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SharedFontList.cpp
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SharedFontList.cpp
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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "SharedFontList-impl.h"
#include "gfxPlatformFontList.h"
#include "gfxFontUtils.h"
#include "gfxFont.h"
#include "nsReadableUtils.h"
#include "prerror.h"
#include "mozilla/dom/ContentChild.h"
#include "mozilla/Logging.h"
#define LOG_FONTLIST(args) \
MOZ_LOG(gfxPlatform::GetLog(eGfxLog_fontlist), LogLevel::Debug, args)
#define LOG_FONTLIST_ENABLED() \
MOZ_LOG_TEST(gfxPlatform::GetLog(eGfxLog_fontlist), LogLevel::Debug)
namespace mozilla {
namespace fontlist {
static double WSSDistance(const Face* aFace, const gfxFontStyle& aStyle) {
double stretchDist = StretchDistance(aFace->mStretch, aStyle.stretch);
double styleDist = StyleDistance(aFace->mStyle, aStyle.style);
double weightDist = WeightDistance(aFace->mWeight, aStyle.weight);
// Sanity-check that the distances are within the expected range
// (update if implementation of the distance functions is changed).
MOZ_ASSERT(stretchDist >= 0.0 && stretchDist <= 2000.0);
MOZ_ASSERT(styleDist >= 0.0 && styleDist <= 500.0);
MOZ_ASSERT(weightDist >= 0.0 && weightDist <= 1600.0);
// weight/style/stretch priority: stretch >> style >> weight
// so we multiply the stretch and style values to make them dominate
// the result
return stretchDist * 1.0e8 + styleDist * 1.0e4 + weightDist;
}
void* Pointer::ToPtr(FontList* aFontList) const {
if (IsNull()) {
return nullptr;
}
uint32_t block = Block();
// If the Pointer refers to a block we have not yet mapped in this process,
// we first need to retrieve new block handle(s) from the parent and update
// our mBlocks list.
if (block >= aFontList->mBlocks.Length()) {
if (XRE_IsParentProcess()) {
// Shouldn't happen! A content process tried to pass a bad Pointer?
return nullptr;
}
// UpdateShmBlocks can fail, if the parent has replaced the font list with
// a new generation. In that case we just return null, and whatever font
// the content process was trying to use will appear unusable for now. It's
// about to receive a notification of the new font list anyhow, at which
// point it will flush its caches and reflow everything, so the temporary
// failure of this font will be forgotten.
if (!aFontList->UpdateShmBlocks()) {
return nullptr;
}
MOZ_ASSERT(block < aFontList->mBlocks.Length());
}
return static_cast<char*>(aFontList->mBlocks[block]->mAddr) + Offset();
}
void String::Assign(const nsACString& aString, FontList* aList) {
// We only assign to previously-empty strings; they are never modified
// after initial assignment.
MOZ_ASSERT(mPointer.IsNull());
mLength = aString.Length();
mPointer = aList->Alloc(mLength + 1);
char* p = static_cast<char*>(mPointer.ToPtr(aList));
std::memcpy(p, aString.BeginReading(), mLength);
p[mLength] = '\0';
}
Family::Family(FontList* aList, const InitData& aData)
: mFaceCount(0),
mKey(aList, aData.mKey),
mName(aList, aData.mName),
mCharacterMap(Pointer::Null()),
mFaces(Pointer::Null()),
mIndex(aData.mIndex),
mIsHidden(aData.mHidden),
mIsBadUnderlineFamily(aData.mBadUnderline),
mIsForceClassic(aData.mForceClassic),
mIsSimple(false) {
MOZ_ASSERT(aData.mIndex <= 0x7fffffffu);
mIndex = aData.mIndex | (aData.mBundled ? 0x80000000u : 0u);
}
void Face::SetCharacterMap(FontList* aList, const gfxSparseBitSet* aCharMap) {
if (!XRE_IsParentProcess()) {
Pointer ptr = aList->ToSharedPointer(this);
dom::ContentChild::GetSingleton()->SendSetCharacterMap(
aList->GetGeneration(), ptr, *aCharMap);
return;
}
auto pfl = gfxPlatformFontList::PlatformFontList();
mCharacterMap = pfl->GetShmemCharMap(aCharMap);
}
void Family::AddFaces(FontList* aList, const nsTArray<Face::InitData>& aFaces) {
MOZ_ASSERT(XRE_IsParentProcess());
if (mFaceCount > 0) {
// Already initialized!
