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Diffstat (limited to 'clients/common/qrcodegen.c')
| -rw-r--r-- | clients/common/qrcodegen.c | 1141 |
1 files changed, 0 insertions, 1141 deletions
diff --git a/clients/common/qrcodegen.c b/clients/common/qrcodegen.c deleted file mode 100644 index 2c40fcb9..00000000 --- a/clients/common/qrcodegen.c +++ /dev/null @@ -1,1141 +0,0 @@ -/* - * 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 <assert.h> -#include <limits.h> -#include <stdlib.h> -#include <string.h> -#include "qrcodegen.h" - -#ifndef QRCODEGEN_TEST - #define testable static // Keep functions private -#else - #define testable // Expose private functions -#endif - -/*---- Forward declarations for private functions ----*/ - -// Regarding all public and private functions defined in this source file: -// - They require all pointer/array arguments to be not null unless the array length is zero. -// - They only read input scalar/array arguments, write to output pointer/array -// arguments, and return scalar values; they are "pure" functions. -// - They don't read mutable global variables or write to any global variables. -// - They don't perform I/O, read the clock, print to console, etc. -// - They allocate a small and constant amount of stack memory. -// - They don't allocate or free any memory on the heap. -// - They don't recurse or mutually recurse. All the code -// could be inlined into the top-level public functions. -// - They run in at most quadratic time with respect to input arguments. -// Most functions run in linear time, and some in constant time. -// There are no unbounded loops or non-obvious termination conditions. -// - They are completely thread-safe if the caller does not give the -// same writable buffer to concurrent calls to these functions. - -testable void appendBitsToBuffer(unsigned int val, int numBits, uint8_t buffer[], int *bitLen); - -testable void -addEccAndInterleave(uint8_t data[], int version, enum qrcodegen_Ecc ecl, uint8_t result[]); -testable int getNumDataCodewords(int version, enum qrcodegen_Ecc ecl); -testable int getNumRawDataModules(int ver); - -testable void calcReedSolomonGenerator(int degree, uint8_t result[]); -testable void calcReedSolomonRemainder(const uint8_t data[], - int dataLen, - const uint8_t generator[], - int degree, - uint8_t result[]); -testable uint8_t finiteFieldMultiply(uint8_t x, uint8_t y); - -testable void initializeFunctionModules(int version, uint8_t qrcode[]); -static void drawWhiteFunctionModules(uint8_t qrcode[], int version); -static void drawFormatBits(enum qrcodegen_Ecc ecl, enum qrcodegen_Mask mask, uint8_t qrcode[]); -testable int getAlignmentPatternPositions(int version, uint8_t result[7]); -static void fillRectangle(int left, int top, int width, int height, uint8_t qrcode[]); - -static void drawCodewords(const uint8_t data[], int dataLen, uint8_t qrcode[]); -static void applyMask(const uint8_t functionModules[], uint8_t qrcode[], enum qrcodegen_Mask mask); -static long getPenaltyScore(const uint8_t qrcode[]); -static void addRunToHistory(unsigned char run, unsigned char history[7]); -static bool hasFinderLikePattern(unsigned char runHistory[7]); - -testable bool getModule(const uint8_t qrcode[], int x, int y); -testable void setModule(uint8_t qrcode[], int x, int y, bool isBlack); -testable void setModuleBounded(uint8_t qrcode[], int x, int y, bool isBlack); -static bool getBit(int x, int i); - -testable int calcSegmentBitLength(enum qrcodegen_Mode mode, size_t numChars); -testable int getTotalBits(const struct qrcodegen_Segment segs[], size_t len, int version); -static int numCharCountBits(enum qrcodegen_Mode mode, int version); - -/*---- Private tables of constants ----*/ - -// The set of all legal characters in alphanumeric mode, where each character -// value maps to the index in the string. For checking text and encoding segments. -static const char *ALPHANUMERIC_CHARSET = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ $%*+-./:"; - -// For generating error correction codes. -testable const int8_t 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 -}; - -#define qrcodegen_REED_SOLOMON_DEGREE_MAX 30 // Based on the table above - -// For generating error correction codes. -testable const int8_t 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 -}; - -// For automatic mask pattern selection. -static const int PENALTY_N1 = 3; -static const