Added test cases for C function appendBitsToBuffer().

c/qrcodegen-test.c

@@ -44,6 +44,7 @@ static int numTestCases = 0;
 
 // Prototypes of private functions under test
 int getTextProperties(const char *text, bool *isNumeric, bool *isAlphanumeric, int *textBits);
+void appendBitsToBuffer(unsigned int val, int numBits, uint8_t buffer[], int *bitLen);
 int getNumDataCodewords(int version, enum qrcodegen_Ecc ecl);
 int getNumRawDataModules(int version);
 void calcReedSolomonGenerator(int degree, uint8_t result[]);
@@ -116,6 +117,47 @@ static void testGetTextProperties(void) {
 }
 
 
+static void testAppendBitsToBuffer(void) {
+	{
+		uint8_t buf[1] = {0};
+		int bitLen = 0;
+		appendBitsToBuffer(0, 0, buf, &bitLen);
+		assert(bitLen == 0);
+		assert(buf[0] == 0);
+		appendBitsToBuffer(1, 1, buf, &bitLen);
+		assert(bitLen == 1);
+		assert(buf[0] == 0x80);
+		appendBitsToBuffer(0, 1, buf, &bitLen);
+		assert(bitLen == 2);
+		assert(buf[0] == 0x80);
+		appendBitsToBuffer(5, 3, buf, &bitLen);
+		assert(bitLen == 5);
+		assert(buf[0] == 0xA8);
+		appendBitsToBuffer(6, 3, buf, &bitLen);
+		assert(bitLen == 8);
+		assert(buf[0] == 0xAE);
+		numTestCases++;
+	}
+	{
+		uint8_t buf[6] = {0};
+		int bitLen = 0;
+		appendBitsToBuffer(16942, 16, buf, &bitLen);
+		assert(bitLen == 16);
+		assert(buf[0] == 0x42 && buf[1] == 0x2E && buf[2] == 0x00 && buf[3] == 0x00 && buf[4] == 0x00 && buf[5] == 0x00);
+		appendBitsToBuffer(10, 7, buf, &bitLen);
+		assert(bitLen == 23);
+		assert(buf[0] == 0x42 && buf[1] == 0x2E && buf[2] == 0x14 && buf[3] == 0x00 && buf[4] == 0x00 && buf[5] == 0x00);
+		appendBitsToBuffer(15, 4, buf, &bitLen);
+		assert(bitLen == 27);
+		assert(buf[0] == 0x42 && buf[1] == 0x2E && buf[2] == 0x15 && buf[3] == 0xE0 && buf[4] == 0x00 && buf[5] == 0x00);
+		appendBitsToBuffer(26664, 15, buf, &bitLen);
+		assert(bitLen == 42);
+		assert(buf[0] == 0x42 && buf[1] == 0x2E && buf[2] == 0x15 && buf[3] == 0xFA && buf[4] == 0x0A && buf[5] == 0x00);
+		numTestCases++;
+	}
+}
+
+
 static void testGetNumDataCodewords(void) {
 	int cases[][3] = {
 		{ 3, 1,   44},
@@ -449,6 +491,7 @@ static void testGetSetModuleRandomly(void) {
 int main(void) {
 	srand(time(NULL));
 	testGetTextProperties();
+	testAppendBitsToBuffer();
 	testGetNumDataCodewords();
 	testGetNumRawDataModules();
 	testCalcReedSolomonGenerator();

c/qrcodegen.c

@@ -58,7 +58,7 @@ static int fitVersionToData(int minVersion, int maxVersion, enum qrcodegen_Ecc e
 	int dataLen, int dataBitLen, int ver1To9LenBits, int ver10To26LenBits, int ver27To40LenBits);
 static void encodeQrCodeTail(uint8_t dataAndQrcode[], int bitLen, uint8_t tempBuffer[],
 	int version, enum qrcodegen_Ecc ecl, enum qrcodegen_Mask mask, bool boostEcl);
-static void appendBitsToBuffer(unsigned int val, int numBits, uint8_t buffer[], int *bitLen);
+testable void appendBitsToBuffer(unsigned int val, int numBits, uint8_t buffer[], int *bitLen);
 
 static void appendErrorCorrection(uint8_t data[], int version, enum qrcodegen_Ecc ecl, uint8_t result[]);
 testable int getNumDataCodewords(int version, enum qrcodegen_Ecc ecl);
@@ -342,7 +342,7 @@ static void encodeQrCodeTail(uint8_t dataAndQrcode[], int bitLen, uint8_t tempBu
 
 
 // Appends the given sequence of bits to the given byte-based bit buffer, increasing the bit length.
-static void appendBitsToBuffer(unsigned int val, int numBits, uint8_t buffer[], int *bitLen) {
+testable void appendBitsToBuffer(unsigned int val, int numBits, uint8_t buffer[], int *bitLen) {
 	assert(0 <= numBits && numBits <= 16 && (long)val >> numBits == 0);
 	for (int i = numBits - 1; i >= 0; i--, (*bitLen)++)
 		buffer[*bitLen >> 3] |= ((val >> i) & 1) << (7 - (*bitLen & 7));