/*

 * ultra.c

 *

 * Routines to implement ultra based encoding (minilzo).

 * ultrazip supports packed rectangles if the rects are tiny...

 * This improves performance as lzo has more data to work with at once

 * This is 'UltraZip' and is currently not implemented.

 */

#include <rfb/rfb.h>

#ifdef LIBVNCSERVER_HAVE_LZO

#include <lzo/lzo1x.h>

#else

#include "minilzo.h"

#endif

/*

 * cl->beforeEncBuf contains pixel data in the client's format.

 * cl->afterEncBuf contains the lzo (deflated) encoding version.

 * If the lzo compressed/encoded version is

 * larger than the raw data or if it exceeds cl->afterEncBufSize then

 * raw encoding is used instead.

 */

/*

 * rfbSendOneRectEncodingZlib - send a given rectangle using one Zlib

 *                              rectangle encoding.

 */

#define MAX_WRKMEM ((LZO1X_1_MEM_COMPRESS) + (sizeof(lzo_align_t) - 1)) / sizeof(lzo_align_t)

void rfbFreeUltraData(rfbClientPtr cl) {

  if (cl->compStreamInitedLZO) {

    free(cl->lzoWrkMem);

    cl->compStreamInitedLZO=FALSE;

  }

}

static rfbBool

rfbSendOneRectEncodingUltra(rfbClientPtr cl,

                           int x,

                           int y,

                           int w,

                           int h)

{

    rfbFramebufferUpdateRectHeader rect;

    rfbZlibHeader hdr;

    int deflateResult;

    int i;

    char *fbptr = (cl->scaledScreen->frameBuffer + (cl->scaledScreen->paddedWidthInBytes * y)

         + (x * (cl->scaledScreen->bitsPerPixel / 8)));

    int maxRawSize;

    lzo_uint maxCompSize;

    maxRawSize = (w * h * (cl->format.bitsPerPixel / 8));

    if (!cl->beforeEncBuf || cl->beforeEncBufSize < maxRawSize) {

        if (cl->beforeEncBuf == NULL)

            cl->beforeEncBuf = (char *)malloc(maxRawSize);

        else {

            char *reallocedBeforeEncBuf = (char *)realloc(cl->beforeEncBuf, maxRawSize);

            if (!reallocedBeforeEncBuf) return FALSE;

            cl->beforeEncBuf = reallocedBeforeEncBuf;

        }

        if(cl->beforeEncBuf)

            cl->beforeEncBufSize = maxRawSize;

    }

    /*

     * lzo requires output buffer to be slightly larger than the input

     * buffer, in the worst case.

     */

    maxCompSize = (maxRawSize + maxRawSize / 16 + 64 + 3);

    if (!cl->afterEncBuf || cl->afterEncBufSize < (int)maxCompSize) {

        if (cl->afterEncBuf == NULL)

            cl->afterEncBuf = (char *)malloc(maxCompSize);

        else {

            char *reallocedAfterEncBuf = (char *)realloc(cl->afterEncBuf, maxCompSize);

            if (!reallocedAfterEncBuf) return FALSE;

            cl->afterEncBuf = reallocedAfterEncBuf;

        }

        if(cl->afterEncBuf)

            cl->afterEncBufSize = maxCompSize;

    }

    if (!cl->beforeEncBuf || !cl->afterEncBuf)

    {

        rfbLog("rfbSendOneRectEncodingUltra: failed to allocate memory\n");

        return FALSE;

    }

    /* 

     * Convert pixel data to client format.

     */

    (*cl->translateFn)(cl->translateLookupTable, &cl->screen->serverFormat,

           &cl->format, fbptr, cl->beforeEncBuf,

           cl->scaledScreen->paddedWidthInBytes, w, h);

    if ( cl->compStreamInitedLZO == FALSE ) {

        cl->compStreamInitedLZO = TRUE;

        /* Work-memory needed for compression. Allocate memory in units

         * of `lzo_align_t' (instead of `char') to make sure it is properly aligned.

