Mozilla/mozilla/layout/html/base/src/nsHTMLImageLoader.cpp
jaggernaut%netscape.com 436d43f211 Bug 104158: Use NS_LITERAL_STRING instead of XXXWithConversion("..."). r=bryner, rs=alecf
git-svn-id: svn://10.0.0.236/trunk@110579 18797224-902f-48f8-a5cc-f745e15eee43
2001-12-16 11:58:03 +00:00

581 lines
19 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: NPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Netscape Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/NPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the NPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the NPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsHTMLImageLoader.h"
#include "nsIStyleContext.h"
#include "nsFrame.h"
#include "nsIURL.h"
#include "nsNetUtil.h"
#ifdef DEBUG
#undef NOISY_IMAGE_LOADING
#else
#undef NOISY_IMAGE_LOADING
#endif
MOZ_DECL_CTOR_COUNTER(nsHTMLImageLoader)
nsHTMLImageLoader::nsHTMLImageLoader()
: mBaseURL(nsnull),
mFrame(nsnull),
mCallBack(nsnull),
mClosure(nsnull),
mImageLoader(nsnull),
mAllFlags(0),
mIntrinsicImageSize(0, 0),
mComputedImageSize(0, 0)
{
MOZ_COUNT_CTOR(nsHTMLImageLoader);
}
nsHTMLImageLoader::~nsHTMLImageLoader()
{
MOZ_COUNT_DTOR(nsHTMLImageLoader);
NS_IF_RELEASE(mBaseURL);
NS_IF_RELEASE(mImageLoader);
}
void
nsHTMLImageLoader::Init(nsIFrame* aFrame,
nsHTMLImageLoaderCB aCallBack,
void* aClosure,
nsIURI* aBaseURL,
const nsString& aURLSpec)
{
mFrame = aFrame;
mCallBack = aCallBack;
mClosure = aClosure;
mBaseURL = aBaseURL;
NS_IF_ADDREF(mBaseURL);
SetURL(aURLSpec);
}
nsIImage*
nsHTMLImageLoader::GetImage()
{
nsIImage* image = nsnull;
if (mImageLoader) {
mImageLoader->GetImage(&image);
}
return image;
}
void
nsHTMLImageLoader::GetNaturalImageSize(PRUint32* naturalWidth, PRUint32* naturalHeight)
{
*naturalWidth = 0;
*naturalHeight = 0;
if (mImageLoader) {
mImageLoader->GetNaturalImageSize(naturalWidth, naturalHeight);
}
}
void
nsHTMLImageLoader::SetURL(const nsString& aNewSpec)
{
mURLSpec = aNewSpec;
mURLSpec.Trim(" \t\n\r");
if (mBaseURL && !aNewSpec.IsEmpty()) {
nsString empty;
nsresult rv;
rv = NS_MakeAbsoluteURI(mURL, mURLSpec, mBaseURL);
if (NS_FAILED(rv)) {
mURL = mURLSpec;
}
} else {
mURL = mURLSpec;
}
}
void
nsHTMLImageLoader::StopLoadImage(nsIPresContext* aPresContext)
{
if (mImageLoader) {
aPresContext->StopLoadImage(mFrame, mImageLoader);
NS_RELEASE(mImageLoader);
}
}
void
nsHTMLImageLoader::StopAllLoadImages(nsIPresContext* aPresContext)
{
aPresContext->StopAllLoadImagesFor(mFrame, mFrame);
}
nsresult
nsHTMLImageLoader::ImageLoadCB(nsIPresContext* aPresContext,
nsIFrameImageLoader* aLoader,
nsIFrame* aFrame,
void* aClosure,
