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Use protozero lib to read geobuf (Initial implementation, not complete!)

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This commit is contained in:
artemp 2017-08-04 18:03:08 +01:00
parent dd507550c9
commit 3bbb5f413a
7 changed files with 124 additions and 296 deletions
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4
.gitmodules vendored
View file

@ -14,3 +14,7 @@
path = deps/mapbox/geometry path = deps/mapbox/geometry
url = https://github.com/mapbox/geometry.hpp.git url = https://github.com/mapbox/geometry.hpp.git
branch = master branch = master
[submodule "deps/mapbox/protozero"]
path = deps/mapbox/protozero
url = https://github.com/mapbox/protozero.git
branch = master

3
SConstruct
View file

@ -1,6 +1,6 @@
# This file is part of Mapnik (c++ mapping toolkit) # This file is part of Mapnik (c++ mapping toolkit)
# #
# Copyright (C) 2015 Artem Pavlenko # Copyright (C) 2017 Artem Pavlenko
# #
# Mapnik is free software; you can redistribute it and/or # Mapnik is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public # modify it under the terms of the GNU Lesser General Public
@ -1604,6 +1604,7 @@ if not preconfigured:
env.Prepend(LIBPATH = '#deps/agg') env.Prepend(LIBPATH = '#deps/agg')
env.Prepend(CPPPATH = '#deps/mapbox/variant/include') env.Prepend(CPPPATH = '#deps/mapbox/variant/include')
env.Prepend(CPPPATH = '#deps/mapbox/geometry/include') env.Prepend(CPPPATH = '#deps/mapbox/geometry/include')
env.Prepend(CPPPATH = '#deps/mapbox/protozero/include')
# prepend deps dir for auxillary headers # prepend deps dir for auxillary headers
env.Prepend(CPPPATH = '#deps') env.Prepend(CPPPATH = '#deps')

