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/parser/cpdf_array.h"
10 #include "core/fpdfapi/parser/cpdf_dictionary.h"
11 #include "core/fpdfapi/parser/cpdf_name.h"
12 #include "core/fxge/fx_font.h"
13 #include "core/fxge/fx_freetype.h"
14 #include "third_party/base/numerics/safe_math.h"
15
16 namespace {
17
GetPredefinedEncoding(const ByteString & value,int * basemap)18 void GetPredefinedEncoding(const ByteString& value, int* basemap) {
19 if (value == "WinAnsiEncoding")
20 *basemap = PDFFONT_ENCODING_WINANSI;
21 else if (value == "MacRomanEncoding")
22 *basemap = PDFFONT_ENCODING_MACROMAN;
23 else if (value == "MacExpertEncoding")
24 *basemap = PDFFONT_ENCODING_MACEXPERT;
25 else if (value == "PDFDocEncoding")
26 *basemap = PDFFONT_ENCODING_PDFDOC;
27 }
28
29 } // namespace
30
CPDF_SimpleFont(CPDF_Document * pDocument,CPDF_Dictionary * pFontDict)31 CPDF_SimpleFont::CPDF_SimpleFont(CPDF_Document* pDocument,
32 CPDF_Dictionary* pFontDict)
33 : CPDF_Font(pDocument, pFontDict) {
34 memset(m_CharWidth, 0xff, sizeof(m_CharWidth));
35 memset(m_GlyphIndex, 0xff, sizeof(m_GlyphIndex));
36 for (size_t i = 0; i < FX_ArraySize(m_CharBBox); ++i)
37 m_CharBBox[i] = FX_RECT(-1, -1, -1, -1);
38 }
39
40 CPDF_SimpleFont::~CPDF_SimpleFont() = default;
41
GlyphFromCharCode(uint32_t charcode,bool * pVertGlyph)42 int CPDF_SimpleFont::GlyphFromCharCode(uint32_t charcode, bool* pVertGlyph) {
43 if (pVertGlyph)
44 *pVertGlyph = false;
45
46 if (charcode > 0xff)
47 return -1;
48
49 int index = m_GlyphIndex[charcode];
50 if (index == 0xffff)
51 return -1;
52
53 return index;
54 }
55
LoadCharMetrics(int charcode)56 void CPDF_SimpleFont::LoadCharMetrics(int charcode) {
57 if (!m_Font.GetFaceRec())
58 return;
59
60 if (charcode < 0 || charcode > 0xff) {
61 return;
62 }
63 int glyph_index = m_GlyphIndex[charcode];
64 if (glyph_index == 0xffff) {
65 if (!m_pFontFile && charcode != 32) {
66 LoadCharMetrics(32);
67 m_CharBBox[charcode] = m_CharBBox[32];
68 if (m_bUseFontWidth) {
69 m_CharWidth[charcode] = m_CharWidth[32];
70 }
71 }
72 return;
73 }
74 FXFT_FaceRec* face = m_Font.GetFaceRec();
75 int err =
76 FT_Load_Glyph(face, glyph_index,
77 FT_LOAD_NO_SCALE | FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH);
78 if (err)
79 return;
80
81 int iHoriBearingX = FXFT_Get_Glyph_HoriBearingX(face);
82 int iHoriBearingY = FXFT_Get_Glyph_HoriBearingY(face);
83 m_CharBBox[charcode] =
84 FX_RECT(TT2PDF(iHoriBearingX, face), TT2PDF(iHoriBearingY, face),
85 TT2PDF(iHoriBearingX + FXFT_Get_Glyph_Width(face), face),
86 TT2PDF(iHoriBearingY - FXFT_Get_Glyph_Height(face), face));
87
88 if (m_bUseFontWidth) {
89 int TT_Width = TT2PDF(FXFT_Get_Glyph_HoriAdvance(face), face);
90 if (m_CharWidth[charcode] == 0xffff) {
91 m_CharWidth[charcode] = TT_Width;
92 } else if (TT_Width && !IsEmbedded()) {
93 m_CharBBox[charcode].right =
94 m_CharBBox[charcode].right * m_CharWidth[charcode] / TT_Width;
95 m_CharBBox[charcode].left =
96 m_CharBBox[charcode].left * m_CharWidth[charcode] / TT_Width;
97 }
98 }
99 }
100
LoadPDFEncoding(bool bEmbedded,bool bTrueType)101 void CPDF_SimpleFont::LoadPDFEncoding(bool bEmbedded, bool bTrueType) {
