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// Copyright 2016 The PDFium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
#include "core/fpdfapi/font/cpdf_simplefont.h"
#include <algorithm>
#include <iterator>
#include <utility>
#include "constants/font_encodings.h"
#include "core/fpdfapi/parser/cpdf_array.h"
#include "core/fpdfapi/parser/cpdf_dictionary.h"
#include "core/fpdfapi/parser/cpdf_name.h"
#include "core/fxcrt/fx_codepage.h"
#include "core/fxge/freetype/fx_freetype.h"
#include "core/fxge/fx_font.h"
#include "third_party/base/numerics/safe_math.h"
namespace {
void GetPredefinedEncoding(const ByteString& value, FontEncoding* basemap) {
if (value == pdfium::font_encodings::kWinAnsiEncoding)
*basemap = FontEncoding::kWinAnsi;
else if (value == pdfium::font_encodings::kMacRomanEncoding)
*basemap = FontEncoding::kMacRoman;
else if (value == pdfium::font_encodings::kMacExpertEncoding)
*basemap = FontEncoding::kMacExpert;
else if (value == pdfium::font_encodings::kPDFDocEncoding)
*basemap = FontEncoding::kPdfDoc;
}
} // namespace
CPDF_SimpleFont::CPDF_SimpleFont(CPDF_Document* pDocument,
RetainPtr<CPDF_Dictionary> pFontDict)
: CPDF_Font(pDocument, std::move(pFontDict)) {
memset(m_CharWidth, 0xff, sizeof(m_CharWidth));
memset(m_GlyphIndex, 0xff, sizeof(m_GlyphIndex));
for (size_t i = 0; i < std::size(m_CharBBox); ++i)
m_CharBBox[i] = FX_RECT(-1, -1, -1, -1);
}
CPDF_SimpleFont::~CPDF_SimpleFont() = default;
int CPDF_SimpleFont::GlyphFromCharCode(uint32_t charcode, bool* pVertGlyph) {
if (pVertGlyph)
*pVertGlyph = false;
if (charcode > 0xff)
return -1;
int index = m_GlyphIndex[charcode];
if (index == 0xffff)
return -1;
return index;
}
void CPDF_SimpleFont::LoadCharMetrics(int charcode) {
if (!m_Font.GetFaceRec())
return;
if (charcode < 0 || charcode > 0xff) {
return;
}
int glyph_index = m_GlyphIndex[charcode];
if (glyph_index == 0xffff) {
if (!m_pFontFile && charcode != 32) {
LoadCharMetrics(32);
m_CharBBox[charcode] = m_CharBBox[32];
if (m_bUseFontWidth) {
m_CharWidth[charcode] = m_CharWidth[32];
}
}
return;
}
FXFT_FaceRec* face = m_Font.GetFaceRec();
int err =
FT_Load_Glyph(face, glyph_index,
FT_LOAD_NO_SCALE | FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH);
if (err)
return;
FT_Pos iHoriBearingX = FXFT_Get_Glyph_HoriBearingX(face);
FT_Pos iHoriBearingY = FXFT_Get_Glyph_HoriBearingY(face);
m_CharBBox[charcode] =
FX_RECT(TT2PDF(iHoriBearingX, face), TT2PDF(iHoriBearingY, face),
TT2PDF(iHoriBearingX + FXFT_Get_Glyph_Width(face), face),
TT2PDF(iHoriBearingY - FXFT_Get_Glyph_Height(face), face));
if (m_bUseFontWidth) {
int TT_Width = TT2PDF(FXFT_Get_Glyph_HoriAdvance(face), face);
if (m_CharWidth[charcode] == 0xffff) {
m_CharWidth[charcode] = TT_Width;
} else if (TT_Width && !IsEmbedded()) {
m_CharBBox[charcode].right =
m_CharBBox[charcode].right * m_CharWidth[charcode] / TT_Width;
m_CharBBox[charcode].left =
