/* $Id: GuestCtrlIO.cpp 39843 2012-01-23 18:38:18Z vboxsync $ */
/** @file
 *
 * IO helper for IGuest COM class implementations.
 */

/*
 * Copyright (C) 2011 Oracle Corporation
 *
 * This file is part of VirtualBox Open Source Edition (OSE), as
 * available from http://www.virtualbox.org. This file is free software;
 * you can redistribute it and/or modify it under the terms of the GNU
 * General Public License (GPL) as published by the Free Software
 * Foundation, in version 2 as it comes in the "COPYING" file of the
 * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
 * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
 */

/******************************************************************************
 *   Header Files                                                             *
 ******************************************************************************/
#include "GuestCtrlImplPrivate.h"
#ifdef DEBUG
# include "Logging.h"
# include <iprt/file.h>
#endif /* DEBUG */

/******************************************************************************
 *   Structures and Typedefs                                                  *
 ******************************************************************************/

/** @todo *NOT* thread safe yet! */
/** @todo Add exception handling for STL stuff! */

GuestProcessStreamBlock::GuestProcessStreamBlock()
{

}

/*
GuestProcessStreamBlock::GuestProcessStreamBlock(const GuestProcessStreamBlock &otherBlock)
{
    for (GuestCtrlStreamPairsIter it = otherBlock.m_mapPairs.begin();
         it != otherBlock.end(); it++)
    {
        m_mapPairs[it->first] = new
        if (it->second.pszValue)
        {
            RTMemFree(it->second.pszValue);
            it->second.pszValue = NULL;
        }
    }
}*/

GuestProcessStreamBlock::~GuestProcessStreamBlock()
{
    Clear();
}

/**
 * Destroys the currently stored stream pairs.
 *
 * @return  IPRT status code.
 */
void GuestProcessStreamBlock::Clear()
{
    m_mapPairs.clear();
}

#ifdef DEBUG
void GuestProcessStreamBlock::Dump()
{
    LogFlowFunc(("Dumping contents of stream block=0x%p (%ld items):\n",
                 this, m_mapPairs.size()));

    for (GuestCtrlStreamPairMapIterConst it = m_mapPairs.begin();
         it != m_mapPairs.end(); it++)
    {
        LogFlowFunc(("\t%s=%s\n", it->first.c_str(), it->second.mValue.c_str()));
    }
}
#endif

/**
 * Returns a 64-bit signed integer of a specified key.
 *
 * @return  IPRT status code. VERR_NOT_FOUND if key was not found.
 * @param  pszKey               Name of key to get the value for.
 * @param  piVal                Pointer to value to return.
 */
int GuestProcessStreamBlock::GetInt64Ex(const char *pszKey, int64_t *piVal)
{
    AssertPtrReturn(pszKey, VERR_INVALID_POINTER);
    AssertPtrReturn(piVal, VERR_INVALID_POINTER);
    const char *pszValue = GetString(pszKey);
    if (pszValue)
    {
        *piVal = RTStrToInt64(pszValue);
        return VINF_SUCCESS;
    }
    return VERR_NOT_FOUND;
}

/**
 * Returns a 64-bit integer of a specified key.
 *
 * @return  int64_t             Value to return, 0 if not found / on failure.
 * @param   pszKey              Name of key to get the value for.
 */
int64_t GuestProcessStreamBlock::GetInt64(const char *pszKey)
{
    int64_t iVal;
    if (RT_SUCCESS(GetInt64Ex(pszKey, &iVal)))
        return iVal;
    return 0;
}

/**
 * Returns the current number of stream pairs.
 *
 * @return  uint32_t            Current number of stream pairs.
 */
size_t GuestProcessStreamBlock::GetCount()
{
    return m_mapPairs.size();
}

/**
 * Returns a string value of a specified key.
 *
 * @return  uint32_t            Pointer to string to return, NULL if not found / on failure.
 * @param   pszKey              Name of key to get the value for.
 */
const char* GuestProcessStreamBlock::GetString(const char *pszKey)
{
    AssertPtrReturn(pszKey, NULL);

    try
    {
        GuestCtrlStreamPairMapIterConst itPairs = m_mapPairs.find(Utf8Str(pszKey));
        if (itPairs != m_mapPairs.end())
            return itPairs->second.mValue.c_str();
    }
    catch (const std::exception &ex)
    {
        NOREF(ex);
    }
    return NULL;
}

