Update 'globalfunctions/DleEncoder.cpp'
Just a missing char
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281f13e27b
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@ -1,124 +1,124 @@
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#include "../globalfunctions/DleEncoder.h"
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DleEncoder::DleEncoder() {}
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DleEncoder::~DleEncoder() {}
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ReturnValue_t DleEncoder::encode(const uint8_t* sourceStream,
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size_t sourceLen, uint8_t* destStream, size_t maxDestLen,
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size_t* encodedLen, bool addStxEtx) {
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if (maxDestLen < 2) {
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return STREAM_TOO_SHORT;
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}
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size_t encodedIndex = 0, sourceIndex = 0;
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uint8_t nextByte;
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if (addStxEtx) {
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destStream[0] = STX_CHAR;
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++encodedIndex;
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}
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while (encodedIndex < maxDestLen and sourceIndex < sourceLen)
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{
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nextByte = sourceStream[sourceIndex];
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// STX, ETX and CR characters in the stream need to be escaped with DLE
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if (nextByte == STX_CHAR or nextByte == ETX_CHAR or nextByte == CARRIAGE_RETURN) {
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if (encodedIndex + 1 >= maxDestLen) {
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return STREAM_TOO_SHORT;
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}
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else {
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destStream[encodedIndex] = DLE_CHAR;
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++encodedIndex;
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/* Escaped byte will be actual byte + 0x40. This prevents
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* STX, ETX, and carriage return characters from appearing
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* in the encoded data stream at all, so when polling an
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* encoded stream, the transmission can be stopped at ETX.
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* 0x40 was chosen at random with special requirements:
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* - Prevent going from one control char to another
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* - Prevent overflow for common characters */
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destStream[encodedIndex] = nextByte + 0x40;
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}
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}
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// DLE characters are simply escaped with DLE.
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else if (nextByte == DLE_CHAR) {
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if (encodedIndex + 1 >= maxDestLen) {
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return STREAM_TOO_SHORT;
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}
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else {
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destStream[encodedIndex] = DLE_CHAR;
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++encodedIndex;
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destStream[encodedIndex] = DLE_CHAR;
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}
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}
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else {
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destStream[encodedIndex] = nextByte;
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}
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++encodedIndex;
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++sourceIndex;
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}
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if (sourceIndex == sourceLen and encodedIndex < maxDestLen) {
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if (addStxEtx) {
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destStream[encodedIndex] = ETX_CHAR;
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++encodedIndex;
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}
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*encodedLen = encodedIndex;
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return RETURN_OK;
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}
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else {
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return STREAM_TOO_SHORT;
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}
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}
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ReturnValue_t DleEncoder::decode(const uint8_t *sourceStream,
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size_t sourceStreamLen, size_t *readLen, uint8_t *destStream,
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size_t maxDestStreamlen, size_t *decodedLen) {
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size_t encodedIndex = 0, decodedIndex = 0;
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uint8_t nextByte;
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if (*sourceStream != STX_CHAR) {
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return DECODING_ERROR;
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}
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++encodedIndex;
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while ((encodedIndex < sourceStreamLen) && (decodedIndex < maxDestStreamlen)
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&& (sourceStream[encodedIndex] != ETX_CHAR)
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&& (sourceStream[encodedIndex] != STX_CHAR)) {
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if (sourceStream[encodedIndex] == DLE_CHAR) {
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nextByte = sourceStream[encodedIndex + 1];
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// The next byte is a DLE character that was escaped by another
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// DLE character, so we can write it to the destination stream.