return;
}
uint32_t count = aFaces.Length();
bool isSimple = false;
// A family is "simple" (i.e. simplified style selection may be used instead
// of the full CSS font-matching algorithm) if there is at maximum one normal,
// bold, italic, and bold-italic face; in this case, they are stored at known
// positions in the mFaces array.
const Face::InitData* slots[4] = {nullptr, nullptr, nullptr, nullptr};
if (count >= 2 && count <= 4) {
// Check if this can be treated as a "simple" family
isSimple = true;
for (const auto& f : aFaces) {
if (!f.mWeight.IsSingle() || !f.mStretch.IsSingle() ||
!f.mStyle.IsSingle()) {
isSimple = false;
break;
}
if (!f.mStretch.Min().IsNormal()) {
isSimple = false;
break;
}
// Figure out which slot (0-3) this face belongs in
size_t slot = 0;
static_assert((kBoldMask | kItalicMask) == 0b11, "bad bold/italic bits");
if (f.mWeight.Min().IsBold()) {
slot |= kBoldMask;
}
if (f.mStyle.Min().IsItalic() || f.mStyle.Min().IsOblique()) {
slot |= kItalicMask;
}
if (slots[slot]) {
// More than one face mapped to the same slot - not a simple family!
isSimple = false;
break;
}
slots[slot] = &f;
}
if (isSimple) {
// Ensure all 4 slots will exist, even if some are empty.
count = 4;
}
}
// Allocate space for the face records, and initialize them.
// coverity[suspicious_sizeof]
Pointer p = aList->Alloc(count * sizeof(Pointer));
auto facePtrs = static_cast<Pointer*>(p.ToPtr(aList));
for (size_t i = 0; i < count; i++) {
if (isSimple && !slots[i]) {
facePtrs[i] = Pointer::Null();
} else {
Pointer fp = aList->Alloc(sizeof(Face));
auto face = static_cast<Face*>(fp.ToPtr(aList));
(void)new (face) Face(aList, isSimple ? *slots[i] : aFaces[i]);
facePtrs[i] = fp;
}
}
mIsSimple = isSimple;
mFaces = p;
mFaceCount.store(count);
if (LOG_FONTLIST_ENABLED()) {
const nsCString& fam = DisplayName().AsString(aList);
for (unsigned j = 0; j < aFaces.Length(); j++) {
nsAutoCString weight, style, stretch;
aFaces[j].mWeight.ToString(weight);
aFaces[j].mStyle.ToString(style);
aFaces[j].mStretch.ToString(stretch);
LOG_FONTLIST(
("(shared-fontlist) family (%s) added face (%s) index %u, weight "
"%s, style %s, stretch %s",
fam.get(), aFaces[j].mDescriptor.get(), aFaces[j].mIndex,
weight.get(), style.get(), stretch.get()));
}
}
}
void Family::FindAllFacesForStyle(FontList* aList, const gfxFontStyle& aStyle,
nsTArray<Face*>& aFaceList,
bool aIgnoreSizeTolerance) const {
MOZ_ASSERT(aFaceList.IsEmpty());
if (!IsInitialized()) {
return;
}
Pointer* facePtrs = Faces(aList);
if (!facePtrs) {
return;
}
// If the family has only one face, we simply return it; no further
// checking needed.
if (NumFaces() == 1) {
MOZ_ASSERT(!facePtrs[0].IsNull());
aFaceList.AppendElement(static_cast<Face*>(facePtrs[0].ToPtr(aList)));
return;
}
// Most families are "simple", having just Regular/Bold/Italic/BoldItalic,
// or some subset of these. In this case, we have exactly 4 entries in
// mAvailableFonts, stored in the above order; note that some of the entries
// may be nullptr. We can then pick the required entry based on whether the
// request is for bold or non-bold, italic or non-italic, without running the
// more complex matching algorithm used for larger families with many weights
// and/or widths.
if (mIsSimple) {
// Family has no more than the "standard" 4 faces, at fixed indexes;
// calculate which one we want.
