#include <qpdf/qpdf-config.h> // include first for large file support

#include <qpdf/QPDF_private.hh>

#include <array>

#include <atomic>

#include <cstring>

#include <limits>

#include <map>

#include <regex>

#include <sstream>

#include <vector>

#include <qpdf/FileInputSource.hh>

#include <qpdf/InputSource_private.hh>

#include <qpdf/OffsetInputSource.hh>

#include <qpdf/Pipeline.hh>

#include <qpdf/QPDFExc.hh>

#include <qpdf/QPDFLogger.hh>

#include <qpdf/QPDFObjectHandle_private.hh>

#include <qpdf/QPDFObject_private.hh>

#include <qpdf/QPDFParser.hh>

#include <qpdf/QTC.hh>

#include <qpdf/QUtil.hh>

#include <qpdf/Util.hh>

using namespace qpdf;

using namespace std::literals;

// This must be a fixed value. This API returns a const reference to it, and the C API relies on its

// being static as well.

std::string const QPDF::qpdf_version(QPDF_VERSION);

static char const* EMPTY_PDF = (

    // force line break

    "%PDF-1.3\n"

    "1 0 obj\n"

    "<< /Type /Catalog /Pages 2 0 R >>\n"

    "endobj\n"

    "2 0 obj\n"

    "<< /Type /Pages /Kids [] /Count 0 >>\n"

    "endobj\n"

    "xref\n"

    "0 3\n"

    "0000000000 65535 f \n"

    "0000000009 00000 n \n"

    "0000000058 00000 n \n"

    "trailer << /Size 3 /Root 1 0 R >>\n"

    "startxref\n"

    "110\n"

    "%%EOF\n");

namespace

{

    class InvalidInputSource: public InputSource

    {

      public:

        ~InvalidInputSource() override = default;

        qpdf_offset_t

        findAndSkipNextEOL() override

        {

            throwException();

            return 0;

        }

        std::string const&

        getName() const override

        {

            static std::string name("closed input source");

            return name;

        }

        qpdf_offset_t

        tell() override

        {

            throwException();

            return 0;

        }

        void

        seek(qpdf_offset_t offset, int whence) override

        {

            throwException();

        }

        void

        rewind() override

        {

            throwException();

        }

        size_t

        read(char* buffer, size_t length) override

        {

            throwException();

            return 0;

        }

        void

        unreadCh(char ch) override

        {

            throwException();

        }

      private:

        void

        throwException()

        {

            throw std::logic_error(

                "QPDF operation attempted on a QPDF object with no input "

                "source. QPDF operations are invalid before processFile (or "

                "another process method) or after closeInputSource");

        }

    };

} // namespace

QPDF::ForeignStreamData::ForeignStreamData(

    std::shared_ptr<EncryptionParameters> encp,

    std::shared_ptr<InputSource> file,

    QPDFObjGen foreign_og,

    qpdf_offset_t offset,

    size_t length,

    QPDFObjectHandle local_dict,

    bool is_root_metadata) :

    encp(encp),

    file(file),

    foreign_og(foreign_og),

    offset(offset),

    length(length),

    local_dict(local_dict),

    is_root_metadata(is_root_metadata)

{

}

QPDF::CopiedStreamDataProvider::CopiedStreamDataProvider(QPDF& destination_qpdf) :

    QPDFObjectHandle::StreamDataProvider(true),

    destination_qpdf(destination_qpdf)

{

}

bool

QPDF::CopiedStreamDataProvider::provideStreamData(

    QPDFObjGen const& og, Pipeline* pipeline, bool suppress_warnings, bool will_retry)

{

    std::shared_ptr<ForeignStreamData> foreign_data = foreign_stream_data[og];

    bool result = false;

    if (foreign_data.get()) {

        result = destination_qpdf.pipeForeignStreamData(

            foreign_data, pipeline, suppress_warnings, will_retry);

        QTC::TC("qpdf", "QPDF copy foreign with data", result ? 0 : 1);

    } else {

        auto foreign_stream = foreign_streams[og];

        result = foreign_stream.pipeStreamData(

            pipeline, nullptr, 0, qpdf_dl_none, suppress_warnings, will_retry);

        QTC::TC("qpdf", "QPDF copy foreign with foreign_stream", result ? 0 : 1);

    }

    return result;