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if (nextByte == DLE_CHAR) {
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destStream[decodedIndex] = nextByte;
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}
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else {
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/* The next byte is a STX, DTX or 0x0D character which
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* was escaped by a DLE character. The actual byte was
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* also encoded by adding + 0x40 to preven having control chars,
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* in the stream at all, so we convert it back. */
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if (nextByte == 0x42 or nextByte == 0x43 or nextByte == 0x4D) {
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destStream[decodedIndex] = nextByte - 0x40;
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}
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else {
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return DECODING_ERROR;
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}
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}
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++encodedIndex;
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}
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else {
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destStream[decodedIndex] = sourceStream[encodedIndex];
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}
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++encodedIndex;
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++decodedIndex;
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}
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if (sourceStream[encodedIndex] != ETX_CHAR) {
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*readLen = ++encodedIndex;
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return DECODING_ERROR;
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}
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else {
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*readLen = ++encodedIndex;
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*decodedLen = decodedIndex;
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return RETURN_OK;
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}
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}
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#include "../globalfunctions/DleEncoder.h"
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DleEncoder::DleEncoder() {}
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DleEncoder::~DleEncoder() {}
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ReturnValue_t DleEncoder::encode(const uint8_t* sourceStream,
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size_t sourceLen, uint8_t* destStream, size_t maxDestLen,
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size_t* encodedLen, bool addStxEtx) {
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if (maxDestLen < 2) {
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return STREAM_TOO_SHORT;
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}
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size_t encodedIndex = 0, sourceIndex = 0;
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uint8_t nextByte;
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if (addStxEtx) {
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destStream[0] = STX_CHAR;
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++encodedIndex;
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}
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while (encodedIndex < maxDestLen and sourceIndex < sourceLen)
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{
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nextByte = sourceStream[sourceIndex];
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// STX, ETX and CR characters in the stream need to be escaped with DLE
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if (nextByte == STX_CHAR or nextByte == ETX_CHAR or nextByte == CARRIAGE_RETURN) {
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if (encodedIndex + 1 >= maxDestLen) {
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return STREAM_TOO_SHORT;
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}
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else {
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destStream[encodedIndex] = DLE_CHAR;
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++encodedIndex;
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/* Escaped byte will be actual byte + 0x40. This prevents
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* STX, ETX, and carriage return characters from appearing
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* in the encoded data stream at all, so when polling an
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* encoded stream, the transmission can be stopped at ETX.
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* 0x40 was chosen at random with special requirements:
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* - Prevent going from one control char to another
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* - Prevent overflow for common characters */
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destStream[encodedIndex] = nextByte + 0x40;
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}
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}
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// DLE characters are simply escaped with DLE.
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else if (nextByte == DLE_CHAR) {
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if (encodedIndex + 1 >= maxDestLen) {
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return STREAM_TOO_SHORT;
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}
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else {
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destStream[encodedIndex] = DLE_CHAR;
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++encodedIndex;
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destStream[encodedIndex] = DLE_CHAR;
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}
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}
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else {
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destStream[encodedIndex] = nextByte;
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}
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++encodedIndex;
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++sourceIndex;
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}
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if (sourceIndex == sourceLen and encodedIndex < maxDestLen) {
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if (addStxEtx) {
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destStream[encodedIndex] = ETX_CHAR;
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++encodedIndex;
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}
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*encodedLen = encodedIndex;
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return RETURN_OK;
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}
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else {
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return STREAM_TOO_SHORT;
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}
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}
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ReturnValue_t DleEncoder::decode(const uint8_t *sourceStream,
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size_t sourceStreamLen, size_t *readLen, uint8_t *destStream,
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size_t maxDestStreamlen, size_t *decodedLen) {
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size_t encodedIndex = 0, decodedIndex = 0;
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uint8_t nextByte;
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if (*sourceStream != STX_CHAR) {
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return DECODING_ERROR;
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}
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++encodedIndex;
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while ((encodedIndex < sourceStreamLen) && (decodedIndex < maxDestStreamlen)
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&& (sourceStream[encodedIndex] != ETX_CHAR)
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&& (sourceStream[encodedIndex] != STX_CHAR)) {
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if (sourceStream[encodedIndex] == DLE_CHAR) {
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nextByte = sourceStream[encodedIndex + 1];
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// The next byte is a DLE character that was escaped by another
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// DLE character, so we can write it to the destination stream.
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if (nextByte == DLE_CHAR) {
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destStream[decodedIndex] = nextByte;
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}
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else {
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/* The next byte is a STX, DTX or 0x0D character which
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* was escaped by a DLE character. The actual byte was
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* also encoded by adding + 0x40 to prevent having control chars,
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* in the stream at all, so we convert it back. */
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if (nextByte == 0x42 or nextByte == 0x43 or nextByte == 0x4D) {
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destStream[decodedIndex] = nextByte - 0x40;
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}
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else {
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return DECODING_ERROR;
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}
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}
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++encodedIndex;
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}
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else {
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destStream[decodedIndex] = sourceStream[encodedIndex];
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}
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++encodedIndex;
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++decodedIndex;
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}
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if (sourceStream[encodedIndex] != ETX_CHAR) {
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*readLen = ++encodedIndex;
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return DECODING_ERROR;
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}
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else {
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*readLen = ++encodedIndex;
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*decodedLen = decodedIndex;
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return RETURN_OK;
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}
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}
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