pdf.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

 * vAddFooter - add a page footer
 */
static void
vAddFooter(diagram_type *pDiag)
{
	const hdrftr_block_type *pFtrInfo;

	fail(pDiag == NULL);

	NO_DBG_MSG("vAddFooter");

	pFtrInfo = pGetHdrFtrInfo(iSectionIndex, FALSE,
					odd(iPageCount), bFirstInSection);
	bFirstInSection = FALSE;
	if (pFtrInfo == NULL ||
	    pFtrInfo->pText == NULL ||
	    pFtrInfo->lHeight <= 0) {
		fail(pFtrInfo != NULL && pFtrInfo->lHeight < 0);
		fail(pFtrInfo != NULL &&
			pFtrInfo->pText != NULL &&
			pFtrInfo->lHeight == 0);
		return;
	}

	bInFtrSpace = TRUE;

	DBG_DEC_C(pFtrInfo->lHeight != lFooterHeight, pFtrInfo->lHeight);
	DBG_DEC_C(pFtrInfo->lHeight != lFooterHeight, lFooterHeight);
	DBG_DEC_C(pDiag->lYtop < lFooterHeight + PS_BOTTOM_MARGIN,
			pDiag->lYtop);
	DBG_DEC_C(pDiag->lYtop < lFooterHeight + PS_BOTTOM_MARGIN,
			lFooterHeight + PS_BOTTOM_MARGIN);

	if (pDiag->lYtop > lFooterHeight + PS_BOTTOM_MARGIN) {
		/* Move down to the start of the footer */
		pDiag->lYtop = lFooterHeight + PS_BOTTOM_MARGIN;
		vMoveTo(pDiag, 0);
	} else if (pDiag->lYtop < lFooterHeight + PS_BOTTOM_MARGIN / 2) {
		DBG_FIXME();
		/*
		 * Move up to the start of the footer, to prevent moving
		 * of the bottom edge of the paper
		 */
		pDiag->lYtop = lFooterHeight + PS_BOTTOM_MARGIN;
		vMoveTo(pDiag, 0);
	}

	DBG_FLT_C(pDiag->lYtop < lFooterHeight + PS_BOTTOM_MARGIN,
	dDrawUnits2Points(lFooterHeight + PS_BOTTOM_MARGIN - pDiag->lYtop));

	vAddHdrFtr(pDiag, pFtrInfo);
	bInFtrSpace = FALSE;
} /* end of vAddFooter */

/*
 * vEndPageObject - end the current page object
 */
static void
vEndPageObject(FILE *pOutFile)
{
	long	lStreamEnd;

	if (lStreamStart < 0) {
		/* There is no current page object */
		return;
	}

	vFPprintf(pOutFile, "ET\n");
	lStreamEnd = lFilePosition;
	vFPprintf(pOutFile, "endstream\n");
	vFPprintf(pOutFile, "endobj\n");

	iObjectNumberCurr++;
	vSetLocation(iObjectNumberCurr);
	vFPprintf(pOutFile, "%d 0 obj\n", iObjectNumberCurr);
	vFPprintf(pOutFile, "%lu\n", lStreamEnd - lStreamStart);
	vFPprintf(pOutFile, "endobj\n");
} /* end of vEndPageObject */

/*
 * vMove2NextPage - move to the start of the next page
 */
static void
vMove2NextPage(diagram_type *pDiag, BOOL bNewSection)
{
	FILE	*pOutFile;

	fail(pDiag == NULL);
	fail(pDiag->pOutFile == NULL);

	pOutFile = pDiag->pOutFile;

	vAddFooter(pDiag);
	/* End the old page object */
	vEndPageObject(pOutFile);
	if (bNewSection) {
		iSectionIndex++;
		bFirstInSection = TRUE;
	}