1
deps/mapbox/protozero vendored Submodule

@ -0,0 +1 @@
Subproject commit a1eb7327e853161e939a409a8d74a8302dd1ecc5

222
plugins/input/geobuf/geobuf.hpp
View file

@ -34,7 +34,7 @@
#include <vector> #include <vector>
#include <boost/optional.hpp> #include <boost/optional.hpp>
#include "pbf.hpp" #include <protozero/pbf_reader.hpp>
namespace mapnik { namespace util { namespace mapnik { namespace util {
@ -86,59 +86,59 @@ struct geobuf : mapnik::util::noncopyable
std::size_t lengths = 0; std::size_t lengths = 0;
std::vector<std::string> keys_; std::vector<std::string> keys_;
std::vector<value_type> values_; std::vector<value_type> values_;
mbgl::pbf pbf_; protozero::pbf_reader reader_;
FeatureCallback & callback_; FeatureCallback & callback_;
mapnik::context_ptr ctx_; mapnik::context_ptr ctx_;
const std::unique_ptr<mapnik::transcoder> tr_; const std::unique_ptr<mapnik::transcoder> tr_;
public: public:
//ctor //ctor
geobuf (unsigned char const* buf, std::size_t size, FeatureCallback & callback) geobuf (char const* buf, std::size_t size, FeatureCallback & callback)
: pbf_(buf, size), : reader_(buf, size),
callback_(callback), callback_(callback),
ctx_(std::make_shared<mapnik::context_type>()), ctx_(std::make_shared<mapnik::context_type>()),
tr_(new mapnik::transcoder("utf8")) {} tr_(new mapnik::transcoder("utf8")) {}
void read() void read()
{ {
while (pbf_.next()) while (reader_.next())
{ {
switch (pbf_.tag) switch (reader_.tag())
{ {
case 1: // keys case 1: // keys
{ {
keys_.push_back(pbf_.string()); keys_.push_back(reader_.get_string());
break; break;
} }
case 2: case 2:
{ {
dim = pbf_.varint(); dim = reader_.get_uint32();
break; break;
} }
case 3: case 3:
{ {
precision = std::pow(10,pbf_.varint()); precision = std::pow(10,reader_.get_uint32());
break; break;
} }
case 4: case 4:
{ {
auto feature_collection = pbf_.message(); auto feature_collection = reader_.get_message();
read_feature_collection(feature_collection); read_feature_collection(feature_collection);
break; break;
} }
case 6: case 6:
{ {
pbf_.message(); reader_.get_message();
MAPNIK_LOG_DEBUG(geobuf) << "standalone Geometry is not supported"; MAPNIK_LOG_DEBUG(geobuf) << "standalone Geometry is not supported";
break; break;
} }
case 7: case 7:
{ {
pbf_.message(); reader_.get_message();
MAPNIK_LOG_DEBUG(geobuf) << "Topology is not supported"; MAPNIK_LOG_DEBUG(geobuf) << "Topology is not supported";
break; break;
} }
default: default:
MAPNIK_LOG_DEBUG(geobuf) << "FIXME tag=" << pbf_.tag; MAPNIK_LOG_DEBUG(geobuf) << "Unsupported tag=" << reader_.tag();
break; break;
} }
} }
@ -152,40 +152,40 @@ private:
} }
template <typename T> template <typename T>
void read_value(T & pbf) void read_value(T & reader)
{ {
while (pbf.next()) while (reader.next())
{ {
switch (pbf.tag) switch (reader.tag())
{ {
case 1: case 1:
{ {
values_.emplace_back(pbf.string()); values_.emplace_back(reader.get_string());
break; break;
} }
case 2: case 2:
{ {
values_.emplace_back(pbf.float64()); values_.emplace_back(reader.get_double());
break; break;
} }
case 3: case 3:
{ {
values_.emplace_back(static_cast<int>(pbf.varint())); values_.emplace_back(static_cast<int>(reader.get_uint32()));
break; break;
} }
case 4: case 4:
{ {
values_.emplace_back(-static_cast<int>(pbf.varint())); values_.emplace_back(-static_cast<int>(reader.get_uint32()));
break; break;
} }
case 5: case 5:
{ {
values_.emplace_back(pbf.boolean()); values_.emplace_back(reader.get_bool());
break; break;
} }
case 6: case 6:
{ {
values_.emplace_back(pbf.string()); // JSON value values_.emplace_back(reader.get_string()); // JSON value
break; break;
} }
default: default:
@ -195,66 +195,69 @@ private:
} }
template <typename T, typename Feature> template <typename T, typename Feature>
void read_props(T & pbf, Feature & feature) void read_props(T & reader, Feature & feature)
{ {
std::uint8_t const* end = pbf.data + pbf.varint(); //char const* end = reader.get_data().first + reader.get_uint32();
while (pbf.data < end) auto pi = reader.get_packed_uint32();
for (auto it = pi.first; it != pi.second; ++it)
//while (reader.get_data().first < end)
{ {
auto key_index = pbf.varint(); auto key_index = *it++;
auto value_index = pbf.varint(); auto value_index = *it;
assert(key_index < keys_.size()); assert(key_index < keys_.size());
assert(value_index < values_.size()); assert(value_index< values_.size());
std::string const& name = keys_[key_index]; std::string const& name = keys_[key_index];
