1 // Copyright (c) 2010 The Chromium 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 #include "pdf/pdfium/pdfium_page.h" 6 7 #include <math.h> 8 9 #include "base/logging.h" 10 #include "base/strings/string_number_conversions.h" 11 #include "base/strings/string_util.h" 12 #include "base/strings/utf_string_conversions.h" 13 #include "base/values.h" 14 #include "pdf/pdfium/pdfium_engine.h" 15 16 // Used when doing hit detection. 17 #define kTolerance 20.0 18 19 // Dictionary Value key names for returning the accessible page content as JSON. 20 const char kPageWidth[] = "width"; 21 const char kPageHeight[] = "height"; 22 const char kPageTextBox[] = "textBox"; 23 const char kTextBoxLeft[] = "left"; 24 const char kTextBoxTop[] = "top"; 25 const char kTextBoxWidth[] = "width"; 26 const char kTextBoxHeight[] = "height"; 27 const char kTextBoxFontSize[] = "fontSize"; 28 const char kTextBoxNodes[] = "textNodes"; 29 const char kTextNodeType[] = "type"; 30 const char kTextNodeText[] = "text"; 31 const char kTextNodeURL[] = "url"; 32 const char kTextNodeTypeText[] = "text"; 33 const char kTextNodeTypeURL[] = "url"; 34 const char kDocLinkURLPrefix[] = "#page"; 35 36 namespace chrome_pdf { 37 38 PDFiumPage::PDFiumPage(PDFiumEngine* engine, 39 int i, 40 const pp::Rect& r, 41 bool available) 42 : engine_(engine), 43 page_(NULL), 44 text_page_(NULL), 45 index_(i), 46 rect_(r), 47 calculated_links_(false), 48 available_(available) { 49 } 50 51 PDFiumPage::~PDFiumPage() { 52 } 53 54 void PDFiumPage::Unload() { 55 if (text_page_) { 56 FPDFText_ClosePage(text_page_); 57 text_page_ = NULL; 58 } 59 60 if (page_) { 61 if (engine_->form()) { 62 FORM_OnBeforeClosePage(page_, engine_->form()); 63 } 64 FPDF_ClosePage(page_); 65 page_ = NULL; 66 } 67 } 68 69 FPDF_PAGE PDFiumPage::GetPage() { 70 ScopedUnsupportedFeature scoped_unsupported_feature(engine_); 71 if (!available_) 72 return NULL; 73 if (!page_) { 74 page_ = FPDF_LoadPage(engine_->doc(), index_); 75 if (page_ && engine_->form()) { 76 FORM_OnAfterLoadPage(page_, engine_->form()); 77 } 78 } 79 return page_; 80 } 81 82 FPDF_PAGE PDFiumPage::GetPrintPage() { 83 ScopedUnsupportedFeature scoped_unsupported_feature(engine_); 84 if (!available_) 85 return NULL; 86 if (!page_) 87 page_ = FPDF_LoadPage(engine_->doc(), index_); 88 return page_; 89 } 90 91 void PDFiumPage::ClosePrintPage() { 92 if (page_) { 93 FPDF_ClosePage(page_); 94 page_ = NULL; 95 } 96 } 97 98 FPDF_TEXTPAGE PDFiumPage::GetTextPage() { 99 if (!available_) 100 return NULL; 101 if (!text_page_) 102 text_page_ = FPDFText_LoadPage(GetPage()); 103 return text_page_; 104 } 105 106 base::Value* PDFiumPage::GetAccessibleContentAsValue(int rotation) { 107 base::DictionaryValue* node = new base::DictionaryValue(); 108 109 if (!available_) 110 return node; 111 112 double width = FPDF_GetPageWidth(GetPage()); 113 double height = FPDF_GetPageHeight(GetPage()); 114 115 base::ListValue* text = new base::ListValue(); 116 int box_count = FPDFText_CountRects(GetTextPage(), 0, GetCharCount()); 117 for (int i = 0; i < box_count; i++) { 118 double left, top, right, bottom; 119 FPDFText_GetRect(GetTextPage(), i, &left, &top, &right, &bottom); 120 text->Append( 121 GetTextBoxAsValue(height, left, top, right, bottom, rotation)); 122 } 123 124 node->SetDouble(kPageWidth, width); 125 node->SetDouble(kPageHeight, height); 126 node->Set(kPageTextBox, text); // Takes ownership of |text| 127 128 return node; 129 } 130 131 base::Value* PDFiumPage::GetTextBoxAsValue(double page_height, 132 double left, double top, 133 double right, double bottom, 134 int rotation) { 135 base::string16 text_utf16; 136 int char_count = 137 FPDFText_GetBoundedText(GetTextPage(), left, top, right, bottom, NULL, 0); 138 if (char_count > 0) { 139 