102 const CPDF_Object* pEncoding = m_pFontDict->GetDirectObjectFor("Encoding");
103 if (!pEncoding) {
104 if (m_BaseFontName == "Symbol") {
105 m_BaseEncoding = bTrueType ? PDFFONT_ENCODING_MS_SYMBOL
106 : PDFFONT_ENCODING_ADOBE_SYMBOL;
107 } else if (!bEmbedded && m_BaseEncoding == PDFFONT_ENCODING_BUILTIN) {
108 m_BaseEncoding = PDFFONT_ENCODING_WINANSI;
109 }
110 return;
111 }
112 if (pEncoding->IsName()) {
113 if (m_BaseEncoding == PDFFONT_ENCODING_ADOBE_SYMBOL ||
114 m_BaseEncoding == PDFFONT_ENCODING_ZAPFDINGBATS) {
115 return;
116 }
117 if (FontStyleIsSymbolic(m_Flags) && m_BaseFontName == "Symbol") {
118 if (!bTrueType)
119 m_BaseEncoding = PDFFONT_ENCODING_ADOBE_SYMBOL;
120 return;
121 }
122 ByteString bsEncoding = pEncoding->GetString();
123 if (bsEncoding.Compare("MacExpertEncoding") == 0) {
124 bsEncoding = "WinAnsiEncoding";
125 }
126 GetPredefinedEncoding(bsEncoding, &m_BaseEncoding);
127 return;
128 }
129
130 const CPDF_Dictionary* pDict = pEncoding->AsDictionary();
131 if (!pDict)
132 return;
133
134 if (m_BaseEncoding != PDFFONT_ENCODING_ADOBE_SYMBOL &&
135 m_BaseEncoding != PDFFONT_ENCODING_ZAPFDINGBATS) {
136 ByteString bsEncoding = pDict->GetStringFor("BaseEncoding");
137 if (bTrueType && bsEncoding.Compare("MacExpertEncoding") == 0)
138 bsEncoding = "WinAnsiEncoding";
139 GetPredefinedEncoding(bsEncoding, &m_BaseEncoding);
140 }
141 if ((!bEmbedded || bTrueType) && m_BaseEncoding == PDFFONT_ENCODING_BUILTIN)
142 m_BaseEncoding = PDFFONT_ENCODING_STANDARD;
143
144 const CPDF_Array* pDiffs = pDict->GetArrayFor("Differences");
145 if (!pDiffs)
146 return;
147
148 m_CharNames.resize(256);
149 uint32_t cur_code = 0;
150 for (uint32_t i = 0; i < pDiffs->size(); i++) {
151 const CPDF_Object* pElement = pDiffs->GetDirectObjectAt(i);
152 if (!pElement)
153 continue;
154
155 const CPDF_Name* pName = pElement->AsName();
156 if (pName) {
157 if (cur_code < 256)
158 m_CharNames[cur_code] = pName->GetString();
159 cur_code++;
160 } else {
161 cur_code = pElement->GetInteger();
162 }
163 }
164 }
165
GetCharWidthF(uint32_t charcode)166 uint32_t CPDF_SimpleFont::GetCharWidthF(uint32_t charcode) {
167 if (charcode > 0xff)
168 charcode = 0;
169
170 if (m_CharWidth[charcode] == 0xffff) {
171 LoadCharMetrics(charcode);
172 if (m_CharWidth[charcode] == 0xffff) {
173 m_CharWidth[charcode] = 0;
174 }
175 }
176 return m_CharWidth[charcode];
177 }
178
GetCharBBox(uint32_t charcode)179 FX_RECT CPDF_SimpleFont::GetCharBBox(uint32_t charcode) {
180 if (charcode > 0xff)
181 charcode = 0;
182
183 if (m_CharBBox[charcode].left == -1)
184 LoadCharMetrics(charcode);
185
186 return m_CharBBox[charcode];
187 }
188
LoadCommon()189 bool CPDF_SimpleFont::LoadCommon() {
190 const CPDF_Dictionary* pFontDesc = m_pFontDict->GetDictFor("FontDescriptor");
191 if (pFontDesc) {
192 LoadFontDescriptor(pFontDesc);
193 }
194 const CPDF_Array* pWidthArray = m_pFontDict->GetArrayFor("Widths");
195 m_bUseFontWidth = !pWidthArray;
196 if (pWidthArray) {
197 if (pFontDesc && pFontDesc->KeyExist("MissingWidth")) {
198 int MissingWidth = pFontDesc->GetIntegerFor("MissingWidth");
199 for (int i = 0; i < 256; i++) {