//std::cerr << "name:" << name << std::endl;
mapnik::util::apply_visitor(detail::value_visitor(feature, *tr_, name), values_[value_index]); mapnik::util::apply_visitor(detail::value_visitor(feature, *tr_, name), values_[value_index]);
} }
values_.clear(); values_.clear();
} }
template <typename T> template <typename T>
void read_feature (T & pbf) void read_feature (T & reader)
{ {
auto feature = feature_factory::create(ctx_,1); auto feature = feature_factory::create(ctx_,1);
while (pbf.next()) while (reader.next())
{ {
switch (pbf.tag) switch (reader.tag())
{ {
case 1: case 1:
{ {
auto message = pbf.message(); auto message = reader.get_message();
auto geom = read_geometry(message); auto geom = read_geometry(message);
feature->set_geometry(std::move(geom)); feature->set_geometry(std::move(geom));
break; break;
} }
case 11: case 11:
{ {
auto feature_id = pbf.string(); auto feature_id = reader.get_string();
break; break;
} }
case 12: case 12:
{ {
feature->set_id(pbf.template svarint<std::int64_t>()); feature->set_id(reader.get_sint64());
break; break;
} }
case 13: case 13:
{ {
auto message = pbf.message(); auto message = reader.get_message();
read_value(message); read_value(message);
break; break;
} }
case 14: case 14:
{ {
// feature props // feature props
read_props(pbf, *feature); read_props(reader, *feature);
break; break;
} }
case 15: case 15:
{ {
// generic props // generic props
read_props(pbf, *feature); read_props(reader, *feature);
break; break;
} }
default: default:
MAPNIK_LOG_DEBUG(geobuf) << "FAIL tag=" << pbf.tag; MAPNIK_LOG_DEBUG(geobuf) << "Unsupported tag=" << reader.tag();
break; break;
} }
} }
@ -262,27 +265,27 @@ private:
} }
template <typename T> template <typename T>
void read_feature_collection(T & pbf) void read_feature_collection(T & reader)
{ {
while (pbf.next()) while (reader.next())
{ {
switch (pbf.tag) switch (reader.tag())
{ {
case 1: case 1:
{ {
auto message = pbf.message(); auto message = reader.get_message();
read_feature(message); read_feature(message);
break; break;
} }
case 13: case 13:
{ {
auto message = pbf.message(); auto message = reader.get_message();
read_value(message); read_value(message);
break; break;
} }
case 15: case 15:
{ {
pbf.skipBytes(pbf.varint()); reader.skip();
break; break;
} }
default: default:
@ -292,15 +295,15 @@ private:
} }
template <typename T> template <typename T>
mapnik::geometry::point<double> read_point(T & pbf) mapnik::geometry::point<double> read_point(T & reader)
{ {
auto size = pbf.varint(); auto size = reader.get_uint32();
std::uint8_t const* end = pbf.data + size; char const* end = reader.get_data().first + size;
std::size_t count = 0; std::size_t count = 0;
double x, y; double x, y;
while (pbf.data < end) while (reader.get_data().first < end)
{ {
auto p = pbf.svarint(); auto p = reader.get_sint32();
auto index = count % dim; auto index = count % dim;
if ( index == 0) if ( index == 0)
{ {
@ -316,39 +319,39 @@ private:
} }
template <typename T> template <typename T>
mapnik::geometry::geometry<double> read_coords(T & pbf, geometry_type_e type, mapnik::geometry::geometry<double> read_coords(T & reader, geometry_type_e type,
boost::optional<std::vector<int>> const& lengths) boost::optional<std::vector<std::uint32_t>> const& lengths)
{ {
mapnik::geometry::geometry<double> geom = mapnik::geometry::geometry_empty(); mapnik::geometry::geometry<double> geom = mapnik::geometry::geometry_empty();
switch (type) switch (type)
{ {
case Point: case Point:
{ {
geom = read_point(pbf); geom = read_point(reader);
break; break;
} }
case Polygon: case Polygon:
{ {
geom = read_polygon(pbf, lengths); geom = read_polygon(reader, lengths);
break; break;
} }
case LineString: case LineString:
{ {
geom = read_line_string(pbf); geom = read_line_string(reader);
break; break;
} }
case MultiPoint: case MultiPoint:
{ {
geom = read_multi_point(pbf); geom = read_multi_point(reader);
break; break;
} }
case MultiLineString: case MultiLineString:
{ {
geom = read_multi_linestring(pbf, lengths); geom = read_multi_linestring(reader, lengths);
} }
case MultiPolygon: case MultiPolygon:
{ {
geom = read_multi_polygon(pbf, lengths); geom = read_multi_polygon(reader, lengths);
break; break;
} }
case GeometryCollection: case GeometryCollection:
@ -364,58 +367,59 @@ private:
} }
template <typename T> template <typename T>
std::vector<int> read_lengths(T & pbf) std::vector<std::uint32_t> read_lengths(T & reader)
{ {
std::vector<int> lengths; std::vector<std::uint32_t> lengths;
