diff options
Diffstat (limited to '')
-rw-r--r-- | external/CMakeLists.txt | 1 | ||||
-rw-r--r-- | external/qrcodegen/CMakeLists.txt | 7 | ||||
-rw-r--r-- | external/qrcodegen/QrCode.cpp | 862 | ||||
-rw-r--r-- | external/qrcodegen/QrCode.hpp | 556 |
4 files changed, 1426 insertions, 0 deletions
diff --git a/external/CMakeLists.txt b/external/CMakeLists.txt index 71b165f4f..a8916a7d0 100644 --- a/external/CMakeLists.txt +++ b/external/CMakeLists.txt @@ -80,4 +80,5 @@ endif() add_subdirectory(db_drivers) add_subdirectory(easylogging++) +add_subdirectory(qrcodegen) add_subdirectory(randomx EXCLUDE_FROM_ALL) diff --git a/external/qrcodegen/CMakeLists.txt b/external/qrcodegen/CMakeLists.txt new file mode 100644 index 000000000..a9060e3e8 --- /dev/null +++ b/external/qrcodegen/CMakeLists.txt @@ -0,0 +1,7 @@ +project(libqrcodegen) + +add_library(qrcodegen STATIC QrCode.cpp) +set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIC") + +target_include_directories(qrcodegen PUBLIC + ${CMAKE_CURRENT_SOURCE_DIR}) diff --git a/external/qrcodegen/QrCode.cpp b/external/qrcodegen/QrCode.cpp new file mode 100644 index 000000000..b9de86215 --- /dev/null +++ b/external/qrcodegen/QrCode.cpp @@ -0,0 +1,862 @@ +/* + * QR Code generator library (C++) + * + * Copyright (c) Project Nayuki. (MIT License) + * https://www.nayuki.io/page/qr-code-generator-library + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of + * this software and associated documentation files (the "Software"), to deal in + * the Software without restriction, including without limitation the rights to + * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of + * the Software, and to permit persons to whom the Software is furnished to do so, + * subject to the following conditions: + * - The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * - The Software is provided "as is", without warranty of any kind, express or + * implied, including but not limited to the warranties of merchantability, + * fitness for a particular purpose and noninfringement. In no event shall the + * authors or copyright holders be liable for any claim, damages or other + * liability, whether in an action of contract, tort or otherwise, arising from, + * out of or in connection with the Software or the use or other dealings in the + * Software. + */ + +#include <algorithm> +#include <climits> +#include <cstddef> +#include <cstdlib> +#include <cstring> +#include <sstream> +#include <stdexcept> +#include <utility> +#include "QrCode.hpp" + +using std::int8_t; +using std::uint8_t; +using std::size_t; +using std::vector; + + +namespace qrcodegen { + +QrSegment::Mode::Mode(int mode, int cc0, int cc1, int cc2) : + modeBits(mode) { + numBitsCharCount[0] = cc0; + numBitsCharCount[1] = cc1; + numBitsCharCount[2] = cc2; +} + + +int QrSegment::Mode::getModeBits() const { + return modeBits; +} + + +int QrSegment::Mode::numCharCountBits(int ver) const { + return numBitsCharCount[(ver + 7) / 17]; +} + + +const QrSegment::Mode QrSegment::Mode::NUMERIC (0x1, 10, 12, 14); +const QrSegment::Mode QrSegment::Mode::ALPHANUMERIC(0x2, 9, 11, 13); +const QrSegment::Mode QrSegment::Mode::BYTE (0x4, 8, 16, 16); +const QrSegment::Mode QrSegment::Mode::KANJI (0x8, 8, 10, 12); +const QrSegment::Mode QrSegment::Mode::ECI (0x7, 0, 0, 0); + + +QrSegment QrSegment::makeBytes(const vector<uint8_t> &data) { + if (data.size() > static_cast<unsigned int>(INT_MAX)) + throw std::length_error("Data too long"); + BitBuffer bb; + for (uint8_t b : data) + bb.appendBits(b, 8); + return QrSegment(Mode::BYTE, static_cast<int>(data.size()), std::move(bb)); +} + + +QrSegment QrSegment::makeNumeric(const char *digits) { + BitBuffer bb; + int accumData = 0; + int accumCount = 0; + int charCount = 0; + for (; *digits != '\0'; digits++, charCount++) { + char c = *digits; + if (c < '0' || c > '9') + throw std::domain_error("String contains non-numeric characters"); + accumData = accumData * 10 + (c - '0'); + accumCount++; + if (accumCount == 3) { + bb.appendBits(static_cast<uint32_t>(accumData), 10); + accumData = 0; + accumCount = 0; + } + } + if (accumCount > 0) // 1 or 2 digits remaining + bb.appendBits(static_cast<uint32_t>(accumData), accumCount * 3 + 1); + return QrSegment(Mode::NUMERIC, charCount, std::move(bb)); +} + + +QrSegment QrSegment::makeAlphanumeric(const char *text) { + BitBuffer bb; + int accumData = 0; + int accumCount = 0; + int charCount = 0; + for (; *text != '\0'; text++, charCount++) { + const char *temp = std::strchr(ALPHANUMERIC_CHARSET, *text); + if (temp == nullptr) + throw std::domain_error("String contains unencodable characters in alphanumeric mode"); + accumData = accumData * 45 + static_cast<int>(temp - ALPHANUMERIC_CHARSET); + accumCount++; + if (accumCount == 2) { + bb.appendBits(static_cast<uint32_t>(accumData), 11); + accumData = 0; + accumCount = 0; + } + } + if (accumCount > 0) // 1 character remaining + bb.appendBits(static_cast<uint32_t>(accumData), 6); + return QrSegment(Mode::ALPHANUMERIC, charCount, std::move(bb)); +} + + +vector<QrSegment> QrSegment::makeSegments(const char *text) { + // Select the most efficient segment encoding automatically + vector<QrSegment> result; + if (*text == '\0'); // Leave result empty + else if (isNumeric(text)) + result.push_back(makeNumeric(text)); + else if (isAlphanumeric(text)) + result.push_back(makeAlphanumeric(text)); + else { + vector<uint8_t> bytes; + for (; *text != '\0'; text++) + bytes.push_back(static_cast<uint8_t>(*text)); + result.push_back(makeBytes(bytes)); + } + return result; +} + + +QrSegment QrSegment::makeEci(long assignVal) { + BitBuffer bb; + if (assignVal < 0) + throw std::domain_error("ECI assignment value out of range"); + else if (assignVal < (1 << 7)) + bb.appendBits(static_cast<uint32_t>(assignVal), 8); + else if (assignVal < (1 << 14)) { + bb.appendBits(2, 2); + bb.appendBits(static_cast<uint32_t>(assignVal), 14); + } else if (assignVal < 1000000L) { + bb.appendBits(6, 3); + bb.appendBits(static_cast<uint32_t>(assignVal), 21); + } else + throw std::domain_error("ECI assignment value out of range"); + return QrSegment(Mode::ECI, 0, std::move(bb)); +} + + +QrSegment::QrSegment(Mode md, int numCh, const std::vector<bool> &dt) : + mode(md), + numChars(numCh), + data(dt) { + if (numCh < 0) + throw std::domain_error("Invalid