m_CharBBox[charcode].left * m_CharWidth[charcode] / TT_Width;
}
}
}
void CPDF_SimpleFont::LoadCharWidths(const CPDF_Dictionary* font_desc) {
RetainPtr<const CPDF_Array> width_array = m_pFontDict->GetArrayFor("Widths");
m_bUseFontWidth = !width_array;
if (!width_array)
return;
if (font_desc && font_desc->KeyExist("MissingWidth")) {
int missing_width = font_desc->GetIntegerFor("MissingWidth");
std::fill(std::begin(m_CharWidth), std::end(m_CharWidth), missing_width);
}
size_t width_start = m_pFontDict->GetIntegerFor("FirstChar", 0);
size_t width_end = m_pFontDict->GetIntegerFor("LastChar", 0);
if (width_start > 255)
return;
if (width_end == 0 || width_end >= width_start + width_array->size())
width_end = width_start + width_array->size() - 1;
if (width_end > 255)
width_end = 255;
for (size_t i = width_start; i <= width_end; i++)
m_CharWidth[i] = width_array->GetIntegerAt(i - width_start);
}
void CPDF_SimpleFont::LoadDifferences(const CPDF_Dictionary* encoding) {
RetainPtr<const CPDF_Array> diffs = encoding->GetArrayFor("Differences");
if (!diffs)
return;
m_CharNames.resize(kInternalTableSize);
uint32_t cur_code = 0;
for (uint32_t i = 0; i < diffs->size(); i++) {
RetainPtr<const CPDF_Object> element = diffs->GetDirectObjectAt(i);
if (!element)
continue;
const CPDF_Name* name = element->AsName();
if (name) {
if (cur_code < m_CharNames.size())
m_CharNames[cur_code] = name->GetString();
cur_code++;
} else {
cur_code = element->GetInteger();
}
}
}
void CPDF_SimpleFont::LoadPDFEncoding(bool bEmbedded, bool bTrueType) {
RetainPtr<const CPDF_Object> pEncoding =
m_pFontDict->GetDirectObjectFor("Encoding");
if (!pEncoding) {
if (m_BaseFontName == "Symbol") {
m_BaseEncoding =
bTrueType ? FontEncoding::kMsSymbol : FontEncoding::kAdobeSymbol;
} else if (!bEmbedded && m_BaseEncoding == FontEncoding::kBuiltin) {
m_BaseEncoding = FontEncoding::kWinAnsi;
}
return;
}
if (pEncoding->IsName()) {
if (m_BaseEncoding == FontEncoding::kAdobeSymbol ||
m_BaseEncoding == FontEncoding::kZapfDingbats) {
return;
}
if (FontStyleIsSymbolic(m_Flags) && m_BaseFontName == "Symbol") {
if (!bTrueType)
m_BaseEncoding = FontEncoding::kAdobeSymbol;
return;
}
ByteString bsEncoding = pEncoding->GetString();
if (bsEncoding == pdfium::font_encodings::kMacExpertEncoding)
bsEncoding = pdfium::font_encodings::kWinAnsiEncoding;
GetPredefinedEncoding(bsEncoding, &m_BaseEncoding);
return;
}
const CPDF_Dictionary* pDict = pEncoding->AsDictionary();
if (!pDict)
return;
if (m_BaseEncoding != FontEncoding::kAdobeSymbol &&
m_BaseEncoding != FontEncoding::kZapfDingbats) {
ByteString bsEncoding = pDict->GetByteStringFor("BaseEncoding");
if (bTrueType && bsEncoding == pdfium::font_encodings::kMacExpertEncoding)
bsEncoding = pdfium::font_encodings::kWinAnsiEncoding;
GetPredefinedEncoding(bsEncoding, &m_BaseEncoding);
}
if ((!bEmbedded || bTrueType) && m_BaseEncoding == FontEncoding::kBuiltin)
