gfx/thebes/gfxSVGGlyphs.cpp

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #include "gfxSVGGlyphs.h"
   6
   7 #include "mozilla/BasePrincipal.h"
   8 #include "mozilla/LoadInfo.h"
   9 #include "mozilla/NullPrincipal.h"
  10 #include "mozilla/PresShell.h"
  11 #include "mozilla/SMILAnimationController.h"
  12 #include "mozilla/SVGContextPaint.h"
  13 #include "mozilla/SVGUtils.h"
  14 #include "mozilla/dom/Document.h"
  15 #include "mozilla/dom/Element.h"
  16 #include "mozilla/dom/FontTableURIProtocolHandler.h"
  17 #include "mozilla/dom/ImageTracker.h"
  18 #include "mozilla/dom/SVGDocument.h"
  19 #include "nsError.h"
  20 #include "nsString.h"
  21 #include "nsICategoryManager.h"
  22 #include "nsIDocumentLoaderFactory.h"
  23 #include "nsIContentViewer.h"
  24 #include "nsIStreamListener.h"
  25 #include "nsServiceManagerUtils.h"
  26 #include "nsNetUtil.h"
  27 #include "nsIInputStream.h"
  28 #include "nsStringStream.h"
  29 #include "nsStreamUtils.h"
  30 #include "nsIPrincipal.h"
  31 #include "nsContentUtils.h"
  32 #include "gfxFont.h"
  33 #include "gfxContext.h"
  34 #include "harfbuzz/hb.h"
  35 #include "zlib.h"
  36
  37 #define SVG_CONTENT_TYPE "image/svg+xml"_ns
  38 #define UTF8_CHARSET "utf-8"_ns
  39
  40 using namespace mozilla;
  41 using mozilla::dom::Document;
  42 using mozilla::dom::Element;
  43
  44 /* static */
  45 const mozilla::gfx::DeviceColor SimpleTextContextPaint::sZero;
  46
  47 gfxSVGGlyphs::gfxSVGGlyphs(hb_blob_t* aSVGTable, gfxFontEntry* aFontEntry)
  48     : mSVGData(aSVGTable), mFontEntry(aFontEntry) {
  49   unsigned int length;
  50   const char* svgData = hb_blob_get_data(mSVGData, &length);
  51   mHeader = reinterpret_cast<const Header*>(svgData);
  52   mDocIndex = nullptr;
  53
  54   if (sizeof(Header) <= length && uint16_t(mHeader->mVersion) == 0 &&
  55       uint64_t(mHeader->mDocIndexOffset) + 2 <= length) {
  56     const DocIndex* docIndex =
  57         reinterpret_cast<const DocIndex*>(svgData + mHeader->mDocIndexOffset);
  58     // Limit the number of documents to avoid overflow
  59     if (uint64_t(mHeader->mDocIndexOffset) + 2 +
  60             uint16_t(docIndex->mNumEntries) * sizeof(IndexEntry) <=
  61         length) {
  62       mDocIndex = docIndex;
  63     }
  64   }
  65 }
  66
  67 gfxSVGGlyphs::~gfxSVGGlyphs() { hb_blob_destroy(mSVGData); }
  68
  69 void gfxSVGGlyphs::DidRefresh() { mFontEntry->NotifyGlyphsChanged(); }
  70
  71 /*
  72  * Comparison operator for finding a range containing a given glyph ID. Simply
  73  *   checks whether |key| is less (greater) than every element of |range|, in
  74  *   which case return |key| < |range| (|key| > |range|). Otherwise |key| is in
  75  *   |range|, in which case return equality.