/**
 * Returns a 32-bit unsigned integer of a specified key.
 *
 * @return  IPRT status code. VERR_NOT_FOUND if key was not found.
 * @param  pszKey               Name of key to get the value for.
 * @param  puVal                Pointer to value to return.
 */
int GuestProcessStreamBlock::GetUInt32Ex(const char *pszKey, uint32_t *puVal)
{
    AssertPtrReturn(pszKey, VERR_INVALID_POINTER);
    AssertPtrReturn(puVal, VERR_INVALID_POINTER);
    const char *pszValue = GetString(pszKey);
    if (pszValue)
    {
        *puVal = RTStrToUInt32(pszValue);
        return VINF_SUCCESS;
    }
    return VERR_NOT_FOUND;
}

/**
 * Returns a 32-bit unsigned integer of a specified key.
 *
 * @return  uint32_t            Value to return, 0 if not found / on failure.
 * @param   pszKey              Name of key to get the value for.
 */
uint32_t GuestProcessStreamBlock::GetUInt32(const char *pszKey)
{
    uint32_t uVal;
    if (RT_SUCCESS(GetUInt32Ex(pszKey, &uVal)))
        return uVal;
    return 0;
}

/**
 * Sets a value to a key or deletes a key by setting a NULL value.
 *
 * @return  IPRT status code.
 * @param   pszKey              Key name to process.
 * @param   pszValue            Value to set. Set NULL for deleting the key.
 */
int GuestProcessStreamBlock::SetValue(const char *pszKey, const char *pszValue)
{
    AssertPtrReturn(pszKey, VERR_INVALID_POINTER);

    int rc = VINF_SUCCESS;
    try
    {
        Utf8Str Utf8Key(pszKey);

        /* Take a shortcut and prevent crashes on some funny versions
         * of STL if map is empty initially. */
        if (!m_mapPairs.empty())
        {
            GuestCtrlStreamPairMapIter it = m_mapPairs.find(Utf8Key);
            if (it != m_mapPairs.end())
                 m_mapPairs.erase(it);
        }

        if (pszValue)
        {
            GuestProcessStreamValue val(pszValue);
            m_mapPairs[Utf8Key] = val;
        }
    }
    catch (const std::exception &ex)
    {
        NOREF(ex);
    }
    return rc;
}

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

GuestProcessStream::GuestProcessStream()
    : m_cbAllocated(0),
      m_cbSize(0),
      m_cbOffset(0),
      m_pbBuffer(NULL)
{

}

GuestProcessStream::~GuestProcessStream()
{
    Destroy();
}

/**
 * Adds data to the internal parser buffer. Useful if there
 * are multiple rounds of adding data needed.
 *
 * @return  IPRT status code.
 * @param   pbData              Pointer to data to add.
 * @param   cbData              Size (in bytes) of data to add.
 */
int GuestProcessStream::AddData(const BYTE *pbData, size_t cbData)
{
    AssertPtrReturn(pbData, VERR_INVALID_POINTER);
    AssertReturn(cbData, VERR_INVALID_PARAMETER);

    int rc = VINF_SUCCESS;

    /* Rewind the buffer if it's empty. */
    size_t     cbInBuf   = m_cbSize - m_cbOffset;
    bool const fAddToSet = cbInBuf == 0;
    if (fAddToSet)
        m_cbSize = m_cbOffset = 0;

    /* Try and see if we can simply append the data. */
    if (cbData + m_cbSize <= m_cbAllocated)
    {
        memcpy(&m_pbBuffer[m_cbSize], pbData, cbData);
        m_cbSize += cbData;
    }
    else
    {
        /* Move any buffered data to the front. */
        cbInBuf = m_cbSize - m_cbOffset;
        if (cbInBuf == 0)
            m_cbSize = m_cbOffset = 0;
        else if (m_cbOffset) /* Do we have something to move? */
        {
            memmove(m_pbBuffer, &m_pbBuffer[m_cbOffset], cbInBuf);
            m_cbSize = cbInBuf;
            m_cbOffset = 0;
        }

        /* Do we need to grow the buffer? */
        if (cbData + m_cbSize > m_cbAllocated)
        {
            size_t cbAlloc = m_cbSize + cbData;
            cbAlloc = RT_ALIGN_Z(cbAlloc, _64K);
            void *pvNew = RTMemRealloc(m_pbBuffer, cbAlloc);
            if (pvNew)
            {
                m_pbBuffer = (uint8_t *)pvNew;
                m_cbAllocated = cbAlloc;
            }
            else
                rc = VERR_NO_MEMORY;
        }