}

void

QPDF::CopiedStreamDataProvider::registerForeignStream(

    QPDFObjGen const& local_og, QPDFObjectHandle foreign_stream)

{

    this->foreign_streams[local_og] = foreign_stream;

}

void

QPDF::CopiedStreamDataProvider::registerForeignStream(

    QPDFObjGen const& local_og, std::shared_ptr<ForeignStreamData> foreign_stream)

{

    this->foreign_stream_data[local_og] = foreign_stream;

}

QPDF::StringDecrypter::StringDecrypter(QPDF* qpdf, QPDFObjGen og) :

    qpdf(qpdf),

    og(og)

{

}

std::string const&

QPDF::QPDFVersion()

{

    // The C API relies on this being a static value.

    return QPDF::qpdf_version;

}

QPDF::Members::Members() :

    log(QPDFLogger::defaultLogger()),

    file(new InvalidInputSource()),

    encp(new EncryptionParameters)

{

}

QPDF::QPDF() :

    m(std::make_unique<Members>())

{

    m->tokenizer.allowEOF();

    // Generate a unique ID. It just has to be unique among all QPDF objects allocated throughout

    // the lifetime of this running application.

    static std::atomic<unsigned long long> unique_id{0};

    m->unique_id = unique_id.fetch_add(1ULL);

}

// Provide access to disconnect(). Disconnect will in due course be merged into the current ObjCache

// (future Objects::Entry) to centralize all QPDF access to QPDFObject.

class Disconnect: BaseHandle

{

  public:

    Disconnect(std::shared_ptr<QPDFObject> const& obj) :

        BaseHandle(obj)

    {

    }

    void

    disconnect()

    {

        BaseHandle::disconnect(false);

        if (raw_type_code() != ::ot_null) {

            obj->value = QPDF_Destroyed();

        }

    }

};

QPDF::~QPDF()

{

    // If two objects are mutually referential (through each object having an array or dictionary

    // that contains an indirect reference to the other), the circular references in the

    // std::shared_ptr objects will prevent the objects from being deleted. Walk through all objects

    // in the object cache, which is those objects that we read from the file, and break all

    // resolved indirect references by replacing them with an internal object type representing that

    // they have been destroyed. Note that we can't break references like this at any time when the

    // QPDF object is active. The call to reset also causes all direct QPDFObjectHandle objects that

    // are reachable from this object to release their association with this QPDF. Direct objects

    // are not destroyed since they can be moved to other QPDF objects safely.

    // At this point, obviously no one is still using the QPDF object, but we'll explicitly clear

    // the xref table anyway just to prevent any possibility of resolve() succeeding.

    m->xref_table.clear();

    for (auto const& iter: m->obj_cache) {

        Disconnect(iter.second.object).disconnect();

    }

}

std::shared_ptr<QPDF>

QPDF::create()

{

    return std::make_shared<QPDF>();

}

void

QPDF::processFile(char const* filename, char const* password)

{

    auto* fi = new FileInputSource(filename);

    processInputSource(std::shared_ptr<InputSource>(fi), password);

}

void

QPDF::processFile(char const* description, FILE* filep, bool close_file, char const* password)

{

    auto* fi = new FileInputSource(description, filep, close_file);

    processInputSource(std::shared_ptr<InputSource>(fi), password);

}

void

QPDF::processMemoryFile(

    char const* description, char const* buf, size_t length, char const* password)

{

    auto is = std::make_shared<is::OffsetBuffer>(description, std::string_view{buf, length});

    processInputSource(is, password);

}

void

QPDF::processInputSource(std::shared_ptr<InputSource> source, char const* password)

{

    m->file = source;

    parse(password);

}

void

QPDF::closeInputSource()

{

    m->file = std::shared_ptr<InputSource>(new InvalidInputSource());

}

void

QPDF::setPasswordIsHexKey(bool val)

{

    m->provided_password_is_hex_key = val;

}

void

QPDF::emptyPDF()

{

    processMemoryFile("empty PDF", EMPTY_PDF, strlen(EMPTY_PDF));

}

void

QPDF::registerStreamFilter(

    std::string const& filter_name, std::function<std::shared_ptr<QPDFStreamFilter>()> factory)

{

    qpdf::Stream::registerStreamFilter(filter_name, factory);

}

void

QPDF::setIgnoreXRefStreams(bool val)

{

    m->ignore_xref_streams = val;

}

std::shared_ptr<QPDFLogger>

QPDF::getLogger()