unsigned short* data = reinterpret_cast<unsigned short*>( 140 WriteInto(&text_utf16, char_count + 1)); 141 FPDFText_GetBoundedText(GetTextPage(), 142 left, top, right, bottom, 143 data, char_count); 144 } 145 std::string text_utf8 = base::UTF16ToUTF8(text_utf16); 146 147 FPDF_LINK link = FPDFLink_GetLinkAtPoint(GetPage(), left, top); 148 Area area; 149 std::vector<LinkTarget> targets; 150 if (link) { 151 targets.push_back(LinkTarget()); 152 area = GetLinkTarget(link, &targets[0]); 153 } else { 154 pp::Rect rect( 155 PageToScreen(pp::Point(), 1.0, left, top, right, bottom, rotation)); 156 GetLinks(rect, &targets); 157 area = targets.size() == 0 ? TEXT_AREA : WEBLINK_AREA; 158 } 159 160 int char_index = FPDFText_GetCharIndexAtPos(GetTextPage(), left, top, 161 kTolerance, kTolerance); 162 double font_size = FPDFText_GetFontSize(GetTextPage(), char_index); 163 164 base::DictionaryValue* node = new base::DictionaryValue(); 165 node->SetDouble(kTextBoxLeft, left); 166 node->SetDouble(kTextBoxTop, page_height - top); 167 node->SetDouble(kTextBoxWidth, right - left); 168 node->SetDouble(kTextBoxHeight, top - bottom); 169 node->SetDouble(kTextBoxFontSize, font_size); 170 171 base::ListValue* text_nodes = new base::ListValue(); 172 173 if (area == DOCLINK_AREA) { 174 std::string url = kDocLinkURLPrefix + base::IntToString(targets[0].page); 175 text_nodes->Append(CreateURLNode(text_utf8, url)); 176 } else if (area == WEBLINK_AREA && link) { 177 text_nodes->Append(CreateURLNode(text_utf8, targets[0].url)); 178 } else if (area == WEBLINK_AREA && !link) { 179 size_t start = 0; 180 for (size_t i = 0; i < targets.size(); ++i) { 181 // Remove the extra NULL character at end. 182 // Otherwise, find() will not return any matches. 183 if (targets[i].url.size() > 0 && 184 targets[i].url[targets[i].url.size() - 1] == '\0') { 185 targets[i].url.resize(targets[i].url.size() - 1); 186 } 187 // There should only ever be one NULL character 188 DCHECK(targets[i].url[targets[i].url.size() - 1] != '\0'); 189 190 // PDFium may change the case of generated links. 191 std::string lowerCaseURL = base::StringToLowerASCII(targets[i].url); 192 std::string lowerCaseText = base::StringToLowerASCII(text_utf8); 193 size_t pos = lowerCaseText.find(lowerCaseURL, start); 194 size_t length = targets[i].url.size(); 195 if (pos == std::string::npos) { 196 // Check if the link is a "mailto:" URL 197 if (lowerCaseURL.compare(0, 7, "mailto:") == 0) { 198 pos = lowerCaseText.find(lowerCaseURL.substr(7), start); 199 length -= 7; 200 } 201 202 if (pos == std::string::npos) { 203 // No match has been found. This should never happen. 204 continue; 205 } 206 } 207 208 std::string before_text = text_utf8.substr(start, pos - start); 209 if (before_text.size() > 0) 210 text_nodes->Append(CreateTextNode(before_text)); 211 std::string link_text = text_utf8.substr(pos, length); 212 text_nodes->Append(CreateURLNode(link_text, targets[i].url)); 213 214 start = pos + length; 215 } 216 std::string before_text = text_utf8.substr(start); 217 if (before_text.size() > 0) 218 text_nodes->Append(CreateTextNode(before_text)); 219 } else { 220 text_nodes->Append(CreateTextNode(text_utf8)); 221 } 222 223 node->Set(kTextBoxNodes, text_nodes); // Takes ownership of |text_nodes|. 