int PENALTY_N2 = 3; -static const int PENALTY_N3 = 40; -static const int PENALTY_N4 = 10; - -/*---- High-level QR Code encoding functions ----*/ - -// Public function - see documentation comment in header file. -bool -qrcodegen_encodeText(const char * text, - uint8_t tempBuffer[], - uint8_t qrcode[], - enum qrcodegen_Ecc ecl, - int minVersion, - int maxVersion, - enum qrcodegen_Mask mask, - bool boostEcl) -{ - size_t textLen = strlen(text); - if (textLen == 0) - return qrcodegen_encodeSegmentsAdvanced(NULL, - 0, - ecl, - minVersion, - maxVersion, - mask, - boostEcl, - tempBuffer, - qrcode); - size_t bufLen = qrcodegen_BUFFER_LEN_FOR_VERSION(maxVersion); - - struct qrcodegen_Segment seg; - if (qrcodegen_isNumeric(text)) { - if (qrcodegen_calcSegmentBufferSize(qrcodegen_Mode_NUMERIC, textLen) > bufLen) - goto fail; - seg = qrcodegen_makeNumeric(text, tempBuffer); - } else if (qrcodegen_isAlphanumeric(text)) { - if (qrcodegen_calcSegmentBufferSize(qrcodegen_Mode_ALPHANUMERIC, textLen) > bufLen) - goto fail; - seg = qrcodegen_makeAlphanumeric(text, tempBuffer); - } else { - if (textLen > bufLen) - goto fail; - for (size_t i = 0; i < textLen; i++) - tempBuffer[i] = (uint8_t) text[i]; - seg.mode = qrcodegen_Mode_BYTE; - seg.bitLength = calcSegmentBitLength(seg.mode, textLen); - if (seg.bitLength == -1) - goto fail; - seg.numChars = (int) textLen; - seg.data = tempBuffer; - } - return qrcodegen_encodeSegmentsAdvanced(&seg, - 1, - ecl, - minVersion, - maxVersion, - mask, - boostEcl, - tempBuffer, - qrcode); - -fail: - qrcode[0] = 0; // Set size to invalid value for safety - return false; -} - -// Public function - see documentation comment in header file. -bool -qrcodegen_encodeBinary(uint8_t dataAndTemp[], - size_t dataLen, - uint8_t qrcode[], - enum qrcodegen_Ecc ecl, - int minVersion, - int maxVersion, - enum qrcodegen_Mask mask, - bool boostEcl) -{ - struct qrcodegen_Segment seg; - seg.mode = qrcodegen_Mode_BYTE; - seg.bitLength = calcSegmentBitLength(seg.mode, dataLen); - if (seg.bitLength == -1) { - qrcode[0] = 0; // Set size to invalid value for safety - return false; - } - seg.numChars = (int) dataLen; - seg.data = dataAndTemp; - return qrcodegen_encodeSegmentsAdvanced(&seg, - 1, - ecl, - minVersion, - maxVersion, - mask, - boostEcl, - dataAndTemp, - qrcode); -} - -// Appends the given number of low-order bits of the given value to the given byte-based -// bit buffer, increasing the bit length. Requires 0 <= numBits <= 16 and val < 2^numBits. -testable void -appendBitsToBuffer(unsigned int val, int numBits, uint8_t buffer[], int *bitLen) -{ - assert(0 <= numBits && numBits <= 16 && (unsigned long) val >> numBits == 0); - for (int i = numBits - 1; i >= 0; i--, (*bitLen)++) - buffer[*bitLen >> 3] |= ((val >> i) & 1) << (7 - (*bitLen & 7)); -} - -/*---- Low-level QR Code encoding functions ----*/ - -// Public function - see documentation comment in header file. -bool -qrcodegen_encodeSegments(const struct qrcodegen_Segment segs[], - size_t len, - enum qrcodegen_Ecc ecl, - uint8_t tempBuffer[], - uint8_t qrcode[]) -{ - return qrcodegen_encodeSegmentsAdvanced(segs, - len, - ecl, - qrcodegen_VERSION_MIN, - qrcodegen_VERSION_MAX, - -1, - true, - tempBuffer, - qrcode); -} - -// Public function - see documentation comment in header file. -bool -qrcodegen_encodeSegmentsAdvanced(const struct qrcodegen_Segment segs[], - size_t len, - enum qrcodegen_Ecc ecl, - int minVersion, - int maxVersion, - int mask, - bool boostEcl, - uint8_t tempBuffer[], - uint8_t qrcode[]) -{ - assert(segs != NULL || len == 0); - assert(qrcodegen_VERSION_MIN <= minVersion && minVersion <= maxVersion - && maxVersion <= qrcodegen_VERSION_MAX); - assert(0 <= (int) ecl && (int) ecl <= 3 && -1 <= (int) mask && (int) mask <= 7); - - // 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 = getTotalBits(segs, len, 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 - qrcode[0] = 0; // Set size to invalid value for safety - return false; - } - } - assert(dataUsedBits != -1); - - // Increase the error correction level while the data still fits in the current version number - for (int i = (int) qrcodegen_Ecc_MEDIUM; i <= (int) qrcodegen_Ecc_HIGH; - i++) { // From low to high - if (boostEcl && dataUsedBits <= getNumDataCodewords(version, (enum qrcodegen_Ecc) i) * 8) - ecl = (enum qrcodegen_Ecc) i; - } - - // Concatenate all segments to create the data bit string - memset(qrcode, 