value"); +} + + +QrSegment::QrSegment(Mode md, int numCh, std::vector<bool> &&dt) : + mode(md), + numChars(numCh), + data(std::move(dt)) { + if (numCh < 0) + throw std::domain_error("Invalid value"); +} + + +int QrSegment::getTotalBits(const vector<QrSegment> &segs, int version) { + int result = 0; + for (const QrSegment &seg : segs) { + int ccbits = seg.mode.numCharCountBits(version); + if (seg.numChars >= (1L << ccbits)) + return -1; // The segment's length doesn't fit the field's bit width + if (4 + ccbits > INT_MAX - result) + return -1; // The sum will overflow an int type + result += 4 + ccbits; + if (seg.data.size() > static_cast<unsigned int>(INT_MAX - result)) + return -1; // The sum will overflow an int type + result += static_cast<int>(seg.data.size()); + } + return result; +} + + +bool QrSegment::isAlphanumeric(const char *text) { + for (; *text != '\0'; text++) { + if (std::strchr(ALPHANUMERIC_CHARSET, *text) == nullptr) + return false; + } + return true; +} + + +bool QrSegment::isNumeric(const char *text) { + for (; *text != '\0'; text++) { + char c = *text; + if (c < '0' || c > '9') + return false; + } + return true; +} + + +QrSegment::Mode QrSegment::getMode() const { + return mode; +} + + +int QrSegment::getNumChars() const { + return numChars; +} + + +const std::vector<bool> &QrSegment::getData() const { + return data; +} + + +const char *QrSegment::ALPHANUMERIC_CHARSET = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ $%*+-./:"; + + + +int QrCode::getFormatBits(Ecc ecl) { + switch (ecl) { + case Ecc::LOW : return 1; + case Ecc::MEDIUM : return 0; + case Ecc::QUARTILE: return 3; + case Ecc::HIGH : return 2; + default: throw std::logic_error("Assertion error"); + } +} + + +QrCode QrCode::encodeText(const char *text, Ecc ecl) { + vector<QrSegment> segs = QrSegment::makeSegments(text); + return encodeSegments(segs, ecl); +} + + +QrCode QrCode::encodeBinary(const vector<uint8_t> &data, Ecc ecl) { + vector<QrSegment> segs{QrSegment::makeBytes(data)}; + return encodeSegments(segs, ecl); +} + + +QrCode QrCode::encodeSegments(const vector<QrSegment> &segs, Ecc ecl, + int minVersion, int maxVersion, int mask, bool boostEcl) { + if (!(MIN_VERSION <= minVersion && minVersion <= maxVersion && maxVersion <= MAX_VERSION) || mask < -1 || mask > 7) + throw std::invalid_argument("Invalid value"); + + // Find the minimal version number to use + int version, dataUsedBits; + for (version = minVersion; ; version++) { + int dataCapacityBits = getNumDataCodewords(version, ecl) * 8; // Number of data bits available + dataUsedBits = QrSegment::getTotalBits(segs, version); + if (dataUsedBits != -1 && dataUsedBits <= dataCapacityBits) + break; // This version number is found to be suitable + if (version >= maxVersion) { // All versions in the range could not fit the given data + std::ostringstream sb; + if (dataUsedBits == -1) + sb << "Segment too long"; + else { + sb << "Data length = " << dataUsedBits << " bits, "; + sb << "Max capacity = " << dataCapacityBits << " bits"; + } + throw data_too_long(sb.str()); + } + } + if (dataUsedBits == -1) + throw std::logic_error("Assertion error"); + + // Increase the error correction level while the data still fits in the current version number + for (Ecc newEcl : vector<Ecc>{Ecc::MEDIUM, Ecc::QUARTILE, Ecc::HIGH}) { // From low to high + if (boostEcl && dataUsedBits <= getNumDataCodewords(version, newEcl) * 8) + ecl = newEcl; + } + + // Concatenate all segments to create the data bit string + BitBuffer bb; + for (const QrSegment &seg : segs) { + bb.appendBits(static_cast<uint32_t>(seg.getMode().getModeBits()), 4); + bb.appendBits(static_cast<uint32_t>(seg.getNumChars()), seg.getMode().numCharCountBits(version)); + bb.insert(bb.end(), seg.getData().begin(), seg.getData().end()); + } + if (bb.size() != static_cast<unsigned int>(dataUsedBits)) + throw std::logic_error("Assertion error"); + + // Add terminator and pad up to a byte if applicable + size_t dataCapacityBits = static_cast<size_t>(getNumDataCodewords(version, ecl)) * 8; + if (bb.size() > dataCapacityBits) + throw std::logic_error("Assertion error"); + bb.appendBits(0, std::min(4, static_cast<int>(dataCapacityBits - bb.size()))); + bb.appendBits(0, (8 - static_cast<int>(bb.size() % 8)) % 8); + if (bb.size() % 8 != 0) + throw std::logic_error("Assertion error"); + + // Pad with alternating bytes until data capacity is reached + for (uint8_t padByte = 0xEC; bb.size() < dataCapacityBits; padByte ^= 0xEC ^ 0x11) + bb.appendBits(padByte, 8); + + // Pack bits into bytes in big endian + vector<uint8_t> dataCodewords(bb.size() / 8); + for (size_t i = 0; i < bb.size(); i++) + dataCodewords[i >> 3] |= (bb.at(i) ? 1 : 0) << (7 - (i & 7)); + + // Create the QR Code object + return QrCode(version, ecl, dataCodewords, mask); +} + + +QrCode::QrCode(int ver, Ecc ecl, const vector<uint8_t> &dataCodewords, int msk) : + // Initialize fields and check arguments + version(ver), + errorCorrectionLevel(ecl) { + if (ver < MIN_VERSION || ver > MAX_VERSION) + throw std::domain_error("Version value out of range"); + if (msk < -1 || msk > 7) + throw std::domain_error("Mask value out of range"); + size = ver * 4 + 17; + size_t sz = static_cast<size_t>(size); + modules = vector<vector<bool> >(sz, vector<bool>(sz)); // Initially all white + isFunction = vector<vector<bool> >(sz, vector<bool>(sz)); + + // Compute ECC, draw modules + drawFunctionPatterns(); + const vector<uint8_t> allCodewords = addEccAndInterleave(dataCodewords); + drawCodewords(allCodewords); + + // Do masking + if (msk == -1) { // Automatically choose best mask + long minPenalty = LONG_MAX; + for (int i = 0; i < 8; i++) { + applyMask(i); + drawFormatBits(i); + long penalty = getPenaltyScore(); + if (penalty < minPenalty) { + msk = i; + minPenalty = penalty; + } + applyMask(i); // Undoes the mask due to XOR + } + } + if (msk < 0 || msk > 7) + throw std::logic_error("Assertion error"); + this->mask = msk; + applyMask(msk); // Apply the final choice of mask + drawFormatBits(msk); // Overwrite old format bits + + isFunction.clear(); + isFunction.shrink_to_fit(); +} + + +int QrCode::getVersion() const { + return version; +} + + +int QrCode::getSize() const { + return size; +} + + +QrCode::Ecc QrCode::getErrorCorrectionLevel() const { + return