{

    return m->log;

}

void

QPDF::setLogger(std::shared_ptr<QPDFLogger> l)

{

    m->log = l;

}

void

QPDF::setOutputStreams(std::ostream* out, std::ostream* err)

{

    setLogger(QPDFLogger::create());

    m->log->setOutputStreams(out, err);

}

void

QPDF::setSuppressWarnings(bool val)

{

    m->suppress_warnings = val;

}

void

QPDF::setMaxWarnings(size_t val)

{

    m->max_warnings = val;

}

void

QPDF::setAttemptRecovery(bool val)

{

    m->attempt_recovery = val;

}

void

QPDF::setImmediateCopyFrom(bool val)

{

    m->immediate_copy_from = val;

}

std::vector<QPDFExc>

QPDF::getWarnings()

{

    std::vector<QPDFExc> result = m->warnings;

    m->warnings.clear();

    return result;

}

bool

QPDF::anyWarnings() const

{

    return !m->warnings.empty();

}

size_t

QPDF::numWarnings() const

{

    return m->warnings.size();

}

bool

QPDF::validatePDFVersion(char const*& p, std::string& version)

{

    if (!util::is_digit(*p)) {

        return false;

    }

    while (util::is_digit(*p)) {

        version.append(1, *p++);

    }

    if (!(*p == '.' && util::is_digit(*(p + 1)))) {

        return false;

    }

    version.append(1, *p++);

    while (util::is_digit(*p)) {

        version.append(1, *p++);

    }

    return true;

}

bool

QPDF::findHeader()

{

    qpdf_offset_t global_offset = m->file->tell();

    std::string line = m->file->readLine(1024);

    char const* p = line.data();

    if (strncmp(p, "%PDF-", 5) != 0) {

        throw std::logic_error("findHeader is not looking at %PDF-");

    }

    p += 5;

    std::string version;

    // Note: The string returned by line.data() is always null-terminated. The code below never

    // overruns the buffer because a null character always short-circuits further advancement.

    if (!validatePDFVersion(p, version)) {

        return false;

    }

    m->pdf_version = version;

    if (global_offset != 0) {

        // Empirical evidence strongly suggests (codified in PDF 2.0 spec) that when there is

        // leading material prior to the PDF header, all explicit offsets in the file are such that

        // 0 points to the beginning of the header.

        QTC::TC("qpdf", "QPDF global offset");

        m->file = std::make_shared<OffsetInputSource>(m->file, global_offset);

    }

    return true;

}

void

QPDF::warn(QPDFExc const& e)

{

    if (m->max_warnings > 0 && m->warnings.size() >= m->max_warnings) {

        stopOnError("Too many warnings - file is too badly damaged");

    }

    m->warnings.push_back(e);

    if (!m->suppress_warnings) {

        *m->log->getWarn() << "WARNING: " << m->warnings.back().what() << "\n";

    }

}

void

QPDF::warn(

    qpdf_error_code_e error_code,

    std::string const& object,

    qpdf_offset_t offset,

    std::string const& message)

{

    warn(QPDFExc(error_code, getFilename(), object, offset, message));

}

QPDFObjectHandle

QPDF::newReserved()

{

    return makeIndirectFromQPDFObject(QPDFObject::create<QPDF_Reserved>());

}

QPDFObjectHandle

QPDF::newIndirectNull()

{

    return makeIndirectFromQPDFObject(QPDFObject::create<QPDF_Null>());

}

QPDFObjectHandle

QPDF::newStream()

{

    return makeIndirectObject(

        qpdf::Stream(*this, nextObjGen(), QPDFObjectHandle::newDictionary(), 0, 0));

}

QPDFObjectHandle

QPDF::newStream(std::shared_ptr<Buffer> data)

{

    auto result = newStream();

    result.replaceStreamData(data, QPDFObjectHandle::newNull(), QPDFObjectHandle::newNull());

    return result;

}

QPDFObjectHandle

QPDF::newStream(std::string const& data)

{

    auto result = newStream();

    result.replaceStreamData(data, QPDFObjectHandle::newNull(), QPDFObjectHandle::newNull());

    return result;

}

QPDFObjectHandle

QPDF::getObject(int objid, int generation)

{

    return getObject(QPDFObjGen(objid, generation));

}

QPDFObjectHandle

QPDF::getObjectByObjGen(QPDFObjGen og)

{

    return getObject(og);

}

QPDFObjectHandle

QPDF::getObjectByID(int objid, int generation)

{

    return getObject(QPDFObjGen(objid, generation));

}

QPDFObjectHandle

QPDF::copyForeignObject(QPDFObjectHandle foreign)

{

    // Here's an explanation of what's going on here.

