OpenSystemsDevelopment / qpdf

Commit 989259892774095f387678ddcf7b5f540ef1f427

Authored by m-holger
1 parent 1a05b099

Refactor stream handling for clarity and efficiency 

Replaced shared_ptr with unique_ptr for pipeline management, reducing overhead and improving ownership semantics. Simplified conditional checks and modernized code to enhance readability by removing redundant variables and adjusting pointer usages. This refactor ensures better maintainability and minor performance gains in stream processing.
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Showing 1 changed file with 25 additions and 25 deletions
libqpdf/QPDF_Stream.cc
  View file @9892598
... ... @@ -447,18 +447,17 @@ Stream::pipeStreamData(
447 447 bool specialized_compression = false;
448 448 bool lossy_compression = false;
449 449 bool ignored;
450   - if (filterp == nullptr) {
  450 + if (!filterp) {
451 451 filterp = &ignored;
452 452 }
453 453 bool& filter = *filterp;
454   - filter = (!((encode_flags == 0) && (decode_level == qpdf_dl_none)));
455   - bool success = true;
  454 + filter = encode_flags || decode_level != qpdf_dl_none;
456 455 if (filter) {
457 456 filter = filterable(filters, specialized_compression, lossy_compression);
458 457 if ((decode_level < qpdf_dl_all) && lossy_compression) {
459 458 filter = false;
460 459 }
461   - if ((decode_level < qpdf_dl_specialized) && specialized_compression) {
  460 + if (decode_level < qpdf_dl_specialized && specialized_compression) {
462 461 filter = false;
463 462 }
464 463 QTC::TC(
... ... @@ -470,7 +469,7 @@ Stream::pipeStreamData(
470 469 : 3);
471 470 }
472 471  
473   - if (pipeline == nullptr) {
  472 + if (!pipeline) {
474 473 QTC::TC("qpdf", "QPDF_Stream pipeStreamData with null pipeline");
475 474 // Return value is whether we can filter in this case.
476 475 return filter;
... ... @@ -479,40 +478,37 @@ Stream::pipeStreamData(
479 478 // Construct the pipeline in reverse order. Force pipelines we create to be deleted when this
480 479 // function finishes. Pipelines created by QPDFStreamFilter objects will be deleted by those
481 480 // objects.
482   - std::vector<std::shared_ptr<Pipeline>> to_delete;
  481 + std::vector<std::unique_ptr<Pipeline>> to_delete;
483 482  
484   - std::shared_ptr<ContentNormalizer> normalizer;
485   - std::shared_ptr<Pipeline> new_pipeline;
  483 + ContentNormalizer normalizer;
486 484 if (filter) {
487 485 if (encode_flags & qpdf_ef_compress) {
488   - new_pipeline =
489   - std::make_shared<Pl_Flate>("compress stream", pipeline, Pl_Flate::a_deflate);
490   - to_delete.push_back(new_pipeline);
  486 + auto new_pipeline =
  487 + std::make_unique<Pl_Flate>("compress stream", pipeline, Pl_Flate::a_deflate);
491 488 pipeline = new_pipeline.get();
  489 + to_delete.push_back(std::move(new_pipeline));
492 490 }
493 491  
494 492 if (encode_flags & qpdf_ef_normalize) {
495   - normalizer = std::make_shared<ContentNormalizer>();
496   - new_pipeline =
497   - std::make_shared<Pl_QPDFTokenizer>("normalizer", normalizer.get(), pipeline);
498   - to_delete.push_back(new_pipeline);
  493 + auto new_pipeline =
  494 + std::make_unique<Pl_QPDFTokenizer>("normalizer", &normalizer, pipeline);
499 495 pipeline = new_pipeline.get();
  496 + to_delete.push_back(std::move(new_pipeline));
500 497 }
501 498  
502 499 for (auto iter = s->token_filters.rbegin(); iter != s->token_filters.rend(); ++iter) {
503   - new_pipeline =
504   - std::make_shared<Pl_QPDFTokenizer>("token filter", (*iter).get(), pipeline);
505   - to_delete.push_back(new_pipeline);
  500 + auto new_pipeline =
  501 + std::make_unique<Pl_QPDFTokenizer>("token filter", (*iter).get(), pipeline);
506 502 pipeline = new_pipeline.get();
  503 + to_delete.push_back(std::move(new_pipeline));
507 504 }
508 505  
509 506 for (auto f_iter = filters.rbegin(); f_iter != filters.rend(); ++f_iter) {
510   - auto decode_pipeline = (*f_iter)->getDecodePipeline(pipeline);
511   - if (decode_pipeline) {
  507 + if (auto decode_pipeline = (*f_iter)->getDecodePipeline(pipeline)) {
512 508 pipeline = decode_pipeline;
513 509 }
514 510 auto* flate = dynamic_cast<Pl_Flate*>(pipeline);
515   - if (flate != nullptr) {
  511 + if (flate) {
516 512 flate->setWarnCallback([this](char const* msg, int code) { warn(msg); });
517 513 }
518 514 }
... ... @@ -523,6 +519,7 @@ Stream::pipeStreamData(
523 519 pipeline->write(s->stream_data->getBuffer(), s->stream_data->getSize());
524 520 pipeline->finish();
525 521 } else if (s->stream_provider.get()) {
  522 + bool success = true;
526 523 Pl_Count count("stream provider count", pipeline);
527 524 if (s->stream_provider->supportsRetry()) {
528 525 if (!s->stream_provider->provideStreamData(
... ... @@ -552,6 +549,9 @@ Stream::pipeStreamData(
552 549 QTC::TC("qpdf", "QPDF_Stream provider length not provided");
553 550 s->stream_dict.replaceKey("/Length", QPDFObjectHandle::newInteger(actual_length));
554 551 }
  552 + if (!success) {
  553 + return false;
  554 + }
555 555 } else if (obj->getParsedOffset() == 0) {
556 556 QTC::TC("qpdf", "QPDF_Stream pipe no stream data");
557 557 throw std::logic_error("pipeStreamData called for stream with no data");
... ... @@ -568,13 +568,13 @@ Stream::pipeStreamData(
568 568 suppress_warnings,
569 569 will_retry)) {
570 570 filter = false;
571   - success = false;
  571 + return false;
572 572 }
573 573 }
574 574  
575   - if (filter && (!suppress_warnings) && normalizer.get() && normalizer->anyBadTokens()) {
  575 + if (filter && !suppress_warnings && normalizer.anyBadTokens()) {
576 576 warn("content normalization encountered bad tokens");
577   - if (normalizer->lastTokenWasBad()) {
  577 + if (normalizer.lastTokenWasBad()) {
578 578 QTC::TC("qpdf", "QPDF_Stream bad token at end during normalize");
579 579 warn(
580 580 "normalized content ended with a bad token; you may be able to resolve this by "
... ... @@ -587,7 +587,7 @@ Stream::pipeStreamData(
587 587 "in the manual.");
588 588 }
589 589  
590   - return success;
  590 + return true;
591 591 }
592 592  
593 593 void
... ...