begin() + (mBufferPos-1));
                        mLineBuffer.push_back(0);
                        return mLineBuffer.data();
                    }
                    if (c == '\n') {
                        mState = kEatNextIfCR;
                        mLineBuffer.insert(mLineBuffer.end(), mFileBuffer.begin() + base, mFileBuffer.begin() + (mBufferPos-1));
                        mLineBuffer.push_back(0);
                        return mLineBuffer.data();
                    }
                } while(mBufferPos < mBufferLimit);
                mLineBuffer.insert(mLineBuffer.end(), mFileBuffer.begin() + base, mFileBuffer.begin() + mBufferLimit);
                break;
        }
    }
}

///////////////////////////////////////////////////////////////////////////////

VDTextInputFile::VDTextInputFile(const wchar_t *filename, uint32 flags)
    : mFileStream(filename, flags | nsVDFile::kRead)
    , mTextStream(&mFileStream)
{
}

VDTextInputFile::~VDTextInputFile() {
}

///////////////////////////////////////////////////////////////////////////////

VDTextOutputFile::VDTextOutputFile(const wchar_t *filename, uint32 flags)
    : mFile(filename, flags | nsVDFile::kWrite)
    , mLevel(0)
{
}

VDTextOutputFile::~VDTextOutputFile() {
    try {
        Close();
    } catch(const MyError&) {
        // ignore errors in destructor
    }
}

void VDTextOutputFile::Close() {
    if (mFile.isOpen()) {
        if (mLevel)
            mFile.write(mBuf, mLevel);
        mFile.close();
    }
}

void VDTextOutputFile::PutLine(const char *s) {
    PutData(s, strlen(s));
    PutData("\r\n", 2);
}

void VDTextOutputFile::FormatLine(const char *format, ...) {
    va_list val;

    va_start(val, format);

    int rv = -1;
    if (mLevel < kBufSize-4)
        rv = _vsnprintf(mBuf+mLevel, kBufSize-mLevel, format, val);

    if (rv >= 0)
        mLevel += rv;
    else
        FormatLine2(format, val);

    PutData("\r\n", 2);
    va_end(val);
}

void VDTextOutputFile::FormatLine2(const char *format, va_list val) {
    char buf[3072];

    int rv = _vsnprintf(buf, 3072, format, val);
    if (rv > 0)
        PutData(buf, rv);
}

void VDTextOutputFile::PutData(const char *s, int len) {
    while(len > 0) {
        int left = kBufSize - mLevel;
        if (!left) {
            mFile.write(mBuf, kBufSize);
            mLevel = 0;
            left = kBufSize;
        }

        int tc = len;

        if (tc > left)
            tc = left;

        memcpy(mBuf + mLevel, s, tc);

        s += tc;
        len -= tc;
        mLevel += tc;
    }
}