m_BaseEncoding = FontEncoding::kStandard;
LoadDifferences(pDict);
}
int CPDF_SimpleFont::GetCharWidthF(uint32_t charcode) {
if (charcode > 0xff)
charcode = 0;
if (m_CharWidth[charcode] == 0xffff) {
LoadCharMetrics(charcode);
if (m_CharWidth[charcode] == 0xffff) {
m_CharWidth[charcode] = 0;
}
}
return m_CharWidth[charcode];
}
FX_RECT CPDF_SimpleFont::GetCharBBox(uint32_t charcode) {
if (charcode > 0xff)
charcode = 0;
if (m_CharBBox[charcode].left == -1)
LoadCharMetrics(charcode);
return m_CharBBox[charcode];
}
bool CPDF_SimpleFont::LoadCommon() {
RetainPtr<const CPDF_Dictionary> pFontDesc =
m_pFontDict->GetDictFor("FontDescriptor");
if (pFontDesc)
LoadFontDescriptor(pFontDesc.Get());
LoadCharWidths(pFontDesc.Get());
if (m_pFontFile) {
if (m_BaseFontName.GetLength() > 8 && m_BaseFontName[7] == '+')
m_BaseFontName = m_BaseFontName.Last(m_BaseFontName.GetLength() - 8);
} else {
LoadSubstFont();
}
if (!FontStyleIsSymbolic(m_Flags))
m_BaseEncoding = FontEncoding::kStandard;
LoadPDFEncoding(!!m_pFontFile, m_Font.IsTTFont());
LoadGlyphMap();
m_CharNames.clear();
if (!m_Font.GetFaceRec())
return true;
if (FontStyleIsAllCaps(m_Flags)) {
static const unsigned char kLowercases[][2] = {
{'a', 'z'}, {0xe0, 0xf6}, {0xf8, 0xfd}};
for (size_t range = 0; range < std::size(kLowercases); ++range) {
const auto& lower = kLowercases[range];
for (int i = lower[0]; i <= lower[1]; ++i) {
if (m_GlyphIndex[i] != 0xffff && m_pFontFile)
continue;
int j = i - 32;
m_GlyphIndex[i] = m_GlyphIndex[j];
if (m_CharWidth[j]) {
m_CharWidth[i] = m_CharWidth[j];
m_CharBBox[i] = m_CharBBox[j];
}
}
}
}
CheckFontMetrics();
return true;
}
void CPDF_SimpleFont::LoadSubstFont() {
if (!m_bUseFontWidth && !FontStyleIsFixedPitch(m_Flags)) {
int width = 0;
size_t i;
for (i = 0; i < kInternalTableSize; i++) {
if (m_CharWidth[i] == 0 || m_CharWidth[i] == 0xffff)
continue;
if (width == 0)
width = m_CharWidth[i];
else if (width != m_CharWidth[i])
break;
}
if (i == kInternalTableSize && width)
m_Flags |= FXFONT_FIXED_PITCH;
}
m_Font.LoadSubst(m_BaseFontName, IsTrueTypeFont(), m_Flags, GetFontWeight(),
m_ItalicAngle, FX_CodePage::kDefANSI, false);
}
bool CPDF_SimpleFont::IsUnicodeCompatible() const {
return m_BaseEncoding != FontEncoding::kBuiltin &&
m_BaseEncoding != FontEncoding::kAdobeSymbol &&
m_BaseEncoding != FontEncoding::kZapfDingbats;
}
WideString CPDF_SimpleFont::UnicodeFromCharCode(uint32_t charcode) const {
WideString unicode = CPDF_Font::UnicodeFromCharCode(charcode);
if (!unicode.IsEmpty())
return unicode;
wchar_t ret = m_Encoding.UnicodeFromCharCode((uint8_t)charcode);
if (ret == 0)
return WideString();
return WideString(ret);
}
uint32_t CPDF_SimpleFont::CharCodeFromUnicode(wchar_t unicode) const {
uint32_t ret = CPDF_Font::CharCodeFromUnicode(unicode);
if (ret)
return ret;
return m_Encoding.CharCodeFromUnicode(unicode);
}
bool CPDF_SimpleFont::HasFontWidths() const {
return !m_bUseFontWidth;
}