From 0f6a6bf30cd78b6338f0bd96ed1f1b6dbeb74816 Mon Sep 17 00:00:00 2001 From: Maxim Pimenov Date: Fri, 14 Feb 2020 17:43:43 +0300 Subject: [PATCH] [ge0] Allow other prefixes in Parser. For example, iOS emits "http://ge0.me/..." when sharing links to places but the parser could not handle this format. --- ge0/ge0_tests/parser_tests.cpp | 31 ++++++++++++++ ge0/parser.cpp | 78 +++++++++++++++++++++++----------- ge0/parser.hpp | 7 ++- 3 files changed, 90 insertions(+), 26 deletions(-) diff --git a/ge0/ge0_tests/parser_tests.cpp b/ge0/ge0_tests/parser_tests.cpp index 000b811a35..d3c4ceff1c 100644 --- a/ge0/ge0_tests/parser_tests.cpp +++ b/ge0/ge0_tests/parser_tests.cpp @@ -171,6 +171,11 @@ UNIT_TEST(LatLonDecoding) TestSuccess("ge0://B_________/Name", 90, 179.999999, 4.25, "Name"); TestSuccess("ge0://Bqqqqqqqqq/Name", 90, -180, 4.25, "Name"); TestSuccess("ge0://BAAAAAAAAA/Name", -90, -180, 4.25, "Name"); + TestFailure("ge0://Byqqqqqqq/Name"); + TestFailure("ge0://Byqqqqqqq/"); + TestFailure("ge0://Byqqqqqqq"); + TestFailure("ge0://B"); + TestFailure("ge0://"); } UNIT_TEST(NameDecoding) @@ -197,6 +202,12 @@ UNIT_TEST(NameDecoding) "\xd1\x81\xd1\x82\xd1\x80\xd0\xbe\xd0\xba\xd0\xb0_\xd0\xb2_\xd1\x8e\xd1\x82\xd1\x84-8", 0, 0, 4, "строка в ютф-8"); + TestSuccess("ge0://AwAAAAAAAA/", 0, 0, 4, ""); + TestSuccess("ge0://AwAAAAAAAA/s", 0, 0, 4, "s"); + + TestFailure("ge0://AwAAAAAAAAs"); + TestFailure("ge0://AwAAAAAAAAss"); + { auto const name = "Как вы считаете, надо ли писать const для параметров, которые передаются в функцию по " @@ -289,4 +300,24 @@ UNIT_TEST(ClippedName) TestSuccess("ge0://AwAAAAAAAA/" , 0, 0, 4, ""); TestSuccess("ge0://AwAAAAAAAA" , 0, 0, 4, ""); } + +UNIT_TEST(Bad_Base64) +{ + TestSuccess("ge0://Byqqqqqqqq", 45, 0, 4.25, ""); + TestFailure("ge0://Byqqqqqqq"); + TestFailure("ge0://Byqqqqqqq\xEE"); +} + +UNIT_TEST(OtherPrefixes) +{ + TestSuccess("http://ge0.me/Byqqqqqqqq/Name", 45, 0, 4.25, "Name"); + TestSuccess("https://ge0.me/Byqqqqqqqq/Name", 45, 0, 4.25, "Name"); + TestFailure("http://ge1.me/Byqqqqqqqq/Name"); + TestSuccess("http://ge0.me/AwAAAAAAAA/Super%5fPoi", 0, 0, 4, "Super Poi"); + TestSuccess("https://ge0.me/AwAAAAAAAA/Super%5fPoi", 0, 0, 4, "Super Poi"); + TestFailure("https://ge1.me/AwAAAAAAAA/Super%5fPoi"); + + TestSuccess("https://ge0.me/Byqqqqqqqq", 45, 0, 4.25, ""); + TestFailure("https://ge0.me/Byqqqqqqq"); +} } // namespace ge0 diff --git a/ge0/parser.cpp b/ge0/parser.cpp index 97ce8d51f2..53fbd0c04b 100644 --- a/ge0/parser.cpp +++ b/ge0/parser.cpp @@ -2,10 +2,11 @@ #include "ge0/url_generator.hpp" -#include "geometry/mercator.hpp" - #include "coding/url.hpp" +#include "geometry/mercator.hpp" + +#include "base/assert.hpp" #include "base/math.hpp" #include "base/string_utils.hpp" @@ -28,7 +29,7 @@ Ge0Parser::Ge0Parser() bool Ge0Parser::Parse(string const & url, double & outLat, double & outLon, std::string & outName, double & outZoomLevel) { - // URL format: + // Original URL format: // // +------------------ 1 byte: zoom level // |+-------+--------- 9 bytes: lat,lon @@ -36,30 +37,51 @@ bool Ge0Parser::Parse(string const & url, double & outLat, double & outLon, std: // || | | | // ge0://ZCoordba64/Name - const int ZOOM_POSITION = 6; - const int LATLON_POSITION = ZOOM_POSITION + 1; - const int NAME_POSITON_IN_URL = 17; - const int LATLON_LENGTH = NAME_POSITON_IN_URL - LATLON_POSITION - 1; - const size_t MAX_NAME_LENGTH = 256; + // Alternative format (differs only in the prefix): + // http://ge0.me/ZCoordba64/Name - if (url.size() < 16 || !strings::StartsWith(url, "ge0://")) + for (string const & prefix : {"ge0://", "http://ge0.me/", "https://ge0.me/"}) + { + if (strings::StartsWith(url, prefix)) + return ParseAfterPrefix(url, prefix.size(), outLat, outLon, outName, outZoomLevel); + } + + return false; +} + +bool Ge0Parser::ParseAfterPrefix(string const & url, size_t from, double & outLat, double & outLon, + std::string & outName, double & outZoomLevel) +{ + size_t const kEncodedZoomAndCoordinatesLength = 10; + if (url.size() < from + kEncodedZoomAndCoordinatesLength) return false; - uint8_t const zoomI = DecodeBase64Char(url[ZOOM_POSITION]); - if (zoomI > 63) + size_t const kMaxNameLength = 256; + + size_t const posZoom = from; + size_t const posLatLon = posZoom + 1; + size_t const posName = from + kEncodedZoomAndCoordinatesLength + 1; + size_t const lengthLatLon = posName - posLatLon - 1; + + uint8_t const zoomI = DecodeBase64Char(url[posZoom]); + if (zoomI >= 64) return false; outZoomLevel = DecodeZoom(zoomI); - DecodeLatLon(url.substr(LATLON_POSITION, LATLON_LENGTH), outLat, outLon); + if (!DecodeLatLon(url.substr(posLatLon, lengthLatLon), outLat, outLon)) + return false; ASSERT(mercator::ValidLon(outLon), (outLon)); ASSERT(mercator::ValidLat(outLat), (outLat)); - if (url.size() >= NAME_POSITON_IN_URL) + if (url.size() >= posName) { - outName = DecodeName( - url.substr(NAME_POSITON_IN_URL, min(url.size() - NAME_POSITON_IN_URL, MAX_NAME_LENGTH))); + CHECK_GREATER(posName, 0, ()); + if (url[posName - 1] != '/') + return false; + outName = DecodeName(url.substr(posName, min(url.size() - posName, kMaxNameLength))); } + return true; } @@ -74,28 +96,36 @@ double Ge0Parser::DecodeZoom(uint8_t const zoomByte) return static_cast(zoomByte) / 4 + 4; } -void Ge0Parser::DecodeLatLon(string const & url, double & lat, double & lon) +bool Ge0Parser::DecodeLatLon(string const & s, double & lat, double & lon) { - int latInt = 0, lonInt = 0; - DecodeLatLonToInt(url, latInt, lonInt, url.size()); + int latInt = 0; + int lonInt = 0; + if (!DecodeLatLonToInt(s, latInt, lonInt)) + return false; + lat = DecodeLatFromInt(latInt, (1 << kMaxCoordBits) - 1); lon = DecodeLonFromInt(lonInt, (1 << kMaxCoordBits) - 1); + return true; } -void Ge0Parser::DecodeLatLonToInt(string const & url, int & lat, int & lon, size_t const bytes) +bool Ge0Parser::DecodeLatLonToInt(string const & s, int & lat, int & lon) { int shift = kMaxCoordBits - 3; - for (size_t i = 0; i < bytes; ++i, shift -= 3) + for (size_t i = 0; i < s.size(); ++i, shift -= 3) { - const uint8_t a = DecodeBase64Char(url[i]); - const int lat1 = (((a >> 5) & 1) << 2 | ((a >> 3) & 1) << 1 | ((a >> 1) & 1)); - const int lon1 = (((a >> 4) & 1) << 2 | ((a >> 2) & 1) << 1 | (a & 1)); + uint8_t const a = DecodeBase64Char(s[i]); + if (a >= 64) + return false; + + int const lat1 = (((a >> 5) & 1) << 2 | ((a >> 3) & 1) << 1 | ((a >> 1) & 1)); + int const lon1 = (((a >> 4) & 1) << 2 | ((a >> 2) & 1) << 1 | (a & 1)); lat |= lat1 << shift; lon |= lon1 << shift; } - const double middleOfSquare = 1 << (3 * (kMaxPointBytes - bytes) - 1); + double const middleOfSquare = 1 << (3 * (kMaxPointBytes - s.size()) - 1); lat += middleOfSquare; lon += middleOfSquare; + return true; } double Ge0Parser::DecodeLatFromInt(int const lat, int const maxValue) diff --git a/ge0/parser.hpp b/ge0/parser.hpp index 0276d8565b..6120323b87 100644 --- a/ge0/parser.hpp +++ b/ge0/parser.hpp @@ -14,10 +14,13 @@ public: bool Parse(std::string const & url, double & outLat, double & outLon, std::string & outName, double & outZoomLevel); protected: + bool ParseAfterPrefix(std::string const & url, size_t from, double & outLat, double & outLon, + std::string & outName, double & outZoomLevel); + uint8_t DecodeBase64Char(char const c); static double DecodeZoom(uint8_t const zoomByte); - void DecodeLatLon(std::string const & url, double & lat, double & lon); - void DecodeLatLonToInt(std::string const & url, int & lat, int & lon, size_t const bytes); + bool DecodeLatLon(std::string const & s, double & lat, double & lon); + bool DecodeLatLonToInt(std::string const & s, int & lat, int & lon); double DecodeLatFromInt(int const lat, int const maxValue); double DecodeLonFromInt(int const lon, int const maxValue); std::string DecodeName(std::string name);