  76  * The total ordering here is guaranteed by
  77  *   (1) the index ranges being disjoint; and
  78  *   (2) the (sole) key always being a singleton, so intersection => containment
  79  *       (note that this is wrong if we have more than one intersection or two
  80  *        sets intersecting of size > 1 -- so... don't do that)
  81  */
  82 /* static */
  83 int gfxSVGGlyphs::CompareIndexEntries(const void* aKey, const void* aEntry) {
  84   const uint32_t key = *(uint32_t*)aKey;
  85   const IndexEntry* entry = (const IndexEntry*)aEntry;
  86
  87   if (key < uint16_t(entry->mStartGlyph)) {
  88     return -1;
  89   }
  90   if (key > uint16_t(entry->mEndGlyph)) {
  91     return 1;
  92   }
  93   return 0;
  94 }
  95
  96 gfxSVGGlyphsDocument* gfxSVGGlyphs::FindOrCreateGlyphsDocument(
  97     uint32_t aGlyphId) {
  98   if (!mDocIndex) {
  99     // Invalid table
 100     return nullptr;
 101   }
 102
 103   IndexEntry* entry = (IndexEntry*)bsearch(
 104       &aGlyphId, mDocIndex->mEntries, uint16_t(mDocIndex->mNumEntries),
 105       sizeof(IndexEntry), CompareIndexEntries);
 106   if (!entry) {
 107     return nullptr;
 108   }
 109
 110   return mGlyphDocs.WithEntryHandle(
 111       entry->mDocOffset, [&](auto&& glyphDocsEntry) -> gfxSVGGlyphsDocument* {
 112         if (!glyphDocsEntry) {
 113           unsigned int length;
 114           const uint8_t* data =
 115               (const uint8_t*)hb_blob_get_data(mSVGData, &length);
 116           if (entry->mDocOffset > 0 && uint64_t(mHeader->mDocIndexOffset) +
 117                                                entry->mDocOffset +
 118                                                entry->mDocLength <=
 119                                            length) {
 120             return glyphDocsEntry
 121                 .Insert(MakeUnique<gfxSVGGlyphsDocument>(
 122                     data + mHeader->mDocIndexOffset + entry->mDocOffset,
 123                     entry->mDocLength, this))
 124                 .get();
 125           }
 126
 127           return nullptr;
 128         }
 129
 130         return glyphDocsEntry->get();
 131       });
 132 }
 133
 134 nsresult gfxSVGGlyphsDocument::SetupPresentation() {
 135   nsCOMPtr<nsICategoryManager> catMan =
 136       do_GetService(NS_CATEGORYMANAGER_CONTRACTID);
 137   nsCString contractId;
 138   nsresult rv = catMan->GetCategoryEntry("Gecko-Content-Viewers",
 139                                          "image/svg+xml", contractId);
 140   NS_ENSURE_SUCCESS(rv, rv);
 141
 142   nsCOMPtr<nsIDocumentLoaderFactory> docLoaderFactory =
 143       do_GetService(contractId.get());
 144   NS_ASSERTION(docLoaderFactory, "Couldn't get DocumentLoaderFactory");
 145
 146   nsCOMPtr<nsIContentViewer> viewer;
 147   rv = docLoaderFactory->CreateInstanceForDocument(nullptr, mDocument, nullptr,
 148                                                    getter_AddRefs(viewer));
 149   NS_ENSURE_SUCCESS(rv, rv);
 150
 151   rv = viewer->Init(nullptr, gfx::IntRect(0, 0, 1000, 1000), nullptr);
 152   if (NS_SUCCEEDED(rv)) {
 153     rv = viewer->Open(nullptr, nullptr);
 154     NS_ENSURE_SUCCESS(rv, rv);
 155   }
 156
 157   RefPtr<PresShell> presShell = viewer->GetPresShell();
 158   if (!presShell->DidInitialize()) {
 159     rv = presShell->Initialize();
 160     NS_ENSURE_SUCCESS(rv, rv);
 161   }
 162
 163   mDocument->FlushPendingNotifications(FlushType::Layout);
 164
 165   if (mDocument->HasAnimationController()) {
 166     mDocument->GetAnimationController()->Resume(SMILTimeContainer::PAUSE_IMAGE);
 167   }
 168   mDocument->ImageTracker()->SetAnimatingState(true);
 169
 170   mViewer = viewer;
 171   mPresShell = presShell;
 172   mPresShell->AddPostRefreshObserver(this);
 173
 174   return NS_OK;
 175 }
 176
 177 void gfxSVGGlyphsDocument::DidRefresh() { mOwner->DidRefresh(); }
 178
 179 /**