	/* Start the new page object */
	iObjectNumberCurr++;
	vSetLocation(iObjectNumberCurr);
	vFillNextPageObject();
	vFPprintf(pOutFile, "%d 0 obj\n", iObjectNumberCurr);
	vFPprintf(pOutFile, "<<\n");
	vFPprintf(pOutFile, "/Type /Page\n");
	vFPprintf(pOutFile, "/Parent 3 0 R\n");
	vFPprintf(pOutFile, "/Resources 17 0 R\n");
	vFPprintf(pOutFile, "/Contents %d 0 R\n", iObjectNumberCurr + 1);
	vFPprintf(pOutFile, ">>\n");
	vFPprintf(pOutFile, "endobj\n");

	/* Start the new text object */
	iObjectNumberCurr++;
	vSetLocation(iObjectNumberCurr);
	vFPprintf(pOutFile, "%d 0 obj\n", iObjectNumberCurr);
	vFPprintf(pOutFile, "<<\n");
	vFPprintf(pOutFile, "/Length %d 0 R\n", iObjectNumberCurr + 1);
	vFPprintf(pOutFile, ">>\n");
	vFPprintf(pOutFile, "stream\n");
	lStreamStart = lFilePosition;
	vFPprintf(pOutFile, "BT\n");

	/* Set variables to their start of page values */
	pDiag->lYtop = lPageHeight - PS_TOP_MARGIN;
	tFontRefCurr = (drawfile_fontref)-1;
	usFontSizeCurr = 0;
	iFontColorCurr = -1;
	lYtopCurr = -1;
	vAddHeader(pDiag);
} /* end of vMove2NextPage */

/*
 * vMoveTo - move to the specified X,Y coordinates
 *
 * Move the current position of the specified diagram to its X,Y coordinates,
 * start on a new page if needed
 */
static void
vMoveTo(diagram_type *pDiag, long lLastVerticalMovement)
{
	fail(pDiag == NULL);
	fail(pDiag->pOutFile == NULL);

	if (pDiag->lYtop <= lFooterHeight + PS_BOTTOM_MARGIN && !bInFtrSpace) {
		vMove2NextPage(pDiag, FALSE);
		/* Repeat the last vertical movement on the new page */
		pDiag->lYtop -= lLastVerticalMovement;
	}

	fail(pDiag->lYtop < lFooterHeight + PS_BOTTOM_MARGIN && !bInFtrSpace);
	DBG_DEC_C(pDiag->lYtop < PS_BOTTOM_MARGIN, pDiag->lYtop);
	fail(pDiag->lYtop < PS_BOTTOM_MARGIN / 3);

	if (pDiag->lYtop != lYtopCurr) {
		vFPprintf(pDiag->pOutFile, "1 0 0 1 %.2f %.2f Tm\n",
			dDrawUnits2Points(pDiag->lXleft + PS_LEFT_MARGIN),
			dDrawUnits2Points(pDiag->lYtop));
		lYtopCurr = pDiag->lYtop;
	}
} /* end of vMoveTo */

/*
 * vProloguePDF - set options and perform the PDF initialization
 */
void
vProloguePDF(diagram_type *pDiag,
	const char *szTask, const options_type *pOptions)
{
	FILE	*pOutFile;

	fail(pDiag == NULL);
	fail(pDiag->pOutFile == NULL);
	fail(pOptions == NULL);

	pOutFile = pDiag->pOutFile;

	eEncoding = pOptions->eEncoding;

	/* Create an empty location array */
	tLocations = INITIAL_LOCATION_SIZE;
	alLocation = xcalloc(tLocations, sizeof(long));

