1// Copyright 2016 PDFium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6
7#include "core/fpdfapi/font/cpdf_simplefont.h"
8
9#include "core/fpdfapi/font/font_int.h"
10#include "core/fpdfapi/parser/cpdf_array.h"
11#include "core/fpdfapi/parser/cpdf_dictionary.h"
12#include "core/fxge/fx_freetype.h"
13#include "third_party/base/numerics/safe_math.h"
14
15CPDF_SimpleFont::CPDF_SimpleFont() : m_BaseEncoding(PDFFONT_ENCODING_BUILTIN) {
16  FXSYS_memset(m_CharWidth, 0xff, sizeof(m_CharWidth));
17  FXSYS_memset(m_GlyphIndex, 0xff, sizeof(m_GlyphIndex));
18  FXSYS_memset(m_ExtGID, 0xff, sizeof(m_ExtGID));
19  for (size_t i = 0; i < FX_ArraySize(m_CharBBox); ++i)
20    m_CharBBox[i] = FX_RECT(-1, -1, -1, -1);
21}
22
23CPDF_SimpleFont::~CPDF_SimpleFont() {}
24
25int CPDF_SimpleFont::GlyphFromCharCode(uint32_t charcode, bool* pVertGlyph) {
26  if (pVertGlyph)
27    *pVertGlyph = false;
28
29  if (charcode > 0xff)
30    return -1;
31
32  int index = m_GlyphIndex[(uint8_t)charcode];
33  return index != 0xffff ? index : -1;
34}
35
36void CPDF_SimpleFont::LoadCharMetrics(int charcode) {
37  if (!m_Font.GetFace())
38    return;
39
40  if (charcode < 0 || charcode > 0xff) {
41    return;
42  }
43  int glyph_index = m_GlyphIndex[charcode];
44  if (glyph_index == 0xffff) {
45    if (!m_pFontFile && charcode != 32) {
46      LoadCharMetrics(32);
47      m_CharBBox[charcode] = m_CharBBox[32];
48      if (m_bUseFontWidth) {
49        m_CharWidth[charcode] = m_CharWidth[32];
50      }
51    }
52    return;
53  }
54  FXFT_Face face = m_Font.GetFace();
55  int err = FXFT_Load_Glyph(
56      face, glyph_index,
57      FXFT_LOAD_NO_SCALE | FXFT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH);
58  if (err)
59    return;
60
61  int iHoriBearingX = FXFT_Get_Glyph_HoriBearingX(face);
62  int iHoriBearingY = FXFT_Get_Glyph_HoriBearingY(face);
63  m_CharBBox[charcode] =
64      FX_RECT(TT2PDF(iHoriBearingX, face), TT2PDF(iHoriBearingY, face),
65              TT2PDF(iHoriBearingX + FXFT_Get_Glyph_Width(face), face),
66              TT2PDF(iHoriBearingY - FXFT_Get_Glyph_Height(face), face));
67
68  if (m_bUseFontWidth) {
69    int TT_Width = TT2PDF(FXFT_Get_Glyph_HoriAdvance(face), face);
70    if (m_CharWidth[charcode] == 0xffff) {
71      m_CharWidth[charcode] = TT_Width;
72    } else if (TT_Width && !IsEmbedded()) {
73      m_CharBBox[charcode].right =
74          m_CharBBox[charcode].right * m_CharWidth[charcode] / TT_Width;
75      m_CharBBox[charcode].left =
76          m_CharBBox[charcode].left * m_CharWidth[charcode] / TT_Width;
77    }
78  }
79}
80
81int CPDF_SimpleFont::GetCharWidthF(uint32_t charcode) {
82  if (charcode > 0xff)
83    charcode = 0;
84
85  if (m_CharWidth[charcode] == 0xffff) {
86    LoadCharMetrics(charcode);
87    if (m_CharWidth[charcode] == 0xffff) {
88      m_CharWidth[charcode] = 0;
89    }
90  }
91  return m_CharWidth[charcode];
92}
93
94FX_RECT CPDF_SimpleFont::GetCharBBox(uint32_t charcode) {
95  if (charcode > 0xff)
96    charcode = 0;
97
98  if (m_CharBBox[charcode].left == -1)
99    LoadCharMetrics(charcode);
100
101  return m_CharBBox[charcode];
102}
103
104bool CPDF_SimpleFont::LoadCommon() {
105  CPDF_Dictionary* pFontDesc = m_pFontDict->GetDictFor("FontDescriptor");
106  if (pFontDesc) {
107    LoadFontDescriptor(pFontDesc);
108  }
109  CPDF_Array* pWidthArray = m_pFontDict->GetArrayFor("Widths");
110  m_bUseFontWidth = !pWidthArray;
111  if (pWidthArray) {
112    if (pFontDesc && pFontDesc->KeyExist("MissingWidth")) {
