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/*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* Copyright (C) 2017, James R. Barlow (https://github.com/jbarlow83/)
*/
#include <sstream>
#include <pybind11/pybind11.h>
#include <pybind11/stl.h>
#include "pikepdf.h"
#include <qpdf/QPDFTokenizer.hh>
class PyParserCallbacks : public QPDFObjectHandle::ParserCallbacks {
public:
using QPDFObjectHandle::ParserCallbacks::ParserCallbacks;
virtual ~PyParserCallbacks() = default;
void handleObject(QPDFObjectHandle h) override {
PYBIND11_OVERLOAD_PURE_NAME(
void,
QPDFObjectHandle::ParserCallbacks,
"handle_object", /* Python name */
handleObject, /* C++ name */
h
);
}
void handleEOF() override {
PYBIND11_OVERLOAD_PURE_NAME(
void,
QPDFObjectHandle::ParserCallbacks,
"handle_eof", /* Python name */
handleEOF, /* C++ name; trailing comma needed for macro */
);
}
};
class OperandGrouper : public QPDFObjectHandle::ParserCallbacks {
public:
OperandGrouper(const std::string& operators)
: parsing_inline_image(false), count(0)
{
std::istringstream f(operators);
std::string s;
while (std::getline(f, s, ' ')) {
this->whitelist.insert(s);
}
}
void handleObject(QPDFObjectHandle obj) override
{
this->count++;
if (obj.getTypeCode() == QPDFObject::object_type_e::ot_operator) {
std::string op = obj.getOperatorValue();
// If we have a whitelist and this operator is not on the whitelist,
// discard it and all the tokens we collected
if (!this->whitelist.empty()) {
if (op[0] == 'q' || op[0] == 'Q') {
// We have token with multiple stack push/pops
if (this->whitelist.count("q") == 0 && this->whitelist.count("Q") == 0) {
this->tokens.clear();
return;
}
} else if (this->whitelist.count(op) == 0) {
this->tokens.clear();
return;
}
}
if (op == "BI") {
this->parsing_inline_image = true;
} else if (this->parsing_inline_image) {
if (op == "ID") {
this->inline_metadata = this->tokens;
} else if (op == "EI") {
auto PdfInlineImage = py::module::import("pikepdf").attr("PdfInlineImage");
auto kwargs = py::dict();
kwargs["image_data"] = this->tokens.at(0);
kwargs["image_object"] = this->inline_metadata;
auto iimage = PdfInlineImage(**kwargs);
// Package as list with single element for consistency
auto iimage_list = py::list();
iimage_list.append(iimage);
auto instruction = py::make_tuple(
iimage_list,
QPDFObjectHandle::newOperator("INLINE IMAGE")
);
this->instructions.append(instruction);
this->parsing_inline_image = false;
this->inline_metadata.clear();
}
} else {
py::list operand_list = py::cast(this->tokens);
auto instruction = py::make_tuple(operand_list, obj);
this->instructions.append(instruction);
}
this->tokens.clear();
} else {
this->tokens.push_back(obj);
}
}
void handleEOF() override
{
if (!this->tokens.empty())
this->warning = "Unexpected end of stream";
}
py::list getInstructions() const
{
return this->instructions;
}
std::string getWarning() const
{
return this->warning;
}
private:
std::set<std::string> whitelist;
std::vector<QPDFObjectHandle> tokens;
bool parsing_inline_image;
std::vector<QPDFObjectHandle> inline_metadata;
py::list instructions;
uint count;
std::string warning;
};
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