PRUint32 aStatus)
{
if (aClosure) {
((nsHTMLImageLoader*)aClosure)->Update(aPresContext, aFrame, aStatus);
}
return NS_OK;
}
void
nsHTMLImageLoader::Update(nsIPresContext* aPresContext,
nsIFrame* aFrame,
PRUint32 aStatus)
{
#ifdef NOISY_IMAGE_LOADING
nsFrame::ListTag(stdout, aFrame);
printf(": update: status=%x [loader=%p] callBack=%p squelch=%s\n",
aStatus, mImageLoader, mCallBack,
mFlags.mSquelchCallback ? "yes" : "no");
#endif
if (!mFlags.mNeedSizeNotification &&
NS_IMAGE_LOAD_STATUS_SIZE_AVAILABLE & aStatus) {
// remove the size available bit since it is not needed
aStatus &= ~NS_IMAGE_LOAD_STATUS_SIZE_AVAILABLE;
// check if any status left
if (aStatus == NS_IMAGE_LOAD_STATUS_NONE)
return;
}
if (NS_IMAGE_LOAD_STATUS_SIZE_AVAILABLE & aStatus) {
if (mImageLoader) {
mImageLoader->GetSize(mIntrinsicImageSize);
if (mFlags.mNeedIntrinsicImageSize) {
mFlags.mHaveIntrinsicImageSize = PR_TRUE;
}
}
}
// Pass on update to the user of this object if they want it
if (mCallBack) {
// We squelch the status size callback in the case where the client doesn't
// want the size returned. However, don't squelch a status that says the image
// failed to load
if ((NS_IMAGE_LOAD_STATUS_ERROR & aStatus) || !mFlags.mSquelchCallback) {
(*mCallBack)(aPresContext, this, aFrame, mClosure, aStatus);
}
}
}
// The prefix for special "internal" images that are well known
#define GOPHER_SPEC "internal-gopher-"
// Note: sizeof a string constant includes the \0 at the end so
// subtract one
#define GOPHER_SPEC_SIZE (sizeof(GOPHER_SPEC) - 1)
nsresult
nsHTMLImageLoader::StartLoadImage(nsIPresContext* aPresContext)
{
if (!mFrame) {
// We were not initialized!
return NS_ERROR_NULL_POINTER;
}
if (mURL.IsEmpty()) {
return NS_OK;
}
// Note: navigator 4.* and earlier releases ignored the base tags
// effect on the builtin images. So we do too. Use mURLSpec instead
// of the absolute url...
nsAutoString internalImageURLSpec;
nsString* urlSpec = &mURL;
if (mURLSpec.CompareWithConversion(GOPHER_SPEC, PR_FALSE, GOPHER_SPEC_SIZE) == 0) {
// We found a special image source value that refers to a
// builtin image. Rewrite the source url as a resource url.
urlSpec = &internalImageURLSpec;
mURLSpec.Mid(internalImageURLSpec, GOPHER_SPEC_SIZE,
mURLSpec.Length() - GOPHER_SPEC_SIZE);
internalImageURLSpec = NS_LITERAL_STRING("resource:/res/html/gopher-") +
internalImageURLSpec +
NS_LITERAL_STRING(".gif");
}
// This is kind of sick, but its possible that we will get a
// notification *before* we have setup mImageLoader. To get around
// this, we let the pres-context store into mImageLoader and sort
// things after it returns.