224 return node; 225 } 226 227 base::Value* PDFiumPage::CreateTextNode(std::string text) { 228 base::DictionaryValue* node = new base::DictionaryValue(); 229 node->SetString(kTextNodeType, kTextNodeTypeText); 230 node->SetString(kTextNodeText, text); 231 return node; 232 } 233 234 base::Value* PDFiumPage::CreateURLNode(std::string text, std::string url) { 235 base::DictionaryValue* node = new base::DictionaryValue(); 236 node->SetString(kTextNodeType, kTextNodeTypeURL); 237 node->SetString(kTextNodeText, text); 238 node->SetString(kTextNodeURL, url); 239 return node; 240 } 241 242 PDFiumPage::Area PDFiumPage::GetCharIndex(const pp::Point& point, 243 int rotation, 244 int* char_index, 245 LinkTarget* target) { 246 if (!available_) 247 return NONSELECTABLE_AREA; 248 pp::Point point2 = point - rect_.point(); 249 double new_x, new_y; 250 FPDF_DeviceToPage(GetPage(), 0, 0, rect_.width(), rect_.height(), 251 rotation, point2.x(), point2.y(), &new_x, &new_y); 252 253 int rv = FPDFText_GetCharIndexAtPos( 254 GetTextPage(), new_x, new_y, kTolerance, kTolerance); 255 *char_index = rv; 256 257 FPDF_LINK link = FPDFLink_GetLinkAtPoint(GetPage(), new_x, new_y); 258 if (link) { 259 // We don't handle all possible link types of the PDF. For example, 260 // launch actions, cross-document links, etc. 261 // In that case, GetLinkTarget() will return NONSELECTABLE_AREA 262 // and we should proceed with area detection. 263 PDFiumPage::Area area = GetLinkTarget(link, target); 264 if (area != PDFiumPage::NONSELECTABLE_AREA) 265 return area; 266 } 267 268 if (rv < 0) 269 return NONSELECTABLE_AREA; 270 271 return GetLink(*char_index, target) != -1 ? WEBLINK_AREA : TEXT_AREA; 272 } 273 274 base::char16 PDFiumPage::GetCharAtIndex(int index) { 275 if (!available_) 276 return L'\0'; 277 return static_cast<base::char16>(FPDFText_GetUnicode(GetTextPage(), index)); 278 } 279 280 int PDFiumPage::GetCharCount() { 281 if (!available_) 282 return 0; 283 return FPDFText_CountChars(GetTextPage()); 284 } 285 286 PDFiumPage::Area PDFiumPage::GetLinkTarget( 287 FPDF_LINK link, PDFiumPage::LinkTarget* target) { 288 FPDF_DEST dest = FPDFLink_GetDest(engine_->doc(), link); 289 if (dest != NULL) 290 return GetDestinationTarget(dest, target); 291 292 FPDF_ACTION action = FPDFLink_GetAction(link); 293 if (action) { 294 switch (FPDFAction_GetType(action)) { 295 case PDFACTION_GOTO: { 296 FPDF_DEST dest = FPDFAction_GetDest(engine_->doc(), action); 297 if (dest) 298 return GetDestinationTarget(dest, target); 299 // TODO(gene): We don't fully support all types of the in-document 300 // links. Need to implement that. There is a bug to track that: 301 // http://code.google.com/p/chromium/issues/detail?id=55776 302 } break; 303 case PDFACTION_URI: { 304 if (target) { 305 size_t buffer_size = 306 FPDFAction_GetURIPath(engine_->doc(), action, NULL, 0); 307 if (buffer_size > 1) { 308 void* data = WriteInto(&target->url, buffer_size); 309 FPDFAction_GetURIPath(engine_->doc(), action, data, buffer_size); 310 } 311 } 312 return WEBLINK_AREA; 313 } break; 314 // TODO(gene): We don't support PDFACTION_REMOTEGOTO and PDFACTION_LAUNCH 315 // at the moment. 316 } 317 } 318 319 return NONSELECTABLE_AREA; 320 } 321 322 PDFiumPage::Area PDFiumPage::GetDestinationTarget( 323 FPDF_DEST destination, PDFiumPage::LinkTarget* target) { 324 int page_index = FPDFDest_GetPageIndex(engine_->doc(), destination); 325 if (target) { 326 target->page = page_index; 327 } 328 return DOCLINK_AREA; 329 } 330 331 int PDFiumPage::GetLink(int char_index, PDFiumPage::LinkTarget* target) { 332 if (!available_) 333 return -1; 334 335 CalculateLinks(); 336 337 // Get the bounding box of the rect again, since it might have moved because 338 // of the tolerance above. 