    //

    // A QPDFObjectHandle that is an indirect object has an owning QPDF. The object ID and

    // generation refers to an object in the owning QPDF. When we copy the QPDFObjectHandle from a

    // foreign QPDF into the local QPDF, we have to replace all indirect object references with

    // references to the corresponding object in the local file.

    //

    // To do this, we maintain mappings from foreign object IDs to local object IDs for each foreign

    // QPDF that we are copying from. The mapping is stored in an ObjCopier, which contains a

    // mapping from the foreign ObjGen to the local QPDFObjectHandle.

    //

    // To copy, we do a deep traversal of the foreign object with loop detection to discover all

    // indirect objects that are encountered, stopping at page boundaries. Whenever we encounter an

    // indirect object, we check to see if we have already created a local copy of it. If not, we

    // allocate a "reserved" object (or, for a stream, just a new stream) and store in the map the

    // mapping from the foreign object ID to the new object. While we

    // do this, we keep a list of objects to copy.

    //

    // Once we are done with the traversal, we copy all the objects that we need to copy. However,

    // the copies will contain indirect object IDs that refer to objects in the foreign file. We

    // need to replace them with references to objects in the local file. This is what

    // replaceForeignIndirectObjects does. Once we have created a copy of the foreign object with

    // all the indirect references replaced with new ones in the local context, we can replace the

    // local reserved object with the copy. This mechanism allows us to copy objects with circular

    // references in any order.

    // For streams, rather than copying the objects, we set up the stream data to pull from the

    // original stream by using a stream data provider. This is done in a manner that doesn't

    // require the original QPDF object but may require the original source of the stream data with

    // special handling for immediate_copy_from. This logic is also in

    // replaceForeignIndirectObjects.

    // Note that we explicitly allow use of copyForeignObject on page objects. It is a documented

    // use case to copy pages this way if the intention is to not update the pages tree.

    if (!foreign.isIndirect()) {

        QTC::TC("qpdf", "QPDF copyForeign direct");

        throw std::logic_error("QPDF::copyForeign called with direct object handle");

    }

    QPDF& other = foreign.getQPDF();

    if (&other == this) {

        QTC::TC("qpdf", "QPDF copyForeign not foreign");

        throw std::logic_error("QPDF::copyForeign called with object from this QPDF");

    }

    ObjCopier& obj_copier = m->object_copiers[other.m->unique_id];

    if (!obj_copier.visiting.empty()) {

        throw std::logic_error(

            "obj_copier.visiting is not empty at the beginning of copyForeignObject");

    }

    // Make sure we have an object in this file for every referenced object in the old file.

    // obj_copier.object_map maps foreign QPDFObjGen to local objects.  For everything new that we

    // have to copy, the local object will be a reservation, unless it is a stream, in which case

    // the local object will already be a stream.

    reserveObjects(foreign, obj_copier, true);

    if (!obj_copier.visiting.empty()) {

        throw std::logic_error("obj_copier.visiting is not empty after reserving objects");

    }

    // Copy any new objects and replace the reservations.

    for (auto& to_copy: obj_copier.to_copy) {

        QPDFObjectHandle copy = replaceForeignIndirectObjects(to_copy, obj_copier, true);

        if (!to_copy.isStream()) {

            QPDFObjGen og(to_copy.getObjGen());

            replaceReserved(obj_copier.object_map[og], copy);

        }

    }

    obj_copier.to_copy.clear();

    auto og = foreign.getObjGen();

    if (!obj_copier.object_map.contains(og)) {

        warn(damagedPDF(

            other.getFilename() + " object " + og.unparse(' '),

            foreign.getParsedOffset(),

            "unexpected reference to /Pages object while copying foreign object; replacing with "

            "null"));

        return QPDFObjectHandle::newNull();

    }

    return obj_copier.object_map[foreign.getObjGen()];

}

void

QPDF::reserveObjects(QPDFObjectHandle foreign, ObjCopier& obj_copier, bool top)