0, qrcodegen_BUFFER_LEN_FOR_VERSION(version) * sizeof(qrcode[0])); - int bitLen = 0; - for (size_t i = 0; i < len; i++) { - const struct qrcodegen_Segment *seg = &segs[i]; - appendBitsToBuffer((int) seg->mode, 4, qrcode, &bitLen); - appendBitsToBuffer(seg->numChars, numCharCountBits(seg->mode, version), qrcode, &bitLen); - for (int j = 0; j < seg->bitLength; j++) - appendBitsToBuffer((seg->data[j >> 3] >> (7 - (j & 7))) & 1, 1, qrcode, &bitLen); - } - assert(bitLen == dataUsedBits); - - // Add terminator and pad up to a byte if applicable - int dataCapacityBits = getNumDataCodewords(version, ecl) * 8; - assert(bitLen <= dataCapacityBits); - int terminatorBits = dataCapacityBits - bitLen; - if (terminatorBits > 4) - terminatorBits = 4; - appendBitsToBuffer(0, terminatorBits, qrcode, &bitLen); - appendBitsToBuffer(0, (8 - bitLen % 8) % 8, qrcode, &bitLen); - assert(bitLen % 8 == 0); - - // Pad with alternating bytes until data capacity is reached - for (uint8_t padByte = 0xEC; bitLen < dataCapacityBits; padByte ^= 0xEC ^ 0x11) - appendBitsToBuffer(padByte, 8, qrcode, &bitLen); - - // Draw function and data codeword modules - addEccAndInterleave(qrcode, version, ecl, tempBuffer); - initializeFunctionModules(version, qrcode); - drawCodewords(tempBuffer, getNumRawDataModules(version) / 8, qrcode); - drawWhiteFunctionModules(qrcode, version); - initializeFunctionModules(version, tempBuffer); - - // Handle masking - if (mask == qrcodegen_Mask_AUTO) { // Automatically choose best mask - long minPenalty = LONG_MAX; - for (int i = 0; i < 8; i++) { - enum qrcodegen_Mask msk = (enum qrcodegen_Mask) i; - drawFormatBits(ecl, msk, qrcode); - applyMask(tempBuffer, qrcode, msk); - long penalty = getPenaltyScore(qrcode); - if (penalty < minPenalty) { - mask = msk; - minPenalty = penalty; - } - applyMask(tempBuffer, qrcode, msk); // Undoes the mask due to XOR - } - } - assert(0 <= (int) mask && (int) mask <= 7); - drawFormatBits(ecl, mask, qrcode); - applyMask(tempBuffer, qrcode, mask); - return true; -} - -/*---- Error correction code generation functions ----*/ - -// Appends error correction bytes to each block of the given data array, then interleaves -// bytes from the blocks and stores them in the result array. data[0 : dataLen] contains -// the input data. data[dataLen : rawCodewords] is used as a temporary work area and will -// be clobbered by this function. The final answer is stored in result[0 : rawCodewords]. -testable void -addEccAndInterleave(uint8_t data[], int version, enum qrcodegen_Ecc ecl, uint8_t result[]) -{ - // Calculate parameter numbers - assert(0 <= (int) ecl && (int) ecl < 4 && qrcodegen_VERSION_MIN <= version - && version <= qrcodegen_VERSION_MAX); - int numBlocks = NUM_ERROR_CORRECTION_BLOCKS[(int) ecl][version]; - int blockEccLen = ECC_CODEWORDS_PER_BLOCK[(int) ecl][version]; - int rawCodewords = getNumRawDataModules(version) / 8; - int dataLen = getNumDataCodewords(version, ecl); - int numShortBlocks = numBlocks - rawCodewords % numBlocks; - int shortBlockDataLen = rawCodewords / numBlocks - blockEccLen; - - // Split data into blocks, calculate ECC, and interleave - // (not concatenate) the bytes into a single sequence - uint8_t generator[qrcodegen_REED_SOLOMON_DEGREE_MAX]; - calcReedSolomonGenerator(blockEccLen, generator); - const uint8_t *dat = data; - for (int i = 0; i < numBlocks; i++) { - int datLen = shortBlockDataLen + (i < numShortBlocks ? 0 : 1); - uint8_t *ecc = &data[dataLen]; // Temporary storage - calcReedSolomonRemainder(dat, datLen, generator, blockEccLen, ecc); - for (int j = 0, k = i; j < datLen; j++, k += numBlocks) { // Copy data - if (j == shortBlockDataLen) - k -= numShortBlocks; - result[k] = dat[j]; - } - for (int j = 0, k = dataLen + i; j < blockEccLen; j++, k += numBlocks) // Copy ECC - result[k] = ecc[j]; - dat += datLen; - } -} - -// Returns the number of 8-bit codewords that can be used for storing data (not ECC), -// for the given version number and error correction level. The result is in the range [9, 2956]. -testable int -getNumDataCodewords(int version, enum qrcodegen_Ecc ecl) -{ - int v = version, e = (int) ecl; - assert(0 <= e && e < 4); - return getNumRawDataModules(v) / 8 - - ECC_CODEWORDS_PER_BLOCK[e][v] * NUM_ERROR_CORRECTION_BLOCKS[e][v]; -} - -// 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. -testable int -getNumRawDataModules(int ver) -{ - assert(qrcodegen_VERSION_MIN <= ver && ver <= qrcodegen_VERSION_MAX); - 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; - } - return result; -} - -/*---- Reed-Solomon ECC generator functions ----*/ - -// Calculates the Reed-Solomon generator polynomial of the given degree, storing in result[0 : degree]. -testable void -calcReedSolomonGenerator(int degree, uint8_t result[]) -{ - // Start with the monomial x^0 - assert(1 <= degree && degree <= qrcodegen_REED_SOLOMON_DEGREE_MAX); - memset(result, 0, degree * sizeof(result[0])); - result[degree - 1] = 1; - - // Compute the product polynomial (x - r^0) * (x - r^1) * (x - r^2) * ... * (x - r^{degree-1}), - // drop the highest term, and store the rest of the coefficients in order of descending powers. - // 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 (int j = 0; j < degree; j++) { - result[j] = finiteFieldMultiply(result[j], root); - if (j + 1 < degree) - result[j] ^= result[j + 1]; - } - root = finiteFieldMultiply(root, 0x02); - } -} - -// Calculates the remainder of the polynomial data[0 : dataLen] when divided by the generator[0 : degree], where all -// polynomials are in big endian and the generator has an implicit leading 1 term, storing the result in result[0 : degree]. -testable void -calcReedSolomonRemainder(const uint8_t data[], - int dataLen, - const uint8_t generator[], - int degree, - uint8_t result[]) -{ - // Perform polynomial division - assert(1 <= degree && degree <= qrcodegen_REED_SOLOMON_DEGREE_MAX); - memset(result, 0, degree * sizeof(result[0])); - for (int i = 0; i < dataLen; i++) { - uint8_t factor = data[i] ^ result[0]; - memmove(&result[0], &result[1], (degree - 1) * sizeof(result[0])); - result[degree - 1] = 0; - for (int j = 0; j < degree; j++) - result[j] ^= finiteFieldMultiply(generator[j], factor); - } -} - -#undef qrcodegen_REED_SOLOMON_DEGREE_MAX - -// 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. -testable uint8_t -finiteFieldMultiply(uint8_t x, uint8_t y) -{ - // Russian peasant multiplication - uint8_t z = 0; - for (int i = 7; i >= 0; i--) { - z = (z << 1) ^ ((z >> 7) * 0x11D); - z ^= ((y >> i) & 1) * x; - } - return z; -} - -/*---- Drawing function modules ----*/ - -// Clears the given QR Code grid with white modules for the given -// version's size, then marks every function module as black. -testable void -initializeFunctionModules(int version, uint8_t qrcode[]) -{ - // Initialize QR Code - int qrsize = version * 4 + 17; - memset(qrcode, 0, ((qrsize * qrsize + 7) / 8 + 1) * sizeof(qrcode[0])); - qrcode[0] = (uint8_t) qrsize; - - // Fill horizontal and vertical timing patterns - fillRectangle(6, 0, 1, qrsize, qrcode); - fillRectangle(0, 6, qrsize, 1, qrcode); - - // Fill 3 finder patterns (all corners except bottom right) and format bits - fillRectangle(0, 0, 9, 9, qrcode); - fillRectangle(qrsize - 8, 0, 8, 9, qrcode); - fillRectangle(0, qrsize - 8, 9, 8, qrcode); - - // Fill numerous alignment patterns - uint8_t alignPatPos[7]; - int numAlign = getAlignmentPatternPositions(version, alignPatPos); - for (int i = 0; i < numAlign; i++) { - for (int 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))) - fillRectangle(alignPatPos[i] - 2, alignPatPos[j] - 2, 5, 5, qrcode); - } - } - - // Fill version blocks - if (version >= 7) { - fillRectangle(qrsize - 11, 0, 3, 6, qrcode); - fillRectangle(0, qrsize - 11, 6, 3, qrcode); - } -} - -// Draws white function modules and possibly some black modules onto the given QR Code, without changing -// non-function modules. This does not draw the format bits. This requires all function modules to be previously -// marked black (namely by initializeFunctionModules()), because this may skip redrawing black function modules. -static void -drawWhiteFunctionModules(uint8_t qrcode[], int version) -{ - // Draw horizontal and vertical timing patterns - int qrsize = qrcodegen_getSize(qrcode); - for (int i = 7; i < qrsize - 7; i += 2) { - setModule(qrcode, 6, i, false); - setModule(qrcode, i, 6, false); - } - - // Draw 3 finder patterns (all corners except bottom right; overwrites some timing modules) - for (int dy = -4; dy <= 4; dy++) { - for (int dx = -4; dx <= 4; dx++) { - int dist = abs(dx); - if (abs(dy) > dist) - dist = abs(dy); - if (dist == 2 || dist == 4) { - setModuleBounded(qrcode, 3 + dx, 3 + dy, false); - setModuleBounded(qrcode, qrsize - 4 + dx, 3 + dy, false); - setModuleBounded(qrcode, 3 + dx, qrsize - 4 + dy, false); - } - } - } - - // Draw