nsIFrameImageLoader* oldLoader = mImageLoader;
nsSize* sizeToLoadWidth = nsnull;
if (!mFlags.mAutoImageSize && !mFlags.mNeedIntrinsicImageSize) {
sizeToLoadWidth = &mComputedImageSize;
}
nsresult rv = aPresContext->StartLoadImage(*urlSpec, nsnull,
sizeToLoadWidth,
mFrame, ImageLoadCB, (void*)this,
mFrame, &mImageLoader);
#ifdef NOISY_IMAGE_LOADING
nsFrame::ListTag(stdout, mFrame);
printf(": loading image '");
fputs(NS_LossyConvertUCS2toASCII(mURL).get(), stdout);
printf("' @ ");
if (mFlags.mNeedIntrinsicImageSize) {
printf("intrinsic size ");
}
printf("%d,%d; oldLoader=%p newLoader=%p",
mComputedImageSize.width, mComputedImageSize.height,
oldLoader, mImageLoader);
if (sizeToLoadWidth) {
printf(" sizeToLoadWidth=%d,%d",
sizeToLoadWidth->width, sizeToLoadWidth->height);
}
else {
printf(" autoImageSize=%s needIntrinsicImageSize=%s",
mFlags.mAutoImageSize ? "yes" : "no",
mFlags.mNeedIntrinsicImageSize ? "yes" : "no");
}
printf("\n");
#endif
if (oldLoader != mImageLoader) {
if (nsnull != oldLoader) {
// Tell presentation context we are done with the old image loader
aPresContext->StopLoadImage(mFrame, oldLoader);
}
}
// Release the old image loader
NS_IF_RELEASE(oldLoader);
return rv;
}
void
nsHTMLImageLoader::UpdateURLSpec(nsIPresContext* aPresContext,
const nsString& aNewSpec)
{
SetURL(aNewSpec);
// Start image loading with the previously computed size information
StartLoadImage(aPresContext);
}
#define MINMAX(_value,_min,_max) \
((_value) < (_min) \
? (_min) \
: ((_value) > (_max) \
? (_max) \
: (_value)))
PRBool
nsHTMLImageLoader::GetDesiredSize(nsIPresContext* aPresContext,
const nsHTMLReflowState* aReflowState,
nsHTMLReflowMetrics& aDesiredSize)
{
nscoord widthConstraint = NS_INTRINSICSIZE;
nscoord heightConstraint = NS_INTRINSICSIZE;
PRBool fixedContentWidth = PR_FALSE;
PRBool fixedContentHeight = PR_FALSE;
if (mFlags.mInRecalcMode)
{ // only true after an unconstrained reflow of a %-width image recieved after we've fetched our intrinsic width
// really! This case is for bug 39901 and 38396. The point is, we've already
// calculated everything we need and we want to just return it right away.
// This is somewhat fragile, since it makes an assumption about the way reflow works.
mFlags.mInRecalcMode=0; // clear the mode
// block code will lie to us, so use our already-computed values
aDesiredSize.width = mComputedImageSize.width;
aDesiredSize.height = mComputedImageSize.height;
return PR_TRUE;
}
nscoord minWidth, maxWidth, minHeight, maxHeight;
if (aReflowState) {
// Determine whether the image has fixed content width
widthConstraint = aReflowState->mComputedWidth;
minWidth = aReflowState->mComputedMinWidth;
maxWidth = aReflowState->mComputedMaxWidth;
if (NS_INTRINSICSIZE != widthConstraint) {
fixedContentWidth = PR_TRUE;
}
else if (mFlags.mHaveIntrinsicImageSize) {
// At this point we know that the width value was not
// constrained and that we now know the intrinsic size of the
// image.
//
// The css2 spec states that if a min/max width value is
// provided then it acts as a substitute value for the "width"
// property, if it applies. Therefore, we will force the
// fixedContentWidth flag to true in these cases.
if ((0 != minWidth) ||
(NS_UNCONSTRAINEDSIZE != maxWidth))
{
// Use the intrinsic image width for the min-max comparisons,
// since the width property is "auto".
widthConstraint = mIntrinsicImageSize.width;
fixedContentWidth = PR_TRUE;
}
// Check the special case where we have the intrinsic width
// (already tested to get into this block of code)
// and it's an unconstrained reflow, and we are %-width
// This special case is for bug 39901 and 38396
else if (aReflowState &&
(NS_UNCONSTRAINEDSIZE == aReflowState->availableWidth) &&
(eStyleUnit_Percent==aReflowState->mStylePosition->mWidth.GetUnit()))
{
// Use the intrinsic image width
// since the width property is percent (uncalcuable at this time).
widthConstraint = mIntrinsicImageSize.width;
fixedContentWidth = PR_TRUE;
mFlags.mInRecalcMode = PR_TRUE; // we set up this state for bug 39901 and 38396
}
}
// Determine whether the image has fixed content height
heightConstraint = aReflowState->mComputedHeight;
minHeight = aReflowState->mComputedMinHeight;
maxHeight = aReflowState->mComputedMaxHeight;
if (NS_UNCONSTRAINEDSIZE != heightConstraint) {
fixedContentHeight = PR_TRUE;
}
else if (mFlags.mHaveIntrinsicImageSize) {
// At this point we know that the height value was not
// constrained and that we now know the intrinsic size of the
// image.