339 double left, right, bottom, top; 340 FPDFText_GetCharBox(GetTextPage(), char_index, &left, &right, &bottom, &top); 341 342 pp::Point origin( 343 PageToScreen(pp::Point(), 1.0, left, top, right, bottom, 0).point()); 344 for (size_t i = 0; i < links_.size(); ++i) { 345 for (size_t j = 0; j < links_[i].rects.size(); ++j) { 346 if (links_[i].rects[j].Contains(origin)) { 347 if (target) 348 target->url = links_[i].url; 349 return i; 350 } 351 } 352 } 353 return -1; 354 } 355 356 std::vector<int> PDFiumPage::GetLinks(pp::Rect text_area, 357 std::vector<LinkTarget>* targets) { 358 if (!available_) 359 return std::vector<int>(); 360 361 CalculateLinks(); 362 363 std::vector<int> links; 364 365 for (size_t i = 0; i < links_.size(); ++i) { 366 for (size_t j = 0; j < links_[i].rects.size(); ++j) { 367 if (links_[i].rects[j].Intersects(text_area)) { 368 if (targets) { 369 LinkTarget target; 370 target.url = links_[i].url; 371 targets->push_back(target); 372 } 373 links.push_back(i); 374 } 375 } 376 } 377 return links; 378 } 379 380 void PDFiumPage::CalculateLinks() { 381 if (calculated_links_) 382 return; 383 384 calculated_links_ = true; 385 FPDF_PAGELINK links = FPDFLink_LoadWebLinks(GetTextPage()); 386 int count = FPDFLink_CountWebLinks(links); 387 for (int i = 0; i < count; ++i) { 388 base::string16 url; 389 int url_length = FPDFLink_GetURL(links, i, NULL, 0); 390 if (url_length > 1) { // WriteInto needs at least 2 characters. 391 unsigned short* data = 392 reinterpret_cast<unsigned short*>(WriteInto(&url, url_length)); 393 FPDFLink_GetURL(links, i, data, url_length); 394 } 395 Link link; 396 link.url = base::UTF16ToUTF8(url); 397 398 // If the link cannot be converted to a pp::Var, then it is not possible to 399 // pass it to JS. In this case, ignore the link like other PDF viewers. 400 // See http://crbug.com/312882 for an example. 401 pp::Var link_var(link.url); 402 if (!link_var.is_string()) 403 continue; 404 405 // Make sure all the characters in the URL are valid per RFC 1738. 406 // http://crbug.com/340326 has a sample bad PDF. 407 // GURL does not work correctly, e.g. it just strips \t \r \n. 408 bool is_invalid_url = false; 409 for (size_t j = 0; j < link.url.length(); ++j) { 410 // Control characters are not allowed. 411 // 0x7F is also a control character. 412 // 0x80 and above are not in US-ASCII. 413 if (link.url[j] < ' ' || link.url[j] >= '\x7F') { 414 is_invalid_url = true; 415 break; 416 } 417 } 418 if (is_invalid_url) 419 continue; 420 421 int rect_count = FPDFLink_CountRects(links, i); 422 for (int j = 0; j < rect_count; ++j) { 423 double left, top, right, bottom; 424 FPDFLink_GetRect(links, i, j, &left, &top, &right, &bottom); 425 link.rects.push_back( 426 PageToScreen(pp::Point(), 1.0, left, top, right, bottom, 0)); 427 } 428 links_.push_back(link); 429 } 430 FPDFLink_CloseWebLinks(links); 431 } 432 433 pp::Rect PDFiumPage::PageToScreen(const pp::Point& offset, 434 double zoom, 435 double left, 436 double top, 437 double right, 438 double bottom, 439 int rotation) { 440 if (!available_) 441 return pp::Rect(); 442 443 int new_left, new_top, new_right, new_bottom; 444 FPDF_PageToDevice( 445 page_, 446 static_cast<int>((rect_.x() - offset.x()) * zoom), 447 static_cast<int>((rect_.y() - offset.y()) * zoom), 448 static_cast<int>(ceil(rect_.width() * zoom)), 449 static_cast<int>(ceil(rect_.height() * zoom)), 450 rotation, left, top, &new_left, &new_top); 451 FPDF_PageToDevice( 452 page_, 453 static_cast<int>((rect_.x() - offset.x()) * zoom), 454 static_cast<int>((rect_.y() - offset.y()) * zoom), 455 static_cast<int>(ceil(rect_.width() * zoom)), 456 static_cast<int>(ceil(rect_.height() * zoom)), 457 rotation, right, bottom, &new_right, &new_bottom); 458 459 // If the PDF is rotated, the horizontal/vertical coordinates could be 460 // flipped. See 461 // http://www.netl.doe.gov/publications/proceedings/03/ubc/presentations/Goeckner-pres.pdf 462 if (new_right < new_left) 463 std::swap(new_right, new_left); 464 if (new_bottom < new_top) 465 std::swap(new_bottom, new_top); 466 467 return pp::Rect( 468 new_left, new_top, new_right - new_left + 1, new_bottom - new_top + 1); 469 } 470 471 PDFiumPage::Link::Link() { 472 } 473 474 PDFiumPage::Link::~Link() { 475 } 476 477 } // namespace chrome_pdf 478