// Note that we cannot simply return it as not all 4 faces are necessarily
// present.
bool wantBold = aStyle.weight >= FontWeight(600);
bool wantItalic = !aStyle.style.IsNormal();
uint8_t faceIndex =
(wantItalic ? kItalicMask : 0) | (wantBold ? kBoldMask : 0);
// if the desired style is available, return it directly
Face* face = static_cast<Face*>(facePtrs[faceIndex].ToPtr(aList));
if (face && face->HasValidDescriptor()) {
aFaceList.AppendElement(face);
return;
}
// order to check fallback faces in a simple family, depending on requested
// style
static const uint8_t simpleFallbacks[4][3] = {
{kBoldFaceIndex, kItalicFaceIndex,
kBoldItalicFaceIndex}, // fallback sequence for Regular
{kRegularFaceIndex, kBoldItalicFaceIndex, kItalicFaceIndex}, // Bold
{kBoldItalicFaceIndex, kRegularFaceIndex, kBoldFaceIndex}, // Italic
{kItalicFaceIndex, kBoldFaceIndex, kRegularFaceIndex} // BoldItalic
};
const uint8_t* order = simpleFallbacks[faceIndex];
for (uint8_t trial = 0; trial < 3; ++trial) {
// check remaining faces in order of preference to find the first that
// actually exists
face = static_cast<Face*>(facePtrs[order[trial]].ToPtr(aList));
if (face && face->HasValidDescriptor()) {
aFaceList.AppendElement(face);
return;
}
}
// this can't happen unless we have totally broken the font-list manager!
MOZ_ASSERT_UNREACHABLE("no face found in simple font family!");
}
// Pick the font(s) that are closest to the desired weight, style, and
// stretch. Iterate over all fonts, measuring the weight/style distance.
// Because of unicode-range values, there may be more than one font for a
// given but the 99% use case is only a single font entry per
// weight/style/stretch distance value. To optimize this, only add entries
// to the matched font array when another entry already has the same
// weight/style/stretch distance and add the last matched font entry. For
// normal platform fonts with a single font entry for each
// weight/style/stretch combination, only the last matched font entry will
// be added.
double minDistance = INFINITY;
Face* matched = nullptr;
for (uint32_t i = 0; i < NumFaces(); i++) {
Face* face = static_cast<Face*>(facePtrs[i].ToPtr(aList));
// weight/style/stretch priority: stretch >> style >> weight
double distance = WSSDistance(face, aStyle);
if (distance < minDistance) {
matched = face;
if (!aFaceList.IsEmpty()) {
aFaceList.Clear();
}
minDistance = distance;
} else if (distance == minDistance) {
if (matched) {
aFaceList.AppendElement(matched);
}
matched = face;
}
}
MOZ_ASSERT(matched, "didn't match a font within a family");
if (matched) {
aFaceList.AppendElement(matched);
}
}
Face* Family::FindFaceForStyle(FontList* aList, const gfxFontStyle& aStyle,
bool aIgnoreSizeTolerance) const {
AutoTArray<Face*, 4> faces;
FindAllFacesForStyle(aList, aStyle, faces, aIgnoreSizeTolerance);
return faces.IsEmpty() ? nullptr : faces[0];
}
void Family::SearchAllFontsForChar(FontList* aList,
GlobalFontMatch* aMatchData) {
const SharedBitSet* charmap =
static_cast<const SharedBitSet*>(mCharacterMap.ToPtr(aList));
if (charmap && !charmap->test(aMatchData->mCh)) {
return;
}
if (!IsInitialized()) {
if (!gfxPlatformFontList::PlatformFontList()->InitializeFamily(this)) {
return;
}
}
uint32_t numFaces = NumFaces();
uint32_t charMapsLoaded = 0; // number of faces whose charmap is loaded
Pointer* facePtrs = Faces(aList);
if (!facePtrs) {
return;
}
for (uint32_t i = 0; i < numFaces; i++) {
Face* face = static_cast<Face*>(facePtrs[i].ToPtr(aList));
if (!face) {
continue;
}
MOZ_ASSERT(face->HasValidDescriptor());
// Get the face's character map, if available (may be null!)