//
// The css2 spec states that if a min/max height value is
// provided then it acts as a substitute value for the "height"
// property, if it applies. Therefore, we will force the
// fixedContentHeight flag to true in these cases.
if ((0 != minHeight) ||
(NS_UNCONSTRAINEDSIZE != maxHeight)) {
// Use the intrinsic image height for the min-max comparisons,
// since the height property is "auto".
heightConstraint = mIntrinsicImageSize.height;
fixedContentHeight = PR_TRUE;
}
}
}
else {
minWidth = minHeight = 0;
maxWidth = maxHeight = NS_UNCONSTRAINEDSIZE;
}
float p2t, t2p;
aPresContext->GetPixelsToTwips(&p2t);
aPresContext->GetTwipsToPixels(&t2p);
for (;;) {
PRBool haveComputedSize = PR_FALSE;
PRBool needIntrinsicImageSize = PR_FALSE;
nscoord newWidth, newHeight;
mFlags.mAutoImageSize = PR_FALSE;
mFlags.mNeedSizeNotification = PR_FALSE;
if (fixedContentWidth) {
if (fixedContentHeight) {
newWidth = MINMAX(widthConstraint, minWidth, maxWidth);
newHeight = MINMAX(heightConstraint, minHeight, maxHeight);
haveComputedSize = PR_TRUE;
}
else {
// We have a width, and an auto height. Compute height from
// width once we have the intrinsic image size.
newWidth = MINMAX(widthConstraint, minWidth, maxWidth);
if (mFlags.mHaveIntrinsicImageSize) {
float width = mIntrinsicImageSize.width
? (float) mIntrinsicImageSize.width
: (float) mIntrinsicImageSize.height; // avoid divide by zero
float height = (float) mIntrinsicImageSize.height;
// snap the width to the nearest pixel value to prevent a
// feedback loop.
PRInt32 pixelWidth = NSTwipsToIntPixels(newWidth + nscoord(p2t / 2), t2p);
newWidth = NSIntPixelsToTwips(pixelWidth, p2t);
newHeight = (nscoord)
NSToIntRound(newWidth * height / width);
newHeight = MINMAX(newHeight, minHeight, maxHeight);
haveComputedSize = PR_TRUE;
}
else {
newHeight = 1;
needIntrinsicImageSize = PR_TRUE;
mFlags.mNeedSizeNotification = PR_TRUE;
}
}
}
else if (fixedContentHeight) {
// We have a height, and an auto width. Compute width from height
// once we have the intrinsic image size.
// otherwise, we really have auto-width based on height
newHeight = MINMAX(heightConstraint, minHeight, maxHeight);
if (mFlags.mHaveIntrinsicImageSize) {
float width = (float) mIntrinsicImageSize.width;
float height = mIntrinsicImageSize.height
? (float) mIntrinsicImageSize.height
: (float) mIntrinsicImageSize.width; // avoid divide by zero
// snap the height to the nearest pixel value to prevent a
// feedback loop.