 180  * Walk the DOM tree to find all glyph elements and insert them into the lookup
 181  * table
 182  * @param aElem The element to search from
 183  */
 184 void gfxSVGGlyphsDocument::FindGlyphElements(Element* aElem) {
 185   for (nsIContent* child = aElem->GetLastChild(); child;
 186        child = child->GetPreviousSibling()) {
 187     if (!child->IsElement()) {
 188       continue;
 189     }
 190     FindGlyphElements(child->AsElement());
 191   }
 192
 193   InsertGlyphId(aElem);
 194 }
 195
 196 /**
 197  * If there exists an SVG glyph with the specified glyph id, render it and
 198  * return true If no such glyph exists, or in the case of an error return false
 199  * @param aContext The thebes aContext to draw to
 200  * @param aGlyphId The glyph id
 201  * @return true iff rendering succeeded
 202  */
 203 void gfxSVGGlyphs::RenderGlyph(gfxContext* aContext, uint32_t aGlyphId,
 204                                SVGContextPaint* aContextPaint) {
 205   gfxContextAutoSaveRestore aContextRestorer(aContext);
 206
 207   Element* glyph = mGlyphIdMap.Get(aGlyphId);
 208   MOZ_ASSERT(glyph, "No glyph element. Should check with HasSVGGlyph() first!");
 209
 210   AutoSetRestoreSVGContextPaint autoSetRestore(
 211       *aContextPaint, *glyph->OwnerDoc()->AsSVGDocument());
 212
 213   SVGUtils::PaintSVGGlyph(glyph, aContext);
 214 }
 215
 216 bool gfxSVGGlyphs::GetGlyphExtents(uint32_t aGlyphId,
 217                                    const gfxMatrix& aSVGToAppSpace,
 218                                    gfxRect* aResult) {
 219   Element* glyph = mGlyphIdMap.Get(aGlyphId);
 220   NS_ASSERTION(glyph,
 221                "No glyph element. Should check with HasSVGGlyph() first!");
 222
 223   return SVGUtils::GetSVGGlyphExtents(glyph, aSVGToAppSpace, aResult);
 224 }
 225
 226 Element* gfxSVGGlyphs::GetGlyphElement(uint32_t aGlyphId) {
 227   return mGlyphIdMap.LookupOrInsertWith(aGlyphId, [&] {
 228     Element* elem = nullptr;
 229     if (gfxSVGGlyphsDocument* set = FindOrCreateGlyphsDocument(aGlyphId)) {
 230       elem = set->GetGlyphElement(aGlyphId);
 231     }
 232     return elem;
 233   });
 234 }
 235
 236 bool gfxSVGGlyphs::HasSVGGlyph(uint32_t aGlyphId) {
 237   return !!GetGlyphElement(aGlyphId);
 238 }
 239
 240 size_t gfxSVGGlyphs::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
 241   // We don't include the size of mSVGData here, because (depending on the
 242   // font backend implementation) it will either wrap a block of data owned
 243   // by the system (and potentially shared), or a table that's in our font
 244   // table cache and therefore already counted.
 245   size_t result = aMallocSizeOf(this) +
 246                   mGlyphDocs.ShallowSizeOfExcludingThis(aMallocSizeOf) +
 247                   mGlyphIdMap.ShallowSizeOfExcludingThis(aMallocSizeOf);
 248   for (const auto& entry : mGlyphDocs.Values()) {
 249     result += entry->SizeOfIncludingThis(aMallocSizeOf);
 250   }
 251   return result;
 252 }
 253
 254 Element* gfxSVGGlyphsDocument::GetGlyphElement(uint32_t aGlyphId) {
 255   return mGlyphIdMap.Get(aGlyphId);
 256 }
 257
 258 gfxSVGGlyphsDocument::gfxSVGGlyphsDocument(const uint8_t* aBuffer,
 259                                            uint32_t aBufLen,
 260                                            gfxSVGGlyphs* aSVGGlyphs)
 261     : mOwner(aSVGGlyphs) {
 262   if (aBufLen >= 14 && aBuffer[0] == 31 && aBuffer[1] == 139) {
 263     // It's a gzip-compressed document; decompress it before parsing.
 264     // The original length (modulo 2^32) is found in the last 4 bytes
 265     // of the data, stored in little-endian format. We read it as
 266     // individual bytes to avoid possible alignment issues.
 267     // (Note that if the original length was >2^32, then origLen here
 268     // will be incorrect; but then the inflate() call will not return
 269     // Z_STREAM_END and we'll bail out safely.)