{

    auto foreign_tc = foreign.getTypeCode();

    if (foreign_tc == ::ot_reserved) {

        throw std::logic_error("QPDF: attempting to copy a foreign reserved object");

    }

    if (foreign.isPagesObject()) {

        QTC::TC("qpdf", "QPDF not copying pages object");

        return;

    }

    if (foreign.isIndirect()) {

        QPDFObjGen foreign_og(foreign.getObjGen());

        if (!obj_copier.visiting.add(foreign_og)) {

            QTC::TC("qpdf", "QPDF loop reserving objects");

            return;

        }

        if (obj_copier.object_map.contains(foreign_og)) {

            QTC::TC("qpdf", "QPDF already reserved object");

            if (!(top && foreign.isPageObject() && obj_copier.object_map[foreign_og].isNull())) {

                obj_copier.visiting.erase(foreign);

                return;

            }

        } else {

            QTC::TC("qpdf", "QPDF copy indirect");

            obj_copier.object_map[foreign_og] =

                foreign.isStream() ? newStream() : newIndirectNull();

            if ((!top) && foreign.isPageObject()) {

                QTC::TC("qpdf", "QPDF not crossing page boundary");

                obj_copier.visiting.erase(foreign_og);

                return;

            }

        }

        obj_copier.to_copy.push_back(foreign);

    }

    if (foreign_tc == ::ot_array) {

        QTC::TC("qpdf", "QPDF reserve array");

        for (auto const& item: foreign.as_array()) {

            reserveObjects(item, obj_copier, false);

        }

    } else if (foreign_tc == ::ot_dictionary) {

        QTC::TC("qpdf", "QPDF reserve dictionary");

        for (auto const& item: foreign.as_dictionary()) {

            if (!item.second.null()) {

                reserveObjects(item.second, obj_copier, false);

            }

        }

    } else if (foreign_tc == ::ot_stream) {

        QTC::TC("qpdf", "QPDF reserve stream");

        reserveObjects(foreign.getDict(), obj_copier, false);

    }

    obj_copier.visiting.erase(foreign);

}

QPDFObjectHandle

QPDF::replaceForeignIndirectObjects(QPDFObjectHandle foreign, ObjCopier& obj_copier, bool top)

{

    auto foreign_tc = foreign.getTypeCode();

    QPDFObjectHandle result;

    if ((!top) && foreign.isIndirect()) {

        QTC::TC("qpdf", "QPDF replace indirect");

        auto mapping = obj_copier.object_map.find(foreign.getObjGen());

        if (mapping == obj_copier.object_map.end()) {

            // This case would occur if this is a reference to a Pages object that we didn't

            // traverse into.

            QTC::TC("qpdf", "QPDF replace foreign indirect with null");

            result = QPDFObjectHandle::newNull();

        } else {

            result = mapping->second;

        }

    } else if (foreign_tc == ::ot_array) {

        QTC::TC("qpdf", "QPDF replace array");

        result = QPDFObjectHandle::newArray();

        for (auto const& item: foreign.as_array()) {

            result.appendItem(replaceForeignIndirectObjects(item, obj_copier, false));

        }

    } else if (foreign_tc == ::ot_dictionary) {

        QTC::TC("qpdf", "QPDF replace dictionary");

        result = QPDFObjectHandle::newDictionary();

        for (auto const& [key, value]: foreign.as_dictionary()) {

            if (!value.null()) {

                result.replaceKey(key, replaceForeignIndirectObjects(value, obj_copier, false));

            }

        }

    } else if (foreign_tc == ::ot_stream) {

        QTC::TC("qpdf", "QPDF replace stream");

        result = obj_copier.object_map[foreign.getObjGen()];

        QPDFObjectHandle dict = result.getDict();

        QPDFObjectHandle old_dict = foreign.getDict();

        for (auto const& [key, value]: old_dict.as_dictionary()) {

            if (!value.null()) {

                dict.replaceKey(key, replaceForeignIndirectObjects(value, obj_copier, false));

            }

        }

        copyStreamData(result, foreign);

    } else {

        foreign.assertScalar();

        result = foreign;

        result.makeDirect();

    }

    if (top && (!result.isStream()) && result.isIndirect()) {

        throw std::logic_error("replacement for foreign object is indirect");

    }

    return result;

}

void

QPDF::copyStreamData(QPDFObjectHandle result, QPDFObjectHandle foreign)

{

    // This method was originally written for copying foreign streams, but it is used by

    // QPDFObjectHandle to copy streams from the same QPDF object as well.