        /* Finally, copy the data. */
        if (RT_SUCCESS(rc))
        {
            if (cbData + m_cbSize <= m_cbAllocated)
            {
                memcpy(&m_pbBuffer[m_cbSize], pbData, cbData);
                m_cbSize += cbData;
            }
            else
                rc = VERR_BUFFER_OVERFLOW;
        }
    }

    return rc;
}

/**
 * Destroys the the internal data buffer.
 */
void GuestProcessStream::Destroy()
{
    if (m_pbBuffer)
    {
        RTMemFree(m_pbBuffer);
        m_pbBuffer = NULL;
    }

    m_cbAllocated = 0;
    m_cbSize = 0;
    m_cbOffset = 0;
}

#ifdef DEBUG
void GuestProcessStream::Dump(const char *pszFile)
{
    LogFlowFunc(("Dumping contents of stream=0x%p (cbAlloc=%u, cbSize=%u, cbOff=%u) to %s\n",
                 m_pbBuffer, m_cbAllocated, m_cbSize, m_cbOffset, pszFile));

    RTFILE hFile;
    int rc = RTFileOpen(&hFile, pszFile, RTFILE_O_CREATE_REPLACE | RTFILE_O_WRITE | RTFILE_O_DENY_WRITE);
    if (RT_SUCCESS(rc))
    {
        rc = RTFileWrite(hFile, m_pbBuffer, m_cbSize, NULL /* pcbWritten */);
        RTFileClose(hFile);
    }
}
#endif

/**
 * Returns the current offset of the parser within
 * the internal data buffer.
 *
 * @return  uint32_t            Parser offset.
 */
uint32_t GuestProcessStream::GetOffset()
{
    return m_cbOffset;
}

uint32_t GuestProcessStream::GetSize()
{
    return m_cbSize;
}

/**
 * Tries to parse the next upcoming pair block within the internal
 * buffer.
 *
 * Returns VERR_NO_DATA is no data is in internal buffer or buffer has been
 * completely parsed already.
 *
 * Returns VERR_MORE_DATA if current block was parsed (with zero or more pairs
 * stored in stream block) but still contains incomplete (unterminated)
 * data.
 *
 * Returns VINF_SUCCESS if current block was parsed until the next upcoming
 * block (with zero or more pairs stored in stream block).
 *
 * @return IPRT status code.
 * @param streamBlock               Reference to guest stream block to fill.
 *
 */
int GuestProcessStream::ParseBlock(GuestProcessStreamBlock &streamBlock)
{
    if (   !m_pbBuffer
        || !m_cbSize)
    {
        return VERR_NO_DATA;
    }

    AssertReturn(m_cbOffset <= m_cbSize, VERR_INVALID_PARAMETER);
    if (m_cbOffset == m_cbSize)
        return VERR_NO_DATA;

    int rc = VINF_SUCCESS;

    char    *pszOff    = (char*)&m_pbBuffer[m_cbOffset];
    char    *pszStart  = pszOff;
    uint32_t uDistance;
    while (*pszStart)
    {
        size_t pairLen = strlen(pszStart);
        uDistance = (pszStart - pszOff);
        if (m_cbOffset + uDistance + pairLen + 1 >= m_cbSize)
        {
            rc = VERR_MORE_DATA;
            break;
        }
        else
        {
            char *pszSep = strchr(pszStart, '=');
            char *pszVal = NULL;
            if (pszSep)
                pszVal = pszSep + 1;
            if (!pszSep || !pszVal)
            {
                rc = VERR_MORE_DATA;
                break;
            }

            /* Terminate the separator so that we can
             * use pszStart as our key from now on. */
            *pszSep = '\0';

            rc = streamBlock.SetValue(pszStart, pszVal);
            if (RT_FAILURE(rc))
                return rc;
        }

        /* Next pair. */
        pszStart += pairLen + 1;
    }

    /* If we did not do any movement but we have stuff left
     * in our buffer just skip the current termination so that
     * we can try next time. */
    uDistance = (pszStart - pszOff);
    if (   !uDistance
        && *pszStart == '\0'
        && m_cbOffset < m_cbSize)
    {
        uDistance++;
    }
    m_cbOffset += uDistance;

    return rc;
}