errorCorrectionLevel; +} + + +int QrCode::getMask() const { + return mask; +} + + +bool QrCode::getModule(int x, int y) const { + return 0 <= x && x < size && 0 <= y && y < size && module(x, y); +} + + +std::string QrCode::toSvgString(int border) const { + if (border < 0) + throw std::domain_error("Border must be non-negative"); + if (border > INT_MAX / 2 || border * 2 > INT_MAX - size) + throw std::overflow_error("Border too large"); + + std::ostringstream sb; + sb << "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"; + sb << "<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\" \"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\">\n"; + sb << "<svg xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\" viewBox=\"0 0 "; + sb << (size + border * 2) << " " << (size + border * 2) << "\" stroke=\"none\">\n"; + sb << "\t<rect width=\"100%\" height=\"100%\" fill=\"#FFFFFF\"/>\n"; + sb << "\t<path d=\""; + for (int y = 0; y < size; y++) { + for (int x = 0; x < size; x++) { + if (getModule(x, y)) { + if (x != 0 || y != 0) + sb << " "; + sb << "M" << (x + border) << "," << (y + border) << "h1v1h-1z"; + } + } + } + sb << "\" fill=\"#000000\"/>\n"; + sb << "</svg>\n"; + return sb.str(); +} + + +void QrCode::drawFunctionPatterns() { + // Draw horizontal and vertical timing patterns + for (int i = 0; i < size; i++) { + setFunctionModule(6, i, i % 2 == 0); + setFunctionModule(i, 6, i % 2 == 0); + } + + // Draw 3 finder patterns (all corners except bottom right; overwrites some timing modules) + drawFinderPattern(3, 3); + drawFinderPattern(size - 4, 3); + drawFinderPattern(3, size - 4); + + // Draw numerous alignment patterns + const vector<int> alignPatPos = getAlignmentPatternPositions(); + size_t numAlign = alignPatPos.size(); + for (size_t i = 0; i < numAlign; i++) { + for (size_t j = 0; j < numAlign; j++) { + // Don't draw on the three finder corners + if (!((i == 0 && j == 0) || (i == 0 && j == numAlign - 1) || (i == numAlign - 1 && j == 0))) + drawAlignmentPattern(alignPatPos.at(i), alignPatPos.at(j)); + } + } + + // Draw configuration data + drawFormatBits(0); // Dummy mask value; overwritten later in the constructor + drawVersion(); +} + + +void QrCode::drawFormatBits(int msk) { + // Calculate error correction code and pack bits + int data = getFormatBits(errorCorrectionLevel) << 3 | msk; // errCorrLvl is uint2, msk is uint3 + int rem = data; + for (int i = 0; i < 10; i++) + rem = (rem << 1) ^ ((rem >> 9) * 0x537); + int bits = (data << 10 | rem) ^ 0x5412; // uint15 + if (bits >> 15 != 0) + throw std::logic_error("Assertion error"); + + // Draw first copy + for (int i = 0; i <= 5; i++) + setFunctionModule(8, i, getBit(bits, i)); + setFunctionModule(8, 7, getBit(bits, 6)); + setFunctionModule(8, 8, getBit(bits, 7)); + setFunctionModule(7, 8, getBit(bits, 8)); + for (int i = 9; i < 15; i++) + setFunctionModule(14 - i, 8, getBit(bits, i)); + + // Draw second copy + for (int i = 0; i < 8; i++) + setFunctionModule(size - 1 - i, 8, getBit(bits, i)); + for (int i = 8; i < 15; i++) + setFunctionModule(8, size - 15 + i, getBit(bits, i)); + setFunctionModule(8, size - 8, true); // Always black +} + + +void QrCode::drawVersion() { + if (version < 7) + return; + + // Calculate error correction code and pack bits + int rem = version; // version is uint6, in the range [7, 40] + for (int i = 0; i < 12; i++) + rem = (rem << 1) ^ ((rem >> 11) * 0x1F25); + long bits = static_cast<long>(version) << 12 | rem; // uint18 + if (bits >> 18 != 0) + throw std::logic_error("Assertion error"); + + // Draw two copies + for (int i = 0; i < 18; i++) { + bool bit = getBit(bits, i); + int a = size - 11 + i % 3; + int b = i / 3; + setFunctionModule(a, b, bit); + setFunctionModule(b, a, bit); + } +} + + +void QrCode::drawFinderPattern(int x, int y) { + for (int dy = -4; dy <= 4; dy++) { + for (int dx = -4; dx <= 4; dx++) { + int dist = std::max(std::abs(dx), std::abs(dy)); // Chebyshev/infinity norm + int xx = x + dx, yy = y + dy; + if (0 <= xx && xx < size && 0 <= yy && yy < size) + setFunctionModule(xx, yy, dist != 2 && dist != 4); + } + } +} + + +void QrCode::drawAlignmentPattern(int x, int y) { + for (int dy = -2; dy <= 2; dy++) { + for (int dx = -2; dx <= 2; dx++) + setFunctionModule(x + dx, y + dy, std::max(std::abs(dx), std::abs(dy)) != 1); + } +} + + +void QrCode::setFunctionModule(int x, int y, bool isBlack) { + size_t ux = static_cast<size_t>(x); + size_t uy = static_cast<size_t>(y); + modules .at(uy).at(ux) = isBlack; + isFunction.at(uy).at(ux) = true; +} + + +bool QrCode::module(int x, int y) const { + return modules.at(static_cast<size_t>(y)).at(static_cast<size_t>(x)); +} + + +vector<uint8_t> QrCode::addEccAndInterleave(const vector<uint8_t> &data) const { + if (data.size() != static_cast<unsigned int>(getNumDataCodewords(version, errorCorrectionLevel))) + throw std::invalid_argument("Invalid argument"); + + // Calculate parameter numbers + int numBlocks = NUM_ERROR_CORRECTION_BLOCKS[static_cast<int>(errorCorrectionLevel)][version]; + int blockEccLen = ECC_CODEWORDS_PER_BLOCK [static_cast<int>(errorCorrectionLevel)][version]; + int rawCodewords = getNumRawDataModules(version) / 8; + int numShortBlocks = numBlocks - rawCodewords % numBlocks; + int shortBlockLen = rawCodewords / numBlocks; + + // Split data into blocks and append ECC to each block + vector<vector<uint8_t> > blocks; + const vector<uint8_t> rsDiv = reedSolomonComputeDivisor(blockEccLen); + for (int i = 0, k = 0; i < numBlocks; i++) { + vector<uint8_t> dat(data.cbegin() + k, data.cbegin() + (k + shortBlockLen - blockEccLen + (i < numShortBlocks ? 