200 m_CharWidth[i] = MissingWidth;
201 }
202 }
203 size_t width_start = m_pFontDict->GetIntegerFor("FirstChar", 0);
204 size_t width_end = m_pFontDict->GetIntegerFor("LastChar", 0);
205 if (width_start <= 255) {
206 if (width_end == 0 || width_end >= width_start + pWidthArray->size())
207 width_end = width_start + pWidthArray->size() - 1;
208 if (width_end > 255)
209 width_end = 255;
210 for (size_t i = width_start; i <= width_end; i++)
211 m_CharWidth[i] = pWidthArray->GetIntegerAt(i - width_start);
212 }
213 }
214 if (m_pFontFile) {
215 if (m_BaseFontName.GetLength() > 8 && m_BaseFontName[7] == '+')
216 m_BaseFontName = m_BaseFontName.Last(m_BaseFontName.GetLength() - 8);
217 } else {
218 LoadSubstFont();
219 }
220 if (!FontStyleIsSymbolic(m_Flags))
221 m_BaseEncoding = PDFFONT_ENCODING_STANDARD;
222 LoadPDFEncoding(!!m_pFontFile, m_Font.IsTTFont());
223 LoadGlyphMap();
224 m_CharNames.clear();
225 if (!m_Font.GetFaceRec())
226 return true;
227
228 if (FontStyleIsAllCaps(m_Flags)) {
229 static const unsigned char kLowercases[][2] = {
230 {'a', 'z'}, {0xe0, 0xf6}, {0xf8, 0xfd}};
231 for (size_t range = 0; range < FX_ArraySize(kLowercases); ++range) {
232 const auto& lower = kLowercases[range];
233 for (int i = lower[0]; i <= lower[1]; ++i) {
234 if (m_GlyphIndex[i] != 0xffff && m_pFontFile)
235 continue;
236
237 int j = i - 32;
238 m_GlyphIndex[i] = m_GlyphIndex[j];
239 if (m_CharWidth[j]) {
240 m_CharWidth[i] = m_CharWidth[j];
241 m_CharBBox[i] = m_CharBBox[j];
242 }
243 }
244 }
245 }
246 CheckFontMetrics();
247 return true;
248 }
249
LoadSubstFont()250 void CPDF_SimpleFont::LoadSubstFont() {
251 if (!m_bUseFontWidth && !FontStyleIsFixedPitch(m_Flags)) {
252 int width = 0, i;
253 for (i = 0; i < 256; i++) {
254 if (m_CharWidth[i] == 0 || m_CharWidth[i] == 0xffff)
255 continue;
256
257 if (width == 0)
258 width = m_CharWidth[i];
259 else if (width != m_CharWidth[i])
260 break;
261 }
262 if (i == 256 && width)
263 m_Flags |= FXFONT_FIXED_PITCH;
264 }
265 m_Font.LoadSubst(m_BaseFontName, IsTrueTypeFont(), m_Flags, GetFontWeight(),
266 m_ItalicAngle, 0, false);
267 }
268
IsUnicodeCompatible() const269 bool CPDF_SimpleFont::IsUnicodeCompatible() const {
270 return m_BaseEncoding != PDFFONT_ENCODING_BUILTIN &&
271 m_BaseEncoding != PDFFONT_ENCODING_ADOBE_SYMBOL &&
272 m_BaseEncoding != PDFFONT_ENCODING_ZAPFDINGBATS;
273 }
274
UnicodeFromCharCode(uint32_t charcode) const275 WideString CPDF_SimpleFont::UnicodeFromCharCode(uint32_t charcode) const {
276 WideString unicode = CPDF_Font::UnicodeFromCharCode(charcode);
277 if (!unicode.IsEmpty())
278 return unicode;
279 wchar_t ret = m_Encoding.UnicodeFromCharCode((uint8_t)charcode);
280 if (ret == 0)
281 return WideString();
282 return ret;
283 }
284
CharCodeFromUnicode(wchar_t unicode) const285 uint32_t CPDF_SimpleFont::CharCodeFromUnicode(wchar_t unicode) const {
286 uint32_t ret = CPDF_Font::CharCodeFromUnicode(unicode);
287 if (ret)
288 return ret;
289 return m_Encoding.CharCodeFromUnicode(unicode);
290 }
291
HasFontWidths() const292 bool CPDF_SimpleFont::HasFontWidths() const {
293 return !m_bUseFontWidth;
294 }
295