PRInt32 pixelHeight = NSTwipsToIntPixels(newHeight + nscoord(p2t / 2), t2p);
newHeight = NSIntPixelsToTwips(pixelHeight, p2t);
newWidth = (nscoord)
NSToIntRound(newHeight * width / height);
newWidth = MINMAX(newWidth, minWidth, maxWidth);
haveComputedSize = PR_TRUE;
}
else {
newWidth = 1;
needIntrinsicImageSize = PR_TRUE;
mFlags.mNeedSizeNotification = PR_TRUE;
}
}
else {
mFlags.mAutoImageSize = PR_TRUE;
if (mFlags.mHaveIntrinsicImageSize) {
newWidth = MINMAX(mIntrinsicImageSize.width, minWidth, maxWidth);
newHeight = MINMAX(mIntrinsicImageSize.height, minHeight, maxHeight);
haveComputedSize = PR_TRUE;
}
else {
newWidth = 1;
newHeight = 1;
needIntrinsicImageSize = PR_TRUE;
mFlags.mNeedSizeNotification = PR_TRUE;
}
}
mFlags.mNeedIntrinsicImageSize = needIntrinsicImageSize;
mFlags.mHaveComputedSize = haveComputedSize;
mComputedImageSize.width = newWidth;
mComputedImageSize.height = newHeight;
#ifdef NOISY_IMAGE_LOADING
nsFrame::ListTag(stdout, mFrame);
printf(": %s%scomputedSize=%d,%d min=%d,%d max=%d,%d fixed=%s,%s\n",
mFlags.mNeedIntrinsicImageSize ? "need-instrinsic-size " : "",
mFlags.mHaveComputedSize ? "have-computed-size " : "",
mComputedImageSize.width, mComputedImageSize.height,
minWidth, minHeight, maxWidth, maxHeight,
fixedContentWidth ? "yes" : "no",
fixedContentHeight ? "yes" : "no");
#endif
// Load the image at the desired size
if ((0 != newWidth) && (0 != newHeight))
{
// Make sure we squelch a callback to the client of this image
// loader during a start-load-image. Its possible the image we
// want is ready to go and will therefore fire a notification
// during the StartLoadImage call. Since this routine is already
// returning size information there is no point in passing on the
// callbacks to the client.
mFlags.mSquelchCallback = PR_TRUE;
StartLoadImage(aPresContext);
mFlags.mSquelchCallback = PR_FALSE;
// See if we just got the intrinsic size
if (mFlags.mNeedIntrinsicImageSize && mFlags.mHaveIntrinsicImageSize) {
// We just learned our intrinisic size. Start over from the top...
#ifdef NOISY_IMAGE_LOADING
printf(" *** size arrived during StartLoadImage, looping...\n");
#endif
continue;
}
}
break;
}
aDesiredSize.width = mComputedImageSize.width;
aDesiredSize.height = mComputedImageSize.height;
#ifdef NOISY_IMAGE_LOADING
printf("nsHTMLImageLoader::GetDesiredSize returning %d, %d\n",
aDesiredSize.width, aDesiredSize.height);
#endif
if ((mFlags.mNeedIntrinsicImageSize && !mFlags.mHaveIntrinsicImageSize) ||
mFlags.mNeedSizeNotification) {
return PR_FALSE;
}
return PR_TRUE;
}
PRBool
nsHTMLImageLoader::GetLoadImageFailed() const
{
PRBool result = PR_FALSE;
if (nsnull != mImageLoader) {
// Ask the image loader whether the load failed
PRUint32 loadStatus;
mImageLoader->GetImageLoadStatus(&loadStatus);
result = 0 != (loadStatus & NS_IMAGE_LOAD_STATUS_ERROR);
return result;
}
result = mFlags.mLoadImageFailed ? PR_TRUE : PR_FALSE;
return result;
}
PRUint32
nsHTMLImageLoader::GetLoadStatus() const
{
PRUint32 loadStatus = NS_IMAGE_LOAD_STATUS_NONE;
if (mImageLoader) {
mImageLoader->GetImageLoadStatus(&loadStatus);
}
return loadStatus;
}
void
nsHTMLImageLoader::GetIntrinsicSize(nsSize& aSize)
{
if (mImageLoader) {
mImageLoader->GetIntrinsicSize(aSize);
} else {
aSize.SizeTo(0, 0);
}
}
#ifdef DEBUG
// Note: this doesn't factor in:
// -- the mBaseURL (it might be shared)
// -- the mFrame (that will be counted elsewhere most likely)
// -- the mClosure (we don't know what type it is)
// -- the mImageLoader (it might be shared)
void
nsHTMLImageLoader::SizeOf(nsISizeOfHandler* aHandler, PRUint32* aResult) const
{
PRUint32 sum = sizeof(*this) - sizeof(mURLSpec) - sizeof(mURL);
PRUint32 ss;
mURLSpec.SizeOf(aHandler, &ss); sum += ss;
mURL.SizeOf(aHandler, &ss); sum += ss;
*aResult = sum;
}
#endif