0 : 1))); + k += static_cast<int>(dat.size()); + const vector<uint8_t> ecc = reedSolomonComputeRemainder(dat, rsDiv); + if (i < numShortBlocks) + dat.push_back(0); + dat.insert(dat.end(), ecc.cbegin(), ecc.cend()); + blocks.push_back(std::move(dat)); + } + + // Interleave (not concatenate) the bytes from every block into a single sequence + vector<uint8_t> result; + for (size_t i = 0; i < blocks.at(0).size(); i++) { + for (size_t j = 0; j < blocks.size(); j++) { + // Skip the padding byte in short blocks + if (i != static_cast<unsigned int>(shortBlockLen - blockEccLen) || j >= static_cast<unsigned int>(numShortBlocks)) + result.push_back(blocks.at(j).at(i)); + } + } + if (result.size() != static_cast<unsigned int>(rawCodewords)) + throw std::logic_error("Assertion error"); + return result; +} + + +void QrCode::drawCodewords(const vector<uint8_t> &data) { + if (data.size() != static_cast<unsigned int>(getNumRawDataModules(version) / 8)) + throw std::invalid_argument("Invalid argument"); + + size_t i = 0; // Bit index into the data + // Do the funny zigzag scan + for (int right = size - 1; right >= 1; right -= 2) { // Index of right column in each column pair + if (right == 6) + right = 5; + for (int vert = 0; vert < size; vert++) { // Vertical counter + for (int j = 0; j < 2; j++) { + size_t x = static_cast<size_t>(right - j); // Actual x coordinate + bool upward = ((right + 1) & 2) == 0; + size_t y = static_cast<size_t>(upward ? size - 1 - vert : vert); // Actual y coordinate + if (!isFunction.at(y).at(x) && i < data.size() * 8) { + modules.at(y).at(x) = getBit(data.at(i >> 3), 7 - static_cast<int>(i & 7)); + i++; + } + // If this QR Code has any remainder bits (0 to 7), they were assigned as + // 0/false/white by the constructor and are left unchanged by this method + } + } + } + if (i != data.size() * 8) + throw std::logic_error("Assertion error"); +} + + +void QrCode::applyMask(int msk) { + if (msk < 0 || msk > 7) + throw std::domain_error("Mask value out of range"); + size_t sz = static_cast<size_t>(size); + for (size_t y = 0; y < sz; y++) { + for (size_t x = 0; x < sz; x++) { + bool invert; + switch (msk) { + case 0: invert = (x + y) % 2 == 0; break; + case 1: invert = y % 2 == 0; break; + case 2: invert = x % 3 == 0; break; + case 3: invert = (x + y) % 3 == 0; break; + case 4: invert = (x / 3 + y / 2) % 2 == 0; break; + case 5: invert = x * y % 2 + x * y % 3 == 0; break; + case 6: invert = (x * y % 2 + x * y % 3) % 2 == 0; break; + case 7: invert = ((x + y) % 2 + x * y % 3) % 2 == 0; break; + default: throw std::logic_error("Assertion error"); + } + modules.at(y).at(x) = modules.at(y).at(x) ^ (invert & !isFunction.at(y).at(x)); + } + } +} + + +long QrCode::getPenaltyScore() const { + long result = 0; + + // Adjacent modules in row having same color, and finder-like patterns + for (int y = 0; y < size; y++) { + bool runColor = false; + int runX = 0; + std::array<int,7> runHistory = {}; + for (int x = 0; x < size; x++) { + if (module(x, y) == runColor) { + runX++; + if (runX == 5) + result += PENALTY_N1; + else if (runX > 5) + result++; + } else { + finderPenaltyAddHistory(runX, runHistory); + if (!runColor) + result += finderPenaltyCountPatterns(runHistory) * PENALTY_N3; + runColor = module(x, y); + runX = 1; + } + } + result += finderPenaltyTerminateAndCount(runColor, runX, runHistory) * PENALTY_N3; + } + // Adjacent modules in column having same color, and finder-like patterns + for (int x = 0; x < size; x++) { + bool runColor = false; + int runY = 0; + std::array<int,7> runHistory = {}; + for (int y = 0; y < size; y++) { + if (module(x, y) == runColor) { + runY++; + if (runY == 5) + result += PENALTY_N1; + else if (runY > 5) + result++; + } else { + finderPenaltyAddHistory(runY, runHistory); + if (!runColor) + result += finderPenaltyCountPatterns(runHistory) * PENALTY_N3; + runColor = module(x, y); + runY = 1; + } + } + result += finderPenaltyTerminateAndCount(runColor, runY, runHistory) * PENALTY_N3; + } + + // 2*2 blocks of modules having same color + for (int y = 0; y < size - 1; y++) { + for (int x = 0; x < size - 1; x++) { + bool color = module(x, y); + if ( color == module(x + 1, y) && + color == module(x, y + 1) && + color == module(x + 1, y + 1)) + result += PENALTY_N2; + } + } + + // Balance of black and white modules + int black = 0; + for (const vector<bool> &row : modules) { + for (bool color : row) { + if (color) + black++; + } + } + int total = size * size; // Note that size is odd, so black/total != 1/2 + // Compute the smallest integer k >= 0 such that (45-5k)% <= black/total <= (55+5k)% + int k = static_cast<int>((std::abs(black * 20L - total * 10L) + total - 1) / total) - 1; + result += k * PENALTY_N4; + return result; +} + + +vector<int> QrCode::getAlignmentPatternPositions() const { + if (version == 1) + return vector<int>(); + else { + int numAlign = version / 7 + 2; + int step = (version == 32) ? 26 : + (version*4 + numAlign*2 + 1) / (numAlign*2 - 2) * 2; + vector<int> result; + for (int i = 0, pos = size - 7; i < numAlign - 1; i++, pos -= step) + result.insert(result.begin(), pos); + result.insert(result.begin(), 6); + return result; + } +} + + +int QrCode::getNumRawDataModules(int ver) { + if (ver < MIN_VERSION || ver > MAX_VERSION) + throw std::domain_error("Version number out of range"); + int result = (16 * ver + 128) * ver + 64; + if (ver >= 2) { + int numAlign = ver / 7 + 2; + result -= (25 * numAlign - 10) * numAlign - 55; + if (ver >= 7) + result -= 36; + } + if (!(208 <= result && result <= 29648)) + throw std::logic_error("Assertion error"); + return result; +} + + +int QrCode::getNumDataCodewords(int ver, Ecc ecl) { + return getNumRawDataModules(ver) / 8 + - ECC_CODEWORDS_PER_BLOCK [static_cast<int>(ecl)][ver] + * NUM_ERROR_CORRECTION_BLOCKS[static_cast<int>(ecl)][ver]; +} + + +vector<uint8_t> QrCode::reedSolomonComputeDivisor(int degree) { + if (degree < 1 || degree > 255) + throw std::domain_error("Degree out of range"); + // Polynomial coefficients are stored from highest to lowest power, excluding the leading term which is always 1. + // For example the polynomial x^3 + 255x^2 + 8x + 93 is stored as the uint8 array {255, 8, 93}. + vector<uint8_t> result(static_cast<size_t>(degree)); + result.at(result.size() - 1) = 1; // Start off with the monomial x^0 + + // Compute the product polynomial (x - r^0) * (x - r^1) * (x - r^2) * ... * (x - r^{degree-1}), + // and drop the highest monomial term which is always 1x^degree. + // Note that r = 0x02, which is a generator element of this field GF(2^8/0x11D). + uint8_t root = 1; + for (int i = 0; i < degree; i++) { + // Multiply the current product by (x - r^i) + for (size_t j = 0; j < result.size(); j++) { + result.at(j) = reedSolomonMultiply(result.at(j), root); + if (j + 1 < result.size()) + result.at(j) ^= result.at(j + 1); + } + root = reedSolomonMultiply(root, 0x02); + } + return result; +} + + +vector<uint8_t> QrCode::reedSolomonComputeRemainder(const vector<uint8_t> &data, const