	/* Create an empty pageobject array */
	tMaxPageObjects = INITIAL_PAGEOBJECT_SIZE;
	aiPageObject = xcalloc(tMaxPageObjects, sizeof(int));

	if (pOptions->iPageHeight == INT_MAX) {
		lPageHeight = LONG_MAX;
	} else {
		lPageHeight = lPoints2DrawUnits(pOptions->iPageHeight);
	}
	DBG_DEC(lPageHeight);
	if (pOptions->iPageWidth == INT_MAX) {
		lPageWidth = LONG_MAX;
	} else {
		lPageWidth = lPoints2DrawUnits(pOptions->iPageWidth);
	}
	DBG_DEC(lPageWidth);
	lFooterHeight = 0;
	bInFtrSpace = FALSE;

	tFontRefCurr = (drawfile_fontref)-1;
	usFontSizeCurr = 0;
	iFontColorCurr = -1;
	lYtopCurr = -1;
	iPageCount = 0;
	iImageCount = 0;
	iSectionIndex = 0;
	bFirstInSection = TRUE;
	lFilePosition = 0;
	iMaxLocationNumber = 0;
	lStreamStart = -1;
	iObjectNumberCurr = 17;
	pDiag->lXleft = 0;
	pDiag->lYtop = 0;

	szProducer = szTask;

	vFPprintf(pOutFile, "%%PDF-1.3\n");
	vFPprintf(pOutFile, "%%%c%c%c%c\n", 0xe2, 0xe3, 0xcf, 0xd3);

	/* Root catalog */
	vSetLocation(1);
	vFPprintf(pOutFile, "1 0 obj\n");
	vFPprintf(pOutFile, "<<\n");
	vFPprintf(pOutFile, "/Type /Catalog\n");
	vFPprintf(pOutFile, "/Pages 3 0 R\n");
	vFPprintf(pOutFile, ">>\n");
	vFPprintf(pOutFile, "endobj\n");
} /* end of vProloguePDF */

/*
 * vEpiloguePDF - clean up after everything is done
 */
void
vEpiloguePDF(diagram_type *pDiag)
{
	FILE	*pOutFile;
	long	lXref;
	int	iIndex;

	fail(pDiag == NULL);
	fail(pDiag->pOutFile == NULL);

	pOutFile = pDiag->pOutFile;

	vAddFooter(pDiag);
	/* End the old page object */
	vEndPageObject(pOutFile);

	vSetLocation(3);
	vFPprintf(pOutFile, "3 0 obj\n");
	vFPprintf(pOutFile, "<<\n");
	vFPprintf(pOutFile, "/Type /Pages\n");
	vFPprintf(pOutFile, "/Count %d\n", iPageCount);
	vFPprintf(pOutFile, "/MediaBox [ 0 0 %.0f %.0f ]\n",
			dDrawUnits2Points(lPageWidth),
			dDrawUnits2Points(lPageHeight));
	vFPprintf(pOutFile, "/Kids [ ");
	for (iIndex = 1; iIndex <= iPageCount; iIndex++) {
		vFPprintf(pOutFile, "\t%d 0 R\n", aiPageObject[iIndex]);
	}
	vFPprintf(pOutFile, "]\n");
	vFPprintf(pOutFile, ">>\n");
	vFPprintf(pOutFile, "endobj\n");

	lXref = lFilePosition;

	vFPprintf(pOutFile, "xref\n");
	vFPprintf(pOutFile, "0 %d\n", iMaxLocationNumber + 1);
	vFPprintf(pOutFile, "0000000000 65535 f \n");
	for (iIndex = 1; iIndex <= iMaxLocationNumber; iIndex++) {
		vFPprintf(pOutFile, "%.10ld 00000 n \n", alLocation[iIndex]);
	}

	vFPprintf(pOutFile, "trailer\n");
	vFPprintf(pOutFile, "<<\n");
	vFPprintf(pOutFile, "/Size %d\n", iMaxLocationNumber + 1);
	vFPprintf(pOutFile, "/Root 1 0 R\n");
	vFPprintf(pOutFile, "/Info 2 0 R\n");
	vFPprintf(pOutFile, ">>\n");

	vFPprintf(pOutFile, "startxref\n");
	vFPprintf(pOutFile, "%ld\n", lXref);
	vFPprintf(pOutFile, "%%%%EOF\n");

	szProducer = NULL;
	aiPageObject = xfree(aiPageObject);
	alLocation = xfree(alLocation);
} /* end of vEpiloguePDF */