numerous alignment patterns - uint8_t alignPatPos[7]; - int numAlign = getAlignmentPatternPositions(version, alignPatPos); - for (int i = 0; i < numAlign; i++) { - for (int j = 0; j < numAlign; j++) { - if ((i == 0 && j == 0) || (i == 0 && j == numAlign - 1) - || (i == numAlign - 1 && j == 0)) - continue; // Don't draw on the three finder corners - for (int dy = -1; dy <= 1; dy++) { - for (int dx = -1; dx <= 1; dx++) - setModule(qrcode, alignPatPos[i] + dx, alignPatPos[j] + dy, dx == 0 && dy == 0); - } - } - } - - // Draw version blocks - if (version >= 7) { - // 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 = (long) version << 12 | rem; // uint18 - assert(bits >> 18 == 0); - - // Draw two copies - for (int i = 0; i < 6; i++) { - for (int j = 0; j < 3; j++) { - int k = qrsize - 11 + j; - setModule(qrcode, k, i, (bits & 1) != 0); - setModule(qrcode, i, k, (bits & 1) != 0); - bits >>= 1; - } - } - } -} - -// Draws two copies of the format bits (with its own error correction code) based -// on the given mask and error correction level. This always draws all modules of -// the format bits, unlike drawWhiteFunctionModules() which might skip black modules. -static void -drawFormatBits(enum qrcodegen_Ecc ecl, enum qrcodegen_Mask mask, uint8_t qrcode[]) -{ - // Calculate error correction code and pack bits - assert(0 <= (int) mask && (int) mask <= 7); - static const int table[] = {1, 0, 3, 2}; - int data = table[(int) ecl] << 3 | (int) mask; // errCorrLvl is uint2, mask 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 - assert(bits >> 15 == 0); - - // Draw first copy - for (int i = 0; i <= 5; i++) - setModule(qrcode, 8, i, getBit(bits, i)); - setModule(qrcode, 8, 7, getBit(bits, 6)); - setModule(qrcode, 8, 8, getBit(bits, 7)); - setModule(qrcode, 7, 8, getBit(bits, 8)); - for (int i = 9; i < 15; i++) - setModule(qrcode, 14 - i, 8, getBit(bits, i)); - - // Draw second copy - int qrsize = qrcodegen_getSize(qrcode); - for (int i = 0; i < 8; i++) - setModule(qrcode, qrsize - 1 - i, 8, getBit(bits, i)); - for (int i = 8; i < 15; i++) - setModule(qrcode, 8, qrsize - 15 + i, getBit(bits, i)); - setModule(qrcode, 8, qrsize - 8, true); // Always black -} - -// Calculates and stores an ascending list of positions of alignment patterns -// for this version number, returning the length of the list (in the range [0,7]). -// 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. -testable int -getAlignmentPatternPositions(int version, uint8_t result[7]) -{ - if (version == 1) - return 0; - int numAlign = version / 7 + 2; - int step = (version == 32) ? 26 : (version * 4 + numAlign * 2 + 1) / (numAlign * 2 - 2) * 2; - for (int i = numAlign - 1, pos = version * 4 + 10; i >= 1; i--, pos -= step) - result[i] = pos; - result[0] = 6; - return numAlign; -} - -// Sets every pixel in the range [left : left + width] * [top : top + height] to black. -static void -fillRectangle(int left, int top, int width, int height, uint8_t qrcode[]) -{ - for (int dy = 0; dy < height; dy++) { - for (int dx = 0; dx < width; dx++) - setModule(qrcode, left + dx, top + dy, true); - } -} - -/*---- Drawing data modules and masking ----*/ - -// Draws the raw codewords (including data and ECC) onto the given QR Code. This requires the initial state of -// the QR Code to be black at function modules and white at codeword modules (including unused remainder bits). -static void -drawCodewords(const uint8_t data[], int dataLen, uint8_t qrcode[]) -{ - int qrsize = qrcodegen_getSize(qrcode); - int i = 0; // Bit index into the data - // Do the funny zigzag scan - for (int right = qrsize - 1; right >= 1; - right -= 2) { // Index of right column in each column pair - if (right == 6) - right = 5; - for (int vert = 0; vert < qrsize; vert++) { // Vertical counter - for (int j = 0; j < 2; j++) { - int x = right - j; // Actual x coordinate - bool upward = ((right + 1) & 2) == 0; - int y = upward ? qrsize - 1 - vert : vert; // Actual y coordinate - if (!getModule(qrcode, x, y) && i < dataLen * 8) { - bool black = getBit(data[i >> 3], 7 - (i & 7)); - setModule(qrcode, x, y, black); - 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 - } - } - } - assert(i == dataLen * 8); -} - -// 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. -static void -applyMask(const uint8_t functionModules[], uint8_t qrcode[], enum qrcodegen_Mask mask) -{ - assert(0 <= (int) mask && (int) mask <= 