    QPDFObjectHandle dict = result.getDict();

    QPDFObjectHandle old_dict = foreign.getDict();

    if (m->copied_stream_data_provider == nullptr) {

        m->copied_stream_data_provider = new CopiedStreamDataProvider(*this);

        m->copied_streams =

            std::shared_ptr<QPDFObjectHandle::StreamDataProvider>(m->copied_stream_data_provider);

    }

    QPDFObjGen local_og(result.getObjGen());

    // Copy information from the foreign stream so we can pipe its data later without keeping the

    // original QPDF object around.

    QPDF& foreign_stream_qpdf =

        foreign.getQPDF("unable to retrieve owning qpdf from foreign stream");

    auto stream = foreign.as_stream();

    if (!stream) {

        throw std::logic_error("unable to retrieve underlying stream object from foreign stream");

    }

    std::shared_ptr<Buffer> stream_buffer = stream.getStreamDataBuffer();

    if ((foreign_stream_qpdf.m->immediate_copy_from) && (stream_buffer == nullptr)) {

        // Pull the stream data into a buffer before attempting the copy operation. Do it on the

        // source stream so that if the source stream is copied multiple times, we don't have to

        // keep duplicating the memory.

        QTC::TC("qpdf", "QPDF immediate copy stream data");

        foreign.replaceStreamData(

            foreign.getRawStreamData(),

            old_dict.getKey("/Filter"),

            old_dict.getKey("/DecodeParms"));

        stream_buffer = stream.getStreamDataBuffer();

    }

    std::shared_ptr<QPDFObjectHandle::StreamDataProvider> stream_provider =

        stream.getStreamDataProvider();

    if (stream_buffer.get()) {

        QTC::TC("qpdf", "QPDF copy foreign stream with buffer");

        result.replaceStreamData(

            stream_buffer, dict.getKey("/Filter"), dict.getKey("/DecodeParms"));

    } else if (stream_provider.get()) {

        // In this case, the remote stream's QPDF must stay in scope.

        QTC::TC("qpdf", "QPDF copy foreign stream with provider");

        m->copied_stream_data_provider->registerForeignStream(local_og, foreign);

        result.replaceStreamData(

            m->copied_streams, dict.getKey("/Filter"), dict.getKey("/DecodeParms"));

    } else {

        auto foreign_stream_data = std::make_shared<ForeignStreamData>(

            foreign_stream_qpdf.m->encp,

            foreign_stream_qpdf.m->file,

            foreign,

            foreign.getParsedOffset(),

            stream.getLength(),

            dict,

            stream.isRootMetadata());

        m->copied_stream_data_provider->registerForeignStream(local_og, foreign_stream_data);

        result.replaceStreamData(

            m->copied_streams, dict.getKey("/Filter"), dict.getKey("/DecodeParms"));

    }

}

unsigned long long

QPDF::getUniqueId() const

{

    return m->unique_id;

}

std::string

QPDF::getFilename() const

{

    return m->file->getName();

}

PDFVersion

QPDF::getVersionAsPDFVersion()

{

    int major = 1;

    int minor = 3;

    int extension_level = getExtensionLevel();

    std::regex v("^[[:space:]]*([0-9]+)\\.([0-9]+)");

    std::smatch match;

    if (std::regex_search(m->pdf_version, match, v)) {

        major = QUtil::string_to_int(match[1].str().c_str());

        minor = QUtil::string_to_int(match[2].str().c_str());

    }

    return {major, minor, extension_level};

}

std::string

QPDF::getPDFVersion() const

{

    return m->pdf_version;

}

int

QPDF::getExtensionLevel()

{

    int result = 0;

    QPDFObjectHandle obj = getRoot();

    if (obj.hasKey("/Extensions")) {

        obj = obj.getKey("/Extensions");

        if (obj.isDictionary() && obj.hasKey("/ADBE")) {

            obj = obj.getKey("/ADBE");

            if (obj.isDictionary() && obj.hasKey("/ExtensionLevel")) {

                obj = obj.getKey("/ExtensionLevel");

                if (obj.isInteger()) {

                    result = obj.getIntValueAsInt();

                }

            }

        }

    }

    return result;

}

QPDFObjectHandle

QPDF::getTrailer()

{

    return m->trailer;

}

QPDFObjectHandle

QPDF::getRoot()