charmap =
static_cast<const SharedBitSet*>(face->mCharacterMap.ToPtr(aList));
if (charmap) {
++charMapsLoaded;
}
// Check style distance if the char is supported, or if charmap not known
// (so that we don't trigger cmap-loading for faces that would be a worse
// match than what we've already found).
if (!charmap || charmap->test(aMatchData->mCh)) {
double distance = WSSDistance(face, aMatchData->mStyle);
if (distance < aMatchData->mMatchDistance) {
// It's a better style match: get a fontEntry, and if we haven't
// already checked character coverage, do it now (note that
// HasCharacter() will trigger loading the fontEntry's cmap, if
// needed).
RefPtr<gfxFontEntry> fe =
gfxPlatformFontList::PlatformFontList()->GetOrCreateFontEntry(face,
this);
if (!fe) {
continue;
}
if (!charmap && !fe->HasCharacter(aMatchData->mCh)) {
continue;
}
aMatchData->mBestMatch = fe;
aMatchData->mMatchDistance = distance;
aMatchData->mMatchedSharedFamily = this;
}
}
}
if (mCharacterMap.IsNull() && charMapsLoaded == numFaces) {
SetupFamilyCharMap(aList);
}
}
void Family::SetFacePtrs(FontList* aList, nsTArray<Pointer>& aFaces) {
if (aFaces.Length() >= 2 && aFaces.Length() <= 4) {
// Check whether the faces meet the criteria for a "simple" family: no more
// than one each of Regular, Bold, Italic, BoldItalic styles. If so, store
// them at the appropriate slots in mFaces and set the mIsSimple flag to
// accelerate font-matching.
bool isSimple = true;
Pointer slots[4] = {Pointer::Null(), Pointer::Null(), Pointer::Null(),
Pointer::Null()};
for (const Pointer& fp : aFaces) {
const Face* f = static_cast<const Face*>(fp.ToPtr(aList));
if (!f->mWeight.IsSingle() || !f->mStyle.IsSingle() ||
!f->mStretch.IsSingle()) {
isSimple = false;
break;
}
if (!f->mStretch.Min().IsNormal()) {
isSimple = false;
break;
}
size_t slot = 0;
if (f->mWeight.Min().IsBold()) {
slot |= kBoldMask;
}
if (f->mStyle.Min().IsItalic() || f->mStyle.Min().IsOblique()) {
slot |= kItalicMask;
}
if (!slots[slot].IsNull()) {
isSimple = false;
break;
}
slots[slot] = fp;
}
if (isSimple) {
size_t size = 4 * sizeof(Pointer);
mFaces = aList->Alloc(size);
memcpy(mFaces.ToPtr(aList), slots, size);
mFaceCount.store(4);
mIsSimple = true;
return;
}
}
size_t size = aFaces.Length() * sizeof(Pointer);
mFaces = aList->Alloc(size);
memcpy(mFaces.ToPtr(aList), aFaces.Elements(), size);
mFaceCount.store(aFaces.Length());
}
void Family::SetupFamilyCharMap(FontList* aList) {
// Set the character map of the family to the union of all the face cmaps,
// to allow font fallback searches to more rapidly reject the family.