auto size = pbf.varint(); auto pi = reader.get_packed_uint32();
std::uint8_t const* end = pbf.data + size; for (auto it = pi.first; it != pi.second; ++it)
while (pbf.data < end)
{ {
lengths.push_back(pbf.varint()); lengths.push_back(*it);
} }
return lengths; return lengths;
} }
template <typename T, typename Ring> template <typename T, typename Iterator, typename Ring>
void read_linear_ring(T & pbf, int len, std::size_t size, Ring & ring, bool close = false) void read_linear_ring(T & reader, Iterator begin, Iterator end, Ring & ring, bool close = false)
{ {
int i = 0;
double x = 0.0; double x = 0.0;
double y = 0.0; double y = 0.0;
auto size = std::distance(begin, end);
ring.reserve(close ? size + 1 : size); ring.reserve(close ? size + 1 : size);
std::uint8_t const* end = pbf.data + size; std::size_t count = 0;
while ( (len > 0) ? i < len : pbf.data < end)
for (auto it = begin; it != end; ++it)
{ {
for (unsigned d = 0; d < dim; ++d) std::int64_t delta= *it;
auto d = count % dim;
if (d == 0) x += delta;
else if (d == 1)
{ {
std::int64_t delta = pbf.template svarint<std::int64_t>(); y += delta;
if (d == 0) x += delta; ring.emplace_back(transform(x), transform(y));
else if (d == 1) y += delta;
} }
ring.emplace_back(transform(x), transform(y)); //we're only interested in X and Y, ignoring any extra coordinates
++i; ++count;
} }
if (close && !ring.empty()) if (close && !ring.empty())
{ {
ring.emplace_back(ring.front()); ring.emplace_back(ring.front());
} }
} }
template <typename T> template <typename T>
mapnik::geometry::multi_point<double> read_multi_point(T & pbf) mapnik::geometry::multi_point<double> read_multi_point(T & reader)
{ {
mapnik::geometry::multi_point<double> multi_point; mapnik::geometry::multi_point<double> multi_point;
double x = 0.0; double x = 0.0;
double y = 0.0; double y = 0.0;
auto size = pbf.varint(); auto size = reader.get_uint32();
std::uint8_t const* end = pbf.data + size; char const* end = reader.get_data().first + size;
while (pbf.data < end) while (reader.get_data().first < end)
{ {
for (unsigned d = 0; d < dim; ++d) for (unsigned d = 0; d < dim; ++d)
{ {
if (d == 0) x += pbf.svarint(); if (d == 0) x += reader.get_int32();
else if (d == 1) y += pbf.svarint(); else if (d == 1) y += reader.get_int32();
} }
mapnik::geometry::point<double> pt(transform(x), transform(y)); mapnik::geometry::point<double> pt(transform(x), transform(y));
multi_point.push_back(std::move(pt)); multi_point.push_back(std::move(pt));
@ -424,25 +428,25 @@ private:
} }
template <typename T> template <typename T>
mapnik::geometry::line_string<double> read_line_string(T & pbf) mapnik::geometry::line_string<double> read_line_string(T & reader)
{ {
mapnik::geometry::line_string<double> line; mapnik::geometry::line_string<double> line;
auto size = pbf.varint(); auto pi = reader.get_packed_sint64();
read_linear_ring(pbf, 0, size, line); read_linear_ring(reader, pi.first, pi.second, line);
return line; return line;
} }
template <typename T> template <typename T>
mapnik::geometry::multi_line_string<double> read_multi_linestring(T & pbf, boost::optional<std::vector<int>> const& lengths) mapnik::geometry::multi_line_string<double> read_multi_linestring(T & reader, boost::optional<std::vector<std::uint32_t>> const& lengths)
{ {
mapnik::geometry::multi_line_string<double> multi_line; mapnik::geometry::multi_line_string<double> multi_line;
multi_line.reserve(!lengths ? 1 : lengths->size()); multi_line.reserve(!lengths ? 1 : lengths->size());
auto size = pbf.varint(); //auto size = reader.get_uint32();
if (!lengths) if (!lengths)
{ {
mapnik::geometry::line_string<double> line; mapnik::geometry::line_string<double> line;
read_linear_ring(pbf, 0, size, line); //read_linear_ring(reader, 0, size, line);
multi_line.push_back(std::move(line)); multi_line.push_back(std::move(line));
} }
else else
@ -450,7 +454,7 @@ private:
for (auto len : *lengths) for (auto len : *lengths)
{ {
mapnik::geometry::line_string<double> line; mapnik::geometry::line_string<double> line;
read_linear_ring(pbf, len, size, line); //read_linear_ring(reader, len, size, line);
multi_line.push_back(std::move(line)); multi_line.push_back(std::move(line));
} }
} }
@ -458,16 +462,15 @@ private:
} }
template <typename T> template <typename T>
mapnik::geometry::polygon<double> read_polygon(T & pbf, boost::optional<std::vector<int>> const& lengths) mapnik::geometry::polygon<double> read_polygon(T & reader, boost::optional<std::vector<std::uint32_t>> const& lengths)