113      int MissingWidth = pFontDesc->GetIntegerFor("MissingWidth");
114      for (int i = 0; i < 256; i++) {
115        m_CharWidth[i] = MissingWidth;
116      }
117    }
118    size_t width_start = m_pFontDict->GetIntegerFor("FirstChar", 0);
119    size_t width_end = m_pFontDict->GetIntegerFor("LastChar", 0);
120    if (width_start <= 255) {
121      if (width_end == 0 || width_end >= width_start + pWidthArray->GetCount())
122        width_end = width_start + pWidthArray->GetCount() - 1;
123      if (width_end > 255)
124        width_end = 255;
125      for (size_t i = width_start; i <= width_end; i++)
126        m_CharWidth[i] = pWidthArray->GetIntegerAt(i - width_start);
127    }
128  }
129  if (m_pFontFile) {
130    if (m_BaseFont.GetLength() > 8 && m_BaseFont[7] == '+')
131      m_BaseFont = m_BaseFont.Mid(8);
132  } else {
133    LoadSubstFont();
134  }
135  if (!(m_Flags & FXFONT_SYMBOLIC))
136    m_BaseEncoding = PDFFONT_ENCODING_STANDARD;
137  CPDF_Object* pEncoding = m_pFontDict->GetDirectObjectFor("Encoding");
138  LoadPDFEncoding(pEncoding, m_BaseEncoding, &m_CharNames, !!m_pFontFile,
139                  m_Font.IsTTFont());
140  LoadGlyphMap();
141  m_CharNames.clear();
142  if (!m_Font.GetFace())
143    return true;
144
145  if (m_Flags & FXFONT_ALLCAP) {
146    unsigned char kLowercases[][2] = {{'a', 'z'}, {0xe0, 0xf6}, {0xf8, 0xfd}};
147    for (size_t range = 0; range < FX_ArraySize(kLowercases); ++range) {
148      const auto& lower = kLowercases[range];
149      for (int i = lower[0]; i <= lower[1]; ++i) {
150        if (m_GlyphIndex[i] != 0xffff && m_pFontFile)
151          continue;
152
153        int j = i - 32;
154        m_GlyphIndex[i] = m_GlyphIndex[j];
155        if (m_CharWidth[j]) {
156          m_CharWidth[i] = m_CharWidth[j];
157          m_CharBBox[i] = m_CharBBox[j];
158        }
159      }
160    }
161  }
162  CheckFontMetrics();
163  return true;
164}
165
166void CPDF_SimpleFont::LoadSubstFont() {
167  if (!m_bUseFontWidth && !(m_Flags & FXFONT_FIXED_PITCH)) {
168    int width = 0, i;
169    for (i = 0; i < 256; i++) {
170      if (m_CharWidth[i] == 0 || m_CharWidth[i] == 0xffff)
171        continue;
172
173      if (width == 0)
174        width = m_CharWidth[i];
175      else if (width != m_CharWidth[i])
176        break;
177    }
178    if (i == 256 && width)
179      m_Flags |= FXFONT_FIXED_PITCH;
180  }
181  pdfium::base::CheckedNumeric<int> safeStemV(m_StemV);
182  if (m_StemV < 140)
183    safeStemV *= 5;
184  else
185    safeStemV = safeStemV * 4 + 140;
186  m_Font.LoadSubst(m_BaseFont, IsTrueTypeFont(), m_Flags,
187                   safeStemV.ValueOrDefault(FXFONT_FW_NORMAL), m_ItalicAngle, 0,
188                   false);
189}
190
191bool CPDF_SimpleFont::IsUnicodeCompatible() const {
192  return m_BaseEncoding != PDFFONT_ENCODING_BUILTIN &&
193         m_BaseEncoding != PDFFONT_ENCODING_ADOBE_SYMBOL &&
194         m_BaseEncoding != PDFFONT_ENCODING_ZAPFDINGBATS;
195}
196
197CFX_WideString CPDF_SimpleFont::UnicodeFromCharCode(uint32_t charcode) const {
198  CFX_WideString unicode = CPDF_Font::UnicodeFromCharCode(charcode);
199  if (!unicode.IsEmpty())
200    return unicode;
201  FX_WCHAR ret = m_Encoding.UnicodeFromCharCode((uint8_t)charcode);
202  if (ret == 0)
203    return CFX_WideString();
204  return ret;
205}
206
207uint32_t CPDF_SimpleFont::CharCodeFromUnicode(FX_WCHAR unicode) const {
208  uint32_t ret = CPDF_Font::CharCodeFromUnicode(unicode);
209  if (ret)
210    return ret;
211  return m_Encoding.CharCodeFromUnicode(unicode);
212}
213