         */  

        cl->lzoWrkMem = malloc(sizeof(lzo_align_t) * (((LZO1X_1_MEM_COMPRESS) + (sizeof(lzo_align_t) - 1)) / sizeof(lzo_align_t)));

    }

    /* Perform the compression here. */

    deflateResult = lzo1x_1_compress((unsigned char *)cl->beforeEncBuf, (lzo_uint)w * h * (cl->format.bitsPerPixel / 8), (unsigned char *)cl->afterEncBuf, &maxCompSize, cl->lzoWrkMem);

    /* maxCompSize now contains the compressed size */

    /* Find the total size of the resulting compressed data. */

    cl->afterEncBufLen = maxCompSize;

    if ( deflateResult != LZO_E_OK ) {

        rfbErr("lzo deflation error: %d\n", deflateResult);

        return FALSE;

    }

    /* Update statics */

    rfbStatRecordEncodingSent(cl, rfbEncodingUltra, sz_rfbFramebufferUpdateRectHeader + sz_rfbZlibHeader + cl->afterEncBufLen, maxRawSize);

    if (cl->ublen + sz_rfbFramebufferUpdateRectHeader + sz_rfbZlibHeader

  > UPDATE_BUF_SIZE)

    {

  if (!rfbSendUpdateBuf(cl))

      return FALSE;

    }

    rect.r.x = Swap16IfLE(x);

    rect.r.y = Swap16IfLE(y);

    rect.r.w = Swap16IfLE(w);

    rect.r.h = Swap16IfLE(h);

    rect.encoding = Swap32IfLE(rfbEncodingUltra);

    memcpy(&cl->updateBuf[cl->ublen], (char *)&rect,

     sz_rfbFramebufferUpdateRectHeader);

    cl->ublen += sz_rfbFramebufferUpdateRectHeader;

    hdr.nBytes = Swap32IfLE(cl->afterEncBufLen);

    memcpy(&cl->updateBuf[cl->ublen], (char *)&hdr, sz_rfbZlibHeader);

    cl->ublen += sz_rfbZlibHeader;

    /* We might want to try sending the data directly... */

    for (i = 0; i < cl->afterEncBufLen;) {

  int bytesToCopy = UPDATE_BUF_SIZE - cl->ublen;

  if (i + bytesToCopy > cl->afterEncBufLen) {

      bytesToCopy = cl->afterEncBufLen - i;

  }

  memcpy(&cl->updateBuf[cl->ublen], &cl->afterEncBuf[i], bytesToCopy);

  cl->ublen += bytesToCopy;

  i += bytesToCopy;

  if (cl->ublen == UPDATE_BUF_SIZE) {

      if (!rfbSendUpdateBuf(cl))

    return FALSE;

  }

    }

    return TRUE;

}

/*

 * rfbSendRectEncodingUltra - send a given rectangle using one or more

 *                           LZO encoding rectangles.

 */

rfbBool

rfbSendRectEncodingUltra(rfbClientPtr cl,

                        int x,

                        int y,

                        int w,

                        int h)

{

    int  maxLines;

    int  linesRemaining;

    rfbRectangle partialRect;

    partialRect.x = x;

    partialRect.y = y;

    partialRect.w = w;

    partialRect.h = h;

    /* Determine maximum pixel/scan lines allowed per rectangle. */

    maxLines = ( ULTRA_MAX_SIZE(w) / w );

    /* Initialize number of scan lines left to do. */

    linesRemaining = h;

    /* Loop until all work is done. */

    while ( linesRemaining > 0 ) {

        int linesToComp;

        if ( maxLines < linesRemaining )

            linesToComp = maxLines;

        else

            linesToComp = linesRemaining;

        partialRect.h = linesToComp;

        /* Encode (compress) and send the next rectangle. */

        if ( ! rfbSendOneRectEncodingUltra( cl,

                                           partialRect.x,

                                           partialRect.y,

                                           partialRect.w,

                                           partialRect.h )) {

            return FALSE;

        }

        /* Technically, flushing the buffer here is not extremely

         * efficient.  However, this improves the overall throughput

         * of the system over very slow networks.  By flushing

         * the buffer with every maximum size lzo rectangle, we

         * improve the pipelining usage of the server CPU, network,

         * and viewer CPU components.  Insuring that these components

         * are working in parallel actually improves the performance

         * seen by the user.

         * Since, lzo is most useful for slow networks, this flush

         * is appropriate for the desired behavior of the lzo encoding.

         */

        if (( cl->ublen > 0 ) &&

            ( linesToComp == maxLines )) {

            if (!rfbSendUpdateBuf(cl)) {

                return FALSE;

            }

        }

        /* Update remaining and incremental rectangle location. */

        linesRemaining -= linesToComp;

        partialRect.y += linesToComp;

    }

    return TRUE;

}