{ {
mapnik::geometry::polygon<double> poly; mapnik::geometry::polygon<double> poly;
poly.reserve(!lengths ? 1 : lengths->size()); poly.reserve(!lengths ? 1 : lengths->size());
auto size = pbf.varint(); auto pi = reader.get_packed_sint64();
if (!lengths) if (!lengths)
{ {
mapnik::geometry::linear_ring<double> ring; mapnik::geometry::linear_ring<double> ring;
read_linear_ring(pbf, 0, size, ring, true); read_linear_ring(reader, pi.first, pi.second, ring, true);
poly.push_back(std::move(ring)); poly.push_back(std::move(ring));
} }
else else
@ -475,34 +478,37 @@ private:
for (auto len : *lengths) for (auto len : *lengths)
{ {
mapnik::geometry::linear_ring<double> ring; mapnik::geometry::linear_ring<double> ring;
read_linear_ring(pbf, len, size, ring, true); read_linear_ring(reader, pi.first, std::next(pi.first, dim * len), ring, true);
poly.push_back(std::move(ring)); poly.push_back(std::move(ring));
std::advance(pi.first, dim * len);
} }
} }
return poly; return poly;
} }
template <typename T> template <typename T>
mapnik::geometry::multi_polygon<double> read_multi_polygon(T & pbf, boost::optional<std::vector<int>> const& lengths) mapnik::geometry::multi_polygon<double> read_multi_polygon(T & reader, boost::optional<std::vector<std::uint32_t>> const& lengths)
{ {
mapnik::geometry::multi_polygon<double> multi_poly; mapnik::geometry::multi_polygon<double> multi_poly;
auto size = pbf.varint();
if (!lengths) if (!lengths)
{ {
auto poly = read_polygon(pbf, lengths); auto poly = read_polygon(reader, lengths);
multi_poly.push_back(std::move(poly)); multi_poly.push_back(std::move(poly));
} }
else if ((*lengths).size() > 0) else if ((*lengths).size() > 0)
{ {
int j = 1; int j = 1;
auto pi = reader.get_packed_sint64();
for (int i = 0; i < (*lengths)[0]; ++i) for (int i = 0; i < (*lengths)[0]; ++i)
{ {
mapnik::geometry::polygon<double> poly; mapnik::geometry::polygon<double> poly;
for (int k = 0; k < (*lengths)[j]; ++k) for (int k = 0; k < (*lengths)[j]; ++k)
{ {
mapnik::geometry::linear_ring<double> ring; mapnik::geometry::linear_ring<double> ring;
read_linear_ring(pbf, (*lengths)[j + 1 + k], size, ring, true); std::size_t len = dim * (*lengths)[j + k + 1];
read_linear_ring(reader, pi.first, std::next(pi.first, len), ring, true);
poly.push_back(std::move(ring)); poly.push_back(std::move(ring));
std::advance(pi.first, len);
} }
multi_poly.push_back(std::move(poly)); multi_poly.push_back(std::move(poly));
j += (*lengths)[j] + 1; j += (*lengths)[j] + 1;
@ -512,28 +518,28 @@ private:
} }
template <typename T> template <typename T>
mapnik::geometry::geometry<double> read_geometry(T & pbf) mapnik::geometry::geometry<double> read_geometry(T & reader)
{ {
mapnik::geometry::geometry<double> geom = mapnik::geometry::geometry_empty(); mapnik::geometry::geometry<double> geom = mapnik::geometry::geometry_empty();
geometry_type_e type = Unknown; geometry_type_e type = Unknown;
boost::optional<std::vector<int>> lengths; boost::optional<std::vector<std::uint32_t>> lengths;
while (pbf.next()) while (reader.next())
{ {
switch (pbf.tag) switch (reader.tag())
{ {
case 1: // type case 1: // type
{ {
type = static_cast<geometry_type_e>(pbf.varint()); type = static_cast<geometry_type_e>(reader.get_uint32());
break; break;
} }
case 2: case 2:
{ {
lengths = std::move(read_lengths(pbf)); lengths = std::move(read_lengths(reader));
break; break;
} }
case 3: case 3:
{ {
geom = std::move(read_coords(pbf, type, lengths)); geom = std::move(read_coords(reader, type, lengths));
break; break;
} }
case 4: case 4:
@ -543,26 +549,26 @@ private:
} }
case 11: case 11:
{ {
auto geom_id = pbf.string(); auto geom_id = reader.get_string();
MAPNIK_LOG_DEBUG(geobuf) << "geometry id's are not supported geom_id=" << geom_id ; MAPNIK_LOG_DEBUG(geobuf) << "geometry id's are not supported geom_id=" << geom_id ;
break; break;
} }
case 12: case 12:
{ {
auto geom_id = pbf.template varint<std::int64_t>(); auto geom_id = reader.get_int64();
MAPNIK_LOG_DEBUG(geobuf) << "geometry id's are not supported geom_id=" << geom_id ; MAPNIK_LOG_DEBUG(geobuf) << "geometry id's are not supported geom_id=" << geom_id ;
break; break;
} }
case 13: case 13:
{ {
auto value = pbf.message(); auto value = reader.get_message();
read_value(value); read_value(value);
break; break;
} }
case 14: case 14:
case 15: case 15:
{ {
pbf.skipBytes(pbf.varint()); reader.skip();
break; break;
} }
default: default:

4
plugins/input/geobuf/geobuf_datasource.cpp
View file

@ -114,7 +114,7 @@ geobuf_datasource::geobuf_datasource(parameters const& params)
{ {
throw mapnik::datasource_exception("Geobuf Plugin: could not open: '" + filename_ + "'"); throw mapnik::datasource_exception("Geobuf Plugin: could not open: '" + filename_ + "'");
} }
std::vector<std::uint8_t> geobuf; std::vector<char> geobuf;
geobuf.resize(in.size()); geobuf.resize(in.size());
std::fread(geobuf.data(), in.size(), 1, in.get()); std::fread(geobuf.data(), in.size(), 1, in.get());
parse_geobuf(geobuf.data(), geobuf.size()); parse_geobuf(geobuf.data(), geobuf.size());
@ -137,7 +137,7 @@ struct push_feature
} }
void geobuf_datasource::parse_geobuf(std::uint8_t const* data, std::size_t size) void geobuf_datasource::parse_geobuf(char const* data, std::size_t size)
{ {
using push_feature_callback = push_feature<std::vector<mapnik::feature_ptr>>; using push_feature_callback = push_feature<std::vector<mapnik::feature_ptr>>;
push_feature_callback callback(features_); push_feature_callback callback(features_);

2
plugins/input/geobuf/geobuf_datasource.hpp
View file

@ -90,7 +90,7 @@ public:
mapnik::box2d<double> envelope() const; mapnik::box2d<double> envelope() const;
mapnik::layer_descriptor get_descriptor() const; mapnik::layer_descriptor get_descriptor() const;
boost::optional<mapnik::datasource_geometry_t> get_geometry_type() const; boost::optional<mapnik::datasource_geometry_t> get_geometry_type() const;
void parse_geobuf(std::uint8_t const* buffer, std::size_t size); void parse_geobuf(char const* buffer, std::size_t size);
private: private:
mapnik::datasource::datasource_t type_; mapnik::datasource::datasource_t type_;
mapnik::layer_descriptor desc_; mapnik::layer_descriptor desc_;