if (!XRE_IsParentProcess()) {
// |this| could be a Family record in either the Families() or Aliases()
// arrays
dom::ContentChild::GetSingleton()->SendSetupFamilyCharMap(
aList->GetGeneration(), aList->ToSharedPointer(this));
return;
}
gfxSparseBitSet familyMap;
Pointer firstMapShmPointer;
SharedBitSet* firstMap = nullptr;
bool merged = false;
Pointer* faces = Faces(aList);
if (!faces) {
return;
}
for (size_t i = 0; i < NumFaces(); i++) {
auto f = static_cast<Face*>(faces[i].ToPtr(aList));
if (!f) {
continue;
}
auto faceMap = static_cast<SharedBitSet*>(f->mCharacterMap.ToPtr(aList));
MOZ_ASSERT(faceMap);
if (!firstMap) {
firstMap = faceMap;
firstMapShmPointer = f->mCharacterMap;
} else if (faceMap != firstMap) {
if (!merged) {
familyMap.Union(*firstMap);
merged = true;
}
familyMap.Union(*faceMap);
}
}
if (merged) {
mCharacterMap =
gfxPlatformFontList::PlatformFontList()->GetShmemCharMap(&familyMap);
} else {
mCharacterMap = firstMapShmPointer;
}
}
FontList::FontList(uint32_t aGeneration) {
if (XRE_IsParentProcess()) {
// Create the initial shared block, and initialize Header
if (AppendShmBlock()) {
Header& header = GetHeader();
header.mAllocated.store(sizeof(Header));
header.mGeneration = aGeneration;
header.mFamilyCount = 0;
header.mBlockCount.store(1);
header.mAliasCount.store(0);
header.mLocalFaceCount.store(0);
header.mFamilies = Pointer::Null();
header.mAliases = Pointer::Null();
header.mLocalFaces = Pointer::Null();
} else {
MOZ_CRASH("parent: failed to initialize FontList");
}
} else {
for (unsigned retryCount = 0; retryCount < 3; ++retryCount) {
if (UpdateShmBlocks()) {
return;
}
// The only reason for UpdateShmBlocks to fail is if the parent recreated
// the list after we read its first block, but before we finished getting
// them all, and so the generation check failed on a subsequent request.
// Discarding whatever we've got and retrying should get us a new,
// consistent set of memory blocks in this case. If this doesn't work
// after a couple of retries, bail out.
DetachShmBlocks();
}
NS_WARNING("child: failed to initialize shared FontList");
}
}
FontList::~FontList() { DetachShmBlocks(); }
bool FontList::AppendShmBlock() {
MOZ_ASSERT(XRE_IsParentProcess());
ipc::SharedMemoryBasic* newShm = new ipc::SharedMemoryBasic();
if (!newShm->Create(SHM_BLOCK_SIZE)) {
MOZ_CRASH("failed to create shared memory");
return false;
}
if (!newShm->Map(SHM_BLOCK_SIZE)) {
MOZ_CRASH("failed to map shared memory");
}
char* addr = static_cast<char*>(newShm->memory());
if (!addr) {
MOZ_CRASH("null shared memory?");
return false;
}
ShmBlock* block = new ShmBlock(newShm, addr);
// Allocate space for the Allocated() header field present in all blocks
block->Allocated().store(4);
mBlocks.AppendElement(block);
GetHeader().mBlockCount.store(mBlocks.Length());
return true;
}
void FontList::DetachShmBlocks() {
for (auto& i : mBlocks) {
i->mShmem = nullptr;
}
mBlocks.SetLength(0);
}
FontList::ShmBlock* FontList::GetBlockFromParent(uint32_t aIndex) {
MOZ_ASSERT(!XRE_IsParentProcess());
// If we have no existing blocks, we don't want a generation check yet;
// the header in the first block will define the generation of this list
uint32_t generation = aIndex == 0 ? 0 : GetGeneration();
ipc::SharedMemoryBasic::Handle handle = ipc::SharedMemoryBasic::NULLHandle();
if (!dom::ContentChild::GetSingleton()->SendGetFontListShmBlock(
generation, aIndex, &handle)) {
return nullptr;
}
RefPtr<ipc::SharedMemoryBasic> newShm = new ipc::SharedMemoryBasic();
if (!newShm->IsHandleValid(handle)) {
return nullptr;
}
if (!newShm->SetHandle(handle,
mozilla::ipc::SharedMemoryBasic::RightsReadOnly)) {
MOZ_CRASH("failed to set shm handle");
}
if (!newShm->Map(SHM_BLOCK_SIZE)) {
MOZ_CRASH("failed to map shared memory");
}
char* addr = static_cast<char*>(newShm->memory());
if (!addr) {
MOZ_CRASH("null shared memory?");
}
return new ShmBlock(newShm, addr);
}
bool FontList::UpdateShmBlocks() {
MOZ_ASSERT(!XRE_IsParentProcess());
while (!mBlocks.Length() || mBlocks.Length() < GetHeader().mBlockCount) {
ShmBlock* newBlock = GetBlockFromParent(mBlocks.Length());
if (!newBlock) {
return false;
}
mBlocks.AppendElement(newBlock);
}
return true;
}
// The block size MUST be sufficient to allocate the largest possible
// SharedBitSet in a single contiguous block, following its own
// Allocated() field.
static_assert(FontList::SHM_BLOCK_SIZE >= 4 + SharedBitSet::kMaxSize,
"may not be able to allocate a SharedBitSet");
Pointer FontList::Alloc(uint32_t aSize) {
// Only the parent process does allocation.