vector<uint8_t> &divisor) { + vector<uint8_t> result(divisor.size()); + for (uint8_t b : data) { // Polynomial division + uint8_t factor = b ^ result.at(0); + result.erase(result.begin()); + result.push_back(0); + for (size_t i = 0; i < result.size(); i++) + result.at(i) ^= reedSolomonMultiply(divisor.at(i), factor); + } + return result; +} + + +uint8_t QrCode::reedSolomonMultiply(uint8_t x, uint8_t y) { + // Russian peasant multiplication + int z = 0; + for (int i = 7; i >= 0; i--) { + z = (z << 1) ^ ((z >> 7) * 0x11D); + z ^= ((y >> i) & 1) * x; + } + if (z >> 8 != 0) + throw std::logic_error("Assertion error"); + return static_cast<uint8_t>(z); +} + + +int QrCode::finderPenaltyCountPatterns(const std::array<int,7> &runHistory) const { + int n = runHistory.at(1); + if (n > size * 3) + throw std::logic_error("Assertion error"); + bool core = n > 0 && runHistory.at(2) == n && runHistory.at(3) == n * 3 && runHistory.at(4) == n && runHistory.at(5) == n; + return (core && runHistory.at(0) >= n * 4 && runHistory.at(6) >= n ? 1 : 0) + + (core && runHistory.at(6) >= n * 4 && runHistory.at(0) >= n ? 1 : 0); +} + + +int QrCode::finderPenaltyTerminateAndCount(bool currentRunColor, int currentRunLength, std::array<int,7> &runHistory) const { + if (currentRunColor) { // Terminate black run + finderPenaltyAddHistory(currentRunLength, runHistory); + currentRunLength = 0; + } + currentRunLength += size; // Add white border to final run + finderPenaltyAddHistory(currentRunLength, runHistory); + return finderPenaltyCountPatterns(runHistory); +} + + +void QrCode::finderPenaltyAddHistory(int currentRunLength, std::array<int,7> &runHistory) const { + if (runHistory.at(0) == 0) + currentRunLength += size; // Add white border to initial run + std::copy_backward(runHistory.cbegin(), runHistory.cend() - 1, runHistory.end()); + runHistory.at(0) = currentRunLength; +} + + +bool QrCode::getBit(long x, int i) { + return ((x >> i) & 1) != 0; +} + + +/*---- Tables of constants ----*/ + +const int QrCode::PENALTY_N1 = 3; +const int QrCode::PENALTY_N2 = 3; +const int QrCode::PENALTY_N3 = 40; +const int QrCode::PENALTY_N4 = 10; + + +const int8_t QrCode::ECC_CODEWORDS_PER_BLOCK[4][41] = { + // Version: (note that index 0 is for padding, and is set to an illegal value) + //0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40 Error correction level + {-1, 7, 10, 15, 20, 26, 18, 20, 24, 30, 18, 20, 24, 26, 30, 22, 24, 28, 30, 28, 28, 28, 28, 30, 30, 26, 28, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30}, // Low + {-1, 10, 16, 26, 18, 24, 16, 18, 22, 22, 26, 30, 22, 22, 24, 24, 28, 28, 26, 26, 26, 26, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28}, // Medium + {-1, 13, 22, 18, 26, 18, 24, 18, 22, 20, 24, 28, 26, 24, 20, 30, 24, 28, 28, 26, 30, 28, 30, 30, 30, 30, 28, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30}, // Quartile + {-1, 17, 28, 22, 16, 22, 28, 26, 26, 24, 28, 24, 28, 22, 24, 24, 30, 28, 28, 26, 28, 30, 24, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30}, // High +}; + +const int8_t QrCode::NUM_ERROR_CORRECTION_BLOCKS[4][41] = { + // Version: (note that index 0 is for padding, and is set to an illegal value) + //0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40 Error correction level + {-1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 4, 4, 4, 4, 4, 6, 6, 6, 6, 7, 8, 8, 9, 9, 10, 12, 12, 12, 13, 14, 15, 16, 17, 18, 19, 19, 20, 21, 22, 24, 25}, // Low + {-1, 1, 1, 1, 2, 2, 4, 4, 4, 5, 5, 5, 8, 9, 9, 10, 10, 11, 13, 14, 16, 17, 17, 18, 20, 21, 23, 25, 26, 28, 29, 31, 33, 35, 37, 38, 40, 43, 45, 47, 49}, // Medium + {-1, 1, 1, 2, 2, 4, 4, 6, 6, 8, 8, 8, 10, 12, 16, 12, 17, 16, 18, 21, 20, 23, 23, 25, 27, 29, 34, 34, 35, 38, 40, 43, 45, 48, 51, 53, 56, 59, 62, 65, 68}, // Quartile + {-1, 1, 1, 2, 4, 4, 4, 5, 6, 8, 8, 11, 11, 16, 16, 18, 16, 19, 21, 25, 25, 25, 34, 30, 32, 35, 37, 40, 42, 45, 48, 51, 54, 57, 60, 63, 66, 70, 74, 77, 81}, // High +}; + + +data_too_long::data_too_long(const std::string &msg) : + std::length_error(msg) {} + + + +BitBuffer::BitBuffer() + : std::vector<bool>() {} + + +void BitBuffer::appendBits(std::uint32_t val, int len) { + if (len < 0 || len > 31 || val >> len != 0) + throw std::domain_error("Value out of range"); + for (int i = len - 1; i >= 0; i--) // Append bit by bit + this->push_back(((val >> i) & 1) != 0); +} + +} diff --git a/external/qrcodegen/QrCode.hpp b/external/qrcodegen/QrCode.hpp new file mode 100644 index 000000000..7341e4102 --- /dev/null +++ b/external/qrcodegen/QrCode.hpp @@ -0,0 +1,556 @@ +/* + * QR Code generator library (C++) + * + * Copyright (c) Project Nayuki. (MIT License) + * https://www.nayuki.io/page/qr-code-generator-library + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of + * this software and associated documentation files (the "Software"), to deal in + * the Software without restriction, including without limitation the rights to + * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of + * the Software, and to permit persons to whom the Software is furnished to do so, + * subject to the following conditions: + * - The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * - The Software is provided "as is", without warranty of any kind, express or + * implied, including but not limited to the warranties of merchantability, + * fitness for a particular purpose and noninfringement. In no event shall the + * authors or copyright holders be liable for any claim, damages or other + * liability, whether in an action of contract, tort or otherwise, arising from, + * out of or in connection with the Software or the use or other dealings in the + * Software. + */ + +#pragma once + +#include <array> +#include <cstdint> +#include <stdexcept> +#include <string> +#include <vector> + + +namespace qrcodegen { + +/* + * A segment of character/binary/control data in a QR Code symbol. + * Instances of this class are immutable. + * The mid-level way to create a segment is to take the payload data + * and call a static factory function such as QrSegment::makeNumeric(). + * The low-level way to create a segment is to custom-make the bit buffer + * and call the QrSegment() constructor with appropriate values. + * This segment class imposes no length restrictions, but QR Codes have restrictions. + * Even in the most favorable conditions, a