 270     size_t origLen = (size_t(aBuffer[aBufLen - 1]) << 24) +
 271                      (size_t(aBuffer[aBufLen - 2]) << 16) +
 272                      (size_t(aBuffer[aBufLen - 3]) << 8) +
 273                      size_t(aBuffer[aBufLen - 4]);
 274     AutoTArray<uint8_t, 4096> outBuf;
 275     if (outBuf.SetLength(origLen, mozilla::fallible)) {
 276       z_stream s = {0};
 277       s.next_in = const_cast<Byte*>(aBuffer);
 278       s.avail_in = aBufLen;
 279       s.next_out = outBuf.Elements();
 280       s.avail_out = outBuf.Length();
 281       // The magic number 16 here is the zlib flag to expect gzip format,
 282       // see http://www.zlib.net/manual.html#Advanced
 283       if (Z_OK == inflateInit2(&s, 16 + MAX_WBITS)) {
 284         int result = inflate(&s, Z_FINISH);
 285         if (Z_STREAM_END == result) {
 286           MOZ_ASSERT(size_t(s.next_out - outBuf.Elements()) == origLen);
 287           ParseDocument(outBuf.Elements(), outBuf.Length());
 288         } else {
 289           NS_WARNING("Failed to decompress SVG glyphs document");
 290         }
 291         inflateEnd(&s);
 292       }
 293     } else {
 294       NS_WARNING("Failed to allocate memory for SVG glyphs document");
 295     }
 296   } else {
 297     ParseDocument(aBuffer, aBufLen);
 298   }
 299
 300   if (!mDocument) {
 301     NS_WARNING("Could not parse SVG glyphs document");
 302     return;
 303   }
 304
 305   Element* root = mDocument->GetRootElement();
 306   if (!root) {
 307     NS_WARNING("Could not parse SVG glyphs document");
 308     return;
 309   }
 310
 311   nsresult rv = SetupPresentation();
 312   if (NS_FAILED(rv)) {
 313     NS_WARNING("Couldn't setup presentation for SVG glyphs document");
 314     return;
 315   }
 316
 317   FindGlyphElements(root);
 318 }
 319
 320 gfxSVGGlyphsDocument::~gfxSVGGlyphsDocument() {
 321   if (mDocument) {
 322     mDocument->OnPageHide(false, nullptr);
 323   }
 324   if (mPresShell) {
 325     mPresShell->RemovePostRefreshObserver(this);
 326   }
 327   if (mViewer) {
 328     mViewer->Close(nullptr);
 329     mViewer->Destroy();
 330   }
 331 }
 332
 333 static nsresult CreateBufferedStream(const uint8_t* aBuffer, uint32_t aBufLen,
 334                                      nsCOMPtr<nsIInputStream>& aResult) {
 335   nsCOMPtr<nsIInputStream> stream;
 336   nsresult rv = NS_NewByteInputStream(
 337       getter_AddRefs(stream),
 338       Span(reinterpret_cast<const char*>(aBuffer), aBufLen),
 339       NS_ASSIGNMENT_DEPEND);
 340   NS_ENSURE_SUCCESS(rv, rv);
 341
 342   nsCOMPtr<nsIInputStream> aBufferedStream;
 343   if (!NS_InputStreamIsBuffered(stream)) {
 344     rv = NS_NewBufferedInputStream(getter_AddRefs(aBufferedStream),
 345                                    stream.forget(), 4096);
 346     NS_ENSURE_SUCCESS(rv, rv);
 347     stream = aBufferedStream;
 348   }
 349
 350   aResult = stream;
 351
 352   return NS_OK;
 353 }
 354
 355 nsresult gfxSVGGlyphsDocument::ParseDocument(const uint8_t* aBuffer,
 356                                              uint32_t aBufLen) {
 357   // Mostly pulled from nsDOMParser::ParseFromStream
 358
 359   nsCOMPtr<nsIInputStream> stream;
 360   nsresult rv = CreateBufferedStream(aBuffer, aBufLen, stream);
 361   NS_ENSURE_SUCCESS(rv, rv);
 362
 363   nsCOMPtr<nsIURI> uri;
 364   mozilla::dom::FontTableURIProtocolHandler::GenerateURIString(
 365       mSVGGlyphsDocumentURI);
 366
 367   rv = NS_NewURI(getter_AddRefs(uri), mSVGGlyphsDocumentURI);
 368   NS_ENSURE_SUCCESS(rv, rv);
 369
 370   nsCOMPtr<nsIPrincipal> principal =
 371       NullPrincipal::CreateWithoutOriginAttributes();
 372
 373   RefPtr<Document> document;
 374   rv = NS_NewDOMDocument(getter_AddRefs(document),
 375                          u""_ns,   // aNamespaceURI
 376                          u""_ns,   // aQualifiedName
 377                          nullptr,  // aDoctype
 378                          uri, uri, principal,
 379                          false,    // aLoadedAsData
 380                          nullptr,  // aEventObject
 381                          DocumentFlavorSVG);
 382   NS_ENSURE_SUCCESS(rv, rv);
 383
 384   nsCOMPtr<nsIChannel> channel;
 385   rv = NS_NewInputStreamChannel(
 386       getter_AddRefs(channel), uri,
 387       nullptr,  // aStream
 388       principal, nsILoadInfo::SEC_FORCE_INHERIT_PRINCIPAL,
 389       nsIContentPolicy::TYPE_OTHER, SVG_CONTENT_TYPE, UTF8_CHARSET);
 390   NS_ENSURE_SUCCESS(rv, rv);
 391
 392   // Set this early because various decisions during page-load depend on it.