MOZ_ASSERT(XRE_IsParentProcess());
// 4-byte alignment is good enough for anything we allocate in the font list,
// as our "Pointer" (block index/offset) is a 32-bit value even on x64.
auto align = [](uint32_t aSize) -> size_t { return (aSize + 3u) & ~3u; };
// There's a limit to the size of object we can allocate: the block size,
// minus the 4-byte mAllocated header field at the start of the block.
MOZ_DIAGNOSTIC_ASSERT(aSize <= SHM_BLOCK_SIZE - 4);
aSize = align(aSize);
int32_t blockIndex;
uint32_t curAlloc;
while (true) {
// Try to allocate in the most recently added block first, as this is
// highly likely to succeed; if not, try earlier blocks (to fill gaps).
const int32_t blockCount = mBlocks.Length();
for (blockIndex = blockCount - 1; blockIndex >= 0; --blockIndex) {
curAlloc = mBlocks[blockIndex]->Allocated();
if (SHM_BLOCK_SIZE - curAlloc >= aSize) {
break;
}
}
if (blockIndex < 0) {
// Couldn't find enough space: create a new block, and retry.
if (!AppendShmBlock()) {
return Pointer::Null();
}
continue; // retry; this will check the newly-added block first,
// which must succeed because it's empty
}
// We've found a block; allocate space from it, and return
mBlocks[blockIndex]->Allocated() = curAlloc + aSize;
break;
}
return Pointer(blockIndex, curAlloc);
}
void FontList::SetFamilyNames(const nsTArray<Family::InitData>& aFamilies) {
// Only the parent process should ever assign the list of families.
MOZ_ASSERT(XRE_IsParentProcess());
Header& header = GetHeader();
MOZ_ASSERT(!header.mFamilyCount);
size_t count = aFamilies.Length();
header.mFamilies = Alloc(count * sizeof(Family));
if (header.mFamilies.IsNull()) {
return;
}
Family* families = static_cast<Family*>(header.mFamilies.ToPtr(this));
for (size_t i = 0; i < count; i++) {
(void)new (&families[i]) Family(this, aFamilies[i]);
LOG_FONTLIST(("(shared-fontlist) family %u (%s)", (unsigned)i,
aFamilies[i].mName.get()));
}
header.mFamilyCount = count;
}
void FontList::SetAliases(
nsClassHashtable<nsCStringHashKey, AliasData>& aAliasTable) {
MOZ_ASSERT(XRE_IsParentProcess());
Header& header = GetHeader();
// Build an array of Family::InitData records based on the entries in
// aAliasTable, then sort them and store into the fontlist.
nsTArray<Family::InitData> aliasArray;
aliasArray.SetCapacity(aAliasTable.Count());
for (auto i = aAliasTable.Iter(); !i.Done(); i.Next()) {
aliasArray.AppendElement(Family::InitData(
i.Key(), i.Key(), i.Data()->mIndex, i.Data()->mHidden,
i.Data()->mBundled, i.Data()->mBadUnderline, i.Data()->mForceClassic));
}
aliasArray.Sort();
size_t count = aliasArray.Length();
if (count < header.mAliasCount) {
// This shouldn't happen, but handle it safely by just bailing out.