QR Code can only hold 7089 characters of data. + * Any segment longer than this is meaningless for the purpose of generating QR Codes. + */ +class QrSegment final { + + /*---- Public helper enumeration ----*/ + + /* + * Describes how a segment's data bits are interpreted. Immutable. + */ + public: class Mode final { + + /*-- Constants --*/ + + public: static const Mode NUMERIC; + public: static const Mode ALPHANUMERIC; + public: static const Mode BYTE; + public: static const Mode KANJI; + public: static const Mode ECI; + + + /*-- Fields --*/ + + // The mode indicator bits, which is a uint4 value (range 0 to 15). + private: int modeBits; + + // Number of character count bits for three different version ranges. + private: int numBitsCharCount[3]; + + + /*-- Constructor --*/ + + private: Mode(int mode, int cc0, int cc1, int cc2); + + + /*-- Methods --*/ + + /* + * (Package-private) Returns the mode indicator bits, which is an unsigned 4-bit value (range 0 to 15). + */ + public: int getModeBits() const; + + /* + * (Package-private) Returns the bit width of the character count field for a segment in + * this mode in a QR Code at the given version number. The result is in the range [0, 16]. + */ + public: int numCharCountBits(int ver) const; + + }; + + + + /*---- Static factory functions (mid level) ----*/ + + /* + * Returns a segment representing the given binary data encoded in + * byte mode. All input byte vectors are acceptable. Any text string + * can be converted to UTF-8 bytes and encoded as a byte mode segment. + */ + public: static QrSegment makeBytes(const std::vector<std::uint8_t> &data); + + + /* + * Returns a segment representing the given string of decimal digits encoded in numeric mode. + */ + public: static QrSegment makeNumeric(const char *digits); + + + /* + * Returns a segment representing the given text string encoded in alphanumeric mode. + * The characters allowed are: 0 to 9, A to Z (uppercase only), space, + * dollar, percent, asterisk, plus, hyphen, period, slash, colon. + */ + public: static QrSegment makeAlphanumeric(const char *text); + + + /* + * Returns a list of zero or more segments to represent the given text string. The result + * may use various segment modes and switch modes to optimize the length of the bit stream. + */ + public: static std::vector<QrSegment> makeSegments(const char *text); + + + /* + * Returns a segment representing an Extended Channel Interpretation + * (ECI) designator with the given assignment value. + */ + public: static QrSegment makeEci(long assignVal); + + + /*---- Public static helper functions ----*/ + + /* + * Tests whether the given string can be encoded as a segment in alphanumeric mode. + * A string is encodable iff each character is in the following set: 0 to 9, A to Z + * (uppercase only), space, dollar, percent, asterisk, plus, hyphen, period, slash, colon. + */ + public: static bool isAlphanumeric(const char *text); + + + /* + * Tests whether the given string can be encoded as a segment in numeric mode. + * A string is encodable iff each character is in the range 0 to 9. + */ + public: static bool isNumeric(const char *text); + + + + /*---- Instance fields ----*/ + + /* The mode indicator of this segment. Accessed through getMode(). */ + private: Mode mode; + + /* The length of this segment's unencoded data. Measured in characters for + * numeric/alphanumeric/kanji mode, bytes for byte mode, and 0 for ECI mode. + * Always zero or positive. Not the same as the data's bit length. + * Accessed through getNumChars(). */ + private: int numChars; + + /* The data bits of this segment. Accessed through getData(). */ + private: std::vector<bool> data; + + + /*---- Constructors (low level) ----*/ + + /* + * Creates a new QR Code segment with the given attributes and data. + * The character count (numCh) must agree with the mode and the bit buffer length, + * but the constraint isn't checked. The given bit buffer is copied and stored. + */ + public: QrSegment(Mode md, int numCh, const std::vector<bool> &dt); + + + /* + * Creates a new QR Code segment with the given parameters and data. + * The character count (numCh) must agree with the mode and the bit buffer length, + * but the constraint isn't checked. The given bit buffer is moved and stored. + */ + public: QrSegment(Mode md, int numCh, std::vector<bool> &&dt); + + + /*---- Methods ----*/ + + /* + * Returns the mode field of this segment. + */ + public: Mode getMode() const; + + + /* + * Returns the character count field of this segment. + */ + public: int getNumChars() const; + + + /* + * Returns the data bits of this segment. + */ + public: const std::vector<bool> &getData() const; + + + // (Package-private) Calculates the number of bits needed to encode the given segments at + // the given version. Returns a non-negative number if successful. Otherwise returns -1 if a + // segment has too many characters to fit its length field, or the total bits exceeds INT_MAX. + public: static int getTotalBits(const std::vector<QrSegment> &segs, int version); + + + /*---- Private constant ----*/ + + /* The set of all legal characters in alphanumeric mode, where + * each character value maps to the index in the string. */ + private: static const char *ALPHANUMERIC_CHARSET; + +}; + + + +/* + * A QR Code symbol, which is a type of two-dimension barcode. + * Invented by Denso Wave and described in the ISO/IEC 18004 standard. + * Instances of this class represent an immutable square grid of black and white cells. + * The class provides static factory functions to create a QR Code from text or binary data. + * The class covers the QR Code Model 2 specification, supporting all versions (sizes) + * from 1 to 40, all 4 error correction levels, and 4 character encoding modes. + * + * Ways to create a QR Code object: + * - High level: Take the payload data and call QrCode::encodeText() or QrCode::encodeBinary(). + * - Mid level: Custom-make the list of segments and call QrCode::encodeSegments(). + * - Low level: Custom-make the array of data codeword bytes (including + * segment headers and final padding, excluding error correction codewords), + * supply the appropriate version number, and call the QrCode() constructor. + * (Note that all ways require supplying the desired error correction level.) + */ +class QrCode final { + + /*---- Public helper enumeration ----*/ + + /* + * The error correction level in a QR Code symbol. + */ + public: enum class Ecc { + LOW = 0 , // The QR Code can tolerate about 7% erroneous codewords + MEDIUM , // The QR Code can tolerate about 15% erroneous codewords + QUARTILE, // The QR Code can tolerate about 25% erroneous codewords + HIGH , // The QR Code can tolerate about 30% erroneous codewords + }; + + + // Returns a value in the range 0 to 3 (unsigned 2-bit integer). + private: static int getFormatBits(Ecc ecl); + + + + /*---- Static factory functions (high level) ----*/ + + /* + * Returns a QR Code representing the given Unicode text string at the given error correction level. + * As a conservative upper bound, this function is guaranteed to succeed for strings that have 2953 or fewer + * UTF-8 code units (not Unicode code points) if the low error correction level is used. The smallest possible + * QR Code version is automatically chosen for the output. The ECC level of the result may be higher than + * the ecl argument if it can be done without increasing the version. + */ + public: static QrCode encodeText(const char *text, Ecc ecl); + + + /* + * Returns a QR Code representing the given binary data at the given error correction level. + * This function always encodes using the binary segment mode, not any text mode. The maximum number of + * bytes allowed is 2953. The smallest possible QR Code version is automatically chosen for the output. + * The ECC level of the result may be higher than the ecl argument if it can be done without increasing the version. + */ + public: static QrCode encodeBinary(const std::vector<std::uint8_t> &data, Ecc ecl); + + + /*---- Static factory functions (mid level) ----*/ + + /* + * Returns a QR Code representing the given segments with the given encoding parameters. + * The smallest possible QR Code version within the given range is automatically + * chosen for the output. Iff boostEcl is true, then the ECC level of the result + * may be higher than the ecl argument if it can be done without increasing the + * version. The mask number is either between 0 to 7 (inclusive) to force that + * mask, or -1 to automatically choose an appropriate mask (which may be slow). + * This function allows the user to create a custom sequence of segments that switches + * between modes (such as alphanumeric and byte) to encode text in less space. + * This is a mid-level API; the high-level API is encodeText() and encodeBinary(). + */ + public: static QrCode encodeSegments(const std::vector<QrSegment> &segs, Ecc ecl, + int minVersion=1, int maxVersion=40, int mask=-1, bool boostEcl=true); // All optional parameters + + + + /*---- Instance fields ----*/ + + // Immutable scalar parameters: + + /* The version number of this QR Code, which is between 1 and 40 (inclusive). + * This determines the size of this barcode. */ + private: int version; + + /* The width and height of this QR Code, measured in modules, between + * 21 and 177 (inclusive). This is equal to version * 4 + 17. */ + private: int size; + + /* The error correction level used in this QR Code. */ + private: Ecc errorCorrectionLevel; + + /* The index of the mask pattern used in this QR Code, which is between 0 and 7 (inclusive). + * Even if a QR Code is created with automatic masking requested (mask = -1), + * the resulting object still has a mask value between 0 and 7. */ + private: int mask; + + // Private grids of modules/pixels, with dimensions of size*size: + + // The modules of this QR Code (false = white, true = black). + // Immutable after constructor finishes. Accessed through getModule(). + private: std::vector<std::vector<bool> > modules; + + // Indicates function modules that are not subjected to masking. Discarded when constructor finishes. + private: std::vector<std::vector<bool> > isFunction; + + + + /*---- Constructor (low level) ----*/ + + /* + * Creates a new QR Code with the given version number, + * error correction level, data codeword bytes, and mask number. + * This is a low-level API that most users should not use directly. + * A mid-level API is the encodeSegments() function. + */ + public: QrCode(int ver, Ecc ecl, const std::vector<std::uint8_t> &dataCodewords, int msk); + + + + /*---- Public instance methods ----*/ + + /* + * Returns this QR Code's version, in the range [1, 40]. + */ + public: int getVersion() const; + + + /* + * Returns this QR Code's size, in the range [21, 177]. + */ + public: int getSize() const; + + + /* + * Returns this QR Code's error correction level. + */ + public: Ecc getErrorCorrectionLevel() const; + + + /* + * Returns this QR Code's mask, in the range [0, 7]. + */ + public: int getMask() const; + + + /* + * Returns the color of the module (pixel) at the given coordinates, which is false + * for white or true for black. The top left corner has the coordinates (x=0, y=0). + * If the given coordinates are out of bounds, then false (white) is returned. + */ + public: bool getModule(int x, int y) const; + + + /* + * Returns a string of SVG code for an image depicting this QR Code, with the given number + * of border modules. The string always uses Unix newlines (\n), regardless of the platform. + */ + public: std::string toSvgString(int border) const; + + + + /*---- Private helper methods for constructor: Drawing function modules ----*/ + + // Reads this object's version field, and draws and marks all function modules. + private: void drawFunctionPatterns(); + + + // Draws two copies of the format bits (with its own error correction code) + // based on the given mask and this object's error correction level field. + private: void drawFormatBits(int msk); + + + // Draws two copies of the version bits (with its own error correction code), + // based on this object's version field, iff 7 <= version <= 40. + private: void drawVersion(); + + + // Draws a 9*9 finder pattern including the border separator, + // with the center module at (x, y). Modules can be out of bounds. + private: void drawFinderPattern(int x, int y); + + + // Draws a 5*5 alignment pattern, with the center module + // at (x, y). All modules must be in bounds. + private: void drawAlignmentPattern(int x, int y); + + + // Sets the color of a module and marks it as a function