Commit 727d14cb43106b252fae92c4c30e4b85a4f6d7d0
1 parent
7a23bfb6
Refactor `validatePDFVersion` and `findHeader`: simplify logic, improve readabil…
…ity, and replace deprecated API usage.
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26 additions
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27 deletions
libqpdf/QPDF.cc
| @@ -366,21 +366,20 @@ QPDF::numWarnings() const | @@ -366,21 +366,20 @@ QPDF::numWarnings() const | ||
| 366 | bool | 366 | bool |
| 367 | QPDF::validatePDFVersion(char const*& p, std::string& version) | 367 | QPDF::validatePDFVersion(char const*& p, std::string& version) |
| 368 | { | 368 | { |
| 369 | - bool valid = util::is_digit(*p); | ||
| 370 | - if (valid) { | ||
| 371 | - while (util::is_digit(*p)) { | ||
| 372 | - version.append(1, *p++); | ||
| 373 | - } | ||
| 374 | - if ((*p == '.') && util::is_digit(*(p + 1))) { | ||
| 375 | - version.append(1, *p++); | ||
| 376 | - while (util::is_digit(*p)) { | ||
| 377 | - version.append(1, *p++); | ||
| 378 | - } | ||
| 379 | - } else { | ||
| 380 | - valid = false; | ||
| 381 | - } | 369 | + if (!util::is_digit(*p)) { |
| 370 | + return false; | ||
| 371 | + } | ||
| 372 | + while (util::is_digit(*p)) { | ||
| 373 | + version.append(1, *p++); | ||
| 382 | } | 374 | } |
| 383 | - return valid; | 375 | + if (!(*p == '.' && util::is_digit(*(p + 1)))) { |
| 376 | + return false; | ||
| 377 | + } | ||
| 378 | + version.append(1, *p++); | ||
| 379 | + while (util::is_digit(*p)) { | ||
| 380 | + version.append(1, *p++); | ||
| 381 | + } | ||
| 382 | + return true; | ||
| 384 | } | 383 | } |
| 385 | 384 | ||
| 386 | bool | 385 | bool |
| @@ -388,26 +387,26 @@ QPDF::findHeader() | @@ -388,26 +387,26 @@ QPDF::findHeader() | ||
| 388 | { | 387 | { |
| 389 | qpdf_offset_t global_offset = m->file->tell(); | 388 | qpdf_offset_t global_offset = m->file->tell(); |
| 390 | std::string line = m->file->readLine(1024); | 389 | std::string line = m->file->readLine(1024); |
| 391 | - char const* p = line.c_str(); | 390 | + char const* p = line.data(); |
| 392 | if (strncmp(p, "%PDF-", 5) != 0) { | 391 | if (strncmp(p, "%PDF-", 5) != 0) { |
| 393 | throw std::logic_error("findHeader is not looking at %PDF-"); | 392 | throw std::logic_error("findHeader is not looking at %PDF-"); |
| 394 | } | 393 | } |
| 395 | p += 5; | 394 | p += 5; |
| 396 | std::string version; | 395 | std::string version; |
| 397 | - // Note: The string returned by line.c_str() is always null-terminated. The code below never | 396 | + // Note: The string returned by line.data() is always null-terminated. The code below never |
| 398 | // overruns the buffer because a null character always short-circuits further advancement. | 397 | // overruns the buffer because a null character always short-circuits further advancement. |
| 399 | - bool valid = validatePDFVersion(p, version); | ||
| 400 | - if (valid) { | ||
| 401 | - m->pdf_version = version; | ||
| 402 | - if (global_offset != 0) { | ||
| 403 | - // Empirical evidence strongly suggests that when there is leading material prior to the | ||
| 404 | - // PDF header, all explicit offsets in the file are such that 0 points to the beginning | ||
| 405 | - // of the header. | ||
| 406 | - QTC::TC("qpdf", "QPDF global offset"); | ||
| 407 | - m->file = std::shared_ptr<InputSource>(new OffsetInputSource(m->file, global_offset)); | ||
| 408 | - } | 398 | + if (!validatePDFVersion(p, version)) { |
| 399 | + return false; | ||
| 400 | + } | ||
| 401 | + m->pdf_version = version; | ||
| 402 | + if (global_offset != 0) { | ||
| 403 | + // Empirical evidence strongly suggests (codified in PDF 2.0 spec) that when there is | ||
| 404 | + // leading material prior to the PDF header, all explicit offsets in the file are such that | ||
| 405 | + // 0 points to the beginning of the header. | ||
| 406 | + QTC::TC("qpdf", "QPDF global offset"); | ||
| 407 | + m->file = std::make_shared<OffsetInputSource>(m->file, global_offset); | ||
| 409 | } | 408 | } |
| 410 | - return valid; | 409 | + return true; |
| 411 | } | 410 | } |
| 412 | 411 | ||
| 413 | void | 412 | void |