NS_WARNING("cannot reduce number of aliases");
return;
}
fontlist::Pointer ptr = Alloc(count * sizeof(Family));
Family* aliases = static_cast<Family*>(ptr.ToPtr(this));
for (size_t i = 0; i < count; i++) {
(void)new (&aliases[i]) Family(this, aliasArray[i]);
LOG_FONTLIST(("(shared-fontlist) alias family %u (%s)", (unsigned)i,
aliasArray[i].mName.get()));
aliases[i].SetFacePtrs(this, aAliasTable.Get(aliasArray[i].mName)->mFaces);
if (LOG_FONTLIST_ENABLED()) {
const auto& faces = aAliasTable.Get(aliasArray[i].mName)->mFaces;
for (unsigned j = 0; j < faces.Length(); j++) {
auto face = static_cast<const fontlist::Face*>(faces[j].ToPtr(this));
const nsCString& desc = face->mDescriptor.AsString(this);
nsAutoCString weight, style, stretch;
face->mWeight.ToString(weight);
face->mStyle.ToString(style);
face->mStretch.ToString(stretch);
LOG_FONTLIST(
("(shared-fontlist) face (%s) index %u, weight %s, style %s, "
"stretch %s",
desc.get(), face->mIndex, weight.get(), style.get(),
stretch.get()));
}
}
}
// Set the pointer before the count, so that any other process trying to read
// will not risk out-of-bounds access to the array.
header.mAliases = ptr;
header.mAliasCount.store(count);
}
void FontList::SetLocalNames(
nsDataHashtable<nsCStringHashKey, LocalFaceRec::InitData>&
aLocalNameTable) {
MOZ_ASSERT(XRE_IsParentProcess());
Header& header = GetHeader();
if (header.mLocalFaceCount > 0) {
return; // already been done!
}
nsTArray<nsCString> faceArray;
faceArray.SetCapacity(aLocalNameTable.Count());
for (auto i = aLocalNameTable.Iter(); !i.Done(); i.Next()) {
faceArray.AppendElement(i.Key());
}
faceArray.Sort();
size_t count = faceArray.Length();
Family* families = Families();
fontlist::Pointer ptr = Alloc(count * sizeof(LocalFaceRec));
LocalFaceRec* faces = static_cast<LocalFaceRec*>(ptr.ToPtr(this));
for (size_t i = 0; i < count; i++) {
(void)new (&faces[i]) LocalFaceRec();
const auto& rec = aLocalNameTable.Get(faceArray[i]);
faces[i].mKey.Assign(faceArray[i], this);
faces[i].mFamilyIndex = FindFamily(rec.mFamilyName) - families;
faces[i].mFaceIndex = rec.mFaceIndex;
}
header.mLocalFaces = ptr;
header.mLocalFaceCount.store(count);
}
Family* FontList::FindFamily(const nsCString& aName) {
struct FamilyNameComparator {
FamilyNameComparator(FontList* aList, const nsCString& aTarget)
: mList(aList), mTarget(aTarget) {}
int operator()(const Family& aVal) const {
return mTarget.Compare(aVal.Key().BeginReading(mList));
}
private:
FontList* mList;
const nsCString& mTarget;
};
Header& header = GetHeader();
Family* families = Families();
size_t match;
if (BinarySearchIf(families, 0, header.mFamilyCount,
FamilyNameComparator(this, aName), &match)) {
return &families[match];
}
if (header.mAliasCount) {
families = AliasFamilies();
size_t match;
if (BinarySearchIf(families, 0, header.mAliasCount,
FamilyNameComparator(this, aName), &match)) {
return &families[match];
}
}
#ifdef XP_WIN
// For Windows only, because of how DWrite munges font family names in some
// cases (see
// https://msdnshared.blob.core.windows.net/media/MSDNBlogsFS/prod.evol.blogs.msdn.com/CommunityServer.Components.PostAttachments/00/02/24/90/36/WPF%20Font%20Selection%20Model.pdf
// and discussion on the OpenType list), try stripping any known "regular"
// style name from the end of the requested family name.
// After the deferred font loader has finished, this is no longer needed as
// the "real" family names will have been found in AliasFamilies() above.
if (aName.Contains(' ')) {
auto pfl = gfxPlatformFontList::PlatformFontList();
if (header.mAliasCount) {
// Aliases have been fully loaded by the parent process, so just discard
// any stray mAliasTable and mLocalNameTable entries from earlier calls
// to this code, and return.