184
plugins/input/geobuf/pbf.hpp
View file

@ -1,184 +0,0 @@
#ifndef MBGL_UTIL_PBF
#define MBGL_UTIL_PBF
/*
* Some parts are from upb - a minimalist implementation of protocol buffers.
*
* Copyright (c) 2008-2011 Google Inc. See LICENSE for details.
* Author: Josh Haberman <jhaberman@gmail.com>
*/
#include <string>
#include <cstring>
namespace mbgl {
struct pbf {
struct exception : std::exception { const char *what() const noexcept { return "pbf exception"; } };
struct unterminated_varint_exception : exception { const char *what() const noexcept { return "pbf unterminated varint exception"; } };
struct varint_too_long_exception : exception { const char *what() const noexcept { return "pbf varint too long exception"; } };
struct unknown_field_type_exception : exception { const char *what() const noexcept { return "pbf unknown field type exception"; } };
struct end_of_buffer_exception : exception { const char *what() const noexcept { return "pbf end of buffer exception"; } };
inline pbf(const unsigned char *data, size_t length);
inline pbf();
inline operator bool() const;
inline bool next();
inline bool next(uint32_t tag);
template <typename T = uint32_t> inline T varint();
template <typename T = uint32_t> inline T svarint();
template <typename T = uint32_t, int bytes = 4> inline T fixed();
inline float float32();
inline double float64();
inline std::string string();
inline bool boolean();
inline pbf message();
inline void skip();
inline void skipValue(uint32_t val);
inline void skipBytes(uint32_t bytes);
const uint8_t *data = nullptr;
const uint8_t *end = nullptr;
uint32_t value = 0;
uint32_t tag = 0;
};
pbf::pbf(const unsigned char *data_, size_t length)
: data(data_),
end(data_ + length),
value(0),
tag(0) {
}
pbf::pbf()
: data(nullptr),
end(nullptr),
value(0),
tag(0) {
}
pbf::operator bool() const {
return data < end;
}
bool pbf::next() {
if (data < end) {
value = static_cast<uint32_t>(varint());
tag = value >> 3;
return true;
}
return false;
}
bool pbf::next(uint32_t requested_tag) {
while (next()) {
if (tag == requested_tag) {
return true;
} else {
skip();
}
}
return false;
}
template <typename T>
T pbf::varint() {
uint8_t byte = 0x80;
T result = 0;
int bitpos;
for (bitpos = 0; bitpos < 70 && (byte & 0x80); bitpos += 7) {
if (data >= end) {
throw unterminated_varint_exception();
}
result |= ((T)(byte = *data) & 0x7F) << bitpos;
data++;
}
if (bitpos == 70 && (byte & 0x80)) {
throw varint_too_long_exception();
}
return result;
}
template <typename T>
T pbf::svarint() {
T n = varint<T>();
return (n >> 1) ^ -(T)(n & 1);
}
template <typename T, int bytes>
T pbf::fixed() {
skipBytes(bytes);
T result;
memcpy(&result, data - bytes, bytes);
return result;
}
float pbf::float32() {
return fixed<float, 4>();
}
double pbf::float64() {
return fixed<double, 8>();
}
std::string pbf::string() {
uint32_t bytes = static_cast<uint32_t>(varint());
const char *string_data = reinterpret_cast<const char*>(data);
skipBytes(bytes);
return std::string(string_data, bytes);
}
bool pbf::boolean() {
skipBytes(1);
return *(bool *)(data - 1);
}
pbf pbf::message() {
uint32_t bytes = static_cast<uint32_t>(varint());
const uint8_t *pos = data;
skipBytes(bytes);
return pbf(pos, bytes);
}
void pbf::skip() {
skipValue(value);
}
void pbf::skipValue(uint32_t val) {
switch (val & 0x7) {
case 0: // varint
varint();
break;
case 1: // 64 bit
skipBytes(8);
break;
case 2: // string/message
skipBytes(static_cast<uint32_t>(varint()));
break;
case 5: // 32 bit
skipBytes(4);
break;
default:
throw unknown_field_type_exception();
}
}
void pbf::skipBytes(uint32_t bytes) {
if (data + bytes > end) {
throw end_of_buffer_exception();
}
data += bytes;
}
} // end namespace mbgl
#endif