QPDFPageObjectHelper.cc
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#include <qpdf/QPDFPageObjectHelper.hh>
#include <qpdf/QTC.hh>
#include <qpdf/QPDF.hh>
QPDFPageObjectHelper::Members::~Members()
{
}
QPDFPageObjectHelper::Members::Members()
{
}
QPDFPageObjectHelper::QPDFPageObjectHelper(QPDFObjectHandle oh) :
QPDFObjectHelper(oh)
{
}
std::map<std::string, QPDFObjectHandle>
QPDFPageObjectHelper::getPageImages()
{
return this->oh.getPageImages();
}
std::vector<QPDFAnnotationObjectHelper>
QPDFPageObjectHelper::getAnnotations(std::string const& only_subtype)
{
std::vector<QPDFAnnotationObjectHelper> result;
QPDFObjectHandle annots = this->oh.getKey("/Annots");
if (annots.isArray())
{
size_t nannots = annots.getArrayNItems();
for (size_t i = 0; i < nannots; ++i)
{
QPDFObjectHandle annot = annots.getArrayItem(i);
if (only_subtype.empty() ||
(annot.isDictionary() &&
annot.getKey("/Subtype").isName() &&
(only_subtype == annot.getKey("/Subtype").getName())))
{
result.push_back(QPDFAnnotationObjectHelper(annot));
}
}
}
return result;
}
std::vector<QPDFObjectHandle>
QPDFPageObjectHelper::getPageContents()
{
return this->oh.getPageContents();
}
void
QPDFPageObjectHelper::addPageContents(QPDFObjectHandle contents, bool first)
{
this->oh.addPageContents(contents, first);
}
void
QPDFPageObjectHelper::rotatePage(int angle, bool relative)
{
this->oh.rotatePage(angle, relative);
}
void
QPDFPageObjectHelper::coalesceContentStreams()
{
this->oh.coalesceContentStreams();
}
void
QPDFPageObjectHelper::parsePageContents(
QPDFObjectHandle::ParserCallbacks* callbacks)
{
this->oh.parsePageContents(callbacks);
}
void
QPDFPageObjectHelper::filterPageContents(
QPDFObjectHandle::TokenFilter* filter,
Pipeline* next)
{
this->oh.filterPageContents(filter, next);
}
void
QPDFPageObjectHelper::pipePageContents(Pipeline* p)
{
this->oh.pipePageContents(p);
}
void
QPDFPageObjectHelper::addContentTokenFilter(
PointerHolder<QPDFObjectHandle::TokenFilter> token_filter)
{
this->oh.addContentTokenFilter(token_filter);
}
class NameWatcher: public QPDFObjectHandle::TokenFilter
{
public:
virtual ~NameWatcher()
{
}
virtual void handleToken(QPDFTokenizer::Token const&);
std::set<std::string> names;
};
void
NameWatcher::handleToken(QPDFTokenizer::Token const& token)
{
if (token.getType() == QPDFTokenizer::tt_name)
{
// Create a name object and get its name. This canonicalizes
// the representation of the name
this->names.insert(
QPDFObjectHandle::newName(token.getValue()).getName());
}
writeToken(token);
}
void
QPDFPageObjectHelper::removeUnreferencedResources()
{
NameWatcher nw;
try
{
filterPageContents(&nw);
}
catch (std::exception& e)
{
this->oh.warnIfPossible(
std::string("Unable to parse content stream: ") + e.what() +
"; not attempting to remove unreferenced objects from this page");
return;
}
// Walk through /Font and /XObject dictionaries, removing any
// resources that are not referenced. We must make copies of
// resource dictionaries down into the dictionaries are mutating
// to prevent mutating one dictionary from having the side effect
// of mutating the one it was copied from.
std::vector<std::string> to_filter;
to_filter.push_back("/Font");
to_filter.push_back("/XObject");
QPDFObjectHandle resources = this->oh.getKey("/Resources");
if (resources.isDictionary())
{
resources = resources.shallowCopy();
this->oh.replaceKey("/Resources", resources);
}
for (std::vector<std::string>::iterator d_iter = to_filter.begin();
d_iter != to_filter.end(); ++d_iter)
{
QPDFObjectHandle dict = resources.getKey(*d_iter);
if (! dict.isDictionary())
{
continue;
}
resources.replaceKey(*d_iter, dict);
std::set<std::string> keys = dict.getKeys();
for (std::set<std::string>::iterator k_iter = keys.begin();
k_iter != keys.end(); ++k_iter)
{
if (! nw.names.count(*k_iter))
{
dict.removeKey(*k_iter);
}
}
}
}
QPDFPageObjectHelper
QPDFPageObjectHelper::shallowCopyPage()
{
QPDF* qpdf = this->oh.getOwningQPDF();
if (! qpdf)
{
throw std::runtime_error(
"QPDFPageObjectHelper::shallowCopyPage"
" called with a direct objet");
}
QPDFObjectHandle new_page = this->oh.shallowCopy();
return QPDFPageObjectHelper(qpdf->makeIndirectObject(new_page));
}