pfl->mAliasTable.Clear();
pfl->mLocalNameTable.Clear();
return nullptr;
}
const nsLiteralCString kStyleSuffixes[] = {
nsLiteralCString(" book"), nsLiteralCString(" medium"),
nsLiteralCString(" normal"), nsLiteralCString(" regular"),
nsLiteralCString(" roman"), nsLiteralCString(" upright")};
for (const auto& styleName : kStyleSuffixes) {
if (StringEndsWith(aName, styleName)) {
// See if we have a known family that matches the "base" family name
// with trailing style-name element stripped off.
nsAutoCString strippedName(aName.BeginReading(),
aName.Length() - styleName.Length());
families = Families();
if (BinarySearchIf(families, 0, header.mFamilyCount,
FamilyNameComparator(this, strippedName), &match)) {
// If so, this may be a possible family to satisfy the search; check
// if the extended family name was actually found as an alternate
// (either it's already in mAliasTable, or it gets added there when
// we call ReadFaceNamesForFamily on this candidate).
Family* candidateFamily = &families[match];
if (pfl->mAliasTable.Lookup(aName)) {
return candidateFamily;
}
// Note that ReadFaceNamesForFamily may store entries in mAliasTable
// (and mLocalNameTable), but if this is happening in a content
// process (which is the common case) those entries will not be saved
// into the shared font list; they're just used here until the "real"
// alias list is ready, then discarded.
pfl->ReadFaceNamesForFamily(candidateFamily, false);
if (pfl->mAliasTable.Lookup(aName)) {
return candidateFamily;
}
}
break;
}
}
}
#endif
return nullptr;
}
LocalFaceRec* FontList::FindLocalFace(const nsCString& aName) {
struct FaceNameComparator {
FaceNameComparator(FontList* aList, const nsCString& aTarget)
: mList(aList), mTarget(aTarget) {}
int operator()(const LocalFaceRec& aVal) const {
return mTarget.Compare(aVal.mKey.BeginReading(mList));
}
private:
FontList* mList;
const nsCString& mTarget;
};
Header& header = GetHeader();
LocalFaceRec* faces = LocalFaces();
size_t match;
if (BinarySearchIf(faces, 0, header.mLocalFaceCount,
FaceNameComparator(this, aName), &match)) {
return &faces[match];
}
return nullptr;
}
void FontList::SearchForLocalFace(const nsACString& aName, Family** aFamily,
Face** aFace) {
Header& header = GetHeader();
MOZ_ASSERT(header.mLocalFaceCount == 0,
"do not use when local face names are already set up!");
LOG_FONTLIST(
("(shared-fontlist) local face search for (%s)", aName.BeginReading()));
char initial = aName[0];
Family* families = Families();
for (uint32_t i = 0; i < header.mFamilyCount; i++) {
Family* family = &families[i];
if (family->Key().AsString(this)[0] != initial) {
continue;
}
LOG_FONTLIST(("(shared-fontlist) checking family (%s)",
family->Key().AsString(this).BeginReading()));
if (!family->IsInitialized()) {
if (!gfxPlatformFontList::PlatformFontList()->InitializeFamily(family)) {
continue;
}
}
Pointer* faces = family->Faces(this);
for (uint32_t j = 0; j < family->NumFaces(); j++) {
Face* face = static_cast<Face*>(faces[j].ToPtr(this));
if (!face) {
continue;
}
nsAutoCString psname, fullname;
if (gfxPlatformFontList::PlatformFontList()->ReadFaceNames(
family, face, psname, fullname)) {
LOG_FONTLIST(("(shared-fontlist) read psname (%s) fullname (%s)",
psname.get(), fullname.get()));
ToLowerCase(psname);
ToLowerCase(fullname);
if (aName == psname || aName == fullname) {
*aFamily = family;
*aFace = face;
return;
}
}
}
}
}
Pointer FontList::ToSharedPointer(const void* aPtr) {
const char* p = (const char*)aPtr;
const uint32_t blockCount = mBlocks.Length();
for (uint32_t i = 0; i < blockCount; ++i) {
const char* blockAddr = (const char*)mBlocks[i]->mAddr;
if (p >= blockAddr && p < blockAddr + SHM_BLOCK_SIZE) {
return Pointer(i, p - blockAddr);
}
}
MOZ_ASSERT_UNREACHABLE("invalid shared-memory pointer");
return Pointer::Null();
}
} // namespace fontlist
} // namespace mozilla