{

    QPDFObjectHandle root = m->trailer.getKey("/Root");

    if (!root.isDictionary()) {

        throw damagedPDF("", -1, "unable to find /Root dictionary");

    } else if (

        // Check_mode is an interim solution to request #810 pending a more comprehensive review of

        // the approach to more extensive checks and warning levels.

        m->check_mode && !root.getKey("/Type").isNameAndEquals("/Catalog")) {

        warn(damagedPDF("", -1, "catalog /Type entry missing or invalid"));

        root.replaceKey("/Type", "/Catalog"_qpdf);

    }

    return root;

}

std::map<QPDFObjGen, QPDFXRefEntry>

QPDF::getXRefTable()

{

    return getXRefTableInternal();

}

std::map<QPDFObjGen, QPDFXRefEntry> const&

QPDF::getXRefTableInternal()

{

    if (!m->parsed) {

        throw std::logic_error("QPDF::getXRefTable called before parsing.");

    }

    return m->xref_table;

}

bool

QPDF::pipeStreamData(

    std::shared_ptr<EncryptionParameters> encp,

    std::shared_ptr<InputSource> file,

    QPDF& qpdf_for_warning,

    QPDFObjGen og,

    qpdf_offset_t offset,

    size_t length,

    QPDFObjectHandle stream_dict,

    bool is_root_metadata,

    Pipeline* pipeline,

    bool suppress_warnings,

    bool will_retry)

{

    std::unique_ptr<Pipeline> to_delete;

    if (encp->encrypted) {

        decryptStream(

            encp, file, qpdf_for_warning, pipeline, og, stream_dict, is_root_metadata, to_delete);

    }

    bool attempted_finish = false;

    try {

        auto buf = file->read(length, offset);

        if (buf.size() != length) {

            throw damagedPDF(

                *file, "", offset + toO(buf.size()), "unexpected EOF reading stream data");

        }

        pipeline->write(buf.data(), length);

        attempted_finish = true;

        pipeline->finish();

        return true;

    } catch (QPDFExc& e) {

        if (!suppress_warnings) {

            qpdf_for_warning.warn(e);

        }

    } catch (std::exception& e) {

        if (!suppress_warnings) {

            QTC::TC("qpdf", "QPDF decoding error warning");

            qpdf_for_warning.warn(

                // line-break

                damagedPDF(

                    *file,

                    "",

                    file->getLastOffset(),

                    ("error decoding stream data for object " + og.unparse(' ') + ": " +

                     e.what())));

            if (will_retry) {

                qpdf_for_warning.warn(

                    // line-break

                    damagedPDF(

                        *file,

                        "",

                        file->getLastOffset(),

                        "stream will be re-processed without filtering to avoid data loss"));

            }

        }

    }

    if (!attempted_finish) {

        try {

            pipeline->finish();

        } catch (std::exception&) {

            // ignore

        }

    }

    return false;

}

bool

QPDF::pipeStreamData(

    QPDFObjGen og,

    qpdf_offset_t offset,

    size_t length,

    QPDFObjectHandle stream_dict,

    bool is_root_metadata,

    Pipeline* pipeline,

    bool suppress_warnings,

    bool will_retry)

{

    return pipeStreamData(

        m->encp,

        m->file,

        *this,

        og,

        offset,

        length,

        stream_dict,

        is_root_metadata,

        pipeline,

        suppress_warnings,

        will_retry);

}

bool

QPDF::pipeForeignStreamData(

    std::shared_ptr<ForeignStreamData> foreign,

    Pipeline* pipeline,

    bool suppress_warnings,

    bool will_retry)

{

    if (foreign->encp->encrypted) {

        QTC::TC("qpdf", "QPDF pipe foreign encrypted stream");

    }

    return pipeStreamData(

        foreign->encp,

        foreign->file,

        *this,

        foreign->foreign_og,

        foreign->offset,

        foreign->length,

        foreign->local_dict,

        foreign->is_root_metadata,

        pipeline,

        suppress_warnings,

        will_retry);

}

// Throw a generic exception when we lack context for something more specific. New code should not

// use this. This method exists to improve somewhat from calling assert in very old code.

void

QPDF::stopOnError(std::string const& message)

{

    throw damagedPDF("", message);

}

// Return an exception of type qpdf_e_damaged_pdf.

QPDFExc

QPDF::damagedPDF(