/*
 * vPrintPalette - print a pdf color space (palette)
 */
static void
vPrintPalette(FILE *pOutFile, const imagedata_type *pImg)
{
	int	iIndex;

	fail(pOutFile == NULL);
	fail(pImg == NULL);
	fail(pImg->iColorsUsed < 2);
	fail(pImg->iColorsUsed > 256);

	vFPprintf(pOutFile, "\t/ColorSpace [ /Indexed\n");
	vFPprintf(pOutFile, "\t/Device%s %d\n",
		pImg->bColorImage ? "RGB" : "Gray", pImg->iColorsUsed - 1);
	vFPprintf(pOutFile, "<");
	for (iIndex = 0; iIndex < pImg->iColorsUsed; iIndex++) {
		vFPprintf(pOutFile, "%02x",
				(unsigned int)pImg->aucPalette[iIndex][0]);
		if (pImg->bColorImage) {
			vFPprintf(pOutFile, "%02x%02x",
				(unsigned int)pImg->aucPalette[iIndex][1],
				(unsigned int)pImg->aucPalette[iIndex][2]);
		}
		if (iIndex % 8 == 7) {
			vFPprintf(pOutFile, "\n");
		} else {
			vFPprintf(pOutFile, " ");
		}
	}
	vFPprintf(pOutFile, "> ]\n");
} /* end of vPrintPalette */

/*
 * vImageProloguePDF - perform the image initialization
 */
void
vImageProloguePDF(diagram_type *pDiag, const imagedata_type *pImg)
{
	FILE	*pOutFile;

	fail(pDiag == NULL);
	fail(pDiag->pOutFile == NULL);
	fail(pImg == NULL);

	if (pImg->iVerSizeScaled <= 0 || pImg->iHorSizeScaled <= 0) {
		return;
	}

	iImageCount++;

	DBG_DEC_C(pDiag->lXleft != 0, pDiag->lXleft);

	pDiag->lYtop -= lPoints2DrawUnits(pImg->iVerSizeScaled);
	vMoveTo(pDiag, lPoints2DrawUnits(pImg->iVerSizeScaled));

	pOutFile = pDiag->pOutFile;

	vFPprintf(pOutFile, "ET\n");
	vFPprintf(pOutFile, "q %% Image %03d\n", iImageCount);
	if (pImg->eImageType == imagetype_is_dib) {
		/* Scanning from left to right and bottom to top */
		vFPprintf(pOutFile, "%d 0 0 %d %.2f %.2f cm\n",
			pImg->iHorSizeScaled, -pImg->iVerSizeScaled,
			dDrawUnits2Points(pDiag->lXleft + PS_LEFT_MARGIN),
			dDrawUnits2Points(pDiag->lYtop) + pImg->iVerSizeScaled);
	} else {
		/* Scanning from left to right and top to bottom */
		vFPprintf(pOutFile, "%d 0 0 %d %.2f %.2f cm\n",
			pImg->iHorSizeScaled, pImg->iVerSizeScaled,
			dDrawUnits2Points(pDiag->lXleft + PS_LEFT_MARGIN),
			dDrawUnits2Points(pDiag->lYtop));
	}
	vFPprintf(pOutFile, "BI\n");
	vFPprintf(pOutFile, "\t/Width %d\n", pImg->iWidth);
	vFPprintf(pOutFile, "\t/Height %d\n", pImg->iHeight);
	switch (pImg->eImageType) {
	case imagetype_is_jpeg:
		switch (pImg->iComponents) {
		case 1:
			vFPprintf(pOutFile, "\t/ColorSpace /DeviceGray\n");
			break;
		case 3:
			vFPprintf(pOutFile, "\t/ColorSpace /DeviceRGB\n");
			break;
		case 4:
			vFPprintf(pOutFile, "\t/ColorSpace /DeviceCMYK\n");
			if (pImg->bAdobe) {
				/*