 393   document->SetIsBeingUsedAsImage();
 394   document->SetIsSVGGlyphsDocument();
 395   document->SetReadyStateInternal(Document::READYSTATE_UNINITIALIZED);
 396
 397   nsCOMPtr<nsIStreamListener> listener;
 398   rv = document->StartDocumentLoad("external-resource", channel,
 399                                    nullptr,  // aLoadGroup
 400                                    nullptr,  // aContainer
 401                                    getter_AddRefs(listener), true /* aReset */);
 402   if (NS_FAILED(rv) || !listener) {
 403     return NS_ERROR_FAILURE;
 404   }
 405
 406   rv = listener->OnStartRequest(channel);
 407   if (NS_FAILED(rv)) {
 408     channel->Cancel(rv);
 409   }
 410
 411   nsresult status;
 412   channel->GetStatus(&status);
 413   if (NS_SUCCEEDED(rv) && NS_SUCCEEDED(status)) {
 414     rv = listener->OnDataAvailable(channel, stream, 0, aBufLen);
 415     if (NS_FAILED(rv)) {
 416       channel->Cancel(rv);
 417     }
 418     channel->GetStatus(&status);
 419   }
 420
 421   rv = listener->OnStopRequest(channel, status);
 422   NS_ENSURE_SUCCESS(rv, NS_ERROR_FAILURE);
 423
 424   document.swap(mDocument);
 425
 426   return NS_OK;
 427 }
 428
 429 void gfxSVGGlyphsDocument::InsertGlyphId(Element* aGlyphElement) {
 430   nsAutoString glyphIdStr;
 431   static const uint32_t glyphPrefixLength = 5;
 432   // The maximum glyph ID is 65535 so the maximum length of the numeric part
 433   // is 5.
 434   if (!aGlyphElement->GetAttr(kNameSpaceID_None, nsGkAtoms::id, glyphIdStr) ||
 435       !StringBeginsWith(glyphIdStr, u"glyph"_ns) ||
 436       glyphIdStr.Length() > glyphPrefixLength + 5) {
 437     return;
 438   }
 439
 440   uint32_t id = 0;
 441   for (uint32_t i = glyphPrefixLength; i < glyphIdStr.Length(); ++i) {
 442     char16_t ch = glyphIdStr.CharAt(i);
 443     if (ch < '0' || ch > '9') {
 444       return;
 445     }
 446     if (ch == '0' && i == glyphPrefixLength) {
 447       return;
 448     }
 449     id = id * 10 + (ch - '0');
 450   }
 451
 452   mGlyphIdMap.InsertOrUpdate(id, aGlyphElement);
 453 }
 454
 455 size_t gfxSVGGlyphsDocument::SizeOfIncludingThis(
 456     mozilla::MallocSizeOf aMallocSizeOf) const {
 457   return aMallocSizeOf(this) +
 458          mGlyphIdMap.ShallowSizeOfExcludingThis(aMallocSizeOf) +
 459          mSVGGlyphsDocumentURI.SizeOfExcludingThisIfUnshared(aMallocSizeOf);
 460 }