7); // Disallows qrcodegen_Mask_AUTO - int qrsize = qrcodegen_getSize(qrcode); - for (int y = 0; y < qrsize; y++) { - for (int x = 0; x < qrsize; x++) { - if (getModule(functionModules, x, y)) - continue; - bool invert; - switch ((int) mask) { - 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: - assert(false); - return; - } - bool val = getModule(qrcode, x, y); - setModule(qrcode, x, y, val ^ invert); - } - } -} - -// Calculates and returns the penalty score based on state of the given QR Code's current modules. -// This is used by the automatic mask choice algorithm to find the mask pattern that yields the lowest score. -static long -getPenaltyScore(const uint8_t qrcode[]) -{ - int qrsize = qrcodegen_getSize(qrcode); - long result = 0; - - // Adjacent modules in row having same color, and finder-like patterns - for (int y = 0; y < qrsize; y++) { - unsigned char runHistory[7] = {0}; - bool color = false; - unsigned char runX = 0; - for (int x = 0; x < qrsize; x++) { - if (getModule(qrcode, x, y) == color) { - runX++; - if (runX == 5) - result += PENALTY_N1; - else if (runX > 5) - result++; - } else { - addRunToHistory(runX, runHistory); - if (!color && hasFinderLikePattern(runHistory)) - result += PENALTY_N3; - color = getModule(qrcode, x, y); - runX = 1; - } - } - addRunToHistory(runX, runHistory); - if (color) - addRunToHistory(0, runHistory); // Dummy run of white - if (hasFinderLikePattern(runHistory)) - result += PENALTY_N3; - } - // Adjacent modules in column having same color, and finder-like patterns - for (int x = 0; x < qrsize; x++) { - unsigned char runHistory[7] = {0}; - bool color = false; - unsigned char runY = 0; - for (int y = 0; y < qrsize; y++) { - if (getModule(qrcode, x, y) == color) { - runY++; - if (runY == 5) - result += PENALTY_N1; - else if (runY > 5) - result++; - } else { - addRunToHistory(runY, runHistory); - if (!color && hasFinderLikePattern(runHistory)) - result += PENALTY_N3; - color = getModule(qrcode, x, y); - runY = 1; - } - } - addRunToHistory(runY, runHistory); - if (color) - addRunToHistory(0, runHistory); // Dummy run of white - if (hasFinderLikePattern(runHistory)) - result += PENALTY_N3; - } - - // 2*2 blocks of modules having same color - for (int y = 0; y < qrsize - 1; y++) { - for (int x = 0; x < qrsize - 1; x++) { - bool color = getModule(qrcode, x, y); - if (color == getModule(qrcode, x + 1, y) && color == getModule(qrcode, x, y + 1) - && color == getModule(qrcode, x + 1, y + 1)) - result += PENALTY_N2; - } - } - - // Balance of black and white modules - int black = 0; - for (int y = 0; y < qrsize; y++) { - for (int x = 0; x < qrsize; x++) { - if (getModule(qrcode, x, y)) - black++; - } - } - int total = qrsize * qrsize; // 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 = (int) ((labs(black * 20L - total * 10L) + total - 1) / total) - 1; - result += k * PENALTY_N4; - return result; -} - -// Inserts the given value to the front of the given array, which shifts over the -// existing values and deletes the last value. A helper function for getPenaltyScore(). -static void -addRunToHistory(unsigned char run, unsigned char history[7]) -{ - memmove(&history[1], &history[0], 6 * sizeof(history[0])); - history[0] = run; -} - -// Tests whether the given run history has the pattern of ratio 1:1:3:1:1 in the middle, and -// surrounded by at least 4 on either or both ends. A helper function for getPenaltyScore(). -// Must only be called immediately after a run of white modules has ended. -static bool -hasFinderLikePattern(unsigned char runHistory[7]) -{ - unsigned char n = runHistory[1]; - // The maximum QR Code size is 177, hence the run length n <= 177. - // Arithmetic is promoted to int, so n*4 will not overflow. - return n > 0 && runHistory[2] == n && runHistory[4] == n && runHistory[5] == n - && runHistory[3] == n * 3 && (runHistory[0] >= n * 4 || runHistory[6] >= n * 4); -} - -/*---- Basic QR Code information ----*/ - -// Public function - see documentation comment in header file. -int -qrcodegen_getSize(const uint8_t qrcode[]) -{ - assert(qrcode != NULL); - int result = qrcode[0]; - assert((qrcodegen_VERSION_MIN * 4 + 17) <= result - && result <= (qrcodegen_VERSION_MAX * 4 + 17)); - return result; -} - -// Public function - see documentation comment in header file. -bool -qrcodegen_getModule(const uint8_t qrcode[], int x, int y) -{ - assert(qrcode != NULL); - int qrsize = qrcode[0]; - return (0 <= x && x < qrsize && 0 <= y && y < qrsize) && getModule(qrcode, x, y); -} - -// Gets the module at the given coordinates, which must be in bounds. -testable bool -getModule(const uint8_t qrcode[], int x, int y) -{ - int qrsize = qrcode[0]; - assert(21 <= qrsize && qrsize <= 177 && 0 <= x && x < qrsize && 0 <= y && y < qrsize); - int index = y * qrsize + x; - return getBit(qrcode[(index >> 3) + 1], index & 7); -} - -// Sets the module at the given coordinates, which must be in bounds. -testable void -setModule(uint8_t qrcode[], int x, int y, bool isBlack) -{ - int qrsize = qrcode[0]; - assert(21 <= qrsize && qrsize <= 177 && 0 <= x && x < qrsize && 0 <= y && y < qrsize); - int index = y * qrsize + x; - int bitIndex = index & 7; - int byteIndex = (index >> 3) + 1; - if (isBlack) - qrcode[byteIndex] |= 1 << bitIndex; - else - qrcode[byteIndex] &= (1 << bitIndex) ^ 0xFF; -} - -// Sets the module at the given coordinates, doing nothing if out of bounds. -testable void -setModuleBounded(uint8_t qrcode[], int x, int y, bool isBlack) -{ - int qrsize = qrcode[0]; - if (0 <= x && x < qrsize && 0 <= y && y < qrsize) - setModule(qrcode, x, y, isBlack); -} - -// Returns true iff the i'th bit of x is set to 1. Requires x >= 0 and 0 <= i <= 14. -static bool -getBit(int x, int i) -{ - return ((x >> i) & 1) != 0; -} - -/*---- Segment handling ----*/ - -// Public function - see documentation comment in header file. -bool -qrcodegen_isAlphanumeric(const char *text) -{ - assert(text != NULL); - for (; *text != '\0'; text++) { - if (strchr(ALPHANUMERIC_CHARSET, *text) == NULL) - return false; - } - return true; -} - -// Public function - see documentation comment in header file. -bool -qrcodegen_isNumeric(const char *text) -{ - assert(text != NULL); - for (; *text != '\0'; text++) { - if (*text < '0' || *text > '9') - return false; - } - return true; -} - -// Public function - see documentation comment in header file. -size_t -qrcodegen_calcSegmentBufferSize(enum qrcodegen_Mode mode, size_t numChars) -{ - int temp = calcSegmentBitLength(mode, numChars); - if (temp == -1) - return SIZE_MAX; - assert(0 <= temp && temp <= INT16_MAX); - return ((size_t) temp + 7) / 8; -} - -// Returns the number of data bits needed to represent a segment -// containing the given number of characters using the given mode. Notes: -// - Returns -1 on failure, i.e. numChars > INT16_MAX or -// the number of needed bits exceeds INT16_MAX (i.e. 32767). -// - Otherwise, all valid results are in the range [0, INT16_MAX]. -// - For byte mode, numChars measures the number of bytes, not Unicode code points. -// - For ECI mode, numChars must be 0, and the worst-case number of bits is returned. -// An actual ECI segment can have shorter data. For non-ECI modes, the result is exact. -testable int -calcSegmentBitLength(enum qrcodegen_Mode mode, size_t numChars) -{ - // All calculations are designed to avoid overflow on all platforms - if (numChars > (unsigned int) INT16_MAX) - return -1; - long result = (long) numChars; - if (mode == qrcodegen_Mode_NUMERIC) - result = (result * 10 + 2) / 3; // ceil(10/3 * n) - else if (mode == qrcodegen_Mode_ALPHANUMERIC) - result = (result * 11 + 1) / 2; // ceil(11/2 * n) - else if (mode == qrcodegen_Mode_BYTE) - result *= 8; - else if (mode == qrcodegen_Mode_KANJI) - result *= 13; - else if (mode == qrcodegen_Mode_ECI && numChars == 0) - result = 3 * 8; - else { // Invalid argument - assert(false); - return -1; - } - assert(result >= 0); - if (result > (unsigned int) INT16_MAX) - return -1; - return (int) result; -} - -// Public function - see documentation comment in header file. -struct qrcodegen_Segment -qrcodegen_makeBytes(const uint8_t data[], size_t len, uint8_t buf[]) -{ - assert(data != NULL || len == 0); - struct qrcodegen_Segment result; - result.mode = qrcodegen_Mode_BYTE; - result.bitLength = calcSegmentBitLength(result.mode, len); - assert(result.bitLength != -1); - result.numChars = (int) len; - if (len > 0) - memcpy(buf, data, len * sizeof(buf[0])); - result.data = buf; - return result; -} - -// Public function - see documentation comment in header file. -struct qrcodegen_Segment -qrcodegen_makeNumeric(const char *digits, uint8_t buf[]) -{ - assert(digits != NULL); - struct qrcodegen_Segment result; - size_t len = strlen(digits); - result.mode = qrcodegen_Mode_NUMERIC; - int bitLen = calcSegmentBitLength(result.mode, len); - assert(bitLen != -1); - result.numChars = (int) len; - if (bitLen > 0) - memset(buf, 0, ((size_t) bitLen + 7) / 8 * sizeof(buf[0])); - result.bitLength = 0; - - unsigned int accumData = 0; - int accumCount = 0; - for (; *digits != '\0'; digits++) { - char c = *digits; - assert('0' <= c && c <= '9'); - accumData = accumData * 10 + (unsigned int) (c - '0'); - accumCount++; - if (accumCount == 3) { - appendBitsToBuffer(accumData, 10, buf, &result.bitLength); - accumData = 0; - accumCount = 0; - } - } - if (accumCount > 0) // 1 or 2 digits remaining - appendBitsToBuffer(accumData, accumCount * 3 + 1, buf, &result.bitLength); - assert(result.bitLength == bitLen); - result.data = buf; - return result; -} - -// Public function - see documentation comment in header file. -struct qrcodegen_Segment -qrcodegen_makeAlphanumeric(const char *text, uint8_t buf[]) -{ - assert(text != NULL); - struct qrcodegen_Segment result; - size_t len = strlen(text); - result.mode = qrcodegen_Mode_ALPHANUMERIC; - int bitLen = calcSegmentBitLength(result.mode, len); - assert(bitLen != -1); - result.numChars = (int) len; - if (bitLen > 0) - memset(buf, 0, ((size_t) bitLen + 7) / 8 * sizeof(buf[0])); - result.bitLength = 0; - - unsigned int accumData = 0; - int accumCount = 0; - for (; *text != '\0'; text++) { - const char *temp = strchr(ALPHANUMERIC_CHARSET, *text); - assert(temp != NULL); - accumData = accumData * 45 + (unsigned int) (temp - ALPHANUMERIC_CHARSET); - accumCount++; - if (accumCount == 2) { - appendBitsToBuffer(accumData, 11, buf, &result.bitLength); - accumData = 0; - accumCount = 0; - } - } - if (accumCount > 0) // 1 character remaining - appendBitsToBuffer(accumData, 6, buf, &result.bitLength); - assert(result.bitLength == bitLen); - result.data = buf; - return result; -} - -// Public function - see documentation comment in header file. -struct qrcodegen_Segment -qrcodegen_makeEci(long assignVal, uint8_t buf[]) -{ - struct qrcodegen_Segment result; - result.mode = qrcodegen_Mode_ECI; - result.numChars = 0; - result.bitLength = 0; - if (assignVal < 0) - assert(false); - else if (assignVal < (1 << 7)) { - memset(buf, 0, 1 * sizeof(buf[0])); - appendBitsToBuffer(assignVal, 8, buf, &result.bitLength); - } else if (assignVal < (1 << 14)) { - memset(buf, 0, 2 * sizeof(buf[0])); - appendBitsToBuffer(2, 2, buf, &result.bitLength); - appendBitsToBuffer(assignVal, 14, buf, &result.bitLength); - } else if (assignVal < 1000000L) { - memset(buf, 0, 3 * sizeof(buf[0])); - appendBitsToBuffer(6, 3, buf, &result.bitLength); - appendBitsToBuffer(assignVal >> 10, 11, buf, &result.bitLength); - appendBitsToBuffer(assignVal & 0x3FF, 10, buf, &result.bitLength); - } else - assert(false); - result.data = buf; - return result; -} - -// 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 INT16_MAX. -testable int -getTotalBits(const struct qrcodegen_Segment segs[], size_t len, int version) -{ - assert(segs != NULL || len == 0); - long result = 0; - for (size_t i = 0; i < len; i++) { - int numChars = segs[i].numChars; - int bitLength = segs[i].bitLength; - assert(0 <= numChars && numChars <= INT16_MAX); - assert(0 <= bitLength && bitLength <= INT16_MAX); - int ccbits = numCharCountBits(segs[i].mode, version); - assert(0 <= ccbits && ccbits <= 16); - if (numChars >= (1L << ccbits)) - return -1; // The segment's length doesn't fit the field's bit width - result += 4L + ccbits + bitLength; - if (result > INT16_MAX) - return -1; // The sum might overflow an int type - } - assert(0 <= result && result <= INT16_MAX); - return (int) result; -} - -// Returns the bit width of the character count field for a segment in the given mode -// in a QR Code at the given version number. The result is in the range [0, 16]. -static int -numCharCountBits(enum qrcodegen_Mode mode, int version) -{ - assert(qrcodegen_VERSION_MIN <= version && version <= qrcodegen_VERSION_MAX); - int i = (version + 7) / 17; - switch (mode) { - case qrcodegen_Mode_NUMERIC: - { - static const int temp[] = {10, 12, 14}; - return temp[i]; - } - case qrcodegen_Mode_ALPHANUMERIC: - { - static const int temp[] = {9, 11, 13}; - return temp[i]; - } - case qrcodegen_Mode_BYTE: - { - static const int temp[] = {8, 16, 16}; - return temp[i]; - } - case qrcodegen_Mode_KANJI: - { - static const int temp[] = {8, 10, 12}; - return temp[i]; - } - case qrcodegen_Mode_ECI: - return 0; - default: - assert(false); - return -1; // Dummy value - } -} |