module. + // Only used by the constructor. Coordinates must be in bounds. + private: void setFunctionModule(int x, int y, bool isBlack); + + + // Returns the color of the module at the given coordinates, which must be in range. + private: bool module(int x, int y) const; + + + /*---- Private helper methods for constructor: Codewords and masking ----*/ + + // Returns a new byte string representing the given data with the appropriate error correction + // codewords appended to it, based on this object's version and error correction level. + private: std::vector<std::uint8_t> addEccAndInterleave(const std::vector<std::uint8_t> &data) const; + + + // Draws the given sequence of 8-bit codewords (data and error correction) onto the entire + // data area of this QR Code. Function modules need to be marked off before this is called. + private: void drawCodewords(const std::vector<std::uint8_t> &data); + + + // XORs the codeword modules in this QR Code with the given mask pattern. + // The function modules must be marked and the codeword bits must be drawn + // before masking. Due to the arithmetic of XOR, calling applyMask() with + // the same mask value a second time will undo the mask. A final well-formed + // QR Code needs exactly one (not zero, two, etc.) mask applied. + private: void applyMask(int msk); + + + // Calculates and returns the penalty score based on state of this QR Code's current modules. + // This is used by the automatic mask choice algorithm to find the mask pattern that yields the lowest score. + private: long getPenaltyScore() const; + + + + /*---- Private helper functions ----*/ + + // Returns an ascending list of positions of alignment patterns for this version number. + // Each position is in the range [0,177), and are used on both the x and y axes. + // This could be implemented as lookup table of 40 variable-length lists of unsigned bytes. + private: std::vector<int> getAlignmentPatternPositions() const; + + + // Returns the number of data bits that can be stored in a QR Code of the given version number, after + // all function modules are excluded. This includes remainder bits, so it might not be a multiple of 8. + // The result is in the range [208, 29648]. This could be implemented as a 40-entry lookup table. + private: static int getNumRawDataModules(int ver); + + + // Returns the number of 8-bit data (i.e. not error correction) codewords contained in any + // QR Code of the given version number and error correction level, with remainder bits discarded. + // This stateless pure function could be implemented as a (40*4)-cell lookup table. + private: static int getNumDataCodewords(int ver, Ecc ecl); + + + // Returns a Reed-Solomon ECC generator polynomial for the given degree. This could be + // implemented as a lookup table over all possible parameter values, instead of as an algorithm. + private: static std::vector<std::uint8_t> reedSolomonComputeDivisor(int degree); + + + // Returns the Reed-Solomon error correction codeword for the given data and divisor polynomials. + private: static std::vector<std::uint8_t> reedSolomonComputeRemainder(const std::vector<std::uint8_t> &data, const std::vector<std::uint8_t> &divisor); + + + // Returns the product of the two given field elements modulo GF(2^8/0x11D). + // All inputs are valid. This could be implemented as a 256*256 lookup table. + private: static std::uint8_t reedSolomonMultiply(std::uint8_t x, std::uint8_t y); + + + // Can only be called immediately after a white run is added, and + // returns either 0, 1, or 2. A helper function for getPenaltyScore(). + private: int finderPenaltyCountPatterns(const std::array<int,7> &runHistory) const; + + + // Must be called at the end of a line (row or column) of modules. A helper function for getPenaltyScore(). + private: int finderPenaltyTerminateAndCount(bool currentRunColor, int currentRunLength, std::array<int,7> &runHistory) const; + + + // Pushes the given value to the front and drops the last value. A helper function for getPenaltyScore(). + private: void finderPenaltyAddHistory(int currentRunLength, std::array<int,7> &runHistory) const; + + + // Returns true iff the i'th bit of x is set to 1. + private: static bool getBit(long x, int i); + + + /*---- Constants and tables ----*/ + + // The minimum version number supported in the QR Code Model 2 standard. + public: static constexpr int MIN_VERSION = 1; + + // The maximum version number supported in the QR Code Model 2 standard. + public: static constexpr int MAX_VERSION = 40; + + + // For use in getPenaltyScore(), when evaluating which mask is best. + private: static const int PENALTY_N1; + private: static const int PENALTY_N2; + private: static const int PENALTY_N3; + private: static const int PENALTY_N4; + + + private: static const std::int8_t ECC_CODEWORDS_PER_BLOCK[4][41]; + private: static const std::int8_t NUM_ERROR_CORRECTION_BLOCKS[4][41]; + +}; + + + +/*---- Public exception class ----*/ + +/* + * Thrown when the supplied data does not fit any QR Code version. Ways to handle this exception include: + * - Decrease the error correction level if it was greater than Ecc::LOW. + * - If the encodeSegments() function was called with a maxVersion argument, then increase + * it if it was less than QrCode::MAX_VERSION. (This advice does not apply to the other + * factory functions because they search all versions up to QrCode::MAX_VERSION.) + * - Split the text data into better or optimal segments in order to reduce the number of bits required. + * - Change the text or binary data to be shorter. + * - Change the text to fit the character set of a particular segment mode (e.g. alphanumeric). + * - Propagate the error upward to the caller/user. + */ +class data_too_long : public std::length_error { + + public: explicit data_too_long(const std::string &msg); + +}; + + + +/* + * An appendable sequence of bits (0s and 1s). Mainly used by QrSegment. + */ +class BitBuffer final : public std::vector<bool> { + + /*---- Constructor ----*/ + + // Creates an empty bit buffer (length 0). + public: BitBuffer(); + + + + /*---- Method ----*/ + + // Appends the given number of low-order bits of the given value + // to this buffer. Requires 0 <= len <= 31 and val < 2^len. + public: void appendBits(std::uint32_t val, int len); + +}; + +} |